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

Diserahkan: 15 Januari 2013 /Diterima: 3 Ogos 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

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*Pengarang untuk surat-menyurat; email: farshiddaryabor@gmail.com