Deteksi Sebaran Tumpahan Minyak Berdasarkan Data Satelit di Perairan Karawang, Jawa Barat

Abstract

Tumpahan minyak akibat kebocoran minyak di sekitar anjungan lepas pantai di perairan Karawang telah menimbulkan dampak negatif bagi sumberdaya alam, lingkungan, dan ekonomi. Penelitian ini bertujuan mendeteksi sebaran tumpahan minyak di perairan Karawang, Laut Jawa mengunakan citra satelit optik (Aqua-MODIS, Landsat 8, dan Sentinel 2B) berdasarkan perbedaan nilai spektral remote sensing reflectance (Rrs) kanal RGB dan penerapan algoritma (oil spill index, fluorescence index, dan NDVI). Nilai spektral Rrs di daerah yang terdapat tumpahan minyak lebih tinggi dibandingkan dengan lokasi yang tidak terkena tumpahan minyak karena lapisan minyak memiliki indeks bias yang tinggi sehingga merefleksikan radiasi lebih besar dibandingkan permukaan air laut bersih. Secara umum, algoritma NDVI menghasilkan peta sebaran tumpahan minyak yang terbaik. Berdasarkan visualisasi true color pada satelit Aqua-MODIS tanggal 13 Juli 2019 dan 15 Juli 2019, satelit Landsat-8 tanggal 25 Juli 2019, Sentinel 2B tanggal 28 Agustus 2019, estimasi luas sebaran minyak berturut-turut adalah 21,9396 km², 35,0338 km², 23,4737 km², dan 10,5114 km². Minyak menyebar ke arah Barat–Barat Laut pada jangka waktu Juli–Agustus 2019.

Oil spills around an oil offshore platform in the Karawang waters had a negative effect on natural resources, environment, and economic. The main purposes of this research were to detect oil spills in Karawang waters, Java Sea by using an optical satellite images (Aqua-MODIS, Landsat 8, and Sentinel 2) based on differences in remote sensing reflectance (Rrs) value in RGB bands and the application of several algorithms (oil spill index, fluorescence index, and NDVI) on images processing. Rrs values were higher where oil spills were detected, because the oil layers had a high refractive index causing the oil surface to reflect radiation greater than clean water surface. In general, the NDVI algorithm produced the best map of the distribution of oil spills. Based on true color visualization on the Aqua-MODIS satellite on 13 July 2019 and 15 July 2019, Landsat-8 satellite on 25 July 2019, Sentinel 2B on 28 August 2019, the estimated oil spreading area were 21.9396 km², 35.0338 km², 23.4737 km², and 10.5114 km², respectively. The oil spills spreaded from East to Westward–Northwest on July–August 2019.