The amount of ice covering the Arctic shrank to its lowest level on record this month, according to scientists at the National Snow and Ice Data Center (NSIDC).

The US-based scientists say new satellite images show the expanse of sea ice fell to 4.10 million square kilometres on 26 August, around 70,000 square kilometres below the previous lowest level recorded in September 2007.

While Arctic sea ice ‘extent’ varies from year to year because of changeable weather conditions, it has shown a “dramatic” overall decline over the past thirty years, according to the NSIDC.

The pronounced decline in summer Arctic sea ice over the last decade is considered by some to be a strong signal of long-term climate warming.

Experts believe the new record low could reveal “fundamental” changes in the Arctic.

NSIDC scientist Walt Meier said: “By itself it’s just a number, and occasionally records are going to get set. But in the context of what’s happened in the last several years and throughout the satellite record, it’s an indication that the Arctic sea ice cover is fundamentally changing.”

He added summer ice melting was becoming more common: “The Arctic used to be dominated by multiyear ice, or ice that stayed around for several years. Now it’s becoming more of a seasonal ice cover and large areas are now prone to melting out in summer.”

With two to three weeks left in the melt season, NSIDC scientists anticipate the minimum ice extent could fall even lower.