A Heat Vulnerability Index, developed by NASA and Groundwork USA, is a watershed indicator in the report card. This index includes four metrics: tree canopy, impervious surface, land surface temperature, and households in poverty. The index identifies places where there is greater vulnerability of people to heat-related and flooding-related risks, which are often in neighborhoods with race-based housing discrimination. Other groups at risk are communities of color, low-income communities, children, and the elderly. This index can help managers prioritize locations for restoration projects such as tree plantings and conversion of abandoned impervious surfaces to green space.
How is it scored?
The Heat Vulnerability Index is an indicator of climate-safe neighborhoods that includes metrics for tree canopy, impervious surface, land surface temperature, and households in poverty. Data is at the Census Block level. Land surface temperature (LST) data are from NASA and USGS through the Google Earth Engine and cover a 6-year range. The Multi-Resolution Land Consortium (MRLC) provides data on impervious surface (USGS) and canopy cover (U.S. Forest Service). Poverty and population are from the U.S. Census Bureau.
The 2022 report card had the following data: LST was from 2014–2020, canopy cover was from 2016, impervious surface was from 2019, and poverty and population were from 2020. The 2023/2024 report card had the following data: LST was from 2015–2021, canopy cover, impervious surface, poverty, and population were from 2021. The 2025 report card had the following data: LST was from 2016–2022, canopy cover, impervious surface, poverty, and population were from 2022. The 2026 report card had the following data: LST was from 2017–2023, canopy cover, impervious surface, poverty, and population were from 2023.