Abstract
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.
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Supported by the National Natural Science Foundation of China (Nos. 41030855, U1133001, 41376027) and National High Technology Research and Development Program of China (863 Program) (No. 2013AA09A502)
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Lin, F., Hou, Y., Liu, Y. et al. Internal solitary waves on the southwest shelf of Dongsha Island observed from mooring ADCP. Chin. J. Ocean. Limnol. 32, 1179–1187 (2014). https://doi.org/10.1007/s00343-014-3254-8
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DOI: https://doi.org/10.1007/s00343-014-3254-8