Each term of heat badget equation in the eastern Yellow Sea was calculated and the variation in relation to meteorological condition was shown for the period from September 1973 to February 1974, At Mal-do near Gunsan the maximum heat exchange occurred at the last ten days of December (--522 1y/day), while at Sunmi-do near Incheon it occurred at the middle ten days of November (--665 1y /day), The contribution of the sensible heat to total heat exchange increased rapidly, while the effect of cloudiness decreased to be negligible in winter. The values of the heat exchange fluctuated considerably with the periodic occurrence of the cold Siberiaa air mass. The mean evaporation heat estimated indirectly from the aerological data was 32 ly/day at the northern part and 269 ly/dlY at the southern part of the Yellow Sea in December 1973.
The large two-boat trawl is of importance in Korean fishery. It occupied 12.8% of total catches in 1974. The author analysed the reports of six large two-boat trawlers operated at the Yellow Sea and the East China Sea, in the term from September 1975 to March 1976. The results obtained are as follows; (1) 1,710 of total hauls are operated in the term, and the total catches amounted 559, 181kg. Then, 325kg of catch per unit effort (C. P. U. E) are obtained. The catches are specified into 28% of soles, 12% of shrimp, 8% of yellow corvenia, hair tail, kang-dari, and the rest of miscellanous fishes. (2) C. P. U. E. of the southern sectors of the Soheaksan Is. represented superior catches to compared with others sectors. (3) The monthly variation of C. P. U. E. between sea eel and yellow corvenia revealed positive correlation, whereas between sole and shlimp, between hair tail and rays revealed negative correlation respectively.