Greenland Ice Loss Driven by Warming Seas. AFP, February 14, 2010. "Greenland's continent-sized icesheet is being significantly eroded by winds and currents that drive warmer water into fjords, where it carves out the base of coastal glaciers, according to studies [PDF, 7 pp] released on February 14. The icy mass sitting atop Greenland holds enough water to boost global sea levels by seven metres (23 feet), potentially drowning low-lying coastal cities and deltas around the world. At present, the ocean watermark is rising at around three millimetres (0.12 inches) per year, a figure that compares with 1.8mm (0.07 inches) annually in the early 1960s. But Greenland's contribution has more than doubled in the past decade, and scientists suspect climate change is largely to blame, although exactly how this is occurring is fiercely debated.
"Some theories point to air temperatures, which are rising faster in far northern latitudes than the global average. A rival idea is that shifting currents and subtropical ocean waters moving north are eroding the foundation of coastal glaciers, accelerating their slide into the sea, especially those inside Greenland's many fjords. Until now, however, these studies have been mainly based on mathematical models rather than observation. A team of scientists led by Fiammetta Straneo of Woods Hole Oceanographic Institution in Massachusetts set out to help fill that data void. Working off of a ship in July and September 2008, the researchers took detailed measurements of the water properties in the Sermilik Fjord connecting Helheim Glacier in eastern Greenland with the ocean. They found deep water streaming into the fjord was 3.0-4.0 degrees Celsius (37.4-39.2 degrees Fahrenheit), warm enough to cut into the base of the glaciers and hasten their plunge into the sea."
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