Bomb radiocarbon evidence for strong global carbon uptake and turnover in terrestrial vegetation

Journal article

Vegetation and soils are taking up approximately 30% of anthropogenic CO2 emissions because of small imbalances in large gross carbon exchanges from productivity and turnover that are poorly constrained. We combine a new budget of radiocarbon (14C) produced by nuclear bomb testing in the 1960s with model simulations to evaluate carbon cycling in terrestrial vegetation. We find that most state-of-the-art vegetation models used in the Coupled Model Intercomparison Project underestimate the 14C accumulation in vegetation biomass. Our findings, combined with constraints on vegetation carbon stocks and productivity trends, imply that net primary productivity is likely at least 80 PgC/yr presently, compared to 43-76 PgC/yr predicted by current models. Storage of anthropogenic carbon in terrestrial vegetation is likely more short-lived and vulnerable than previously predicted.

Authors: Graven, HD; Warren, H; Gibbs, HK; Khatiwala, S; Koven, C

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Association for the Advancement of Science
• Journal: Science
• Volume: 384
• Issue: 6702
• Pages: 1335-1339
• Publication date: 2024-06-20
• Acceptance date: 2024-05-09
• DOI: 10.1126/science.adl4443
• EISSN: 1095-9203
• ISSN: 0036-8075
• Language: English