A remote region in East Antarctica has
set a new record for the coldest place on Earth, with temperatures dipping to a
bone-chilling minus 93.2 degrees Celsius.
The
temperatures in several hollows of a high ridge in Antarctica on the East
Antarctic Plateau can dip below minus 92 degrees Celsius on a clear winter
night.
The new record of
minus 136 Fahrenheit (minus 93.2 C) was set on August 10, 2010, NASA said.
That is several degrees colder than the previous low of minus
128.6 F (minus 89.2 C), set in 1983 at the Russian Vostok Research Station in
East Antarctica.
Scientists
made the discovery while analysing the most detailed global surface temperature
maps to date, developed with data from remote sensing satellites including the
new Landsat 8, a joint project of NASA and the US Geological Survey (USGS).
Ted
Scambos, lead scientist at the National Snow and Ice Data Center in Boulder,
Colorado, joined a team of researchers who turned to sensitive satellite
instruments that can pick up thermal radiation emitted from Earth's surface,
even in areas lacking much heat.
Using
these sensors to scan the East Antarctic Plateau, Scambos detected extremely
cold temperatures on a 997 km stretch of the ridge at high elevations between
Argus and Fuji, and even colder temperatures lower elevations in pockets off
the ridge. Then, with the higher resolution of the Thermal Infrared Sensor
(TIRS) aboard Landsat 8, the research team pinpointed the record-setting
pockets.
Researchers
analysed 32 years' worth of data from several satellite instruments. They found
temperatures plummeted to record lows dozens of times in clusters of pockets
near a high ridge between Dome Argus and Dome Fuji, two summits on the ice
sheet known as the East Antarctic Plateau.
The
coldest permanently inhabited place on Earth is northeastern Siberia, where
temperatures in the towns of Verkhoyansk and Oimekon dropped to a bone-chilling
90 degrees below zero Fahrenheit (minus 67.8 C) in 1892 and 1933, respectively,
NASA said.
The
quest to find out just how cold it can get on Earth - and why - started when
the researchers were studying large snow dunes, sculpted and polished by the
wind, on the East Antarctic Plateau.
When
the scientists looked closer, they noticed cracks in the snow surface between
the dunes, possibly created when wintertime temperatures got so low the top
snow layer shrunk. This led scientists to wonder what the temperature range
was, and prompted them to hunt for the coldest places using data from two types
of satellite sensors.
The findings were presented at
the American Geophysical Union meeting in San Francisco.
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