| 摘要: |
| 台湾是我国第一大岛，其形略呈椭圆，长轴指向NNE，约长205海里(~380公里),短轴约80海里(~150公里)。台湾东临太平洋，海底地形峻陡，等深线大都与海岸平行，在离岸数十海里处，水深激增达4千米以上；西临台湾海峡，海底地形平坦，水深多在50-60米左右。
台湾东北角，在三貂角—苏澳以东，地形急变，等深线变成与海岸近乎正交而作ESE走向，水深从南北两侧的1000-2000米陡减为500米左右，最浅处尚不及200米。这就是本文中所提到的海脊。
台湾西南角，在高雄、恒春以西，等深线亦呈横斜状，水深自南向北锐减(图1)。
北赤道流在吕宋以北分为两支：东支即沿台湾东岸北上的黑潮主干，西支(黑潮分支)一部分进入南海，另一部分在夏季，又沿台湾西岸北上，后者在流出台湾海峡后，在台湾东北方与黑潮主干相会，“并肩地”流向东北(须田皖次，1948)。所以，可以认为，夏季，台湾是位于黑潮及其分支(以下或称东支及西支)的绕流之中。
北赤道流主轴在吕宋以东部分的流幅约45-90海里(85-170公里)(见Stommel及Yoshida，1972，第155页，图26a，b，c)，故台湾东西向的幅度约为北赤道流流幅的1.8-0.9倍。这样尺度的一个大岛，屹立在黑潮所流经的区域中，其影响显然是可观的。
关于台湾及其附近海底地形对黑潮途径的影响，过去还很少予以注意。本文拟从下列两方面，(1)台湾岛本身对黑潮的影响；(2)台湾附近海底地形对黑潮的影响，试作一些探讨。这些都是黑潮动力学中的重要问题，是黑潮的姊妹流——湾流所没有遇到的，值得深入研究。本文旨在着重提出这一问题，以期引起同行的注意，并进而解决这一问题。
本文所用资料均分别引自：(1)日本水产试验场，《海洋调查要报》，Nos. 44-69；(2)日本气象厅，《气象厅海洋气象观测资料》，Nos. 28-30，54。 |
| 关键词: 黑潮途径 海底地形 |
| DOI： |
| 分类号: |
| 基金项目:中国科学院海洋研究所调查研究报告第399号. |
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| THE TOPOGRAPHIC EFFECTS OF TAIWAN ISLAND, CHINA AND ADJACENT BOTTOM RELIEF ON THE PATH OF THE KUROSHIO |
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Kwan Ping-hsien
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Institute of Oceanology, Academia Sinica
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| Abstract: |
| Taiwan is the largest island of China. It faces the Pacific Ocean on the east where the bottom relief is very steep and most of the isobaths run parallel to the coast. At the places several tens of sea miles away from the coast, the depth increases abruptly to several thousands of meters. But at the northeastern corner, that is, to the east of Sandiao Jiao-Suao, there is an abrupt change in bottom topography, the isobaths are nearly perpendicular to the coast and run in the direction ESE, and the depth decreases rapidly from both the north and the south. Here is the submarine ridge as shown in Fig.1.
North of the Philippines，the North Equatorial Current is divided into two parts, the main current(the Kuroshio) flows northward along the east coast of Taiwan, while the branch, besides partly entering into the South China Sea, flows northwestward and then northeastward along the west coast of Taiwan in summer. Accordingly, it may be considered that Taiwan Island is situated in the circumfluence of the Kuroshio and its branch in summer.
The width of the main axis of the North Equatorial Current east of the Philippines is about 45 to 90 sea miles, and the east to west scale of Taiwan is about 80 sea miles, therefore, the latter is about 1.8 to 0.9 times as wide as the former. It goes without saying that, such a large island as the Taiwan Island，standing out against the flow pattern of the North Equatorial Current and the Kuroshio, must have a noticeable effect on the flow pattern of the Kuroshio.
In the present paper, the hydrographical data collected in the period from 1927- 1973 in the region near Taiwan Island were analyzed mainly by qualititative treatment in order to study the topographic effects of Taiwan Island and adjacent bottom relief on the path of the Kuroshio. |
| Key words: Topographic Path of the Kuroshio |
