Drought in the Amazon: worsening of the crisis in recent times
Matilde de Souza e Victor de Matos Nascimento
Abstract: This article discusses how extreme drought events in the Amazon have become more frequent. We highlight the impact of deforestation and climate change in the region and how this worsens water, food, and energy insecurity for millions of people.
“For eight years, we supplied the world with wood. Convinced that there were no problems, we accepted that they would sell pieces of the Amazon. Small snippets, they said. Areas chosen by scientists so that the ecosystems would not be altered”. Published in the early 1980s, the dystopian novel And Still the Earth, written by Ignácio de Loyola Brandão (1981, p. 107, our translations), pointed to a tragic scenario. In the same paragraph, the author continues: “[u]ntil, one day, the photos taken by satellites revealed the devastation. The entire forest core was irreparably decimated. The rest did not last long; in a few years, the desert took over.”
In recent times, the Amazon basin has experienced more frequent extreme drought events. There are records of severe droughts in 2005, 2010 and 2016. For Marengo et al. (2008), the 2005 drought would have been one of the most intense since 100 years, especially in the southwest of the Amazon, a phenomenon related to the atypical warming of the North Atlantic. However, in 2011, the same author led the writing of another article in which he analyzed the 2010 drought, considering it worse than that of 2005 and which affected 70% of the basin mentioned above (Marengo et al., 2011). The 2015 drought, although less studied, was also significant, with a greater precipitation deficit in some regions compared to previous events (Panisset et al., 2018).
The phenomenon has worsened in the current decade: droughts are more severe and occur at increasingly shorter intervals. This problem intensifies the environmental and climate challenges already posed to the region. In 2020 and 2021, the phenomenon followed a pattern already observed, although aggravated by climate variability and changes in the surface temperatures of the Atlantic and Pacific oceans. These interrupted the region’s normal hydrological cycle, reducing the volume of precipitation and causing conditions conducive to widespread drought (Paredes-Trejo et al., 2022).
Previous research has already indicated the causes of severe and more frequent droughts. Marengo and Espinoza (2016) recognized drought as a natural phenomenon in the Amazon region but indicated that the most likely causes for its more rigorous and frequent occurrence would be climate phenomena such as El Niño and La Niña; sea surface temperature anomalies in the tropical Atlantic; variability in precipitation and moisture flows, which modify the region’s water regime; changes in the flow of moisture out of the Amazon, particularly in the rainy season, which can worsen droughts; anthropogenic climate change. These events impact the forest, reducing its carbon absorption capacity (Buriti & Barbosa, 2022).
The cumulative effect of such recurrent severe droughts is the decline in land productivity, particularly in the southwestern region of the basin, which has suffered more significant degradation driven by two combined factors — prolonged drought conditions and deforestation. This problem has local implications with broader effects on global climate regulation, given the critical role of the Amazon region in carbon sequestration (Cui et al., 2022). The 2023 drought further aggravated these conditions.
Regarding this 2023 event, Marengo and Costa (2023) published a statement in which they stated that the cause of the drought was an important reduction in rainfall, in addition to four heat waves that occurred during the period before the rainy season, added to a longer winter warm due to El Niño. Together, these factors led to a drop in water levels in several regional rivers, the lowest since 1902. In the authors’ assessment, the immediate consequences were deaths of fish and aquatic mammals, scarcity of drinking water and food for riverside communities, interruption of river transport and increased risk of waterborne diseases, significant loss of tree foliage, increasing vulnerability to forest fires.
We see the scenario outlined by Loyola Brandão taking shape based on projections made by Marengo and Costa (2023): they predict medium and long-term impacts such as forest degradation, increased tree mortality, and reduction of carbon sinks, local socio-environmental impacts, reduction in the transport of atmospheric moisture to the south of South America, with repercussions on water and energy security. Energy security was compromised during the 2023 drought, as it affected electricity production mainly in Ecuador and the Brazilian state of Rondônia, with energy rationing.
