Greenland’s enormous ice sheet is melting at such an accelerated rate that it may have reached a “tipping point,” and could become a major factor in sea-level rise around the world within two decades, scientists said in a study published on Monday. The Arctic is warming at twice the average rate of the rest of the planet, and the new research adds to the evidence that the ice loss in Greenland, which lies mainly above the Arctic Circle, is speeding up as the warming increases. The authors found that ice loss in 2012, more than 400 billion tons per year, was nearly four times the rate in 2003. After a lull in 2013-14, losses have resumed. The study is the latest in a series of papers published this month suggesting that scientific estimates of the effects of a warming planet have been, if anything, too conservative. Just a week ago, a separate study of ice loss in Antarctica found that the continent is contributing more to rising sea levels than previously thought. Another new analysis suggested that the oceans are warming far faster than earlier estimates. Warming oceans are currently the leading cause of sea-level rise, since water expands as it warms.
New York Times 21st Jan 2019 read more »
Greenland is melting faster than scientists previously thought, with the pace of ice loss increasing four-fold since 2003, new research has found. Enormous glaciers in Greenland are depositing ever larger chunks of ice into the Atlantic ocean, where it melts. But scientists have found that the largest ice loss in the decade from 2003 actually occurred in the southwest region of the island, which is largely glacier-free. This suggests surface ice is simply melting as global temperatures rise, causing gushing rivers of meltwater to flow into the ocean and push up sea levels. South-west Greenland, not previously thought of as a source of woe for coastal cities, is set to “become a major future contributor to sea level rise,” the research states. “We knew we had one big problem with increasing rates of ice discharge by some large outlet glaciers,” said Michael Bevis, lead author of the paper and a professor of geodynamics at Ohio State University. “But now we recognize a second serious problem: increasingly, large amounts of ice mass are going to leave as meltwater, as rivers that flow into the sea.” The research provides fresh evidence of the dangers posed to vulnerable coastal places as diverse as Miami, Shanghai, Bangladesh and various Pacific islands as climate change shrinks the world’s land-based ice.
Guardian 21st Jan 2019 read more »
Independent 21st Jan 2019 read more »