The sight of a polar bear clinging to an ice floe as its habitat slowly begins to disappear is one of the most iconic images demonstrating the effects of global warming. While other parts of the world may see bizarre weather patterns that don't seem immediately linked to the earth's temperature, the melting of the polar ice caps in the Arctic circle sends a clear message: the world is getting warmer.
Using satellite images of the Arctic circle, the analysts at the U.S National Snow and Ice Data Center (NSIDC) have been monitoring the ebbs and flows of the region's sea ice – which sits just below the water's surface – since 1979. Walter Meier, an NSIDC research scientist, told Wynne Parry of LiveScience that sea ice levels generally rise and fall in line with the seasons.
However, overall sea ice levels have been on the decline in the last few years. The source states that the lowest recorded ice level was in 2007, but the second lowest measurement was reached last year. And though Meier was quick to say that it was too soon to tell if this year would surpass the 2007 record, downward trend makes it a real possibility.
The scientific community has been speculating about the cause for this decline ever since levels first began to plummet. Currently, most scientists have settled on two joint causes: natural weather patterns and global warming.
The melting of arctic ice has already had a detrimental effect on arctic wildlife, but it could also harm the rest of the world too. Because ice naturally reflects the sun's rays while water simply absorbs them, the source states that the rate of global warming may actually increase as a result of lower ice levels.