Arctic sea ice 'thinning faster than expected'

Sea ice in the Arctic's coastal regions may be thinning up to twice as fast as previously thought, France 24 reports, citing a new study highlighting worrying implications for climate change.

The analysis, led by researchers at Britain's University College London (UCL), concluded the ice in the coastal regions was thinning at a rate 70 to 100 percent faster than the established consensus.

The dramatic reassessment comes after the team used more up-to-date maps of snow depth on the ice, which has been retreating for decades as the planet warms.

"We believe our new calculations are a major step forward in terms of more accurately interpreting the data we have from satellites," said UCL professor Julienne Stroeve, who co-authored the study published in The Cryosphere journal.

"We hope this work can be used to better assess the performance of climate models that forecast the effects of long-term climate change in the Arctic," she said.

The region, home to millions of square kilometres of ice essential for keeping the planet cool, is warming at three times the global rate, Stroeve said.

Sea ice thickness is estimated by measuring the height of the ice above the water. But that measurement is distorted by snow weighing the ice floes down.

Scientists had adjusted for this using a map of snow depth in the Arctic that UCL said did not account for the impact of climate change.

"Previous calculations of sea ice thickness are based on a snow map last updated 20 years ago," said Robbie Mallett, a PhD student who led the study.

"Because sea ice has begun forming later and later in the year, the snow on top has less time to accumulate.

"Our calculations account for this declining snow depth for the first time, and suggest the sea ice is thinning faster than we thought."