Bad Antarctic weather

February 14, 2011

An Antarctic blizzard.

As we all know, Antarctica is cold. The principal reason for its being cold is, of course, its high southern latitude, but to this are added a number of other augmenting factors: the air is extremely dry, so solar energy is not absorbed by surface-level water vapour; the continent is mostly covered with snow and ice, which reflects the solar energy away; there are no major bodies of inland water, which would tend to have a moderating influence; and Antarctica has a high average surface elevation.

When we say that it is cold down there, we mean it. The mean temperature in the interior of Antarctica is –57°C (–70°F). Temperatures on the coastal areas are milder, but still chilly: at McMurdo Station on Ross Island, for instance, the average temperature in August is just –28°C (–18°F), though in January it rises to –3°C (27°F). Temperatures tend to be higher still on the Antarctic Peninsula, which stretches furthest north.

As an illustration of these general features, the miracle of the Hinternet allows us to check the current conditions at several Antarctic locations:

Sure enough, it’s cold.

As I mentioned in an earlier post, Antarctica is technically classified as a desert, and this despite its being almost totally covered in frozen water. The reason is that its average annual precipitation is very low: less than 5 cm (2 in). This is comparable to the Sahara. There are a few rare spots in Antarctica, called ‘dry valleys’, that are not snow-covered; it is estimated that it has not rained in these spots for about 2 million years.

Antarctica has terrific storms. In the winter the wind-chill temperature can fall to –100°C (–150°F). Blizzard conditions can reduce visibility to the length of one’s arm, and the storms can continue for weeks. The fierce blizzards are compatible with the low precipitation: they tend to consist of blowing, rather than falling, snow.

Finally, it is worth noting (again) that the coldest naturally occurring terrestrial temperature ever measured was in Antarctica, at the Russian Vostok Station. That temperature was –89.2°C (–128.6°F).

With such thoughts in mind on this St. Valentine’s Day, why not stay warm by snuggling up under a blanket with your sweetheart?

2 Responses to “Bad Antarctic weather”

  1. Mac Says:

    I sat here for a few moments, getting fidgety because that graphic was taking so long to load, before I noticed the caption.

    It’s very bold of you to follow those weather station links with “Sure enough, it’s cold.” Maybe someday someone will click on one and find that the temperature is above freezing.

  2. cburrell Says:

    Oh, that’s not very likely.

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