Abstract: The main causes of changes in the composition of the Amazonian atmosphere are the fires during the dry season. In the rainy season, a city in Manaus presents itself as an important factor in the contribution of air pollutants and the production of organic aerosols. Aerosols originating in urban regions can conduct at all scales not only the radiative balance of the atmosphere and the climate, but also the chemistry of the atmosphere, the visibility, and the health of people exposed to high boarding rates. In this sense, the objective of this work was to evaluate an event of impact of urban influence on meteorological and chemical chemistry components of the atmosphere over the central region of the Amazon through the high resolution WRF-Chem model, during the period from March 10 to 13 de 2014. The simulated and observed data were obtained from the Applied Physics Laboratory of the University of São Paulo (LFA / USP). The dexterity of the model was assessed through the observed data from the GoAmazon2014 / 2015 experiment (meteorological variables and compounds) and Ceilometer and Lidar (Limit Layer Height). In general, the WRF-Chem model represents the coherent form of the day and night cycles of both meteorological and defined variables, when compared to the observed data, but with some limitations to capture some peaks with maximum values and data. The extended statistical analyzes that the lower skills (BIAS and RMSE) of the model, for the whole period of analysis (10-13 / 03), were for the variables of temperature at 2m and wind speed in 10m (values below 2.5), although the variable related to 2m also showed low skill. The components of simulated gases, both primary (carbon monoxide CO) and secondary (ozone O3), satisfactory results in representing the evolution of the day and night cycle, demonstrating a good performance of the simulation in representing chemical mechanisms as well as the transport dynamics of gases within the boundary layer.

Keywords: Urban area, aerosols, rainforest, GOAmazon2014/15, WRF-Chem