本文以美國普林斯頓海洋模式 POM (Princeton Ocean Model)為基礎，建置台灣環島海域三維海潮流模擬系統，以巢狀網格縮小計算範圍至台灣南部之南灣海域。將格網間距調整至500m(約1/200°)，利用高解析度之計算技巧來模擬南灣海域潮流與溫度的變化，同時模擬呂宋海峽之內潮機制，即正壓潮轉為斜壓潮(內潮)能量(barotropic　to baroclinic tidal energy conversion)。根據模擬結果，進一步的探討南灣海域湧升流(upwelling)冷水出現之機制。由平面及垂直剖面之溫度與潮流模擬結果可知，南灣海域溫降現象於大潮期間較為顯著，在退潮時，南灣海域的潮流流速則逐漸的增強，同時當地潮流因受到模擬區域內海底山以及恆春海脊地形的影響，在灣內衍生逆時針渦流。本文斜壓潮能量通率計算結果顯示，在恆春海脊北端有明顯強烈向西傳遞的斜壓潮能量通率產生，且此能量通量在傳遞至南灣海域後繼續往台灣西南海域移動，在南灣海域內部產生擾動，導致深海冷水湧升至南灣淺水區，造成南灣海域海水溫度突降的現象。與沒有黑潮時的斜壓潮能量通率相比較，在恆春海脊北端產生的斜壓潮能量通率有減弱趨勢，且會影響南灣沿岸溫度變化。

In this study, a three-dimensional ocean current model　around Taiwan is developed　using POM (Princeton Ocean　Model). The model was applied to construct the　three-dimensional model for simulating ocean current around Taiwan coastal waters. The　nested domain was adopted to narrow the computational region to the southernmost coastal　waters of Nanwan Bay at Taiwan. A higher-resolution model with spatial grid of 500m(1/200 degree), was used to simulate the　distribution of current and temperature in the　Nanwan Bay and baroclinic tidal energy flux in the Luzon Strait. The　barotropic-to-baroclinic (bt-to-bc) tidal energy conversion rate and bc tidal energy fluxes　were further analyzed and was used to locate the generation site of internal tides in the　Luzon Strait. From simulation results, we further study the cold water of upwelling at　Nanwan Bay. The results show that the sudden temperature drops occurred more　significantly during spring tides at Nanwan Bay. Inside the Bay, the current forms a　counter clockwise vortex because of the topographic effect during the ebb tide. The results
of the baroclinic tidal energy flux show that the baroclinic tidal is generated from the　eastern flank of Heng-Chun Ridge, and there is a strong energy flux area which seems to
be a source of the baroclinic tidal westward propagating into the Bay. The upwelling of　cold water due to the baroclinic tidal propagating from the Heng-Chun Ridge causes the　temperature drops. Comparing with the baroclinic tidal energy flux without the Kuroshio’s　influence, the energy flux can reduce the temperature variations.

1. Blumberg, A.F. and Mellor, G.L., “A description of a three-dimensional coastal ocean circulation model,” Three-Dimensional Coastal Ocean Models, American Geophysical Union, Washington, D.C., 4, edited by N. Heaps, 208p (1987)
2. Centurioni, L.R., Niiler, P.P. and Lee, D.K., “Observations of Inflow of Philippine Sea Surface Water into the South China Sea through the Luzon Strait” Journal of Physical Oceanography, Vol. 34, pp. 113-121 (2004)
3. Chen, C.T.A., Hsing, L.Y., Liu, C.L. and Wang, S.L., “Degree of nutrient consumption of upwelled water in the Taiwan Strait based on dissolved organic phosphorus or nitrogen,” Marine Chemistry, 87, pp. 73-86 (2004)
4. Fan, K.L. and Yu, C.Y., “A study of watermasses in the seas of southernmostTaiwan”, ACTA Oceanographica Taiwanica, No. 12, pp. 94-111 (1981)
5. Garrett,C., “Internal tides and ocean mixing”, Ocean Science,Vol. 301, pp. 1858-1859 (2003)
6. Hsu, M.K., Liu, A.K., and Liu, C., “A study internal waves in the China Seas and Yellow Sea using SAR”, Continental Shelf Research, Vol. 20, pp. 389-410 (2000)
7. Jan, S., Chen, C.T.A., Tu, Y.Y. and Tsai, H.S., “Physical properties of thermal plumes from a nuclear power plant in the southernmost Taiwan”, Journal of Marine Science and Technology, 12, 5, pp. 1-9 (2004)
8. Jan, S. and Chen, C.T.A “Potential biogeochemical effects from vigorous internal tides generated in Luzon Strait: A case study at the southernmost coast of Taiwan,” Journal of geophysical research, Vol. 144, pp. 1-14 (2009)
9. Jan, S., Chern, C.S., Wang, J., and Chiou, M.D., “Generation and propagation of baroclinic tides modified by the Kuroshio in the Luzon Strait”, Journal of Geophysical Research, Vol. 117, C02019 (2012)
