Understanding the Mechanism of Currents through the Malacca Strait Study Case 2020 – 2022 : Mean state, Seasonal and Monthly Variation

Abstract

The Malacca Strait is the importance waters for international shipping routes and more 200 cases of ship collisions in the period 1970-2015 in this strait. That is related to some a shallow depth waters with many small islands and strong current which is making this strait have a highest risk in certain seasons. The CMEMS data used to understanding of mechanism of current, illustrate the pattern and tranport volume. The research uses descriptive and the statistical methods to understanding of mechanism and variability of current. The analysis of current patterns and water level shows that during the monsoon winds active, the current always moves to the Andaman Sea, we called the southeast current system. The Northeast (NE) and Southwest (SW) monsoon wind is strongly influence to the mechanism of formation southeast current system, which causes the varition in sea level hight in eastern and western of Malacca Strait. During the NE monsoon season, the water masses of the South China Sea are push away into the Karimata Strait, causing the sea level in the eastern part to be higher than the western part and will increase the current speed. On the other hand, during the SW monsoon season, the water masses from the Karimata Strait is pushed away from the eastern part of the Malacca Strait which causes the sea level decrease and causes the current speed to weaken. Numbers eddies phenomenon were found at the Malacca Strait each season. The anticyclonic eddies occurred almost every season centered at 3° - 5° N, 97° - 100° E. Meanwhile anticyclonic eddies appear around the northern part of Sumatra centered at 4° - 5°N, 99° - 101°E during SW Monsoon season and the eddies formation also existed during the second transition monsoon season.

Ketidakseragaman Sebaran Spasial Variabilitas Musiman Eddy di Perairan Barat Laut Indonesia

“…Nilai EKE menunjukkan nilai yang sangat tinggi di antara 2°N -6°N. Besarnya nilai EKE, tetapi kecilnya frekuensi sirkulasi arus eddy yang terdeteksi pada daerah Selat Malaka menunjukkan bahwa nilai EKE tersebut didapat dari arus lokal yang kuat terdapat pada celah sempit di daerah Selat Malaka (Haditiar et al, 2020;Wibowo et al, 2022). Daerah yang terdapat banyak sirkulasi arus eddy pada bagian utara daerah penelitian (5°N -10°N) memiliki rentang nilai EKE yang lebih kecil, yaitu mendekati 0 hingga 600 cm 2 s -2 yang ditunjukkan dengan wilayah berwarna biru pada Gambar 4b.…”