Worldwide, forests absorb almost 9 billion tons of the greenhouse gas carbon dioxide every year, according to a new study published Thursday in the journal Science.
Want to save the planet? Plant a tree.
Or maybe a lot of them. Or maybe don't cut down so many.
These are the implications of a new study, which found that the world's forests play an unexpectedly large role in climate change, vacuuming up the greenhouse gas carbon dioxide (CO2) and storing the carbon in wood, according to research published online Thursday by the journal Science.
That, in turn, helps regulate CO2 concentrations in the atmosphere – and keeps the planet from overheating.
About one-quarter of the earth's land surface is covered by forest. But while scientists and schoolchildren have long known that trees absorb carbon dioxide, no one was sure how significant their role was, overall. Oceans, the atmosphere, and other terrestrial ecosystems also absorb carbon.
So how much is due to forests? Forests are incredibly diverse across different regions – tropical, boreal, temperate – and different conditions: growing fast, being cut back, dying off, or being replanted. Researchers have struggled to get a complete picture of how much impact forests alone had on climate. Until now.
Earth's forests, it turns out, play a dominant role in absorbing greenhouse gases in the atmosphere, acting like a giant sponge and soaking up on average about 8.8 billion tons of carbon dioxide each year, the new study led by the US Forest Service shows – or about one-third of fossil fuel emissions annually during the 1990-2007 study period. In the end, about 2.4 billion tons of solid carbon were locked away in wood fiber each year over that period – a surprise to scientists.