Feb 13, 2010

Coastal current chaos coming if wind industry sets up in Gulf of Maine

In Homeric myth the priest Laocoön warns the Trojans against accepting the wooden horse presented them by the suddenly cheerily departing Greeks. Serious FAIL ensues when he is disregarded.

Likewise, Maine fishermen - beleaguered already by a host of corporate and governmental enemies - now find themselves being courted by big energy companies and their hangers-on  consider windmills a sort of "gift" from them. bringing new vertical habitat to marine life to cluster, and causing upwellings, where nutrient-richer seafloor water is pulled to the surface by the energy differential at the surface below where the energy is being extracted frmo the natural environment

But canny fishermen are increasingly wary of the potential for offshore windfarms to put a lasting crimp in Maine's lobster fishery, for these artificial upwellings can wreak havoc by fomenting current-diverting "chaotic excursions" at the interface where the normal lively surface waters of the Gulf of Maine meet the "harmonized" low-energy surface waters that make up  the aquatic 'half-dead zones' found downwind of ocean wind turbine fields.

What could be taking an excursion are the surface currents transporting lobster larvae and other zooplankton down the Gulf of Maine coast from Lubec to well beyond Cape Anne.The so-called "coastal current chaos" may divert larvae-bearing currents AWAY from the coast.

These predictions - and similar dire warnings for the Chesapeake Bay's famed blue crabs - come from an analysis of the results of  the study "Chaotic behavior of coastal currents due to random wind forcing"  by researchers at the National Institute of Standards & Technology in Gaithersburg Maryland, as well as other reports mentioned below.  Those results suggest the possibility that  persistent reduced-energy zone "footprints" could appear downwind of energy-extracting offshore wind removal operations, with implications for current flows. 

Normally, prevailing strong oceanic  winds keep coastal currents close inshore for much of of the Gulf of Maine.  But, diverted even slightly off course by the clash between upwelling  'harmonized' waters surrounding  proposed Gulf of Maine offshore windfarms,  and the normal  Maine Coastal Current, portions of that current may veer offshore many miles prematurely, to expend itself and its luckless planktonic passengers in the deep Wilkinson Basin.  There, a lobster larvae's typical fate is to become prey for the basin's native species.  

But don't worry, the government, the industry and the eco-yuppies are working out "community benefit agreements" in which lobstermen will be paid off for their wandering resource.  The lobster buyers, marketers and retailers, alas, will just have to find new work.

The lobsters, too, will have to fend for themselves.

UPDATE:  Offshore wind power could alter ocean currents This report by the Norwegian Meteorological Institute's Goran Brostrom concurs with the earlier NIST study. 
 "Extracting energy from wind changes regional air currents, which can in turn affect how the nearby ocean circulates", Brostrom told MSNBC. "Generating wind power at sea may disturb ocean currents and marine ecosystems."

Indeed, the upwellings Profesor Brostrom describes as resulting from the removal of energy from  a comparatively small but intensively harmonized  sea surface area in and around a windfarm of the types proposed for the Gulf of Maine are the very chaotic excursions described in the National Institute of Standards study, cited above.


micronaut said...


Intrigued by your references to the Brostrom and Simiu papers, I downloaded and read them both. The NIST report, "Chaotic Behavior of Coastal Currents Due to Random Wind Forcing," is a purely mathematical exercise in modeling chaotic behavior using the author's special toolbox -- the Melnikov Process.

The obscure NIST paper, published sixteen years ago, has been cited by very few, including Dr. Brostrom despite your implication that he does. The author's reference to "harmonics" (simply a mathematical construct so he could pose his equations) was given a fanciful roller coaster ride by you. The NIST paper doesn't mention wind farms or wind turbines, or "dire warnings" let even blue crabs.

The other paper published in 2008 by Dr. Brostrom, while also highly theoretical, is in the main stream of physical oceanography. He makes a case that under certain very specific conditions, the wind deficit behind a wind farm could generate or perturb existing upwelling. I would hope that oceanographers familiar with the Gulf of Maine would evaluate the possibility of wind farm induced up-and-down-welling. It's worth a look at, but my gut tells me that it would be negligible.

Jim Mays, Rockport

Ron Huber said...

Obscurity has no necessary bearing on validity.