@article {Bueler2021conservation, title = {Conservation laws for free-boundary fluid layers}, journal = {SIAM J. Appl. Math.}, volume = {81}, number = {5}, year = {2021}, pages = {2007{\textendash}2032}, doi = {10.1137/20M135217X}, author = {E. Bueler} } @book {Bueler2021, title = {{PETSc} for {P}artial {D}ifferential {E}quations: {N}umerical {S}olutions in {C} and {P}ython}, year = {2021}, publisher = {SIAM Press}, organization = {SIAM Press}, address = {Philadelphia}, url = {https://my.siam.org/Store/Product/viewproduct/?ProductId=32850137}, author = {E. Bueler} } @article {336, title = {Circumpolar Deep Water Impacts Glacial Meltwater Export and Coastal Biogeochemical Cycling Along the West Antarctic Peninsula}, journal = {Frontiers in Marine Science}, volume = {6}, year = {2019}, pages = {1{\textendash}23}, keywords = {Antarctic Peninsula, ice, meltwater, phytoplankton}, issn = {2296-7745}, doi = {10.3389/fmars.2019.00144}, url = {https://www.frontiersin.org/article/10.3389/fmars.2019.00144/full}, author = {Cape, Mattias R. and Vernet, Maria and Pettit, Erin C. and Wellner, Julia and Truffer, Martin and Akie, Garrett and Domack, Eugene and Leventer, Amy and Smith, Craig R. and Huber, Bruce A.} } @article {Aschwanden2019, title = {{Contribution of the Greenland Ice Sheet to sea level over the next millennium}}, journal = {Science Advances}, volume = {5}, number = {6}, year = {2019}, month = {jun}, pages = {eaav9396}, abstract = {The Greenland Ice Sheet holds 7.2 m of sea level equivalent and in recent decades, rising temperatures have led to accelerated mass loss. Current ice margin recession is led by the retreat of outlet glaciers, large rivers of ice ending in narrow fjords that drain the interior. We pair an outlet glacier{\textendash}resolving ice sheet model with a comprehensive uncertainty quantification to estimate Greenland{\textquoteright}s contribution to sea level over the next millennium. We find that Greenland could contribute 5 to 33 cm to sea level by 2100, with discharge from outlet glaciers contributing 8 to 45\% of total mass loss. Our analysis shows that uncertainties in projecting mass loss are dominated by uncertainties in climate scenarios and surface processes, whereas uncertainties in calving and frontal melt play a minor role. We project that Greenland will very likely become ice free within a millennium without substantial reductions in greenhouse gas emissions.}, issn = {2375-2548}, doi = {10.1126/sciadv.aav9396}, url = {http://advances.sciencemag.org/lookup/doi/10.1126/sciadv.aav9396}, author = {Aschwanden, Andy and Fahnestock, Mark A. and Truffer, Martin and Brinkerhoff, Douglas J. and Hock, Regine and Khroulev, Constantine and Mottram, Ruth and Khan, S. Abbas} } @article {333, title = {The Larsen Ice Shelf System, Antarctica (LARISSA): Polar Systems Bound Together, Changing Fast}, journal = {GSA Today}, volume = {29}, year = {2019}, pages = {4{\textendash}10}, abstract = {Climatic, cryospheric, and biologic changes taking place in the northern Antarctic Peninsula provide examples for how ongoing systemic change may pro- gress through the entire Antarctic system. A large, interdisciplinary research project focused on the Larsen Ice Shelf system, synthesized here, has documented dramatic ice cover, oceanographic, and ecosystem changes in the Antarctic Peninsula during the Holocene and the present period of rapid regional warming. The responsive- ness of the region results from its position in the climate and ocean system, in which a narrow continental block extends across zonal atmospheric and ocean flow, creating high snow accumulation, strong gradients and gyres, dynamic oceanography, outlet glaciers feeding into many fjords and bays having steep topography, and a continental shelf that contains many glacially carved troughs separated by areas of glacial sedi- ment accumulation. The microcosm of the northern Antarctic Peninsula has a ten- dency to change rapidly{\textemdash}rapid relative not just to Antarctica{\textquoteright}s mainland but compared to the rest of the planet as well{\textemdash}and it is generally warmer than the rest of Antarctica. Both its Holocene and modern glaciological retreats offer a picture of how larger areas of Antarctica farther south might change under future warming.}, issn = {10525173}, doi = {10.1130/gsatg382a.1}, author = {Wellner, Julia and Scambos, Ted and Domack, Eugene and Vernet, Maria and Leventer, Amy and Balco, Greg and Brachfeld, Stefanie and Cape, Mattias and Huber, Bruce and Ishman, Scott and McCormick, Michael and Mosley-Thompson, Ellen and Pettit, Erin and Smith, Craig and Truffer, Martin and Van Dover, Cindy and Yoo, Kyu-Cheul} } @article {337, title = {Non-linear glacier response to calving events, Jakobshavn Isbr{\ae}, Greenland}, journal = {Journal of Glaciology}, volume = {65}, year = {2019}, pages = {39{\textendash}54}, abstract = {Jakobshavn Isbr{\ae}, a tidewater glacier that produces some of Greenland{\textquoteright}s largest icebergs and highest speeds, reached record-high flow rates in 2012 (Joughin and others, 2014). We use terrestrial radar interferometric observations from August 2012 to characterize the events that led to record-high flow. We find that the highest speeds occurred in response to a small calving retreat, while several larger calving events produced negligible changes in glacier speed. This non-linear response to calving events suggests the terminus was close to flotation and therefore highly sensitive to terminus position. Our observations indicate that a glacier{\textquoteright}s response to calving is a consequence of two competing feedbacks: (1) an increase in strain rates that leads to dynamic thinning and faster flow, thereby promoting destabilization, and (2) an increase in flow rates that advects thick ice toward the terminus and promotes restabilization. The competition between these feedbacks depends on temporal and spatial variations in the glacier{\textquoteright}s proximity to flotation. This study highlights the importance of dynamic thinning and advective processes on tidewater glacier stability, and further suggests the latter may be limiting the current retreat due to the thick ice that occupies Jakobshavn Isbr{\ae}{\textquoteright}s retrograde bed.}, keywords = {calving, dynamic thinning, Jakobshavn Isbr{\ae}, terrestrial radar interferometry, tidewater glaciers}, issn = {00221430}, doi = {10.1017/jog.2018.90}, author = {Cassotto, Ryan and Fahnestock, Mark and Amundson, Jason M. and Truffer, Martin and Boettcher, Margaret S. and De La Pe{\~n}a, Santiago and Howat, Ian} } @article {alexander_simulated_2019, title = {Simulated {Greenland} {Surface} {Mass} {Balance} in the {GISS} {ModelE2} {GCM}: {Role} of the {Ice} {Sheet} {Surface}}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {124}, number = {3}, year = {2019}, pages = {750{\textendash}765}, abstract = {The rate of growth or retreat of the Greenland and Antarctic ice sheets remains a highly uncertain component of future sea level change. Here we examine the simulation of Greenland ice sheet surface mass balance (GrIS SMB) in a development branch of the ModelE2 version of the NASA Goddard Institute for Space Studies (GISS) general circulation model (GCM). GCMs are often limited in their ability to represent SMB compared with polar region regional climate models. We compare ModelE2-simulated GrIS SMB for present-day (1996{\textendash}2005) simulations with fixed ocean conditions, at a spatial resolution of 2{\textdegree} latitude by 2.5{\textdegree} longitude ({\textasciitilde}200 km), with SMB simulated by the Mod{\`e}le Atmosph{\'e}rique R{\'e}gionale (MAR) regional climate model (1996{\textendash}2005 at a 25-km resolution). ModelE2 SMB agrees well with MAR SMB on the whole, but there are distinct spatial patterns of differences and large differences in some SMB components. The impacts of changes to the ModelE2 surface are tested, including a subgrid-scale representation of SMB with surface elevation classes. This has a minimal effect on ice sheet-wide SMB but corrects local biases. Replacing fixed surface albedo with satellite-derived values and an age-dependent scheme has a larger impact, increasing simulated melt by 60\%{\textendash}100\%. We also find that lower surface albedo can enhance the effects of elevation classes. Reducing ModelE2 surface roughness length to values closer to MAR reduces sublimation by {\textasciitilde}50\%. Further work is required to account for meltwater refreezing in ModelE2 and to understand how differences in atmospheric processes and model resolution influence simulated SMB. Plain Language Summary Melting of the Earth{\textquoteright}s ice sheets represents a substantial contribution to global sea level rise. Global climate model simulations of Earth{\textquoteright}s climate often model the surface of ice sheets in a fairly simple way because of computational limitations. This study evaluates the representation of the Greenland ice sheet in one such global model simulation (from the NASA Goddard Institute for Space Studies general circulation model) against a regional model that simulates only the local Greenland area in a higher degree of detail. The study finds that the global model simulation of the Greenland ice sheet is sensitive to how the model represents the ice sheet surface, in particular, how it reflects incoming sunlight, stores and freezes liquid water, and simulates surface evaporation. Attempting to improve the simulation by dividing the ice sheet surface into additional grid cells according to surface elevation has a minor impact on the simulation. The study reveals how the representation of the Greenland ice sheet in ModelE2 might be improved to better estimate ice sheet change and the sea level response to global climate changes.}, keywords = {1911-UW}, issn = {2169-9003, 2169-9011}, doi = {10.1029/2018JF004772}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2018JF004772}, author = {Alexander, P. M. and LeGrande, A. N. and Fischer, E. and Tedesco, M. and Fettweis, X. and Kelley, M. and Nowicki, S. M. J. and Schmidt, G. A.} } @article {334, title = {Spatio-temporal variations in seasonal ice tongue submarine melt rate at a tidewater glacier in southwest Greenland}, journal = {J. Glaciol.}, year = {2019}, pages = {1{\textendash}8}, keywords = {glacier calving, ice, ocean interactions, Remote sensing, subglacial processes}, doi = {10.1017/jog.2019.27}, author = {Moyer, A N and Nienow, P W and Gourmelen, N and Sole, A J and Truffer, M and Fahnestock, M and Slater, D A} } @article {335, title = {Tracking icebergs with time-lapse photography and sparse optical flow , LeConte Bay , Alaska , 2016 {\textendash} 2017}, journal = {J. Glaciol.}, volume = {65}, year = {2019}, pages = {195{\textendash}211}, keywords = {glaciological instruments and methods, ice, icebergs, ocean interactions, Remote sensing}, doi = {10.1017/jog.2018.105}, author = {Kienholz, Christian and Amundson, Jason M and Motyka, Roman J and Jackson, Rebecca H and Mickett, John B and Sutherland, David A and Nash, Jonathan D and Winters, Dylan S and Dryer, William P and Truffer, Martin} } @article {oct, title = {Active seismic studies in valley glacier settings: strategies and limitations}, journal = {Journal of Glaciology}, volume = {64}, year = {2018}, month = {oct}, pages = {796{\textendash}810}, abstract = {Subglacial tills play an important role in glacier dynamics but are difficult to characterize in situ. Amplitude Variation with Angle (AVA) analysis of seismic reflection data can distinguish between stiff tills and deformable tills. However, AVA analysis in mountain glacier environments can be problematic: reflections can be obscured by Rayleigh wave energy scattered from crevasses, and complex basal topography can impede the location of reflection points in 2-D acquisitions. We use a forward model to produce challenging synthetic seismic records in order to test the efficacy of AVA in crevassed and geometrically complex environments. We find that we can distinguish subglacial till types in moderately crevassed environments, where {\textquoteleft}moderate{\textquoteright} depends on crevasse spacing and orientation. The forward model serves as a planning tool, as it can predict AVA success or failure based on characteristics of the study glacier. Applying lessons from the forward model, we perform AVA on a seismic dataset collected from Taku Glacier in Southeast Alaska in March 2016. Taku Glacier is a valley glacier thought to overlay thick sediment deposits. A near-offset polarity reversal confirms that the tills are deformable.}, keywords = {glacial tills, glacier geophysics, glaciological instruments and methods, seismics, subglacial}, issn = {0022-1430}, doi = {10.1017/jog.2018.69}, url = {https://www.cambridge.org/core/product/identifier/S0022143018000692/type/journal{\_}article}, author = {ZECHMANN, JENNA M. and BOOTH, ADAM D. and Truffer, Martin and Gusmeroli, Alessio and Amundson, Jason M. and Larsen, Christopher F.} } @article {Goelzer2018, title = {{Design and results of the ice sheet model initialisation experiments initMIP-Greenland: an ISMIP6 intercomparison}}, journal = {The Cryosphere}, volume = {12}, number = {4}, year = {2018}, month = {apr}, pages = {1433{\textendash}1460}, abstract = {Abstract. Earlier large-scale Greenland ice sheet sea-level projections (e.g. those run during the ice2sea and SeaRISE initiatives) have shown that ice sheet initial conditions have a large effect on the projections and give rise to important uncertainties. The goal of this initMIP-Greenland intercomparison exercise is to compare, evaluate, and improve the initialisation techniques used in the ice sheet modelling community and to estimate the associated uncertainties in modelled mass changes. initMIP-Greenland is the first in a series of ice sheet model intercomparison activities within ISMIP6 (the Ice Sheet Model Intercomparison Project for CMIP6), which is the primary activity within the Coupled Model Intercomparison Project Phase 6 (CMIP6) focusing on the ice sheets. Two experiments for the large-scale Greenland ice sheet have been designed to allow intercomparison between participating models of (1) the initial present-day state of the ice sheet and (2) the response in two idealised forward experiments. The forward experiments serve to evaluate the initialisation in terms of model drift (forward run without additional forcing) and in response to a large perturbation (prescribed surface mass balance anomaly); they should not be interpreted as sea-level projections. We present and discuss results that highlight the diversity of data sets, boundary conditions, and initialisation techniques used in the community to generate initial states of the Greenland ice sheet. We find good agreement across the ensemble for the dynamic response to surface mass balance changes in areas where the simulated ice sheets overlap but differences arising from the initial size of the ice sheet. The model drift in the control experiment is reduced for models that participated in earlier intercomparison exercises.}, issn = {1994-0424}, doi = {10.5194/tc-12-1433-2018}, url = {https://www.the-cryosphere.net/12/1433/2018/}, author = {Goelzer, Heiko and Nowicki, Sophie and Edwards, Tamsin and Beckley, Matthew and Abe-Ouchi, Ayako and Aschwanden, Andy and Calov, Reinhard and Gagliardini, Olivier and Gillet-Chaulet, Fabien and Golledge, Nicholas R. and Gregory, Jonathan and Greve, Ralf and Humbert, Angelika and Huybrechts, Philippe and Kennedy, Joseph H. and Larour, Eric and Lipscomb, William H. and Le clec\'h, S{\'e}bastien and Lee, Victoria and Morlighem, Mathieu and Pattyn, Frank and Payne, Antony J. and Rodehacke, Christian and R{\"u}ckamp, Martin and Saito, Fuyuki and Schlegel, Nicole and Seroussi, Helene and Shepherd, Andrew and Sun, Sainan and van de Wal, Roderik and Ziemen, Florian A.} } @article {Kiaer2018, title = {{A large impact crater beneath Hiawatha Glacier in northwest Greenland}}, journal = {Science Advances}, volume = {4}, number = {11}, year = {2018}, month = {nov}, pages = {eaar8173}, abstract = {We report the discovery of a large impact crater beneath Hiawatha Glacier in northwest Greenland. From airborne radar surveys, we identify a 31-kilometer-wide, circular bedrock depression beneath up to a kilometer of ice. This depression has an elevated rim that cross-cuts tributary subglacial channels and a subdued central uplift that appears to be actively eroding. From ground investigations of the deglaciated foreland, we identify overprinted structures within Precambrian bedrock along the ice margin that strike tangent to the subglacial rim. Glaciofluvial sediment from the largest river draining the crater contains shocked quartz and other impact-related grains. Geochemical analysis of this sediment indicates that the impactor was a fractionated iron asteroid, which must have been more than a kilometer wide to produce the identified crater. Radiostratigraphy of the ice in the crater shows that the Holocene ice is continuous and conformable, but all deeper and older ice appears to be debris rich or heavily disturbed. The age of this impact crater is presently unknown, but from our geological and geophysical evidence, we conclude that it is unlikely to predate the Pleistocene inception of the Greenland Ice Sheet.}, issn = {23752548}, doi = {10.1126/sciadv.aar8173}, url = {http://advances.sciencemag.org/ http://advances.sciencemag.org/lookup/doi/10.1126/sciadv.aar8173}, author = {Kj{\ae}r, Kurt H. and Larsen, Nicolaj K and Binder, Tobias and Bj{\o}rk, Anders A and Eisen, Olaf and Fahnestock, Mark A and Funder, Svend and Garde, Adam A and Haack, Henning and Helm, Veit and Houmark-Nielsen, Michael and Kjeldsen, Kristian K and Khan, Shfaqat A and Machguth, Horst and McDonald, Iain and Morlighem, Mathieu and Mouginot, J{\'e}r{\'e}mie and Paden, John D and Waight, Tod E and Weikusat, Christian and Willerslev, Eske and MacGregor, Joseph A.} } @article {Roth2018, title = {{Modeling Winter Precipitation Over the Juneau Icefield, Alaska, Using a Linear Model of Orographic Precipitation}}, journal = {Frontiers in Earth Science}, volume = {6}, number = {March}, year = {2018}, month = {mar}, pages = {1{\textendash}19}, keywords = {Alaska, downscaling, glacier mass balance, Juneau Icefield, Modeling, orographic precipitation, snow accumulation}, issn = {2296-6463}, doi = {10.3389/feart.2018.00020}, url = {http://journal.frontiersin.org/article/10.3389/feart.2018.00020/full}, author = {Roth, Aurora and Hock, Regine and Schuler, Thomas V. and Bieniek, Peter A. and Pelto, Mauri and Aschwanden, Andy} } @article {344, title = {Acquisition of a 3 min, two-dimensional glacier velocity field with terrestrial radar interferometry}, journal = {Journal of Glaciology}, year = {2017}, pages = {1{\textendash}8}, abstract = {{\textless}p{\textgreater}Outlet glaciers undergo rapid spatial and temporal changes in flow velocity during calving events. Observing such changes requires both high temporal and high spatial resolution methods, something now possible with terrestrial radar interferometry. While a single such radar provides line-of-sight velocity, two radars define both components of the horizontal flow field. To assess the feasibility of obtaining the two-dimensional (2-D) flow field, we deployed two terrestrial radar interferometers at Jakobshavn Isbrae, a major outlet glacier on Greenland{\textquoteright}s west coast, in the summer of 2012. Here, we develop and demonstrate a method to combine the line-of-sight velocity data from two synchronized radars to produce a 2-D velocity field from a single (3 min) interferogram. Results are compared with the more traditional feature-tracking data obtained from the same radar, averaged over a longer period. We demonstrate the potential and limitations of this new dual-radar approach for obtaining high spatial and temporal resolution 2-D velocity fields at outlet glaciers.{\textless}/p{\textgreater}}, keywords = {glacier flow, glacier geophysics, glaciological instruments and methods}, issn = {0022-1430}, doi = {10.1017/jog.2017.28}, url = {https://www.cambridge.org/core/product/identifier/S0022143017000284/type/journal{\_}article}, author = {Voytenko, Denis and Dixon, Timothy H. and Holland, David M. and Cassotto, Ryan and Howat, Ian M. and Fahnestock, Mark A. and Truffer, Martin and De La Pe{\~n}a, Santiago} } @article {apr, title = {Asynchronous behavior of outlet glaciers feeding Godth{\aa}bsfjord (Nuup Kangerlua) and the triggering of Narsap Sermia{\textquoteright}s retreat in SW Greenland}, journal = {J. Glaciol.