The country lost 400,000 hectares of aquatic surface from 2023 to last year, according to the latest figures from the MapBiomas monitoring platform -- an area roughly the size of the US state of Rhode Island.

In the past 16 years, only 2022 showed an increase, and since 1985, the country has lost about 2.4 million hectares of river and lake surface due to drought, urban development, and over-pumping of aquifers.

"The dynamics of land occupation and use, along with extreme climate events caused by global warming, are making Brazil drier," said Juliano Schirmbeck, coordinator of the MapBiomas Agua report issued ahead of World Water Day.

"These data serve as an alert on the need for adaptive water management strategies and public policies that reverse this trend," he added in the report.

Brazil will host the COP30 UN climate conference in November in Belem, capital of the Amazonian state of Para.

Almost two-thirds of Brazil's surface water is found in the Amazon, which absorbs planet-warming carbon dioxide and plays a crucial role in climate regulation.

Last year, surface water expanse in the Amazon shrunk by 4.5 million hectares compared to 2022 -- an area the size of Denmark, said the report.

The Pantanal wetlands -- ravaged by drought and wildfires last year -- was the most affected biome with water surface in 2024 about 61 percent below the average measured since 1985.

While human-made water bodies such as reservoirs and dams expanded by 54 percent since 1985, this did not compensate for the loss of natural freshwater sources, the report said.