New research just published in the journal Nature say that plants, trees, and soil are absorbing carbon about 25 percent faster than scientists previously thought.
A team of scientists headed-up by Lisa Welp-Smith of the Scripps Institution of Oceanography have developed a new, more accurate, method of determining how much plants absorb and release carbon. The study estimates that global plant life take up between 150 billion and 175 billion metric tons of CO2 from the atmosphere each year, 25 to 45 percent more than the previous estimate of 120 billion metric tons annually.
The research is an important step for future climate models, emphasizing the vital role plant life plays in regulating the carbon cycle. But Welp-Smith cautions that the study is only a beginning and making conclusions about the exact nature of a carbon sink plants represent is “several steps beyond the paper.”
“Just because there is more photosynthesis doesn’t mean there is necessarily a greater carbon sink from the land biosphere,” Welp-Smith said. “It means more CO2 is passing through plants, not that it actually stays there very long.”
Welp-Smith explained that plants burn some of the sugar produced in photosynthesis, producing energy the plants need to live and grow, but in the process release some of the absorbed CO2 back into the atmosphere. A process that may also be more rapid than previously thought, offsetting the increased rate of initial CO2 absorption.
But whatever determinations come from future studies, the research is important in helping scientists further understand and quantify the role of plants in the global carbon cycle.
“If we are right, and GPP needs to be revised upward by about 25 percent, it means that our fundamental understanding of how land plants function on the global scale is still a bit fluid,” Welp-Smith said.
Colin Anderson, an atmospheric chemist and co-author of the study, said the research increases our knowledge of “what’s really going on in the atmosphere.”
“It’s still too early to tell what the final impact of this will be on estimates of future climate change,” Allison said. “But by tying this down, it means that from now we will have a better constraint that might modify our understanding of what those future impacts could be.”