Study on the Spectral Properties of Typhoon Generated Waves in Deep Sea

• Main Authors: Lai, Ru-Yu, 賴如鈺
• Other Authors: Tsai, Cheng-Han
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/03916149553072440848

碩士 === 國立臺灣海洋大學 === 海洋環境資訊系 === 103 === The purpose of this study is to understand the spectral properties of typhoon generated waves observed in the deep sea buoy. There were 4721 spectra recorded by Taitung Deep Sea Buoy from 18 typhoons in recent years. The results show: The typhoon waves have more narrow spectra than in the ordinary seas. Swells with both unimodal and bimodal spectra are found. The average peak period of the unimodal-spectrum swell is larger than 13.4s and has already larger wave heights. Unimodal-spectrum swells occur always when typhoon is still far from the buoy, however when typhoon moves into 2 to 4 times of R7 (radius of Beaufort wind scale 7) the bimodal-spectrum swells occur. This study found the slope of equilibrium range in the high frequency of spectra is proportional to the power of -4.77. The result shows JONSWAP fits the unimodal spectra of typhoon wave very well. The average enhancement factor in JONSWAP is 1.125 which means the waves are close to be fully developed.