Sains Malaysiana 43(3)(2014): 389–398

Simulation of Southwest Monsoon Current Circulation and Temperature in the East Coast of Peninsular Malaysia

(Simulasi Peredaran Arus dan Suhu Monsun Barat Daya di Perairan Pantai Timur Semenanjung Malaysia)

FARSHID DARYABOR*, FREDOLIN TANGANG & LIEW JUNENG

School of Environmental and Natural Resource Sciences, Faculty of Science and Technology

Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

Received: 15 January 2013 /Accepted: 3 August 2013

ABSTRACT

This study investigates the southwest monsoon circulation and temperature along the east coast of Peninsular Malaysia by using the Regional Ocean Modeling System at 9 km resolution. The simulated circulation shows strong northward flowing western boundary currents along the east coast of Peninsular Malaysia with maximum speed of approximately of 0.6-0.7 ms-1. The western boundary current, that extends to a depth of about 35 m, continues flowing northward up to approximately 7oN where it changes direction eastward. The circulation along the east coast of Peninsular Malaysia is also characterized by two anti-cyclonic eddies. Furthermore, an elongated of cooler sea surface temperature that stretches along the coast was also simulated. The existence of this cool SST pattern is associated with coastal upwelling process due to localized lifting of isotherms near the coast as a response to the southerly-southwesterly wind stress along the coast during the southwest monsoon.

Keywords: Coastal upwelling; current circulation; east coast of Peninsular Malaysia; Regional Ocean Modeling System; western boundary current

ABSTRAK

Kajian ini mengkaji peredaran arus dan suhu di pesisir laut pantai timur Semenanjung Malaysia dengan menggunakan Sistem Model Laut Serantau pada resolusi 9 km. Peredaran arus yang disimulasi menunjukkan arus sempadan barat yang kuat mengalir ke utara sepanjang pesisir pantai Semenanjung Malaysia dengan kelajuan maksimum 0.6 - 0.7 ms-1. Arus sempadan barat yang mencapai kedalaman sehingga 35 m, mengalir ke utara sehigga ke latitud 7oU sebelum ia bertukar arah ke timur. Peredaran sepanjang pesisir pantai Semenanjung Malaysia juga dicirikan oleh dua pusar anti-siklon. Selain itu terdapat kawasan memanjang bersuhu permukaan laut yang rendah sepanjang pesisir laut pantai. Kewujudan kawasan bersuhu rendah ini adalah berkaitan dengan proses pengaliratasan akibat pengangkatan isoterma berhampiran pesisir pantai sebagai respon kepada tegasan angin barat daya semasa musim monsun barat daya.

Kata kunci: Arus sempadan barat; pengaliratasan pesisir pantai; perederan arus; pesisir pantai timur Semenanjung Malaysia; Sistem Model Laut Serantau

REFERENCES

Akhir, M.F. & Chuen, Y.J. 2011. Seasonal variation of water characteristics during inter-monsoon along the east coast of Johor. Journal of Sustainability Science and Management 6(2): 206-214.

Akhir, M.F. 2012. Surface circulation and temperature distribution of southern South China Sea from global ocean model (OCCAM). Sains Malaysiana 41(6): 701-714.

Chu, P.C., Lu, S. & Chen, Y. 1997. Temporal and spatial variabilities of the South China Sea surface temperature anomaly. Journal of Geophysical Research 102: 20937- 20955.

Chu, P.C., Edmons, N.L. & Fan, C.W. 1999. Dynamical mechanisms for the South China Sea seasonal circulation and thermohaline variability. Journal of Physical Oceanography 29: 2971-2989.

Cai, S., Su, J., Long, X., Wang, S. & Huang, Q. 2005. Numerical study on summer circulation and its establishment of the upper South China Sea. Acta Oceanologica Sinica 24(1): 31-38.

Cai, S.Q., Long, X. & Wang, S. 2007. A model study of the summer Southeast Vietnam offshore current in the southern South China Sea. Continental Shelf Research 27: 2357-2372.

Carton, J.A. & Giese, B.S. 2008. A reanalysis of ocean climate using simple ocean data assimilation (SODA). Monthly Weather Review 136: 2999-3017.

Dale, W.L. 1956. Wind and drift current in the South China Sea. The Malayan Journal of Tropical Geography 8: 1-31.

Da Silva, A.M., Young, C.C. & Levitus, S. 1994.  Atlas of Surface Marine Data. Vol. 1. Algorithms and Procedures, NOAA Atlas NESDIS 6, U.S. Department of Commerce, NOAA, NESDIS, USA.

Fang, G.H., Gang, W., Yue, F. & Wendong, F. 2012. A review on the South China Sea western boundary current. Acta Oceanologica Sinica 31(5): 1-10.

Gill, A.E., Green, J.S.A. & Simmons, A.J. 1974. Energy partition in the large-scale ocean circulation and the production of mid-ocean eddies. Deep Sea Research 21: 499-528.

