The American National Science Foundation (NSF) has published research that indicates that Artic sea ice melt could temporarily stabilize or expand at times over the next few decades.

 

Results of a study by scientists at the National Center for Atmospheric Research (NCAR) reinforce previous findings that Arctic sea ice loss is not simply the result of climate variability, but rather is also a result of carbon production.

 

"As we learn more about climate variability, new and unexpected research results are coming to light," says Sarah Ruth, program director in the Division of Atmospheric and Geospace Sciences, which funds NCAR for NSF. "What's needed now are longer-term observations to better understand the effect of climate change on Arctic sea ice."

 

But in an unexpected new result, the NCAR research team found that Arctic ice under current climate conditions is as likely to expand as it is to contract for periods of up to about a decade.

 

"One of the results that surprised us all was the number of computer simulations that indicated a temporary halt to the loss of the ice," says NCAR scientist Jennifer Kay, the lead researcher.

 

Ms Kay explains that variations in atmospheric conditions such as wind patterns could, for example, temporarily halt the sea ice loss. Still, the ultimate fate of the ice in a warming world is clear, Ms Kay says.

 

"When you start looking at longer-term trends, 50 or 60 years, there's no escaping the loss of ice in the summer."


Kay and her colleagues then conducted a series of future simulations that looked at how Arctic sea ice was affected both by natural conditions and by the increased level of greenhouse gases in the atmosphere.

 

The computer studies indicated that the year-to-year and decade-to-decade trends in the extent of sea ice are likely to fluctuate increasingly as temperatures warm and the ice thins.

 

By analyzing multiple realizations of the 20th century from a single climate model, they attribute approximately half the observed decline to human emissions of greenhouse gases, and the other half to climate variability.