Park, Y.-G.; Kim, Y.H.; Seo, S.; Hwang J.H., and Ha, H.K., 2020. Environmental impact assessment of carbon storage using a CO₂ bubble model. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 138–142. Coconut Creek (Florida), ISSN 0749-0208.

Carbon storage in underwater geological structures is considered as a way of mitigating global climate change. One of the environmental issues related to carbon storage is the leakage of carbon dioxide from the storage. A model for tracking CO₂ bubbles in the water column has been developed to assess the environmental impact of CO₂ leakage from a shallow site that is under consideration in Korea. The dependences of the rising velocity and the solubility to bubble size are taken into account while assuming spherical bubbles of from 0.1 mm to 18 mm in diameter. Since the study area is a shallow water environment (∼170 m), leaked CO₂ bubbles reach the surface within 20 minutes during which the local horizontal currents transport the bubbles less than 500 m. While rising to the surface, less than about 2x10^-7% of leaked CO₂ is dissolved into seawater. The remaining amount is released into the air. If it is assumed that 1x10⁵ ton of CO₂ is leaked as bubbles, the pH of seawater that is influenced by the CO₂ bubbles at the absence of ocean currents would be lowered by less than 0.01 on the average. If the lateral dispersion of the bubbles by ocean currents is considered, the effect would be smaller.