Some people will say that water vapor is the dominant greenhouse gas, but they ignore the fact that water vapor concentration is dependent on temperature. My suspicion is that the ratio of carbon dioxide to water vapor in the atmosphere is fairly constant, although other greenhouse gases, like methane, bring their own water vapor into the atmosphere.

Prior to humans burning fossil fuels, atmospheric concentration of carbon dioxide was determined by a balance between carbon dioxide released by volcanoes and absorbed by the oceans. The biological carbon cycle has little impact on climate, because it is balanced.

As a result of variations of Earth's orbit, the oceans go through cyclic changes in temperature. When they cool, they absorb extra carbon dioxide and when the warm, they release carbon dioxide. The tundra also releases methane which is oxidized to carbon dioxide. Methane is a more potent greenhouse gas than carbon dioxide, which is wh carbon dioxide increases for centuries after the temperature starts to decline.

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And Pat responds to Prico's link with an ad hom.

Skeptical =/= denialist

It doesn't.

There has been no proof that it does. Mostly everyone sees this as a fact. Even Al Gore's carbon trading scheme went bellies up due to people finding out it was a scam. But there are a few die hard greenies who won't succumb to the truth.

Prico: In case you haven't kept up with the latest science, the Earth has been cooling for over a decade now. Even Phil Jones and James Hansen have had to admit this. Yet, at the same time the CO2 level has risen. These two facts are indisputable. So it is a scientific conclusion that CO2 doesn't control the temperature. If you would quit getting your science from Sesame Street, Bill Nye (The science lie), Wikipedia, and Skepticalscience you might learn something. If you wish I can fix you up with some credible sources, ones by real scientists not propagandists.

Carbon cycle regulate the climate on earth for reaching temperature and making Ecological imbalance.

It doesn't except in the mind of a deluded alarmist. Recent climate (Quaternary) is regulated primarily by the Milankovitch cycles based on the vast majority of scientific opinion. At most, CO2 is a bit player. Other carbon compounds are even less important. .

http://climateclash.com/the-limits-of-ca...

"The 820 petagrams is 0.0164 percent of the total weight of the atmosphere (2), which converts to 394 ppm CO2 closely matching the current Mauna Loa measurement of 393 ppm (Figure 3) Figure 1 shows an atmospheric CO2 exchange rate with the land and ocean of 200 petagrams per year. The time to replenish is the ratio of its content to the exchange rate, or 820/200 = 4.1 years. This is the average retention time for a molecule of atmospheric CO2."

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Humans have very little impact on it. The carbon cycle is why we are living. Carbon is a very important aspect of life itself. The small percentage that humans emit into the atmosphere is hurting nothing and (in fact) only helps all life on the planet. The planet has been warming since the mid 1600s (after the last major cooling period). Global Warming advocates have been riding a warming period on our planet and have attached the increase of CO2 emissions to the current warming period. They say humans are causing the planet to warm. Nothing could be farther from the truth.

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Prico - SkepticalScience.com is a biased blog site. Always has been. There's nothing skeptical about it. You're a broken record that repeats the same information over and over again. Educate yourself and learn something new. You're boring!