The authors present some predictions: the drought in 2024 may continue, intensified by El Niño and the warming of the Tropical North Atlantic; the possibility of a “new normal” for the Amazon if effective measures are not taken to mitigate climate change. They reinforce solutions that are already known, although not necessarily practiced: zero deforestation policies and conservation of Amazonian ecosystems, emergency plans to guarantee the supply of water, energy, transport, and health to affected populations, and compliance with the goals of the Paris Agreement to limit the increase in global temperatures.
More severe and frequent droughts significantly affect ecosystems, including increased wildfires, tree mortality, and altered carbon flows. These events also impact local populations, causing economic losses, health damage, and disasters (Marengo & Espinoza, 2016). This understanding is shared by Lovejoy and Nobre (2019), who state that there are real and increasing risks of the region reaching a point of no return. The authors highlight deforestation and environmental degradation as critical factors accelerating the reaching of this tipping point, with global climate repercussions including changes in rainfall patterns and an increase in extreme weather events that could result in the loss of the Amazon rainforest. Such an event, if it were to occur, would have catastrophic consequences such as the mass extinction of species and loss of vital ecosystem services such as the regulation of the hydrological cycle, in addition to implications for Indigenous peoples and riverside communities, whose livelihoods are directly linked to the forest integrity.
The intense sequence of severe droughts in the Amazon aggravates concerns, especially among scientists, regarding the region’s vulnerability to extreme weather conditions. The impacts of this sequence of events are profound and multifaceted, as already indicated above. Considering the dimensions of water, energy, and food security, the consequences of these events are worrying. Nobre et al. (2016) have already shown that deforestation and climate change could produce a savannization effect in the Amazon. As highlighted above, the results of such a situation would be irreversible, with harmful effects on biodiversity. In this condition, the economic effects would harm the local population, primarily indigenous peoples and traditional communities.
Considering the region’s water, energy, and food security, these events have serious consequences that affect the Amazon ecosystem, the regional economy, and human populations that depend on local natural resources. In this sense, some of the main effects of these events are compromising water security, given that severe droughts dramatically reduce the volume of water in rivers, affect the riverside population in terms of access to water for consumption, and compromise their primary means of transport (Marengo et al., 2011); impact on energy security, also compromised by droughts that reduce the volume of water in reservoirs, limiting the capacity to generate energy, a phenomenon already recorded in the 2005 drought (Frappart et al., 2012) and which is getting worse; Effects on food security are also evident, since agriculture, especially that developed on small properties and which depend on the regularity of the rainfall regime, is severely harmed. Prolonged droughts in the region make subsistence agriculture difficult and lead to essential losses in food production, with consequences for local supplies (Jimenez et al., 2019).
Scholars indicate a feedback process in this process: deforestation intensifies the phenomenon of droughts since the reduction in forest cover reduces atmospheric humidity which, in turn, worsens the intensity of dry seasons. This process generates a vicious cycle: more intense droughts increase deforestation, which, in turn, increases the severity of future droughts (Staal et al., 2020).
Conclusion
The increasing frequency, intensity, and severity of droughts in the Amazon basin, as observed since the early 2000s, highlights the fragility of this vital ecosystem in the face of climate change. Even considering that droughts are components of the natural cycle of this ecosystem, anthropogenic climate changes, including deforestation and global warming, have exacerbated their impact. As this article illustrates, the consequences are severe at local, regional, and global levels, putting biodiversity at risk and threatening the livelihoods of local communities. Furthermore, environmental degradation has far-reaching implications for water, energy, and food security. Without immediate and concerted efforts to mitigate these trends, including halting deforestation and adhering to global climate agreements, the Amazon risks reaching a critical tipping point. If this condition occurs, the savannization of the forest will compromise the service it provides as a carbon sink, the environmental and socioeconomic consequences will be devastating, and, given the studies and projections, they will extend beyond regional limits, impacting climate regulation globally. Thus, addressing the Amazon drought crisis requires urgent and sustainable policy actions at local and international levels.
References
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About the Authors
Matilde de Souza: Professor of the Postgraduate Program and the Department of International Relations at PUC Minas. Contact: matilde@pucminas.br.
Victor de Matos Nascimento: PhD Student at the International Relations Postgraduate Program at PUC Minas. Contact: victormatosnasc@gmail.com.
