There's big news in Antarctic research this week. A study by several scientists and published by Nature magazine this week has found substantial evidence that the Antarctic continent has experienced an overall warming comparable to that occurring in the rest of the world. While some areas of the continent are in fact cooling, the general trend is heading in the opposite direction, particularly in West Antarctica. Previous studies have also indicated a warming trend in Antarctica, but this study is different and important because it combines old, sparse temperature records with satellite records to create an overall temperature picture from the past fifty years. Previous studies have only analyzed temperatures from between 20 and 30 years ago because of the insufficiency of temperature records. Because Antarctica is so huge, many of the temperature records from further back were from locations too far apart to present a clear picture. The combination of satellite records and older temperature records allowed the researchers to develop a longer, more comprehensive picture of Antarctic temperature trends.
Update: Talk of the Nation: Science Friday featured one of the lead authors of this paper on their 1/23/09 broadcast. Listen here.
NPR also has a good story on the study here.
In response to some criticisms of their study, two of the authors have posted further explanations of the implications of their research on the Real Climate blog. Their research doesn't contradict earlier research showing cooling trends in East Antarctica. It's helpful to remember that even though all of Antarctica is cold, it is big enough that weather patterns are going to vary widely, just as they do in other large countries. So trends in one region aren't necessarily the whole story. Much of the cooling in the east is theorized to be the result of the ozone hole, which developed in the 1970s and will no doubt grow smaller now that CFCs have been banned. They also note that their paper doesn't explore whether the warming of the past 50 years is part of a larger trend. In a sense, it may not need to. Since it has clarified that Antarctica has not escaped the global warming trend, it already contributes to reinforcing the idea that global warming is indeed global.