臺灣四周海域的水深地形變化複雜，同時東岸外海有洋流黑潮通過，地形與洋流導致臺灣近岸海流呈現複雜多變的情況。若能瞭解臺灣四周海域海流之變化，將可作為海洋及海岸等諸多相關活動的發展與應用之重要參考依據。例如，桃園沙崙外海卸油浮筒為中油進口油品重要的裝卸站，發生溢洩油的風險很大。另外，臺灣海域為東亞航運必經之地，對外航運十分頻繁，且冬天期間受到強烈東北季風的影響，大型船舶發生擱淺與溢洩油的機率會增高。若海岸地區發生溢洩油事件，將嚴重影響港灣及近岸區域的環境生態，有鑑於此，建置ㄧ套近岸海流預測模式有其必要性。
本研究應用一套三維跨尺度的海洋數值模式SCHISM，預測桃園沙崙及新北市石門外海近岸海流演變之現象，並以實測海水位及海流資料與SCHISM模式預測結果進行比對及驗證。SCHISM輸入邊界條件，開放邊界的初始海象條件取自於HYCOM模式模擬之水表面高度、海流速度、海面溫度及鹽度等資料，計算區域海表面初始氣象資料取自美國 NECP-CFSv2 氣象模式或中央氣象局WRF氣象模式的海表面風速、氣壓、氣溫、比溼度、長短波輻射以及表面降雨率等。
SCHISM預測海水位及海流流速與實測資料比對結果顯示，SCHISM模式除可以準確預測海水位變化，在海流預測部份，SCHISM預測結果與科技部國家實驗研究院台灣海洋科技中心的高頻雷達CODAR實測海流流速資料在時序列變化趨勢也呈現非常一致的結果，由互相關性分析結果分析顯示，僅2016年7月沙崙外海的T-P3位置海流流速預測與實測時間序列資料有1小時相位差外，其他位置比對皆無相位差。由預測與實測海流流速資料相關性分析結果顯示，在兩個研究案例中，預測與實測海流流速的相關程度在沙崙外海T-P1、T-P2及石門外海的S-P2、S-P3屬於高度線性相關，相關係數達0.7以上，而T-P3與S-P1屬於中度線性相關，相關係數介於0.4至0.7。綜合上述結果可知，SCHISM預測海流資料可以描述近岸海流變化的趨勢，且具有高度的參考價值，未來也能提供油污染擴散模式或其他海洋污染擴散模式之應用。

In order to reveal the characteristics of the nearshore current around Taiwan, this study used a cross-scale unstructured grid ocean model SCHISM to simulate the nearshore currents in the Shalun (Taoyuan City) and Shimen (New Taipei City) coasts. In this study, we compared the simulated and observed field currents to assess how well the model reproduces the existing dynamics. The observed current data were collected from CODAR (HF radar) and the observed sea surface elevations were collected from the tidal stations in the Shalun and Shimen coasts.
Comparison of the predicted and observed sea surface elevations shows that the predicted time series of the water elevation in the Shalun and Shimen coasts are consistent with the observed ones. Comparison of the simulated and observed surface current velocities shows that the simulated time series of the current velocities in the Shalun and Shimen coasts are in close agreement with the observed data.
The cross correlation analysis for the simulated and observed current velocities indicate that only at the T-P3 position during July 1-31, 2016, there was an hour time-lag between the predicted and observed current velocities. At other positions both values agree with each other very well. The correlation coefficients for the current velocity between the model and COADR data show that at the T-P1 and T-P2 positions (in Shalun) and the S-P2 and S-P3 positions (in Shimen) the simulated current velocities are highly correlated with the observed ones, while at the T-P3 position (in Shalun) and the S-P1 position (in Shimen) both are moderately correlated. The above-mentioned results demonstrate that the SCHISM model can be used to simulate the sea surface elevations and nearshore currents, and the results are of highly reference value. The forecasted sea surface elevations and current velocities will be required for the numerical simulation of oil spilling.

[1] Benque, J. P. J. A. F. J. H. A. a. H. F. M., “New method for tidal current computation,” J. Wtrwy., Port, Coast and Oc. Div, ASCE, vol.108, pp. 396-417, 1982.
[2] Blain, C.A., Preller, R.H., Rivera, A.P, “Tidal prediction using the advanced Circulation Model (ADCIRC) and a Relocatable PC-based System,” Oceanography, vol.15, pp. 77-87, 2002.
[3] Blain, C.A., Westerink, J.J., Luettich, R.A., “The influence of domain size on the response characteristics of a hurricane storm surge model,” Journal of Geophysical Research, vol.99, pp. 18467-18479, 1994.
[4] Blumberg, A.F., Mellor, G.L., “A description of a three-dimensional coastal ocean circulation model, Three-Dimensional Coastal Ocean Models,” American Geophysical UnionWashington,DC, pp. 1-16, 1987.
[5] Booij, N., Ris, R. C., Holthuijsen, L. H., “A third-generation wave model for coastal regions, Part I, Model description and validation,” J. Geophys. Res, pp. 7649-7666, 1999.
