A new study from the National Center for Atmospheric Research (NCAR) has found that Greenland's melting ice may have a greater effect on sea level rise on the northeastern coasts of the U.S. and Canada than previously hypothesized.
"If Greenland's ice melts at moderate to high rates, ocean circulation by 2100 may shift and cause sea levels off the northeast coast of North America to rise by about 12 to 20 inches (about 30 to 50 centimeters) more than in other coastal areas. The research builds on recent reports that have found that sea level rise associated with global warming could adversely affect North America, and its findings suggest that the situation is more threatening than previously believed," NCAR said in its preliminary report.
The group of researchers on the project, which was led by NCAR's Aixue Hu, included scientists from NCAR, the University of Colorado at Boulder, and Florida State University. The report research was funded by the U.S. Department of Energy and the National Science Foundation.
Greenland ice has been melting at a rate of about 7 percent per year within the last few years. But Hu and his group modeled several different scenarios based on different melting rates using NCAR's Community Climate System Model, which simulates global climate change. They did not include overall global sea level rise by other factors such as Arctic ice melt, but sea level rise based on Greenland ice melt alone.
The group wants to educate the public on the misconception that the oceans of the world spread out evenly.
"The oceans will not rise uniformly as the world warms. Ocean dynamics will push water in certain directions, so some locations will experience sea level rise that is larger than the global average," NCAR scientist Gerald Meehl, co-author of the paper, said in a statement.
If Greenland's ice melt rate slows to 1 percent per year, northeastern sea levels would, at most, rise 8 inches (20 cm) by 2100.
If Greenland's ice melt rate slows to 3 percent per year, it could raise world sea level by 21 inches (54 cm) by 2100.
Most interesting may be the group's predictions in the unlikely event that Greenland's ice melt rate were to continue its 7 percent increase per year.
In that scenario, the increased drain of freshwater into the North Atlantic would change oceanic circulation of warm water pumping into the Arctic, which would in turn lead to a temporary recovery of Arctic sea ice.
A full report of NCAR's findings will be published in the journal Geophysical Research Letters this Friday.