Internal solitary waves on the southwest shelf of Dongsha Island observed from mooring ADCP  

作　　者：蔺飞龙 侯一筠 刘亚豪 方泳 胡珀 

机构地区：[1]Institute of Oceanology, Chinese Academy of Sciences [2]Key Laboratory of Ocean Circulation and Waves ( KLOCAW ), Chinese Academy of Sciences [3]University of Chinese Academy of Sciences

出　　处：《Chinese Journal of Oceanology and Limnology》2014年第5期1179-1187,共9页中国海洋湖沼学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(Nos.41030855,U1133001,41376027);National High Technology Research and Development Program of China(863 Program)(No.2013AA09A502)

摘　　要：Internal solitary waves （ISWs） are frequently observed in the area between Dongsha Island （DI） and Taiwan Island. However, there have been few in-situ observations southwest of DI. To improve our knowledge of ISWs in this area, we observed the ISWs over the continental shelf （115.4°E, 20.3°N） from Aug. 29 to Oct. 10, 2011 with temperature sensors and an acoustic Doppler current profiler （ADCP）. The observations showed that the a fully developed ISW produced a current whose maximum westward velocity was 0.92 rrds and maximum northward velocity was 0.47 m/s. During the 41-day observation period the ISWs appeared for three periods with about 7-day gaps between each period. During each day, two types of ISWs were observed. The first type of wave arrived regularly diurnally at the same time each day, with a similar pattern to that of the type-a wave identified by Ramp et al. （2004）. The second type arrived about 12 h after the first type and was delayed about 1 hour each day; this wave type was related to the type-b wave. Thus, our observations confirmed that both type-a and type-b waves can reach the area southwest of the DI. Moreover, the waves observed by the mooring propagated toward the directions of 270°-315° clockwise from true north, indicating obvious refraction from uneven topography around DI.Internal solitary waves(ISWs) are frequently observed in the area between Dongsha Island(DI) and Taiwan Island. However, there have been few in-situ observations southwest of DI. To improve our knowledge of ISWs in this area, we observed the ISWs over the continental shelf(115.4°E, 20.3°N) from Aug. 29 to Oct. 10, 2011 with temperature sensors and an acoustic Doppler current profiler(ADCP). The observations showed that the a fully developed ISW produced a current whose maximum westward velocity was 0.92 m/s and maximum northward velocity was 0.47 m/s. During the 41-day observation period the ISWs appeared for three periods with about 7-day gaps between each period. During each day, two types of ISWs were observed. The first type of wave arrived regularly diurnally at the same time each day, with a similar pattern to that of the type- a wave identified by Ramp et al.(2004). The second type arrived about 12 h after the first type and was delayed about 1 hour each day; this wave type was related to the type- b wave. Thus, our observations confirmed that both type- a and type- b waves can reach the area southwest of the DI. Moreover, the waves observed by the mooring propagated toward the directions of 270°–315° clockwise from true north, indicating obvious refraction from uneven topography around DI.

关 键 词：internal solitary wave （ISWs） South China Sea Dongsha Island REFRACTION 

分 类 号：P714.1[天文地球—海洋科学]