A recent Nature article discusses the status of forest-based carbon sinks in general, with special emphasis on an African sink that is estimated to be absorbing 1.2 billion tonnes of carbon dioxide per year: nearly twice the level of Canada’s 2006 emissions.
Today’s launch of the Orbital Carbon Observatory should help scientists to gain a better sense of how carbon dioxide is moving through and between the atmosphere, hydrosphere, and biosphere.
All told, the article estimates that 18% of human carbon dioxide emissions are being absorbed by tropical forests. The article highlights the uncertainties involved in the future trajectory of absorption by this sink. It may be that additional atmospheric CO2 causes it to maintain or even increase its absorption in the medium term. Conversely, it may be that the trees will reach a maximum size and cease to absorb further carbon, or that temperature and precipitation changes caused by global warming will restrict growth.
In any event, humanity will be in a better position to plan for the future once we have a deeper understanding of the nature of existing carbon sinks, and better projections for how they will respond to future conditions. In the mean time, working to avert further tropical deforestation is an important precautionary step.