}, volume = {63}, year = {2017}, month = {apr}, pages = {288{\textendash}308}, abstract = {We assess ice loss and velocity changes between 1985 and 2014 of three tidewater and five-land terminating glaciers in Godth{\aa}bsfjord (Nuup Kangerlua), Greenland. Glacier thinning accounted for 43.8 {\textpm} 0.2 km 3 of ice loss, equivalent to 0.10 mm eustatic sea-level rise. An additional 3.5 {\textpm} 0.3 km 3 was lost to the calving retreats of Kangiata Nunaata Sermia (KNS) and Narsap Sermia (NS), two tidewater glaciers that exhibited asynchronous behavior over the study period. KNS has retreated 22 km from its Little Ice Age (LIA) maximum (1761 AD), of which 0.8 km since 1985. KNS has stabilized in shallow water, but seasonally advects a 2 km long floating tongue. In contrast, NS began retreating from its LIA moraine in 2004{\textendash}06 (0.6 km), re-stabilized, then retreated 3.3 km during 2010{\textendash}14 into an over-deepened basin. Velocities at KNS ranged 5{\textendash}6 km a -1 , while at NS they increased from 1.5 to 5.5 km a -1 between 2004 and 2014. We present comprehensive analyses of glacier thinning, runoff, surface mass balance, ocean conditions, submarine melting, bed topography, ice m{\'e}lange and conclude that the 2010{\textendash}14 NS retreat was triggered by a combination of factors but primarily by an increase in submarine melting.}, keywords = {glacier calving, glacier discharge, glacier mass balance, ice/atmosphere interactions, ice/ocean interactions, tidewater glaciers}, issn = {0022-1430}, doi = {10.1017/jog.2016.138}, author = {Motyka, Roman J. and Cassotto, Ryan and Truffer, Martin and Kjeldsen, Kristian K. and Van As, Dirk and Korsgaard, Niels J. and Fahnestock, Mark and Howat, Ian and Langen, Peter L. and Mortensen, John and Lennert, Kunuk and Rysgaard, S{\o}ren} } @article {313, title = {Diagnosing the decline in climatic mass balance of glaciers in Svalbard over 1957{\textendash}2014}, journal = {The Cryosphere}, volume = {11}, year = {2017}, pages = {191{\textendash}215}, doi = {10.5194/tc-11-191-2017}, url = {https://www.the-cryosphere.net/11/191/2017/}, author = {{\O}stby, T. I. and Schuler, T. V. and Hagen, J. O. and Hock, R. and Kohler, J. and Reijmer, C. H.} } @article {dec, title = {Error sources in basal yield stress inversions for Jakobshavn Isbr{\ae}, Greenland, derived from residual patterns of misfit to observations}, journal = {Journal of Glaciology}, volume = {63}, year = {2017}, month = {dec}, pages = {999{\textendash}1011}, abstract = {The basal interface of glaciers is generally not directly observable. Geophysical inverse methods are therefore used to infer basal parameters from surface observations. Such methods can also provide information about potential inadequacies of the forward model. Ideally an inverse problem can be regularized so that the differences between modeled and observed surface velocities reflect observational errors. However, deficiencies in the forward model usually result in additional errors. Here we use the spatial pattern of velocity residuals to discuss the main error sources for basal stress inversions for Jakobshavn Isbr{\ae}, Greenland. Synthetic tests with prescribed patterns of basal yield stress with varying length scales are then used to investigate different weighting functions for the data-model misfit and for the ability of the inversion to resolve details in basal yield stress. We also test real-data inversions for their sensitivities to prior estimate, forward model parameters, data gaps, and temperature fields. We find that velocity errors are not sufficient to explain the residual patterns of real-data inversions. Conversely, ice-geometry errors and especially simulated errors in model simplifications are capable of reproducing similar error patterns and magnitudes. We suggest that residual patterns can provide useful guidance for forward model improvements.}, keywords = {glacier modeling, ice-sheet modeling, subglacial processes}, issn = {0022-1430}, doi = {10.1017/jog.2017.61}, url = {https://www.cambridge.org/core/product/identifier/S0022143017000612/type/journal{\_}article}, author = {Habermann, Marijke and Truffer, Martin and Maxwell, David} } @article {312, title = {Glacier Changes in the Susitna Basin, Alaska, USA,(1951{\textendash}2015) using GIS and Remote Sensing Methods}, journal = {Remote Sensing}, volume = {9}, year = {2017}, pages = {478}, author = {Wastlhuber, Roland and Hock, Regine and Kienholz, Christian and Braun, Matthias} } @article {310, title = {Grand Challenges in Cryospheric Sciences: Toward Better Predictability of Glaciers, Snow and Sea Ice}, journal = {Frontiers in Earth Science}, volume = {5}, year = {2017}, pages = {64}, issn = {2296-6463}, doi = {10.3389/feart.2017.00064}, url = {http://journal.frontiersin.org/article/10.3389/feart.2017.00064}, author = {Hock, Regine and Hutchings, Jennifer K. and Lehning, Michael} } @article {308, title = {Hypsometric control on glacier mass balance sensitivity in Alaska and northwest Canada}, journal = {Earth{\textquoteright}s Future}, year = {2017}, keywords = {Distribution, glaciers, hypsometry, mass balance, Modeling, modelling}, issn = {2328-4277}, doi = {10.1002/2016EF000479}, url = {http://dx.doi.org/10.1002/2016EF000479}, author = {McGrath, D. and Sass, L. and O{\textquoteright}Neel, S. and Arendt, A. and Kienholz, C.} } @article {311, title = {Mass Balance Evolution of Black Rapids Glacier, Alaska, 1980{\textendash}2100, and Its Implications for Surge Recurrence}, journal = {Frontiers in Earth Science}, volume = {5}, year = {2017}, pages = {56}, abstract = {Surge-type Black Rapids Glacier, Alaska, has undergone strong retreat since it last surged in 1936-37. To assess its evolution during the late 20th and 21st centuries and determine potential implications for surge likelihood, we run a simplified glacier model over the periods 1980-2015 (hindcasting) and 2015-2100 (forecasting). The model is forced by daily temperature and precipitation fields, with downscaled reanalysis data used for the hindcasting. A constant climate scenario and an RCP 8.5 scenario based on the GFDL-CM3 climate model are employed for the forecasting. Debris evolution is accounted for by a debris layer time series derived from satellite imagery (hindcasting) and a parametrized debris evolution model (forecasting). A retreat model accounts for the evolution of the glacier geometry. Model calibration, validation and parametrization rely on an extensive set of in situ and remotely sensed observations. To explore uncertainties in our projections, we run the glacier model in a Monte Carlo fashion, varying key model parameters and input data within plausible ranges. Our results for the hindcasting period indicate a negative mass balance trend, caused by atmospheric warming in the summer, precipitation decrease in the winter and surface elevation lowering (climate-elevation feedback), which exceed the moderating effects from increasing debris cover and glacier retreat. Without the 2002 rockslide deposits on Black Rapids{\textquoteright} lower reaches, the mass balances would be more negative, by ~20\% between the 2003 and 2015 mass-balance years. Despite its retreat, Black Rapids Glacier is substantially out of balance with the current climate. By 2100, ~8\% of Black Rapids{\textquoteright} 1980 area are projected to vanish under the constant climate scenario and ~73\% under the RCP 8.5 scenario. For both scenarios, the remaining glacier portions are out of balance, suggesting continued retreat after 2100. Due to mass starvation, a surge in the 21st century is unlikely. The projected retreat will affect the glacier{\textquoteright}s runoff and change the landscape in the Black Rapids area markedly.}, issn = {2296-6463}, doi = {10.3389/feart.2017.00056}, url = {http://journal.frontiersin.org/article/10.3389/feart.2017.00056}, author = {Kienholz, Christian and Hock, Regine and Truffer, Martin and Bieniek, Peter and Lader, Richard} } @article {2017/07/21, title = {Sediment transport drives tidewater glacier periodicity}, volume = {8}, year = {2017}, month = {2017/07/21}, pages = {90}, abstract = {Most of Earth{\textquoteright}s glaciers are retreating, but some tidewater glaciers are advancing despite increasing temperatures and contrary to their neighbors. This can be explained by the coupling of ice and sediment dynamics: a shoal forms at the glacier terminus, reducing ice discharge and causing advance towards an unstable configuration followed by abrupt retreat, in a process known as the tidewater glacier cycle. Here we use a numerical model calibrated with observations to show that interactions between ice flow, glacial erosion, and sediment transport drive these cycles, which occur independent of climate variations. Water availability controls cycle period and amplitude, and enhanced melt from future warming could trigger advance even in glaciers that are steady or retreating, complicating interpretations of glacier response to climate change. The resulting shifts in sediment and meltwater delivery from changes in glacier configuration may impact interpretations of marine sediments, fjord geochemistry, and marine ecosystems.}, isbn = {2041-1723}, url = {https://doi.org/10.1038/s41467-017-00095-5}, author = {Brinkerhoff, Douglas and Truffer, Martin and Aschwanden, Andy} } @article {jan, title = {Sub-ice-shelf sediments record history of twentieth-century retreat of Pine Island Glacier}, journal = {Nature}, volume = {541}, year = {2017}, month = {jan}, pages = {77{\textendash}80}, abstract = {The West Antarctic Ice Sheet is one of the largest potential sources of rising sea levels. Over the past 40 years, glaciers flowing into the Amundsen Sea sector of the ice sheet have thinned at an accelerating rate, and several numerical models suggest that unstable and irreversible retreat of the grounding line{\textemdash}which marks the boundary between grounded ice and floating ice shelf{\textemdash}is underway. Understanding this recent retreat requires a detailed knowledge of grounding-line history, but the locations of the grounding line before the advent of satellite monitoring in the 1990s are poorly dated. In particular, a history of grounding-line retreat is required to understand the relative roles of contemporaneous ocean-forced change and of ongoing glacier response to an earlier perturbation in driving ice-sheet loss. Here we show that the present thinning and retreat of Pine Island Glacier in West Antarctica is part of a climatically forced trend that was triggered in the 1940s. Our conclusions arise from analysis of sediment cores recovered beneath the floating Pine Island Glacier ice shelf, and constrain the date at which the grounding line retreated from a prominent seafloor ridge. We find that incursion of marine water beyond the crest of this ridge, forming an ocean cavity beneath the ice shelf, occurred in 1945 ({\textpm}12 years); final ungrounding of the ice shelf from the ridge occurred in 1970 ({\textpm}4 years). The initial opening of this ocean cavity followed a period of strong warming of West Antarctica, associated with El Ni{\~n}o activity. Thus our results suggest that, even when climate forcing weakened, ice-sheet retreat continued.}, keywords = {Antarctica, Pine Island glacier}, issn = {0028-0836}, doi = {10.1038/nature20136}, url = {http://dx.doi.org/10.1038/nature20136{\%}5Cnhttp://www.nature.com/doifinder/10.1038/nature20136 http://www.nature.com/articles/nature20136}, author = {Smith, J. A. and Andersen, T. J. and Shortt, M. and Gaffney, A. M. and Truffer, Martin and Stanton, T P and Bindschadler, Robert and Dutrieux, Pierre and Jenkins, Adrian and Hillenbrand, C.-D. and Ehrmann, Werner and Corr, H. F. J. and Farley, N. and Crowhurst, S. and Vaughan, David G.} } @article {349, title = {Automated detection of unstable glacier flow and a spectrum of speedup behavior in the Alaska Range}, journal = {Journal of Geophysical Research F: Earth Surface}, volume = {121}, year = {2016}, pages = {64{\textendash}81}, keywords = {automated detection, debris cover, pulse-type glaciers, spectrum of glacier flow instabilities, surge-type glaciers}, issn = {21699011}, doi = {10.1002/2015JF003502}, author = {Herreid, Sam and Truffer, Martin} } @article {Brinkerhoff2016, title = {{Bayesian Inference of Subglacial Topography Using Mass Conservation}}, journal = {Frontiers in Earth Science}, volume = {4}, year = {2016}, month = {feb}, pages = {1{\textendash}27}, abstract = {We develop a Bayesian model for estimating ice thickness given sparse observations coupled with estimates of surface mass balance, surface elevation change, and surface velocity. These fields are related through mass conservation. We use the Metropolis-Hastings algorithm to sample from the posterior probability distribution of ice thickness for three cases: a synthetic mountain glacier, ̈ Storglaci aren, and Jakobshavn Isbr{\ae}. Use of continuity in interpolation improves thickness estimates where relative velocity and surface mass balance errors are small, a condition difficult to maintain in regions of slow flow and surface mass balance near zero. Estimates of thickness uncertainty depend sensitively on spatial correlation. When this structure is known, we suggest a thickness measurement spacing of one to two times the correlation length to take best advantage of continuity based interpolation techniques. To determine ideal measurement spacing, the structure of spatial correlation must be better quantified.}, issn = {2296-6463}, doi = {10.3389/feart.2016.00008}, url = {http://journal.frontiersin.org/article/10.3389/feart.2016.00008}, author = {Brinkerhoff, Douglas J and Aschwanden, Andy and Truffer, Martin} } @article {Aschwanden2016, title = {{Complex Greenland outlet glacier flow captured}}, journal = {Nature Communications}, volume = {7}, year = {2016}, month = {feb}, pages = {10524}, issn = {2041-1723}, doi = {10.1038/ncomms10524}, url = {http://www.nature.com/doifinder/10.1038/ncomms10524}, author = {Aschwanden, Andy and Fahnestock, Mark A and Truffer, Martin} } @article {306, title = {Geodetic mass balance of surge-type Black Rapids Glacier, Alaska, 1980{\textendash}2001{\textendash}2010, including role of rockslide deposition and earthquake displacement}, journal = {Journal of Geophysical Research: Earth Surface}, year = {2016}, author = {Kienholz, C and Hock, R and Truffer, M and Arendt, A and Arko, S} } @article {Khan2016, title = {{Geodetic measurements reveal similarities between post-Last Glacial Maximum and present-day mass loss from the Greenland ice sheet}}, journal = {Science Advances}, volume = {2}, number = {9}, year = {2016}, month = {sep}, pages = {e1600931{\textendash}e1600931}, issn = {2375-2548}, doi = {10.1126/sciadv.1600931}, url = {http://advances.sciencemag.org/cgi/doi/10.1126/sciadv.1600931}, author = {Khan, Shfaqat A and Sasgen, Ingo and Bevis, Michael and van Dam, T. and Bamber, Jonathan L and Wahr, John and Willis, Michael and Kjaer, K. H. and Wouters, Bert and Helm, Veit and Csatho, Beata and Fleming, Kevin and Bjork, A. A. and Aschwanden, Andy and Knudsen, Per and Munneke, Peter Kuipers} } @article {MacGregor2016, title = {{Holocene deceleration of the Greenland Ice Sheet}}, journal = {Science}, volume = {351}, number = {6273}, year = {2016}, month = {feb}, pages = {590{\textendash}593}, issn = {0036-8075}, doi = {10.1126/science.aab1702}, url = {http://www.sciencemag.org/cgi/doi/10.1126/science.aab1702}, author = {MacGregor, J. A. and Colgan, W. T. and Fahnestock, M. A. and Morlighem, M. and Catania, G. A. and Paden, J. D. and Gogineni, S. P.} } @article {Brinkerhoffetal2016, title = {Inversion of a glacier hydrology model}, journal = {Ann. Glaciol.}, volume = {57}, number = {72}, year = {2016}, pages = {84{\textendash}95}, doi = {10.1017/aog.2016.3}, author = {D. J. Brinkerhoff and C. R. Meyer and E. Bueler and M. Truffer} } @article {309, title = {Modeling the evolution of the Juneau Icefield between 1971 and 2100 using the Parallel Ice Sheet Model (PISM)}, journal = {Journal of Glaciology}, volume = {62}, year = {2016}, pages = {199{\textendash}214}, author = {Ziemen, Florian A and Hock, Regine and Aschwanden, Andy and Khroulev, Constantine and Kienholz, Christian and MELKONIAN, ANDREW and ZHANG, JING} } @article {Muresan2016, title = {{Modelled glacier dynamics over the last quarter of a century at Jakobshavn Isbr{\ae}}}, journal = {The Cryosphere}, volume = {10}, number = {2}, year = {2016}, month = {mar}, pages = {597{\textendash}611}, issn = {1994-0424}, doi = {10.5194/tc-10-597-2016}, url = {http://www.the-cryosphere.net/10/597/2016/}, author = {Muresan, Ioana S. and Khan, Shfaqat A. and Aschwanden, Andy and Khroulev, Constantine and Van Dam, Tonie and Bamber, Jonathan and van den Broeke, Michiel R. and Wouters, Bert and Kuipers Munneke, Peter and Kj{\ae}r, Kurt H.} } @article {oct, title = {Sensitivity of Pine Island Glacier to observed ocean forcing}, journal = {Geophysical Research Letters}, volume = {43}, year = {2016}, month = {oct}, pages = {10,817{\textendash}10,825}, abstract = {{\textcopyright}2016. American Geophysical Union. All Rights Reserved.We present subannual observations (2009{\textendash}2014) of a major West Antarctic glacier (Pine Island Glacier) and the neighboring ocean. Ongoing glacier retreat and accelerated ice flow were likely triggered a few decades ago by increased ocean-induced thinning, which may have initiated marine ice sheet instability. Following a subsequent 60{\%} drop in ocean heat content from early 2012 to late 2013, ice flow slowed, but by {\textless} 4{\%}, with flow recovering as the ocean warmed to prior temperatures. During this cold-ocean period, the evolving glacier-bed/ice shelf system was also in a geometry favorable to stabilization. However, despite a minor, temporary decrease in ice discharge, the basin-wide thinning signal did not change. Thus, as predicted by theory, once marine ice sheet instability is underway, a single transient high-amplitude ocean cooling has only a relatively minor effect on ice flow. The long-term effects of ocean temperature variability on ice flow, however, are not yet known.}, keywords = {glacier-ocean interactions, Ice Dynamics, ice shelves, ice streams, marine ice sheet instability}, issn = {00948276}, doi = {10.1002/2016GL070500}, url = {http://doi.wiley.com/10.1002/2016GL070500}, author = {Christianson, Knut and Bushuk, Mitchell and Dutrieux, Pierre and Parizek, Byron R. and Joughin, Ian R. and Alley, Richard B. and Shean, David E. and Abrahamsen, E. Povl and Anandakrishnan, Sridhar and Heywood, Karen J. and Kim, Tae-Wan and Lee, Sang Hoon and Nicholls, Keith and Stanton, Tim and Truffer, Martin and Webber, Benjamin G. M. and Jenkins, Adrian and Jacobs, Stan and Bindschadler, Robert and Holland, David M.} } @article {298, title = {Stable finite volume element schemes for the shallow ice approximation}, journal = {Journal of Glaciology}, volume = {62}, year = {2016}, pages = {230{\textendash}242}, doi = {10.1017/jog.2015.3}, author = {E. Bueler} } @article {MacGregor2016a, title = {{A synthesis of the basal thermal state of the Greenland Ice Sheet}}, journal = {Journal of Geophysical Research: Earth Surface}, year = {2016}, month = {jul}, issn = {21699003}, url = {http://doi.wiley.com/10.1002/2015JF003803}, author = {MacGregor, Joseph A. and Fahnestock, Mark A. and Catania, Ginny A. and Aschwanden, Andy and Clow, Gary D. and Colgan, William T. and Gogineni, S. Prasad and Morlighem, Mathieu and Nowicki, Sophie M. J. and Paden, John D. and Price, Stephen F. and Seroussi, Helene} } @article {348, title = {The taphonomy of human remains in a glacial environment}, journal = {Forensic Science International}, volume = {261}, year = {2016}, pages = {161.e1{\textendash}161.e8}, abstract = {A glacial environment is a unique setting that can alter human remains in characteristic ways. This study describes glacial dynamics and how glaciers can be understood as taphonomic agents. Using a case study of human remains recovered from Colony Glacier, Alaska, a glacial taphonomic signature is outlined that includes: (1) movement of remains, (2) dispersal of remains, (3) altered bone margins, (4) splitting of skeletal elements, and (5) extensive soft tissue preservation and adipocere formation. As global glacier area is declining in the current climate, there is the potential for more materials of archaeological and medicolegal significance to be exposed. It is therefore important for the forensic anthropologist to have an idea of the taphonomy in this setting and to be able to differentiate glacial effects from other taphonomic agents.