Shrinking glaciers and a collapsing ice shelf
There was a bunch of gloomy news on the global warming front over the past couple of weeks,
Glaciers retreating at a rapid rate
starting with a United Nations report that claims many of the world’s glaciers are retreating at a rapid rate. UN scientists claim that the glaciers they studied are retreating at a rate that is between five and ten times faster than they were a decade earlier. Since glaciers provide water to millions of people, particularly in India and North America, their decline is of obvious significance.
Wilkins Ice Shelf collapses in Antarctica
A 405 square kilometer chunk of the Wilkins Ice Shelf in Antarctica collapsed in early March and fell into the ocean:
From: National Snow and Ice Data Centre
Satellite images indicate that the Wilkins began its collapse on February 28; data revealed that a large iceberg, 41 by 2.5 kilometers (25.5 by 1.5 miles), fell away from the ice shelf’s southwestern front, triggering a runaway disintegration of 405 square kilometers (160 square miles) of the shelf interior (Figure 1). The edge of the shelf crumbled into the sky-blue pattern of exposed deep glacial ice that has become characteristic of climate-induced ice shelf break-ups such as the Larsen B in 2002. A narrow beam of intact ice, just 6 kilometers wide (3.7 miles) was protecting the remaining shelf from further breakup as of March 23 (Figure 2).
Scientists track ice shelves and study collapses carefully because some of them hold back glaciers, which if unleashed, can accelerate and raise sea level. Scambos said, “The Wilkins disintegration won’t raise sea level because it already floats in the ocean, and few glaciers flow into it. However, the collapse underscores that the Wilkins region has experienced an intense melt season. Regional sea ice has all but vanished, leaving the ice shelf exposed to the action of waves.”
With Antarctica’s summer melt season drawing to a close, scientists do not expect the Wilkins to further disintegrate in the next several months. “This unusual show is over for this season,” Scambos said. “But come January, we’ll be watching to see if the Wilkins continues to fall apart.”
Check out the time lapse animation showing the extent of the collapse from the NSIDC website.
