This week, international representatives at the United Nations will be discussing the rising rate of carbon emissions. The following segment from The New York Times sheds more light on the subject, a topic of heightened interest for all of us.
“Deforestation accounts for about 20 percent of global emissions of carbon dioxide. The assumption is that planting trees and avoiding further deforestation provides a convenient carbon capture and storage facility on the land.
That is the conventional wisdom. But the conventional wisdom is wrong.
In reality, the cycling of carbon, energy, and water between the land and the atmosphere is much more complex. Considering all the interactions, large-scale increases in forest cover can actually make global warming worse.
Of course, this is counterintuitive. We all learn in school how trees effortlessly perform the marvel of photosynthesis: They take up carbon dioxide from the air and make oxygen. This process provides us with life, food, water, shelter, fibre, and soil. The earth’s forests generously mop up about a quarter of the world’s fossil-fuel carbon emissions every year.
So it’s understandable that we’d expect trees to save us from rising temperatures, but climate science tells a different story. Besides the amount of greenhouse gases in the air, another important switch on the planetary thermostat is how much is reflected back to space. The dark colour of trees means that they absorb more of the sun’s energy and raise the planet’s surface temperature.”
– To Save the Planet Don’t Plant Trees – The New York Times, 19 Sep. 2014