amazon river
The Amazon River. Credit: NASA

The ways in which forests safeguard our planet are endless. And yet, we read and hear so much about some of them — like forests’ role as carbon sinks in combating climate change — that others can sometimes be overlooked. A study published Monday by the Proceedings of the National Academy of Sciences serves as a good reminder of how complex the forest and its roles in Earth’s climate really are.

The deforestation of rainforests is a problem normally framed in terms of the loss of carbon sinks or the loss of biodiversity. But what about the loss of rain? Brazil is home to 60 percent of the world’s biggest rainforest, the Amazon, and gets 80 percent of its energy from hydropower. The Proceedings of the National Academy of Science’s new study reveals that deforestation’s effects on hydropower may be more complex than they first appear.

Sunset on the Xingu River in Brazil's Amazon. Credit: Aviva Imhof/International Rivers
Sunset on the Xingu River in Brazil’s Amazon. Credit: Aviva Imhof/International Rivers

When trees are removed from alongside stream and river beds, the water flow initially increases, as the trees are no longer taking water through their roots, allowing it to flow directly into streams. But, without those trees, rainfall will eventually slow as well. Study co-author Daniel C. Nepstad of the Amazon Institute for Environmental Research tells The New York Times that rainforests “are in the equatorial sun, evaporating a huge amount of water that goes up through the stems and into the leaves and out into the atmosphere,” creating rainclouds. So, fewer trees mean less rain, which means less hydropower. That’s a problem for countries like Brazil.

The ways in which our lives depend on rainforests are too many to list. That’s why American Forests takes pride in our rainforest projects. This year, we’re returning to Indonesia to plant 35,460 trees across 140 acres of orangutan habitat in the Batang Toru forest in partnership with the Sumatran Rainforest Institute. We’re also embarking on our first project in Panama — home to the Western Hemisphere’s second largest rainforest — with longtime partner Sustainable Harvest International; we’re planting 20,000 trees across 79 acres in Coclé Province. Help us protect and restore forests like the rainforest. For the climate, for the water and for the people.