The South American water balance: the influence of low-level jets

A climate study conducted from 1979 to 2008 analyzed the water balance in the Amazon and La Plata basin (LPB), focusing on the role of low-level jets (LLJs) as modulators of precipitation and moisture transport.

• Between 1979 and 2008, the Amazon basin and the La Plata basin (LPB) generally acted as moisture sinks (where evapotranspiration was less than precipitation), with moisture convergence accounting for approximately 62% of precipitation in the Amazon and 43% in the LPB.
• Low-level jets (LLJs) occurred on 884 days during the study period, most frequently during winter and between 0000 and 0600 UTC. During these LLJ events, the Amazon basin functions as a moisture source, particularly in the dry season, while the LPB remains a moisture sink throughout all months.
• LLJs significantly modulate precipitation in the La Plata basin, with precipitation levels being 32% higher during LLJ events than on days without them. This indicates that the moisture convergence trough of LLJs is critical for the LPB's water balance, whereas evapotranspiration is the more dominant variable for the Amazon basin regardless of LLJ presence.

APA

Inter-American Institute for Global Change Research (2025). The South American water balance: the influence of low-level jets. https://iai.int/es/pub_acad/the-south-american-water-balance-the-influence-of-low-level-jets/

Chicago

Inter-American Institute for Global Change Research. The South American water balance: the influence of low-level jets. 2025. https://iai.int/es/pub_acad/the-south-american-water-balance-the-influence-of-low-level-jets/.

Wikipedia

{{cite report |author=Inter-American Institute for Global Change Research |title=The South American water balance: the influence of low-level jets |date=15 January 2025 |url=https://iai.int/es/pub_acad/the-south-american-water-balance-the-influence-of-low-level-jets/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{interamericaninstituteforglobalchangeresearch2025south, author = {{Inter-American Institute for Global Change Research}}, title = {{The South American water balance: the influence of low-level jets}}, institution = {Inter-American Institute for Global Change Research}, year = {2025}, month = jan, url = {https://iai.int/es/pub_acad/the-south-american-water-balance-the-influence-of-low-level-jets/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }