Author: Frank O Nitsche2
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Following the Trail of Ancient Icebergs
A few days ago we reached our main study area in the eastern Amundsen Sea. Here we are using sonar to map the contours of the seafloor in great detail. During the last glaciation the Antarctic ice sheet was much larger and covered most of the continental shelf, an underwater extension of the continent that…
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So Much Depends on Sea Ice
Where we work and how we get there depends on the sea ice. The Oden is a powerful icebreaker but it is often faster and more fuel-efficient to go around heavy sea ice then to chop our way through. If the sea ice is several feet thick, we often choose to detour. We actually consult…
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Is Ocean Water Helping to Melt Glaciers?
After crossing the Ross Sea, we’ve reached our first study area: the “Little America Trough.” The oceanographers on board want to find out if warmer water from the deep ocean is rising onto the continental shelf and reaching the ice, making it melt faster. They measure temperature and salinity as well as the water currents.…
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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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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…