@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 {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 {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 {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 {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 {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 {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} }