}, keywords = {Forensic anthropology, Glacial dynamics, Glacial movement, Glacial taphonomy}, issn = {18726283}, doi = {10.1016/j.forsciint.2016.01.027}, url = {http://dx.doi.org/10.1016/j.forsciint.2016.01.027}, author = {Pilloud, Marin A. and Megyesi, Mary S. and Truffer, Martin and Congram, Derek} } @article {Truffer2016, title = {{Where Glaciers Meet Water: Subaqueous Melt and its Relevance to Glaciers in Various Settings}}, journal = {Reviews of Geophysics}, year = {2016}, pages = {n/a{\textendash}n/a}, keywords = {10.1002/2015RG000494 and glaciers, calving, melt, ocean}, issn = {87551209}, doi = {10.1002/2015RG000494}, url = {http://doi.wiley.com/10.1002/2015RG000494}, author = {Truffer, M. and Motyka, Roman} } @article {283, title = {Derivation and analysis of a complete modern-date glacier inventory for Alaska and northwest Canada}, journal = {Journal of Glaciology}, volume = {61}, year = {2015}, pages = {403}, author = {Kienholz, Christian and Herreid, Sam and Rich, J and Arendt, A and Hock, R and Burgess, E} } @article {351, title = {Dynamic jamming of iceberg-choked fjords}, journal = {Geophys. Res. Lett.}, volume = {42}, year = {2015}, pages = {1122{\textendash}1129}, keywords = {10.1002/2014GL062715 and glaciers, calving, icebergs, jamming}, issn = {00948276}, doi = {10.1002/2014GL062715}, author = {Peters, I and Amundson, J. M. and Cassotto, R and Fahnestock, M and Darnell, K and Truffer, M. and Zhang, W.} } @article {282, title = {End-of-winter snow depth variability on glaciers in Alaska}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {120}, year = {2015}, pages = {1530{\textendash}1550}, author = {McGrath, Daniel and Sass, Louis and O{\textquoteright}Neel, Shad and Arendt, Anthony and Wolken, Gabriel and Gusmeroli, Alessio and Kienholz, Christian and McNeil, Christopher} } @article {Khan2015, title = {{Greenland ice sheet mass balance}}, journal = {Reports on Progress in Physics}, volume = {78}, number = {46801}, year = {2015}, pages = {26}, publisher = {IOP Publishing}, abstract = {Mass balance equation for glaciers; areal distribution and ice volumes; estimates of actual mass balance; loss by calving of icebergs; hydrological budget for Greenland; and temporal variations of Greenland mass balance are examined.}, doi = {10.1088/0034-4885/78/4/046801}, url = {http://dx.doi.org/10.1088/0034-4885/78/4/046801}, author = {Khan, Shfaqat A. and Aschwanden, Andy and Bj{\o}rk, Anders A and Whar, John and Kjeldsen, Kristian K. and Kj{\ae}r, Kurt H.} } @article {277, title = {Mapping snow depth from manned aircraft on landscape scales at centimeter resolution using structure-from-motion photogrammetry}, journal = {The Cryosphere}, volume = {9}, year = {2015}, pages = {1445{\textendash}1463}, doi = {10.5194/tc-9-1445-2015}, url = {http://www.the-cryosphere.net/9/1445/2015/}, author = {Nolan, M. and Larsen, C. F. and Sturm, M.} } @article {272, title = {Mass-conserving subglacial hydrology in the Parallel Ice Sheet Model version 0.6}, journal = {Geoscientific Model Development}, volume = {8}, year = {2015}, pages = {1613{\textendash}1635}, doi = {10.5194/gmd-8-1613-2015}, url = {http://www.geosci-model-dev.net/8/1613/2015/}, author = {E. Bueler and van Pelt, W.} } @article {300, title = {A new model for global glacier change and sea-level rise}, journal = {Frontiers in Earth Science}, volume = {3}, year = {2015}, pages = {54}, abstract = {The anticipated retreat of glaciers around the globe will pose far-reaching challenges to the management of fresh water resources and significantly contribute to sea-level rise within the coming decades. Here, we present a new model for calculating the 21st century mass changes of all glaciers on Earth outside the ice sheets. The Global Glacier Evolution Model (GloGEM) includes mass loss due to frontal ablation at marine-terminating glacier fronts and accounts for glacier advance/retreat and surface Elevation changes. Simulations are driven with monthly near-surface air temperature and precipitation from 14 Global Circulation Models forced by the RCP2.6, RCP4.5 and RCP8.5 emission scenarios. Depending on the scenario, the model yields a global glacier volume loss of 25-48\% between 2010 and 2100. For calculating glacier contribution to sea-level rise, we account for ice located below sea-level presently displacing ocean water. This effect reduces glacier contribution by 11-14\%, so that our model predicts a sea-level equivalent (multi-model mean +-1 standard deviation) of 79+-24 mm (RCP2.6), 108+-28 mm (RCP4.5) and 157+-31 mm (RCP8.5). Mass losses by frontal ablation account for 10\% of total ablation globally, and up to 30\% regionally. Regional equilibrium line altitudes are projected to rise by 100-800 m until 2100, but the effect on ice wastage depends on initial glacier hypsometries.}, issn = {2296-6463}, doi = {10.3389/feart.2015.00054}, url = {http://journal.frontiersin.org/article/10.3389/feart.2015.00054}, author = {Huss, Matthias and Hock, Regine} } @article {MacGregor2015b, title = {{Radar attenuation and temperature within the Greenland Ice Sheet}}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {120}, number = {6}, year = {2015}, month = {jun}, pages = {983{\textendash}1008}, issn = {21699003}, doi = {10.1002/2014JF003418}, url = {http://doi.wiley.com/10.1002/2014JF003418}, author = {MacGregor, Joseph A. and Li, Jilu and Paden, John D and Catania, Ginny a and Clow, Gary D and Fahnestock, Mark A and Gogineni, S Prasad and Grimm, Robert E and Morlighem, Mathieu and Nandi, Soumyaroop and Seroussi, Helene and Stillman, David E} } @article {MacGregor2015, title = {{Radiostratigraphy and age structure of the Greenland Ice Sheet}}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {120}, year = {2015}, pages = {212{\textendash}241}, keywords = {10.1002/2014JF003215 and Greenland Ice Sheet, ice core, ice-penetrating dynamics, ice-sheet dynamics}, issn = {21699003}, doi = {10.1002/2014JF003215}, url = {http://doi.wiley.com/10.1002/2014JF003215}, author = {MacGregor, Joseph A. and Fahnestock, Mark A. and Catania, Ginny A. and Paden, John D and Prasad Gogineni, S. and Young, S Keith and Rybarski, Susan C and Mabrey, Alexandria N and Wagman, Benjamin M and Morlighem, Mathieu} } @article {Fahnestock2015, title = {{Rapid large-area mapping of ice flow using Landsat 8}}, journal = {Remote Sensing of Environment}, year = {2015}, publisher = {The Authors}, abstract = {We report on the maturation of optical satellite-image-based ice velocity mapping over the ice sheets and large glacierized areas, enabled by the high radiometric resolution and internal geometric accuracy of Landsat 8{\textquoteright}s Operational Land Imager (OLI). Detailed large-area single-season mosaics and time-series maps of ice flow were created using data spanning June 2013 to June 2015. The 12-bit radiometric quantization and 15-m pixel scale resolution of OLI band 8 enable displacement tracking of subtle snow-drift patterns on ice sheet surfaces at $\sim$. 1. m precision. Ice sheet and snowfield snow-drift features persist for typically 16 to 64. days, and up to 432. days, depending primarily on snow accumulation rates. This results in spatially continuous mapping of ice flow, extending the mapping capability beyond crevassed areas. Our method uses image chip cross-correlation and sub-pixel peak-fitting in matching Landsat path/row pairs. High-pass filtering is applied to the imagery to enhance local surface texture. The current high image acquisition rates of Landsat 8 (725 scenes per day globally) reduces the impact of high cloudiness in polar and mountain terrain and allows rapid compilation of large areas, or dense temporal coverage of seasonal ice flow variations. The results rival the coverage and accuracy of interferometric Synthetic Aperture Radar (InSAR) mapping.}, keywords = {Antarctica, glaciers, Greenland, Ice flow, Landsat, Remote sensing}, issn = {00344257}, doi = {10.1016/j.rse.2015.11.023}, url = {http://dx.doi.org/10.1016/j.rse.2015.11.023}, author = {Fahnestock, Mark and Scambos, Ted and Moon, Twila and Gardner, Alex and Haran, Terry and Klinger, Marin} } @article {2015/10/29, title = {Recent Arctic tundra fire initiates widespread thermokarst development}, journal = {Scientific Reports}, volume = {5}, year = {2015}, month = {2015/10/29}, pages = {15865 - }, url = {http://dx.doi.org/10.1038/srep15865}, author = {Jones, Benjamin M. and Grosse, Guido and Arp, Christopher D. and Miller, Eric and Liu, Lin and Hayes, Daniel J. and Larsen, Christopher F.} } @article {Jun-06-2017, title = {The response of fabric variations to simple shear and migration recrystallization}, journal = {Journal of Glaciology}, volume = {61}, year = {2015}, month = {Jun-06-2017}, pages = {537 - 550}, abstract = {The observable microstructures in ice are the result of many dynamic and competing processes. These processes are influenced by climate variables in the firn. Layers deposited in different climate regimes may show variations in fabric which can persist deep into the ice sheet; fabric may {\textquoteleft}remember{\textquoteright} these past climate regimes. We model the evolution of fabric variations below the firn{\textendash}ice transition and show that the addition of shear to compressive-stress regimes preserves the modeled fabric variations longer than compression-only regimes, because shear drives a positive feedback between crystal rotation and deformation. Even without shear, the modeled ice retains memory of the fabric variation for ~200 ka in typical polar ice-sheet conditions. Our model shows that temperature affects how long the fabric variation is preserved, but only affects the strain-integrated fabric evolution profile when comparing results straddling the thermal-activation-energy threshold (~{\textendash}10{\textdegree}C). Even at high temperatures, migration recrystallization does not eliminate the modeled fabric{\textquoteright}s memory under most conditions. High levels of nearest-neighbor interactions will, however, eliminate the modeled fabric{\textquoteright}s memory more quickly than low levels of nearest-neighbor interactions. Ultimately, our model predicts that fabrics will retain memory of past climatic variations when subject to a wide variety of conditions found in polar ice sheets.}, issn = {00221430}, doi = {10.3189/2015JoG14J156}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=61\&issue=227\&spage=537http://www.ingentaconnect.com/content/igsoc/jog/2015/00000061/00000227/art00011}, author = {Kennedy, Joseph H. and Pettit, Erin C.} } @article {253, title = {Run-away thinning of the low elevation {Yakutat Glacier} and its sensitivity to climate change}, journal = {Journal of Glaciology}, volume = {61}, year = {2015}, doi = {10.3189/2015JoG14J125}, author = {Truessel, Barbara and Martin Truffer and Regine Hock and Roman Motyka and Matthias Huss and Jing Zhang} } @article {281, title = {Satellite observations show no net change in the percentage of supraglacial debris-covered area in northern Pakistan from 1977 to 2014}, journal = {Journal of Glaciology}, volume = {61}, year = {2015}, pages = {524{\textendash}536}, author = {Herreid, Sam and Pellicciotti, Francesca and Ayala, Alvaro and Chesnokova, Anna and Kienholz, Christian and Shea, Joseph and Shrestha, Arun} } @article {350, title = {Seasonal and interannual variations in ice melange and its impact on terminus stability, Jakobshavn Isbr{\ae}, Greenland}, journal = {Journal of Glaciology}, volume = {61}, year = {2015}, pages = {76{\textendash}88}, keywords = {arctic glaciology, calving, ice, ocean interactions, Remote sensing, sea-ice dynamics}, issn = {00221430}, doi = {10.3189/2015JoG13J235}, author = {Cassotto, Ryan and Fahnestock, Mark and Amundson, Jason M. and Truffer, Martin and Joughin, Ian} } @article {274, title = {Subglacial discharge at tidewater glaciers revealed by seismic tremor}, journal = {Geophysical Research Letters}, year = {2015}, author = {Bartholomaus, Timothy C and Amundson, Jason M and Walter, Jacob I and O{\textquoteright}Neel, Shad and West, Michael E and Chris F. Larsen} } @article {273, title = {Surface melt dominates Alaska glacier mass balance}, journal = {Geophysical Research Letters}, volume = {42}, year = {2015}, pages = {5902{\textendash}5908}, author = {Chris F. Larsen and Burgess, E and Arendt, AA and O{\textquoteright}Neel, S and Johnson, AJ and Kienholz, C} } @article {289, title = {Tidal and seasonal variations in calving flux observed with passive seismology}, journal = {Journal of Geophysical Research: Earth Surface}, year = {2015}, author = {Bartholomaus, Timothy C and Larsen, Christopher F and West, Michael E and O{\textquoteright}Neel, Shad and Pettit, Erin C and Truffer, Martin} } @article {05/2015, title = {Triggered Seismic Events along the Eastern Denali Fault in Northwest Canada Following the 2012 Mw 7.8 Haida Gwaii, 2013 Mw 7.5 Craig, and Two Mw>8.5 Teleseismic Earthquakes}, journal = {Bulletin of the Seismological Society of America}, volume = {105}, year = {2015}, month = {05/2015}, chapter = {1165}, abstract = {We conduct a systematic search for remotely triggered seismic activity along the eastern Denali fault (EDF) in northwest Canada, an intraplate strike-slip region. We examine 19 distant earthquakes recorded by nine broadband stations in the Canadian National Seismograph Network and find that the 2012 Mw 7.8 Haida Gwaii and 2013 Mw 7.5 Craig, Alaska, earthquakes triggered long duration (>10 s), emergent tremor-like signals near the southeastern portion of the EDF. In both cases, tremor coincides with the peak transverse velocities, consistent with Love-wave triggering on right-lateral strike-slip faults. The 2011 Mw 9.0 Tohoku-Oki and 2012 Mw 8.6 Indian Ocean earthquakes possibly triggered tremor signals, although we were unable to locate those sources. In addition, we also identify many short-duration (<5 s) bursts that were repeatedly triggered by the Rayleigh waves of the 2012 Mw 7.8 Haida Gwaii earthquake. Although we were unable to precisely locate the short-duration (<5 s) events, they appear to be radiating from the direction of the Klutlan Glacier and from a belt of shallow historical seismicity at the eastern flank of the Wrangell{\textendash}St. Elias mountain range. The fact that these events were triggered solely by the Rayleigh waves suggests a different source mechanism as compared with triggered tremor observed along the EDF and other plate boundary regions. }, doi = {10.1785/0120140156}, url = {http://www.bssaonline.org/content/early/2015/04/08/0120140156.abstract}, author = {Chastity Aiken and Jessica Zimmerman Mejia} } @article {301, title = {Variations in Alaska tidewater glacier frontal ablation, 1985{\textendash}2013}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {120}, year = {2015}, pages = {120{\textendash}136}, keywords = {frontal ablation, glacier dynamics, glaciers, ice thickness}, issn = {2169-9011}, doi = {10.1002/2014JF003276}, url = {http://dx.doi.org/10.1002/2014JF003276}, author = {McNabb, R. W. and Hock, R. and Huss, M.} } @article {Das2014, title = {{21st-century increase in glacier mass loss in the Wrangell Mountains, Alaska, USA, from airborne laser altimetry and satellite stereo imagery}}, journal = {J. Glaciol.}, volume = {60}, number = {220}, year = {2014}, pages = {283{\textendash}293}, keywords = {glacier mass balance, ice and climate}, issn = {00221430}, doi = {10.3189/2014JoG13J119}, url = {http://www.igsoc.org/journal/60/220/j13J119.html}, author = {Das, Indrani and Hock, Regine and Berthier, Etienne and Lingle, Craig S.} } @article {275, title = {Alaska National Park glaciers: what do they tell us about climate change?}, journal = {Alaska Park Science}, volume = {12}, year = {2014}, pages = {18{\textendash}25}, author = {Loso, M.G. and Arendt, A. and Chris F. Larsen and Murphy, N. and Rich, J.} } @article {Jan-02-2014, title = {Alaska tidewater glacier terminus positions, 1948-2012}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {119}, year = {2014}, month = {Jan-02-2014}, pages = {153 - 167}, doi = {10.1002/jgrf.v119.210.1002/2013JF002915}, url = {http://doi.wiley.com/10.1002/jgrf.v119.2http://doi.wiley.com/10.1002/2013JF002915}, author = {R ~W McNabb and Hock, R.} } @article {rebesco2014boundary, title = {Boundary condition of grounding lines prior to collapse, Larsen-B Ice Shelf, Antarctica}, journal = {Science}, volume = {345}, number = {6202}, year = {2014}, pages = {1354{\textendash}1358}, publisher = {American Association for the Advancement of Science}, author = {Rebesco, M and Domack, E and Zgur, F and Lavoie, C and Leventer, A and Brachfeld, S and Willmott, V and Halverson, G and Truffer, M and Scambos, T and Pettit, Erin C} } @article {247, title = {Correspondence: Extending the lumped subglacial{\textendash}englacial hydrology model of Bartholomaus and others (2011)}, journal = {J. Glaciol.}, volume = {60}, year = {2014}, pages = {808{\textendash}810}, doi = {10.3189/2014JoG14J075}, url = {http://www.igsoc.org/journal/60/222/t14j075.html}, author = {E. Bueler} } @article {205, title = {Coupled ice sheet{\textendash}climate modeling under glacial and pre-industrial boundary conditions}, journal = {Climate of the Past}, volume = {10}, year = {2014}, pages = {1817-1836}, chapter = {1817}, abstract = {In the standard Paleoclimate Modelling Intercomparison Project (PMIP) experiments, the Last Glacial Maximum (LGM) is modeled in quasi-equilibrium with atmosphere{\textendash}ocean{\textendash}vegetation general circulation models (AOVGCMs) with prescribed ice sheets. This can lead to inconsistencies between the modeled climate and ice sheets. One way to avoid this problem would be to model the ice sheets explicitly. Here, we present the first results from coupled ice sheet{\textendash}climate simulations for the pre-industrial times and the LGM. Our setup consists of the AOVGCM ECHAM5/MPIOM/LPJ bidirectionally coupled with the Parallel Ice Sheet Model (PISM) covering the Northern Hemisphere. The results of the pre-industrial and LGM simulations agree reasonably well with reconstructions and observations. This shows that the model system adequately represents large, non-linear climate perturbations. A large part of the drainage of the ice sheets occurs in ice streams. Most modeled ice stream systems show recurring surges as internal oscillations. The Hudson Strait Ice Stream surges with an ice volume equivalent to about 5 m sea level and a recurrence interval of about 7000 yr. This is in agreement with basic expectations for Heinrich events. Under LGM boundary conditions, different ice sheet configurations imply different locations of deep water formation. }, doi = {10.5194/cp-10-1817-2014}, url = {http://www.clim-past.net/10/1817/2014/cp-10-1817-2014.html}, author = {Ziemen, F. A. and Rodehacke, C. B. and Mikolajewicz, U.} } @article {248, title = {The effect of climate forcing on numerical simulations of the Cordilleran ice sheet at the Last Glacial Maximum}, journal = {The Cryosphere}, volume = {8}, year = {2014}, pages = {1087{\textendash}1103}, doi = {10.5194/tc-8-1087-2014}, url = {http://www.the-cryosphere.net/8/1087/2014/}, author = {Seguinot, J. and Khroulev, C. and Rogozhina, I. and Stroeven, A. P. and Zhang, Q.} } @article {250, title = {An exact solution for a steady, flow-line marine ice sheet}, journal = {J.~Glaciol.}, volume = {60}, year = {2014}, pages = {1117{\textendash}1125}, doi = {10.3189/2014JoG14J066}, author = {E. Bueler} } @article {279, title = {Glacier area and length changes in Norway from repeat inventories}, journal = {The Cryosphere}, volume = {8}, year = {2014}, pages = {1885{\textendash}1903}, author = {Winsvold, S. H. and Andreassen, L. M. and Kienholz, C.