Large urban parks summertime cool and wet island intensity and its influencing factors in Beijing, China

Abstract

Construction of urban parks has long been proved as an effective way to mitigate urban heat island effect, and better arrangement of green spaces in a city is expected to help regulate urban climate. To provide further empirical evidence and guidance for urban green spaces planning and design, field measurement of summertime air temperature and relative humidity was conducted in and out of 10 large urban parks in Beijing, China. Averaged daytime and nighttime park cool and wet island intensity were 1.09 ℃, 1.48 % and 3.63 ℃, 4.25 % respectively. Parks’ influence on local-scale climate extended as far as over 1km during summer nights, and more effective cooling effects were provided within approximately one-park width. Among all influencing factors, park size plays dominant role in regulating nighttime local-scale climate in parks’ adjacent area, while vegetation coverage around sampling points out of urban parks also has significant contributions, indicating that large urban parks and their surrounding urban greenery interact to affect neighborhood climate. Park size was the only factor found correlated with nocturnal park cool and wet island intensity. Results of this study provide additional information on large urban parks’ local-scale climate effect and give insights to future urban green spaces planning and design practice.