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Politics : Formerly About Advanced Micro Devices -- Ignore unavailable to you. Want to Upgrade?

To: J_F_Shepard who wrote (740128)	9/17/2013 10:11:11 PM
From: TimF	Read Replies (1) \| Respond to of 1574772

I understand how greenhouse gases work and than CO2 is one. Those facts don't get you "Severe and unusual climate change almost totally caused by CO2 emitted from human activity that will cause an extreme disaster (many cities, and areas such as almost the entire state of FL) to be flooded and perhaps cause a mass extension event, within a generation or two or at most a century, if we don't cut CO2 emissions by something like 75 to 99% (depending on the specific claim) within (again depending on the specific claim) 1 to 20 years."

To: J_F_Shepard who wrote (740128)	9/18/2013 7:53:33 AM
From: Brumar89	2 Recommendations Recommended By Taro TideGlider Read Replies (1) \| Respond to of 1574772

CO2 is a small part of normal air. And CO2 is measured in parts per million and is REQUIRED for life to exist on earth. Fact is, geological processes have been removing CO2 from the atmosphere and tying it up in things like limestone, coral, fossil fuels, etc for hundreds of millions of years and during the last ice age plants were experiencing carbon starvation: Carbon starvation in glacial trees recovered from the La Brea tar pits, southern California Pertenece a: PubMed Central (PMC) PubMed Central (PMC3 - NLM DTD) Descripción: The Rancho La Brea tar pit fossil collection includes Juniperus (C3) wood specimens that 14C date between 7.7 and 55 thousand years (kyr) B.P., providing a constrained record of plant response for southern California during the last glacial period. Atmospheric CO2 concentration ([CO2]) ranged between 180 and 220 ppm during glacial periods, rose to ?280 ppm before the industrial period, and is currently approaching 380 ppmin the modern atmosphere. Here we report on ?13C of Juniperus wood cellulose, and show that glacial and modern trees were operating at similar leaf-intercellular [CO2](ci)/atmospheric [CO2](ca) values. As a result, glacial trees were operating at ci values much closer to the CO2-compensation point for C3 photosynthesis than modern trees, indicating that glacial trees were undergoing carbon starvation. In addition, we modeled relative humidity by using ?18O of cellulose from the same Juniperus specimens and found that glacial humidity was ?10% higher than that in modern times, indicating that differences in vapor-pressure deficits did not impose additional constrictions on ci/ca in the past. By scaling ancient ci values to plant growth by using modern relationships, we found evidence that C3 primary productivity was greatly diminished in southern California during the last glacial period. biblioteca.universia.net We probably can't prevent another ice age. The last 2 million years have seen recurring ice ages separated by relatively brief interglacial periods like the current one in which human civilization has arisen. Much of the inhabited surface of the earth will be covered by ice sheets or will be converted into tundra. The rest of the earth will extraordinarily arid. At least plant life won't be undergoing carbon starvation though.