Sea ice has been increasing in the Antarctic, but it's not making up for losses in the Arctic sea, a new NASA study has found.
Ice increases just can't keep up with the rate at which ice is lost at 13,500 square miles every year, an area of ice bigger than the state of Maryland.
Claire Parkinson is a climate scientist from the NASA Goddard Space Flight Center and the author of the study. By using microwave data gathered by the Department of Defense and NASA's satellites, she added the rates at which the Antarctic and Arctic sea ice grew every month between November 1978 and December 2013.
The results of the study showed that over the course of 35 years, ice grew less in all of the months of the year, even at points when sea ice in the Antarctic and Arctic were at their highest levels.
Additionally, the rate at which ice being lost during the first half of the study is less than half of the rate from the second half. If, from 1979 to 1996, ice was being lost at around 8,300 square miles each year, then this number grew to 19,500 square miles per year from 1996 to 2013, which is like losing the same amount of ice as a sheet bigger than the states of New Hampshire and Vermont combined.
Parkinson also showed in the study that the rate at which ice grows annually around the world closely resembles the Antarctic ice cycle. Ice grows the least globally during February of every year, the same with the Antarctic's cycle, and the most during either October or November, a month or two after the most ice has developed in the Antarctic.
The Arctic, on the other hand, undergoes an ice cycle that sees the least growth in September and the most in March.
Decreasing sea ice is a concern because it will cause water levels around the world to rise. The study, however, also highlighted a different but related concern, explaining that the loss of sea ice is important because it plays a role in global warming, and is not just an effect.
"Sea ice is highly reflective whereas the liquid ocean is very absorptive," said Parkinson.
When the ice sheet shrinks, then a smaller area is left to reflect the sun's rays back into space. With more water instead, heat will be retained and radiated within the planet.
The trend also isn't likely to change in the future, she added.
