Coastal currents consist of wind-driven, tidal, surface wave and geostrophic flows. These currents have a major role for nearshore sediment transport, but the measured data availability on coastal currents for the Indian coast is relatively less. This study analyze the variability of coastal currents along with the tides at nearshore and offshore waters during two different seasons (fag end of summer monsoon and initial stage of pre-monsoon) at Vengurla, west coast of India. Results of this study exhibited that the tides at Vengurla are mixed semi-diurnal dominated by solar constituent during summer monsoon (September to October); whereas the lunar constituents dominates during pre-monsoon (February to March). The nearshore current was dominated by the westward flow (sluggish current) during monsoon and south eastward flow during pre-monsoon, whereas the offshore flow (strong current) showed seasonality. At offshore, southerly current dominated during summer monsoon, whereas the northerly current played a major role during pre-monsoon. The current profile analysis at offshore revealed that the gradation of strong current at the surface to the sluggish nature of currents at the bottom and were comparatively higher during summer monsoon than pre-monsoon periods. This study revealed a complex pattern among winds, tides and currents at offshore.

中文翻译：

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印度西海岸文古拉热带沿海水域中与潮汐和风相关的海岸流案例研究

海岸流包括风驱动、潮汐、表面波和地转流。这些洋流在近岸沉积物运输中起着重要作用，但印度海岸沿岸洋流的测量数据可用性相对较少。本研究分析了印度西海岸文古拉 (Vengurla) 两个不同季节 (夏季季风末期和季风前期初期) 的近岸和近海水域沿海洋流随潮汐的变化。研究结果表明，在夏季风期间（9-10 月），文古拉潮汐呈混合半日潮，以太阳成分为主；而月球成分在季风前（2 月至 3 月）占主导地位。近岸流以季风时西流（滞流）为主，季风前期以东南流为主，而离岸流（强流）则表现出季节性。在近海，夏季风以南风为主，季风前期以北风为主。近海洋流剖面分析表明，夏季风期与季风前期相比，地表强水流与底部水流缓慢性质的梯度相对较高。这项研究揭示了近海风、潮汐和洋流之间的复杂模式。近海洋流剖面分析表明，夏季风期与季风前期相比，地表强水流与底部水流缓慢性质的梯度相对较高。这项研究揭示了近海风、潮汐和洋流之间的复杂模式。近海洋流剖面分析表明，夏季风期与季风前期相比，地表强水流与底部水流缓慢性质的梯度相对较高。这项研究揭示了近海风、潮汐和洋流之间的复杂模式。