Reports Past: The Intergovernmental Panel on Climate Change had released four assessment reports on the state of the climate as of 2007. The reports, which are the results of several UN-appointed scientific working groups, provide a comprehensive analysis of available climate research and suggestions for actions that might be taken to mitigate the impacts of a warming climate.
Despite the so-called climate debates about whether climate change is attributable to manmade causes, the reports have increasingly pointed to human activity as a major player in climate issues. In 2011, a special report was issued that strongly stated human-caused climate change would result in a warmer climate and more catastrophic weather events.
That report, Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (known as SREX), found that the earth’s warming trajectory would likely manifest itself in hotter days and more heat waves, storms, and floods, and possibly lead to droughts and to more frequent and intense cyclones and tropical storms.
“It also underlines the complexity and the diversity of factors that are shaping human vulnerability to extremes—why for some communities and countries these can become disasters whereas for others they can be less severe,” IPCC Chair Rajendra Pachauri said in a 2011 press release announcing the report.
The Present Report: The Fifth Assessment Report from Working Group I, which addresses the physical science of climate change, was released Monday along with a summary for policymakers.
The report makes the strongest assertion to date that humans are the driving climate change, saying that it’s 95 percent certain (up from 90 percent stated in the previous report) that “human influence has been the dominant cause of the observed warming since the mid-20th century.”
The report also contains ominous warnings about what to expect if the world’s nations are unable to curb greenhouse gas emissions, including sea level rise of up to 39 inches by the end of the century and global surface temperature increases of up 8.6 degrees Fahrenheit.
The report also includes a hard-negotiated worldwide carbon budget of less than 1,000 gigatons that could keep warming at the 2 degrees Celsius mark. According to the Guardian, the inclusion of the budget—more than half of which has already been expended—was the subject of heated discussions and fraught with political concerns.
Future Reporting: Monday’s report is the first of four to be released by the IPCC. The Working Group II report, which tackles issues of climate change impacts and adaptation, is slated to be released in March of 2014 and the Working Group III report, on matters of mitigation, is expected in April of 2014. A Synthesis Report will be delivered in late October 2014.
The reports will inform negotiations to create a legal framework for climate change action in 2015. UN Secretary General Ban Ki-Moon has urged world leaders to start working toward goals immediately.
“The goal is to generate the political commitment to keep global temperature rise below the agreed 2-degree Celsius threshold,” he said in a statement. “The heat is on. Now we must act.”