In order to understand the influence of urban forests in the thermo-hygrometric variation in the intra-urban area of the city of Curitiba, this study aimed to analyze the temporal and spatial variation of temperature and relative air humidity in each season and relate it with the presence of urban forests. For the collection of meteorological data were established 44 monitoring points in four transects in the urban mesh. In these points, mini-shields with Hobo(r) loggers were installed at fixed points on sign and traffic light posts. The temperature and relative air humidity monitoring was conducted during periods corresponding to the four seasons, with 22 days to collect and continuous data record at 15 minute intervals. In the four transects analyzed in the intra-urban area of Curitiba significative differences were found between the thermo-hygrometric monitoring points in all periods analyzed. Even in seasons of lower temperatures, autumn and winter, thermal differences were related to anthropogenic heat. The analysis of the longitudinal profile of the temperature revealed a curve similar to classic profile of urban heat islands, with the highest temperatures in more densely occupied areas and human activities, such as in the city center and south-center area. The lowest temperatures were found in residential districts and the suburbs, such as in the north and northwest areas of the city and the southern city border, in addition to the evidence of the cooling effect of urban forests present in the intra-urban area, as 'Barigui' and 'São Lourenço Parks'. The regions with the largest of permeable areas, concentration of forest remnants or public green space had lower temperatures and increased the relative air humidity.
urban trees; urban microclimate; air temperature
