A study appearing in Science magazine today shows a vast ice sheet in northeast Greenland has begun a phase of speeded-up ice loss, contributing to destabilization that will cause global sea-level rise for “decades to come.”
A team of scientists, including a researcher from the University of Kansas-based Center for Remote Sensing of Ice Sheets (CReSIS), found that since 2012 warmer air and sea temperatures have caused the Zachariæ Isstrøm ice sheet to “retreat rapidly along a downward-sloping, marine-based bed.”
By itself, the Zachariæ Isstrøm glacier holds enough water to trigger a half-meter rise in ocean levels around the world.
“The downward slope combined with warming ocean temperatures is what seems to be causing the acceleration now and why we predict it will continue to accelerate over the next few decades,” Paden said. “Until its grounding line is pinned on an upslope bed, then the dynamic effect is expected to decrease.”
A neighboring glacier with an equal amount of ice, named Nioghalvfjersfjorden, is also melting fast but receding gradually along an uphill bed, according to the researchers. Because Zachariæ Isstrøm is on a downslope, it’s disappearing faster.
Together, the ice in Zachariæ Isstrøm and Nioghalvfjersfjorden represent a 1.1-meter rise in sea levels worldwide. According to the KU researcher, the team’s work is intended to inform people in coastal areas who need to make choices about the future.
“From a societal standpoint, the reason why there’s so much focus on ice sheets is because predicted sea level rise will affect nearly every coastal country — the United States for sure, and low-lying countries with limited resources are likely to be the worst off. Mass displacements of potentially millions of people will affect countries that have no coastlines. We study this to have an understanding of how soon things are likely to happen and to help us use our limited resources to help mitigate the problem.”
Source: Office of Public Affairs, University of Kansas News – Contact: Brendan M. Lynch