“New Study Reveals Surprising Truth About Global Carbon Storage in Plants: Implications for Climate Change Action”
The carbon stored globally by plants is shorter-lived and more vulnerable to climate change than previously thought, according to a new study conducted by an international team led by Dr. Heather Graven at Imperial College London. The research, published in Science, reveals that existing climate models underestimate the amount of carbon dioxide (CO2) taken up by vegetation globally each year, while overestimating how long that carbon remains stored.
Dr. Graven, a Reader in Climate Physics at Imperial’s Department of Physics, stated that plants worldwide are more productive than previously believed. This means that while carbon is absorbed by plants at a faster rate than thought, it is also released back into the atmosphere sooner than predicted. This has significant implications for nature-based carbon removal projects, such as mass tree-planting initiatives, which rely on plants and forests to sequester CO2.
The study utilized radiocarbon (14C) dating, combined with model simulations, to understand how plants globally utilize CO2. By examining the accumulation of 14C in plants during a period with no significant nuclear detonations, researchers were able to assess the speed at which carbon moves from the atmosphere to vegetation and how long it remains stored.
The results showed that current models underestimate the Net Primary Productivity of plants globally and overestimate the storage time of carbon in plants. Co-author Dr. Charles Koven from Lawrence Berkeley National Laboratory emphasized the need to improve theories about plant growth and ecosystem interactions to better account for the rapid cycling of carbon between the atmosphere and biosphere.
Dr. Will Wieder from the National Center for Atmospheric Research highlighted the importance of accurate estimates of historical land carbon uptake for informing future climate change projections. The study underscores the value of radiocarbon measurements in unraveling the complexities of the biosphere and improving global climate models.
The research team also paid tribute to German physicist Ingeborg Levin, a pioneer in radiocarbon and atmospheric research, who passed away in February. The study’s findings emphasize the urgent need to ramp down fossil fuel emissions to minimize the impact of climate change, as nature-based carbon removal projects may have limited effectiveness in sequestering carbon over the long term.