Climate of Our Future

‘Remarkable’ Drop In Arctic Sea Ice Raises Questions

Science Daily — Melting Arctic sea ice has shrunk to a 29-year low, significantly below the minimum set in 2005, according to preliminary figures from the National Snow and Ice Data Center, part of the University of Colorado at Boulder. NASA scientists, who have been observing the declining Arctic sea ice cover since the earliest measurements in 1979, are working to understand this sudden speed-up of sea ice decline and what it means for the future of Earth’s northern polar region.

Polar ice reflects light from the sun. As this ice begins to melt, less sunlight gets reflected into space. It is instead absorbed into the oceans and land, raising the overall temperature, and fueling further melting. This results in a positive feedback loop called ice albedo feedback, which causes the loss of the sea ice to be self-compounding. The more it disappears, the more likely it is to continue to disappear. (Credit: NASA)

“The decline in the amount of thick ice that survives the summer melt season this year is quite remarkable,” said Josefino C. Comiso, senior scientist at NASA’s Goddard Space Flight Center, Greenbelt, Md. “The extent of this ‘perennial’ sea ice and the area it covers are both nearly 38 percent lower than average. Compared to the record low in 2005, the extent and area are 24 percent and nearly 26 percent lower this year, respectively.” Keep reading