Role of the Southern Annular Mode in the sea level over the southern Blue Amazon.

Abstract

Regional sea level rise varies from the global average and is influenced by climate variability. We studied sea level anomalies in southern Brazil from 1993 to 2022, finding increasing trend from 1993 to 2022. We used oceanic and atmospheric dynamics to understand the rapid sea level rise. Positive trends in the Southern Annular Mode and the South Atlantic Ocean subtropical gyre intensified wind stress curl and Ekman transport. If global warming continues and the Southern Annular Mode remains in a positive trend, sea level rise in southern Brazil is likely to persist and increase risks for the population in this low-lying coastal area.