Comparison of the Short-term and Long-term Climate Change on the Catch Fluctuation of Pacific Cod, Gadus macrocephalus, in the Yellow Sea

The catch fluctuation of Pacific cod in the Yellow Sea is influenced by changes in hydrographic conditions due to the Siberian High (SH). The cold surface waters by SH in winter form the Yellow Sea Bottom Cold Water (YSBCW) that exists at the bottom of the Yellow Sea throughout the year. The cooling period of surface waters corresponds to the main spawning season of the Pacific cod in Korean waters. The water temperature changes impacted on the early survival of the Pacific cod in the Korean waters. The water temperature where the Pacific cod were caught ranged 6 to 10^oC. In early 1990’s when Pacific cod catches were lowest, YSBCW was restricted to the center of the Yellow Sea, but in 2007 when the catches were at highest level, YSBCW ranged over the entire Yellow Sea. However, the scenario by SH variation could not explain the influence by a global warming. The increase of the water temperature by global warming will affect the spawning area and spawning period of Pacific cod in the Yellow Sea. Therefore, the effect of SH will be coupled with the global warming through IPCC model for the catch fluctuation and its prediction of Pacific cod.