"Surface melting could become the dominant process then," Vieli said, due to warming air temperatures, which can't break up the ice as quickly. The glacier's frozen bed may also become wet and lubricated, which could hasten sliding somewhat, but not to the same extent as calving in the fjord. "The retreat can continue up the deep bed, but probably not much beyond," Richard Alley of Pennsylvania State University said. "After that, surface melting and surface melting thawing the bed to speed sliding are probably the two big issues, and neither is likely to be a run-for-the-hill-fast issue." Glaciers' recession onto land could temper Greenland's contribution to sea level rise. But both Alley and Vieli noted that the situation is much different in the ice sheets of Antarctica. There, the continent's massive ice streams stay below sea level for hundreds of miles, so as they retreat, there will be no escaping the warming ocean's corrosive influence. Related Links: HowStuffWorks.com: Global Warming How Stuff Works: If the polar caps melted, how much would it contribute to sea level rise? |
advertisement
Put Discovery News on Your Site!
|
-
our sites
-
video
mobile
-
shop
-
stay connected
-
corporate
