The Heat Vulnerability is an index that was developed by NASA and Groundwork USA (Groundwork USA) to assess a community’s potential vulnerability to climate change. Data is available at the census block level and integrates information about the amount of tree coverage (tree canopy), impervious surfaces, land surface temperature, and percentage of households in poverty.
How is it scored?
The heat vulnerability index was calculated using the methods described by Groundwork USA and converted to the report card scale for each census block (Table 1). The population weight of a census block was calculated by multiplying the census block population by the proportion of the census block occurring within a watershed. The population-weighted census block scores were summed to calculate the watershed score. Watershed scores were population-weighted to calculate the overall region score for southeast Michigan.
Table 1. Heat Vulnerability Index scoring.
Heat Vulnerability Index | Report Card Score | Report Card Grade |
4 to 0 | 0–19 | F |
0 to -1 | 20–39 | D |
-1 to -2 | 40–59 | C |
-2 to -3 | 60–79 | B |
-4 to -4 | 80–100 | A |
Data source: Tree canopy and impervious surfaces were calculated from the National Land Cover Database 2019 data, land surface temperature was calculated from Google Earth Engine, and percentage of households in poverty was calculated from the US Census Bureau’s 2019 data.