} } @article {280, title = {Glacier changes in the Karakoram region mapped by multimission satellite imagery}, journal = {The Cryosphere}, volume = {8}, year = {2014}, pages = {977{\textendash}989}, author = {Rankl, Melanie and Kienholz, C and Braun, M} } @article {tc-8-1497-2014, title = {Glacier dynamics at Helheim and Kangerdlugssuaq glaciers, southeast Greenland, since the Little Ice Age}, journal = {The Cryosphere}, volume = {8}, number = {4}, year = {2014}, pages = {1497{\textendash}1507}, doi = {10.5194/tc-8-1497-2014}, url = {http://www.the-cryosphere.net/8/1497/2014/}, author = {Khan, S. A. and Kjeldsen, K. K. and Kj{\ae}r, K. H. and Bevan, S. and Luckman, A. and Aschwanden, A. and Bj{\o}rk, A. A. and Korsgaard, N. J. and Box, J. E. and Van Den Broeke, M. and van Dam, T. M. and Fitzner, A.} } @inbook {352, title = {Glacier Surges}, booktitle = {Snow and Ice-Related Hazards, Risks, and Disasters}, year = {2014}, abstract = {{\textcopyright} 2015 Elsevier Inc. All rights reserved.Surge-type glaciers periodically undergo large flow acceleration after extended quiescent phases of slow movement, usually accompanied by terminus advance. Such glaciers are relatively rare but occur in many of the world{\textquoteright}s glacierized areas. High water pressures and extreme basal sliding are obvious characteristics but key questions concerning this, usually spectacular phenomenon, remain open. Why are glaciers in some regions surge-type but not in others, what sort of "memory" lets glaciers surge again and again, what is the influence of climate, geology, and topography? Besides their scientific interest, glacier surges can also be a threat to humans, especially in connection with rapidly forming lakes and their sudden outbursts. Cases of hazard- and disaster-related glacier surges are described from the Pamirs, the Andes, the Italian Alps, and Alaska.}, keywords = {Flow instabilities, Ice dammed lakes, Outburst floods, Pipeline safety, River blocking, surge-type glaciers}, isbn = {9780123964731}, doi = {10.1016/B978-0-12-394849-6.00013-5}, author = {Harrison, W.D. and Osipova, G.B. and Nosenko, G.A. and Espizua, L. and K{\"a}{\"a}b, A. and L Fischer and Huggel, C. and Craw Burns, P.A. and Truffer, M. and Lai, A.W.} } @inbook {256, title = {Glaciers and Climate Change}, booktitle = {Handbook of Global Environmental Pollution: Global Environmental Change}, year = {2014}, pages = {205{\textendash}210}, publisher = {Springer}, organization = {Springer}, chapter = {Glaciers and Climate Change}, doi = {10.1007/978-94-007-5784-4_130}, author = {Regine Hock}, editor = {B. Freedman} } @article {259, title = {Glaciers in the Earth{\textquoteright}s Hydrological Cycle: Assessments of Glacier Mass and Runoff Changes on Global and Regional Scales}, journal = {Surveys in Geophysics}, volume = {35}, year = {2014}, pages = {813-837}, keywords = {Glacier projections, glacier runoff, glaciers, mass balance, Mass-balance observations, Modeling, Sea-level rise}, issn = {0169-3298}, doi = {10.1007/s10712-013-9262-y}, url = {http://dx.doi.org/10.1007/s10712-013-9262-y}, author = {Radi{\'c}, Valentina and Hock, Regine} } @article {257, title = {Global response of glacier runoff to twenty-first century climate change}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {119}, year = {2014}, pages = {717{\textendash}730}, keywords = {climate change, glacier mass balance, glacier runoff}, issn = {2169-9011}, doi = {10.1002/2013JF002931}, url = {http://dx.doi.org/10.1002/2013JF002931}, author = {Bliss, Andrew and Hock, Regine and Radi{\'c}, Valentina} } @article {239, title = {Helicopter borne radar imaging of snow cover on and around glaciers in {A}laska}, journal = {Annals of Glaciology}, volume = {55}, year = {2014}, pages = {78-88}, doi = {10.3189/2014AoG67A029}, author = {Gusmeroli, A. and Wolken, G. and Arendt, A.} } @article {353, title = {Ice Thickness Measurements on the Harding Icefield , Kenai Peninsula , Alaska}, year = {2014}, author = {Truffer, Martin} } @article {pettit2014influence, title = {Influence of debris-rich basal ice on flow of a polar glacier}, journal = {Journal of Glaciology}, volume = {60}, number = {223}, year = {2014}, pages = {989{\textendash}1006}, publisher = {International Glaciological Society}, author = {Pettit, Erin C and Whorton, Erin N and Waddington, Edwin D and Sletten, Ronald S} } @article {220, title = {A new method for deriving glacier centerlines applied to glaciers in Alaska and northwest Canada}, journal = {The Cryosphere}, volume = {8}, year = {2014}, pages = {503{\textendash}519}, doi = {10.5194/tc-8-503-2014}, url = {http://www.the-cryosphere.net/8/503/2014/}, author = {Kienholz, C. and Rich, J. L. and Arendt, A. A. and Hock, R.} } @article {355, title = {Quantifying velocity response to ocean tides and calving near the terminus of Jakobshavn Isbr{\ae}, Greenland}, journal = {Journal of Glaciology}, volume = {60}, year = {2014}, pages = {609{\textendash}621}, keywords = {calving, glacier fluctuations, ice, ocean interactions}, issn = {00221430}, doi = {10.3189/2014JoG13J130}, url = {http://www.igsoc.org/journal/60/222/t13J130.html}, author = {Podrasky, David and Truffer, Martin and L{\"u}thi, Martin and Fahnestock, Mark} } @article {240, title = {The Randolph Glacier Inventory: a globally complete inventory of glaciers}, volume = {60}, year = {2014}, pages = {537 - 552}, doi = {10.3189/2014JoG13J176}, author = {Pfeffer, W.T. and Arendt, A. and Bliss, A. and Bolch, T. and Cogley, G. and Gardner, A. and Hagen, J-O., and Hock, R. and Kaser, G and Kienholz, C. and Miles, E. and Moholdt, G. and M{\"o}lg, N. and Paul, F. and Radi{\'c}, V. and Rastner, P. and Raup, B. and Rich, J. and Sharp, M.} } @article {Feldmannetal2014, title = {Resolution-dependent performance of grounding line motion in a shallow model compared to a full-{S}tokes model according to the {MISMIP3d} intercomparison}, journal = {J. Glaciol.}, volume = {60}, number = {220}, year = {2014}, pages = {353{\textendash}360}, doi = {10.3189/2014JoG13J093}, author = {Feldmann, J. and Albrecht, T. and Khroulev, C. and Pattyn, F. and Levermann, A.} } @article {Adalgeirsdottir2014, title = {{Role of model initialization for projections of 21st-century Greenland ice sheet mass loss}}, journal = {Journal of Glaciology}, volume = {60}, number = {222}, year = {2014}, pages = {782{\textendash}794}, keywords = {ice and climate, ice-sheet modeling}, issn = {00221430}, doi = {10.3189/2014JoG13J202}, url = {http://www.igsoc.org/journal/60/222/t13j202.html}, author = {A{\dh}algeirsd{\'o}ttir, Gu{\dh}finna and Aschwanden, Andy and Khroulev, Constantine and Boberg, Frederik and Mottram, Ruth and Lucas-Picher, P.} } @article {354, title = {Surface Drifters Track the Fate of Greenland Ice Sheet Meltwater}, journal = {Eos Trans. AGU}, volume = {95}, year = {2014}, pages = {237{\textendash}239}, doi = {10.1002/2014EO260002}, author = {Hauri, C. and Truffer, M. and Winsor, P. and Lennert, K.} } @article {255, title = {Surface velocity and mass balance of Livingston Island ice cap, Antarctica}, journal = {The Cryosphere}, volume = {8}, year = {2014}, pages = {1807{\textendash}1823}, doi = {10.5194/tc-8-1807-2014}, url = {http://www.the-cryosphere.net/8/1807/2014/}, author = {Osmanoglu, B. and Navarro, F. J. and Hock, R. and Braun, M. and Corcuera, M. I.} } @article {fischer_system_2014, title = {A system of conservative regridding for ice{\textendash}atmosphere coupling in a {General} {Circulation} {Model} ({GCM})}, journal = {Geoscientific Model Development}, volume = {7}, number = {3}, year = {2014}, pages = {883{\textendash}907}, abstract = {The method of elevation classes, in which the ice surface model is run at multiple elevations within each grid cell, has proven to be a useful way for a low-resolution atmosphere inside a general circulation model (GCM) to produce high-resolution downscaled surface mass balance fields for use in one-way studies coupling atmospheres and ice flow models. Past uses of elevation classes have failed to conserve mass and energy because the transformation used to regrid to the atmosphere was inconsistent with the transformation used to downscale to the ice model. This would cause problems for two-way coupling.}, keywords = {1911-UW, Regridding}, issn = {1991-9603}, doi = {10.5194/gmd-7-883-2014}, url = {https://www.geosci-model-dev.net/7/883/2014/}, author = {Fischer, R. and Nowicki, S. and Kelley, M. and Schmidt, G. A.} } @article {254, title = {Variations in {Alaska} tidewater glacier frontal ablation, 1985{\textendash}2013}, journal = {Journal of Geophysical Research: Earth Surface}, year = {2014}, keywords = {frontal ablation, glacier dynamics, ice thickness}, issn = {2169-9011}, doi = {10.1002/2014JF003276}, url = {http://dx.doi.org/10.1002/2014JF003276}, author = {McNabb, R. W. and Hock, R. and Huss, M.} } @article {166, title = {Active tectonics of the St. Elias orogen, Alaska, observed with GPS measurements}, journal = {Journal of Geophysical Research: Solid Earth}, year = {2013}, pages = {n/a{\textendash}n/a}, abstract = {We use data from campaign and continuous GPS sites in southeast and south central Alaska to constrain a regional tectonic block model for the St. Elias orogen. Active tectonic deformation in the orogen is dominated by the effects of the collision of the Yakutat block with southern Alaska. Our results indicate that ~37 mm/yr of convergence is accommodated along a relatively narrow belt of N-NW dipping thrust faults in the eastern half of the orogen, with the present-day deformation front running through Icy Bay and beneath the Malaspina Glacier. Near the Bering Glacier, the collisional thrust fault regime transitions into a broad, northwest dipping d{\'e}collement as the Yakutat block basement begins to subduct beneath the counterclockwise rotating Elias block. The location of this transition aligns with the Gulf of Alaska shear zone, implying that the Pacific plate is fragmenting in response to the Yakutat collision. Our model indicates that the Bering Glacier region is undergoing internal deformation and could correspond to the final stage of offscraping and accretion of sediments from the Yakutat block prior to subduction. Predicted block motions at the western edge of the orogen suggest that the crust is laterally escaping along the Aleutian fore arc.}, keywords = {Alaska, geodesy, St. Elias orogen, tectonics, Yakutat block}, issn = {2169-9356}, doi = {10.1002/jgrb.50341}, url = {http://dx.doi.org/10.1002/jgrb.50341}, author = {Elliott, Julie and Jeffrey T. Freymueller and Chris F. Larsen} } @article {135, title = {Analysis of a GRACE global mascon solution for Gulf of Alaska glaciers}, journal = {Journal of Glaciology}, volume = {59}, year = {2013}, pages = {913-924}, doi = {10.3189/2013JoG12J197}, author = {Anthony A. Arendt and Scott B Luthcke and Alex S. Gardner and Shad O'Neel and D. Hill and Geir Moholdt and Waleed Abdalati} } @article {124, title = {Antarctica, Greenland and Gulf of Alaska land-ice evolution from an iterated GRACE global mascon solution}, journal = {Journal of Glaciology}, volume = {59}, year = {2013}, pages = {613{\textendash}631}, doi = {10.3189/2013JoG12J147}, author = {Scott B Luthcke and Sabaka, TJ and Loomis, BD and Anthony A. Arendt and J J McCarthy and Camp, J} } @article {2013/08/01, title = {Challenges to Understanding the Dynamic Response of Greenland{\textquoteright}s Marine Terminating Glaciers to Oceanic and Atmospheric Forcing}, journal = {Bulletin of the American Meteorological Society}, volume = {94}, year = {2013}, month = {2013/08/01}, pages = {1131 - 1144}, doi = {10.1175/BAMS-D-12-00100.1}, url = {http://dx.doi.org/10.1175/BAMS-D-12-00100.1}, author = {Straneo, Fiammetta and Heimbach, Patrick and Sergienko, Olga and Hamilton, Gordon and Catania, Ginny and Griffies, Stephen and Hallberg, Robert and Jenkins, Adrian and Joughin, Ian and Motyka, Roman and Pfeffer, W. Tad and Stephen F. Price and Eric Rignot and Scambos, Ted and Martin Truffer and Vieli, Andreas} } @article {11/2013, title = {Changing basal conditions during the speed-up of Jakobshavn Isbr{\ae}, Greenland}, journal = {The Cryosphere}, volume = {7}, year = {2013}, month = {11/2013}, pages = {1679{\textendash}1692}, author = {Habermann, M and Martin Truffer and Maxwell, D} } @article {sep, title = {Channelized ice melting in the ocean boundary layer beneath Pine Island Glacier, Antarctica.}, journal = {Science (New York, N.Y.)}, volume = {341}, year = {2013}, month = {sep}, pages = {1236{\textendash}9}, abstract = {Ice shelves play a key role in the mass balance of the Antarctic ice sheets by buttressing their seaward-flowing outlet glaciers; however, they are exposed to the underlying ocean and may weaken if ocean thermal forcing increases. An expedition to the ice shelf of the remote Pine Island Glacier, a major outlet of the West Antarctic Ice Sheet that has rapidly thinned and accelerated in recent decades, has been completed. Observations from geophysical surveys and long-term oceanographic instruments deployed down bore holes into the ocean cavity reveal a buoyancy-driven boundary layer within a basal channel that melts the channel apex by 0.06 meter per day, with near-zero melt rates along the flanks of the channel. A complex pattern of such channels is visible throughout the Pine Island Glacier shelf.}, keywords = {Antarctic Regions, Freezing, Ice Cover, Oceans and Seas}, issn = {1095-9203}, doi = {10.1126/science.1239373}, url = {http://www.ncbi.nlm.nih.gov/pubmed/24031016}, author = {Stanton, T P and Shaw, W J and Truffer, M. and Corr, H F J and Peters, L E and Riverman, K L and Bindschadler, R and Holland, D M and Anandakrishnan, S} } @article {138, title = {Does calving matter? Evidence for significant submarine melt}, journal = {Earth and Planetary Science Letters}, volume = {380}, year = {2013}, pages = {21 - 30}, issn = {0012-821X}, doi = {http://dx.doi.org/10.1016/j.epsl.2013.08.014}, url = {http://www.sciencedirect.com/science/article/pii/S0012821X13004408}, author = {Timothy C. Bartholomaus and Chris F. Larsen and Shad O'Neel} } @article {83, title = {Estimating glacier snow accumulation from backward calculation of melt and snowline tracking}, journal = {Annals of Glaciology}, volume = {54}, year = {2013}, pages = {1}, doi = {10.3189/2012AoG62A083}, author = {Hulth, J. and DENBY, C.R. and Regine Hock} } @article {119, title = {The evolution of crystal fabric in ice sheets and its link to climate history}, journal = {Journal of Glaciology}, volume = {59}, year = {2013}, pages = {357-373}, abstract = {The evolution of preferred crystal-orientation fabrics is strongly sensitive to the initial fabric and texture. A perturbation in climate can induce variations in fabric and texture in the firn. Feedbacks between fabric evolution and ice deformation can enhance these variations through time and depth in an ice sheet. We model the evolution of fabric under vertical uniaxial compression and pure shear regimes typical of ice divides. Using an analytic anisotropic flow law applied to an aggregate of distinct ice crystals, the model evolves the fabric and includes parameterizations of crystal growth, polygonization and migration recrystallization. Stress and temperature history drive the fabric evolution. Using this model, we explore the evolution of a subtle variation in near-surface fabric using both constant applied stress and a stress-temperature history based on data from Taylor Dome, East Antarctica. Our model suggests that a subtle variation in fabric caused by climate perturbations will be preserved through time and depth in an ice sheet. The stress history and polygonization rate primarily control the magnitude of the preserved climate signal. These results offer the possibility of extracting information about past climate directly from ice fabrics.}, doi = {10.3189/2013JoG12J159}, url = {http://glacierstest.gi.alaska.edu/sites/default/files/bibfiles/t12J159.pdf}, author = {Joseph H Kennedy and Erin C Pettit and Di Prinzio, Carlos L} } @article {137, title = {Flow velocities of Alaskan glaciers}, journal = {Nat Commun}, volume = {4}, year = {2013}, doi = {10.1038/ncomms3146}, url = {http://dx.doi.org/10.1038/ncomms3146}, author = {Evan W. Burgess and Richard R. Forster and Chris F. Larsen} } @article {126, title = {Geodetic Mass Balance of Glaciers in the Central Brooks Range, Alaska, USA, from 1970 to 2001}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {45}, year = {2013}, pages = {29{\textendash}38}, doi = {10.1657/1938-4246-45.1.29}, author = {Geck, Jason and Regine Hock and Nolan, Matt} } @article {125, title = {Glaciers and ice caps (outside Greenland)}, year = {2013}, institution = { Bull. Amer. Meteor. Soc. 94(7), S143}, author = {G. J. Wolken and Martin J. Sharp and M-L. Geai and D. Burges and Anthony A. Arendt and Bert Wouters} } @article {133, title = {Hindcasting to measure ice sheet model sensitivity to initial states}, journal = {The Cryosphere}, volume = {7}, year = {2013}, pages = {1083{\textendash}1093}, author = {Andy Aschwanden and Gudfinna A{\dh}algeirsd{\'o}ttir and Constantine Khroulev} } @article {130, title = {Ice-sheet model sensitivities to environmental forcing and their use in projecting future sea-level (The SeaRISE Project)}, journal = {J. Glaciol}, volume = {59}, year = {2013}, pages = {195{\textendash}224}, author = {Robert A. Bindschadler and Nowicki, Sophie and Abe-Ouchi, Ayako and Andy Aschwanden and Choi, Hyeungu and Fastook, Jim and Granzow, Glen and Greve, Ralf and Gutowski, Gail and Herzfeld, Ute and others} } @article {SeariseGreenland2013, title = {{Insights into spatial sensitivities of ice mass response to environmental change from the SeaRISE ice sheet modeling project II: Greenland}}, journal = {J. Geophys. Res.}, volume = {118}, number = {2}, year = {2013}, month = {jun}, pages = {1025{\textendash}1044}, issn = {21699003}, doi = {10.1002/jgrf.20076}, url = {http://doi.wiley.com/10.1002/jgrf.20076}, author = {Nowicki, Sophie and Robert A. Bindschadler and Abe-Ouchi, Ayako and Andy Aschwanden and E. Bueler and Choi, Hyeungu and Fastook, Jim and Granzow, Glen and Greve, Ralf and Gutowski, Gail and Herzfeld, Ute and Jackson, Charles and Jesse V Johnson and Constantine Khroulev and Larour, Eric and Anders Levermann and Lipscomb, William H. and Maria A. Martin and Morlighem, Mathieu and Parizek, Byron R. and David Pollard and Stephen F. Price and Ren, Diandong and Eric Rignot and Fuyuki Saito and Tatsuru Sato and Seddik, Hakime and Seroussi, Helene and Takahashi, Kunio and Walker, Ryan and Wang, Wei Li} } @article {SeariseAntarctica2013, title = {{Insights into spatial sensitivities of ice mass response to environmental change from the SeaRISE ice sheet modeling project I: Antarctica}}, journal = {J. Geophys. Res.}, volume = {118}, number = {2}, year = {2013}, pages = {1002{\textendash}1024}, issn = {21699003}, doi = {10.1002/jgrf.20081}, url = {http://doi.wiley.com/10.1002/jgrf.20081}, author = {Nowicki, Sophie and Robert A. Bindschadler and Abe-Ouchi, Ayako and Andy Aschwanden and E. Bueler and Choi, Hyeungu and Fastook, Jim and Granzow, Glen and Greve, Ralf and Gutowski, Gail and Herzfeld, Ute and Jackson, Charles and Jesse V Johnson and Constantine Khroulev and Larour, Eric and Anders Levermann and Lipscomb, William H. and Maria A. Martin and Morlighem, Mathieu and Parizek, Byron R. and David Pollard and Stephen F. Price and Ren, Diandong and Eric Rignot and Fuyuki Saito and Tatsuru Sato and Seddik, Hakime and Seroussi, Helene and Takahashi, Kunio and Walker, Ryan and Wang, Wei Li} } @article {167, title = {Low-frequency radar sounding of temperate ice masses in Southern Alaska}, journal = {Geophysical Research Letters}, year = {2013}, pages = {n/a{\textendash}n/a}, abstract = {We present the Warm Ice Sounding Explorer (WISE), a low-frequency (2.5 MHz) radar for the sounding of temperate ice. WISE deployment in southern Alaska in 2008 and 2012 provides comprehensive measurements of glacier thickness, reveals deep valleys beneath glaciers and the full extent of zones grounded below sea level. The east branch of Columbia Glacier is deeper that its main branch and remains below sea level 20 km farther inland. Ice is 1000 m deep on Tazlina Glacier. On Bering glacier, two sills separate three deep bed depressions (>1200 m) that coincide with the dynamic balance lines during surges. The piedmont lobe of Malaspina Glacier and the lower reaches of Hubbard Glacier are entirely grounded below sea level 40 and 10 km, respectively, from their termini. Knowledge of ice thickness in these regions helps better understand their glacier dynamics, mass balance, and impact on sea level.}, keywords = {Alaska, bed topography, glaciology, mass balance, radar, thickness}, issn = {1944-8007}, doi = {10.1002/2013GL057452}, url = {http://dx.doi.org/10.1002/2013GL057452}, author = {Eric Rignot and Mouginot, J. and Chris F. Larsen and Gim, Y. and Kirchner, D.