Dry and Wet Climate Periods over Eastern South America: Identification and Characterization through the SPEI Index

A large part of the population and economic activities South America are located in eastern regions continent, where extreme climate events a recurrent phenomenon. This study identifies characterizes dry wet periods at domain-scale occurring over (ESA) during 1980–2018 through multi-scalar Standardized Precipitation–Evapotranspiration Index (SPEI). For this study, spatial extent ESA was defined according to Lagrangian approach for moisture analysis. It consists major continental sink transported from Atlantic Ocean throughout year, comprising Amazonia, central Brazil, southeastern areas. The SPEI 1, 3, 6, 12 months accumulation calculated using monthly precipitation potential evapotranspiration time series averaged on ESA. analysis followed two different approaches: classification values as mild, moderate, severe, extreme; computation their respective parameters (duration, severity, intensity, peak). results indicate that prevailed 1990s 2000s, while conditions predominated 2010s, when longest more severe have been identified four scales.