David King, the chief scientist for Tony Blair, former Prime Minister of Britain wrote in the British Science magazine, 9 January 2004, “Climate change is real, and the causal link to increased greenhouse emissions is now well established.” (“Climate Change Science: Adapt, Mitigate, or Ignore?” Science 9 January 2004: Vol. 303. no. 5655, pp. 176 – 177)
Blair’s government then commissioned Sir Nicholas Stern, a former chief economist from the World Bank, to produce a 700 page study, after which Stern suggested that global warming could shrink the global economy by 20%. (BBC news, 30 October, 2006).
The United Nations has an Intergovernmental Panel on Climate Change which is continually producing very detailed, thoroughly researched documents.
As an indication of their findings and mood of the IPCC, over 200 such scientists at a conference in Bali in 2007 warned that “many ecosystems, plants and animal species in serious danger of extinction” unless “immediate action” was taken to cut greenhouse gasses (ScienceDaily).
And more recently, February 2009, a top IPCC Scientist warns “”Without decisive action, global warming in the 21st century is likely to accelerate at a much faster pace and cause more environmental damage than predicted” (Climate Change Likely To Be More Devastating Than Experts Predicted, ScienceDaily Feb. 15, 2009).