Articles | Volume 22, issue 22
https://doi.org/10.5194/bg-22-7293-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-7293-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Assessing the efficacy of river-based ocean alkalinity enhancement for carbon sequestration under high emission pathways
Xiao-Yuan Zhu
State Key Laboratory of Marine Environmental Science & College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China
Shasha Li
State Key Laboratory of Marine Environmental Science & College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China
State Key Laboratory of Marine Environmental Science & College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China
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Lyu Yan and Wei-Lei Wang
EGUsphere, https://doi.org/10.5194/egusphere-2025-3185, https://doi.org/10.5194/egusphere-2025-3185, 2025
Preprint withdrawn
Short summary
Short summary
We studied how oceanic dimethyl sulfide (DMS) levels will change in a warming climate. Using an artificial neural network model, we projected DMS concentrations and sea-to-air flux from 1850 to 2100 under a high emission scenario. We found that DMS concentrations are expected to decline by the end of this century, with a faster rate of decrease after 2050. The sea-to-air flux of DMS shows a non-monotonic trend, increasing from 2015 to 2050 and then decreasing.
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Short summary
Ocean Alkalinity Enhancement (OAE) is a carbon dioxide removal (CDR) method that can simultaneously absorb CO2 and alleviate ocean acidification. Here, we evaluated the effectiveness of riverine OAE under high emission scenario in a fully coupled Earth System Model. The simulations show the riverine OAE effectively boosts ocean carbon uptake and partially combats ocean acidification, but continuous OAE is necessary to achieve the desired outcomes.
Ocean Alkalinity Enhancement (OAE) is a carbon dioxide removal (CDR) method that can...
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