Friday, 22 February, 2019

Coldest Place on Earth Found-Here's How

A mosaic of Antarctica. NASA  GSFC A mosaic of Antarctica. NASA GSFC
Theresa Hayes | 28 June, 2018, 19:00

In 2013, analysis of satellite data pinpointed scattered pockets of intensely cold air on the East Antarctic Plateau between Dome Argus and Dome Fuji - temperatures that dipped to a staggering minus 135 degrees Fahrenheit (minus 93 degrees Celsius).

However, the lowest recorded temperature in a weather station would be 89 degrees Celsius which was reported from Vostok Station, Russia in July 1983.

However, weather stations are not always reliable because they can't measure temperatures over an expansive area.

However, new analysis of the same data suggests that under the right conditions, those temperatures can drop to almost minus 148 degrees F (minus 100 degrees C), which is probably the coldest it can get on Earth, researchers reported in a new study.

The study took another look at temperature data that was taken between 2004 and 2016 during the Southern Hemisphere winter in the East Antarctic Plateau.

Remarkably, the lowest temperatures observed at all of these hollows on the ice sheet was right around minus 98 Celsius, even though some of them were spaced tens of miles apart.

The most recent findings released in the Geophysical Research Letters, this week, are showing that the valleys situated in the ice sheets of Antarctica can go closer to minus 100 degrees Celsius. In addition to a clear sky and light wind to reduce the temperature to such values, it is necessary that the air was very dry.

"There's a limit to how long the conditions persist to allow it to cool to these ultralow temperatures and a limit to how much heat you can actually get through the atmosphere, because water vapor has to be nearly nonexistent in order to emit heat from the surface at these temperatures", said Ted Scambos, a scientist at the National Snow and Ice Data Center and study lead author.

Antarctica's eastern plateau has the coldest temperatures on Earth. Water vapor concentrations in the atmosphere are increasing, which in turn means more of the ice-emitted heat gets trapped near the surface-keeping it warmer.

The brand-new nadir is formally minus 98 levels Celsius (minus 144 levels Fahrenheit), a temperature level that "seems around as reduced as it is feasible to get to" inning accordance with the worldwide group of scientists that dealt with the brand-new research study.

However, after NASA calibrated its system with more up-to-date weather station measurements, the researchers reanalyzed the temperature data. The weather conditions on the plateau did not change, but the adjusted satellite data gave the researchers a more accurate picture of what the actual lowest temperature was.

This allows the snow surface and the air above it to cool further, until the clear, calm, dry conditions change and the cold air mixes with warmer air higher in the atmosphere.

The new record-low temperature is probably about as cold as it can get on Earth.

But how cold can it get?

Very cold and dry air fills low-lying pockets and getting even colder. This is odd considering that some were located hundreds of kilometers apart.

However, they've designed new ground measurement equipment capable of dealing with the extreme cold, which they plan to deploy in the next two years.