No sign of increased snowfall in Antarctica

http://www.nature.com/news/2006/060807/full/060807-14.html

Southern Hemisphere warming has surprisingly not led to increased snowfall over Antarctica during the past 50 years, researchers report today. If the findings are confirmed, this suggests that global sea-level rise might proceed faster than previously thought.

Average surface temperatures in the Southern Hemisphere have increased by roughly 0.5 °C since the 1950s. Climate models predict that the warming and increased evaporation should result in more snowfall over Antarctica, because the warmer air transported southwards would carry more moisture.

But a reconstruction of the Antarctic precipitation record suggests that, at least in the past, this has not been the case.

Weather observations near the poles are scarce and often unreliable, which makes it difficult to determine past precipitation. Andrew Monaghan, a meteorologist at Ohio State University's Byrd Polar Research Center, and his team used a combination of ice-core and model data to fill the large voids between the few stations. The new results double the length of the snowfall record available for Antarctica.

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it seems by this time -- that rubberband effect that precedes an iceage would be seen -- i wonder what the deal is?

what's holding back the snow?

Study says Antarctic snowfall still scarce, but not for long

http://pressherald.mainetoday.com/news/state/060812snowfall.shtml

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The lack of significant change in snowfall is not unexpected and shows that climate change has yet to affect interior Antarctica, Mayewski said. But all other signs indicate it's only a matter of time before the climate warms and causes increased snowfall accumulation, he said.

Beginning in 1979, scientists noticed ice retreating in coastal Antarctic glaciers, he said. More recently, they've observed warming and the collapse of floating ice areas in the Antarctic Peninsula, to the north.

Further research shows that marine air masses are traveling farther inland over Antarctica and that the high-level atmosphere is warming.

"This all suggests that Antarctica may be setting up for significant climate change, and models suggest it could experience the greatest changes on the planet," Mayewski said.

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Insignificant Change in Antarctic Snowfall Since the International Geophysical Year

Andrew J. Monaghan,1* David H. Bromwich,1 Ryan L. Fogt,1 Sheng-Hung Wang,1 Paul A. Mayewski,3 Daniel A. Dixon,3 Alexey Ekaykin,4 Massimo Frezzotti,5 Ian Goodwin,6 Elisabeth Isaksson,7 Susan D. Kaspari,3 Vin I. Morgan,8 Hans Oerter,9 Tas D. Van Ommen,8 Cornelius J. Van der Veen,2 Jiahong Wen10

Antarctic snowfall exhibits substantial variability over a range of time scales, with consequent impacts on global sea level and the mass balance of the ice sheets. To assess how snowfall has affected the thickness of the ice sheets in Antarctica and to provide an extended perspective, we derived a 50-year time series of snowfall accumulation over the continent by combining model simulations and observations primarily from ice cores. There has been no statistically significant change in snowfall since the 1950s, indicating that Antarctic precipitation is not mitigating global sea level rise as expected, despite recent winter warming of the overlying atmosphere.

I wish I had a dollar for every time I've read that phrase: "...faster than previously thought."

It doesn't matter which scientist, which model, which theory, which observation -- they all seem to end up saying "but it's happening faster than we thought it would."

So whenever I hear a scientist predict a climate change condition "within the next (fill-in-the-blank) years", I automatically halve it, then shave off a few more years for good measure. As for the "we only have ten more years to stop this train," I think that train already left the station... as lot faster than we thought it would.