Modeling Indoor Heat Vulnerability and Future Cooling Needs: Insights from the NOLA HEAT-MAP Study

The indoor residential environment is a critical yet underexamined determinant of public health, particularly during extreme heat events. People in the U.S. spend roughly 90% of their time indoors, making indoor thermal exposure a key yet often overlooked, component of heat vulnerability. The level of residential protection against climate hazards depends on socioeconomic factors, but in the U.S., decades of systemic housing discrimination mean that housing quality issues disproportionately fall on racialized minority and low-income populations.

The New Orleans Home, Environment, and Ambient Temperature: Measurements and Analysis for Preparedness (NOLA HEAT-MAP) Study assessed indoor thermal vulnerability to inform equitable resilience strategies. We enrolled 114 participants from high-urban-heat neighborhoods in New Orleans, LA, collecting demographic and housing data, continuous indoor temperature and humidity measurements over two- or four-week periods, and daily self-reported physical and mental health surveys.

Modeling results show that outdoor temperature, air conditioning type and use, and homeownership status are key predictors of indoor heat exposure. Notably, homeowners were twice as likely as renters to experience the highest overnight indoor temperatures (62% vs. 38%). Across tenure types, homes relying on window units struggled to maintain 80°F (26.6°C) once outdoor temperatures exceeded 90°F (32.2°C)—an important threshold given New Orleans’ residential cooling standard requiring rental units to maintain temperatures of 80°F (26.6°C) or below.

To understand how these challenges may change over time, we estimated the number of days exceeding 90°F in New Orleans using LOCA2 downscaled CMIP6 climate projections. We found that days exceeding 90°F (32.2°C) may rise by 50% by 2075, reaching approximately 150 days annually under SSP5-8.5. In this presentation, we will discuss how these findings suggest escalating cooling needs that could exacerbate existing inequities in thermal safety, and highlight the need for interdisciplinary, climate-informed research to support adaptive public health and resilience.