Wave Characteristics in Natuna Waters during Typhoon Hagibis Event

Abstract

Significant Wave Height (SWH) in Natuna Waters (NW) has been simulated during Typhoon Hagibis (TH) event in the periods of 20th – 27th November 2007 in South China Sea (SCS) by using Simulating WAve Nearshore (SWAN) model with 1/24° spatial resolution. The 1/4° wind data obtained from Cross-Calibrated Multi-Platform (CCMP) and 1/120° bathymetry data derived from General Bathymetry Chart of the Ocean (GEBCO) were used as model input. The open boundary values for SWAN simulation were obtained from WAVEWATCH-III (WW3) results provided by Indonesian Geospatial Information Agency (BIG). In this current study, it was found that the TH had an impact on swell propagation from the SCS to the NW. The model results showed that SWH in the NW during peak phase of the TH (22nd 23rd November 2007) varied between 0.8 – 3.5 m. There were 6 observation points in the study area to investigate SWH variation from 22nd October – 22nd December 2007. Based on the results, the northern part of the Natuna, Subi Besar and Anambas Islands are showed in Point 1 (P1), Point 3 (P3) and Point 5 (P5), respectively. Meanwhile, the southern part of the Natuna, Subi Besar, and Anambas Islands are showed in Point 2 (P2), Point 4 (P4) and Point 6 (P6). TH in the peak phase generates the SWH at P1, P3, and P5 of about 0.6 – 2.5 m and generates the SWH at P2, P4, and P6 of about 0. 5 – 1.6 m.