Sea surface temperatures from Cape Hatteras, N.C., to the Gulf of Maine were the highest ever recorded from January through June, federal officials said Tuesday.
Above-average temperatures were pervasive, from the ocean’s floor to the surface, across the region and outward beyond the continental shelf, according to the National Oceanic and Atmospheric Administration Northeast Fisheries Science Center.
The average sea surface temperature exceeded 51 degrees Fahrenheit during the first half of 2012, Kevin Friedland, a scientist with the center’s Ecosystem Assessment Program, said in a printed advisory.
The previous record high was in 1951. The average has typically been lower than 48 degrees Fahrenheit in the last three decades.
“This will have a profound impact throughout the ecosystem,” Friedland said.
In the same time period, for example, the annual spring plankton bloom was long and intense along the Northeast, and the bloom started earlier and lasted longer than average, according to the NOAA center. In some areas the spring bloom started as early as February.
“That goes along with what we observed in Cape Cod Bay in the winter,” Charles “Stormy” Mayo, who heads the right whale habitat studies at the Provincetown Center for Coastal Studies, said Tuesday.
“It was an unusual winter. We saw some differences in the zooplankton. The right whales came into Cape Cod Bay the earliest in the history of our work, since 1984. In this complex world, you can never say this is because the temperature has changed but it’s not a hard conclusion to come up to.”
Sea surface temperature measurements are based on satellite remote-sensing data and long-term measurements from aboard ships. Historical records from shipboard data date from 1854.
Ocean bottom temperatures in 2012 were the warmest since 2001, according to data produced from a cooperative research program between the NOAA center and lobstermen who deploy temperature probes attached to lobster traps.
Atlantic cod distribution in the Gulf of Maine continued a northeasterly shift, which federal officials said is expected in response to the warming of an ecosystem. Cod haven’t shifted as much as other species, such as hake, but that could change with warming waters and changes in ocean circulation patterns, the NOAA center said.
About half of 36 fish stocks studied in the Northwest Atlantic Ocean have been shifting northward over the past four decades, with some disappearing from U.S. waters, the center said.
“The big question is whether or not these changes will continue, or are they a short-term anomaly?” Friedland said.
The NOAA ecosystem advisories are issued twice a year to provide an overall snapshot of the ecosystem for fishery management councils, fishermen, researchers and others.
“Undoubtedly we know this is coming, in terms of warmer temperatures,” Jon Kachmar, director of the southeastern Massachusetts office of The Nature Conservancy in Plymouth. “It’s really a changing system.”
The nonprofit organization wants to ensure that natural habitats in the region can support the needs of species that will end up here in the future, given warming temperatures.
“We know we need to adapt,” Kachmar said.
Changing fish population
Glen Gawarkiewicz, a scientist of physical oceanography at the Woods Hole Oceanographic Institution, was on a scientific cruise in May off North Carolina where the water temperatures were 9 degrees warmer than a cruise in the same location in 1996, according to the Associated Press.
During the May cruise, scientists were unable to find bluefish and butterfish they were looking for, but instead found warmer-water fish including amberjack and blue runners that normally wouldn’t have been there, Gawarkiewicz told AP.
It’s unclear exactly why the ocean temperatures are rising as they are, he said. Perhaps more importantly, it’s also unclear if the change is long-term or a short-term anomaly.
“That’s the $64,000 question,” he said.
(c)2012 Cape Cod Times (Hyannis, Mass.)
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