30 October 2015

Wow! Moment as Scientists Discover What’s Really Decimating The Cod Fishery

Posted by Dan Satterfield

Look how warm the ocean is over the Northeast U.S. and Maritime Canada. Image from WX Bell.

Look how warm the ocean is over the Northeast U.S. and Maritime Canada. Image from WX Bell.

No doubt that overfishing has decimated the Cod fishery, but the extreme restrictions put on the Cod catch has done little or no good, and the numbers are now down to 3-4% of a sustainable fishery. Apparently, what was really happening has been staring us in the face for over a decade, and it’s not good news. To put it in science denier terms- “It’s the warming oceans stupid!”

A major paper in Science today (free to read here) shows just what has been happening. Here is the abstract:

Several studies have documented fish populations changing in response to long-term warming. Over the last decade, sea surface temperatures in the Gulf of Maine increased faster than 99% of the global ocean. The warming, which was related to a northward shift in the Gulf Stream and to changes in the Atlantic Multidecadal and Pacific Decadal Oscillations, led to reduced recruitment and increased mortality in the region’s Atlantic cod (Gadus morhua) stock. Failure to recognize the impact of warming on cod contributed to overfishing. Recovery of this fishery depends on sound management, but the size of the stock depends on future temperature conditions. The experience in the Gulf of Maine highlights the need to incorporate environmental factors into resource management.

Look at the rate of warming in the oceans (from the paper in Science today).

The waters of the Gulf of Maine are warming faster than 99% of the rest of the oceans.

The waters of the Gulf of Maine are warming faster than 99% of the rest of the oceans.

This paper comes out the same week that the fall “king tides” caused significant flooding issues from Miami to New England. Here on the Eastern Shore of Maryland, we are dealing with flooding issues that seem to be getting worse each year, and the data clearly explains why. I showed the graphics below on air tonight, and as I type this, the residence of Oak Orchard, Delaware are meeting with state officials to beg for drainage improvements, after serious flooding from the king tides.


12189734_10153308291421359_4813519275139880971_nLook at the data above from Norfolk. The waters around the Chesapeake Bay are up about 1.5 to 2 inches since the beginning of THIS century, and this is showing up during the high astronomical tides (and during coastal storms). I did not include any North Carolina data since the legislature there outlawed sea level rise, but apparently they didn’t outlaw warming waters. NOAA published a good report on this nuisance flooding last year and it’s worth a read.

The image below is from the NOAA report:

Screen Shot 2015-10-29 at 9.19.30 PM

Two things I have noticed. The Barents Sea is also warming at a very fast rate and the ice cover there is well below average for late October. Meteorologist Judah Cohen has data that seems to link low ice levels there to a more frequent negative Arctic Oscillation pattern. The negative AO events tend to bring cold and snowy winter weather to the East Coast. The second thing to note is that those low-pressure nor’easters that develop in negative AO events, will have a lot of warm moist air to feed on, as they move over the warm ocean off the Mid-Atlantic and New England coastline.

Well, that’s worth thinking more about!

In his now classic paper  from 1981, James Hansen said  “It is shown that the anthropogenic carbon dioxide warming should emerge from the noise level of natural climate variability by the end of the century, and there is a high probability of warming in the 1980’s.” In other words, people will start to notice something is different in the first part of the 21st century.

He sure got that right.