Almost 1 in 4 people in the United States are socially vulnerable and have low resilience to extreme heat exposure, according to new U.S. Census Bureau data.

The Community Resilience Estimates (CRE) for Heat, an experimental data product released in April, measures the capacity of individuals and households in a community to withstand the stress of exposure to extreme heat based on their social characteristics.

CRE for Heat suggests greater social vulnerability and geographic variation compared to the standard CRE.

When measuring social vulnerability to heat exposure, the proportion of individuals with three or more risk factors increases from 21.6% in the standard CRE to 23.8% in CRE for Heat.

Similarly, the share with 0 risk factors decreases from 34.6% in the standard CRE to 31.7% in CRE for Heat.

In other words, when accounting for additional housing and transportation characteristics, more people in the United States are socially vulnerable or less resilient to rising heat temperatures.

The first CRE was published as an experimental data product in June 2020 to provide information about the COVID-19 pandemic. It was also published to garner feedback from data users and stakeholders on the quality and usefulness of such a product.

KER reached out to the CRE team to further discuss the product and was particularly interested in how the CRE could be leveraged for measuring social vulnerability to heat exposure.

In consultation with KER, the CRE modified three of the 10 risk factors to adjust for social vulnerability to heat exposure.

While the standard CRE simply had a unit level crowding measure (0.75 people or more per room), CRE for heat has a housing-quality exposure indicator that also accounts for structure type or where people live (mobile home, boat, RV, or other).

Also, the original CRE has an indicator for no household vehicle but the CRE for Heat’s transportation exposure indicator also contains commute type (public transportation, walking, biking or other nonpersonal vehicle method).

Finally, while the CRE simply had a poverty indicator, the CRE for Heat’s financial hardship indicator also includes whether the household’s housing costs are greater than 50%.

Even though the number of risk factors didn’t change in the CRE for Heat, some characteristics or conditions like transportation modes were added. A person only needs to meet one of the conditions to receive a risk factor flag. For example, if a household does not have unit-level crowding but lives in a mobile home, it will be flagged for having a housing quality risk. If the household meets both conditions, it’s only flagged once.