Effects of a moderate sized city on human thermal bioclimate during clear winter nights

The human thermal bioclimatic effects of urbanization and natural topographic features (the ocean and hills) were investigated during clear winter nights in Christchurch, New Zealand. Results are presented in terms of the amount of clothing insulation required to balance the body heat budget equation of a standing person with no change in body heat storage. The ordering of urban-rural land use zones from lowest to highest clothing requirements was: CBD, light industrial-commercial, residential and rural. Air temperature accounted for most of the variation in clothing requirement with the model used and weather conditions investigated here followed by environmental thermal radiation. The oceans and hill slopes had an effect comparable to that of most of the urban area and required less clothing than did all land use zones except the urban CBD.