Model study on even diffusion of CO2 released from 30 ships in mesoscale deep ocean

Abstract

Abstract Among possible carbon capture and storage methods to mitigate the global warming, the direct injection of CO 2 into the deep ocean by the moving ship method, is considered to be a feasible way and expected to minimize its environmental impacts on ma rine organisms in the vicinity of the injection points. In this study, a simple but effective numerical model for the given practical scenario of very large system was developed with adopting moving and nesting grid technique and low-wavenumber forcing technique. The calculated results show that the maximum change of additional p CO 2 is lower than a non-observed effect concentration, +5,000 μatm, in the both small and mesoscale domains. This indicates that the scenario of 30 ships with different length of injection pipes injecting total CO 2 of 50 million t/yr and moving in the 111 km × 333 km operation area is efficient and effective. The developed techniques demonstrated its efficiencies and applicability to give an outline for the optimization of the CO 2 ocean sequestration system, by which biological impacts should be minimized and insignificant.