@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 {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} }