Moisture Transport during Anomalous Climate Events in the La Plata Basin

• Published in: Atmosphere
• Main Authors: Anita Drumond, Marina de Oliveira, Michelle Simões Reboita, Milica Stojanovic, Ana Maria Pereira Nunes, Rosmeri Porfírio da Rocha
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2024
• Subjects: extreme climate events; SPEI; Lagrangian method; La Plata Basin; atmospheric moisture; Meteorology. Climatology; QC851-999; North Atlantic
• Online Access: https://doi.org/10.3390/atmos15080876; https://doaj.org/article/9455e9352b9e46e29cfb14a7881bee66

This paper examines the linear relationship between climate events in the La Plata Basin (LP) from 1980 to 2018 and atmospheric moisture transport from major sources using a Lagrangian approach. The standardized precipitation evapotranspiration index (SPEI-1) was utilized to assess climate events, as monthly water balance variations may be related to changes in atmospheric moisture transport. A total of 49 dry and 46 wet events were identified through sequences of negative and positive SPEI-1 values, respectively. Lagrangian analysis tracked changes in moisture uptake and supply from sources to the LP during these events. Simple linear regression analysis revealed a relationship between moisture transport from the Amazonas (AM), North Atlantic (NA), and Tocantins (TO) basins and the severity and duration of climate events. Increased moisture supply from the São Francisco basin (SF) and Eastern Brazil oceanic (EBO) sources intensified the duration and severity of wet events. Peak wet events were linked to increased moisture supply from the northern South America basins (AM, NA, and TO), while peak droughts were related to decreased moisture uptake from eastern sources (TO, SF, and EBO). Our findings highlight how the water balance in distant regions affects the LP via moisture transport, emphasizing the need for interconnected adaptive strategies.