Ocean-surface temperatures along the Northeastern coast of the US are higher now than at any time since record keeping began 150 years ago, according to the National Oceanic and Atmospheric Administration (NOAA).
This isn’t a surprise of course, “high sea surface temperatures (SSTs) are the latest in a trend of above average temperature seen during the spring and summer seasons, and part of a pattern of elevated temperatures occurring in the Northwest Atlantic.”
“Sea surface temperature for the Northeast Shelf Ecosystem reached a record high of 14 degrees Celsius (57.2°F) in 2012, exceeding the previous record high in 1951. Average SST has typically been lower than 12.4 C (54.3 F) over the past three decades.”
The temperature data was collected via satellite remote-sensing, and ship-board measurements. The historical SST data is “based on ship-board measurements dating back to 1854.” The temperature rise in 2012 was the most prominent jump in temperature observed in all of the time series, and one of only a few times that temperature changed by more than 1 C (1.8 F).
“The Northeast Shelf’s warm water thermal habitat was also at a record high level during 2012, while cold water habitat was at a record low level. Early winter mixing of the water column went to extreme depths, which will impact the spring 2013 plankton bloom. Mixing redistributes nutrients and affects stratification of the water column as the bloom develops.”
The rising temperature has been having a considerable effect on the distributions of various fish and shellfish. Four important “southern species — black sea bass, summer flounder, longfin squid and butterfish — (have) all showed a northeastward or upshelf shift. American lobster has shifted upshelf over time but at a slower rate than the southern species. Atlantic cod and haddock have shifted downshelf.”
“Many factors are involved in these shifts, including temperature, population size, and the distributions of both prey and predators,” stated Jon Hare, a scientist in the NEFSC’s Oceanography Branch. “A number of recent studies have documented changing distributions of fish and shellfish, further supporting NEFSC work reported in 2009 that found about half of the 36 fish stocks studied in the Northwest Atlantic Ocean, many of them commercially valuable species, have been shifting northward over the past four decades.”
“The Northeast U.S. Continental Shelf Large Marine Ecosystem (LME) extends from the Gulf of Maine to Cape Hatteras, North Carolina. The NEFSC has monitored this ecosystem with comprehensive sampling programs since 1977. Prior to 1977, this ecosystem was monitored by the NEFSC through a series of separate, coordinated programs dating back decades.”
“Changes in ocean temperatures and the timing and strength of spring and fall plankton blooms could affect the biological clocks of many marine species, which spawn at specific times of the year based on environmental cues like water temperature,” Kevin Friedland, a scientist in the NEFSC Ecosystem Assessment Program, said. Noting that the difference between the years featuring, and not featuring, a fall bloom is seen as one of the most important drivers of the shelf’s ecology. “The size of the spring plankton bloom was so large that the annual chlorophyll concentration remained high in 2012 despite low fall activity. These changes will have a profound impact throughout the ecosystem.”
“What these latest findings mean for the Northeast Shelf ecosystem and its marine life is unknown,” Fogarty said. “What is known is that the ecosystem is changing, and we need to continue monitoring and adapting to these changes.”
Climate change is predicted to have a considerable effect on the health of various commercially important fisheries around the world within the near-future. When this is combined with the over-fishing that is prevalent throughout much of the world, the future of fish as a commercially important resource is very questionable.