LOL!
KOMO radio 1000 (Seattle)- about a half hour ago -- Mr Ward from UW says life on planet died
so many million years ago not from a giant meteor but
by GLOBAL WARMING....
damn capitalists.
goes on and says the earth opened up and volcanic activity
created warming, but was asked the certainty of that study
and said there was another in Science published that suggested
that release of an acid gas killed -- duh? couldn't think of that one!!!!
oh yeah the rate of change in warming is the same as NOW--
oh my!
so my point..... he is complaining that he is getting emails
because it was released for the Bush inaugural.....
what is interesting is that this is an old story--
interesting but politically set up for this...IMHO--- here just in case it disappears....
see the date on this link and that Science is going to report
on this........but why wait till now?
wildmug.org
Copyright © 1997 The Seattle Times Company
Thursday, Nov. 13, 1997
Extinctions tied to global warming
by Diedtra Henderson
Seattle Times science writer
The heavy price tag for global warming: 90 percent of marine life, two-thirds of plant life and many land animals - all extinct.
This could be a thoroughly modern scenario. Scientists say it actually took place eons ago.
Examining fossils in South Africa, University of Washington paleontologists found that ancient plant-eating reptiles became extinct 250 million years ago during the same relatively short time period as much of marine and plant life. The extinctions occurred at the end of what's called the Permian Period.
The scientists conclude that heavy concentrations of carbon dioxide in the atmosphere, a greenhouse effect, so altered global conditions that many species did not survive.
The findings, announced at a recent Geological Society of America conference, have drawn widespread interest.
A British film crew was so intrigued that it immediately flew to Seattle to film UW paleontologist Peter Ward talking about the significance of the fossilized remains of extinct barrel-shaped, piglike reptiles. The journal Science is planning its own story. National Geographic scooped them all, sending a photographer to the South African dig while the fossils were excavated.
Most of the fossils remain in South Africa, but skulls and tusks from the mammal-like Lystrosaurus are tucked in Ward's cramped offices in the UW's Johnson Hall.
Research to determine what caused such wholesale loss of life so long ago continues around the globe. And if the global-warming explanation that's most popular holds water, the mass extinctions hint of the high stakes at hand when world leaders meet next month in Kyoto, Japan, to consider reductions in greenhouse-gas emissions.
"Ninety percent is a very sobering figure," Ward said.
The reference was to the amount of marine life - corals, sea lilies, reefs - that died during the mass extinction of the Permian Period, the worst in history. Thirty percent of insects disappeared, the first time the nearly indestructible creatures did not crawl away from a disaster mostly intact.
Trees on the solitary massive land mass of the time, Pangea, were wiped out. (Continents didn't break up and drift apart until years later.) The die-out led to a "feeding frenzy" among wood-rotting fungi, whose remains are preserved in sediments on five continents. And 97 percent of leaf species in southeastern Australia went extinct.
Researchers around the world have worked on this issue, with papers from scientists at the University of Oregon, Utrecht University in the Netherlands, England's University of Leeds and the Smithsonian Institution advancing various theories.
Ward's findings support past research that blames rapid changes in chemistry in the ocean for wiping out marine life and leading, by chain reaction, to extinctions on land.
Volcanic eruptions in what's now Siberia burped molten basalt onto the land and unleashed carbon dioxide into the atmosphere, warming the globe. Dying organisms filled warm, stagnant ocean waters, further depleting the oxygen supply and flooding oceans with carbon dioxide, a byproduct of decay.
Ocean levels of the tasteless, odorless carbon dioxide soared to 30 times more than current concentrations. A belch of it rose from the ocean and slowly mixed with the atmosphere.
The carbon-dioxide layer that rose and stagnated 20 miles up allowed sunlight through but trapped heat below, further slicing temperature differences between the poles and the equator.
In the South Africa dig, Ward started at the bottom of a stand of sedimentary rock exposed by a road cut and worked his way up layer by layer. He sent skulls and tusks to the University of California, Santa Cruz, to determine the concentrations of carbon 12 and carbon 13 isotopes.
The ratio of one isotope to the other changed as the Permian extinction played out. The larger the carbon spike, the worse things were for land reptiles. Also of interest was the condition of the rock. The greenish rock beds flushed red in certain layers, indicating hot, desert-like conditions, Ward said.
"This place, back then, was almost a South Pole. There's no way in the world the South Pole can be hot - except it turns very hot," he said.
Massive concentrations of carbon dioxide released from the oceans would have bumped up temperatures around the world by 4 to 6 degrees Celsius. Vertebrates don't reproduce well at those warmer temperatures; sperm fails to fertilize eggs, Ward said.
He and Ken MacLeod, a UW geological sciences post-doctoral student, looked at the concentrations of stable carbon isotopes in the Lystrosaurus fossils, finding no changes in the past 5 million years of the Permian period. Continuing their work upward in the site, the researchers found that period of stability was followed by rapid changes in the form of abundant carbon isotopes.
Similar changes in carbon-isotope concentrations were found at similar times for marine extinctions and coastal coal swamps - very different environments separated by large distances.
"This result, in turn, argues for a rapid, global catastrophe rather than some deterioration of conditions that exceeded the tolerance of different organisms for different reasons at different times in different places," MacLeod said.
Extinctions `pinpointed'
MacLeod and Ward argue that the extinctions took place in from 10,000 to fewer than a million years - about the time needed to lay down the rock that shows evidence of the changes in carbon-isotope ratios.
"They really tied down the (fact that) vertebrates disappeared about the same point," said Doug Erwin, a research paleobiologist with the Smithsonian's National Museum of Natural History. "It's a good, solid connection there."
Richard Bambach, a Virginia Tech professor of paleontology who, with other researchers, theorizes that a release of pent-up carbon dioxide caused marine extinctions, said Ward's work strengthens his research.
"They're seeing a very sharp change from a humid climate and fairly cool one to a hot climate in which the sediments get oxidized and they turn red," Bambach said. "This would be quite compatible with the idea there had been a lot of carbon dioxide released from the oceans."
But Erwin does quibble with the timing of the extinction. The best date, he says, comes from marine beds in China, which indicate the widespread extinctions occurred over 600,000 years. Erwin and a co-investigator from Massachusetts Institute of Technology will travel to South Africa in June to try to pinpoint a more exact extinction rate there.
Regardless whether zeros get added to or subtracted from the extinction rate, scientists say what remains important is the notion that current human activity may be laying the groundwork for catastrophes.
"The time scale on which it works is not overnight, or in a week, or in a year. It's centuries to a few thousand years," Bambach said. "But, you know, Shakespeare was writing plays 500 years ago. In that length of time - if we aren't careful with greenhouse gases - we could be creating the same sort of problem."
Diedtra Henderson's phone message number is 206-464-8259. Her e-mail address is: dhen-new@seatimes.com
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