Two of Greenland’s largest glaciers have lost even more ice to global warming over the last month.
A huge chunk of the Petermann Glacier measuring 29 square kilometers (11 square miles) — roughly half the size of Manhattan — broke away. The Petermann, in northern Greenland, has lost a major mass of ice — 86 square kilometers (33 square miles) — between 2000 and 2001.
To add insult to injury, an enormous crack further back from the margin of the Petermann Glacier might signal an imminent and bigger breakup.
“If the Petermann Glacier breaks up back to the upstream rift, the loss would be as much as 60 square miles (160 square kilometers),” or one-third of the massive ice field, said Jason Box, a professor of geography at Ohio State University.
The scientists also said that the margin of the massive Jakobshavn glacier has retreated inland further than at any time in the past 150 years of observation. It has has not retreated so far inland “in at least the last 4,000 to 6,000 years,” according to proxies. Jakobshavn’s northern branch has broken up in the last several weeks and the glacier has lost at least 10 square kilometers (three square miles) since the end of the last melt season.
About one-tenth of Greenland’s icebergs come from Jakobshavn, making it the island’s most “productive” glacier. The glacier lost 94 square kilometers (36 square miles) of ice field betwen 2001 and 2005, an event that drew international attention to the impact of global warming on glaciers.
Meanwhile, the roof of an ice tunnel in Argentina’s gigantic Perito Morena glacier, 60 meters high and weighing thousands of tonnes, suddenly collapsed. This event has never occurred before in the middle of the. Scientists blamed global warming for the collapse as well.