PEMANFAATAN SATELIT ALTIMETRI UNTUK VERIFIKASI TINGGI GELOMBANG SIGNIFIKAN OCEAN FORECAST SYSTEM (OFS) – MODEL BMKG
DOI:
https://doi.org/10.31172/jmg.v19i2.586Keywords:
OFS, Altimetri, SWH, VerifikasiAbstract
Model OFS-BMKG yang sudah beroperasi sejak akhir tahun 2016 belum banyak dilakukan verifikasi secara menyeluruh di perairan Indonesia. Penelitian kali ini melakukan kajian verifikasi tinggi gelombang laut signifikan (SWH) hasil pemodelan OFS menggunakan pengamatan satelit altimetri untuk periode Januari 2017. Verifikasi dilakukan dengan menyesuaikan posisi SWH yang diperoleh dari lintasan satelit terhadap kontur model menggunakan grid yang sama. Hasil analisis statistika menunjukkan nilai koefisien korelasi SWH antara hasil model dengan pengamatan satelit tergolong baik, yaitu sebesar 0.64. Sedangkan untuk uji bias, RMSE, dan SI masing-masing bernilai 0.41, 0.89, dan 0.52. Secara umum bila dilihat dari plot time series dan sebaran data setiap waktu pengamatan umumnya hasil model lebih tinggi dibandingkan pengamatan satelit. Sehingga dibutuhkan penyesuaian untuk hasil model agar sesuai dengan pengamatan sebenarnya.
The OFS-BMKG system has been operating since the end of 2016 but has not been verified in Indonesian waters. This system was developed from the WaveWatch III (WW3) model. This study was conducted to verify OFS Significant Wave Height (SWH) against satellite altimetry measurements for the period of January 2017. The verification was performed by adjusting the position of SWH obtained from the altimetry satellite path to the contour of the WW3 model for the same grids. The results showed that the OFS SWH had good accordance with the satellite measurement. The correlation coefficient was 0,64 while bias, RMSE, and SI values were 0,41; 0,89; and 0,52, respectively. The time series and data distribution showed that OFS SWH, in general, had higher values than that measured by altimetry satellite. Adjustments or fine-tuning therefore are required for the WW3 model results to match actual observations.
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