Heat Monitoring in the New York City Subway System

New York City (NYC) is facing significant challenges as a result of the rapidly changing climate. Many facilities, including underground transportation infrastructure, will be greatly affected, particularly by the increasing frequency of heat waves. Elevated temperatures in the NYC subway system during these heat waves could pose risks to the health and safety of both commuters and subway personnel, as well as to the infrastructure itself. However, the full extent of these temperature impacts remains uncertain. Therefore, this study conducts a comprehensive investigation into the temperature effects and their implications within the subway system.

Temperature and relative humidity data were collected using sensors and thermal infrared cameras in several underground stations across NYC in the Bronx, Brooklyn, Manhattan and Queens. Using air temperature and relative humidity values, heat indices were calculated based on Rothfusz regression equation. Initial results show that the mean heat index differences (platform level – street level ) between platform level and street level for the month of July 2024 were -1.5^oF (for stations with air tempering systems), 2.34^oF (for stations with fans), and 2.37^oF (for stations with neither air tempering systems nor fans). The findings also highlight critical areas where heat management is most needed, suggesting targeted interventions to mitigate heat buildup.