The Union of Concerned Scientists, released a report in July titled “Killer Heat in the United States.” The report provides an assessment of the impact of extreme heat and the heat index on different population groups, including outdoor workers and city dwellers. The report also summarizes the analyses of three different greenhouse gas emissions scenarios on the heat index of different regions across the U.S. over the next century.
The analysis uses a set of 18 climate models to predict changes in the heat index throughout the next century. According to the group, the findings show “rapid, widespread increases in extreme heat that are projected to occur across the country due to climate change, including conditions so extreme that a heat index cannot be measured.” The results found that the magnitude of the temperature increases depend heavily on how quickly actions are taken to reduce heat-trapping emissions.
Along with the report, the Union for Concerned Scientists released two tools to help visualize these findings. The first, an interactive mapping tool, allows users to view the expected increases in heat indexes throughout the whole United States in historical, midcentury, and late century time frames. This data can be further analyzed by selecting the level of action taken against climate change – either ‘no action’, ‘slow action’, or ‘rapid action’. A second tool allows users to search their own city or county to view how the number of “extreme heat” days might change throughout this century based on a low action, slow action, or rapid action (i.e., aligned with commitments from the IPCC Paris Agreement) on climate change.