A new study reveals the extent of the "desert of the sea," shown here in black,
where plant life is the lowest. This image is an average of ocean chlorophyll
over the study's nine-year period. NOAA
Posted on 03/22/2008 9:59:57 AM PDT by ricks_place
The region of the ocean known as "the desert of the sea" has expanded dramatically over the past decade, according to a new study. Scientists looking at the color of the ocean from space have found that vast areas that were once green with plankton have been turning blue, as marine life becomes scarcer. If it's linked to global warming, as they suspect, this could be another blow for the world's fisheries.
Just as plants make up the base of the food web on land, tiny green phytoplankton in the ocean are a critical foodstuff for life in the oceans. And Jeff Polovina, at a National Marine Fisheries Service lab in Hawaii, has been watching by satellite as that greenery in the middle of the ocean is fading away.
"The regions that are showing the lowest amount of plant life, which [are] sometimes referred to as the biological deserts of the ocean, are growing at roughly 1 to 4 percent per year," Polovina says.
One to 4 percent may not sound like all that much, but these regions are huge to begin with. So this marine desert has grown by 2.5 million square miles in the past decade. That's an area the size of Texas every year. Polovina makes the analogy to deserts on land, creeping into more productive environments.
"We have the same thing here," he says. "These less productive areas are replacing the slightly more productive areas of the ocean."
Link to Global Warming
And it seems to be tied to global warming. Polovina's study, published in Geophysical Research Letters, finds that the areas of low productivity are expanding in lockstep with increasing water temperatures. As surface temperatures warm, that prevents colder water from rising up from the depths. And that colder water carries the nutrients that would feed the algae.
Scientists studying climate change have predicted this kind of change. But the sea desert has been spreading 10 times faster than climate scientists predicted. So Polovina is a bit cautious — this could be a shorter-term fluctuation, not a permanent change.
"In the next 10 years, maybe it could switch back," he says. "Until we get a much longer time series, we don't know."
Long-Term Outlook
Whatever the case, the speed of change in the ocean is disturbing to marine scientists like Paul Falkowski at Rutgers University.
"It is amazingly fast if true," Falkowski says.
He says marine scientists using more primitive instruments from ships saw this trend starting long ago, back in the early days of the Industrial Revolution.
"We can see that over 100 years, the ocean has gotten clearer and clearer in the center," Falkowski explains. "So this is a long-term trend."
He, too, isn't sure that the trend will keep up at its current speed. But the long-term outlook is unsettling. He says the South Pacific Ocean is currently the clearest and least productive region of the Earth's oceans.
"If we made the entire world's oceans like that, we'd probably reduce the productivity by at least a factor of two. And that would be an extraordinarily large change, which I don't want to think about," Falkowski says.
Fisheries, which are already under heavy stress from nets and lines, would suffer even more, he says. Reefs would suffer, too. In all, the outlook for the oceans is bleak.
And we may not be fully aware of the situation as it changes. The satellite that made these critical measurements is nearing the end of its lifespan, and there is no full replacement in the works. So, in a few years, U.S. scientists may not be able to look at the color of the ocean from space to track this trend.
A new study reveals the extent of the "desert of the sea," shown here in black,
where plant life is the lowest. This image is an average of ocean chlorophyll
over the study's nine-year period. NOAA
...On March 19, NPR broadcasts The Mystery of Global Warming's Missing Heat. NPR informs the public that the Oceans are not warming but cooling.
So the real mystery is the lack of intelligence at NPR.
Dead Zone is another enviro buzzword that got some play a couple weeks ago. They need everything in their old pollution toolchest to replace Global Warming since that horse died.
There is no mystery about the lack of intelligence at NPR. Their radio hosts are actually androids who repeat whatever TPF (Talking Point File) that is fed into them. At present, Algore is responsible for creating the TPFs related to the environment.
You could knock me over with a feather.
Dead Zone is a good name for National PUBIC Radio.
This has all happened since the "Save the Whales" movement, and I know why. Whales eat like Americans, and consume more calories than they really need. They're killing off the plankton with their greed. That, and they tend to vote Republican. I say we start hunting them again to reduce their numbers, before we end up with McCain for President because of this voting bloc.
/insane liberal enviro rant (note - I might have actually been able to post this at DU and get away with it, mostly by blaming the whales for being Republicans).
Hey igit, the oceans have been cooling for the past couple of years.
My daughter is a geologist. Degree in HydroGeology. She said that the Sahara Desert used to be ocean bottom. I think the earth is a dynamic creation, always changing. Volcanoes, hurricanes, earthquakes, continental plate shift, etc.
My marine biology professor lectured us on so called ‘dead zones’ years ago - found in warmer climes, higher salt content means lower plankton, and clearer, bluer water. Common sense would dictate these zones would fluctuate in size, like the ozone hole or ice shields.
Well, glory be. I think we’ve just found the answer to our landfill problem.
I just sent your comment to NPR’s two news emails and story submission email.
BTT
Guess: the middle ocean is nutrient depleted. The GW movement will propose sending land runoff to the deadzone next!
Yea, most of us learned that in the 3rd grade.
“Link to Global Warming”
NPR = National Carbon Credit Radio, again and again
Not runoff, but iron of all things.
Experiments have proven this to be a valid fix
http://en.wikipedia.org/wiki/Iron_fertilization
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