Eventos extremos de precipitação diária e desastres socioambientais nas capitais dos estados da costa leste do Nordeste do Brasil.

Abstract

The objective of this study was to analyze the extreme events of daily rainfall, as well as its possible contribution to the occurrence of socio-environmental disasters in the state capitals of the east coast of northeastern Brazil. For this, daily precipitation data were used, for the period 1986 to 2020, provided by INMET, as well as data from alerts issued by CEMADEN, for the period 2016 to 2020, provided by CEMADEN. Climatological Standards, provided by INMET, for the periods 1961 to 1990 and 1981 to 2010 were used to verify the behavior of precipitation in the study area. Reanalysis data, from ECMWF, and images from the GOES and METEOSAT satellites were used to analyze the atmospheric conditions associated with the occurrence of extreme precipitation. The Extreme Value Theory was used to model the maximum precipitation, from the Generalized Extreme Value distribution, as well as to obtain the return period for the extreme precipitation in the NEB east coast. From the results obtained, it was verified that precipitation ≥ 200 mm/day occurred in Natal – RN, Recife – PE and Salvador – BA. Natal – RN is the location that presents the most records of precipitation ≥ 200 mm/day, and the location that presents the maximum daily precipitation, of the entire time series. It is expected that at least once every two years, extreme daily precipitation events, between 90.62 and 123.61 mm, will occur for the study region. For 5, 10 and 25 years, at least one event is expected to occur between 118.59 and 155.49 mm; 133.31 and 184.68 mm; 148.47 and 237.32 mm, respectively, in NEB's east coast capitals. Salvador – BA

and Aracaju – SE have the highest and lowest number of occurrences of socio- environmental disasters. Landslides and floods are the most recorded typologies for the

study area. The extreme events analyzed were influenced by the position of the South Atlantic Subtropical High, as well as by the presence of high and low pressure systems in areas over the continent and/or adjacent Atlantic Ocean, thus contributing to the transport of moisture from the Atlantic Ocean to the coast of the Brazilian Northeast.