O impacto da presença de rios e área urbana no desenvolvimento de um sistema meteorológico de meso escala na Amazônia Central

Abstract

The impact of urbanization on mesoscale meteorological phenomena has been a focus from various researches. These have shown that urban areas change the spatial pattern rainfall, and life cycle of the meteorological phenomenon. In the Amazon, large Cities are typically bordered by rivers and areas of dense forest, which influence and are influenced by mesoscale convective systems. Studies of how these large cities, rivers and dense forest, impact the mesoscale phenomena have not yet been explored. In this work, numerical experiments were performed to evaluate the effect of the presence of rivers, forests and cities, as well as experiments to assess the impact of the horizontal growth of the city at the crossing of a squall line(SL). The results show the convective maximums of the SL are intensified in the passage about the city. On the other hand, without city, a SL entrance during its passage, intensifying again after leaving the city. The absence of the river produced a more early in the city and peaked after through the city. These experimental experiments that are not just the urban effect are responsible intensification of the SL over a city, and that co-dependence with the river influences a distribution and amount of rain. Already with urban expansion there is reduction of cloudiness over a city, which increases the surface pollution balance and changes the patterns of power partitioning. Positive thermal anomaly, imposed by the expansion of the city It is transported to higher levels of the atmosphere and current below the city. This one process, induces or weakens convective activities on the urban surface leading to reduced accumulation of rain. The combination of impacts caused by urban sprawl, adds to the diversity of the different types of surface coverage, in changing local circulations. This change shifts convective activity to far away from the urbanization area in a fast growing city scenario. The effect thermal growth of the urban area also adds to the mechanical effect that leads to formation of an obstruction zone, which makes it difficult to maintain convective systems about the city. In addition, rivers impact or propagation direction of SL after the passage about the city. These results contribute to the understanding of the role of rivers and cities about the development of a SL in the Central Amazon, and shows the refinement of tiles in numerical experiments are fundamental for the representation of interactions between the system and the surface.