Nasa discovers coldest place on earth december 2013
December 10, 2013 – ANTARCTICA – NASA
announced the discovery of the coldest place on Earth after examining
global surface temperature data collected over a period of 32 years by
remote sensing satellites including the new Landsat 8. The coldest spot
identified is a high ridge located on the East Antarctic Plateau where
the temperatures drop below -133.6 degree Fahrenheit during winters.
This new record temperature on the icy plateau was set on Aug.10, 2010.
The research team was led by Ted Scambos, lead scientist at the National
Snow and Ice Data Center in Boulder, Colo., who discovered that the
temperatures dropped to a record of low, several times, in clusters of
pockets near an ice ridge located between Dome Argus and Dome Fuji, two
ice summits on the East Antarctica Plateau. “We had a suspicion this
Antarctic ridge was likely to be extremely cold, and colder than Vostok
because it’s higher up the hill,” Scambos said in a statement. “With the
launch of Landsat 8, we finally had a sensor capable of really
investigating this area in more detail.” The new record is in fact
several degrees colder than the previous low of -128.6 Fahrenheit that
was set at the Russian Vostok Research Station in East Antarctica in
1983.
Scientists discovered this coldest spot
on Earth while studying the large snow dunes formed by winds blowing
across the East Antarctic Plateau. On a closer look they spotted cracks
present in the snow surface between the dunes that most likely form when
the temperatures during the winter fall so low that the snow layer
present on the top shrinks. This ignited a curiosity in the scientists
to estimate the range of temperatures and pushed them to look for
coldest places on Earth using two kinds of satellite sensors. “The
record-breaking conditions seem to happen when a wind pattern or an
atmospheric pressure gradient tries to move the air back uphill, pushing
against the air that was sliding down,” Scambos said. “This allows the
air in the low hollows to remain there longer and cool even further
under the clear, extremely dry sky conditions,” Scambos said. “When the
cold air lingers in these pockets it reaches ultra-low temperatures.”
The two sensitive instruments namely, the Moderate Resolution Imaging
Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites and the
Advanced Very High Resolution Radiometer (AVHRR) on the NOAA satellite
have the capacity to identify the thermal radiation that is emitted from
the surface of the Earth, even in those regions that lack heat. -SWR
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