Online seminar by Dr. Kyungmin Noh from Geophysical Fluid Dynamics Laboratory
01 October 2025
KST 10:00
Join us online: https://pusan.zoom.us/j/81974221228?pwd=PLYM
Climate stabilization scenarios limiting global warming to 1.5-2℃ targets generally require augmentation of natural atmospheric CO2 removal with additional carbon dioxide removal (CDR) around 2-3 PgC year-1 solutions sustained over the next century. Among marine-based CDR strategies, iron fertilization is still regarded as a potential solution. Here, we assess the long-term additionality and durability of carbon uptake in large-scale ocean iron fertilization using an Earth System Model under emissions-driven scenarios. Our simulations suggest that sustained century-scale fertilization of the southern sector of the Southern Ocean could provide a moderate contribution to ambitious CDR goals (~30PgC, or 0.3PgC/yr) with relatively high durability (~50%). In the other iron-limited regions, that the additional carbon uptake induced by fertilization is largely offset by net outgassing in the non-fertilized regions-compensated by 70-100%—and becomes nearly negligible within a few decades after fertilization ceases. These CDR limitations arise from multiple biogeochemical processes by fertilization: local and remote nutrient depletion, re-entrainment of previously sequestered carbon into surface waters, incomplete nitrate drawdown, and reduced phytoplankton C:P ratios in the fertilized areas. Overall, our results highlight the limited efficacy of large-scale iron fertilization as a mitigation strategy. Furthermore, application of the standardized design in coordinated intercomparison is needed to better assess the robustness of these limitations across international climate modeling centers.
Zoom Link: https://pusan.zoom.us/j/81974221228?pwd=PLYMZaz5ffdPbZYT1DSHAilWQAoPbN.1
Meeting ID: 819 7422 1228
PW: 767052