Quantitative seasonal outdoor thermal sensitivity in Guangzhou, China

Abstract

Recently, increasing attention is being given to the outdoor thermal environment. However, current results on thermal sensitivity are not uniform. Therefore, a field survey was conducted in a typical hot summer and warm winter city, Guangzhou, China. The qualitative sensitivity of microclimatic parameters was analyzed by standardized regression coefficient (SRC). Physiological Equivalent Temperature (PET), Universal Thermal Climate Index (UTCI), and Standard Effective Temperature (SET*) were modified and tested for sensitivity using linear regression. The results showed that people have different sensitivities to thermal parameters in different seasons, among which air temperature (Ta) is the most sensitive parameter, followed by mean radiation temperature (Tmrt) and wind speed (Va), whereas relative humidity (RH) had little effect. SET* had the best consistent thermal sensitivity of Guangzhou's people, compared with PET and UTCI. Generally, MTSV may change one grade with the ΔTa= 5.2 °C, ΔTmrt= 13.5 °C, or ΔVa= 1 m/s in spring; ΔTa= 3.9 °C, ΔTmrt= 11.9 °C, or ΔVa= 1 m/s in summer; ΔTa= 5.9 °C, ΔTmrt= 15.6 °C, or ΔVa= 1 m/s in autumn; ΔTa= 15.3 °C, ΔTmrt= 38 °C, or ΔVa= 2.3 m/s in winter. Therefore, the thermal sensitivity of microclimatic can support a reference for urban planning.