Unravelling key environmental factors influencing urban park visits: Thermal comfort and air quality

Urban parks play a vital role in shaping physical and mental health. Walking and cycling to local urban parks have become increasingly popular since the COVID-19 pandemic, whereas the climate change and air pollution continue to spur health risks for outdoor activities. Existing literature have focused on measuring the impact of temperature on park attendance, mainly using incomplete or short-term park visit data from field investigations. However, there is a lack of research on how thermal comfort factors (e.g., heat and humidity) and air quality indices - individually and synergistically - enhance or reduce visits to urban parks, particularly with quality official daily park visit data spanning an entire year. In response to the research gap, this study conducted a comparative case study of two urban parks in Shanghai, covering descriptive, correlation, and regression analyses of how weather and air quality mediate daily park attendance from April 1, 2020 to March 31, 2021. This study identifies that temperature, humidity, and the 'Heat Index' combining heat and humidity are strong parameters influencing the number of park visits, while the impacts of air quality indices are mostly trivial. Urban humid heat, a weather condition becoming more frequent with the rise of extreme heat events in Shanghai's recent summers, received much less attention than the sheer degree of temperature, threatening healthy outdoor activities in parks. These findings provide timely and important implications for better urban park planning, design, and management for promoting outdoor activities while reducing health risks.