The earth's climate ended its last warming phase in 1998 and, even though our carbon emissions have increased, the warming climate has since entered a “pause” and has even begun to cool. It should now be apparent that mankind has not had a material affect on the climate and the following reasons explain why:
1. The so-called greenhouse gases are all natural materials and have existed at much higher levels in the past when primitive man had much lower levels of emission (even Neanderthals produced carbon dioxide, a greenhouse gas, by breathing).
2. Of all the greenhouse gases water vapor is by far the most prevalent, comprising about 95% of all greenhouse gases in the atmosphere. The remaining gases, including the much-maligned carbon dioxide, are considered trace gases and are too insufficient to impact our climate.
3. When gases, including the greenhouse gases, absorb heat they rise into the atmosphere by convection. The same way that the warmest water boiling in a sauce pan rises to the top. As the gases rise, they give off their warmth and therefore reduce the impact on the earth's climate. The exception to this is water vapor that precipitates into liquid water as it cools and eventually falls back to earth as rain. The rain still has some of its absorbed heat and therefore, by returning to the earth, has the effect of keeping the earth warm. Carbon dioxide continues to rise and lose its heat. Water vapor is the only effective greenhouse gas.
4. Carbon dioxide is not a form of pollution but, in fact, helps green plants to grow. Increased carbon dioxide means that plant life need less water to grow and farmers and ranchers have better crops and fatter cattle. Carbon dioxide is an essential part of all life on earth.
5. Very little of the carbon dioxide in our atmosphere is produced by mankind and our industries. The ocean is the primary source and sink of carbon dioxide and oxygen. The plant life in the ocean absorb carbon dioxide that exists in the water just as the fish breath oxygen that is trapped in the ocean. The oceans absorb twenty times as much carbon dioxide as mankind produces.
6. Even if mankind produces a little carbon dioxide, the greater the amount of carbon dioxide in the atmosphere, the greater the amount that is absorbed by the oceans. This is known as Henry's Law of gas absorption.
7. Why then does the level of carbon dioxide in the atmosphere increase and decrease? Because the sun's radiation changes through cycles of heavier and lower sunspot activity. When the activity is high, the climate of the earth warms and eventually causes the oceans to warm. As any fisherman/woman knows, warm water holds less oxygen and carbon dioxide than cooler water. This makes cold water better for fishing, since it contains more trapped gases and therefore more plant life and more fish. This is the second part of Henry's Law. Carbon dioxide does not cause global warming, but rather, global warming, caused by the sun, causes the oceans to absorb less carbon dioxide, leaving more in the atmosphere.
In summary, our climate has been much hotter in the past, before our modern industrialization, because the sun has occasionally been more violent and has caused more climate warming. In turn, this periodic global warming has caused atmospheric carbon dioxide to increase. Climate change causes increased atmospheric carbon dioxide rather than carbon dioxide causing global warming.
— Robert Meldahl, Hamilton