Figure 1. The 100 square-mile ice island that broke off the Petermann Glacier heads out of the Petermann Fjord in this image taken by NASA's Aqua satellite on August 21, 2010. Image credit: NASA. I've constructed a 7-frame satellite animation available here that shows the calving and break-up of the Petermann Glacier ice island. The animation begins on August 5, 2010, and ends on September 21, with images spaced about 8 days apart. The images were taken by NASA's Aqua and Terra satellites.
"No humans were present on the morning of August 4, 2010, in a remote fjord in Northwest Greenland, when the air vibrated with a thunderous crack as one of the largest icebergs in world history calved from the Petermann Glacier, the island's second largest ocean-terminating glacier. Where the glacier meets the sea, a 43 mile-long tongue of floating ice existed at the beginning of 2010. On August 4 2010, a quarter of this 43 mile-long tongue of floating ice fractured off, spawning a 100 square mile ice island four times the size of Manhattan, with a thickness half that of the Empire State building. According to Andreas Muenchow, associate professor of physical ocean science and engineering at the University of Delaware's College of Earth, Ocean, and Environment, the freshwater stored in this ice island could have kept the Delaware or Hudson rivers flowing for more than two years, or kept all U.S. public tap water flowing for 120 days. There was speculation that the ice island could find its way into the open Atlantic Ocean in two years, and potentially pose a threat to oil platforms and ships. However, as the ice island made its turn to get from the narrow Petermann Fjord to enter Nares Strait between Greenland and Canada, the mighty iceberg split into thousands of small icebergs that will not pose an unusual threat to shipping when they emerge into the Atlantic. [....]
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PS: A recomendação para ler o resto da nota referenciada é muito forte. Por exemplo, vejam este outro extracto: "According to an article in livescience.com, "Driftwood and narwhal remains found along the Ellesmere coast have radiocarbon dates from roughly 3,000 to 6,800 years ago, implying that the ice has been intact since those remains were deposited." All of the these calving events are evidence that the ice sheets in the Arctic are responding as one would expect to significantly warmer temperatures."
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