## 1 Introduction  
Carbon capture and storage (CCS) is one of the technologies used to mitigate global warming and ocean acidification. Various CCS methods are available and can be categorized into inland or ocean geological storage, direct injection and so on. Among these, only inland and ocean geological storage are considered viable following the prohibition of the direct injection method due to its uncertain environmental impacts. CO2 geological storage is a method for capturing CO2 from power plants or industrial processes without releasing it into the atmosphere, transporting it to sites suitable for geological storage, and storing it stably underground for the long term. Furthermore, it has the advantage of large-scale CO2 reduction. Geological storage has been mainly carried out in countries with sufficient inland storage space. However, for countries with limited inland space such as Korea, Japan, Norway, and the United Kingdom, ocean geological storage is considered the most feasible option. The Sleipner CO\({}_{2}\) injection project in Norway was the world's first industrial offshore CO\({}_{2}\) ocean geological storage project, through which more than 16 Mt of CO\({}_{2}\) was injected from 1996 to 2014. The injection rate was approximately 0.9 Mt/y during the early years and reduced slightly during later years due to reduced gas flow from the Sleipner Vest [1,2]. From 2008 to 2012, 1.6 Mt of CO\({}_{2}\) was injected into the Snahvit gas field. Although the injection was occasionally halted due to operational challenges at the LNG plant during that period, approximately 0.5 Mt of CO\({}_{2}\) was stored in the well, and injection has continued since 2011 [3]. A large-scale CCS demonstration project in Japan's Tomakomai area, which can store 0.1 Mt/y of CO\({}_{2}\) in two reservoirs that lie 1100 m and 2400 m below the seabed, is being undertaken by the Japanese government [4]. In the case of Korea, a CO\({}_{2}\) storage project that can store 1 Mt/y was being constructed near the southeastern coast of Korea, but was temporarily stopped in 2018. To utilize any kind of CCS technology, public acceptance must be ensured through the risk assessment of CO\({}_{2}\) leakage, monitoring the behavior of leaked and dissolved CO\({}_{2}\) (DCO\({}_{2}\)), and environmental assessment of the leaked CO\({}_{2}\). The Quantifying and Monitoring Potential Ecosystem Impacts of Geological Carbon Storage (QICS) project in the UK was created to assess the environmental impact of CO\({}_{2}\) release experiments in Ardmucknish Bay [5]. [PERSON] et al. [6] investigated the dynamics of leaked CO\({}_{2}\) bubbles in a plume in the bay through observational data obtained from the QICS project. Because of the limitations of field experiments, studies utilizing computational fluid dynamics (CFD) have been carried out to estimate the behaviors of leaked CO\({}_{2}\) and DCO\({}_{2}\). The highly complex phenomena that occur when liquid CO\({}_{2}\) is injected into the deep ocean was numerically studied by Eulerian-Eulerian two-phase CFD simulations by [PERSON] and [PERSON] [7] and Eulerian-Lagrangian simulations by [PERSON] and [PERSON] [8]. [PERSON] et al. [9] developed a multi-scale ocean model, which builds a bridge between smaller near-field scale and larger regional-scale models to predict the fate of DCO\({}_{2}\) in the deep ocean. [PERSON] et al. [10] conducted numerical simulations on the behavior of CO\({}_{2}\) bubbles and droplets leaked from the seafloor into water columns in uniform flows perpendicular to the leakage band. They showed that CO\({}_{2}\) dissolved in seawater before returning to the air under their simulation conditions, which indicates that the ocean can play the role of a buffer that does not allow CO\({}_{2}\) to return to the atmosphere. [PERSON] et al. [11] developed a multi-scale numerical method to predict the behavior of dissolvable CO\({}_{2}\) bubbles leaked from the seafloor and dissolved mass in the ocean.