Changes in ice front position on Greenland's outlet glaciers from 1992 to 2007

[1] Previous studies in Greenland show that retreat of tidewater glaciers may be linked to recent increases in ice loss, raising Greenland's contribution to sea level rise. We examined ice front changes of 203 tidewater glaciers, land-terminating glaciers, and glaciers terminating with ice shelves to understand Greenland glacier behavior over three periods: 1992–2000, 2000–2006, and 2006–2007. We observed synchronous, ice sheet–wide increases in tidewater retreat during 2000–2006 relative to 1992–2000, coinciding with a 1.1°C increase in mean summer temperature at coastal weather stations. Rates of retreat for the southeast and east slowed during 2006–2007 when temperatures were slightly cooler than the 2000–2006 average. Our work suggests that regional Greenland tidewater retreat responds strongly to climate change, with higher temperatures corresponding to increasing retreat, and helps confirm a link between ice thickness, velocity, and ice front position.

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