} } @article {120, title = {Mass balance in the Glacier Bay area of Alaska, USA, and British Columbia, Canada, 1995{\textendash}2011, using airborne laser altimetry}, journal = {Journal of Glaciology}, volume = {59}, year = {2013}, pages = {632{\textendash}648}, doi = {10.3189/2013JoG12J101}, author = {Johnson, Austin J and Chris F. Larsen and Murphy, Nathaniel and Anthony A. Arendt and Zirnheld, S Lee} } @article {84, title = {A new inventory of mountain glaciers and ice caps for the Antarctic periphery}, journal = {Annals of Glaciology}, volume = {54}, year = {2013}, pages = {191-199}, doi = {10.3189/2013AoG63A377}, author = {Andrew Bliss and Regine Hock and J. Graham Cogley} } @article {139, title = {A new semi-automatic approach for dividing glacier complexes into individual glaciers}, journal = {Journal of Glaciology}, volume = {59}, year = {2013}, pages = {925-936}, doi = {10.3189/2013JoG12J138}, author = {Kienholz, C. and Regine Hock and Anthony A. Arendt} } @article {131, title = {A nonsmooth Newton multigrid method for a hybrid, shallow model of marine ice sheets}, journal = {Contemporary Mathematics}, volume = {586}, year = {2013}, pages = {197-205}, author = {Guillaume Jouvet and E. Bueler and Carsten Gr{\"a}ser and Kornhuber, Ralf} } @article {207, title = {An open ocean region in Neoproterozoic glaciations would have to be narrow to allow equatorial ice sheets}, journal = {Geophysical Research Letters}, volume = {40}, year = {2013}, pages = {5503{\textendash}5507}, abstract = {A major goal of understanding Neoproterozoic glaciations and determining their effect on the evolution of life and Earth{\textquoteright}s atmosphere is establishing whether and how much open ocean there was during them. Geological evidence tells us that continental ice sheets had to flow into the ocean near the equator during these glaciations. Here we drive the Parallel Ice Sheet Model with output from four simulations of the ECHAM5/Max Planck Institute Ocean Model atmosphere-ocean general circulation model with successively narrower open ocean regions. We find that extensive equatorial ice sheets form on marine margins if sea ice extends to within about 20{\textdegree} latitude of the equator or less (Jormungand-like and hard snowball states), but do not form if there is more open ocean than this. Given uncertainty in topographical reconstruction and ice sheet ablation parameterizations, we perform extensive sensitivity tests to confirm the robustness of our main conclusions.}, keywords = {ice sheet modeling, Neoproterozoic glaciations, snowball Earth}, issn = {1944-8007}, doi = {10.1002/2013GL057582}, url = {http://dx.doi.org/10.1002/2013GL057582}, author = {Rodehacke, Christian B. and Voigt, Aiko and Ziemen, Florian and Abbot, Dorian S.} } @article {165, title = {The propagation of a surge front on Bering Glacier, Alaska, 2001\&$\#$8211;2011}, journal = {Annals of Glaciology}, volume = {54}, year = {2013}, pages = {221-228}, abstract = {Bering Glacier, Alaska, USA, has a \&$\#$8764;20 year surge cycle, with its most recent surge reaching the terminus in 2011. To study this most recent activity a time series of ice velocity maps was produced by applying optical feature-tracking methods to Landsat-7 ETM+ imagery spanning 2001\&$\#$8211;11. The velocity maps show a yearly increase in ice surface velocity associated with the down-glacier movement of a surge front. In 2008/09 the maximum ice surface velocity was 1.5 {\textpm} 0.017 km a\&$\#$8211;1 in the mid-ablation zone, which decreased to 1.2 {\textpm} 0.015 km a\&$\#$8211;1 in 2009/10 in the lower ablation zone, and then increased to nearly 4.4 {\textpm} 0.03 km a\&$\#$8211;1 in summer 2011 when the surge front reached the glacier terminus. The surge front propagated down-glacier as a kinematic wave at an average rate of 4.4 {\textpm} 2.0 km a\&$\#$8211;1 between September 2002 and April 2009, then accelerated to 13.9 {\textpm} 2.0 km a\&$\#$8211;1 as it entered the piedmont lobe between April 2009 and September 2010. The wave seems to have initiated near the confluence of Bering Glacier and Bagley Ice Valley as early as 2001, and the surge was triggered in 2008 further down-glacier in the mid-ablation zone after the wave passed an ice reservoir area.}, doi = {doi:10.3189/2013AoG63A341}, url = {http://www.ingentaconnect.com/content/igsoc/agl/2013/00000054/00000063/art00024}, author = {Turrin, James and Richard R. Forster and Chris F. Larsen and Sauber, Jeanne} } @article {152, title = {Rapid Submarine Melting Driven by Subglacial Discharge, LeConte Glacier, Alaska}, journal = {Geophysical Research Letters}, volume = {40}, year = {2013}, abstract = {We show that subglacial freshwater discharge is the principal process driving high rates of submarine melting at tidewater glaciers. This buoyant discharge draws in warm seawater, entraining it in a turbulent upwelling flow along the submarine face that melts glacier ice. To capture the effects of subglacial discharge on submarine melting, we conducted 4 days of hydrographic transects during late summer 2012 at LeConte Glacier, Alaska. A major rainstorm allowed us to document the influence of large changes in subglacial discharge. We found strong submarine melt fluxes that increased from 9.1 {\textpm} 1.0 to 16.8 {\textpm} 1.3 m d-1 (ice face equivalent frontal ablation) as a result of the rainstorm. With projected continued global warming and increased glacial runoff, our results highlight the direct impact that increases in subglacial discharge will have on tidewater outlet systems. These effects must be considered when modeling glacier response to future warming and increased runoff.}, keywords = {frontal ablation, submarine melting, tidewater glaciers}, issn = {1944-8007}, doi = {10.1002/grl.51011}, url = {http://dx.doi.org/10.1002/grl.51011}, author = {Roman J. Motyka and Dryer, W. P. and Jason M Amundson and Martin Truffer and Mark Fahnestock} } @article {357, title = {Rapid thinning of lake-calving Yakutat Glacier and the collapse of the Yakutat Icefield, southeast Alaska, USA}, journal = {J. Glaciol.}, volume = {59}, year = {2013}, pages = {149{\textendash}161}, issn = {00221430}, doi = {10.3189/2013J0G12J081}, url = {http://www.igsoc.org/journal/59/213/t12J081.html}, author = {Tr{\"u}ssel, Barbara L. and Motyka, Roman J. and Truffer, M. and Larsen, C. F.} } @article {134, title = {Recent air and ground temperature increases at Tarfala Research Station, Sweden}, journal = {Polar Research}, volume = {32}, year = {2013}, abstract = {Long-term data records are essential to detect and understand environmental change, in particular in generally data-sparse high-latitude and high-altitude regions. Here, we analyse a 47-year air temperature record (1965-2011) at Tarfala Research Station (67{\textdegree} 54.7{\textquoteright}N, 18{\textdegree} 36.7{\textquoteright}E, 1135 m a.s.l.) in northern Sweden, and a nearby 11-year record of 100-m-deep ground temperature (2001-11; 1540 m a.s.l.). The air temperature record shows a mean annual air temperature of -3.5{\textpm}0.9{\textdegree}C ({\textpm}1 standard deviation s) and a linear warming trend of {\textpm}0.042{\textdegree}C yr-1. The warming trend shows large month-to-month variations with the largest trend in January followed by October. Also, the number of days with positive mean daily temperatures and positive degree-day sums has increased during the last two decades compared to the previous period. Temperature lapse rates derived from the mean daily Tarfala record and an air temperature record at the borehole site average 4.5{\textdegree}C km-1 and tend to be higher in summer than in winter. Mean summer air temperatures at Tarfala explain 76\% of the variance of the summer glacier mass balance of nearby Storglacia{\textasciidieresis}ren. Consistent with the observed increase in Tarfala{\textquoteright}s air temperature, the ground temperature record shows significant permafrost warming with the largest trend (0.047{\textdegree}C yr-1) found at 20 m depth.Keywords: Air temperature; climate change; permafrost; lapse rate; degree-days; NAO(Published: 15 July 2013)Citation: Polar Research 2013, 32, 19807, http://dx.doi.org/10.3402/polar.v32i0.19807}, keywords = {Air temperature, climate change, degree-days, lapse rate, NAO, permafrost}, issn = {1751-8369}, url = {http://www.polarresearch.net/index.php/polar/article/view/19807}, author = {Ulf Jonsell and Regine Hock and Martial Duguay} } @article {132, title = {A Reconciled Estimate of Glacier Contributions to Sea Level Rise: 2003 to 2009}, journal = {Science}, volume = {340}, year = {2013}, pages = {852-857}, abstract = {Glaciers distinct from the Greenland and Antarctic Ice Sheets are losing large amounts of water to the world{\textquoteright}s oceans. However, estimates of their contribution to sea level rise disagree. We provide a consensus estimate by standardizing existing, and creating new, mass-budget estimates from satellite gravimetry and altimetry and from local glaciological records. In many regions, local measurements are more negative than satellite-based estimates. All regions lost mass during 2003{\textendash}2009, with the largest losses from Arctic Canada, Alaska, coastal Greenland, the southern Andes, and high-mountain Asia, but there was little loss from glaciers in Antarctica. Over this period, the global mass budget was {\textendash}259 {\textpm} 28 gigatons per year, equivalent to the combined loss from both ice sheets and accounting for 29 {\textpm} 13\% of the observed sea level rise.}, doi = {10.1126/science.1234532}, url = {http://www.sciencemag.org/content/340/6134/852.abstract}, author = {Alex S. Gardner and Geir Moholdt and J. Graham Cogley and Bert Wouters and Anthony A. Arendt and Wahr, John and Berthier, Etienne and Regine Hock and W. Tad Pfeffer and Georg Kaser and Ligtenberg, Stefan R. M. and Bolch, Tobias and Martin J. Sharp and Jon Ove Hagen and van den Broeke, Michiel R. and Paul, Frank} } @article {127, title = {Regional and global projections of twenty-first century glacier mass changes in response to climate scenarios from global climate models}, journal = {Climate Dynamics}, year = {2013}, pages = {1-22}, keywords = {Global climate models, Projections of sea level rise, Regional and global glacier mass changes}, issn = {0930-7575}, doi = {10.1007/s00382-013-1719-7}, url = {http://dx.doi.org/10.1007/s00382-013-1719-7}, author = {Valentina Radi{\'c} and Andrew Bliss and Beedlow, A.Cody and Regine Hock and Miles, Evan and J. Graham Cogley} } @article {86, title = {The role of subsurface heat exchange: energy partitioning at Austfonna ice cap, Svalbard, over 2004-2008}, journal = {Annals of Glaciology}, volume = {54}, year = {2013}, pages = {229-240}, doi = {10.3189/2013AoG63A280}, author = {Torbj{\o}rn I. {\O}STBY and Schuler, T.V. and Jon Ove Hagen and Regine Hock and C H Reijmer} } @article {153, title = {On the seasonal freshwater stratification in the proximity of fast-flowing tidewater outlet glaciers in a sub-Arctic sill fjord}, journal = {Journal of Geophysical Research: Oceans}, volume = {118}, year = {2013}, pages = {1382{\textendash}1395}, abstract = {The Greenland Ice Sheet releases large amounts of freshwater into the fjords around Greenland and many fjords are in direct contact with the ice sheet through tidewater outlet glaciers. Here we present the first seasonal hydrographic observations from the inner part of a sub-Arctic fjord, relatively close to and within 4{\textendash}50 km of a fast-flowing tidewater outlet glacier. This region is characterized by a dense glacial and sea ice cover. Freshwater from runoff, subglacial freshwater (SgFW) discharge, glacial, and sea ice melt are observed above 50{\textendash}90 m depth. During summer, SgFW and subsurface glacial melt mixed with ambient water are observed as a layered structure in the temperature profiles below the low-saline summer surface layer (<7 m). During winter, the upper water column is characterized by stepwise halo- and thermoclines formed by mixing between deeper layers and the surface layer influenced by ice melt. The warm (T > 1{\textdegree}C) intermediate water mass is a significant subsurface heat source for ice melt. We analyze the temperature and salinity profiles observed in late summer with a thermodynamic mixing model and determine the total freshwater content in the layer below the summer surface layer to be between 5\% and 11\%. The total freshwater contribution in this layer from melted glacial ice was estimated to be 1{\textendash}2\%, while the corresponding SgFW was estimated to be 3{\textendash}10\%. The winter measurements in the subsurface halocline layer showed a total freshwater content of about 1\% and no significant contribution from SgFW.}, keywords = {fjord, freshwater sources and their distribution, Greenland Ice Sheet, subglacial freshwater fraction model, subsurface heat sources for glacial ice melt, tidewater outlet glaciers}, issn = {2169-9291}, doi = {10.1002/jgrc.20134}, url = {http://dx.doi.org/10.1002/jgrc.20134}, author = {Mortensen, J. and Bendtsen, J. and Roman J. Motyka and Lennert, K. and Martin Truffer and Mark Fahnestock and Rysgaard, S.} } @article {201, title = {Southeast Greenland high accumulation rates derived from firn cores and ground-penetrating radar}, journal = {Annals of Glaciology}, volume = {54}, year = {2013}, pages = {322-332}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84881651457\&partnerID=40\&md5=6aa824682a2fef9009d445649f72c298}, author = {Mi{\`e}ge, C. and Richard R. Forster and Box, J.E. and Evan W. Burgess and McConnell, J.R. and Pasteris, D.R. and Spikes, V.B.} } @article {204, title = {Summer melt regulates winter glacier flow speeds throughout Alaska}, journal = {Geophysical Research Letters}, year = {2013}, abstract = {Predicting how climate change will affect glacier and ice sheet flow speeds remains a large hurdle towards accurate sea level rise forecasting. Increases in surface melt rates are known to accelerate glacier flow in summer, whereas in winter, flow speeds are believed to be relatively invariant. Here we show that wintertime flow speeds on nearly all major glaciers throughout Alaska are not only variable but are inversely related to melt from preceding summers. For each additional meter of summertime melt, we observe an 11\% decrease in wintertime velocity on glaciers of all sizes, geometries, climates and bed types. This dynamic occurs because inter-annual differences in summertime melt affect how much water is retained in the sub-glacial system during winter. The ubiquity of the dynamic indicates it occurs globally on glaciers and ice sheets not frozen to their beds and thus constitutes a new mechanism affecting sea level rise projections.}, keywords = {Alaska, Ice Dynamics, Mountain Glaciers, Offset Tracking, Sub-Glacial Hydrology, Winter}, issn = {1944-8007}, doi = {10.1002/2013GL058228}, url = {http://dx.doi.org/10.1002/2013GL058228}, author = {Evan W. Burgess and Chris F. Larsen and Richard R. Forster} } @article {85, title = {Surface velocity and ice discharge of the ice cap on King George Island, Antarctica}, journal = {Annals of Glaciology}, volume = {54}, year = {2013}, pages = {111-119}, doi = {10.3189/2013AoG63A517}, author = {Batuhan Osamanoglu and M Braun and Regine Hock and Navarro, Francisco} } @article {lee2013underwater, title = {Underwater sound radiated by bubbles released by melting glacier ice}, journal = {The Journal of the Acoustical Society of America}, volume = {134}, number = {5}, year = {2013}, pages = {4172{\textendash}4172}, publisher = {Acoustical Society of America}, author = {Lee, Kevin M and Wilson, Preston S and Pettit, Erin C} } @article {136, title = {Variable penetration depth of interferometric synthetic aperture radar signals on Alaska glaciers: a cold surface layer hypothesis}, journal = {Annals of Glaciology}, volume = {54}, year = {2013}, pages = {218-223}, doi = {10.3189/2013AoG64A114}, author = {Alessio Gusmeroli and Anthony A. Arendt and D K Atwood and B. Kampes and M. Sanford and J. Young} } @article {121, title = {Accelerated contributions of Canada{\textquoteright}s Baffin and Bylot Island glaciers to sea level rise over the past half century}, journal = {The Cryosphere}, volume = {6}, year = {2012}, pages = {1103{\textendash}1125}, doi = {10.5194/tc-6-1103-2012}, author = {Alex S. Gardner and Geir Moholdt and Anthony A. Arendt and Bert Wouters} } @article {mar, title = {Analysis of low-frequency seismic signals generated during a multiple-iceberg calving event at Jakobshavn Isbr{\ae}, Greenland}, journal = {Journal of Geophysical Research}, volume = {117}, year = {2012}, month = {mar}, pages = {1{\textendash}11}, keywords = {calving, glacier, iceberg, seismology}, issn = {0148-0227}, doi = {10.1029/2011JF002132}, url = {http://www.agu.org/pubs/crossref/2012/2011JF002132.shtml}, author = {Walter, F. and Amundson, J. M. and O{\textquoteright}Neel, S. and Truffer, M. and Fahnestock, M.A. and Fricker, H. A.} } @article {zagorodnov2012borehole, title = {Borehole temperatures reveal details of 20th century warming at Bruce Plateau, Antarctic Peninsula}, journal = {The Cryosphere}, volume = {6}, number = {3}, year = {2012}, pages = {675{\textendash}686}, publisher = {Copernicus GmbH}, author = {Zagorodnov, V and Nagornov, O and Scambos, TA and Muto, A and Mosley-Thompson, E and Erin C Pettit and Tyuflin, S} } @article {80, title = {Calving seismicity from iceberg{\textendash}sea surface interactions}, journal = {Journal of Geophysical Research}, volume = {117}, year = {2012}, pages = {F04029}, doi = {10.1029/2012JF002513}, author = {Timothy C. Bartholomaus and Chris F. Larsen and Shad O'Neel and West, M.} } @article {74, title = {Conventional versus reference-surface mass balance}, journal = {Journal of Glaciology}, volume = {58}, year = {2012}, pages = {278{\textendash}286}, doi = {10.3189/2012JoG11J216}, author = {Huss, M. and Regine Hock and Bauder, A. and Funk, M.} } @article {gusmeroli2012crystal, title = {The crystal fabric of ice from full-waveform borehole sonic logging}, journal = {Journal of Geophysical Research: Earth Surface (2003{\textendash}2012)}, volume = {117}, number = {F3}, year = {2012}, publisher = {Wiley Online Library}, author = {Alessio Gusmeroli and Erin C Pettit and Joseph H Kennedy and Ritz, Catherine} } @article {206, title = {A detailed view into the eruption clouds of Santiaguito volcano, Guatemala, using Doppler radar}, journal = {Journal of Geophysical Research: Solid Earth}, volume = {117}, year = {2012}, pages = {n/a{\textendash}n/a}, abstract = {Using Doppler radar technology we are able to show that eruptions at Santiaguito volcano, Guatemala, are comprised of multiple explosive degassing pulses occurring at a frequency of 0.2 to 0.3 Hz. The Doppler radar system was installed about 2.7 km away from the active dome on the top of Santa Maria volcano. During four days of continuous measurement 157 eruptive events were recorded. The Doppler radar data reveals a vertical uplift of the dome surface of about 50 cm immediately prior to a first degassing pulse. Particle velocities range from 10 to 15 m/s (in the line of sight of the radar). In 80\% of the observed eruptions a second degassing pulse emanates from the dome with significantly higher particle velocities (20{\textendash}25 m/s again line of sight) and increased echo power, which implies an increase in mass flux. We carry out numerical experiments of ballistic particle transport and calculate corresponding synthetic radar signals. These calculations show that the observations are consistent with a pulsed release of material from the dome of Santiaguito volcano.}, keywords = {Doppler radar, eruption dynamics, Santiaguito volcano}, issn = {2156-2202}, doi = {10.1029/2011JB008542}, url = {http://dx.doi.org/10.1029/2011JB008542}, author = {Scharff, L. and Ziemen, F. and Hort, M. and Gerst, A. and Johnson, J. B.} } @article {Aschwanden2012, title = {{An enthalpy formulation for glaciers and ice sheets}}, journal = {J. Glaciol.}, volume = {58}, number = {209}, year = {2012}, pages = {441{\textendash}457}, doi = {10.3189/2012JoG11J088}, author = {Andy Aschwanden and E. Bueler and Constantine Khroulev and Blatter, H.