02 Aug 2012:
Planet’s Carbon Storing Capacity
Keeping Pace with Human Emissions
A new study finds that earth’s oceans and lands continue to absorb more than half of the human-caused greenhouse gas emissions
, suggesting that the planet has not yet reached its carbon-storage capacity even
as emissions continue to escalate. Writing in the journal Nature
, a team of U.S. scientists calculate that the world’s natural systems — including seas, forests, and soils — have absorbed about 55 percent of the roughly 350 billion tons of greenhouse gases emitted during the last 50 years. With human-based emissions rising steadily over five decades, those systems have had to absorb an ever-increasing amount of carbon, storing an estimated 5 billion tons in 2010 compared with 2.4 billion tons in 1960, the study found. These calculations are consistent with findings by the Global Carbon Project, according to Reuters
. The planet’s capacity to store carbon has been a critical factor in preventing an even greater increase in global temperatures, but authors of the new study say that storage capacity will not remain indefinitely. “It’s not a question of whether or not natural sinks will slow their uptake of carbon, but when,” said Ashley Ballantyne, a researcher at the University of Colorado and lead author of the study.