North Atlantic 'Cold Blob' a Reason for Concern, Scientists Say

Some experts theorize that the cold water south of Iceland shows the Atlantic Ocean's circulation is slowing...In short, warm and cold water should work together to balance out the temperature of the oceans...But the massive ice melt occurring in the Arctic has introduced a lot of cold, fresh water into the mix, and it's not behaving the same as cold salt water. It's preventing the sinking that usually happens with cold water, as fresh water is less dense than salt water, and that could be weakening the circulation.