Análise geral de eventos extremos de precipitação em escala horária no Brasil: aspectos meteorológicos associados

Abstract

The climate variability in the territory of Brazil is characterized by the influence of various meteorological systems, ranging from local to global scales. Associated with this variability, there are observations of extreme precipitation events, which have been occurring more frequently due to climate change. However, meteorological databases for precipitation analyses have deficiencies, making the challenge of studying climatic aspects, especially those at subdaily and hourly scales, more demanding. Thus, the objective of the present study was to analyze the occurrence of Extreme Hourly Precipitation Events (EHEPE) across the entire national territory. Twelve years (01/01/2010 to 31/12/2021) of hourly precipitation data were collected from 423 automatic weather stations managed by the National Institute of Meteorology (INMET). It was found that the regions diverged significantly from each other, presenting distinct values of EHEPE occurrence. This divergence is due to the vast territorial expanse of Brazil, coupled with the predominance of different meteorological systems at play in the country. However, the average percentage of data gaps varies between 8.40% in the Southeast to 29.26% in the Northern region, indicating a high disparity in the number of gaps for each region, which could lead to errors in analyses conducted without caution. Thus, studying extreme events at an hourly scale in conjunction with missing values has proven to be highly significant for the topic.