An international global warming conference approved a report on climate change Friday, chairman Rajendra Pachauri said, after a contentious marathon session that saw angry exchanges between diplomats and scientists who drafted the report. "We have an approved accord. It has been a complex exercise," Pachauri told reporters after an all-night meeting of the International Panel on Climate Change. Several scientists objected to the editing of the final draft by government negotiators but in the end agreed to compromises. However, some scientists vowed never to take part in the process again. "The authors lost," said one scientist. "A lot of authors are not going to engage in the IPCC process anymore. I have had it with them," he said on condition of anonymity because the proceedings were supposed to remain confidential. An Associated Press reporter, however, witnessed part of the final meeting. The climax of five days of negotiations was reached when the delegates removed parts of a key chart highlighting devastating effects of climate change that kick in with every rise of one degree Celsius (1.8 degrees Fahrenheit), and in a tussle over the level of confidence attached to key statements. The United States, China and Saudi Arabia raised the most objections to the phrasing, most often seeking to tone down the certainty of some of the more dire projections. The final report is the clearest and most comprehensive scientific statement to date on the impact of global warming mainly caused by man-induced carbon dioxide pollution. It predicts that up to 30 percent of species face an increased risk of extinction if global temperatures rise 2 degrees Celsius (3.6 degrees Fahrenheit) above the average in the 1980s and '90s. Areas that now suffer a shortage of rain will become even more dry, adding to the risks of hunger and disease, it said. The world will face heightened threats of flooding, severe storms and the erosion of coastlines.