PARIS: The area covered by Arctic sea ice reached it lowest point this week since the start of satellite observations in 1972, German researchers announced on Saturday.

On September 8th, the North Pole’s icy skull cap shrank to 4.24 million square kilometres (1.637 million square miles), about half-a-per cent under the previous record low set in September 2007, according to the University of Bremen’s Institute of Environmental Physics.

The Arctic’s dwindling summer sea ice is described by scientists as both a measure and a driver of global warming, with negative impacts on a local and planetary scale.

It is also further evidence of a strong human imprint on climate patterns in recent decades, the researchers said.

“The sea ice retreat can no more be explained with the natural variability from one year to the next, caused by weather influence,” Georg Heygster, head of the Institute’s Physical Analysis of Remote Sensing Images unit, said in a statement.

“Climate models show, rather, that the reduction is related to the man-made global warming which, due to the albedo effect, is particularly pronounced in the Arctic.”

Albedo increases when an area once covered by reflective snow or ice -- which bounces much of the Sun’s radiative force back into space -- is replaced by deep blue sea, which absorbs the heat instead.

Temperatures in the Arctic region have risen more than twice as fast as the global average over the last half century.

The Arctic ice cover has also become significantly thinner in recent decades, though it is not possible to measure the shrinkage in thickness as precisely as for surface area, the statement said.

The US National Snow and Ice Data Center, which likewise tracks Arctic ice cover on a daily basis, has not announced a record low ice cover. Data posted on its website only covered the period through September 6.