ANÁLISE DA PRECIPITAÇÃO ANUAL E DA QUADRA CHUVOSA PARA O MUNICÍPIO DE SÃO LUÍS, MARANHÃO
DOI:
https://doi.org/10.22456/1982-0003.133034Abstract
Analyzing rainfall variability is essential for urban and environmental planning in municipalities and regions of Brazil. Thus, this study aimed to evaluate the variability of annual precipitation and the rainy season for the municipality of São Luís (MA). For this, monthly precipitation data of historical series from 1974 to 2022 obtained from the National Institute of Meteorology (INMET) database were used. Thus, the Rainfall Anomaly Index (RAI) technique developed by Roy (1965) and adapted by Freitas (2004; 2005) was applied to assess negative and positive rainfall anomalies in the Northeastern region of Brazil (NEB). The study showed that rainfall patterns in São Luís presented low variability on the annual scale; however, when analyzing RAI, it was possible to observe greater number of years with positive anomalies. Thus, the years 1974 and 1985 were classified as extremely rainy years, while the extremely dry class was verified only for 1983. Furthermore, in the analysis of the rainy period, March and April stood out with the highest amounts of negative anomalies, mainly the March. However, April presented 8 years with negative anomalies in the last 10 years, while February and May presented balance between positive and negative anomalies throughout the historical series.