September 17, 2000 SEARCH Collecting Core Samples Earth Shrugged off Ancient Warming By Mari N. Jensen, Discovery.com News Sept. 13, 2000 -- When the sea floor burped a big cloud of greenhouse gases 55 million years ago, the ocean's plankton responded with a burst of growth that sucked the gases out of the atmosphere, researchers report in this week's issue of the journal Nature. Earth, which had been warming, returned to its pre-burp temperature. Scientists had proposed that the biosphere has such a self- correcting mechanism, but this is the first evidence that such corrections have actually happened. "A case of global warming that has some similarities with our present condition has the prospect of being turned off just by jacking up the production by phytoplankton. Wow, I think that's really great," said study co-author Richard Norris, a paleobiologist at the Woods Hole Oceanographic Institution in Mass. Scientists already knew there had been an intense period of global warming about 55 million years ago. The warming coincided with a series of releases of frozen greenhouse gases from the ocean floor. The atmospheric build-up of greenhouse gases, like carbon dioxide, may warm the planet by trapping heat from the sun. To figure out what subsequently cooled the earth, a team of researchers examined sediment cores taken from the ocean floor in the Caribbean and off the coasts of Florida, Antarctica and Africa. The team measured the quantities of a mineral called barite - - an indicator of the plankton productivity in the oceans. In the cores, levels of barite jumped at the same time the earth's temperature and greenhouse gas concentrations started to increase. And a drop in barite levels coincided with a reduction in these factors. Those changes in barite levels imply that under the favorable conditions of high temperature and atmospheric carbon dioxide, life in the oceans bloomed, says lead author Santo Bains, a paleoclimatologist at the University of Oxford in England. Plankton, like plants, rely on carbon dioxide to grow. The phytoplankton bloom in the oceans then "occurred on such a large scale that it effectively removed all the carbon dioxide from the atmosphere," and the earth cooled. Steven D'Hondt, a geobiologist at the University of Rhode Island in Narragansett, says, "It's nice evidence that this hypothetical feedback really operated at that time." In terms of global warming, he says, "It tells us if we do nothing and wait around for 60,000 years, the ocean will take care of it for us." -- Kathleen One of the most striking differences between a cat and a lie is that a cat has only nine lives. --Mark Twain <A HREF="http://www.ctrl.org/">www.ctrl.org</A> DECLARATION & DISCLAIMER ========== CTRL is a discussion & informational exchange list. Proselytizing propagandic screeds are unwelcomed. Substance—not soap-boxing—please! These are sordid matters and 'conspiracy theory'—with its many half-truths, mis- directions and outright frauds—is used politically by different groups with major and minor effects spread throughout the spectrum of time and thought. That being said, CTRLgives no endorsement to the validity of posts, and always suggests to readers; be wary of what you read. CTRL gives no credence to Holocaust denial and nazi's need not apply. Let us please be civil and as always, Caveat Lector. ======================================================================== Archives Available at: http://peach.ease.lsoft.com/archives/ctrl.html <A HREF="http://peach.ease.lsoft.com/archives/ctrl.html">Archives of [EMAIL PROTECTED]</A> http:[EMAIL PROTECTED]/ <A HREF="http:[EMAIL PROTECTED]/">ctrl</A> ======================================================================== To subscribe to Conspiracy Theory Research List[CTRL] send email: SUBSCRIBE CTRL [to:] [EMAIL PROTECTED] To UNsubscribe to Conspiracy Theory Research List[CTRL] send email: SIGNOFF CTRL [to:] [EMAIL PROTECTED] Om
