(Editor’s Note: Earthjustice attorney Martin Wagner is blogging live from the Copenhagen climate change conference, Dec. 7-18. This is his first post)

The Copenhagen climate negotiations kicked off today. This gathering of the world’s governments is a crucial step in efforts to seal a deal to limit greenhouse gas emissions and fight global warming. Unfortunately, opponents of a serious agreement have dusted off long-debunked arguments about the scientific basis for global warming in a desperate effort to derail the negotiations.

Saudi Arabia, for example, made these false claims the centerpiece of its opening statement at the Copenhagen meeting. The Saudi representative pointed to e-mails stolen from a computer server used by British and American climate scientists as a basis for delaying the negotiations. According to the Saudis, these e-mails call into doubt the relationship between human activity and global warming, and undermine the need to negotiate at all.

Except they don’t.

It is ironic that the Saudi claim comes on the same day that the U.S. government, itself a climate denier for most of the years of the second Bush administration, has issued an official finding that the full body of scientific evidence "compellingly" supports the conclusion that emissions of carbon dioxide and other greenhouse gases endanger public health and welfare.

Bob Watson, former chair of the Intergovernmental Panel on Climate Change (IPCC), addressed the question of the hacked e-mails last week. According to Watson, "to suggest that this undermines the whole body of scientific evidence of human-induced climate change, and that any talk of carbon emissions cuts should be suspended, is simply untenable." Watson continues:

The global temperature analysis is robust and the work of the UEA Climatic Research Unit, on the land component, is fully supported by two separate independent analyses in the U.S. at Nasa and Noaa. The evidence for climate change over the past 100 years also comes from observed changes in retreating glaciers throughout most of the world, a decline in Arctic sea ice, melting of the Greenland ice sheet, changes in precipitation patterns, and changes in vegetation and the behaviour of wildlife.

All three analyses of global temperature have been thoroughly and independently assessed by the IPCC, which is one of the most rigorous scientific review bodies in existence. Many thousands of scientists have dedicated their time to preparing and reviewing the most comprehensive and authoritative assessments of climate science available. In addition, governments from around the world have also reviewed the IPCC findings and, by consensus, approved the key findings in the summaries for policymakers and synthesis reports.

There is no doubt that the evidence for climate warming is irrefutable. The world’s leading scientists overwhelmingly agree what we’re experiencing cannot be attributed to natural variation in the climate over time, but is due to human activities; and if we do not act, climate change will continue apace with increasing droughts, floods and rising seas, leading to major damaging impacts to the natural world (loss of species and critical ecosystem services) and society (displaced human populations). The scientific evidence that backs calls for action at Copenhagen is very strong. Without coordinated international action on greenhouse gas emissions, the impacts on climate and civilisation could be severe.

Just over a week ago, the Royal Society, the National Environment Research Council and the UK Meteorological Office issued a joint statement not only supporting the findings of the 2007 IPCC report, but showing that recent scientific information further strengthens those conclusions, and concluded that they could not emphasise enough the body of scientific evidence that underpins the call for action now. Also, the joint sciences academies’ statement: global response to climate change (11 academies from developed and developing countries) concluded that climate change is real, that we need to prepare for the consequences, and urged all nations to take prompt action to reduce their greenhouse gas emissions.

If the heads of state arriving in 10 days cannot agree to a fair, ambitious and binding agreement to prevent climate change from becoming a runaway train, they won’t be able to blame the scientists. The science is clear. This week and next, the ball is in the negotiators’ court.