[6] Canuto, V. H. A. C. Y. D. M., “Ocean turbulence I: one-point closure model. Momentum and heat vertical diffusivities.,” J. Phys. Oceanogr, 第31冊, p. 1413–1426., 2001.
[7] Casulli, V. Z. P., “High resolution methods for multidimensional advection–diffusion problems in free-surface hydrodynamics,” Ocean Model, vol.10, pp. 137–151, 2005.
[8] Chen, C., Liu, H., Robert, C. Beardsley, “An Unstructured Grid, Finite-Volume, Three-Dimensional, Primitive Equations Ocean Model: Application to Coastal Ocean and Estuaries,” JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY, pp. 159-186, 2003.
[9] Chen, C. B. R. C. a. C. G., “An unstructured grid,finite-volume coastal ocean model (FVCOM) system,” OCEANOGRAPHY-WASHINGTON DC-OCEANOGRAPHY SOCIETY, vol.19, pp. 78, 2006.
[10] Chen, C., Liu, H., Beardsley, R. C., “An unstructured, finite-volume three-dimensional, primitive equation ocean model: application to coastal ocean and estuaries,” Journal of Atmospheric and OceanicTechnology, vol.20, pp. 159-186, 2003.
[11] Chen, C., B., Robert, C., Richard, L., Kuh, K., “Comparison of winter and summer hydrographic observations in the Yellow and East China Seas and adjacent Kuroshio during 1986,” Continental Shelf Research, vol.14, pp. 909-929, 1994.
[12] Chen, C., Qi, J., Li, C.,Robert, C., Beardsley , “Complexity of the flooding/drying process in an estuarine tidal-creek salt-marsh system: An application of FVCOM,” JGR, 2008.
[13] Clayson, L. H. K. A., Numerical Models of Oceans and Oceanic Processes, 2000.
[14] David, W. C., Turbulence Modeling for CFD, second edition, La Canada, California: DCW industries Inc, 1998.
[15] Rabiner, L.R., Schafer, R.W., “Digital Processing of Speech Signals. Signal Processing Series”, Upper Saddle River, NJ: Prentice Hall. pp. 147–148, 1978.
[16] Dietrich, J.C., Zijlema, M., Westerink, J.J., Holthuijsen, L.H., Dawson, C.N., LuettichJr., R.A., Jensen, R.E., Smith, J.M., Stelling, G.S., Stone, G.W., “Modeling Hurricane Waves and Storm Surge using Integrally-Coupled, Scalable Computations,” Coastal Engineering, vol.58, pp. 45-65, 2011.
[17] Galperin B. K. L. H. S. R. A., “A quasiequilibrium turbulent energy model for geophysical flows,” J. Atmos. Sci, vol.45, pp. 55-62, 1988.
[18] Hsu,T.W., Ou,S.H., Liau, J.M., “Hindcasting nearshore wind wave using a FEM code for SWAN,” Coatal Engineering, vol.52, pp. 177-195, 2005.
[19] Kantha, L. C. C., “An improved mixed layer model for geophysical applications,” J. Geophys. Res, vol.99, pp. 235–266, 1994.
[20] Kumar, N. V. G. W. J. a. M. O., “Implementation of a vortex force formalism in a coupled modeling system for inner-shelf and surf-zone applications,” Ocean Modelling, vol.47, pp. 65-95, 2012.
[21] Liu ,B., Liu H., and Xie L., “A Coupled Atmosphere–Wave–Ocean Modeling System: Simulation of the Intensity of an Idealized Tropical Cyclone,” MONTHLY WEATHER REVIEW, vol.139, pp. 132-152, 2010.
[22] Luettich, R. J. S. H. J. W. a. N. S., “Modeling 3-D Circulation Using Computations for the Western North Atlantic and Gulf of MexicoEstuarine and Coastal Modeling II,” M. Spaulding [ed.], ASCE, pp. 632-64, 1992.
[23] Luettich, R.A., Westerink, J.J., “A solution for the vertical variation of stress, rather than velocity, in a three-dimensional circulation mode,” International Journal for Numerical Methods in Fluid, vol.12, pp. 911-928, 1991.
[24] Lyard, F. L. F. L. T., “Modelling the global ocean tides modern insights from FES2004,” Ocean Dynamics, vol.56, pp. 394-415, 2006.
[25] Mellor, G.L., Yamada, T., “Development of a turbulence closure model for geophysical fluid problems,” Rev. Geophys, vol.20, pp. 851-875, 1982.
[26] Oliveira, A. B. A., “On the role of tracking on Eulerian–Lagrangian solutions of the transport equation,” Adv. Water Res, vol.21, pp. 539–554., 1998.
[27] Phillips, N.A, “A Coordinate System Having Some Special Advantages For Numerical Forecasting,” American Meterological Society, vol.14, pp. 184-185, 1957.
[28] Qi, J. C., Chen, R. C., Beardsley, W. Perrie and G. Cowles, “An unstructured-grid finite-volume surface wave model,” Ocean Modelling, vol.28, pp. 153-166, 2009.
