This is an archive of AGU's GeoSpace blog through 1 July 2020. New content about AGU research can be found on Eos and the AGU newsroom.

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14 November 2011

Behind the scenes at the Smithsonian

AGU’s hometown of Washington, DC, recently played host to Digital Capital Week, a week-long festival focused on bringing together designers, entrepreneurs, and social innovators of all kinds. As part of DC Week, the Smithsonian Institution offered the chance to go behind the scenes at the National Museum of Natural History for their first-ever tweetup, #SITweetup. A tweetup is when Twitter users meet face-to-face to discuss shared interests. For the #SITweetup, ten lucky people from a variety of professions were chosen randomly for a tour of the Paleobiology Department — and I was one of them!


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21 December 2010

A (really really) Old Farmer’s Almanac: A record of specific weather patterns 55 million years ago

San Francisco will be rainy through this week, but I am learning about weather 55 million years ago, as recorded in the rings of ancient trees found in a coal seam on Ellesmere Island, above the Arctic Circle.

The trees caught the interest of University of Hawaii geologists Hope Jahren and Brian Schubert and their collaborators. “The wood is of spectacular preservation,“ Jahren said during her Thursday afternoon talk given in session B44B. “This is mummified wood”–wood that somehow avoided petrification.


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17 December 2010

Abrupt climate change: New data from lakes

Abrupt climate change is a provocative topic. How fast does it happen? How does it shift so quickly? What are the effects of climate swings on life?

It turns out that scientists are still teasing apart the details of if and when abrupt climate change happens. In yesterday’s Emiliani Lecture, session PP41C, David Hodell from the University of Cambridge presented his analysis of lake sediment samples and what they tell us about abrupt climate change during the last ice age, about 10,000-20,000 years ago.


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13 December 2010

Why did northeast Africa become dry 2 million years ago?

What led to the expansion of grasslands in northeast Africa around 2 million years ago? In PP12B-07 “Why did Africa became dry in the mid-Pliocene?,” Peter deMenocal of Columbia University’s Lamont-Doherty Earth Observatory presented a new hypothesis suggesting that the emergence of changes in sea surface temperature in the Pacific and Indian oceans resulted in a decrease in precipitation in northeast Africa.


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