NASA scientists have long been tracking Arctic sea ice, which has been significantly retreating over recent years. June, which brings about the start of the melting season, established a record low in 2005 for sea ice cover -- 6 percent below average.

• NASA Earth Observatory. "Record Low for June Arctic Sea Ice." June 2005 at earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=16978 

While, historically, the ice has always regained coverage during the wintertime, recent years' warming has prevented such recovery. Arctic sea ice has been markedly decreased in the winter months as well as in the summer months. Following the trend set over the past few years, 2005 will likely be yet another year characterized by record low sea ice concentrations, according to NASA predictions.

Implications: The melting of sea ice is occurring more rapidly than heretofore predicted. Ice melting leads to changes in ocean salinity, freshening ocean waters and potentially contributing to changes in thermohaline circulation (the ocean's conveyer belt effect that moves equatorial heat to the north, warming Europe). Consistent with the trend in decreased sea ice concentrations, the study's results foreshadow a future of low sea ice cover with increasing concomitant effects.