Current computer models may have overestimated expected future levels of CO2 in the atmosphere, according to research released today.
And the models may need to be corrected to accurately predict the ramifications of climate change.
The scientists say current forecasts don’t account for the slow diffusion of atmospheric CO2 inside plant leaves and underestimate the contribution of increasing CO2 to plant growth by as much as 16%.
The study by Robert E. Dickinson of the The University of Texas at Austin and colleagues is published in the journal PNAS.
Australian experts are cautious about the findings, saying there are many factors at work.
The study is an attempt to explain why CO2 in the atmosphere isn’t rising even faster.
Pep Canadell, at the CSIRO’s Global Carbon Project, says having more carbon taken up by plants would slow climate change.
“But there are many other processes which lay in between this work and the ultimate capacity of terrestrial ecosystems to remove carbon dioxide and store it for long enough to make a difference to atmospheric CO2 trends,” he says.
“Additional research will show the net effect on atmospheric CO2, which undoubtedly, will still fall within the already well-established large uncertainty of future projections of the land carbon sink due to other processes, such as responses to nutrient limitation, fires, and the thawing of permafrost.”