Model Sebaran Tumpahan Minyak di Lintas Utara Selat Malaka

Abstract

ABSTRAK NAURAH ALIFAH RAMADHANA. Selat Malaka bagian utara merupakan jalur pelayaran padat dan rentan terhadap risiko tumpahan minyak, namun studi pemodelan trayektori tumpahannya masih terbatas. Penelitian ini bertujuan memodelkan sebaran dan nasib tumpahan minyak hipotetik di lintas utara Selat Malaka menggunakan General NOAA Operational Modeling Environment (GNOME), dengan data arus dan pasang surut dari Copernicus Marine Service (CMEMS) serta data angin dari ERA5 sebagai gaya penggerak, yang divalidasi terhadap data observasi arus, pasut, dan angin primer. Simulasi dilakukan pada dua jenis minyak, Arabian Light dan Swallow Ace, mewakili musim utara dan musim selatan pada empat kondisi fase pasut. Hasil validasi menunjukkan keandalan tinggi pada data arus dan pasut, sedangkan data angin memiliki keterbatasan akibat resolusi data observasi. Pola arus dan angin musiman memengaruhi luas dan arah sebaran tumpahan, dengan musim selatan menghasilkan sebaran lebih luas namun musim utara menghasilkan fraksi terdampar lebih tinggi. Nasib minyak Arabian Light didominasi oleh evaporasi, sedangkan Swallow Ace didominasi oleh fraksi terapung akibat sifat persisten dan viskositas tinggi. Analisis tumpang susun terhadap ekosistem pesisir menunjukkan risiko lebih tinggi terhadap terumbu karang dibandingkan hutan mangrove, dengan risiko meningkat pada musim selatan.

ABSTRACT NAURAH ALIFAH RAMADHANA. The northern Strait of Malacca is a heavily trafficked shipping lane vulnerable to oil spill risk, yet trajectory modeling studies for this region remain limited. This study aims to model the dispersion and fate of a hypothetical oil spill in the northern Strait of Malacca using the General NOAA Operational Modeling Environment (GNOME), by current and tidal data from the Copernicus Marine Service (CMEMS) and wind data from ERA5, validated against primary current, tidal, and wind observations. Simulations were conducted for two oil types, Arabian Light and Swallow Ace, representing the northeast and southwest monsoon seasons under four tidal phase conditions. Validation results showed high reliability for current and tidal data, while wind data showed limitations due to the resolution of observational data. Seasonal current and wind patterns influenced the extent and direction of the spill, with the southwest monsoon producing wider dispersion while the northeast monsoon produced a higher stranded fraction. Arabian Light's fate was dominated by evaporation, whereas Swallow Ace was dominated by the floating fraction due to its persistent and highly viscous nature. Overlay analysis with coastal ecosystems indicated higher risk to coral reefs than to mangrove forests, with risk increasing during the southwest monsoon.