Posted on 02/23/2007 4:19:11 PM PST by blam
Warming Sign? Larger dead zones form off Oregon coast
Sid Perkins
Unprecedented recent changes in the yearly pattern of ocean currents off North America's West Coast have wreaked havoc on aquatic ecosystems there. Those changes, which have triggered the formation of large areas of oxygen-poor water along the Oregon shore, may be a troubling symptom of Earth's warming climate, a group of scientists says.
MUSSELED OUT. Poorly oxygenated waters off the coast of Oregon in the summers of 2005 and 2006 stifled the growth of sea life, such as the mussels and barnacles seen here. Lubchenco
Fisheries along the western coasts of North America, South America, and Africa account for less than 1 percent of the world's ocean area but produce more than 20 percent of its wild-caught fish. In those areas, winds that blow toward the equator at certain times of the year bring cool, nutrient-rich waters to the coastal shallows, says Jane Lubchenco, a marine biologist at Oregon State University in Corvallis. In the past few years, however, productivity of some species has decreased precipitously, she and her colleagues reported last week in San Francisco at the annual meeting of the American Association for the Advancement of Science.
For example, large areas of oxygen-poor water, often called dead zones (SN: 6/5/04, p. 360: http://www.sciencenews.org/articles/20040605/bob9.asp), now form each summer off Oregon. Such zones first appeared in 2002, but during the past 2 years, they were longer lasting than before and had lower oxygen concentrations, says Lubchenco.
John A. Barth, a physical oceanographer at Oregon State University, notes that in 2005, the annual onset of southerly winds off the Oregon coast was delayed from mid-April to mid-May. Lacking their usual input of nutrients, the plankton at the base of the region's aquatic food chain didn't thrive, and many plankton-eating creatures starved. When the winds finally kicked in, they brought an excess of nutrients that fed profuse, widespread blooms of algae that later died and decomposed, robbing the water of oxygen.
That double whammy of starvation and suffocation struck ecosystems hard, Barth reports. For instance, the number of young barnacles that he and other scientists found off the Oregon coast between June and August 2005 was 34 percent of normal. The tally of young mussels ended up at 17 percent of average in other years. Underwater cameras showed large numbers of dead Dungeness crabs in many areas.
In 2006, by contrast, southerly winds appeared earlier than normal and brought nutrient-rich waters to shore all summer long, fueling algal blooms that again devastated the ecosystem.
In the past 2 years, the breeding seasons of many seabirds along the West Coast have been disrupted, says Julia Parrish, a marine biologist at the University of Washington in Seattle. In the Farallon Islands off California, auklets abandoned their nests and produced no chicks, presumably for lack of food. "These birds were stressed out when they should have been pigging out," she noted at the meeting.
Analyses of recent wind patterns suggest that year-to-year variability in the winds off Oregon is getting stronger, says Barth. The wind changes that the scientists have noted are consistent with what's expected in response to climate change, but the specific cause of the change in wind patterns is unknown, Lubchenco says.
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Click graphic for full GW rundown
Ping me if you find one I've missed.
Remember when the environmentalists said Alaska's shoreline would be ruined when the Exxon-Valez spilled oil? The fish and wildlife thrived after the accident.
Yah, sure.
Generally, winds on the Oregon Coast are southerly in the winter swinging northwesterly after the passage of a low pressure system. In the summer, the winds are generally northwesterly due to the presence of the Pacific High. In fact, this "rule of thumb" prevails along the entire Pacific Coast of the US. In the article, Mr. Barth has the general wind pattern completely backwards. In fact, by mid May, the general wind direction is northwesterly. Strange conclusions indeed. A NOAA Weather Fax for the next 24 hours shows NW winds shifting to strong southerly winds. Go figure.
Yup...and, the Caribou heards thrived. The pregnant Caribou began to have their babies under the warm (elevated) oil pipelines and more Caribou babies survived as a consequence.
Without long term trend data these assertions are totally useless. On the east coast we have red tide which creates problems for the clam flats. These evidently have been known for eons. I would check this story out with some long time fishermen in the area - especially those who are not likely to look for a Government bail out.
I'd look at the hot underwater vents just off the coast...may be the exit flows have increased, became more toxic, hotter?
I am sure these scientists have exhausted all possible alternative causes, especially the more obvious ones, before resorting to Global Warming. /s
The more this continues the more it feels like we are returning to a society as rendered in Gibson's Apocalypto where the "scientists" (the could predict eclipses) acted as priests and used their slightly greater knowledge to control the superstitious and ignorant locals. We are seeing science being attacked by a homocentric myth akin to pre-Kepler astronomy. Fortunately it will take only a few additional solar based empirical findings to blow this nonsense out of the water. Perhaps this time we can maintain the focus on the damage done by the hysteria - most of Africa is still plagues by the banning of DDT courtesy of Rachel Carson and the failure to adequately use the scientific tools we have to control diseases.
Analyses of recent wind patterns suggest that year-to-year variability in the winds off Oregon is getting stronger, says Barth. The wind changes that the scientists have noted are consistent with what's expected in response to climate change, but the specific cause of the change in wind patterns is unknown, Lubchenco says.
Now that's hard science!
Fear..huh...What is it good for?...Absolutely Nothin'
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When they atart naming scientists and experts I might start believing these articles, until then sounds like spin.
By the way my fav other is unnamed sources buzz word for made up/untrue or facts not in evidence.
"Such zones were first appeared discovered in 2002, it's not known if they occurred naturally before then"
No... the zones were first discovered in 2002. Whether they have appeared periodically over the last 4 billion years is an open question
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