An anonymous reader writes: “Figuring out how much CO2 plants fix each year is a conundrum that scientists have been working on for a while,” said Lianhong Gu, co-author and staff scientist in ORNL’s Environmental Sciences Division.
“The original estimate of 120 petagrams per year was established in the 1980s, and it stuck as we tried to figure out a new approach. It’s important that we get a good handle on global GPP since that initial land carbon uptake affects the rest of our representations of Earth’s carbon cycle.”
“We have to make sure the fundamental processes in the carbon cycle are properly represented in our larger-scale models,” Gu added. “For those Earth-scale simulations to work well, they need to represent the best understanding of the processes at work. This work represents a major step forward in terms of providing a definitive number.”
The new OSC approach yielded a total of 157 petatons per year, equivalent to the emissions of 37.36 billion international combustion vehicles.