"0BZN0" <0BZN0@[EMAIL PROTECTED]
> wrote
> ... in a tiny, tiny corner of Antarctica!!!!!!
> The rest of Antarctica is growing and cooling.
NASA finds evidence of widespread Antarctic melting
Last Updated: Wednesday, May 16, 2007 | 10:04 AM ET
Rising temperatures two years ago led to widespread melting of snow cover
in
west Antarctica, according to scientists examining the impact of global
warming on the icy continent.
The melting of snow cover in regions in January 2005 was the most
significant Antarctic melting seen since satellites began observing the
continent three decades ago, NASA said Tuesday.
NASA's QuikScat satellite detected extensive areas of snowmelt, shown in
yellow and red, in west Antarctica in January 2005.
(NASA/JPL) It was also the first major melting detected using NASA's
QuikScat satellite, which can measure both ac***ulated snowfall and
temperatures in various regions.
The team of scientists found evidence of melting in regions not normally
affected: up to 900 kilometres inland from the open ocean, farther than 85
degrees south (within 500 kilometres of the South Pole) and higher than
2,000 metres above sea level.
QuikScat found maximum air temperatures at the time of melting were
unusually high, reaching more than 5 C in one of the areas. These maximum
temperatures remained above the melting point for approximately a week.
The researchers were led by Son Nghiem of NASA's Jet Propulsion Laboratory
and Konrad Steffen, the director of the Co-operative Institute for
Research
in Environmental Sciences at the University of Colorado. They published
their results in a book, Dynamic Planet.
"Antarctica has shown little to no warming in the recent past, with the
exception of the Antarctic Peninsula, but now large regions are showing
the
first signs of the impacts of warming as interpreted by this satellite
analysis," said Steffen in a statement.
"Increases in snowmelt, such as this in 2005, definitely could have an
impact on larger-scale melting of Antarctica's ice sheets if they were
severe or sustained over time."
The 2005 melt was extensive enough to create a layer of ice when the water
refroze, but was not long enough for the water to flow to the sea. Steffen
said if enough water from melted snow is created, it could slip through
the
cracks of the continent's ice sheets and potentially affect their
movement.
The Antarctic ice mass is the Earth's largest freshwater reserve, and
changes in its condition can have an impact on sea levels, ocean salinity
and water currents.
"We need to know what's coming in and going out of the ice sheets," said
Ngheim.
"QuikScat data, combined with data from NASA's IceSat and Gravity Recovery
and Climate Experiment satellites, along with aircraft and ground
measurements, all contribute to more accurate estimates of how the polar
ice
sheets are changing."
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