Antarctic Sea Ice Extent Smashes Record
Sea ice extent surrounding Antarctica has smashed the previous record, covering more of the southern oceans than it has since satellite tracking started in 1979, according to NASA.
However, while the Antarctic is on an up swing, the Arctic is on a downward spiral, with sea ice decreasing in the wintertime twice as fast as what the Antarctic is increasing.
"The planet as a whole is doing what was expected in terms of warming. Sea ice as a whole is decreasing as expected, but just like with global warming, not every location with sea ice will have a downward trend in ice extent," Claire Parkinson, a senior scientist at NASA's Goddard Space Flight Center, said in a news release.
Some people see Antarctica's increasing trend as a sign that global warming isn't real, according to NASA research scientist Dr. Walt Meier, but that's simply not true.
Since the late 1970s, the Arctic has lost an average of 20,800 square miles (53,900 square km) of ice a year while the Antarctic has gained an average of 7,300 square miles (18,900 square km). And on Sept. 19, for the first time since 1979, Antarctic sea ice extent exceeded 7.72 million square miles (20 million square kilometers), a new record.
Even with the warming climate, changes in weather patterns can bring cool air to areas like the Antarctic, meaning it's possible for sea ice extent to grow, rather than melt.
"Part of it is just the geography and geometry. With no northern barrier around the whole perimeter of the ice, the ice can easily expand if conditions are favorable," Meier explained.
Scientists are still trying to understand the reasons for the increase in the Antarctic ice cover, suspecting that it's the result of a combination of factors, including changing wind patterns, snowfall, air pressure changes and even the hole in the ozone layer above Antarctica.
"The Antarctic sea ice is one of those areas where things have not gone entirely as expected," Parkinson said. "So it's natural for scientists to ask, 'OK, this isn't what we expected, now how can we explain it?'"
[Credit: NASA Goddard]