Would you like some broiled flounder with your serving of climate apocalypse?
Well, you’re going to have to broil it yourself, because record-breaking temperatures in the Atlantic Ocean are driving the fish away from fast-heating waters toward more hospitable depths and latitudes.
The Atlantic Ocean’s surface temperatures from Maine to North Carolina broke records last year, reaching an average of 57.2°F, nearly three degrees warmer than the average of the past 30 years.
That’s according to new data published by National Oceanic and Atmospheric Administration, which says the jump in average temperature from 2011 to 2012 was the largest recorded one-year spike in the marine region, which is known as the Northeast Shelf Ecosystem. Last year’s average temperature was also the highest recorded there since measurements began 150 years ago.
Here’s a graph that shows the spike:
And here’s another, showing last year’s water temperatures in red. The gray line represents average temperatures and the gray shading shows standard deviations from that average:
That’s not too shabby if you fancy a balmy dip in the brine. But the implications for the ecosystem’s wildlife and fisheries could be profound.
The production of plankton, which forms the basis of oceanic food webs, appears to have been affected. NOAA scientists discovered that fall plankton blooms were smaller than normal in the area last year, which would be making it harder for fish and other species to find food right now. And they found that the shelf’s fish and shellfish were fleeing from their normal habitats, chased north or into deeper waters by the extraordinary heat.
These abnormally high temperatures are fundamentally altering marine ecosystems, from the abundance of plankton to the movement of fish and whales. Many marine species have specific time periods for spawning, migration, and birthing based on temperature signals and availability of prey. Kevin Friedland, a scientist in NOAA’s Northeast Fisheries Science Center’s Ecosystem Assessment Program, said “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.”
Black sea bass, summer flounder, longfin squid, and butterfish were among the commonly fished species that moved northeast as the temperatures rose, NOAA says.
The record-breaking heat off the Atlantic coastline is typical of a worrisome worldwide trend. The world’s oceans are absorbing a lot of the globe’s excess heat. That’s helping keep down land temperatures in a warming world, but it threatens to throw marine ecosystems into turmoil. And scientists warn that the oceans won’t absorb so much of the extra heat forever. Eventually we’re going to broil not only the seas, but also the land.
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