南海中部上层海洋温度的短周期振动

THE SHORT-TERM OSCILLATION OF TEMPERATURE IN UPPER LAYER IN CENTRAL SOUTH CHINA SEA

南海季风试验（sCSMEx）期间，南海中部投放了3个ATLAS浮标。本文选取3个站点1998年4月13日～1999年4月8日的所有观测水层的温度数据作为研究。通过逐月功率谱分析，发现50--500m深度，温度存在全日和半日2个显著短周期的振动；利用小波分析得出了温度短周期振动的时空变化特点，并结合温度跃层时空结构的分析，发现跃层深度上，温度全日（或半日）周期振动的时空变化与跃层时空结构存在一致性，即在跃层核心深度上，跃层强度越大的时域内，温度全日（或半日）周期的振动就越显著。

During the South China Sea Monsoon Experiment （SCSMEX）, three ATLAS anchored buoys were deployed in the central South China Sea. The temperature data of all observed layers from April 13, 1998 to April 8, 1999 were used. The monthly power spectrum analysis shows that in the depth of 50m to 500m, there are two remarkable short-term period oscillations in temperature, which are diurnal and semi-diurnal period respectively. Using wavelet analysis the characteristic of spatial and time variability of short-term oscillation in temperature was got. Combining the analysis of spacial and time structure of thermocline, the conclusion can be drawn that on the depth of thermocline, the spatial and time variation of diurnal （semi-diurnal） period in temperature is in agreement with the special and time structure of thermocline, that is, in the central depth of thermocline, the diurnal （semi-diurnal） period oscillation in temperature is more obvious in the time zone where the intensity of thermocline is larger.