The European Commission’s Joint Research Centre together with the World Meteorological Organization, CEMADEN, and SISSA recently published an overview of the persistent and extreme drought event in La Plata Basin (LPB), the second largest river basin in South America, which started around 2019 and is still ongoing today.
The drought has caused a water crisis in the area.
The findings of this study offer an in-depth understanding of how such a long-term disaster affects communities, economies, and ecosystems raising awareness about the need for developing preventive and mitigating measures against similar occurrences, possibly linked to climate change and mismanagement in some sectors.
Causes of the drought
A series of factors led to changes in the quantity and quality of the waters of rivers in La Plata Basin, among which the ones related to climate variability and change (with recurrent droughts and/or floods) are the most important ones.
Other changes with a strong impact where those related to land use; population growth; urbanisation; agricultural, industrial, and infrastructure development.
Therefore, understanding the impacts of current and recent past climatic and environmental conditions, and assessing future scenarios (including, e.g., an increased frequency and intensity of drought events) is crucial to support governmental policies and decisions, as well as to foster progress towards sustainable low-carbon economies, high resilience and more equitable societies in this region.
Impacts of the drought
The ongoing drought in the LPB has already caused considerable negative impact on natural ecosystems and important sectors of society. This includes:
- Loss of habitat, soil structure and erosion, organic soil oxidation and carbon release into the atmosphere in the wetlands area
- Fires caused by the great amount of dry biomass in the soil. The number of fires increased by 233% in 2020 and, e.g., the burnt area increased by 376% in the Brazilian Pantanal.
- Agriculture, e.g. the Grain Exchange (Bolsa de Cereales) of Buenos Aires (Argentina) stated that the production of soybean in the 2020-21 cropping cycle was about 3 million tons below forecasts, and nationally averaged soybean yields for Argentina were about 10% lower than the 2019-2020 cycle.
- Fisheries: Imposed severe fishing restrictions to protect stocks. The export quotas for freshwater fish were reduced to one third of the ones allowed in 2019.
- Waterway transportation, the lost freight capacity on water implying in turn higher costs per load
- Hydroelectricity generation: Hydro dams have reported the lowest water inflows in more than 90 years, pushing up electricity prices and boosting inflation rates
- Water supply for human consumption, human health: in the second part of September 2021, more than 20% of population in Argentina, Bolivia, Brasilia and Paraguay have been exposed to low, medium, and high drought risk.
Thanks to a close cooperation among JRC, WMO, CEMADEN, and SISSA, the report provides a complete overview of the persistent LPB drought and its impacts. It also stresses how drought should be considered a trans-regional, in some cases global, multi-sectoral threat.
As such, concerted actions are required to prevent and mitigate impacts. Local, European, and international partnerships are therefore needed together with harmonised national, regional, and global climate services on drought, such as the Global Drought Observatory.
To promote such an approach at the European level, in the framework of the new EU Strategy on Adaptation to Climate Change, the European Commission has recently launched the European Drought Observatory for Resilience and Adaptation (EDORA) project.
- 5 november 2021