NASA: The average annual ebb and flow of Carbon Dioxide
Earth’s oceans and land cover are doing us a favor. As people burn fossil fuels and clear forests, only half of the carbon dioxide released stays in the atmosphere, warming and altering Earth’s climate. The other half is removed from the air by the planet’s vegetation ecosystems and oceans.
Terrestrial plants — from towering Douglas firs to moss growing on rocks — take up carbon dioxide from the atmosphere during photosynthesis, processing it into carbon-containing leaves, stems, branches and more.
“The land helps to mitigate something like a quarter of the carbon dioxide emissions,” said Jeffrey Masek, chief of the biospheric sciences laboratory at NASA Goddard. “The question is: What will happen in the future? Can we count on this to continue? Or are land processes going to saturate, in which case we’d see our atmospheric carbon dioxide concentration start to increase much more rapidly.”
Ocean scientists are facing similar questions about carbon. The ocean water itself absorbs carbon dioxide from fossil fuel emissions. Doing so, however, changes the chemistry of seawater. As surface water in the ocean continues to warm, uptake of carbon dioxide will slow down.