Why is antarctica so cold?

Why is Antarctica the way it is? or how is it that Antarctica is so cold?

Antarctica has its features mainly due to its location at the South Pole. The South Pole tends to get significantly less sunlight than other places, this is similar to the North pole too. Less sunlight means it gets cold. In addition the permanent ice cap reflects a large amount of sunlight.

Also Antarctica is on average the highest continent and so temperature decreases with altitude. The Southern ocean is somewhat colder than the northern oceans also maintaining cooler temperatures.


antarcticarelief.jpg

This shows how high Antarctica is. Purple is sea level  pink is about 4000metres. image: USGS.gov 

Antarctica is also quite an isolated continent. There are no major land masses near by, although the peninsula of South America does come very close, the shape of the Peninsula means there is very little land mass to hold heat or cause changes in weather.

the arctic has larger land masses that extend away towards the equator.image: wikipedia

Pole-south.gif

The antarctica  has no large land mass near by. image: wikipedia


antweather.jpg

This weather chart of Antarctica shows very intense low air pressures and high pressure systems that produce very high wind speeds. The isobars are close together and indcated rapid change in pressures.

 image: Australian Bureau of Meteorology, Antarctica


Due to the high average elevation in Antarctica there is also less atmospheric pressure, lower air pressures that contribute to keeping the region cold.


catabatic.jpg

The high average elevation height allows cold air to fall down and off Antarctica (this is called Katabatic wind - the Greek word for going down hill. image: wikipedia


Coldest place on Earth

The coldest temperature on Earth has been recorded from satellite data. It measured a chilly -93.3°C (-136°F ) on August 10, 2010. It came from 32 years of satellite data analysis. The cold spot was found in  pockets of trapped air on the East Antarctic Plateau. 

One the reasons the pocket of air was so cold was due to clear nights allowing more heat to radiate out of the atmosphere into space. This is the same reason why deserts get cold at night.

The previous record was -89.2°C , in 1983 at the Russian Vostok Research Station in East Antarctica and was a little lower down than the plateau region of the new record.


Reference: