Just last Friday, the Intergovernmental Panel on Climate Change issued its 5th Assessment Report since 1990, and the related Summary for Policymakers. The report took six years to produce and is considered the most comprehensive review of the scientific evidence for man-made climate change available. 830 scientists from 85 countries contributed, reviewing 9,200 research studies on matters ranging from rising sea levels to ocean acidification, to the impact of volcanic activity, to name just a few.
Over the coming weeks, we’ll be reviewing the IPCC findings in some detail. But given the hundreds of pages involved, permit me to begin with a thumbnail sketch by Sir John Houghton, former Co-Chair of the IPCC, Oxford University professor, leading Christian author and thinker, and friend of the beloved pastor, John Stott. In a British website connecting the environment, science and Christianity, Houghton summarized the main findings of the report as follows:
1) That it is extremely likely (i.e. more than 95% probability) that human influence on climate caused most of the observed increase in global average surface temperature from 1951- 2010.
2) That there is high confidence that this has led to warming of the ocean, melting of snow and ice, a rise in global mean sea level and to more climate extremes with increased intensity.
3) Further warming will result from continued emissions of greenhouse gases, causing changes in all parts of the climate system. Considerable reductions in greenhouse gas emissions will be required if climate change is to be limited.
4) Under almost all possible scenarios a rise of 1.5C is predicted by the end of this century relative to 1850 to 1900 temperatures, but in some scenarios the rise is greater than this. Most scenarios predict further warming beyond 2100.