10. Kunze, E., Rosenfield, L., Carter, G.S. and Gregg, M.C. “Internal waves in Monterey submarine canyon”, Journal of Physical Oceanography, Vol. 32, pp. 1890–1913 (2002)
11. Lee, H.J., Chao, S.Y., Fan, K.L., Wang, Y.H. and Liang, N.K. “Tidally induced upwelling in a semienclosed basin：Nan Wan bay,” Journal of Oceanography., Vol. 53, pp. 467-480 (1997)
12. Lee, H.J. Chao, S.Y., and Fan, K.L. “Flood-ebb disparity of tidally Induced recirculation eddies in semi-enclosed basin: Nan Wan Bay”, Continental Shelf Research, 19, pp. 871- 890 (1999a)
13. Lee, H.J., Chao, S.Y., Fan, K.L. and Kuo, T.Y. “Tide-induced eddies and upwelling in a semi-enclosed basin:Nan Wan,” Estuarine, Coastal and Shelf Science, Vol. 49, pp. 775-787 (1999b)
14. Li, H.W. “A numerical predicative model of tides in the seas adjacent to Taiwan,” Proceedings of National Science Council, Part A:Physical Science and Engineering, Vol. 11 (1), pp. 74-89 (1987)
15. Liang, N.K., Lein, S.L., Chen, W.C. and Chang, H.T. “Oceanographic investigation in the vicinity of Ma-An-San and Nan Wan bay,” Special publication No. 18 ,National Taiwan Univ., pp. 207 (1978)
16. Liu, C.S., Liu, S.Y., Lallemand, S.E., Lundberg, N. and Reed, D., “Digital Elevation Model Offshore Taiwan and Its Tectonic Implications,” TAO, 9 (4), pp. 705-738 (1998)
17. Madala, R.V. and Piacsek, S.A., “A semi-implicit numerical model for baroclinic oceans,” Journal of Computational Physics., 23, pp. 167-178 (1977)
18. Matsumoto, K., Takanezawa, T. and Ooe, M., “Ocean tide models developed by assimilating TOPEX/POSEIDON altimeter data into hydrodynamical model: A global model and a regional model around Japan,” Journal of Oceanography., 56, pp. 567-581 (2000)
19. Mellor, G.L., Users guide for a three-dimensional, primitive equation, numerical ocean model, Program in Atmospheric and Oceanic Sciences, Princeton University, Princeton (2003)
20. Mellor, G.L. and Yamada, T., “Development of a turbulence closure model for geophysical fluid problems,” Reviews of Geophysics and Space Physics., Vol. 20, pp. 851-875 (1982)
21. Oey, L.Y., Mellor, G.L. and Hires, R.I., “A three-dimensional simulation of the Hudson-Raritan estuary, Part I: Description of the model and model simulations,” Journal of Physical Oceanography, Vol. 15, pp. 1676-1692 (1985a).
22. Oey, L.Y., Mellor, G.L. and Hires, R.I., “A three-dimensional simulation of the Hudson-Raritan estuary, Part II: Comparison with observation,” Journal of Physical Oceanography, Vol. 15, pp. 1693-1709 (1985b)
23. Phillips, N.A., “A coordinate system having some special advantages for numerical forecasting”, Journal of Meteorology, Vol. 14, pp. 184-185 (1957)
24. Siegel, D.A., McGillicuddy, D.J.Jr and Fields, E.A., “Mesoscale eddies, satellite altimetry and new production in the Sargasso Sea”, Journal of Geophysical Research, Vol. 104, pp. 13359-13379 (1999)
25. Simons, T.J., “Verification of numerical models of Lake Ontario. Part I, ciculation in spring and early summer,” Journal of Physical Oceanography, Vol. 4, 507-523 (1974)
26. Smagorinsky, J., Manabe, S., and Holloway, J.L., “Numerical results from a nine-level general circulation model of the atmosphere,” Monthly Weather Review, Vol. 93, pp. 727-768 (1965)
27. Su, J.C., Hung, T.C. Chiang, Y.M. Tan, T.H. Chang, K.H. Shao, K.T. Hwang, P.P. Lee, K.T. Huang, C.C. Huang, C.Y. Fan, K.L. and Yeh, S.Y. “An ecological survey on the waters adjacent to the nuclear power plant in southern Taiwan”, Special publication No. 70, National Scientific Committee on Problems of the Environment, Academia Sinica, Taipei, Taiwan, ROC, 238 pp (1989)
28. Wang, Y.H., Dai, C.F. and Chen, Y.Y., “Physical and ecological processes of internal waves on an isolated reef ecosystem in the South China Sea”, Geophysical Research Letters, Vol. 34, L18609, (2007)
29. 謝孟松，”南灣海域潮汐渦漩特性之研究”，國立台灣海洋大學海洋環境資訊所碩士論文，(2008)
30. 吳瑞中，張育嘉，姚建中，曾若玄，陳冠宇，”南灣週期性冷水效應的數值及實測研究”，第三十二屆海洋工程研討會論文集，55頁-60頁，(2010)