Dynamic estimation of urban heat exposure for outdoor jogging: Combining individual trajectory and mean radiant temperature

Abstract

Limited research has been devoted to exploring individual heat exposure within urban environments for those engaging in jogging activities, particularly in developing countries. Therefore, we proposed an analytical framework to investigate the differences in individual heat exposure among different motion, temporal, and spatial jogging patterns. We combined massive jogging trajectories and modeling mean radiant temperature to estimate heat exposure dynamically, using Chengdu, China, as a case. The findings indicate that mean radiant temperature varies over time and across spaces due to changing radiation and complex urban environments. Individual jogging behaviors exhibit significant temporal fluctuation and spatial heterogeneity, necessitating dynamic exposure assessment. Jogging patterns influence the heat exposure. Regarding motion patterns, looping jogging (847 °C·min) has lower sum heat exposure than non-looping (1003 °C·min). From temporal dimensions, weekend joggers face higher heat exposure than weekdays. For spatial patterns, joggers along east-west (1049 °C·min) experience higher heat exposure than along a south-north direction (866 °C·min); roadside jogging exhibits the lowest sum heat exposure and park jogging demonstrates the highest one because of the duration of jogging. Heat emission, building shade, and physical activity collectively affect heat exposure. These findings provide valuable insights for urban planners and decision-makers for promoting outdoor recreational activities and enhancing healthy urban environments.