Friday, September 9, 2011
CO2 Aborption by Forests
It is often said that planting trees is good for the environment. Trees absorb CO2 as they grow, removing CO2 from the atmosphere and thus reducing the impact of the burning of fossil fuels on global warming. But how much CO2 do trees actually absorb, compared to the amount of CO2 released by human activities?
According to estimates published recently in Science, between 2000 and 2007 the forests of the world absorbed an amount of CO2 equivalent to only 30% of the CO2 released by just two human activities (the burning of fossil fuels and the production of cement). The other 70% generated by humans remained in the atmosphere (increasing the atmospheric CO2 concentration), or was absorbed by the world’s oceans. The 30% absorbed by trees represents a decrease from the 38% absorbed in the previous decade. That's because CO2 release into the atmosphere continues to increase and because forest absorption decreased, most likely because of continued destruction of tropical forests.
Plant a tree if you wish. But to solve the global warming problem we’ll need do a better job of preserving the world’s current forests, particularly in tropical regions. We'll also need to continue to try to reduce human-caused CO2 production.