} } @article {59, title = {Gravity and uplift rates observed in southeast Alaska and their comparison with GIA model predictions}, journal = {Journal of Geophysical Research}, volume = {117}, year = {2012}, pages = {B01401}, author = {Tatsuru Sato and Miura, S. and Sun, W. and Sugano, T. and Jeffrey T. Freymueller and Chris F. Larsen and Ohta, Y. and Fujimoto, H. and Inazu, D. and Roman J. Motyka} } @article {neff2012ice, title = {Ice-core net snow accumulation and seasonal snow chemistry at a temperate-glacier site: Mount Waddington, southwest British Columbia, Canada}, journal = {Journal of Glaciology}, volume = {58}, number = {212}, year = {2012}, pages = {1165{\textendash}1175}, publisher = {International Glaciological Society}, author = {Neff, Peter D and Steig, Eric J and Clark, Douglas H and McConnell, Joseph R and Pettit, Erin C and Menounos, Brian} } @article {peter2012ice, title = {Ice-core net snow accumulation and seasonal snow chemistry at a temperate-glacier site: Mount Waddington, southwest British Columbia, Canada}, journal = {Journal of Glaciology}, volume = {58}, number = {212}, year = {2012}, pages = {1165}, author = {Peter, D and Steig, Eric J and Clark, Douglas H and McConnell, Joseph R and Erin, C} } @article {pettit2012listening, title = {Listening to Glaciers: Passive Hydroacoustics Near Marine-Terminating Glaciers}, journal = {Oceanography}, volume = {25}, year = {2012}, publisher = {The Oceanography Society (TOS)}, author = {Erin C Pettit and Nystuen, Jeffrey A and O{\textquoteright}Neel, Shad} } @article {11/2011, title = {Mountain Glaciers and ice caps}, number = {xii}, year = {2012}, month = {11/2011}, pages = {538}, institution = {Arctic Monitoring and Assessment Programme (AMAP)}, address = {Oslo, Norway}, isbn = {978-82-7971-071-4}, author = {Martin J. Sharp and M. Ananicheva and Anthony A. Arendt and Jon Ove Hagen and Regine Hock and E. Josberger and R. D. Moore and W. Tad Pfeffer and G. J. Wolken} } @article {360, title = {Observing calving-generated ocean waves with coastal broadband seismometers, Jakobshavn Isbr{\ae}, Greenland}, journal = {Annals Of Glaciology}, volume = {53}, year = {2012}, pages = {79{\textendash}84}, doi = {10.3189/2012/AoG60A200}, author = {Amundson, J. M. and Clinton, John F and Fahnestock, M.A. and Truffer, M. and Motyka, Roman J. and L{\"u}thi, Martin P.} } @article {123, title = {Outlet glacier response to forcing over hourly to interannual timescales, Jakobshavn Isbr{\ae}, Greenland}, journal = {Journal of Glaciology}, volume = {58}, year = {2012}, pages = {1212}, doi = {10.3189/2012JoG12J065}, author = {Podrasky, David and Martin Truffer and Mark Fahnestock and Jason M Amundson and Cassotto, Ryan and Ian Joughin} } @article {dec, title = {Outlet glacier response to forcing over hourly to interannual timescales, Jakobshavn Isbr{\ae}, Greenland}, journal = {J. Glaciol.}, volume = {58}, year = {2012}, month = {dec}, pages = {1212{\textendash}1226}, issn = {00221430}, doi = {10.3189/2012JoG12J065}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=58{\&}issue=212{\&}spage=1212}, author = {Podrasky, David and Truffer, Martin and Fahnestock, Mark and Amundson, Jason M. and Cassotto, Ryan and Joughin, Ian} } @article {pettit2012passive, title = {Passive underwater acoustic evolution of a calving event}, journal = {Annals of Glaciology}, volume = {53}, number = {60}, year = {2012}, pages = {113}, author = {Erin C Pettit} } @article {199, title = {Plate margin deformation and active tectonics along the northern edge of the Yakutat Terrane in the Saint Elias Orogen, Alaska, and Yukon, Canada}, journal = {Geosphere}, volume = {8}, year = {2012}, pages = {1384-1407}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84873486244\&partnerID=40\&md5=6b0147233ff3aeb0e48bf9b253b6c6ec}, author = {Bruhn, R.L. and Sauber, J. and Cotton, M.M. and Pavlis, T.L. and Evan W. Burgess and Ruppert, N. and Richard R. Forster} } @article {77, title = {Reconstruction of basal properties in ice sheets using iterative inverse methods}, journal = {Journal of Glaciology}, volume = {58}, year = {2012}, pages = {795{\textendash}807}, author = {Habermann, M. and Maxwell, D. and Martin Truffer} } @article {Joughin2012, title = {{Seasonal to decadal scale variations in the surface velocity of Jakobshavn Isbrae, Greenland: Observation and model-based analysis}}, journal = {J. Geophys. Res.}, volume = {117}, number = {F2}, year = {2012}, month = {may}, pages = {1{\textendash}20}, keywords = {glacier, glaciology, ice stream}, issn = {0148-0227}, doi = {10.1029/2011JF002110}, url = {http://www.agu.org/pubs/crossref/2012/2011JF002110.shtml}, author = {Joughin, Ian and Smith, B. E. and Howat, I. M. and Floricioiu, Dana and Alley, Richard B. and Truffer, M. and Fahnestock, M.A.} } @article {carmichael2012seismic, title = {Seismic multiplet response triggered by melt at Blood Falls, Taylor Glacier, Antarctica}, journal = {Journal of Geophysical Research: Earth Surface (2003{\textendash}2012)}, volume = {117}, number = {F3}, year = {2012}, author = {Carmichael, Joshua D and Erin C Pettit and Hoffman, Matt and Fountain, Andrew and Hallet, Bernard} } @article {78, title = {Steady, shallow ice sheets as obstacle problems: well-posedness and finite element approximation}, journal = {SIAM Journal on Applied Mathematics}, volume = {72}, year = {2012}, pages = {1292{\textendash}1314}, author = {Guillaume Jouvet and E. Bueler} } @article {79, title = {Surge dynamics on Bering Glacier, Alaska, in 2008{\textendash}2011}, journal = {The Cryosphere Discuss}, volume = {6}, year = {2012}, pages = {1181{\textendash}1204}, doi = {10.5194/tc-6-1251-2012}, author = {Evan W. Burgess and Richard R. Forster and Chris F. Larsen and M Braun} } @article {76, title = {{Using surface velocities to calculate ice thickness and bed topography: a case study at Columbia Glacier, Alaska, USA}}, journal = {Journal of Glaciology}, volume = {58}, year = {2012}, pages = {1151-1164}, doi = {10.3189/2012JoG11J249}, author = {R ~W McNabb and Regine Hock and Shad O'Neel and L ~A Rasmussen and Ahn, Y. and M Braun and H Conway and Herreid, S. and Ian Joughin and W. Tad Pfeffer and B ~E Smith and Martin Truffer} } @article {61, title = {Analysis of seasonal variations in mass balance and meltwater discharge of the tropical Zongo Glacier by application of a distributed energy balance model}, journal = {Journal of Geophysical Research}, volume = {116}, year = {2011}, pages = {D13105}, doi = {10.1029/2010JD015105}, author = {Sicart, JE and Regine Hock and Ribstein, P. and Litt, M. and Ramirez, E.} } @article {73, title = {Assessing the Status of Alaska{\textquoteright}s Glaciers}, journal = {Science}, volume = {332}, year = {2011}, pages = {1044{\textendash}1045}, doi = {10.1126/science.1204400}, author = {Anthony A. Arendt} } @article {63, title = {Climatic mass balance of the ice cap Vestfonna, Svalbard: A spatially distributed assessment using ERA-Interim and MODIS data}, journal = {Journal of Geophysical Research}, volume = {116}, year = {2011}, pages = {F03009}, doi = {10.1029/2010JF001905}, author = {M{\"o}ller, M. and Finkelnburg, R. and M Braun and Regine Hock and Ulf Jonsell and Pohjola, V.A. and Scherer, D. and Schneider, C.} } @article {154, title = {A complex relationship between calving glaciers and climate}, journal = {Eos, Transactions American Geophysical Union}, volume = {92}, year = {2011}, pages = {305{\textendash}306}, abstract = {Many terrestrial glaciers are sensitive indicators of past and present climate change as atmospheric temperature and snowfall modulate glacier volume. However, climate interpretations based on glacier behavior require careful selection of representative glaciers, as was recently pointed out for surging and debris-covered glaciers, whose behavior often defies regional glacier response to climate [Yde and Paasche, 2010]. Tidewater calving glaciers (TWGs){\textemdash}mountain glaciers whose termini reach the sea and are generally grounded on the seafloor{\textemdash}also fall into the category of non-representative glaciers because the regional-scale asynchronous behavior of these glaciers clouds their complex relationship with climate. TWGs span the globe; they can be found both fringing ice sheets and in high-latitude regions of each hemisphere. TWGs are known to exhibit cyclic behavior, characterized by slow advance and rapid, unstable retreat, largely independent of short-term climate forcing. This so-called TWG cycle, first described by Post [1975], provides a solid foundation upon which modern investigations of TWG stability are built. Scientific understanding has developed rapidly as a result of the initial recognition of their asynchronous cyclicity, rendering greater insight into the hierarchy of processes controlling regional behavior. This has improved the descriptions of the strong dynamic feedbacks present during retreat, the role of the ocean in TWG dynamics, and the similarities and differences between TWG and ice sheet outlet glaciers that can often support floating tongues.}, keywords = {climate, glaciers}, issn = {2324-9250}, doi = {10.1029/2011EO370001}, url = {http://dx.doi.org/10.1029/2011EO370001}, author = {Post, Austin and Shad O'Neel and Roman J. Motyka and Streveler, Gregory} } @article {pettit2011crossover, title = {The crossover stress, anisotropy and the ice flow law at Siple Dome, West Antarctica}, journal = {Journal of Glaciology}, volume = {57}, number = {201}, year = {2011}, pages = {39{\textendash}52}, publisher = {International Glaciological Society}, author = {Erin C Pettit and Waddington, Edwin D and Harrison, William D and Thorsteinsson, Throstur and Elsberg, Daniel and Morack, John and Zumberge, Mark A} } @article {70, title = {Existence and stability of steady-state solutions of the shallow-ice-sheet equation by an energy-minimization approach}, journal = {Journal of Glaciology}, volume = {57}, year = {2011}, pages = {345{\textendash}354}, url = {http://www.ingentaconnect.com/content/igsoc/jog/2011/00000057/00000202/art00016}, author = {Guillaume Jouvet and Rappaz, J. and E. Bueler and Blatter, H.} } @article {69, title = {From ice-shelf tributary to tidewater glacier: continued rapid recession, acceleration and thinning of Rohss Glacier following the 1995 collapse of the Prince Gustav Ice Shelf, Antarctic Peninsula}, journal = {Journal of Glaciology}, volume = {57}, year = {2011}, pages = {397{\textendash}406}, doi = {10.3189/002214311796905578}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=57\&issue=203\&spage=397}, author = {Glasser, NF and Scambos, TA and Bohlander, J. and Martin Truffer and Erin C Pettit and Davies, BJ} } @article {64, title = {Glossary of glacier mass balance and related terms}, journal = {IHP-VII Technical Documents in Hydrology}, volume = {86}, year = {2011}, author = {J. Graham Cogley and Regine Hock and L ~A Rasmussen and Anthony A. Arendt and Bauder, A. and Braithwaite, RJ and Jansson, P. and Georg Kaser and M{\"o}ller, M. and Nicholson, L. and others} } @article {198, title = {Greenland Ice Sheet surface mass balance 1870 to 2010 based on Twentieth Century Reanalysis, and links with global climate forcing}, journal = {Journal of Geophysical Research D: Atmospheres}, volume = {116}, year = {2011}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84855336557\&partnerID=40\&md5=9239bc453a5004bd7a1258a2aaa14f07}, author = {Hanna, E. and Huybrechts, P. and Cappelen, J. and Steffen, K. and Bales, R.C. and Evan W. Burgess and McConnell, J.R. and Steffensen, J.P. and Van Den Broeke, M. and Wake, L. and Bigg, G. and Griffiths, M. and Savas, D.} } @article {66, title = {Growth and collapse of the distributed subglacial hydrologic system of Kennicott Glacier, Alaska, USA, and its effects on basal motion}, journal = {Journal of Glaciology}, volume = {57}, year = {2011}, pages = {985{\textendash}1002}, author = {Timothy C. Bartholomaus and Robert S Anderson and Anderson, S.P.} } @article {155, title = {An increase in crevasse extent, West Greenland: Hydrologic implications}, journal = {Geophysical Research Letters}, volume = {38}, year = {2011}, pages = {n/a{\textendash}n/a}, abstract = {We compare high-resolution 1985 and 2009 imagery to assess changes in crevasse extent in the Sermeq Avannarleq ablation zone, West Greenland. The area occupied by crevasses >2 m wide significantly increased (13 {\textpm} 4\%) over the 24-year period. This increase consists of an expansion of existing crevasse fields, and is accompanied by widespread changes in crevasse orientation (up to 45{\textdegree}). We suggest that a combination of ice sheet thinning and steepening are responsible for the increase in crevasse extent. We examine the potential impact of this change on the hydrology of the ice sheet. We provide a first-order demonstration that moulin-type drainage is more efficient in transferring meltwater fluctuations to the subglacial system than crevasse-type drainage. As enhanced basal sliding is associated with meltwater {\textquotedblleft}pulses{\textquotedblright}, an increase in crevasse extent can therefore be expected to result in a net decrease in basal sliding sensitivity. An increase in crevasse extent may also accelerate cryo-hydrologic warming and enhance surface ablation.}, keywords = {crevasses, Greenland, mass balance, velocity}, issn = {1944-8007}, doi = {10.1029/2011GL048491}, url = {http://dx.doi.org/10.1029/2011GL048491}, author = {Colgan, William and Steffen, Konrad and McLamb, W. Scott and Waleed Abdalati and Rajaram, Harihar and Roman J. Motyka and Phillips, Thomas and Robert S Anderson} } @article {68, title = {Karakoram glacier surge dynamics}, journal = {Geophysical Research Letters}, volume = {38}, year = {2011}, pages = {L18504}, doi = {10.1029/2011GL049004}, author = {Quincey, DJ and M Braun and Glasser, NF and Bishop, MP and I M Howat and Luckman, A.} } @article {67, title = {Observed glacial changes on the King George Island ice cap, Antarctica, in the last decade}, journal = {Global and Planetary Change}, volume = {79}, year = {2011}, pages = {99 - 109}, keywords = {climate change}, issn = {0921-8181}, doi = {10.1016/j.gloplacha.2011.06.009}, url = {http://www.sciencedirect.com/science/article/pii/S0921818111001111}, author = {M R{\"u}ckamp and M Braun and S. Suckro and N. Blindow} } @article {72, title = {The Potsdam Parallel Ice Sheet Model (PISM-PIK)-Part 2: Dynamic equilibrium simulation of the Antarctic ice sheet}, journal = {The Cryosphere}, volume = {5}, year = {2011}, pages = {727-740}, doi = {10.5194/tc-5-727-2011}, url = {http://www.the-cryosphere.net/5/727/2011/tc-5-727-2011.html}, author = {Maria A. Martin and Winkelmann, R. and Haseloff, M. and Albrecht, T. and E. Bueler and Constantine Khroulev and Anders Levermann} } @article {71, title = {The Potsdam Parallel Ice Sheet Model (PISM-PIK){\textendash}Part 1: Model description}, journal = {The Cryosphere}, volume = {5}, year = {2011}, pages = {715{\textendash}726}, doi = {10.5194/tc-5-715-2011}, url = {http://www.the-cryosphere.net/5/715/2011/tc-5-715-2011.html}, author = {Winkelmann, R. and Maria A. Martin and Haseloff, M. and Albrecht, T. and E. Bueler and Constantine Khroulev and Anders Levermann} } @article {46, title = {Reevaluation of the viscoelastic and elastic responses to the past and present-day ice changes in Southeast Alaska}, journal = {Tectonophysics}, volume = {511}, year = {2011}, pages = {79{\textendash}88}, doi = {10.1016/j.tecto.2010.05.009}, author = {Tatsuru Sato and Chris F. Larsen and Miura, S. and Ohta, Y. and Fujimoto, H. and Sun, W. and Roman J. Motyka and Jeffrey T. Freymueller} } @article {62, title = {Regionally differentiated contribution of mountain glaciers and ice caps to future sea-level rise}, journal = {Nature Geoscience}, volume = {4}, year = {2011}, pages = {91{\textendash}94}, doi = {10.1038/NGEO1052}, author = {Valentina Radi{\'c} and Regine Hock} } @article {60, title = {Submarine melting of the 1985 Jakobshavn Isbr{\ae} floating tongue and the triggering of the current retreat}, journal = {Journal of Geophysical Research}, volume = {116}, year = {2011}, pages = {F01007}, doi = {10.1029/2009JF001632}, author = {Roman J. Motyka and Martin Truffer and Mark Fahnestock and Mortensen, J. and Rysgaard, S. and I M Howat} } @article {65, title = {Surface mass balance, thinning and iceberg production, Columbia Glacier, Alaska, 19482007}, journal = {Journal of Glaciology}, volume = {57}, year = {2011}, pages = {431{\textendash}440}, author = {L ~A Rasmussen and H Conway and Krimmel, RM and Regine Hock} } @article {50, title = {100-year mass changes in the Swiss Alps linked to the Atlantic Multidecadal Oscillation}, journal = {Geophysical research letters}, volume = {37}, year = {2010}, pages = {L10501}, doi = {10.1029/2010GL042616}, author = {Huss, M. and Regine Hock and Bauder, A. and Funk, M.} } @article {44, title = {Glacier microseismicity}, journal = {Geology}, volume = {38}, year = {2010}, pages = {319-322}, abstract = {We present a framework for interpreting small glacier seismic events based on data collected near the center of Bering Glacier, Alaska, in spring 2007. We find extremely high microseismicity rates (as many as tens of events per minute) occurring largely within a few kilometers of the receivers. A high-frequency class of seismicity is distinguished by dominant frequencies of 20{\textendash}35 Hz and impulsive arrivals. A low-frequency class has dominant frequencies of 6{\textendash}15 Hz, emergent onsets, and longer, more monotonic codas. A bimodal distribution of 160,000 seismic events over two months demonstrates that the classes represent two distinct populations. This is further supported by the presence of hybrid waveforms that contain elements of both event types. The high-low-hybrid paradigm is well established in volcano seismology and is demonstrated by a comparison to earthquakes from Augustine Volcano. We build on these parallels to suggest that fluid-induced resonance is likely responsible for the low-frequency glacier events and that the hybrid glacier events may be caused by the rush of water into newly opening pathways.}, doi = {10.1130/G30606.1}, url = {http://geology.gsapubs.org/content/38/4/319.abstract}, author = {West, M. and Chris F. Larsen and Martin Truffer and Shad O'Neel and LeBlanc, Laura} } @article {45, title = {Gravity measurements in southeastern Alaska reveal negative gravity rate of change caused by glacial isostatic adjustment}, journal = {Journal of Geophysical Research}, volume = {115}, year = {2010}, pages = {B12406}, doi = {10.1029/2009JB007194}, author = {Sun, W. and Miura, S. and Tatsuru Sato and Sugano, T. and Jeffrey T. Freymueller and Kaufman, M. and Chris F. Larsen and Cross, R. and Inazu, D.} } @article {56, title = {Ice m{\'e}lange dynamics and implications for terminus stability, Jakobshavn Isbr{\ae}, Greenland}, journal = {Journal of Geophysical Research}, volume = {115}, year = {2010}, pages = {F01005}, doi = {10.1029/2009JF001405}, author = {Jason M Amundson and Mark Fahnestock and Martin Truffer and Brown, J. and M P L{\"u}thi and Roman J. Motyka} } @article {48, title = {Iceberg calving as a primary source of regional-scale glacier-generated seismicity in the St. Elias Mountains, Alaska}, journal = {Journal of Geophysical Research}, volume = {115}, year = {2010}, pages = {F04034}, doi = {10.1029/2009JF001598}, author = {Shad O'Neel and Chris F. Larsen and Rupert, N. and Hansen, R.} } @article {51, title = {Recent and future warm extreme events and high-mountain slope stability}, journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences}, volume = {368}, year = {2010}, pages = {2435{\textendash}2459}, doi = {10.1098/rsta.2010.0078}, author = {Huggel, C. and Salzmann, N. and Allen, S. and Caplan-Auerbach, J. and L Fischer and Haeberli, W. and Chris F. Larsen and Schneider, D. and Wessels, R.