Despite a cooling trend in the East Antarctic Ice Sheet, Antarctica has experienced net warming over the past 50 years, report researchers writing in the January 22 edition of Nature.
Analyzing data from satellites and weather stations authors led by Eric Steig of the University of Washington (UW) found that “warming in West Antarctica exceeded one-tenth of a degree Celsius per decade for the last 50 years and more than offset the cooling in East Antarctica”, according to a statement from UW.
The researchers attribute the diverging trends to differences in elevation and geography between East Antarctica and West Antarctica as well as the influences of the hole in the ozone layer, which has a cooling effect.
This illustration depicts the warming that scientists have determined has occurred in West Antarctica during the last 50 years, with the dark red showing the area that has warmed the most. (Image Credit: NASA)
“West Antarctica is a very different place than East Antarctica, and there is a physical barrier, the Transantarctic Mountains, that separates the two,” said Steig. With an average elevation of more than 10,000 feet, East Antarctica is considerably higher than the West Antarctic Ice Sheet, which is “subject to relatively warm, moist storms and receives much greater snowfall than East Antarctica”.
Steig suggests the data undermines those who cite cooling in Antarctica to cast doubt on whether the planet is warming.
“The thing you hear all the time is that Antarctica is cooling and that’s not the case,” he said. “If anything it’s the reverse, but it’s more complex than that. Antarctica isn’t warming at the same rate everywhere, and while some areas have been cooling for a long time the evidence shows the continent as a whole is getting warmer.”