Amazon drought causes fires and kills dolphins

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A view of an area affected by severe drought in Rio Negro, Amazonas state, Brazil, on October 28. (Andre Coelho/EPA-EFE/Shutterstock)

The Amazon – a lush tropical basin that contains the world’s largest river, rainforest and one-fifth of its fresh water – is drying up.

The region is in its fifth month of drought, which is particularly damaging to the northern edge of the rainforest around the city of Manaus. The Rio Negro, a tributary in the northern Amazon, dropped to its lowest level on record last month. Wildfires are progressing in areas where waterways have receded.

“We’ve seen the effects of drought and fires before, but we’ve never seen so many wildfires happening so close to Manaus. Manaus hasn’t been that flammable in the past, or This is an area that was not considered flammable at all,” employee Paulo Brando said. Professor at Yale School of the Environment.

The effects of drought are having a ripple effect on forests. Travel and commerce along river systems has slowed significantly. Brazil has closed its fourth largest hydroelectric power plant. Drinking water is rationed in cities and towns along the river. Key fish species are struggling to spawn, threatening local food supplies, and endangered pink dolphins are washing up dead on riverbanks.

“I never thought I’d see the bottom of this river that I’ve been crossing every day for 14 years, and now I’m here looking at the bottom,” said Tasiana Coutinho. Her boat commute is now twice as long as before. Amazon has declined.

The rainy season has returned and river levels are starting to recover. But scientists predict below-average rainfall could make the region vulnerable again next year.

This year’s disaster follows devastating droughts in 2005, 2010, 2015, 2016 and 2020. The successive blows, combined with ongoing deforestation and rising temperatures, are chipping away at the Amazon’s resilience, bringing it closer to a tipping point. Rainforests could permanently turn into savannahs.

“Forests are recovering from one drought, and while they’re recovering, they’re vulnerable to another,” said Chris Boulton, a researcher at the University of Exeter’s Institute for Global Systems Research and lead author of a 2022 study on tipping points in the Amazon. There is a possibility of being attacked.” “If that happens, it will take longer to get back to normal, and it may eventually reach a point where it can’t return to normal.”

Degradation of the Amazon will have a major impact on the world’s climate. Ancient forests store 123 billion tons of carbon, more than three times the amount of carbon emitted by humans last year, and its pristine western regions emit millions of tons of carbon each year. It is extracted from the atmosphere. But wildfires and deforestation have turned the eastern edge of the forest into a net carbon emitter.

The rest of the forest may face the same fate.

“The global implications are very, very, very dangerous,” said Carlos Noble, an Earth system scientist at the Institute for Advanced Study at the University of São Paulo. “The fact that forests are losing more carbon than they are absorbing from the atmosphere shows we are on the edge of this tipping point.”

Rainforest on the brink

This year’s drought is Strong El Niño. Weather patterns that often result in drier conditions in the Amazon. Rising temperatures due to anthropogenic climate change are likely accelerating the evaporation of water from the earth’s surface, intensifying droughts. In Brazil, summer and autumn temperatures have risen rapidly in recent decades, and the average precipitation across the country has decreased. plummeting.

Drought conditions in the rainforest region have reached their most extreme levels in the past three months.

In the past, large-scale droughts rarely hit the Amazon. According to Nobre, this happens about once every 20 years. However, due to climate change, they are becoming more frequent visitors. “Unfortunately, over the past 20 years, this is becoming a two-in-a-decade strong drought,” he says. “It has a lot to do with global warming.”

Deforestation can also make conditions even drier and worsen droughts.

Because the Amazon is so vast, the Amazon itself produces rain. Moist air from the Atlantic Ocean moves over land, causing rain near the coast and watering the edges of forests. Dense clumps of vegetation release moisture into the air through a process called evapotranspiration.as Moist air blows deep inland, It will rain more. This process is repeated throughout the forest.

“The forest just needs to be there for that process to happen,” Boulton said. “When deforestation occurs at the edge of a forest where rain falls, the ability of the forest to recycle water internally is lost.”

Simone Asaid, an environmental anthropologist at Florida International University, said an environmental tipping point that could change the landscape of the Amazon Basin could also trigger a social tipping point that could change the lives of local people. Ta.

“Human populations can also pass through these thresholds,” she said. “They may end up in this poverty state, and because they are facing successive disasters, they may not be able to recover to what they were before in terms of income and quality of life.”

But Aseid and Boulton both emphasized that such a tipping point is avoidable. Deforestation, the main cause of the crisis, accelerated under the pro-development government of Brazilian President Jair Bolsonaro, but slowed during the early years of President Luiz Inacio Lula da Silva’s administration.

“Our projections today allow us to model the climate very well,” Boulton said. “But it doesn’t always model human interactions very well.”

Every day for the past 14 years, Coutinho has commuted by motorboat from his home in the Brazilian border town of Tabatinga to the Federal University of Amazonas in Benjamin Constant, down the Solimões River (the name of Brazil’s northern tributary). Amazon.

The trip is typically a 30-minute jaunt across water about 40 feet deep and a mile wide, a busy area filled with boats carrying children to school and merchants carrying goods.

Professor Coutinho from the Institute of Natural Culture said: “Rivers are part of life for all of us in the Amazon.” “Everything that comes to my city, everything that comes to my house, everything that comes to the houses of all my neighbors depends on the river.”

But over the past five months, the river has been transformed by the drought. The water level dropped to about a foot, and the Amazon and its tributaries were closed by sandbars. River traffic has decreased. Coutinho’s commute to work now takes more than an hour. She said captains are monitoring the pink river dolphin and guiding it into deeper, navigable waterways.

In October, at the height of the dry season, Tabatinga’s water level gauge was placed on a dry riverbank. Normally the water depth is 10 feet this time of year, but the reading on October 16th was -2.5 feet. This means that the water has retreated to a shallow stream in the middle of the riverbed. 1.5 feet below the zero mark on the water level gauge.

“The world is looking to Amazon to be the solution to their problems,” she says. “But we have a problem to solve.”





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