} } @article {47, title = {Regional and global volumes of glaciers derived from statistical upscaling of glacier inventory data}, journal = {Journal of Geophysical Research}, volume = {115}, year = {2010}, pages = {F01010}, doi = {10.1029/2009JF001373}, author = {Valentina Radi{\'c} and Regine Hock} } @article {54, title = {Results from the Ice-Sheet Model Intercomparison ProjectHeinrich Event INtercOmparison (ISMIP HEINO)}, journal = {Journal of Glaciology}, volume = {56}, year = {2010}, pages = {371-383}, abstract = {Results from the Heinrich Event INtercOmparison (HEINO) topic of the Ice-Sheet Model Intercomparison Project (ISMIP) are presented. ISMIP HEINO was designed to explore internal large-scale ice-sheet instabilities in different contemporary ice-sheet models. These instabilities are of interest because they are a possible cause of Heinrich events. A simplified geometry experiment reproduces the main characteristics of the Laurentide ice sheet, including the sedimented region over Hudson Bay and Hudson Strait. The model experiments include a standard run plus seven variations. Nine dynamic/thermodynamic ice-sheet models were investigated; one of these models contains a combination of the shallow-shelf (SSA) and shallow-ice approximation (SIA), while the remaining eight models are of SIA type only. Seven models, including the SIA-SSA model, exhibit oscillatory surges with a period of \&$\#$8764;1000 years for a broad range of parameters, while two models remain in a permanent state of streaming for most parameter settings. In a number of models, the oscillations disappear for high surface temperatures, strong snowfall and small sediment sliding parameters. In turn, low surface temperatures and low snowfall are favourable for the ice-surge cycles. We conclude that further improvement of ice-sheet models is crucial for adequate, robust simulations of cyclic large-scale instabilities.}, doi = {doi:10.3189/002214310792447789}, url = {http://www.ingentaconnect.com/content/igsoc/jog/2010/00000056/00000197/art00001}, author = {Calov, Reinhard and Greve, Ralf and Abe-Ouchi, Ayako and E. Bueler and Huybrechts, Philippe and Jesse V Johnson and Frank Pattyn and David Pollard and Ritz, Catherine and Fuyuki Saito and Tarasov, Lev} } @article {57, title = {Sky longwave radiation on tropical Andean glaciers: parameterization and sensitivity to atmospheric variables}, journal = {Journal of Glaciology}, volume = {56}, year = {2010}, pages = {854{\textendash}860}, author = {Sicart, JE and Regine Hock and Ribstein, P. and Chazarin, J.P.} } @article {197, title = {A spatially calibrated model of annual accumulation rate on the Greenland Ice Sheet (1958-2007)}, journal = {Journal of Geophysical Research F: Earth Surface}, volume = {115}, year = {2010}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-77951082793\&partnerID=40\&md5=a6430b7a7a93a85254e4f44589f3b0f4}, author = {Evan W. Burgess and Richard R. Forster and Box, J.E. and Mosley-Thompson, E. and Bromwich, D.H. and Bales, R.C. and Smith, L.C.} } @article {53, title = {Tectonic block motion and glacial isostatic adjustment in southeast Alaska and adjacent Canada constrained by GPS measurements}, journal = {Journal of Geophysical Research}, volume = {115}, year = {2010}, pages = {B09407}, doi = {10.1029/2009JB007139}, author = {Elliott, J.L. and Chris F. Larsen and Jeffrey T. Freymueller and Roman J. Motyka} } @article {58, title = {A unifying framework for iceberg-calving models}, journal = {Journal of Glaciology}, volume = {56}, year = {2010}, pages = {822{\textendash}830}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=56\&issue=199\&spage=822}, author = {Jason M Amundson and Martin Truffer} } @article {55, title = {Using L-band SAR coherence to delineate glacier extent}, journal = {Canadian Journal of Remote Sensing}, volume = {36}, year = {2010}, pages = {186{\textendash}195}, author = {D K Atwood and Meyer, F. and Anthony A. Arendt} } @article {Gusmeroli2010, title = {{Vertical distribution of water within the polythermal Storglaci{\"a}ren, Sweden}}, journal = {J. Geophys. Res.}, volume = {115}, number = {F4}, year = {2010}, pages = {1{\textendash}14}, issn = {0148-0227}, doi = {10.1029/2009JF001539}, url = {http://www.agu.org/pubs/crossref/2010/2009JF001539.shtml}, author = {Alessio Gusmeroli and Murray, T. and Jansson, P. and Pettersson, R. and Andy Aschwanden and Booth, A. D.} } @article {49, title = {Volume change of Jakobshavn Isbrae, West Greenland:: 198519972007}, journal = {Journal of Glaciology}, volume = {56}, year = {2010}, pages = {635{\textendash}646}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=56\&issue=198\&spage=635}, author = {Roman J. Motyka and Mark Fahnestock and Martin Truffer} } @article {37, title = {Accurate ocean tide modeling in southeast Alaska and large tidal dissipation around Glacier Bay}, journal = {Journal of oceanography}, volume = {65}, year = {2009}, pages = {335{\textendash}347}, author = {Inazu, D. and Tatsuru Sato and Miura, S. and Ohta, Y. and Nakamura, K. and Fujimoto, H. and Chris F. Larsen and Higuchi, T.} } @article {35, title = {Calving icebergs indicate a thick layer of temperate ice at the base of Jakobshavn Isbr{\ae}, Greenland}, journal = {Journal of Glaciology}, volume = {55}, year = {2009}, pages = {563{\textendash}566}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=55\&issue=191\&spage=563}, author = {M P L{\"u}thi and Mark Fahnestock and Martin Truffer} } @article {42, title = {Changes of glaciers and climate in northwestern North America during the late twentieth century}, journal = {Journal of Climate}, volume = {22}, year = {2009}, pages = {4117{\textendash}4134}, author = {Anthony A. Arendt and Walsh, J. and Harrison, W.} } @article {43, title = {Glacier changes in Alaska: can mass-balance models explain GRACE mascon trends?}, journal = {Annals of Glaciology}, volume = {50}, year = {2009}, pages = {148{\textendash}154}, author = {Anthony A. Arendt and Scott B Luthcke and Regine Hock} } @article {38, title = {Implications for the dynamic health of a glacier from comparison of conventional and reference-surface balances}, journal = {Annals of Glaciology}, volume = {50}, year = {2009}, pages = {25{\textendash}30}, author = {Harrison, W. and Cox, LH and Regine Hock and March, RS and Erin C Pettit} } @article {39, title = {Iterative methods for solving a nonlinear boundary inverse problem in glaciology}, journal = {Journal of Inverse and Ill-posed Problems}, volume = {17}, year = {2009}, pages = {239{\textendash}258}, url = {http://www.reference-global.com/doi/abs/10.1515/JIIP.2}, author = {Avdonin, S. and Kozlov, V. and Maxwell, D. and Martin Truffer} } @article {Aschwanden2009, title = {{Mathematical modeling and numerical simulation of polythermal glaciers}}, journal = {J. Geophys. Res.}, volume = {114}, number = {F1}, year = {2009}, pages = {1{\textendash}10}, issn = {0148-0227}, doi = {10.1029/2008JF001028}, url = {http://www.agu.org/pubs/crossref/2009/2008JF001028.shtml}, author = {Andy Aschwanden and Blatter, H.} } @article {40, title = {A method to estimate the ice volume and ice-thickness distribution of alpine glaciers}, journal = {Journal of Glaciology}, volume = {55}, year = {2009}, pages = {422{\textendash}430}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=55\&issue=191\&spage=422}, author = {Farinotti, D. and Huss, M. and Bauder, A. and Funk, M. and Martin Truffer} } @article {36, title = {Mountain glaciers and ice caps around Antarctica make a large sea-level rise contribution}, journal = {Geophysical Research Letters}, volume = {36}, year = {2009}, pages = {L07501}, author = {Regine Hock and de Woul, M. and Valentina Radi{\'c} and Dyurgerov, M.} } @article {41, title = {Shallow shelf approximation as a {\textquotedblleft}sliding law{\textquotedblright} in a thermomechanically coupled ice sheet model}, journal = {Journal of Geophysical Research}, volume = {114}, year = {2009}, pages = {F03008}, author = {E. Bueler and Brown, J.} } @article {33, title = {Terminus dynamics at an advancing glacier: Taku Glacier, Alaska}, journal = {Journal of Glaciology}, volume = {55}, year = {2009}, pages = {1052{\textendash}1060}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=55\&issue=194\&spage=1052}, author = {Martin Truffer and Roman J. Motyka and Hekkers, M. and I M Howat and King, M.A.} } @article {34, title = {Testing longwave radiation parameterizations under clear and overcast skies at Storglaci{\"a}ren, Sweden}, journal = {The Cryosphere}, volume = {3}, year = {2009}, pages = {75{\textendash}84}, author = {Sedlar, J. and Regine Hock} } @article {22, title = {Analysis of scaling methods in deriving future volume evolutions of valley glaciers}, journal = {Journal of Glaciology}, volume = {54}, year = {2008}, pages = {601{\textendash}612}, author = {Valentina Radi{\'c} and Regine Hock and Oerlemans, J.} } @article {Pattyn2008, title = {{Benchmark experiments for higher-order and full Stokes ice sheet models (ISMIP-HOM)}}, journal = {The Cryosphere}, volume = {2}, year = {2008}, pages = {95{\textendash}108}, author = {Frank Pattyn and Perichon, L. and Andy Aschwanden and Breuer, B. and de Smedt, B. and Gagliardini, O. and Gudmundsson, G. H. and Hindmarsh, R. C. A. and Hubbard, A. L. and Jesse V Johnson and Kleiner, T. and Konovalov, Y. and Martin, C. and Payne, A. J. and David Pollard and Stephen F. Price and M R{\"u}ckamp and Fuyuki Saito and Sou{\v c}ek, O. and Sugiyama, S. and Zwinger, T.} } @article {28, title = {Continued evolution of Jakobshavn Isbrae following its rapid speedup}, journal = {J. geophys. Res}, volume = {113}, year = {2008}, pages = {F04006}, url = {http://www.agu.org/pubs/crossref/2008/2008JF001023.shtml}, author = {Ian Joughin and I M Howat and Mark Fahnestock and B ~E Smith and Krabill, W. and Alley, R.B. and Stern, H. and Martin Truffer} } @article {31, title = {Correspondence: Another surge of Variegated Glacier, Alaska, USA, 2003/04}, journal = {Journal of Glaciology}, volume = {54}, year = {2008}, pages = {192-200}, doi = {doi:10.3189/002214308784409134}, url = {http://www.ingentaconnect.com/content/igsoc/jog/2008/00000054/00000184/art00019}, author = {Harrison, W. and Roman J. Motyka and Martin Truffer} } @article {25, title = {Determination of the seasonal mass balance of four Alpine glaciers since 1865}, journal = {J. Geophys. Res}, volume = {113}, year = {2008}, pages = {F01015}, author = {Huss, M. and Bauder, A. and Funk, M. and Regine Hock} } @article {18, title = {Distribution of snow accumulation on the Svartisen ice cap, Norway, assessed by a model of orographic precipitation}, journal = {Hydrological Processes}, volume = {22}, year = {2008}, pages = {3998{\textendash}4008}, author = {Schuler, T.V. and Crochet, P. and Regine Hock and Jackson, M. and Barstad, I. and J{\'o}hannesson, T.} } @article {19, title = {Earth tides observed by gravity and GPS in southeastern Alaska}, journal = {Journal of Geodynamics}, volume = {46}, year = {2008}, pages = {78{\textendash}89}, author = {Tatsuru Sato and Miura, S. and Ohta, Y. and Fujimoto, H. and Sun, W. and Chris F. Larsen and Heavner, M. and Kaufman, AM and Jeffrey T. Freymueller} } @article {32, title = {Glacier, fjord, and seismic response to recent large calving events, Jakobshavn Isbr{\ae}, Greenland}, journal = {Geophysical Research Letters}, volume = {35}, year = {2008}, pages = {L22501}, url = {http://www.agu.org/pubs/crossref/2008/2008GL035281.shtml}, author = {Jason M Amundson and Martin Truffer and M P L{\"u}thi and Mark Fahnestock and West, M. and Roman J. Motyka} } @article {30, title = {Glacier melt, air temperature, and energy balance in different climates: The Bolivian Tropics, the French Alps, and northern Sweden}, journal = {J. Geophys. Res}, volume = {113}, year = {2008}, pages = {D24113}, doi = {10.1029/2008JD010406}, author = {Sicart, JE and Regine Hock and Six, D.} } @article {17, title = {Glacier Recession on Heard Island, Southern Indian Ocean}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {40}, year = {2008}, pages = {199{\textendash}214}, url = {http://www.bioone.org/doi/abs/10.1657/1523-0430(06-084)\%5BTHOST\%5D2.0.CO;2}, author = {Thost, D.E. and Martin Truffer} } @article {Joughin2008a, title = {{Ice-front variation and tidewater behavior on Helheim and Kangerdlugssuaq Glaciers, Greenland}}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {113}, number = {1}, year = {2008}, month = {jan}, pages = {1{\textendash}11}, abstract = {We used satellite images to examine the calving behavior ofHelheim and Kangerdlugssuaq Glaciers, Greenland, from 2001 to 2006, a period in which they retreated and speed up. These data show that many large iceberge-calving episodes coincided with teleseismically detected glacial erthquakes, suggesting that calving-related processes are the source of seismicity. For each of several events for which we hace observations, the ice front calved back to a large, pre-existing rift. These refits form where the ice has thinned to near flotation as the ice front retreats down back side of a bathymetric high, which agrees well with earlier theoretical predictions. In adition to recent retreat in a period of high temperature, analysis of several images shows that Helhaim retreated in the 20th Century during a warmer period and then re-adcanced during a subsequent cooler period. This apparent sensitivity to waming suggests that higher temperatures may promote an initial retread off a bathymetric high that is then sustained by tidewater dynamics as the ice front retreats into depper water. The cycle of frontal advance and retreat in less than a century indicates that tidewater glaciers in Greenland can advance rapidly. Greenland{\textquoteright}s larger resorvoir of inland ice and conditions that favor the formation of ice shelves likely contribute to the rapid rates of advance.}, isbn = {0148-0227}, issn = {21699011}, doi = {10.1029/2007JF000837}, url = {http://www.agu.org/pubs/crossref/2008/2007JF000837.shtml}, author = {Joughin, Ian and Howat, Ian and Alley, Richard B. and Ekstrom, Goran and Fahnestock, Mark and Moon, Twila and Nettles, Meredith and Truffer, Martin and Tsai, Victor C.} } @article {29, title = {Ice-front variation and tidewater behavior on Helheim and Kangerdlugssuaq Glaciers, Greenland}, journal = {Journal of Geophysical Research}, volume = {113}, year = {2008}, pages = {F01004}, url = {http://www.agu.org/pubs/crossref/2008/2007JF000837.shtml}, author = {Ian Joughin and I M Howat and Alley, R.B. and Ekstrom, G. and Mark Fahnestock and Moon, T. and Nettles, M. and Martin Truffer and Tsai, V.C.} } @article {203, title = {Influence of snowpack layering on human-triggered snow slab avalanche release}, journal = {Cold Regions Science and Technology}, volume = {54}, year = {2008}, pages = {176-182}, author = {Habermann, M and Schweizer, J and Jamieson, B} } @article {21, title = {Internal accumulation on Storglaciaren, Sweden, in a multi-layer snow model coupled to a distributed energy-and mass-balance model}, journal = {Journal of Glaciology}, volume = {54}, year = {2008}, pages = {61{\textendash}72}, author = {C H Reijmer and Regine Hock} } @article {24, title = {An iterative scheme for determining glacier velocities and stresses}, journal = {Journal of Glaciology}, volume = {54}, year = {2008}, pages = {888{\textendash}898}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=54\&issue=188\&spage=888}, author = {Maxwell, D. and Martin Truffer and Avdonin, S. and Stuefer, M.} } @article {200, title = {Mass balance of the Greenland ice sheet from 1958 to 2007}, journal = {Geophysical Research Letters}, volume = {35}, year = {2008}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-58249086581\&partnerID=40\&md5=f29d2f8e4a2c1845220d5fc846c65f0a}, author = {Eric Rignot and Box, J.E. and Evan W. Burgess and Hanna, E.} } @article {26, title = {Recent glacier mass changes in the Gulf of Alaska region from GRACE mascon solutions}, journal = {Journal of Glaciology}, volume = {54}, year = {2008}, pages = {767{\textendash}777}, author = {Scott B Luthcke and Anthony A. Arendt and Rowlands, D.D. and J J McCarthy and Chris F. Larsen} } @article {20, title = {Seasonal fluctuations in the advance of a tidewater glacier and potential causes: Hubbard Glacier, Alaska, USA}, journal = {Journal of Glaciology}, volume = {54}, year = {2008}, pages = {401{\textendash}411}, url = {http://openurl.ingenta.com/content/xref?genre=article\&issn=0022-1430\&volume=54\&issue=186\&spage=401}, author = {Ritchie, J.B. and C S Lingle and Roman J. Motyka and Martin Truffer} } @article {27, title = {Seasonality of snow accumulation at Mount Wrangell, Alaska, USA}, journal = {Journal of Glaciology}, volume = {54}, year = {2008}, pages = {273{\textendash}278}, url = {http://www.ingentaconnect.com/content/igsoc/jog/2008/00000054/00000185/art00008}, author = {Kanamori, S. and Benson, C.S. and Martin Truffer and Matoba, S. and Solie, D.J. and Shiraiwa, T.} } @article {11, title = {Climate sensitivity of Storglaciaren, Sweden: an intercomparison of mass-balance models using ERA-40 re-analysis and regional climate model data}, journal = {Annals of glaciology}, volume = {46}, year = {2007}, pages = {342{\textendash}348}, author = {Regine Hock and Valentina Radi{\'c} and de Woul, M.} } @conference {14, title = {Comparison of remote sensing derived glacier facies maps with distributed mass balance modelling at Engabreen, northern Norway.}, booktitle = {Proceedings of a workshop on Andean Glaciology and a symposium on the Contribution from Glaciers and Snow Cover to Runoff from Mountains in Different Climates during the 7th Scientific Assembly of the IAHS, Foz do Iguacu, Brazil, 4-9 April 2005.}, year = {2007}, publisher = {IAHS Press}, organization = {IAHS Press}, author = {M Braun and Schuler, T.V. and Regine Hock and Brown, I. and Jackson, M. and Ginot, P. and Sicart, JE and others} } @conference {10, title = {Deriving glacier mass balance from accumulation area ratio on Storglaci{\"a}ren, Sweden.}, booktitle = {Proceedings of a workshop on Andean Glaciology and a symposium on the Contribution from Glaciers and Snow Cover to Runoff from Mountains in Different Climates during the 7th Scientific Assembly of the IAHS, Foz do Iguacu, Brazil, 4-9 April 2005.}, year = {2007}, publisher = {IAHS Press}, organization = {IAHS Press}, author = {Regine Hock and Kootstra, D.S. and C H Reijmer and Ginot, P. and Sicart, JE and others} } @article {13, title = {Exact solutions to the thermomechanically coupled shallow-ice approximation: effective tools for verification}, journal = {Journal of Glaciology}, volume = {53}, year = {2007}, pages = {499{\textendash}516}, author = {E. Bueler and Brown, J. and C S Lingle} } @article {12, title = {Fast computation of a viscoelastic deformable Earth model for ice-sheet simulations}, journal = {Annals of Glaciology}, volume = {46}, year = {2007}, pages = {97{\textendash}105}, author = {E. Bueler and C S Lingle and Brown, J.} } @article {15, title = {Flotation and retreat of a lake-calving terminus, Mendenhall Glacier, southeast Alaska, USA}, journal = {Journal of Glaciology}, volume = {53}, year = {2007}, pages = {211{\textendash}224}, author = {Boyce, E.S. and Roman J. Motyka and Martin Truffer} } @article {7, title = {Glacier changes in southeast Alaska and northwest British Columbia and contribution to sea level rise}, journal = {J. Geophys. Res}, volume = {112}, year = {2007}, pages = {F01007}, author = {Chris F. Larsen and Roman J. Motyka and Anthony A. Arendt and Echelmeyer, K.A. and Geissler, P.E.} } @article {9, title = {Glacier-dammed lake outburst events of Gornersee, Switzerland}, journal = {Journal of Glaciology}, volume = {53}, year = {2007}, pages = {189{\textendash}200}, author = {Huss, M. and Bauder, A. and Werder, M. and Funk, M. and Regine Hock} } @article {16, title = {Glaciervolcano interactions in the North Crater of Mt Wrangell, Alaska}, journal = {Annals of Glaciology}, volume = {45}, year = {2007}, pages = {48{\textendash}57}, author = {Benson, C.S. and Roman J. Motyka and McNUTT, S. and M P L{\"u}thi and Martin Truffer} } @article {5, title = {Hubbard Glacier, Alaska: 2002 closure and outburst of Russell Fjord and postflood conditions at Gilbert Point}, journal = {Journal of geophysical research}, volume = {112}, year = {2007}, pages = {F02004}, author = {Roman J. Motyka and Martin Truffer} } @article {8, title = {Meteorological observations and energy balance at Storglaci{\"a}ren, northern Sweden}, journal = {IAH Publ}, volume = {318}, year = {2007}, pages = {186-194}, author = {Konya, K. and Regine Hock and Naruse, R.} } @article {tremblay2007ocean, title = {Ocean acoustic effects of explosions on land: Evaluation of Cook Inlet beluga whale habitability}, journal = {The Journal of the Acoustical Society of America}, volume = {122}, number = {5}, year = {2007}, pages = {3002{\textendash}3002}, publisher = {Acoustical Society of America}, author = {Tremblay, Sara K and Anderson, Thomas S and Pettit, Erin C and Scheifele, Peter M and Potty, Gopu R and Miller, James H} } @article {6, title = {Post Little Ice Age Glacial Rebound in Glacier Bay National Park and Surrounding Areas}, journal = {Alaska Park Science}, volume = {6}, year = {2007}, pages = {36{\textendash}41}, author = {Roman J. Motyka and Chris F. Larsen and Jeffrey T. Freymueller and Echelmeyer, K.A.