Melting Trend of Greenland’s Glaciers Not Necessarily Steady and Linear
16.02.2007 - Other
A year ago, a study in the journal Science revealed that discharge from Greenland's glaciers had doubled between 2000 and 2005, but these results were based on "snapshots" of discharge taken five years apart. A new study shows that glaciers' behaviour can change a lot from year to year and that future trends cannot necessarily be predicted from short records of recent changes.
This new study measured the speed, geometry and discharge of two Greenland glaciers' between 2000 and 2006. Kangerdlugssuaq and Helheim are "outlet" glaciers : their front edges reach all the way to the sea.
At Kangerdlugssuaq, roughly 80 percent of the total increase in discharge occurred in less than one year in 2005, followed by a 25 percent drop the following years. At Helheim, discharge increased between 2000 and 2003, and then by an even greater amount between 2004 and 2005. It then dropped in 2006 to its near 2000 value.
Glaciers lost ice as their front edges began calving, became lighter and floated off the bottom, which led to more ice breaking off as the ice was buoyed up by water. The fronts stabilized once the ice had retreated to shallower parts of the fjords and again rested on the bottom.
