我国东南海域云出现概率和海表温度的关系分析

ANALYSIS OF THE CONNECTION BETWEEN FREQUENCY OF OCCURRENCE OF CLOUDS AND SST IN SOUTHEAST AND SOUTH CHINA SEAS

海表温度(SST)和云是表征海洋和大气状况的主要物理量。为了掌握我国东南海域两者间的某些特征,综合使用CloudSat卫星观测和SODA3.3.1中的SST资料,分别就垂直方向上的云出现概率(FOC)和SST的变化关系进行了基本的统计分析。结果表明,尽管两海域FOC随高度分布均是SST相对低时,低层大高层小;随着SST增暖逐渐是高层大于低层的。但分布强度及其与SST的变化范围划分有所不同。相比而言,南海海域低层FOC高度相对低,变化幅度也相对大。特别是在SST>30.5℃时,台湾以东海域FOC是减弱的,而南海的则是维持或增强。研究结果不仅有助于直观掌握两海域FOC和SST间的变化关系,而且定量化揭示局地海气相互作用中SST与云的对应关系。

Sea surface temperature(SST)and cloud are the main physical features of ocean and atmosphere respectively.To probe into some vertical features between the frequency of occurrence of clouds(FOC)and SST off the southeastern China,CloudSat satellite data for cloud and the SODA 3.3.1 for SST are used to analyze statistically in this paper.The results show that the distribution of FOC with height is similar for the sea east of Taiwan and South China Sea in that with relatively low SST,it is larger in the low level than in the high level,but the intensity of its distribution as well as its variation with SST is different.Compared with the sea east of Taiwan,the height of FOC variation in the South China Sea is lower and its amplitude is also larger.Especially when SST is above 30.5℃,the FOC decreases with increasing SST in the sea east of Taiwan.By contrast,the FOC remains strong or even enhances in the South China Sea.These results are not only useful for understanding the connection between FOC and SST in the two areas,but also quantitatively reveal their corresponding relationship in the local air-sea interaction.