Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Strategies & Market Trends : Booms, Busts, and Recoveries -- Ignore unavailable to you. Want to Upgrade?

To: Gib Bogle who wrote (61745)	4/12/2005 4:07:06 AM
From: Maurice Winn	Read Replies (3) \| Respond to of 74559

< About 3% is CO2, but only a tiny fraction of this is the result of human activities. > Hello Gib. I think about 15% of atmospheric CO2 came from human sources, so there isn't much effect if your other numbers are correct; something like 0.5%, which isn't exactly a big deal. Mq

To: Gib Bogle who wrote (61745)	4/12/2005 4:10:03 AM
From: Raymond Duray	Read Replies (2) \| Respond to of 74559

Re: It appears that variation in CO2 level probably has an undiscernible effect of global temperature. Hiroshima and Nagasaki had a nearly undiscernable effect upon WW II. Were these human caused tragedies therefore, by your logic, inconsequential? I learned today that 95% of the greenhouse gas is water vapour. Some of us know that the 15 KM envelope of gas surrounding our blue planet appears inconsequential from space. Should we therefore assume we can simply blow it off?

To: Gib Bogle who wrote (61745)	4/12/2005 7:47:09 PM
From: Moominoid	Respond to of 74559

Yes water vapor is the most important greenhouse gas and CO2's direct role is low. Without water vapor, CO2 and methane in the atmosphere the temperature would be -18 C rather than plus 15 C (assuming somehow that the amount of clouds etc was held constant without all that water). Doubling CO2 would have about a 1 C affect on average global temperatures. This is amplified by feedbacks that among other things increases the water vapor in the atmosphere (the thinking is very similar to that in macroeconomic models for those who are familiar with them). The question is how big the feedbacks are. Seems from the historic record and the climate models the multiplier could be as big as 3-4 though there is still tremendous uncertainty about that. So far people have increased CO2 from 270 ppm in the 18th century to about 380 ppm now. Without human activity in the millenia from the end of the last Ice Age till the 18th century it seems that CO2 would have been even lower than that.

To: Gib Bogle who wrote (61745)	4/12/2005 9:51:30 PM
From: Snowshoe	Read Replies (1) \| Respond to of 74559

Wikipedia says CO2 causes 9-26% of the greenhouse effect... en.wikipedia.org Greenhouse gases (GHG) are gaseous components of the atmosphere that contribute to the greenhouse effect. The major natural greenhouse gases are water vapor, which causes about 36-70% of the greenhouse effect on Earth (not including clouds); carbon dioxide, which causes between 9-26%; and ozone, which causes between 3-7% (note that is it not really possible to assert that such-and-such a gas causes a certain percentage of the GHE, because the influences of the various gases are not additive. The higher ends of the ranges quoted are for the gas alone; the lower end, for the gas counting overlaps). [1] (http://www.atmo.arizona.edu/students/courselinks/spring04/atmo451b/pdf/RadiationBudget.pdf) [2] (http://www.realclimate.org/index.php?p=142). Minor greenhouse gases include methane, nitrous oxide, sulfur hexafluoride, and chlorofluorocarbons. The major atmospheric constituents (N2 and O2) are not greenhouse gases, because homonuclear diatomic molecules (eg N2, O2, H2 ...) do not absorb in the infrared as there is no net change in the dipole moment of these molecules.