The amount of Arctic sea ice has melted to a historic low, with the area of land covered by ice at the smallest level since scientists began observing it with satellites in 1972, researchers from the University of Bremen in Germany report.
The North Pole skull cap shrank to about half a percent under the previous record low set in September 2007, according to the school's Institute of Environmental Physics.
Researchers, including those from the National Snow and Ice Data Center, had predicted earlier this summer that Arctic sea ice levels could reach extreme lows. But the University of Bremen physicists said there was uncertainty in July about whether the ice melt would surpass the previous record.
They said their studies indicated that continuing ice decline was related to man-made global warming.
"It seems to be clear that this is a further consequence of the man-made global warming with global consequences," researchers said in their report. "Directly, the livehood of small animals, algae, fishes and mammals like polar bears and seals is more and more reduced."
As Arctic sea ice has continued to decline, it also has become drastically thinner overall, the report said.
The researchers said that previously the melting ice had been attributed to yearly weather anomalies. But now it is believed the massive melt is due in part to global warming and the increasing albedo effect, which has to do with the power of the surface to reflect sun. As more ice melts, instead of having white ice reflect more of the sun's rays, you have a larger amount of open water that absorbs those same rays. Therefore, warmer temperatures lead to even more ice melting.
The National Snow and Ice Data Center did not have updated data to confirm the German report but said it expected the historic low to be hit based on the past few weeks' data. Its site is only up to date to September 6. The historic levels were reached two days later. The center said it would "make a preliminary announcement when ice extent has stopped declining and has increased for several days in a row" and said it would release monthly data for September early next month.
The large-scale thaw is cause for concern, according to Shaye Wolf, climate science director of the Center for Biological Diversity’s Climate Law Institute.
“This stunning loss of Arctic sea ice is yet another wake-up call that climate change is here now and is having devastating effects around the world,” Wolf said in a statement.
The Climate Law Institute noted the record followed news that this summer was the second-hottest since 1895.
In 2009, studies began suggesting the Arctic Ocean could be "largely ice free" during summer within a decade.
One of those reports, complied by the UK-based Catlin Arctic Survey and the World Wildlife Fund, showed that researchers predicted that within 20 years ice cover will be completely gone during the warmer months.