A strong El Nino and warmer temperatures pushed back lake freeze dates for the Northeast and Midwest areas of the United States, a water scientist said.
El Nino's stronger-than-expected warming in the equatorial waters of the Pacific Ocean occurs roughly every three to seven years, Kenton Stewart, a University of Buffalo scientist, said in a news release. Some of the ocean water's extra heat may be transferred through the atmosphere to regions around the United States.
Initial predictions were for a relatively mild El Nino, he said, but now it is shaping up to be a strong El Nino year similar to the winter of 1997-98.
"General overall temperatures are rising and so there may come a time when these little lakes do not freeze at all," said Stewart.
A colder-than-normal period in early December caused many lakes in Minnesota and Wisconsin to develop ice covers, Stewart said. Some of those lakes are still frozen but others have since lost all or part of their ice because of the unusually warm temperatures in late December and the relatively mild start to 2007.
Copyright 2007 by United Press International
Explore further: Abundance of Chesapeake Bay's underwater grasses increases