EARTH: Antarctic trees surprise scientists

"Warm" and "Antarctica" are not commonly used in the same sentence; however, for scientists, "warm" is a relative term. A team of researchers has discovered that, contrary to previous thinking, the Antarctic continent has experienced periods of warmth since the onset of its most recent glaciation.

Lodged in ocean sediment nearly 20 million years old, ancient pollen and leaf wax samples taken from the Ross Ice Shelf suggest that two brief warming spells, each of which lasted less than 30,000 years, punctuated the omnipresent cold of Antarctica. Warm, again, is a relative term, as the suggested maximum temperature reached a balmy 7 degrees Celsius in the summer—about 11 degrees warmer than conditions today. These data, researchers say, may hold the key to answering how Earth's climate and hydrological systems are inextricably linked. Find out how by reading the story online at http://www.earthmagazine.org/article/antarctic-trees-surprise-scientists.

Make sure to check out all the other great stories in the September issue of EARTH Magazine online at http://www.earthmagazine.org. Find out how physicists fingerprint plutonium; learn how dams and groundwater pumping may influence sea level; and discover how ordinary people are becoming citizen scientists, all in this month's issue of EARTH.

Provided by American Geological Institute