The continuing trend of air warming and humidifying in Kowloon, Hong Kong—is there an effective intervention?

The Kowloon Peninsula, an urban area of Hong Kong, might be one of the most studied cities in terms of urban climate in the world. Both annual mean urban air temperature and humidity have been on the rise following the continual increase in the building volume and continual reduction in the average wind speed in the urban canopy layer. The observed urban warming and humidifying phenomena are a direct result of the city form (i.e., the city shape and size), including the building height and density. We call for a system-of-systems approach to be adopted in urban climate studies.