Strategy of environmental assessment for CO2 ocean sequestration

CO
₂
ocean sequestration research should focus on determining effectiveness as well as environmental consequences. To investigate the validity of CO
₂
ocean sequestration, it is important that dissolution and dispersion behaviors of sequestrated CO
₂
into the ocean are understood. In addition, ocean environmental impact including marine ecosystem should be predicted. Sequestration research requires development of new cost-effective observation technique to monitor dilution and diffusion of sequestrated CO
₂
. In order to assess the environmental impact of the CO
₂
ocean sequestration by seagoing observation, several technologies (in-situ pH/pCO
₂
sensor, tracking neutral buoy system, towing multi-layer monitoring system, automatic elevator) were developed and the performance of these technologies were confirmed by the sea trials.