A huge ice island is floating free in Arctic waters after splitting from the Petermann Glacier in northwest Greenland. University of Delaware researcher Andreas Muenchow announced the calving took place in the early morning of August 5 and amounts to the largest ice chunk lost in the Arctic since 1962. It measures 100 square miles and 625 feet thick. The National Ice Center provides a satellite image and map here.
According to Muenchow, the island is “four times the size of Manhattan,” and equated to 25 percent of the formerly 43-mile long Petermann Glacier. Its thickness is about half the height of the Empire State Building. “The freshwater stored in this ice island could keep the Delaware or Hudson rivers flowing for more than two years,” explained Muenchow. “It could also keep all U.S. public tap water flowing for 120 days.”
His associate, Trudy Wohllenben of the Canadian Ice Service, first discovered the island. Her organization identifies this as the third major calving event from Petermann Glacier since 2001. Wohllenben and Muenchow are two of a team of scientists working with the National Science Foundation (NSF) to conduct research in Nares Strait between Greenland and Canada.
These scientists believe the new ice island will enter Nares Strait and either block it or break up and lodge between real islands in the Strait. Such was the fate of a 230-square-mile ice chunk which calved from the Ward Hunt Ice Shelf in Canada in 1962. Another possibility is that the pieces could travel south toward the Atlantic over the course of the next two years and melt in warmer waters. Right now, the island is floating about 620 miles south of the North Pole.
Neither Muenchow nor Wohllenben identified the cause of this calving event, but media sources are quick to blame global warming. The Sydney Morning Herald cites the ice island as the latest climate-change tragedy in a long list of weather related catastrophes. It quoted Peter McGuire, managing director at CWA Global Markets, saying “Mother Nature is playing a very evil hand. It’s always the poor that suffer.”
CNN reports, “Environmentalists say ice melt is being caused by global warming with Arctic temperature in the 1990s reaching their warmest level of any decade in at least 2,000 years.” However, the Science and Public Policy Institute (SPPI) published an April 2009 study revealing a downward trend in Arctic temperatures since the 1940s. It quoted 2008 NASA research attributing Arctic ice melt to “unusual northbound currents and winds” bringing warm water toward the north and blowing sea ice southward.
Moreover, calving is not the same as melting. Calving happens when a section of ice breaks off a glacier, iceberg, or ice shelf, which may have nothing to do with melting. Obama’s chief science advisor, John Holdren, described calving caused by too much ice in a 1971 essay warning of the dangers of a coming ice age: “Even more dramatic results are possible, however; for instance, a sudden outward slumping of the Antarctic ice cap, induced by added weight, could generate a tidal wave of proportions unprecedented in recorded history.” Admittedly, such an outlandish prediction does undermine Holdren’s credibility, but it is true that calving is just as likely to be caused by buildup of ice as by melting. In the case of the Petermann Glacier, it is more likely because the Greenland ice sheet increased by two inches per year from 1993 through 2003, and “radar stations in northern Greenland are rapidly being surrounded by the growing ice sheet,” reports SPPI.
The CNN story goes on to lament, “Current trends could see the Arctic Ocean become ice free in summer months within decades, researchers predict.” The implication is an ice-free summer would forebode doom, yet CNN is pulling a bait-and-switch. Sea ice is not the same as glaciers, icebergs, and ice shelves, all of which originate on land. Sea ice is simply frozen ocean water. And scientists agree cyclical changes in sea ice are common. The University of Illinois’ chart of global sea ice extent in the past 30 years shows practically no trend whatsoever, with 2008 and 2009 peak sea-ice seasons equivalent to the 1979-2000 mean.
So even though the Petermann Glacier calving can hardly be classified as a threat to the environment or a portent of impending disaster, depend upon major media to warn otherwise. Just remember, Greenland didn’t get its name by being covered with ice as it is today. And as SPPI noted, “the Greenland ice sheet was entirely absent 850,000 years ago: therefore, even if Greenland’s ice were to melt, its disappearance would be entirely within the natural variability of the climate.”
