제목: Futility of Iron Fertilization for Carbon Sequestration in 95% of World Ocean Area​​​​​​

​​​​​​​​​​​​​​​​​​연사: 노경민 박사 (Princeton University)​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

장소: 과학관 553호​​

Abstract:

Rapidly increasing carbon dioxide (CO₂) emissions over recent decades, coupled with the potential for further increases in the coming decades, have driven global efforts to remove and sequester carbon to mitigate the impacts of climate change. Among the proposed marine-based carbon dioxide removal (mCDR) strategies, ocean iron fertilization has been revisited because of its uncertainties in global-scale efficacy. To evaluate the efficacy of carbon sequestration via iron fertilization, we utilized the global fully coupled carbon-chemistry-climate Earth system model, GFDL-ESM4.1. Our simulations suggest that seasonally sea-ice-covered zones in the Southern Ocean are the only significant regions for carbon sequestration in response to iron fertilization. In other regions, additional carbon uptake from fertilization is nearly offset by 70% to 110% due to reductions in non-fertilized areas. This compensation arises from enhanced surface nutrient depletion, which emerges in tropical oceans through biogeochemical teleconnections. Lastly, in assessing the impact of mCDR on atmospheric CO₂, our findings underscore the importance of emission-driven experiments and the variability of carbon cycle components. To fully assess the potential effectiveness of mCDR, robust measurement, monitoring, reporting, and verification (MMRV) systems are essential, taking into account the global implications of carbon dioxide removal methods.​