Understanding Variability in Adaptive Capacity to Extreme Heat Among Public Bus Riders in Tennessee: A Quantitative Study

Background and Purpose:

Extreme heat is an escalating public health threat, particularly for transit-dependent populations who face heightened exposure but remain underrepresented in climate vulnerability research. This study applies the Extreme Heat Vulnerability Framework, in combination with Environmental Justice, Mobility Justice, and Title VI of the Civil Rights Act, to examine how sociodemographic characteristics, adaptive capacity (knowledge, attitudes, and practices—KAP), and access to public information influence heat-related experiences among public bus riders in Tennessee.

Methods:

A cross-sectional online survey was conducted with 355 public bus riders across Tennessee. The survey gathered data on participants’ demographics, travel behavior, health outcomes, and use of public information sources such as weather alerts and transit apps. Quantitative analyses included multiple logistic regression, generalized ordinal logistic regression, multiple linear regression, and LASSO regression. Five hypotheses were tested to explore predictors of adaptive capacity and health outcomes.

Results:

Significant disparities emerged in adaptive capacity and heat-related health outcomes. Riders who lived in Knoxville, identified as women, were older, had disabilities, used medications that increase heat sensitivity, or held a driver’s license were more likely to exhibit higher levels of heat-related knowledge and protective behaviors. Among all predictors, access to weather alerts and transit information—especially via mobile apps—was the most consistent and robust factor associated with greater adaptive capacity. Interestingly, individuals with stronger heat-related knowledge, more proactive attitudes, and more frequent engagement in protective behaviors were also more likely to report experiencing heat-related symptoms and seeking medical care. This suggests that increased awareness and behavioral responsiveness may influence self-reporting of health issues. Notably, digital access gaps were observed among older and economically marginalized riders.

Conclusions and Implications:

The findings underscore the urgent need for inclusive and equitable heat mitigation strategies in public transit systems. These include improving infrastructure (e.g., shaded stops, air-conditioned buses), enhancing targeted health communication, and addressing digital access disparities. This study demonstrates the value of justice-centered, interdisciplinary approaches to climate adaptation, particularly in supporting the resilience and health of transit-reliant populations disproportionately affected by extreme heat.