By Laurel Morales
http://stream.publicbroadcasting.net/production/mp3/knau/local-knau-889185.mp3
Flagstaff, AZ – New research shows melting glaciers are contributing much less than originally thought to rising sea levels. Northern Arizona University geographer Erik Schiefer and a team of researchers have recalculated the glacier melt in Alaska. Arizona Public Radio's Laurel Morales spoke with him and has this report.
Erik Schiefer and four other researchers published their recalculations in a paper in the February issue of Nature Geoscience. They found that the rate of glacier melt is about one third lower than previous estimates.
SCHIEFER: We are able to measure rates of glacier melt for about of the glaciers in Alaska where as previous studies only looked at a few of the thousands of glaciers.
He and the team of researchers used satellite imagery that spans vast areas to calculate glacier melt. He says that allowed them to get a much more accurate estimate.
SCHIEFER: In the previous most comprehensive assessment was based on flying aircraft over the center lines of a selected subset of glaciers and measuring the elevation of the glacier. Since they only measured the center lines that ended up underestimating the glacier melt overall because the sides of the glaciers are behaving differently than the center lines.
But Schiefer says they are not questioning the acceleration of the rate of glacier melt which is still a worry for ongoing sea level rise. He says the substantial increase of glacier melt since the 1990s is now pushing up the rise in sea level more than double the average rate for the last 40 years.
Schiefer plans to extend his research to other glaciers in the Antarctic and Greenland. The researchers were most interested in the mountain glaciers in Alaska because they are most sensitive to climate change.
For Arizona Public Radio I'm Laurel Morales in Flagstaff.