This blog post is a short summary of key points that are of current relevance to society from the physical science of climate change. It is based on the headline statements of a report published in 2021 by the Intergovernmental Panel on Climate Change (IPCC). The IPCC is a United Nations body responsible for providing impartial assessments of climate science. Its reports inform international negotiations on tackling climate change.| Climate Lab Book
The recent 6th Assessment Report of Working Group I of the Intergovernmental Panel on Climate Change (IPCC) is the result of years of diligent assessment of the latest scientific evidence on climate change building on several previous similar assessments. It was written by hundreds of authors, and openly reviewed by thousands of experts. Every word of the Summary for Policymakers was agreed by all 195 parties to the UNFCCC and at COP26.| Climate Lab Book
The latest Intergovernmental Panel on Climate Change (IPCC) report states that the global water cycle will intensify with continued global warming. This means fewer rainy days, but with more intense rain over many land regions, and more variability generally. More dry days and longer dry spells have the potential to lead to negative impacts on crop yields and food security, as reductions in water availability limit crop growth. The impacts on crops also depend on the timing of these longer dr...| Climate Lab Book
The recent IPCC AR6 WGI report summarises the state of knowledge of physical climate science, but the final version of the Summary for Policymakers (SPM) did not include a figure showing a range of indicators of our warming planet.| Climate Lab Book
Using up the carbon budget| Climate Lab Book
The figures in the IPCC AR6 WGI SPM are a huge improvement over previous reports. However, one minor quibble is with the lack of observations shown. This brief post makes a figure available which is based on IPCC AR6 WGI SPM Figure 8, but with some observations added to show how global surface temperature and Arctic sea ice area have varied, compared to the model simulations. In my view this is a scientific improvement over the original version.| Climate Lab Book
The Working Group I (WGI) component of the IPCC 6th Assessment Report (AR6) has been released. One key development since AR5 was the involvement of professional graphic designers in creating the figures for the Summary for Policymakers (SPM). As a result, the graphics are clear and usable, having been user-tested through several design iterations. The data underlying the figures are also openly available.| Climate Lab Book
Record extreme temperature events are increasing in frequency as the climate warms. Several of these records have been surprising, in that they have been far above the previous record event for that location. Longer and earlier records, often possible through data recovery from undigitised archive material, would help quantify the risks of such record extreme temperature events.| Climate Lab Book