基于一个海洋混合层模式对中国近海浮标SST日变化的模拟

Simulation of diurnal variation of sea surface temperature in China offshore area using an ocean mixed layer turbulent energy forecast model

收集整理了中国近海18个浮标2011年全年的高时频实时观测资料,对中国近海SST日变化时空分布规律进行了分析,并利用一个改进了的一维海洋混合层模式对中国近海浮标资料进行了模拟。分析表明,中国近海SST日变化具有明显的季节变化特征。按照各季节SST日变化的明显程度,可以把近海海域分为两季型与四季型。两季型海域的SST日变化在春夏季非常明显,且变化幅度一致,而秋冬季日变化明显减小,如渤海、黄海北部和东海北部。而东海南部和南海北部等四季型海域的SST日变化幅度在各个季节均不相同,具有四季分明的特征。各个海域的短波辐射等热力通量、海面风应力等动量通量,以及上层海流等因素是造成上述分布特征的主要原因。文中使用的海洋混合层模式在对不同浮标观测SST的逐日演变过程中表现良好,对平均日变化的模拟比较合理,可以模拟出连续的、完整的SST日变化周期,并且与观测基本一致,该模式在中国近海区域具有良好的应用前景。

The spatial and temporal features of diurnal variation of sea surface temperature （DSST） in China off- shore area were analyzed through the high frequency buoy data, and a revised ocean mixed layer turbulent energy forecast model was introduced for cases study. The analysis shows that the DSST around China coastal waters had some significant seasonal variation characteristics, and can be defined as two-season and four-season type according to different DSST. Two-season type has obvious and similar DSST in spring and summer, but unapparent DSST in autumn and winter, such as in the Bohai Sea, the north area of the Yellow Sea and the north area of the East China Sea. Four-season type show different characteristic of DSST in each season, such as the south of the East China Sea and the north area of South China Sea. Different thermodynamic properties in each area cause these characteristics. For the simulation, the revised model has a good performance in modeling the daily evolution of SST, and the result of averaged DSST is also reasonable. The model can reproduce a continuous and integrated SST diurnal variation in proximity to different buoy observations, which means it has a stable performance. These results suggest that this mixed layer model can facilitate a more credible application.