On the Huanghai (Yellow) Sea circulation: A review by current measurements

Abstract

The Huanghai (Yellow) Sea circulations suggested in the past were constructed mostly based on hydrographic data or simple numerical models, and were not rigorously compared with direct current measurements. Our present understanding of the Huanghai Sea circulation is still very poor and superficial. To evaluate our present knowledge about the circulation and to sketch a more realistic circulation pattern, the previous studies on the circulation are briefly reviewed and directly measured current data collected in the past are revisited. The Huanghai Sea Warm Current and the northeastward extension in summer of the Changjiang diluted water are paid more attention to, which are the major currents of the basic circulation, and then attempted to sketch the Huanghai Sea circulation by synthesizing hydrography and current data. The Huanghai Sea circulation is not considered to be persistent since the thin water column, less than 100 m, responds quickly and sensitively to external driving forces. Directly measured current data show that saline water originating from the Kuroshio water turns clockwise around Cheju-do throughout the year and eventually joins the Tsushima Warm Current at the western channel of the Korea Strait. This clockwise current is called the Cheju Warm Current. The current data do not support the persistent existence of the Huanghai Sea Warm Current, which has been believed to supply heat and salt to the Huanghai Sea throughout the year. However, a northward flow is generated intermittently during the weakening phase of cold air outbreaks in winter. The northeast extension of the Changjiang diluted water in summer is evidenced by satellite-tracked surface drifters.