1. R. Watson, Future Files: A History of the Next 50 Years (Q. Zhang, Trans.), Jinghua Press, Beijing, 2008. p. 33.
2. X. Yang, Global Warming or Cooling? http://www.Ses303.net/yangxuexiang/13.php.
3. http://en.wikipedia.org/wiki/global_cooling.
4. In its fourth assessment report released in 2007, the IPCC states that “warming of the climate system is unequivocal” (IPCC report is the only document in which this term is used), and 90% of the chances suggest warming is caused by anthropogenic emissions of greenhouse gases into the atmosphere. https://en.wikipedia.org/wiki/IPCC_Fourth_Assessment_Report. A. Giddens, The Politics of Climate Change (R. Cao, Trans.), Social Science Academic Press, Beijing, 2009, p. 21.
5. http://www.nipccreport.org/aboutNIPCC.html.