Impactos da urbanização e calor antropogênico em eventos extremos de chuva e temperatura em Manaus: estudo de modelagem urbana

Abstract

This study offers an in-depth perspective on the effects of urbanization in Manaus, exploring the interactions between urban presence, rainfall extremes and Anthropogenic Heat Flow (AHQ). The first part highlighted the significant influence of urbanization on the intensification of extreme rainfall events, modifying the temporal and spatial patterns associated with this change. By replacing forested areas with urban surfaces, the diurnal precipitation pattern was modified, prolonging the duration of extreme precipitation systems over the urban area and increasing the risk of flooding. The urban configuration contributed to the increase in air and surface temperatures, impacting the latent heat flow and influencing the behavior of precipitation. Urban areas, with materials that retain heat, resulted in more intense rainfall, while forested areas maintained frequent but lower intensity rainfall favored by evapotranspiration. By exploring anthropogenic influence, the second phase estimated the QAH in Manaus. Vehicular, stationary and metabolic sources contributed to an average of 13.04 W/m2, with maximums correlated to peak hours of urban activity. The spatial distribution revealed a direct influence of population density on the QAH, with densely populated areas exhibiting maximum magnitudes of 35 W/m2. Later, the direct effects of QAH on extreme events were explored, using simulations in scenarios with (URBAH) and without QAH (URB). QAH was found to contribute to significant increases in temperature, impacting the surface energy balance and resulting in greater cloud cover. Although the occurrence of extreme precipitation is sensitive to QAH, it is not determinant, highlighting the complexity of these interactions. The presence of QAH directly modulates precipitation, influencing the height of the atmospheric boundary layer (CLA), emerging as a crucial factor in cloud formation and precipitation intensity. These studies advance the understanding of the complex mechanisms linking urbanization, anthropogenic heat and climate extremes in Manaus. Continuous improvement of this research is vital to address emerging climate challenges in tropical urban environments, contributing significantly to the understanding and mitigation of QAH impacts in the Amazon region.