[29] Rabiner, L., Schafer, R., “Digital Processing of Speech Signals.,” Signal Processing Series. Upper Saddle River, NJ, pp. 147-148, 1978.
[30] Rodi, W., “Turbulence models and their applications in hydraulics: a state of the art review,” International Association for Hydraulics Research, 1984.
[31] Shchepetkin, A. F. a. M. J. C., “The regional oceanic modeling system (ROMS): a split-explicit, free-surface,” 2005.
[32] Sikiric, M. D., Roland, A., Janeković, I., Kuzmić, M., “Coupling of the Regional Ocean Modeling System (ROMS) and Wind Wave Model,” Ocean Modeling, pp. 59-73, 2013.
[33] Song, Y. a. H. D., “A semi-implicit ocean circulation model using a generalized topography-following coordinate system,” J.Compt.Phys, pp. 228-244, 1994.
[34] Song, Y., Haidvogel, D. B., “A semi-implicit ocean circulation model using a generalized topography-following coordinate system,” J. Comp. Phys., pp. 228-244, 1994.
[35] Umlauf, L., Burchard, H, “A generic length-scale equation for geophysical turbulence models,” J. Mar. Res, vol.6, pp. 235-365, 2003.
[36] Warner, J. P. N. S. E., “Using the Model Coupling Toolkit to couple earth system models,” Environmental Modelling and Software, vol.23, pp. 1240-1249, 2008.
[37] Zhang, Y. J., A. M. B. E. P. M., “A cross-scale model for 3D baroclinic circulation in estuary–plume–shelf systems: I. Formulation and skill assessment,” Continental Shelf Research, vol.24 , pp. 2187-2214, 2004.
[38] Zhang, Y., Ateljevich E., Yu H. C., Wu C. H.,Yu J. C.S, “A new vertical coordinate system for a 3D unstructured-grid model,” Ocean Modelling, vol.85, pp. 16-31, 2015.
[39] Zhang, Y., Baptista, A.M, “SELFE: a semi-implicit Eulerian–Lagrangian finite-element model for cross-scale ocean circulation,” Ocean modeling, vol.21, pp. 71-96, 2008.
[40] Zhang, Y., Ye, F., Stanev, E.V., Grashorn, S, “Seamless cross-scale modeling with SCHISM,” Ocean Modelling, vol.21, pp. 71-96, 2016.
[41] Zheng, Q., Fang, G., Song, Y. T., “Introduction to special section: Dynamics and Circulation of the Yellow East, and South China Seas,” Journal of Geophysical Research , 2006.
[42] 于嘉順，三維海流預報作業模式建置及校驗分析研究，交通部中央氣象局, 2010。
[43] 于嘉順，大鵬灣水域生態環境數值監控管理模式建置研究延續計畫，交通部運輸研究所港灣技術研究中心，2010。
[44] 方盈智、王冑、楊穎堅、郭天俠、唐存勇，運用高頻雷達觀測臺灣東北海域表面海流及其資料品質與準確性之探討，101 年天氣分析與預報研討會，2012。
[45] 王胄、楊穎堅、郭天俠、王弼、鍾育仁、崔怡楓、梁文德，臺灣東北部海域高頻雷達測流經驗談，2015
[46] 李宗勇，臺灣東部高頻雷達表面海流觀測之資料品質管理與初步結果，2015。
[47] 孔俊，非結構型淺水方程數值模式的應用與建立，2006。
[48] 吳朝榮，黑潮洋流(一)，2004。
[49] 邱啓敏、黃清哲、莊士賢、范揚洺、吳立中、邱永芳、蘇青和，「德翔臺北」貨輪擱淺事件應用SCHISM模擬溢油之擴散，第 38 屆海洋工程研討會暨科技部計畫成果發表會論文集， 2016。
[50] 莊士賢、吳立中、范揚洺、邱啟敏、蘇青和、李俊穎、黃瓊珠，海域油污監測與擴散模擬技術研發(3/3)，交通部運輸研究所港灣技術研究中心，2017.
[51] 莊士賢、吳立中、范揚洺、簡仲璟、李俊穎、余孟娟、陳家銘、饒國清、邱啟敏、林清睿、黃瓊珠，海域油污監測與擴散模擬技術研發(1/3)，交通部運輸研究所港灣技術研究中心，2015。
[52] 莊士賢、吳立中、范揚洺、簡仲璟、李俊穎、余孟娟、陳家銘、饒國清、邱啟敏、林清睿、黃瓊珠，海域油污監測與擴散模擬技術研發(2/3)，交通部運輸研究所港灣技術研究中心，2016。
[53] 陳偉柏 、柳文成、許銘熙、于宜強，台灣海峽暴潮位數值模擬之研究，第32 屆海洋工程研討會論文集， 2010。
[54] 廖建明、許泰文、石棟鑫、杜佳穎、陳俊文、莊文傑， POM 海洋數值模式應用於臺灣，交通部運輸研究所港灣技術研究中心，2010。
[55] 董東璟、蔡政翰、 陳盈智、顏志偉、馬名軍，應用岸基微波雷達量測近岸海流空間分布，航測及遙測學刊，第18卷，第 3 期，第193-204頁，2014。