3 ways climate change affects tropical rainforests

© Pete Oxford/iLCP

Not everyone lives in a tropical rainforest — but everyone benefits from them.

Home to nearly half of the plants and wildlife on Earth, tropical rainforests perform an essential function for the climate by absorbing carbon dioxide. Unfortunately, cutting down these forests is releasing carbon into the atmosphere and driving climate change — in fact, deforestation causes 15 percent of all human-induced carbon emissions.

Multiple studies show that climate change is harming tropical forests. But there’s hope. On International Day for the Conservation of Tropical Forests, Human Nature explores three issues and potential solutions.

1. Changing climate leads to forest degradation.

Models predict that by 2050, temperatures in the Amazon will increase by 2-3 degrees Celsius — leading to intensified droughts.

“Obviously, more intense drought seasons are a real problem because they cause more fires and they cause more fire spread,” said Karyn Tabor, director of early warning systems at Conservation International.

Studies in the Amazon River basin predict that a rise in temperature corresponds with a 10-20 percent reduction in rainfall. As temperatures increase, so do forest fires. Tropical rainforests typically get over 100 inches of rain a year, but each year this number decreases — creating a chain effect of consequences.

“In the tropics, especially the tropical Amazon — the forests are not meant to burn. So, once these forests burn, then the forests are really degraded and they’re more likely to burn again,” said Tabor. “The key is preventing the fires and also improving resilience of these forests — keeping them intact, trying to prevent degradation.”

The good news: Tabor developed Firecast, a NASA-funded forest fire monitoring and alert system for the tropics, which uses satellite inputs to alert to dangerous fire weather conditions and detect fires before they spread. “The satellites will detect a fire and within a couple hours we can send an alert to decision-makers in the field about where fires are happening,” she said. Technological innovations are a way in which science and data can be used to combat climate change.

2. As the forest degrades, food shortages increase.

Studies show that since 1980 a decrease in annual rainfall has created a steady decline of corn, wheat, soybeans and rice. A rise in global temperatures is causing trees and plants to produce fruit earlier or later than before — throwing off the species that feed on them, including humans: About 1.2 billion people in the world rely on tropical rainforests for survival.

Local farmers depend on the crops commonly grown in the rainforest including coffee, bananas, lemons and peanuts to make money and to feed their families.

The good news: Extreme weather events are becoming the norm, but conservation groups are working with farmers to address this issue. In a small community of Liberia, Conservation International helped created a tree-crop nursery on an abandoned farm. “[Tree crop nurseries] provide additional opportunities to grow and sell food, and they serve as a cover crop to maintain and rejuvenate the soil,” said Peter Mulbah, deputy country director of Conservation International’s Liberia office and a climate change adviser to the Liberian government in an interview with Human Nature last year. Farmers surrounding tropical rainforests have no choice but to change their methods to the most climate-smart agriculture.

3. Decreased forests and food shortage results in an increased number of threatened species.

Tropical Rainforests are home to nearly 30 million species of plants and animals, which heavily rely on another for survival. As plant growth dwindles, these animals become vulnerable.

The most at-risk species are those that rely on flower nectar for survival, namely bees and hummingbirds, as well as those that rely on fruit from the trees, such as monkeys, apes and parrots.

Species rely on cues from the environment for survival. As the climate continues to change the species will be forced to adapt, a phenomenon known as phenology. When one factor is thrown off, such as temperature or rainfall, it can disrupt the cycle of how the species function. Research shows that most land animals will not be able to adapt quickly enough to the changing climate.

The good news: Establishing protected habitats is key to the survival of endangered species. Conservation International created a coalition, Tropical Ecology Assessment and Monitoring, to use data and analysis to study species in protected areas. The research found that 17 percent of the animal populations increased, 22 percent remained constant, and 22 percent decreased. The majority of endangered species remaining constant or growing shows the importance of protected areas for threatened species.

Jessica Pink was an editorial intern for Conservation International.


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