The World-Warming Effects of Deforestation

May 11, 2008

Take a look at this map of the world’s largest carbon producers. Chances are, if you’ve switched on the TV news in the past five years, you’ve seen it—or something like it—a dozen times. And all the usual suspects are there; the U.S., caught in a neck-and-neck race with China, followed by the countries that collectively make up the European Union.

But look closely and you’ll see some unusual bright spots on that map. Brazil, for example, isn’t generally thought of as an industrialized carbon spewer, and yet, there it is. Indonesia, too, isn’t exactly known for the car-centered culture, sprawling, oversized homes, and meat-heavy diets that make America’s carbon footprint so large.

Calculations of national carbon emissions per capita are even more confusing. The top theee are, in order: Belize, Qatar, and Guyana. On this list, the USA doesn’t even crack the top ten, staggering in at 14th, just ahead of Trinidad and Tobago and a few places behind Canada. Yeah, and you were surprised when their currency started being worth more than ours. So what exactly is going on here?

The answer is deforestation. Though largely kept out of the public eye, cutting down forests has a tremendous amount of cascading effects that aggravate the effects of global warming. The first is fairly obvious—trees “breath” carbon dioxide, collecting it from the atmosphere and emitting oxygen in its place. Fewer trees mean less carbon is “inhaled” like this, and more of it ends up in the atmosphere.

Another reason deforestation is so destructive is that cleared trees are often burned, either for fuel or, in the case of swidden agriculture, to increase the viability of the soil. This burning releases large amounts of carbon dioxide into the atmosphere. Trees left to rot on their own actually hold onto a fair amount of their carbon; carbon-heavy fuels like oil and coal are formed largely through the decomposition of prehistoric plants.

Finally, many of the forested plots cleared by deforestation are then used for carbon-intensive tasks such as industrial agriculture. The fertilizers, feeds, and shipping costs inherent to large-scale food production severely limit the mitigation any plants grown on deforested plots have on carbon emission, and often, these crops leave the soil too depleted to allow full-growth forest to return to the area.

While celebrities (here’s an aging but fit Harrison Ford sacrificing a symbolic acre of his chest hair to the cause) and other activists have long opposed industrial-scale deforestation, it may prove a trickier habit to kick than America’s addiction to oil. Deforestation primarily takes place in developing nations, where it provides millions of people with a source of income, fuel, and food. While cap-and-trade plans may soon serious economic incentives to keep forests intact, it will take a concerted effort to make sure these benefits reach the people most closely affected.

Photo by Sarah and Jason