The core of the Gulf Stream diverted as much as 125 miles to the north of its average position last year.
Last fall, fishermen in the Northeast United States noticed stronger currents and higher water temperatures than usual, so they tapped scientists from the Woods Hole Oceanographic Institution in Massachusetts to help them find out what was going on.
A study by the scientists, published recently in the journal Scientific Reports, suggests the cause was a change in the direction of the Gulf Stream, the current that ferries warm water from the Gulf of Mexico northeast into the Atlantic and along the U.S. East Coast. The scientists found that the center, or core, of the Gulf Stream was diverted as much as 125 miles (200 kilometers) to the north of its average position, according to a WHOI statement.
In late October 2011, temperatures increased at two deep-water sensors attached to lobster traps off Nantucket by as much as 12 degrees Fahrenheit (6.7 degrees Celsius) over the course of several days. That pushed water temperatures above 64 F (18 C), which is very unusual in the waters off southern New England for that time of year. It's also 4 F (2 C) higher than temperatures have been at one of these locations in the last decade, said study author and WHOI researcher Glen Gawarkiewicz.