Arctic sea ice is melting so fast most of it could be gone in 30 years.

A new analysis of changing conditions in the region, using complex computer models of weather and climate, says conditions that had been forecast by the end of the century could occur much sooner.

A change in the amount of ice is important because the white surface reflects sunlight back into space. When ice is replaced by dark ocean water sunlight can be absorbed, warming the water and increasing the warming of the planet.

The finding adds to concern about climate change caused by human activities such as burning fossil fuels, a problem that has begun receiving more attention in the Obama administration and was part of the G20 discussions in London.

“Due to the recent loss of sea ice, the 2005-2008 autumn central Arctic surface air temperatures were greater than 5 degrees Celsius (9 degrees Fahrenheit) above” what would be expected, the new study reports.