A Century of Data Shows Warming on the Islas Orcadas since 1950
22.01.2010 - Atmosphere & Space, Antarctic
More than a century’s worth of weather data from a base at the Islas Orcadas off the tip of Antarctica have revealed a spike in warming there since 1950. The base, which was founded by Scots in 1903, has been collecting daily weather data for over a century, giving scientists with a better understanding of climate change in the southern hemisphere.
The records, which are especially useful in revealing extremely warm and cold weather days, which are usually lost in the easier-to-locate monthly mean records. The record further shows that there have been changes in the actual cycles and that summers at the base have become increasingly warmer since the 1950s.
The warming in the Orcadas has not been primarily caused by global warming, however, but rather by the hole in the ozone layer which has been forming over Antarctica every austral spring since the 1970s. This hole has been cooling the stratosphere over Antarctica, which in turn has been reinforcing the “polar vortex”, a circular cold air mass that can form above Antarctica. The Orcadas, which are located outside of the polar vortex, find themselves in a special situation, receiving much fewer waves of cold air as a consequence.
