Questões de Concurso

First study of all Amazon greenhouse gases suggests the

damaged forest is now worsening climate change

The Amazon rainforest is most likely now a net contributor to warming of the planet, according to a first-of-its-kind analysis from more than 30 scientists.

For years, researchers have expressed concern that rising temperatures, drought, and deforestation are reducing the capacity of the world’s largest rainforest to absorb carbon dioxide from the atmosphere, and help offset emissions from fossil-fuel burning. Recent studies have even suggested that some portions of the tropical landscape already may release more carbon than they store.

But the inhaling and exhaling of CO2 is just one way this damp jungle, the most species-rich on Earth, influences the global climate. Activities in the Amazon, both natural and human-caused, can shift the rainforest’s contribution in significant ways, warming the air directly or releasing other greenhouse gases that do.

Yet no team had ever tried to assess the cumulative impact of these processes, even as the region is being rapidly transformed. The research estimates that atmospheric warming from all of these sources combined now appears to swamp the forest’s natural cooling effect.

The damage, however, can still be reversed. Halting global emissions from coal, oil, and natural gas would help restore balance, but curbing Amazon deforestation is a must, along with reducing dam building and increasing efforts to replant trees. Continuing to clear land at current rates appears certain to make warming worse for the entire world.

Internet:<www.nationalgeographic.com> (adapted).