Surface distribution of alkalinity and specific alkalinity and their application to water mass tracing in Kuroshio area of the East China Sea

Surface distribution and seasonal variation of alkalinity and specific alkalinity in Kuroshio area of the East ChinaSea and their application to the water mass tracing are discussed in this paper.Results show a distinct seasonal variation of the alkalinity,which is concerned with the process of vertical mixing.Different specific alkalinity in various water masses has been found.On the basis of the difference of the specific alkalinity and the distribution of alkalinity,two water fronts in summer season,located at 27°-30°N and 124°-1 27°E, (Ⅰ),and at the northern waters about one latitude from the Taiwan Island, (Ⅱ); one in winter season at about one longitude from coast of mainland of China and 26°-30°N were found.In summer season,about 1-2 longitudes eastward shift of front (Ⅰ) is found by comparison of data in May and August.And the high alkalinity of the northern East China Sea in summer season may be caused by the Huanghe River runoff flowing southward along with the Huanghai Sea Coastal Current.