Human-perceived temperature changes linked to local climate zones under extreme hot and cold weathers: A study in the North China Plain

Abstract

Human-perceived temperature (HPT) describes the combined effects of multiple meteorological factors on human body. However, the relationship between HPT, local climate zones (LCZs), and extreme weather events remains unclear, especially for rapidly urbanizing regions including the North China Plain (NCP), one of the most populated regions vulnerable to heat stress. Here, we examine the HPT changes associated with LCZ and temperature extremes by taking NCP as an example. We show that HPT in built-up areas of NCP is warmer than that in natural surfaces, with an average summer heat index of 27.69 °C and 27.26 °C, respectively. Mid- and high-rise buildings exhibit higher HPTs than low-rise. This difference is even larger in denser building agglomerations (0.80 °C in compact areas versus 0.75 °C in open zones). Urban thermal environment is more comfortable in greenery, particularly tree-covered areas. A comparison between normal and extreme weather conditions reveals a remarkable cooling effect by urban greenery. Nevertheless, during extreme heat, urban trees may have diminished cooling and potentially exacerbate humid heat threat, likely via increased water vapor by evapotranspiration. Under extreme conditions, LCZs 7 and 10 demonstrate high HPT variability and vulnerability. These findings provide valuable insights for improving urban climate resilience, landscape planning, and sustainable development.