Spatial-temporal dynamics and associated driving forces of thermal comfort in 32 major cities of China

Abstract:

Urbanization, an inexorable trend worldwide due to industrialization and economic development, brings with a unique set of issues that affect land use patterns, urban environmental quality, and even standard of life. One of the most concerning environmental phenomena related to urbanization is known as the Urban Heat Island (UHI) effect, which can affect human health by contributing to thermal discomfort. Despite numerous previous studies devoted to investigating the temporal evolution, process, influencing factors of urban thermal comfort in individual cities, the spatial-temporal dynamics of thermal comfort in multiple cities across large geographic regions have not been well-documented. Here, we presented an effort to detect seasonal variations of spatial-temporal patterns in urban thermal comfort during 2001-2019 across 32 major Chinese cities using MODIS data. Overall, our results showed that modified thermal comfort index (MTHI) at most cities (66% of all) increased from 2001 to 2019, which indicates that urban thermal comfort in China deteriorated in summer time during the past two decades. However, temporal changes in winter were not evident. The dominant driving forces of urban thermal comfort vary across different climatic zones, and the influence of population growth on urban thermal comfort have gradually increased. Our work revealed that the spatial distribution and temporal variation of urban thermal comfort, and therefore provides scientific basis for urban management and planning toward more sustainable trajectories.