Last week, the United Nations' Intergovernmental Panel on Climate Change issued another report stating what has been obvious to most scientists for decades about the effect of greenhouse gas emissions on rising global temperatures and mounting environmental challenges.
When the last IPCC report was issued in 2007, the consensus among leading climate scientists that human activity was the culprit in global warming was as high as 90 percent. Since then, the percentage of like-minded scientists has risen to 95.
"This report confirms with even more certainty than in the past -- that it is extremely likely that the changes in our climate system for the past half a century are due to human influence," Michel Jarraud, secretary general of the World Meteorological Organization, said.
According to the new report, sea levels are expected to rise 9 feet, 10 inches by 2300, thanks to ice and glacier melts already underway. Coastal cities will be inundated. An estimated 15 to 40 percent of carbon dioxide will be trapped in the atmosphere for 1,000 years, thanks to a world-wide addiction to fossil fuels.
The long-term negative effects of global warming won't inconvenience just a generation or two. Earth's inhabitants will be dealing with drought, rising sea levels, heat waves and floods -- the fallout from a lack of environmental stewardship -- for centuries, according to the report.
The IPCC document is a clarion call to all governments to commit to addressing the challenge of climate change by reaching a U.N. accord by 2015. This call to meaningful action has opponents in the industrialized and rapidly industrializing world who have a vested interest in denying the science for economic reasons.
Climate change deniers trumpet the fact that temperatures have not risen as quickly in the last 15 years as some had predicted, despite record levels of emissions. But ocean temperatures continue to climb, the report noted, which will bring their own harmful consequences.
Even after the glaciers retreat and large cities are coping with routinely rising water, there will be those who will continue to deny that human activity played a role in these disasters. As the IPCC report makes clear, the time for accommodating the opinions of science deniers is past. Action to avert catastrophe is needed now.opinion_editorials