The diel vertical migration of sound scatterers observed by an acoustic Doppler current profiler in the Luzon Strait from July 2009 to April 2011  

作　　者：YANG Chenghao LIAO Guanghong YUAN Yaochu CHEN Hong ZHU Xiaohua 

机构地区：[1]State Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,State Oceanic Administration

出　　处：《Acta Oceanologica Sinica》2013年第11期1-9,共9页海洋学报（英文版）

基　　金：The National Basic Research Program of China under contract Nos 2007CB816003,2011CB403503 and 2012CB955601;the National Natural Science Foundation of China under contract Nos 41176020 and 41176021;the Scientific Research Fund of the Second Institute of Oceanography,State Oeanic Administration,under contract Nos JT1006 and JG1009

摘　　要：Acoustic Doppler current profiler （ADCP） receives echoes from sound scatterers, then their speed is calcu- lated by the Doppler effect. In the open ocean, most of these backscatterers are from the plankton. The sound scatterers descend down to depth at around dawn, their mean speed is 2.9 cm/s, then they ascend up to the surface layer at around dusk with a mean speed of 2.1 cm/s, in the Luzon Strait. The descending speed is faster, which suggests that this zooplankton population may accelerate its downward migration under the action of the gravity. The vertical distribution of a mean volume backscattering strength （MVB- S） in the nighttime has two peaks, which locate near the upper and lower boundary layers of halocline, respectively. However, the backscatterers only aggregate near the surface layer in the daytime. The diel ver- tical migration （DVM） of sound scatterers has several characteristic patterns, it is stronger in summer, but weaker in winter, and the maximum peak occurs in September. The DVM occurrence is synchronous with the seawater temperature increasing at around dawn and dusk, it may affect the ocean mixing and water stratification,Acoustic Doppler current profiler （ADCP） receives echoes from sound scatterers, then their speed is calcu- lated by the Doppler effect. In the open ocean, most of these backscatterers are from the plankton. The sound scatterers descend down to depth at around dawn, their mean speed is 2.9 cm/s, then they ascend up to the surface layer at around dusk with a mean speed of 2.1 cm/s, in the Luzon Strait. The descending speed is faster, which suggests that this zooplankton population may accelerate its downward migration under the action of the gravity. The vertical distribution of a mean volume backscattering strength （MVB- S） in the nighttime has two peaks, which locate near the upper and lower boundary layers of halocline, respectively. However, the backscatterers only aggregate near the surface layer in the daytime. The diel ver- tical migration （DVM） of sound scatterers has several characteristic patterns, it is stronger in summer, but weaker in winter, and the maximum peak occurs in September. The DVM occurrence is synchronous with the seawater temperature increasing at around dawn and dusk, it may affect the ocean mixing and water stratification,

关 键 词：diel vertical migration acoustic Doppler current profiler mean volume backscattering strength Luzon Strait water stratification 

分 类 号：P716.41[天文地球—海洋科学]