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Found in Wikipedia Commons - Source is Hannes Grobe at the Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany
Antarctic Weather
Antarctica is the southernmost continent on Earth, and since it’s home to the South Pole it is probably no surprise that the weather here is very cold—in fact, Antarctica is quite a bit colder than even the Arctic! Temperatures as low as -129 degrees F (-89 degrees C) have been recorded, and in the interior, near the South Pole, the average temperature is only -58 degrees F (-50 degrees C). Even in the summer the temperature rarely goes above -22 degrees F (-30 degrees C), so it’s easy to see why Ernest Shackleton said in 1909 that the weather in Antarctica was “A blinding, shrieking blizzard all day, with the temperature ranging from -60 to -70 degrees F.”There are a few reasons why Antarctica is so cold, especially as compared to the Earth’s Arctic regions. First, unlike the Arctic, Antarctica is a land mass, so a lot of the continent’s interior does not have the benefit of being surrounded by large expanses of liquid water (which has a moderating effect on climate). Second, the average elevation in Antarctica is actually very high—about 8500 feet— which results in lower surface temperatures. Third, like the Arctic, Antarctica absorbs very little solar radiation throughout the year— the snow and ice on its surface combine to reflect most the sun’s energy during summer, and during winter (March 22 throughout September 22) the sun doesn’t rise above the horizon at all because of the Earth’s tilt, so the whole continent stays dark.
Antarctica has also been called the windiest continent on Earth, though the winds vary a lot depending on location. There is generally a constant stream of cold air moving from the interior toward the continent’s coast, and as these currents move north they are pushed west by the Coriolis effect, producing winds that are called the Coastal Easterlies. Because the air in these currents is so cold, it is very dense, and the winds tend to flow along the surface of the land. In some places, where land features act as a funnel, the wind intensifies and becomes what is called a Catabatic wind, which can be very strong. One of these places, Cape Dennison at Commonwealth Bay, is one of the windiest places on Earth—the average windspeed is more than 50 mph, and winds as high as 200 mph have been recorded.
With all the ice and snow covering it, many people assume that Antarctica gets a lot of precipitation, but actually the opposite is true. The annual precipitation in Antarctica is so low that Antarctica is really a desert, and in fact the interior parts of the continent get less precipitation every year than the Sahara!
What does all this mean for us? It means that Antarctica may be the most inhospitable place on Earth for humans, and that it’s been a very difficult place to explore and study!
