Glaciers & Ice Caps To Dominate Sea-Level Rise Through 21st Century

| Thu Jul. 19, 2007 5:16 PM EDT

Ice loss from glaciers and ice caps is expected to cause more global sea rise this century than the massive Greenland and Antarctic ice sheets. A startling new University of Colorado at Boulder study finds glaciers and ice caps currently contributing 60 percent of the world's ice to the oceans, with the rate markedly accelerating in the past decade. The contribution is presently 100 cubic miles of ice annually, a volume nearly equal to the water in Lake Erie, and is rising by three cubic miles per year. In contrast, Greenland now contributes 28 percent of the total global sea rise from ice loss and Antarctica 12 percent. The acceleration of glaciers and ice caps is due, at least in part, to rapid changes in the flow of tidewater glaciers discharging icebergs into the ocean. The team estimates the accelerating melt of glaciers and ice caps could add 4 inches to 9.5 inches of additional sea-level rise globally by 2100 &mdash not including the thermal expansion of warming ocean water, which could double those numbers. A one-foot sea-level rise typically causes a shoreline retreat of 100 feet or more. . . In other words, even if the big canons stay frozen, these little guys are going to inflict a lot of damage.

This of the Jakobshavn Glacier in Greenland. JULIA WHITTY

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