Changes in bioclimates in different climates around the world and implications for the built environment

Underlying trends of the long-term summer and winter discomfort in terms of heat and cold stresses in the major climate zones and sub-zones of the Köppen-Geiger world climate classifications during the 20th century were investigated. Decreasing trends of cumulative cold stress and increasing trends of cumulative heat stress were observed in all the major climate types and sub-types. This could have significant implications for building designs and energy use in the built environment. A reduction in cold stress would lead to less heating requirement and an increase in heat stress more cooling. Analysis was also conducted for the world climates in eight regions – North America, South America, Europe, Africa, Asia (Far East), Asia (Southeast), Asia (Middle East), and Australia and Pacific Islands. It was found that South America, Africa and Asia (Southeast) showed an increasing trend in the annual cumulative stress suggesting that the increase in cumulative heat stress outweighed the reduction in cumulative cold stress. Expected increases in the demand for electricity with greater carbon emissions present a challenge to building researchers and energy and environmental policy makers.