Earth Sciences136
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A Rough Start
The magnitude 6.0 earthquake that struck Malawi on Saturday night, December 19, spurred us into action. We had been closely following the earthquakes there, but this one confirmed the unusual nature of the seismic sequence. It also happened to be the most destructive. Leonard Kalindekafe, director of Malawi’s Geological Survey, asked us to come and…
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A Quiet Crackling Below the Ice
As a child, I believed that I could hear the ocean in a seashell. Now when I think about the sounds of the sea, I imagine the roar of waves crashing on the beach. But from the vantage point of a ship with noisy engines, the water seems silent. In 1490, Leonardo da Vinci observed,…
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Ready to Sail
Today we arrived at McMurdo, an American research station that hosts Antarctica’s largest community—about 1,000 people during austral summer. To get here, a US Air Force cargo plane picked us up in Christchurch, New Zealand, and landed us on the ice nearby. Today is a balmy summer day of 30°F, not much colder than the…
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Temporary Seismic Networks Can Help Developing Nations Pinpoint Quakes
Earthquakes can be devastating, as Haiti has shown. They can trigger tsunamis, like the one in Indonesia in 2004, and create enough ground shaking to topple buildings. Aftershocks can prevent people from returning to their homes for weeks, even months. The immediate response to a natural disaster is to search for those lost, treat the…
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Continental Breakup in East Africa
Africa is ripping apart along a 4,000 kilometer seam called the East Africa Rift, which stretches from the Red Sea to Mozambique. This huge continental tear started in the north about 25 million years ago and has been gradually unzipping to the south, with rifting in Malawi starting about 10 million years ago. Breaking up…
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Scientists Respond to Earthquakes in Malawi
In December, nearly a dozen earthquakes of magnitude 5 or greater rattled the southeast African nation of Malawi, killing four, injuring hundreds, and making thousands homeless. The region had been calm for decades, so the earthquakes caught everyone by surprise. But aftershocks continue, and more quakes can be expected. Seismologists from Columbia University’s Lamont-Doherty Earth…
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Melting Glaciers–Tracking Their Path
I am a geophysicist at Columbia’s Lamont-Doherty Earth Observatory, and I study how different processes shape the bottom of oceans and rivers. One focus of my research is the continental shelves off Antarctica, especially in the Bellingshausen and Amundsen Sea, and the role of ice sheets in their formation. I made my first trip to…
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Scientists Drill Deepest Hole off New Zealand
Layers of sand tell of fluctuations in climate, sea level
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What’s Making West Antarctica Melt?
The view from the Palmer is so blindingly white today that the eye cannot tell where the ice ends and the clouds begin. In this unusually icy Antarctic summer, it seems strange to contemplate melting ice. But glaciers, here and in Greenland, are melting faster than they are growing. We know that ice sheets have…
