Polski
Brazil is one of the areas hard hit by climate change. The northern part of the country is once again facing extreme drought. Historically, the phenomenon was relatively rare there, but in recent decades there has been an increase in the frequency and duration of rain-free periods. This year’s drought in the Amazon has reached record levels, wreaking great havoc on the Earth’s richest ecosystem.
Drought a major threat to Amazonians
Drought in the Amazon is having a huge impact not only on the environment, but also on the local population and economy. Falling water levels in rivers make water transportation difficult or completely impossible, limiting residents’ access to basic foodstuffs. Safety is also at risk – decomposing bodies of dead animals contaminate drinking water. Huge losses can also be spoken of in the context of fishing, which is the livelihood of many local communities.
Faced with such a dramatic natural disaster, the Brazilian government has declared a state of emergency for fifteen counties in the state of Amasonas in recent days, and recommended a state of readiness for forty more. A $20 million government program to counter the effects of the drought has also been launched. Transports with food, drinking water and medicines are being diverted to the areas most affected by the lack of rainfall. With the highly likely arrival of an El Niño compounding the drought, it is estimated that up to half a million residents could be affected by the end of the year.
Extinction of endemic dolphins in Lake Tefé
Drought in the Amazon affects all elements of the ecosystem, including aquatic species. Among them are freshwater dolphins endemic to the Amazon basin – Amazonian Sotalia(Sotalia fluviatilis) and Amazonian Inia(Inia geoffrensis). In recent days, not only hundreds of dead fish, but also the bodies of a hundred freshwater dolphins have been found at Lake Tefé, located in the northwestern part of the country. Scientists link their dying on such a scale to a period of drought and hot weather – the water temperature in the lake exceeded 39°C.
Dolphins feed on fish, and their mass die-offs are causing a drastic decrease in food availability. In addition, the reduced water level prevents the movement of these non-small animals. Over the past two weeks, the level of the Amazon has been dropping by 20-30 cm every day, and its depth, in relation to last year’s data from the same period, is more than 6 m lower.
Freshwater dolphins living in the Amazon basin are indicator organisms. The death of such a large number of individuals at one time may mean that water conditions have been severely disturbed. According to forecasts, the drought in the Amazon is expected to last for several more weeks. It is therefore highly likely that animal populations living in the area will suffer even more.
Drought in the Amazon – a dangerous paradox that could change the world
One of the first associations to the phrase “rainforest” is moisture. Drought, on the other hand, is associated with the desert. The phrase drought in the Amazon, therefore, raises a bit of a guffaw – this region, after all, is characterized by year-round, lush vegetation, intense rainfall and sultry air that smells of grass and soggy wood. Where, then, is there room for drought? Well, a tropical rainforest is a humid ecosystem that used to be haunted by drought infrequently, once every few decades. Nowadays, drought in the Amazon happens much more frequently, posing a major threat not only to the region, but to the entire world.
While the Amazon is considered to have the capacity to survive occasional hydro-meteorological extremes, the more frequent occurrence of anomalies in the precipitation regime in recent decades and the tragic consequences of prolonged droughts make it clear that this capacity is clearly limited.
More dry trees mean less carbon dioxide absorbed from the atmosphere
Rainforests play an extremely important role in maintaining the world’s climate balance by regulating the water cycle and absorbing huge amounts of carbon dioxide, which slows global warming. Long-term water deficits cause vegetation to wither. Droughts significantly reduce the absorption ofCO2, so it accumulates in the atmosphere. As the flora dies off, less water enters the atmosphere, so the amount of precipitation decreases. This drives a very dangerous feedback loop.
Felling and burning of trees drastically weakens the ecosystem
Drought in the Amazon is taking a greater toll on areas weakened by logging. Exposed parts of the forest are more exposed to hot air, exacerbating the drying out of vegetation in the border range. The stripped stems and trunks do not act as a barrier to the warm air, making it penetrate deeper, drying out more parts of the forest. Dry plant parts facilitate the spread of fire, leading to uncontrolled fires and the emission of large amounts ofCO2.
Drought in the Amazon – what’s next for the most complex ecosystem on Earth?
Neither the Amazon forests nor the people living there are prepared for such extreme conditions. And while infrequent naturally occurring droughts have not posed much of a threat to the rainforest, significantly increased long-term water deficits, amplified by anthropopressure, are leading to the degeneration of the Amazon rainforest. The threat is so great that it puts their continued existence in question.
According to a hypothesis considered highly likely, extreme droughts combined with increasing deforestation and associated fires will lead the Amazon’s forests to the so-called “drought”. critical point. This is the moment when irreversible changes occur, in which the death of the forest will occur faster than its restoration. The tropical thicket will begin to transform into a savannah-like ecosystem, with far-reaching consequences for the entire planet.
As vegetation dies and loses its absorption potential towards carbon dioxide, rainforests will become emitters of carbon dioxide, which will contribute to exacerbating climate change. Recent studies of the composition of the atmosphere over the Amazon have confirmed this conjecture – it is now clear that its southeastern part emits moreCO2 than it can absorb.
The current drought in the Amazon is described as unremarkable. The scarcity of water in the area has negative ecological, economic and social consequences not only for the region, but also for the whole world. If globalCO2 emissions are not curbed and climate change is halted, adverse phenomena such as drought will increase, so that rainforests could disappear from the world map forever.
