Severe drought grips the Amazon rainforest: The impact, cause and grim future

“We have never seen anything like this. It is the worst drought in history,” said Wilson Lima, who is the governor of Amazonas (a Brazilian state, covered almost entirely by the Amazon rainforest).

The latest calamity is another addition to the long list of causes that are accelerating the destruction of the Amazon, called the planet’s lungs. It covers nearly seven million square kilometres, or about the area of Australia, and stores more than 150 billion metric tonnes of carbon.

Stranded boats, wildfires, dead fish

The present spell of drought began in June and has stubbornly persisted since. As a result, water levels have dropped and high numbers of fish and river dolphins, known as boto, have been washing up dead — their rotting carcasses have contaminated the water supply in some areas, forcing residents to use it for cooking, bathing, and drinking.

Boats and houseboats are seen stranded at David’s Marina, as the water level at a major river port in Brazil’s Amazon rainforest hit its lowest point in at least 121 years on Monday, at the Rio Negro river in Manaus, Brazil October 16, 2023. (REUTERS/Bruno Kelly)

The lack of water has also stalled the operations of a major hydropower dam in the region and left tens of thousands of people stranded in remote jungle villages, with limited access to food, and other supplies. Brazilian authorities fear that about 500,000 people may be affected due to the drought by the end of October.

“There’s just dirt now where the river used to be,” Ruth Martins, 50, a leader of Boca do Mamirauá, a tiny riverside community in the Amazon, told The New York Times. “We’ve never lived through a drought like this.”

The extreme dry conditions have made the rainforest more vulnerable to wildfires too. So far this month, the Amazonas state has witnessed 2,700 blazes — the highest ever noted for the month of October since the records began 25 years ago, according to Brazil’s National Institute for Space Research.

Smoke from wildfires has plummeted air quality in Manaus, a city of two million in the middle of the Amazon, to hazardous levels. Children and older people living in the city are struggling to breathe and many have ended up in hospitals, according to doctors in Manaus.

Smoke from wildfires in the Amazon is seen in the port of Manaus, Brazil October 12, 2023. (REUTERS/Bruno Kelly)

The combined effect of El Nino and high sea surface temperatures

Droughts aren’t unheard of in the Amazon. Most recently, the rainforest witnessed a dry spell in 2021, which was the worst in at least 90 years. The latest drought, however, is probably even more severe as two simultaneous natural events have hindered cloud formation, further reducing the already low rainfall levels in the region.

One of them is the onset of El Nino, which refers to an abnormal warming of surface waters in the equatorial Pacific Ocean. The weather pattern is known to increase the likelihood of breaking temperature records and triggers more extreme heat in many parts of the world and in the ocean.

The other weather event is the unusually high water temperatures in the northern tropical Atlantic Ocean. Due to warmer ocean waters, heated air rises into the atmosphere, which then reaches the Amazon rainforest. The warm air inhibits the formation of clouds, causing rainfall to drop sharply.

A boy walks on a dry area of the Igarape do Taruma stream which flows into the Rio Negro river, as the water level at a major river port in Brazil’s Amazon rainforest hit its lowest point in at least 121 years on Monday, in Manaus, Brazil October 16, 2023. REUTERS/Bruno Kelly

“With the two phenomena acting simultaneously, we have a more intense drought that also affects a larger area of the Amazon biome,” Renato Cruz Senna, a meteorologist and researcher at the National Institute for Amazonian Research (INPA) in Brazil, told Mongabay.

A grim future

Over the years, several studies have indicated that with rising global temperatures, the Amazon will experience longer and more frequent droughts. A 2022 study, published in the journal Proceedings of the National Academy of Sciences (PNAS), said if humans continue burning fossil fuels at the current rate, the rainforest would experience major drought nine out of every 10 years by the year 2060.

A different 2022 study, published in the journal Nature, revealed that the Amazon has become slower at recovering from longer periods of drought over the past 20 years and is nearing its tipping point. Beyond the tipping point, it would transform from a lush green forest into a drier open savanna, releasing a large amount of stored carbon, which would, in turn, exacerbate global warming.

In the past five decades, between 17 and 20 per cent of the Amazon has been destroyed. Therefore, there is an urgent need to curb deforestation and greenhouse gas emissions to protect the Amazon, and, where possible, reforest the degraded swathes according to experts.

Elena Shevliakova, a physical scientist at Geophysical Fluid Dynamics Laboratory, part of the US National Oceanic and Atmospheric Administration, told Scientific American that the rainforest might appear like a distant world, but everyone on Earth is connected to its fate.

“Losing the Amazon is going to affect everybody,” she added.