A recent study led by Dr. Heather Graven from Imperial College London has found that the carbon stored globally by plants is shorter-lived and more vulnerable to climate change than previously thought.
Published in the journal Science, the research suggests that existing climate models underestimate the amount of carbon dioxide (CO2) taken up by vegetation annually and overestimate how long this carbon remains sequestered.
Dr. Graven, Reader in Climate Physics, stated that plants worldwide are more productive than initially believed. However, this faster uptake of carbon means it is also released back into the atmosphere sooner. This revelation impacts the effectiveness of nature-based carbon removal strategies, highlighting the limited longevity of carbon stored in living plants and underscoring the importance of reducing fossil fuel emissions.
The study utilized radiocarbon (14C), especially the increased levels from nuclear bomb testing in the 1950s and 1960s, to observe how quickly plants absorbed CO2. The findings indicate that widely-used models both underestimate plants’ productivity and overestimate the duration of carbon storage in vegetation.
Co-authors, including Dr. Charles Koven from Lawrence Berkeley National Laboratory and Dr. Will Wieder from the National Center for Atmospheric Research, emphasize the need to revise climate models to better reflect the rapid carbon cycling between the atmosphere and biosphere. The study underscores the importance of improving our understanding of the terrestrial carbon cycle to enhance climate change projections.
The research, which provides critical insights into carbon dynamics, also serves as a tribute to German physicist Ingeborg Levin, a pioneer in radiocarbon and atmospheric research, who passed away in February.
