ELLSWORTH, Maine — Dating back to the Civil War, when official data began to be collected, the waters along the Northeast coast of the United States have never been so warm as they were in 2012, according to federal officials.
Modern measurement methods may be technologically advanced, but scientists with the National Oceanic and Atmospheric Administration have shipboard measurements that date to 1854 of sea surface temperatures between Cape Hatteras and the Canadian border. Last year, temperatures in the region, known as the Northeast Shelf Ecosystem, reached a record high of 14 degrees Celsius or 57.2 degrees Fahrenheit, the agency indicated in a prepared statement released this week. Over the past three decades, the average such temperature in the NSE typically has been lower than 12.4 degrees Celsius or 54.3 degrees Fahrenheit.
“The temperature increase in 2012 was the highest jump seen in the time series [since 1854] and one of only five times [that] temperature has changed by more than 1 degree Celsius” or 1.8 degree Fahrenheit, the statement said.
Data collected from the Gulf of Maine indicates that the average sea surface temperature in the gulf has risen 1.5 degrees from 2011 to 2012 and that in the past four years, it has risen between 2 and 3.5 degrees, depending on how one looks at the data collected from scientific studies.
With the rising temperatures come concerns, and some indication, about how marine life along the coast will be affected.
Officials and scientists in Maine have suggested that higher temperatures in the Gulf of Maine have been a factor in bacterial outbreaks in bivalves and in sea lice infestations in Cobscook and Passamaquoddy bays. Some have put partial blame on the gulf’s warmer waters for a northeasterly shift of cod in the gulf into colder waters, for declining shrimp catches and for the glut of soft-shell lobsters last summer that caused a plummet in prices lobstermen were receiving for their catch.
People involved in Maine’s elver fishery believe warm temperatures last year contributed to the high annual elver landings total — more than 19,000 pounds — which is at least double the volume harvested in any other year since 1998, when 14,400 pounds were caught in Maine.
According to officials with NOAA’s Northeast Fisheries Science Center, temperature changes also appear to have had an effect on black sea bass, summer flounder, longfin squid and butterfish, all of which have shifted “upshelf,” or to the northeast.
“Many factors are involved in these shifts, including temperature, population size, and the distributions of both prey and predators,” Jon Hare, a scientist in NEFSC’s Oceanography Branch, said in the statement.
Over the past 40 years, roughly half of 36 fish stocks in the northwest Atlantic Ocean studied by NEFSC have shifted northward, the statement added.
Another factor related to ocean temperature that could have an impact on fish and other marine species is the timing and strength of plankton blooms, according to NOAA. The anticipated bloom this spring of plankton, microscopic organisms that comprise the bottom of the marine food chain, is expected to be affected by last year’s water temperatures, scientists have indicated.
NEFSC scientist Kevin Friedland indicated that the contrast between subsequent years with and without a fall plankton bloom is emerging as an important factor in the ecology of the Northeast ocean shelf.
“The size of the  spring plankton bloom was so large that the annual chlorophyll concentration remained high [for the year] despite low fall activity,” Friedland said in the release. “These changes will have a profound impact throughout the ecosystem.”