The North Pole's ice skull cap shrank to an historic low this week. Shrinking to its lowest point since satellite observations began in 1972, the area covered by the Arctic sea ice shrank to 4.24 million square kilometers (1.637 square miles) on Sept. 8, according to the University of Bremen's Institute of Environmental Physics.

The historic low measurement is about a half-percent below the previous record low set in September, 2007, the institute said.

The shrinking Arctic ice cover has also become significantly thinner in recent decades, but the institute says it's not possible to measuring in thickness as specifically as they can on the surface area.

Results are described by scientists as a measure and driving factor of global warming. They say the fast-shrinking Arctic skull cap has both local and planetary implications.

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

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. 

Studies show the cultprit for the shrinking Arctic cap are rising temperatures in the region -- temperatures which have risen twice as fast as the global average in the last half of the century. Thus, the the Arctic skull cap and Arctic ice cover are both reducing at a fast pace, the institute said.

The U.S. National Snow and Ice Data Center also tracks Arctic ice cover on a daily basis but that agency has not announced a record low ice cover yet.