A Note on Water Masses and General Circulation in the Yellow Sea (Hwanghae)

黃海水 와 循環에 관한 考察

  • Published : 1984.12.01

Abstract

Water masses and circulation in the yellow Sea (Hwanghae) were briefly reviewed and synthesized. Water masses were classified into four types: Hwanghae Cold Water, Hwanghae Warm Current Water, Coastal Waters and Changjiang River Diluted Water. The Hwanghae Cold Water can be defined to have a salinity of 32.0∼33.0% and a temperature below 10$^{\circ}C$, based on long-term hydrographic data and recent CTD casts (KORI, 1984). Concerning circulation, there exists a cyclonic gyre throughout the year in the southern part. In winter, the coastal current along the Chinese coast is very strong due to northerly or northwesterly winds and the Hwanghae Warm Current becomes weak as can be expected from a surface to bottom thermohaline front west of Cheju-do. Meanwhile in summer, the Changjiang River Diluted Water flows northeastward toward Cheju-do and the coastal current in the western part is greatly reduced. The northward current during summer in the southeastern Hwanghae has been accepted to be the Hwanghae Warm Current until now, coastal waters and the Hwanghae Cold Water in the central deep area, not a continuation of the Hwanghae Warm Current.

黃海에서 水塊와 循環에 대해 간략히 檢討, 討議하였다. 水塊는 黃海冷水, 黃海溫流水, 沿岸水, 陽子江 稀釋수 네가지로 分類된다. 黃海冷水는 長技 海洋觀測資料와 최근 CTD로 資料부터 32.0~33.0%의 鹽分, 1$0^{\circ}C$이하의 水溫을 갖고 있는 것으로 定義할 수 있다. 海水循環은 南部海域에서 年中 反時計方向의 海水循環이 存在한다. 겨울철에는 中國沿岸을 따라 南向하는 沿岸流流가 北風, 北西風으로 인해 强하게 나타나며 濟州道 西部 海域에 강한 水溫.鹽分前線이 잘 보여주듯 黃海暖流는 弱해진다. 반면에 여름철에는 陽子江 釋수가 濟州道 쪽을 향해 北東쪽으로 擴張하며 中國 沿岸流가 상당히 減少하게 된다. 지금 까지 여름철 東南黃海에서 北向流를 黃海暖流로 分類하였으나 류의 延長이 아니라 沿岸水와 黃海冷水사이 境界面을 따라 形成되는 密度流로 보는 것이 더욱 妥當하다.

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