The Amazon River Basin (ARB) has been experiencing a severe drought since mid-2023, attributed to low rainfall and unusually high temperatures throughout the year.
This drought is affecting the world’s largest rainforest, a critical area for biodiversity and a vital component of the global water and carbon cycles.
The river’s water levels have reportedly reached their lowest in 120 years, posing significant threats to the approximately 30 million people living in the Amazon basin across various countries, including Brazil, Peru, Colombia, Venezuela, Ecuador, and Bolivia.
This situation has disrupted transportation, and isolated communities, and resulted in wildlife fatalities.
The ARB’s extensive river system is crucial for the region’s energy supply, particularly hydropower. Brazil depends on hydropower for 80% of its electricity, followed by Colombia at 79%, Venezuela at 68%, Ecuador and Peru at 55%, and Bolivia at 32%, as per a 2018 report by USaids.
The ongoing drought is adversely affecting dam capacities and energy generation, leading to power outages in the region as early as June 2023.
International scientists from Brazil, the Netherlands, the UK, and the US, using established peer-reviewed methods, have been investigating the influence of climate change and the El Niño phenomenon on this drought.
El Niño is commonly associated with dry conditions in the Amazon. The entire basin has been facing severe or exceptional drought conditions in the latter half of the year.
Drought can be characterized in various ways. Meteorological drought is defined solely by low rainfall, while agricultural drought considers both rainfall and evapotranspiration. The latter, exacerbated by regional warming, significantly intensifies drought impacts.
This study assesses both agricultural and meteorological drought. Agricultural drought is gauged using the Standardised Precipitation Evapotranspiration Index (SPEI), which calculates water availability based on rainfall and potential evapotranspiration.
The lower the SPEI values, the more severe the drought. Meanwhile, meteorological drought is analyzed using the SPI index, which is based solely on precipitation.
