Background of the IPCC's Latest Climate Report

On Friday, September 27, the Intergovernmental Panel on Climate Change (IPCC), the world’s foremost authority on climate change released the first part of AR5, its first big report in six years. The AR5 is a scientific inventory of the state of our knowledge on climate science.

AR5 will take more than a year to be fully released. It will be unveiled in four different parts. The first part is being released represents a summary of the work done by what is known as Working Group I, which is why it is called WGl AR5. It covers the physical science of climate change and gives the big picture including things like temperature changes, sea-level rise and ocean acidification. The full WG1 AR5 report will be released on Friday October 4, 2013.

The first IPCC report was released in 1990, followed by a “supplementary” report published in 1992. The second assessment report came out in 1995, followed by more in 2001 and 2007. And now the fifth assessment report is being released.

Led by Rajenda Pachauri, the IPCC is a scientific group set up 25 years ago by the United Nations. The IPCC provides policymakers with up to date scientific information about climate change. While the IPCC does not do its own research, it assesses research in climate science and highlights the most important findings, and shares its findings in assessment reports. As part of the peer review process a total of more than 800 climate scientists from 85 countries contribute to these reports either as authors or review editors.

The science contained in these reports tends to represent estimates that are conservatives, consequently many feel that the report is understated. However, scientific conclusions are commonly conservative and understated.

The Working Group II report, or WGll AR5, will be released in March 2014. It will address the actual impacts of all that climate change and adapatation efforts.

The Working Group lll report, or WGlll AR5, will be released in April 2014. It will look at mitigation opportunities.

The final section, or what is called a Synthesis Report will be released one year from now in October 2014, it will summarize and consolidate the findings from WGl AR5, WGll AR5, and WGlll AR5.

Salient Conclusions from WGl AR5 Summary:

The IPCC is revising up its level of confidence that humans are affecting the climate from 90 percent to more than 95 percent. This is about as close to certainty as science gets.

Land temperatures continue to rise but the rate at which they are rising has slowed somewhat. One prominent explanation is that oceans have been absorbing more heat.

To see the IPCC AR5 WGl Summary, headline statements for Policymakers click here.