Earth Sciences136
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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…
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Tundra, Microbes and World Climate
O. Roger Anderson is a microbiologist at Lamont-Doherty Earth Observatory who studies bacteria, amoebas, fungi and other microorganisms. Lately he has been thinking about how tiny organisms that inhabit the vast northern tundra regions could contribute to changing climate, since, like humans, they breathe in oxygen and breathe out carbon dioxide. Recently, Anderson found a…
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Rebuilding Haiti: The 10-Year Plan
The horrors of Haiti’s earthquake continue to unfold. The quake itself killed perhaps 100,000 people. The inability to organize rapid relief is killing tens of thousands more. More than 1 million people are exposed to hunger and disease and, with the rain and hurricane seasons approaching, are vulnerable to further hazards. Even an economy as…
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Haiti: Physics of Quakes Past, and Future
The earthquake that struck Haiti took place along what is called a strike-slip fault—a place where tectonic plates on each side of a fault line are moving horizontally in opposite directions, like hands rubbing together. When these plates lock together, stress builds; eventually they slip; and this produces shaking. This quake was fairly shallow; it…
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Rough seas bring unexpected rewards
Working in Antarctica is always a challenge but this trip has had more than the usual setbacks. After working feverishly in Punta Arenas to prepare our ship, we had to wait two days for some essential cargo to arrive. Not long after pushing off, we encountered rough weather in the Drake Passage, a region notorious…
