@@ CO2, as a greenhouse gas, is absorbed by and released from seawater, depending on the difference of its partial pressure between the air and the seawater. Increased atmospheric CO2 concentration due to industrial activities is known to have enhanced the process of CO2 dissolution into seawater from air. However, such a capacity of seawater to sink CO2 has been greatly reduced, while CO2 make the seawater less alkaline (ocean acidification).