＊NIFS Serial Ocenographic Observation (NSO): NIFS has observed regularly the climate environment and ecosystem in coastal waters of Korea using its research vessels (R/Vs) since 1961. 

It is very rare case and hard to be found even around the world to systematically observe the ocean acidification across a wide range of sea areas for a long time. 

The analysis of the obtained data showed that the pH of the East Sea had fallen by 0.040 units and the West and South Sea showed 0.055 and 0.029 decreases in pH levels.

When compared to the pH decrease (- 0.027) observed at the station near the Hawaiian Islands in the North Pacific, the decreases in the East and South Sea are 1.5 and 2 times higher while that of the West Sea stayed at a similar level. 

The analysis showed that such rapid acidification in Korean waters was mainly attributed to △ rising seawater temperature due to drastic ocean warming and △the ocean’s absorption of CO2 from the atmosphere.