Sains Malaysiana 39(4)(2010): 519–524

Currents Simulation in the Malacca Straits by Using Three-Dimensional Numerical Model

(Simulasi Arus di Selat Melaka Menggunakan Model Berangka Tiga Dimensi)

Syamsul Rizal¹*, Ichsan Setiawan¹, Taufiq Iskandar², Yopi Ilhamsyah¹, Mulyadi A.Wahid³ & Musri Musman¹

¹Marine Sciences Departement

Coordinatorate of Ocean and Fisheries

Syiah Kuala University, Jl. Putroe Phang, Darussalam

Banda Aceh, 23111, Indonesia, Darussalam

²Mathematics Department

Faculty of Mathematics and Natural Sciences

Syiah Kuala University, Jl. Syekh Abdul Rauf, Darussalam, Banda Aceh, 23111, Indonesia

³Center for Marine and Fishery Studies

Syiah Kuala University, Jl. Syekh Abdul Rauf, Darussalam, Banda Aceh, 23111, Indonesia

Received: 7 October 2009 / Accepted: 21 January 2010

Abstract

The Malacca Straits is located between Peninsula Malaysia and Sumatra Island. This investigation used equation of motion (Navier-Stokes equation) with the following driving forces: tides, wind of National Centers for Environmental Prediction (NCEP) for year of 2007, salinity and temperature. The equation of motion was solved by means of Hamburg Shelf Ocean Model (HAMSOM). The results for both southwest and northeast monsoon were explained and discussed. The simulation results both for February and August 2007 were relatively similar. Current surface simulation in the Malacca Straits agrees well with the current pattern of previous works. The magnitude of current was between 10-70 cm/s to the northwest. While at the layer 30-50 m in the Malacca Straits, the currents have the magnitude of 10-30 cm/s towards northwest. For the bottom current, the current speed was 0-20 cm/s towards northwest. For the surface and 30-50 m layer, generally the current magnitudes were greater in February compared to those in August. While for the bottom layer, the current magnitudes between February and August were relatively the same.

Keywords: Baroclinic current; Malacca Straits; northeast monsoon; southwest monsoon

ABSTRAK

Selat Melaka terletak di antara Semenanjung Malaysia dan Pulau Sumatera. Kajian ini menggunakan persamaan gerakan (Navier-Stokes) bersama daya pemacu berikut: air pasang-surut, data angin dari Pusat Kebangsaan Ramalan Sekitaran bagi tahun 2007, saliniti dan suhu. Persamaan gerakan diselesaikan menggunakan Model Lautan Pelantar Hamburg (HAMSOM). Keputusan bagi monsun barat daya dan timur laut dibincangkan. Keputusan simulasi bagi bulan Februari dan Ogos 2007 adalah hampir sama. Hasil simulasi arus permukaan di Selat Melaka adalah berpadanan dengan corak arus yang dilaporkan sebelum ini. Magnitud arus adalah antara 10-70 cm/s ke arah barat laut. Pada lapisan 30 hingga 50 m, magnitud arus adalah 10-30 cm/s ke arah barat laut. Pada bahagian dasar, kelajuan arus ialah 0-20 cm/s ke arah barat laut. Arus pada bahagian permukaan dan lapisan adalah 30-50 cm/s, secara umumnya adalah lebih tinggi pada bulan Februari berbanding pada bulan Ogos. Bagi lapisan bawah pula, magnitud arus antara bulan Februari dan Ogos adalah hampir sama.

Kata kunci: Arus baroclinic; monsun barat daya; monsun timur laut; Selat Melaka

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*Corresponding author, email: syamsul.rizal@unsyiah.net