Observed Trends and Future Changes in the Intensity, Frequency, and Duration of Very Hot Weather in Hong Kong

Project: Research

View graph of relations


  • Wen ZHOU (Principal Investigator / Project Coordinator)School of Energy and Environment
  • P W CHAN (Co-Investigator)
  • Deliang Chen (Co-Investigator)
  • Michael HERZOG (Co-Investigator)
  • Riyu Lu (Co-Investigator)
  • Mark Oliver WENIG (Co-Investigator)


As global warming impacts continue to occur across the Earth owing to increased anthropogenicactivities, the potential for the intensity of extreme weather will become more severe across the globe.Hot weather and related extremes have attracted global attention especially based on record-breakinghigh temperatures, with little consideration of the effect of humidity on heat perception. Heat perceptioncarries immense economic, social and environmental implications and should therefore be included invery hot weather studies. Essentially, even if air temperature remains unchanged, we feel hotter (ourperception of heat) when it is more humid. This is why humidity is such an important parameter of heatperception, especially in Hong Kong and along the humid South China coast during summer.This study aims to provide statistical and modeling evidence on observed trends and future projectionsof very hot weather in Hong Kong, as such studies can empower early detection of the disaster andprovide opportunities for mitigation and adaptation. To make the projection, statistical downscalingtechniques will be applied to state-of-the-art Coupled Model Intercomparison Project Phase 5 (CMIP5)outputs to acquire a daily maximum heat index. This will allow us to identify changes in decadalcharacteristics of very hot weather in this century in terms of frequency, duration, and intensity.Representative concentration pathways (RCP) 4.5 and 8.5 will be used to evaluate how differentscenarios would affect very hot weather.The heat index projection provided by this study would give a clearer assessment of hot-weather-relatedrisk by overcoming the limitation highlighted. Hence, our study will find more applicability with awider audience. For example, the heat index can be related to labor capacity, hospitalization rates, andelectricity consumption to some extent. The long-term projection provided here would also be helpfulfor the labor sector, public health, and electricity policy planning


Project number9042558
Grant typeGRF
Effective start/end date1/01/1814/12/21