What would happen if the Amazon Rainforest disappeared? - Anna Rothschild

78,748 views ・ 2025-01-28

TED-Ed


Please double-click on the English subtitles below to play the video.

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You’re traveling down the Amazon when suddenly you spot a flash of pink.
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It's a male Amazon river dolphin.
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It's thought that the pinker he is,
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the more attractive he’ll be to a potential mate.
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This unique dolphin species is native to the Amazon,
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and its future is in peril.
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As of 2022, humans have deforested 17% of the Amazon.
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And scientists warn that we may be approaching a tipping point—
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when enough of the forest is lost that large swaths of the ecosystem die.
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It’s like removing bricks from a house.
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Take one or two and the house will keep standing.
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But remove too many and the whole thing will start to cave in.
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What happens in the Amazon affects the rest of the planet.
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To explore this relationship,
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let’s examine what would happen if the entire Amazon disappeared.
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The Amazon is sometimes called Earth's air conditioner.
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Each day, the Sun beats down on its 390 billion trees.
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The plants photosynthesize, opening their pores, and losing water to evaporation.
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This process, known as transpiration,
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cools both the plant and the surrounding air,
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and helps form clouds that move over the forest.
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Through this, the Amazon cycles around 20 trillion liters of water daily.
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If the rainforest disappeared,
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there would be little transpiration to feed the rain clouds.
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The heat from the Sun would radiate back into the atmosphere,
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forming chimneys of hot, dry air.
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The local temperature would increase by several degrees
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and rainfall in the region would drop.
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Crops and animals would die as the area—
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home to 10% of the world’s known species and 30 million people— transforms.
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Villages would be stranded as rivers dry up.
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Dead fish would contaminate the drinking water.
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Air quality would plummet as wildfires spread.
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In fact, we’ve already started to see this during recent droughts.
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And effects would stretch far beyond the Amazon.
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Air circulates around the planet,
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so any change in temperature or pressure in one region
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can influence currents and winds thousands of kilometers away.
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These effects are hard to predict.
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Some models estimate that losing just 40% of the Amazon
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would reduce rainfall in the agricultural center of Argentina
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over 3,000 kilometers away.
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The complete disappearance of the rainforest and its water cycle
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could cause 50% of the snowpack to melt in the Sierra Nevadas,
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and a 20% reduction in rainfall in the coastal northwest United States.
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California’s Central Valley, which grows a quarter of the US’s food,
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could face dwindling water supplies.
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We’d lose one of the world’s largest natural carbon sinks.
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Some scientists estimate that temperatures worldwide would rise an additional 0.25°C
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above current climate predictions.
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And while that might sound small,
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even a slight rise in global temperature can increase severe weather events
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and habitat loss.
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It’s a tragic irony that part of what makes the Amazon so valuable
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is also the source of its destruction.
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By some estimates, exploiting the Brazilian Amazon
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for farming, cattle ranching, and more
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generates the equivalent of up to 98 billion USD annually.
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Yet by stopping deforestation and practicing fire management
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and sustainable agriculture,
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some researchers predict the region could generate even more wealth
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than it currently does.
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So how close are we to reaching a tipping point?
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We probably won't know until it's too late.
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So far, the Amazon has remained resilient.
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But its very existence relies on transpiration from trees
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to keep water cycling through it.
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Removing living trees in one location leaves the surrounding area dehydrated—
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and more vulnerable to drought and wildfires.
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But there are steps we can take today.
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First, we can choose to buy products from companies
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that refuse to procure from deforesters.
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Studies have shown that planting new trees can help restore the forest’s water cycle—
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though it takes a long time for them to capture as much carbon
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as an old growth tree.
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And native stewardship can have a huge impact.
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There are over 1.5 million Indigenous people living in the Amazon.
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From 2001 to 2021, portions of the rainforest that weren’t managed
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by native people emitted 270 million metric tons of carbon to the atmosphere
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thanks to deforestation and burning.
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Yet during that same period,
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portions managed by Indigenous people removed well over 300 million metric tons.
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The rewards of protecting the Amazon benefit all of us—
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but the impact of destroying it is already being felt
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by those living there today.
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