Landmark Study of Glacier Paradigms Confirms Global Warming

August 11, 2009 07:00 AM
by Shannon Firth
New research shows that “benchmark glaciers” are melting more rapidly than in the past, jeopardizing marine and other animal life as well as fresh water supplies. Past studies triggered concerns that glacier activity could aggravate border disputes in areas of political instability.

Understanding the Glaciers’ Retreat

The South Cascade Glacier in Washington state, and the Wolverine Glacier and Gulkana Glacier in Alaska, have undergone “rapid and sustained” retreats, noted McClatchy, citing a report from the U.S. Geological Survey released last Thursday.

“Because the three glaciers are in different climates and elevations, they can be used to help understand thousands of other North American glaciers,” explain McClatchy writers Les Blumenthal and Erika Bolstad. The Wolverine Glacier is found on Alaska’s Kenai Peninsula, whereas the Gulkana Glacier is located in the state’s interior.

All three glaciers have shrunk and thinned … with the mass loss rapidly accelerating over the past 15 years,” Thomas Schueneman, a writer for The Web site Global Warming Is Real, noted. The South Cascade Glacier is now only a quarter of the size it was at the turn of the century, reported United Press International.

“We’ve crossed a threshold, and these glaciers along with those globally are shrinking,” Ed Josberger, a USGS scientist in Tacoma, Wash., told McClatchy.

As glaciers diminish they produce less runoff, causing water temperature changes that impact insects, sea life and other animal populations, reported McClatchy. Smaller glaciers also mean less drinking water. The disappearance of Bolivia’s Chacaltaya Glacier this year caused concern over a potential crisis situation for South America’s water supply.

In May, Italy and Switzerland redrew their borders after alpine glaciers grew smaller, reported findingDulcinea. What’s significant about this, explained Than Hansen of Global Warming is Real, is that “large scale ice and glacier melt” could “trigger widespread conflict” in areas were border disputes might not be settled as agreeably, such as Kashmir, the Indian-Chinese border area and the Northwest Passage.

Reference: How do scientists study glaciers?

A fact sheet from the USGS, canvassing the recent report, explains that in addition to “repeat photography,” scientists use a “network of stakes” spread across each glacier to gauge “mass balance.” The term “mass balance” is defined as the difference between “ablation,” which is snow that becomes runoff, part of an iceberg wall or water vapor, and accumulation, which is snow that remains as snow. In areas where ablation exceeds accumulation there is a “negative mass balance,” meaning the glacier has shrunk.

NEXT: NASA Launches Rubber Ducks to Research Glacier Interior >

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