Twentieth Century warming was nothing unusual. Climate is cyclic, and there are cycles within cycles. The graph below, based on reconstruction from the geologic record, shows that there have been several cycles of warming and cooling since the end of the last glacial epoch. The temperature during the Holocene Climate Optimum was 3ºF to 10ºF warmer than today in many areas.

 Evidence for these cycles is found in the ice cores from Greenland and Antarctica, in fossil pollen records, in cores of sediments taken beneath lakes and the ocean, in the distribution of glacial deposits, in the analysis of stalagmites in caves, and in the historic record. These records also show that the cycles were global events.

It is still unclear why these cycles occur at the intervals they do. Some researchers say it’s a combination of solar cycles which periodically reinforce each other both positively and negatively.

For most of the history of this planet, atmospheric carbon dioxide levels were more than 10 times the current level. For most of the last 250 million years carbon dioxide levels were more than three times the current level.

Climate alarmist claims that our carbon dioxide emissions could trigger runaway global warming is pure nonsense. It if could happen, it would have happened already. Run-away warming cannot happen on this planet because Earth is a water world. Warming increases evaporation. Water vapor, and its latent heat, is carried aloft by convection. Heat is lost to space when the water vapor condenses. The condensation also produces clouds which reflect incoming solar radiation. That is Earth’s negative feedback mechanism to prevent run-away warming.

Sources:

Dansgaard, W. , et al., 1969, One Thousand Centuries of Climatic Record from Camp Century on the Greenland Ice Sheet, Science 17 Vol. 166. no. 3903.

Friis-Christensen, E. And Lassen, K., 1999, Length of Solar Cycle: An Indicator of Solar Activity Closely Associated with Climate, Science 254.

Hu, F.S. et al., 2003, cyclic Variation and Solar Forcing of Holocene Climate in the Alaskan Subarctic, Science 301.

Niggerman, S., et al., 2003, A Paleoclimate Record of the last 17,000 Years in Stalagmits from the B7 Cave, Sauerland, Germany, Quaternary Science Reviews 22.

Pisias, N.G. et al., 1973, Spectral analysis of Late Pleistocene-Holocene Sediments, Quaternary Research, March 1973.

Schönwiese, Christian, 1995, Klimaänderungenaten, Analysen, Prognosen.-224 S.ISBN: 978-3-540-59096-5.

Viau, A.E. et al., 2002, Widespread Evidence of 1,500-yr Climate Variability in North America during the Past 14,000 Years, Geology 30.

We have all heard scary scenarios about global warming. We therefore propose to limit our carbon dioxide emissions, assuming that they are responsible for the warming. So, the central question is: How much carbon dioxide does it take to theoretically raise global temperatures by 1 degree C ?

That number can be gleaned from global emissions reports and IPCC scenarios.

Based on data from the Carbon Dioxide Information Analysis Center (DOE) we see that it takes about 15,700 million metric tonnes (mmt) of CO₂ to raise atmospheric concentration by 1 part per million by volume (ppmv).

In 2000, mean atmospheric CO₂ concentration was 368 ppmv (NOAA global index).

The “let’s do nothing” scenario of the IPCC Fourth Assessment Report (2007) predicts CO₂ concentration will rise to 836 ppmv by 2100– a 468 ppmv rise. In the same scenario, the IPCC predicts a temperature rise of 3.4 degrees C. Therefore, under that assumption, to get a 1 degree C temperature rise requires a 140 ppmv rise in atmospheric CO₂ concentration (468/3.4 140).

So, simple arithmetic shows that to get a 1 degree C temperature rise requires carbon dioxide emissions of 2,198,000 mmt. (15,700 mmt/ppmv x 140 ppmv/ C = 2,198,000 mmt of CO₂ ). That’s 2 million million tonnes of CO₂.

According to the EPA, total human CO₂ emissions in the U.S., from all sources, including power plants, industry, automobiles etc. were 6,103 million metric tonnes in 2007. If we stopped all U.S. emissions it could theoretically prevent a temperature rise of 0.003 C. (6,103/2,000,000 = 0.003 C.)

You can do your part; just stop driving your car. The average family car puts out 5.5 tons of CO₂ annually and is theoretically responsible for a temperature rise of 0.00000000000311ºC, three one-hundred-billionths of a degree. You can be so proud.

The calculation above ignores the fact that 98.5% of all carbon dioxide emissions are reabsorbed. http://www.eia.doe.gov/oiaf/1605/archive/gg04rpt/pdf/tbl3.pdf So that actual emissions would have to be 146 million million tonnes to get a 1 C temperature rise, i.e., if we stopped all U.S. emissions it would really prevent a temperature rise of just 0.00004 C. But it will take even more than that because the effect of CO₂ concentration is logarithmic, not linear as assumed above.

Now do you see how stupid Cap & Trades schemes are? Why are we proposing to spend billions or even trillions of dollars on a temperature change we can’t even measure?

Bottom Line:

Human carbon dioxide emissions do not produce a significant change in temperature. We should not be wasting resources trying to control them. If you think differently, then provide some physical evidence to the contrary. IPCC climate models don’t count because they are just speculative computer games.