The human climate of tropical cities: an overview.

A review of physioclimatic maps at global, regional, and local scales is made of the tropical environment. At the global scale the highest heat load is located seasonally in arid subtropical cities. High sultry conditions (heat and humidity) prevail during the whole year in equatorial cities. In most inner areas of the tropics, urban areas with wet/dry seasons and days are seasonally hot or sultry while nights may be cool or tolerably warm. In some mountain tropical climates (altitudes between 1600 and 1900 m above sea-level) the stress due to either heat or cold is minimal. From the point of view of human comfort the bioclimate in these cities would approach the ideal (in the shade). One has to keep in mind, however, that even in these climates for a person walking on a street at noon, comfort is reduced drastically by the high radiation levels.