Gan, J., Li, H., Curchitser, E.N. & Haidvogel, D.B. 2006. Modeling South China Sea circulation: Response to seasonal forcing regimes. Journal of Geophysical Research: Oceans. 111: C6.

Hu, J.Y., Kawamura, H., Hong, H. & Qi, Y.Q. 2000. A review on the currents in the South China Sea: Seasonal circulation, South China Sea warm current and Kuroshio intrusion. Journal of Oceanography 56: 607-624.

Hu, J.Y., Gan, J., Sun, Z., Zhu, J. & Dai, M. 2011. Observed three-dimensional structure of a cold eddy in the Southwestern South China Sea. Journal of Geophysical Research: Oceans. 116: C5.

Li, R.F., Zeng, Q.C., Ji, Z.Z. & Guan, D. 1992. Numerical simulation for a northeastward flowing current from area off the eastern Hainan Island to Tsugaru/Soya Strait. La mer 30: 229-238.

Liu, Z. & Yang, H. 2001. Regional dynamics of seasonal variability in the South China Sea. Journal of Physical Oceanography 31: 272-284.

Locarnini, R.A., Mishonov, A.V., Antonov, J.I., Boyer, T.P. & Garcia, H.E. 2006. World Ocean Atlas 2005, Volume 1: Temperature. S. Levitus, Ed. NOAA Atlas NESDIS 61. Washington, D.C.: U.S. Government Printing Office.

Morimoto, A., Yoshimoto, K. & Yanagi, T. 2000. Characteristics of sea surface circulation and eddy field in the South China Sea revealed by satellite altimetric data. Journal of Oceanography 56: 331-344.

Marchesiello, P., McWilliams, J.C. & Shchepetkin, A. 2001. Open boundary condition for long-term integration of regional oceanic models. Ocean Modeling 3: 1-21.

Pohlmann, T. 1987. A three-dimensional circulation model of the South China Sea. In Three-Dimensional Models of Marine and Estuarine Dynamics, edited by Nihoul, J. & Jamart, B. USA: Elsevier Science.

Penven, P., Marchesiello, P., Debreu, L. & Lefevre, J. 2008. Software tools for pre-and post-processing of oceanic regional simulations. Journal of Environmental Modelling and Software 23: 660-662.

Qu, T. 2000. Upper-layer circulation in the South China Sea. Journal of Physical Oceanography 30: 1450-1460.

Qu, T. 2001. Role of ocean dynamics in determining the mean seasonal cycle of the South China Sea surface temperature. Journal of Geophysical Research 106(C4): 6943-6955.

Qiu, B. & Chen, S. 2005. Eddy-induced heat transport in the subtropical North Pacific from Argo, TMI, and Altimetry measurements. Journal of Physical Oceanography 35: 458-473.

Reynolds, R.W., Smith, T.M., Liu, C., Chelton, D.B., Casey, K.S. & Schlax, M.G. 2007. Daily high-resolution blended analyses for sea surface temperature. Journal of Climate 20: 5473-5496.

Shaw, P.T. & Chao, S.Y. 1994. Surface circulation in the South China Sea. Deep-Sea Research I 40(11/12): 1663-1683.

Shen, S. & Lau, K.M. 1995. Biennial oscillation associated with the East Asian summer monsoon and tropical sea surface temperature. Journal of Meteorological Society of Japan 73: 105-124.

Smith, W.H.F. & Sandwell, D.T. 1997. Global seafloor topography from satellite altimetry and ship depth soundings. Science 277: 1957-1962.

Tomita, T. & Yasunari, T. 1996. Role of the northeast winter monsoon on the biennial oscillation of the ENSO/monsoon system. Journal of Meteorological Society of Japan 74: 399-413.

Tangang, T.F., Xia, C., Qiao, F., Juneng, L. & Shan, F. 2011. Seasonal circulations in the Malay Peninsula Eastern continental shelf from a wave–tide–circulation coupled model. Ocean Dynamics 61(9): 1317-1328.

Wyrtki, K. 1961. Scientific results of marine investigations of the South China Sea and the Gulf of Thailand 1959–1961. Naga Report 2.

Wang, B., Huang, F., Wu, Z., Yang, J., Fu, X. & Kikuchi, K. 2009. Multi-scale climate variability of the South China Sea monsoon: A review. Dynamics of Atmospheres and Oceans 47: 15-37.

Xie, S.P., Xie, Q., Wang, D.X. & Liu, W.T. 2003. Summer upwelling in the South China Sea and its role in regional climate variations. Journal of Geophysical Research 108: C8.

Yaocun, Z. & Qian, Y. 1999. Numerical simulation of the regional ocean circulation in the coastal areas of China. Advances in Atmospheric Sciences 16(3): 443-450.

Yanagi, T., Sachoemar, I.S., Takao, T. & Fujiwara, S. 2001. Seasonal variation of stratification in the Gulf of Thailand. Journal of Oceanography 57: 461-470.

*Corresponding author; email: farshiddaryabor@gmail.com