Human link to climate change ‘unequivocal’ scientists say
February 9, 2007
Last Friday, the worlds of science and policy met to erase some major clouds of doubt and uncertainty. For the first time, researchers and leaders came together to the announcement that global warming is “unequivocal” and that human activities are almost definitely the primary cause. The Intergovernmental Panel on Climate Change released the first of four reports due this year in Paris to document the planet’s warming in the past century and the warming to come as we continue to pour greenhouse gases into the atmosphere.
p. The report confirmed what many scientists have been saying for more than a decade: the increasing emissions of carbon dioxide and other greenhouse gases are trapping more of the sun’s energy as heat. In the atmosphere, trapped gases trap heat, and the increases in these gas levels are creating widespread global problems — from melting ice caps and rising sea levels to droughts, famines and unpredictable weather.
p. “Since 2001, there has been a torrent of new scientific evidence on the magnitude, human origins and growing impacts of the climatic changes that are under way,” John Holdren, the president of the American Association for the Advancement of Science, told the New York Times. “In overwhelming proportions, this evidence has been in the direction of showing faster change, more danger and greater confidence about the dominant role of fossil-fuel burning and tropical deforestation in causing the changes that are being observed.”
p. Previous reports have indicated the possibility and even likelihood of these events, but this most recent IPCC report is the first to try to put an end to the uncertainty on the issue, reporting with greater than 90 percent confidence that global warming is becoming a dangerous result of human activity. The report stated that the past century saw a 0.74 degree Celsius increase in global temperatures, predominantly in the latter 50 years. Current greenhouse gas concentrations are indicating an increase of 0.2 degrees Celsius every decade for the next 20 years. What happens beyond that is undoubtedly affected by the decisions made now concerning human activities and emission levels.
p. The United States has been the world leader in greenhouse gas production; our 5 percent of the global population has created 25 percent of the problematic emissions. Along with 112 other countries participating in the IPCC, the Bush Administration — which had previously avoided acknowledging the link between human activities and global warming — welcomed and supported the findings,
p. “The findings, which governments have agreed upon, leave no doubt as to the dangers that mankind is facing and must be acted upon without delay. Any notion that we do not know enough to move decisively against climate change has been clearly expelled,” Yvo de Boer, the executive secretary of the United Nations Framework Convention on Climate Change, stated in a press release after the report was presented Friday.
p. It would be misleading to suggest that with the publication of this report, scientists know everything they need to know about climate change. There is still plenty of uncertainty remaining on these issues, but the question of if has shifted into questions of “when” and “how.” The climate of the planet is changing, and the implications of that are vast, complicated and only beginning to be understood.
p. The questions that remain, even with our ever-increasing pile of supporting evidence, graphs and solid scientific research, aren’t going to be easy to answer, either. Yes, global climate change is happening; the earth is getting warmer and it’s our fault. So, what are we going to do about it now?