} } @article {3, title = {Rethinking ice sheet time scales}, journal = {Science}, volume = {315}, year = {2007}, pages = {1508{\textendash}1510}, doi = {10.1126/science.11404}, author = {Martin Truffer and Mark Fahnestock} } @article {pettit2007role, title = {The role of crystal fabric in flow near an ice divide}, journal = {Journal of Glaciology}, volume = {53}, number = {181}, year = {2007}, pages = {277{\textendash}288}, publisher = {International Glaciological Society}, author = {Erin C Pettit and Thorsteinsson, Throstur and Jacobson, H Paul and Waddington, Edwin D} } @article {4, title = {Volumearea scaling vs flowline modelling in glacier volume projections}, journal = {Annals of Glaciology}, volume = {46}, year = {2007}, pages = {234{\textendash}240}, author = {Valentina Radi{\'c} and Regine Hock and Oerlemans, J.} } @article {364, title = {Episodic reactivation of large-scale push moraines in front of the advancing Taku Glacier, Alaska}, journal = {J. Geophys. Res.}, volume = {111}, year = {2006}, pages = {{\textendash}01009}, issn = {0148-0227}, doi = {10.1029/2005JF000385}, url = {http://www.agu.org/pubs/crossref/2006/2005JF000385.shtml}, author = {Kuriger, Elsbeth Maria and Truffer, M. and Motyka, Roman J. and Bucki, Adam K.} } @article {pettit2006ice, title = {Ice Flow at Low Deviatoric Stress: Siple Dome, West Antarctica}, journal = {Glacier Science and Environmental Change}, year = {2006}, pages = {300{\textendash}303}, publisher = {Wiley Online Library}, author = {Erin C Pettit} } @article {mar, title = {In situ measurements of till deformation and water pressure}, journal = {J. Glaciol.}, volume = {52}, year = {2006}, month = {mar}, pages = {175{\textendash}182}, issn = {00221430}, doi = {10.3189/172756506781828700}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=52{\&}issue=177{\&}spage=175}, author = {Truffer, M. and Harrison, W.D.} } @article {dec, title = {Rapid erosion of soft sediments by tidewater glacier advance: Taku Glacier, Alaska, USA}, journal = {Geophys. Res. Lett.}, volume = {33}, year = {2006}, month = {dec}, pages = {1{\textendash}5}, issn = {0094-8276}, doi = {10.1029/2006GL028467}, url = {http://www.agu.org/pubs/crossref/2006/2006GL028467.shtml}, author = {Motyka, Roman J. and Truffer, M. and Kuriger, Elsbeth Maria and Bucki, Adam K.} } @article {362, title = {Time-dependent basal stress conditions beneath Black Rapids Glacier, Alaska, USA, inferred from measurements of ice deformation and surface motion}, journal = {J. Glaciol.}, volume = {52}, year = {2006}, pages = {347{\textendash}357}, issn = {00221430}, doi = {10.3189/172756506781828593}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=52{\&}issue=178{\&}spage=347}, author = {Amundson, J. M. and Truffer, M. and L{\"u}thi, Martin P.} } @article {conway2005candidate, title = {Candidate drill site near the Ross-Amundsen ice divide, West Antarctica}, journal = {DRAFT, Mar}, year = {2005}, author = {Conway, H and Neumann, TA and Stephen F. Price and Waddington, ED and Morse, D and Taylor, K and Mayewski, PA and Dixon, D and Erin C Pettit and Steig, EJ} } @article {174, title = {Exact solutions and numerical verification for isothermal ice sheets}, journal = {J. Glaciol.}, volume = {51}, year = {2005}, pages = {291{\textendash}306}, doi = {10.3189/172756505781829449}, url = {http://www.ingentaconnect.com/content/igsoc/jog/2005/00000051/00000173/art00011}, author = {E. Bueler and C. S. Lingle and J. A. Kallen-Brown and D. N. Covey and L. N. Bowman} } @article {Aschwanden2005, title = {{Meltwater production due to strain heating in Storglaci{\"a}ren, Sweden}}, journal = {J. Geophys. Res.}, volume = {110}, number = {F4}, year = {2005}, keywords = {glacier, polythermal, strain heating}, issn = {0148-0227}, doi = {10.1029/2005JF000328}, url = {http://www.agu.org/pubs/crossref/2005/2005JF000328.shtml}, author = {Andy Aschwanden and Blatter, H.} } @article {conway2005proposed, title = {Proposed drill site near the Ross{\textendash}Amundsen ice divide, West Antarctica}, journal = {White Paper for the US Ice Core Working Group}, year = {2005}, author = {Conway, H and Neumann, TA and Stephen F. Price and Waddington, ED and Morse, D and Taylor, K and Mayewski, PA and Dixon, D and Erin C Pettit and Steig, EJ} } @article {sep, title = {Record negative glacier balances and low velocities during the 2004 heatwave in Alaska, USA: implications for the interpretation of observations by Zwally and others in Greenland}, journal = {Journal of Glaciology}, volume = {51}, year = {2005}, month = {sep}, pages = {663{\textendash}664}, issn = {0022-1430}, doi = {10.3189/172756505781829016}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=51{\&}issue=175{\&}spage=663 https://www.cambridge.org/core/product/identifier/S002214300021085X/type/journal{\_}article}, author = {Truffer, Martin and Harrison, W.D. and March, R.S.} } @article {mar, title = {The basal speed of valley glaciers: an inverse approach}, journal = {J. Glaciol.}, volume = {50}, year = {2004}, month = {mar}, pages = {236{\textendash}242}, issn = {00221430}, doi = {10.3189/172756504781830088}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=50{\&}issue=169{\&}spage=236}, author = {Truffer, M.} } @article {elsberg2004depth, title = {Depth-and time-dependent vertical strain rates at Siple Dome, Antarctica}, journal = {Journal of Glaciology}, volume = {50}, number = {171}, year = {2004}, pages = {511{\textendash}521}, publisher = {International Glaciological Society}, author = {Elsberg, Daniel H and Harrison, William D and Zumberge, Mark A and Morack, John L and Erin C Pettit and Waddington, Edward D and Husmann, Eric} } @article {Joughin2004b, title = {{Large fluctuations in speed on Greenland{\textquoteright}s Jakobshavn Isbrae glacier.}}, journal = {Nature}, volume = {432}, number = {7017}, year = {2004}, month = {dec}, pages = {608{\textendash}610}, abstract = {It is important to understand recent changes in the velocity of Greenland glaciers because the mass balance of the Greenland Ice Sheet is partly determined by the flow rates of these outlets. Jakobshavn Isbrae is Greenland{\textquoteright}s largest outlet glacier, draining about 6.5 per cent of the ice-sheet area, and it has been surveyed repeatedly since 1991 (ref. 2). Here we use remote sensing data to measure the velocity of Jakobshavn Isbrae between 1992 and 2003. We detect large variability of the velocity over time, including a slowing down from 6,700 m yr(-1) in 1985 to 5,700 m yr(-1) in 1992, and a subsequent speeding up to 9,400 m yr(-1) by 2000 and 12,600 m yr(-1) in 2003. These changes are consistent with earlier evidence for thickening of the glacier in the early 1990s and rapid thinning thereafter. Our observations indicate that fast-flowing glaciers can significantly alter ice discharge at sub-decadal timescales, with at least a potential to respond rapidly to a changing climate.}, isbn = {0028-0836}, issn = {0028-0836}, doi = {10.1038/nature03130}, author = {Joughin, Ian and Abdalati, Waleed and Fahnestock, Mark} } @article {366, title = {Probing the till beneath Black Rapids Glacier, Alaska, USA}, journal = {J. Glaciol.}, volume = {50}, year = {2004}, pages = {608{\textendash}614}, issn = {00221430}, doi = {10.3189/172756504781829693}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=50{\&}issue=171{\&}spage=608}, author = {Harrison, W.D. and Truffer, M. and Echelmeyer, K. A. and Pomraning, D. A. and Abnett, K. A. and Ruhkick, R. H.} } @article {pettit2003effects, title = {Effects of basal sliding on isochrones and flow near an ice divide}, journal = {Annals of Glaciology}, volume = {37}, number = {1}, year = {2003}, pages = {370{\textendash}376}, publisher = {International Glaciological Society}, author = {Erin C Pettit and Jacobson, H Paul and Waddington, Edwin D} } @article {pettit2003ice, title = {Ice flow at low deviatoric stress}, journal = {Journal of Glaciology}, volume = {49}, number = {166}, year = {2003}, pages = {359{\textendash}369}, publisher = {International Glaciological Society}, author = {Erin C Pettit and Waddington, Edwin D} } @article {370, title = {Of isbr{\ae} and ice streams}, journal = {Ann. Glaciol.}, volume = {36}, year = {2003}, pages = {66{\textendash}72}, issn = {02603055}, doi = {10.3189/172756403781816347}, author = {Truffer, M. and Echelmeyer, K. A.} } @article {kay2003spatial, title = {Spatial relationships between snow contaminant content, grain size, and surface temperature from multispectral images of Mt. Rainier, Washington (USA)}, journal = {Remote sensing of environment}, volume = {86}, number = {2}, year = {2003}, pages = {216{\textendash}231}, publisher = {Elsevier}, author = {Kay, Jennifer E and Gillespie, Alan R and Hansen, Gary B and Erin C Pettit} } @article {jan, title = {A surface motion survey of Black Rapids Glacier, Alaska, U.S.A.}, journal = {Ann. Glaciol.}, volume = {36}, year = {2003}, month = {jan}, pages = {29{\textendash}36}, issn = {02603055}, doi = {10.3189/172756403781816095}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0260-3055{\&}volume=36{\&}issue=1{\&}spage=29}, author = {Fatland, Dennis R. and Lingle, Craig S. and Truffer, M.} } @article {pettit2003unique, title = {Unique dynamic behaviors of ice divides: Siple Dome and the rheological properties of ice}, journal = {PhD Dissertation}, year = {2003}, author = {Erin C Pettit} } @article {zumberge2002measurement, title = {Measurement of vertical strain and velocity at Siple Dome, Antarctica, with optical sensors}, journal = {Journal of Glaciology}, volume = {48}, number = {161}, year = {2002}, pages = {217{\textendash}225}, publisher = {International Glaciological Society}, author = {Zumberge, Mark A and Elsberg, Daniel H and Harrison, William D and Husmann, Eric and Morack, John L and Erin C Pettit and Waddington, Edwin D} } @article {369, title = {Mechanisms of fast flow in Jakobshavns Isbr{\ae}, Greenland, Part III: Measurements of ice deformation, temperature and cross-borehole conductivity in boreholes to the bedrock}, journal = {J. Glaciol.}, volume = {48}, year = {2002}, pages = {369{\textendash}385}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=48{\&}issue=162{\&}spage=369}, author = {L{\"u}thi, Martin P. and Funk, M. and Iken, A. and Truffer, M. and Gogineni, S.} } @article {Fahnestock2001a, title = {{High geothermal heat flow, Basal melt, and the origin of rapid ice flow in central Greenland.}}, journal = {Science (New York, N.Y.)}, volume = {294}, number = {5550}, year = {2001}, month = {dec}, pages = {2338{\textendash}42}, abstract = {Age-depth relations from internal layering reveal a large region of rapid basal melting in Greenland. Melt is localized at the onset of rapid ice flow in the large ice stream that drains north off the summit dome and other areas in the northeast quadrant of the ice sheet. Locally, high melt rates indicate geothermal fluxes 15 to 30 times continental background. The southern limit of melt coincides with magnetic anomalies and topography that suggest a volcanic origin.}, issn = {0036-8075}, doi = {10.1126/science.1065370}, url = {http://www.ncbi.nlm.nih.gov/pubmed/11743197}, author = {Fahnestock, M and Abdalati, W and Joughin, Ian and Brozena, J and Gogineni, P} } @article {feb, title = {Implications of till deformation on glacier dynamics}, journal = {J. Glaciol.}, volume = {47}, year = {2001}, month = {feb}, pages = {123{\textendash}134}, issn = {00221430}, doi = {10.3189/172756501781832449}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=47{\&}issue=156{\&}spage=123}, author = {Truffer, M. and Echelmeyer, K. A. and Harrison, W.D.} } @article {sep, title = {Glacier motion dominated by processes deep in underlying till}, journal = {J. Glaciol.}, volume = {46}, year = {2000}, month = {sep}, pages = {213{\textendash}221}, issn = {00221430}, doi = {10.3189/172756500781832909}, url = {http://openurl.ingenta.com/content/xref?genre=article{\&}issn=0022-1430{\&}volume=46{\&}issue=153{\&}spage=213}, author = {Truffer, M. and Harrison, W.D. and Echelmeyer, K. A.} } @article {oh1999analysis, title = {Analysis of spectroscopic properties of erbium doped Ta 2 O 5{\textendash}Al 2 O 3{\textendash}SiO 2 optical fiber}, journal = {Journal of non-crystalline solids}, volume = {259}, number = {1}, year = {1999}, pages = {10{\textendash}15}, publisher = {North-Holland}, author = {Oh, Kyunghwan and Pettit, Erin and Kilian, A and Morse, TF} } @article {oh1999analysis, title = {Analysis of spectroscopic properties of erbium doped Ta 2 O 5{\textendash}Al 2 O 3{\textendash}SiO 2 optical fiber}, journal = {Journal of non-crystalline solids}, volume = {259}, number = {1}, year = {1999}, pages = {10{\textendash}15}, publisher = {North-Holland}, author = {Oh, Kyunghwan Pettit, Erin and Kilian, A and Morse, TF} } @article {oh1999analysis, title = {Analysis of spectroscopic properties of erbium doped Ta 2 O 5{\textendash}Al 2 O 3{\textendash}SiO 2 optical fiber}, journal = {Journal of non-crystalline solids}, volume = {259}, number = {1}, year = {1999}, pages = {10{\textendash}15}, publisher = {North-Holland}, author = {Oh, Kyunghwan and Kilian, A and Morse, TF} } @article {oh1999analysis, title = {Analysis of spectroscopic properties of erbium doped Ta< sub> 2 O< sub> 5{\textendash}Al< sub> 2 O< sub> 3{\textendash}SiO< sub> 2 optical fiber}, journal = {Journal of non-crystalline solids}, volume = {259}, number = {1}, year = {1999}, pages = {10{\textendash}15}, publisher = {Elsevier}, author = {Oh, Kyunghwan and Kilian, A and Morse, TF} } @article {373, title = {Subglacial drilling at Black Rapids Glacier, Alaska, U.S.A : drilling method and sample descriptions}, journal = {J. Glaciol.}, volume = {45}, year = {1999}, pages = {495{\textendash}505}, author = {Truffer, M. and Motyka, Roman J. and Harrison, W.D. and Echelmeyer, K. A. and Fisk, B. and Tulaczyk, S.} } @article {oh1999thermal, title = {Thermal effects on the excited state absorption and upconversion process of erbium ions in germanosilicate optical fiber}, journal = {Journal of non-crystalline solids}, volume = {259}, number = {1}, year = {1999}, pages = {51{\textendash}56}, publisher = {Elsevier}, author = {Pettit, Erin and Simpson, Jay and Oh, Kyunghwan and Morse, TF} } @article {oh1999thermal, title = {Thermal effects on the excited state absorption and upconversion process of erbium ions in germanosilicate optical fiber}, journal = {Journal of non-crystalline solids}, volume = {259}, number = {1}, year = {1999}, pages = {51{\textendash}56}, publisher = {Elsevier}, author = {Oh, Kyunghwan and Morse, TF} } @article {375, title = {The sliding velocity over a sinusoidal bed at high water pressure}, journal = {Journal of Glaciology}, volume = {44}, year = {1998}, pages = {379{\textendash}382}, doi = {10.3189/S0022143000002707}, author = {Truffer, Martin and Iken, Almut} } @article {anderson1997effects, title = {The effects of APU characteristics on the design of hybrid control strategies for hybrid electric vehicles}, journal = {PROGRESS IN TECHNOLOGY}, volume = {58}, year = {1997}, pages = {305{\textendash}311}, publisher = {SAE INTERNATIONAL}, author = {Anderson, Catherine and Erin C Pettit} } @article {374, title = {The relationship between subglacial water pressure and velocity of Findelengletscher, Switzerland, during its advance and retreat} volume = {43}, journal = {Journal of Glaciology}, year = {1997}, pages = {328{\textendash}338}, abstract = {Findelengletscher, Switzerland, advanced about 250 m between 1979$\backslash$nand 1985, and retreated thereafter. Subglacial water pressure, surface$\backslash$nvelocity and surface strain rate were determined at several sites.$\backslash$nThe measurements were made early in the melt seasons of 1980, 1982,$\backslash$n1985 and 1994 and in the autumn of 1983 and the winter of 1984. Changes$\backslash$nof surface geometry were assessed from aerial photographs. The estimated$\backslash$nbasal shear stress changed little between 1982 and 1994. Nevertheless,$\backslash$nlarge changes in the relationship of subglacial water pressure and$\backslash$nsurface velocity were observed, which cannot be reconciled with the$\backslash$nmost commonly used sliding law unless it is modified substantially$\backslash$nConsideration of possible reasons indicates that a change in the$\backslash$nsubglacial drainage system occurred, probably involving a change$\backslash$nin the degree of cavity interconnection. Isolated cavities damp the$\backslash$nvariations in sliding velocity that normally result from changes$\backslash$nin water pressure, because the pressure in isolated cavities decreases$\backslash$nas the sliding speed increases. In contrast, by transmitting water-pressure$\backslash$nfluctuations to a larger area of the bed, interconnected cavities$\backslash$namplify the effect of water-pressure fluctuations on sliding speed.$\backslash$nThus, we suggest that an observed decrease in velocity (for a given$\backslash$nwater pressure) between 1982 and 1994 was a consequence of a decrease$\backslash$nin the interconnectedness of the subglacial cavity system.}, isbn = {0022-1430}, issn = {00221430}, doi = {10.1017/CBO9781107415324.004}, author = {Iken, A. and Truffer, M.} } @article {Kamb1994a, title = {{Mechanical and hydrologic basis for the rapid motion of a large tidewater glacier: 2. Interpretation}}, journal = {Journal of Geophysical Research}, volume = {99}, number = {B8}, year = {1994}, pages = {15231}, issn = {0148-0227}, doi = {10.1029/94JB00467}, url = {http://www.agu.org/pubs/crossref/1994/94JB00467.shtml http://doi.wiley.com/10.1029/94JB00467}, author = {Kamb, Barclay and Engelhardt, Hermann and Fahnestock, Mark A. and Humphrey, Neil and Meier, Mark and Stone, Dan} } @article {241, title = {Assessing streamflow sensitivity to variations in glacier mass balance}, volume = {123}, pages = {329-341}, issn = {0165-0009, 1573-1480}, doi = {10.1007/s10584-013-1042-7}, url = {http://link.springer.com/10.1007/s10584-013-1042-7}, author = {O{\textquoteright}Neel, Shad and Hood, Eran and Arendt, Anthony and Sass, Louis} } @article {383, title = {Glaciers and Climate of the Upper Susitna Basin, Alaska}, author = {Bliss, Andrew and Hock, Regine and Wolken, Gabriel and Whorton, Erin and Aubry-Wake, Caroline and Braun, Juliana and Gusmeroli, Alessio and Harrison, Will and Hoffman, Andrew and Liljedahl, Anna and others} } @article {156, title = {Hazard assessment of the Tidal Inlet landslide and potential subsequent tsunami, Glacier Bay National Park, Alaska}, journal = {Landslides}, volume = {4}, pages = {205-215}, abstract = {An unstable rock slump, estimated at 5 to 10\&$\#$8201;{\texttimes}\&$\#$8201;106 m3, lies perched above the northern shore of Tidal Inlet in Glacier Bay National Park, Alaska. This landslide mass has the potential to rapidly move into Tidal Inlet and generate large, long-period-impulse tsunami waves. Field and photographic examination revealed that the landslide moved between 1892 and 1919 after the retreat of the Little Ice Age glaciers from Tidal Inlet in 1890. Global positioning system measurements over a 2-year period show that the perched mass is presently moving at 3\&$\#$8211;4 cm annually indicating the landslide remains unstable. Numerical simulations of landslide-generated waves suggest that in the western arm of Glacier Bay, wave amplitudes would be greatest near the mouth of Tidal Inlet and slightly decrease with water depth according to Green\&$\#$8217;s law. As a function of time, wave amplitude would be greatest within approximately 40 min of the landslide entering water, with significant wave activity continuing for potentially several hours.}, doi = {doi:10.1007/s10346-007-0084-1}, url = {http://www.ingentaconnect.com/content/klu/10346/2007/00000004/00000003/00000084}, author = {Wieczorek, Gerald and Geist, Eric and Roman J. Motyka and Jakob, Matthias} } @article {157, title = {Hubbard Glacier update: another closure of Russell Fiord in the making?}, journal = {Journal of Glaciology}, volume = {54}, pages = {562-564}, doi = {doi:10.3189/002214308785837066}, url = {http://www.ingentaconnect.com/content/igsoc/jog/2008/00000054/00000186/art00020}, author = {Roman J. Motyka and Lawson, Daniel and Finnegan, David and Kalli, George and Molnia, Bruce and Anthony A. Arendt} }