What Exactly Is Deforestation Doing to Our Planet?

This week, world leaders gathered in Bonn, Germany for a climate summit. They’re there to discuss implementation of the Paris Agreement, a landmark accord in concert with the United Nations Framework Convention on Climate Change. The Agreement seeks to prevent global temperature change from reaching the 2-degree-Celsius rise which mainstream science has deemed the point at which the impact in irreversible.

As a part of the Bonn summit, Syria agreed to join the Paris Agreement, leaving the United States of America as the only nation on Earth which is not a part of the global effort.

Much has been said of that 2 degree (3.6°F) threshold. It is somewhat controversial; some argue that, as we’re already two-thirds of the way to that point, it’s unrealistic to think we won’t pass a 2 degree rise this century. In fact, a World Bank report suggests “present emission trends put the world plausibly on a path toward 4°C [7.2 degrees Fahrenheit] warming within the century.” But the 2 degree threshold was chosen as it’s believed that’s the point at which ice sheets in Greenland and West Antarctica become unstable and begin to melt at an unstoppable rate.

Should the West Antarctic ice sheet melt, it would cause sea levels to rise more than 10 feet; there are about 12.3 million people in the U.S. alone living on land less than 10 feet above sea level. The melting of Greenland’s ice sheet would cause sea levels to rise an additional 23 feet.

The main goal of the Paris Agreement is to reduce climate change by focusing on greenhouse gas emissions. Deforestation is responsible for as much as 10 percent of all global warming emissions. How is this? Most trees–and certainly those in forests–absorb carbon dioxide and then release oxygen, storing the excess carbon. When trees are cut down and burned or simply allowed to rot, that carbon is released into the air as carbon dioxide.

It has been difficult to get people to care about climate change and that is likely, in part, because that 2-degrees-by-the-end-of-the-century disaster scenario we hear about so frequently is outside the natural lives of the majority of people alive today. As a Yale poll found, nearly 60 percent of Americans believe that climate change will “harm people in the United States,” but only 40 percent believe it will “harm me personally.”

Deforestation in Malaysia

All of this land was once rainforest, it's been torn down for palm oil plantations. (Photo: EcoHealth Alliance)

But research shows, time and time again, deforestation is already impacting us negatively in myriad ways.

A recent paper published in the European Geosciences Union journal Biogeosciences found that land cleared for human use was 10°C warmer than forested areas. The average mid-morning temperature in Jambi, a province on the Indonesian island of Sumatra where deforestation rates are high, rose 1.05°C between 2000 and 2015. That 15 year increase represents more than half of the 2°C rise scientists have deemed catastrophic should it happen in the next 85 years.

NOAA research released this week shows that deforestation has doubled, or even quadrupled, the frequency of hot, dry summers in some parts of the world. The areas affected most are North America and Europe.

But deforestation impacts human health in an even more direct way as well. One Health practitioners have, for years, understood that deforestation creates more incidences of human-wildlife interaction and, therefore, a greater frequency of zoonotic disease spillover into human populations.

New research recently published in Nature’s online journal Scientific Reports found an almost universal two year link between deforestation and Ebola outbreaks. That is to say, areas which experienced significant forest loss were highly likely to see an Ebola outbreak in humans two years later. It’s a striking representation of the One Health concept; destruction of natural forest presents an immediate risk to the people living in that area. Some of those Ebola outbreaks are contained, some, like the West African outbreak which lasted from 2013 to 2016 and killed more than 11,000 people, spread quickly across the region, to the U.S. and Europe.

Indonesia has the highest rate of deforestation in the world. Research indicates the country felled 15 million acres of forest between 2000 and 2012. (Photo: EcoHealth Alliance)

The link between deforestation and the spread of disease is both clear and scientifically proven. Deforestation is most often for agricultural purposes, as a ballooning global population requires more and more food. While thoughtless clearing of the land is much simpler, it often exposes livestock to zoonotic disease which ends up costing local farmers their livelihoods, if not their lives. In the first known outbreak of Nipah virus in Malaysia, the government had to cull more than a million domesticated pigs who were transferring the virus to people, having caught it themselves because they were eating fallen fruit from groves which bats had also fed on.

One Health is about bridging the gaps between the work of individual disciplines. Protecting plants and animals is about protecting human health. And protecting human health requires the protection of those species with which we share our planet.