A May 15 letter to our local weekly paper, the Independent Coast Observer of Gualala, California, referred to one of my letters and began: “A previous letter falsely stated that increased CO2 concentrations can’t initiate a warming trend.” The writer then followed this by admitting that the Vostok ice core samples proved that solar cycles initiated previous temperature increases and subsequent CO2 rise (an inconvenient truth Al Gore got backwards), “but that is not the case in our present warming trend.”
That’s false. Our current warming trend began over 400 years ago, long before atmospheric CO2 increased significantly (Moberg et al, published in Nature, Vol. 433, No. 7026, pp. 613 - 617, 10 February 2005). From the end of the Little Ice Ages, approximately 1860, until 1940, the global temperature increased about 0.6º C. From 1940 to present, it’s only increased 0.4º C, and the Globally Averaged Satellite-Based Temperature of the Lower Atmosphere from January 1979 through April 2009 has only increased 0.2º C. The past four years show a cooling trend; 2008 was the 14th coldest year of the past 30, and 2009 could be even colder.
Returning to the Vostok ice core samples, they not only proved solar intensity initiated warming and subsequent CO2 increases, but equally as important showed that increased CO2 levels do not prevent cooling. That’s right. In every instance, as CO2 remained high, cooling began, and then CO2 levels decreased as the cooling oceans absorbed it.
These facts make logical sense. CO2 is only four percent of greenhouse gases, compared to water vapor which is over 90%, and it would be foolish to attribute warming to a trace gas instead of to the extensively documented prowess of the sun. Solar fluctuations result in heating and cooling of the oceans, and the warmer or cooler oceans release or absorb CO2.
The CO2 tail can’t wag the climate change dog.