MapBiomas Water Platform Amazon Countries launched on Wednesday (20)

Amazonian countries are on the verge of a drastic change in their water surface, according to data obtained by new monitoring platform MapBiomas Water Amazon Countries, lançada nesta quarta-feira, dia 20.

The historical average water surface in this vast region for the period between 2000 and 2022 is 25.4 million hectares (Mha). But in the last decade, all the Amazon countries have seen a reduction in surface water. When comparing the average of the last decade with the historical average for the period, 1 million hectares of water surface were lost in the nine Amazonian countries. This is despite the gain of 747,000 ha (compared to the historical average) recorded in 2022, which brought the total water surface area to 26.2 Mha, representing 2% of the territory analyzed.

Brazil was largely responsible for this gain in 2022: 910,000 ha more water surface were identified last year compared to the historical average of 17.9 Mha of water surface. The 18.8 Mha recorded in 2022 in Brazil represent 72% of the total water surface of the Amazon countries. 

The gain in water surface area in Brazil in 2022 is more than four times the total water surface area in Ecuador last year (227,000 ha). On the other hand, Peru lost the most water surface in this period: 124,000 ha, a relative loss of 7% compared to its historical average (1.8 Mha). 

In general, however, the nine Amazonian countries have undergone a series of critical transformations in their water resources over the last two decades that have resulted in a general trend of shrinking water surface area. For Bolivia, Brazil, Colombia, Ecuador, Guyana, French Guiana, Peru, Suriname and Venezuela, the interval between 2013 and 2021 was identified as the period with the lowest water surface in the historical series analyzed. 

"In our region, there are three countries that have shown a reduction in their water surface over the entire period between 2000 and 2022: Ecuador, Peru and Bolivia. The other six countries showed a period of increase and another of decrease in water surface area in relation to the historical average, which occurred between 2013 and 2021, with similar trends, but of varying magnitude," says Eva Mollinedo, from the Fundación Amigos de la Naturaleza (FAN-Bolivia) and a member of the MapBiomas Water Amazonian Countries team.

>> Main highlights of water surface dynamics in Amazon countries (2000 to 2022)

The reduction in the water surface is also evident in a sustained trend of glacial melting which, between 1985 and 2022, led to the loss of an area of 184,000 hectares of glaciers, which is equivalent to 56% of the area detected in 1985. All Andean countries suffered glacier loss during this period. The greatest extent was in Peru, which lost 115,000 hectares; while Venezuela, the country with the least glacial coverage, suffered the greatest loss at 97% (82 hectares).

"This decrease could have an economic impact on the populations of the tropical Andes, with effects on agriculture, drinking water supplies and the integrity of ecosystems," according to Juliano Schirmbeck of Geokarten (Brazil) and a member of the MapBiomas Water Amazon Countries team. "Tropical glaciers have suffered losses in area in response to rising temperatures caused by accelerating global climate change. These tropical glaciers are considered a kind of 'thermometer' for the Earth, since their expansion or reduction is closely related to the global climate," he adds.

"All of this aggravates health problems and difficulties in accessing food, which is more damaging to populations with fewer economic resources. This decrease in water surface contributes to the proliferation of forest fires and greenhouse gas emissions, which affects both biodiversity and local communities," says Carlos Souza Jr., from Imazon-Brazil and a member of the MapBiomas Water Amazon Countries team.

About MapBiomas Water Amazon Countries

The MapBiomas Water Amazon Countries iniciative was developed collaboratively by civil society organizations in the region that have in-depth knowledge of the particularities of their respective countries: RAISG members in Brazil, Bolivia, Colombia, Ecuador, Peru and Venezuela. Data interpretation is carried out in a participatory manner, adjusting the methodology to arrive at a standardized product for the region. It is the first time that the coverage of water surface mapping has been expanded to cover all Amazonian countries.

The MapBiomas Water project has developed a series of maps that retrospectively document the water surface in the Amazon countries between 2000 and 2022. These maps use satellite images and machine learning techniques to identify water pixels with high precision. The use of advanced technology, such as Google Earth Engine, has enabled the creation of the first surface water dataset covering all Amazonian countries. Water detection is based on sub-pixel level classification methods, using fuzzy logic, decision trees and post-classification procedures. This monthly and annual data offers an unprecedented and detailed understanding of water dynamics in the region.