Effects on urbanization on a WRF-simulated heavy precipitation over the Maceió city

Land use in the city of Maceió is rapidly changing from its natural state to accommodate a growing population and tourism. These changes include increased urbanization. There has been a significant increase in the frequency and intensity of extreme events occurring in recent years in the Northeast region of Brazil (NEB), especially in its metropolitan areas. It is believed that this may be associated with the exacerbated land use (LU) in these areas. Therefore, the objective of this work is to evaluate how an intense simulation event using the WRF model would be affected if the size of the Maceió metropolitan region were increased. Furthermore, the study will investigate the effects that the LU has on the intensity of this extreme event and its structure. To achieve this, the land use around the metropolitan region of Maceió was changed to a slightly larger urban area in the input files and then re-executed under the same parameters. Control and experimental simulation were compared using vertical profiles, flow fields and instability indices. The heavy rains that occurred on March 17, 2020 over Maceió were caused by an intense confluence of air at low levels (1000 hPa) observed on the state's coast in the early hours of the day. This conference occurred due to a small low pressure center that was present near the coast of Bahia, which could also be observed in the Sea Level Pressure field. The Convective Available Potential Energy (CAPE) field also indicated intense instability over the region, with values above 1000 J/Kg after 16 UTC over a large part of the north/east sector of Alagoas. Skew T Log-P thermodynamic profiles demonstrated high levels of instability throughout the 17th, gaining more strength between 16-21 UTC, with a maximum CAPE of 1864 J/Kg at 18 UTC. Throughboth simulations, it was reported that in the LU experiment there was an increase in the intensity and spatial distribution of the occurrence over the city of Maceió, as well as being associated with an increase in instability. Impacts were also identified on sensible and latent heat fluxes, and vertical shear. These results, despite being initial, show that there is a sensitivity in the use of land in convection and, consequently, in the intensity of learning.