A influência da urbanização no clima das cidades de Petrolina/PE e Juazeiro/BA.

Abstract

The intense urbanization observed in the last decades have caused important environmental changes around the world with emphasis to the changes in the climatic conditions and air temperature increases in the urban cities areas. This study evaluated the effects of urbanization on the climate of the cities of Petrolina in Pernambuco state and Juazeiro in Bahia state, municipalities with approximately five hundred thousand people, located in the heart of the brazilian semi arid region. To evaluate the influence of three different types of urban space on the microclimate, the field experiments were conducted during the winter (August/2007) and summer (December/2007 and January/2008). For both, were installed, while three micrometeorological stations in the following places: (i) commercial urban area with asphalt coating on the surface; (ii) living urban area with coated in parallelepiped (paving) on the surface; (iii) entertainment urban area (park) with the surface coating lawn. Besides the analysis data obtained in these three locations, comparisons were made with data of the same seasonal periods of each urban area and the rural area obtained in the meteorological station of the Federal University of the San Francisco Valley, located in Petrolina. The observed values for the maximum temperature at the surface in the urban area were 69.0ºC in summer and 50.2ºC in winter and higher than those in rural areas, 39.3ºC in summer and 33.1ºC in winter. The records of the maximum air temperature also showed the same pattern: urban area with 38.2ºC in summer and 32.5ºC in winter and rural area with 37.2ºC in summer and 31.9ºC in winter. During the summer, with higher density urban areas had discomfort in the afternoon heat and the heat island during the night, with intensity of 7.0ºC in asphalt and 6.0ºC in the area of paving, and park. Therefore, the results obtained in this study confirmed the hypothesis that urban structures influence the climate of the cities studied.