ESTUDO COMPARATIVO DE FAIXAS DE CONFORTO OBTIDAS PARA O ÍNDICE TÉRMICO UTCI PARA DUAS CIDADES BRASILEIRAS

Abstract

Urban growth accompanied by impacts on landscape and natural environments will require guided compaction schemes in urban areas, particularly in developing countries. Human-biometeorological indices such as UTCI could guide this process, as they provide a clear account of expected effects on thermal sensation from a given change in outdoor settings. However, an earlier step should optimally include an adequacy test of suggested comfort and thermal stress ranges with calibration procedures based on surveys with the aimed population. This paper compares obtained comfort ranges for two different locations in Brazil: Belo Horizonte, 20°S, Cwa climate type and Pelotas, at 32°S, with a Cfa climate type, thus with a pronounced difference in local latitude. In each city, a set of outdoor comfort campaigns has been carried out according to similar procedures, covering a wide range of microclimatic conditions over different seasons of the year. In Belo Horizonte, the sample obtained comprises 1691 thermal votes with measurements in four different locations over four campaigns. In Pelotas, the sample was considerably smaller (ongoing research) and comprises 257 votes distributed in ten measurement campaigns at five different points. Obtained results indicate a reduction of neutral temperatures around 2°C (in UTCI units) as a possible latitude and local climate effect for the southernmost location. Comfort ranges are initially wider for Pelotas than in Belo Horizonte. A lower UTCI value was found in Pelotas for the lower threshold of the comfort band as compared to the suggested band for the index. A possible explanation for that is a longer exposure to cold conditions as buildings seldom are provided with heating systems.