South America: Surpluses emerge in the Amazon Rainforest

21 April 2025

THE BIG PICTURE

The forecast for the 12-month period ending in December 2025 indicates that widespread exceptional deficits will diminish in portions of Brazil, the Southern Cone, and Bolivarian Nations, though some regions of northern, central, eastern, and southern Brazil will observe continued anomalies. Surpluses are expected to arise in portions of the Bolivarian Nations and the Amazon Rainforest.

Severe to exceptional deficits are expected in:

Central and southern Brazil, with exceptional deficits spreading primarily through the states of Rondonia, Mato Grosso, Mato Grosso do Sul, southern Goias, and western Sao Paulo.
Eastern Brazil, in the states of Bahia, Piaui, and Tocantins.
Northern Brazil, in western Roraima, northern Para, and Amapa. These anomalies continue north into much of eastern Venezuela and in the Guianas, specifically in southern Suriname and southern French Guiana.
Central Paraguay, in regions north of the city of Asunción.
Argentina, within the Santa Fe province, and northern Chile, within the Tarapacá region.

Severe to extreme surpluses are anticipated in:

Western Brazil, in central and southwestern areas of Amazonas.
Portions of the Bolivarian Nations, with the most intense anomalies occurring in central Ecuador, southeastern Colombia, western to southeastern Peru, and areas near the western border of Bolivia.
Argentina, within the Buenos Aires province, with anomalies continuing west into the La Pampa province.

Transitional conditions are forecast in:

Northern Brazil, in the state of Amapa, as well as northern coastal Para.
Areas of the Guianas, specifically in southeastern Suriname and central French Guiana.

The 3-month maps (below) show the evolving conditions in more detail.

FORECAST BREAKDOWN
The forecast through June 2025 indicates that severe to exceptional surpluses will be present in western Brazil, within the state of Amazonas. Further west, severe to exceptional surpluses will also spread further throughout western coastal Colombia, central Ecuador, and northern to southeastern Peru. Surpluses are also expected to emerge in Argentina’s Buenos Aires province. Exceptional deficits will continue in central and southern Brazil, lingering in Rondonia, Mato Grosso, Mato Grosso do Sul, and Goias. Further north, the state of Amapa will observe widespread exceptional deficits, which spread further west into the Guianas. Northern Argentina will observe severe deficits, in areas north of the city of Cordoba.

From July through September 2025, exceptional deficits in central and southern Brazil are expected to continue. Further north, exceptional deficits will spread further throughout the Guianas, as well as northern coastal regions of the state of Amapa and eastern Venezuela. Severe to extreme deficits are forecast to spread throughout northern and southwestern Colombia, as well as western portions of Venezuela. Areas near the northern Colombian city of Barranquilla will observe exceptional deficits. Severe to extreme surplus will continue in Brazil’s Amazonas region, as well as southern areas of Peru and western to southwestern Bolivia. Surpluses in the Buenos Aires province of Argentina will persist.

The forecast for the final months – October through December 2025 – indicates that most exceptional deficits in Brazil will resolve, though some anomalies will continue in the northern coastal regions of Para and Maranhao. Exceptional deficits will also remain in some portions of Guyana and Venezuela. Moderate to severe surplus may spread further throughout central and northern Argentina, as well as small portions of western and southern Bolivia.

Please note that WSIM forecast skill declines with longer lead times.

IMPACTS
In southern Brazil, museums are still recovering from floods which affected the region in April and May 2024, which caused almost $15.4 billion in damages and caused almost 200 deaths. Events such as the Mercosul Biennial in Porto Alegre were postponed, now scheduled to occur in March to June 2025, in an attempt to help revitalize the region’s art and tourism sectors. Several museums, such as the Museu Histórico Visconde de São Leopoldo and the Museu de Arte Contemporânea do Rio Grande do Sul, suffered significant damage and losses, while others, like Fundação Iberê Camargo, were spared, but still saw a decrease in attendance.

Severe flooding recently hit Bolivia’s Beni region, submerging grasslands and agricultural fields, as well as causing 55 deaths. These floods caused displacement of families and threatened livestock, with nearly 200,000 cattle at risk. Exports of soy and beef were disrupted and local food prices increased as a result of the flood.

A recent study attributed the risk of increased drought in Amazonian ecosystems to global warming, with drought potentially affecting 33% of frog, toad, and treefrog habitats in the Amazon and Atlantic Forest. The Atlantic Forest hosts over 700 species – over 50% of which are not found anywhere else on Earth. Amphibians rely on water to survive, and can die within hours without moisture.

NOTE ON ADMINISTRATIVE BOUNDARIES
There are numerous regions around the world where country borders are contested. ISciences depicts country boundaries on these maps solely to provide some geographic context. The boundaries are nominal, not legal, descriptions of each entity. The use of these boundaries does not imply any judgement on the legal status of any territory, or any endorsement or acceptance of disputed boundaries on the part of ISciences or our data providers.

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