近赤道海温对西太平洋副高强度的影响机理——模糊映射诊断

针对近赤道海温对西太平洋副高影响的复杂性和不确定性问题,引入自适应模糊推理系统方法,系统地分析了西太平洋副高强度对赤道东太平洋、赤道西太平洋和赤道印度洋等海区海温状况和冷暖变化的响应态势和响应程度。研究表明:副高对赤道东太平洋海温的变冷(增暖)过程将出现正距平的增强(减弱)响应,响应幅度随时间减弱(增强);副高对赤道印度洋海温增暖(变冷)的响应态势与对赤道东太平洋海温的响应态势相反,响应幅度远小于赤道东太平洋海温变化的响应幅度;副高对赤道西太平洋海温的增暖急缓表现出不同的响应态势,迅速增暖利于副高衰减,缓慢增暖则利于副高增强,而对于海温的变冷过程则有滞后的增强响应趋势。此外,上述海区的海温冷暖变化幅度和速度是导致副高变异的主要因素,较之海温基本热力状况对副高强度的影响更为显著。

Influence mechanism of equatorial SST on West Pacific subtropical high intensity:Fuzzy mapping diagnosis

Aiming at such complexity and uncertainty problems as the influence of equatorial sea surface temperature(SST) on West Pacific subtropical high,by introducing the fuzzy mapping idea and ANFIS(Adaptive-Netwook-Based Fuzzy Inference System) technique,the response trend and degree of West Pacific subtropical high intensity to the thermal pattern and shift of SST in equatorial eastern Pacific,western Pacific,and equatorial Indian ocean are analysed and discussed.Results show that the enhancing(weakening) response of subtropical high is corresponding to the SST cooling(warming) in equatorial eastern Pacific,and the response amplitude weakens(enhances) with time.The weakening(enhancing) response of subtropical high is corresponding to the SST cooling(warming) in equatorial Indian ocean,and the response amplitude is far less than that to the SST in equatorial eastern Pacific.The different response trends of subtropical high are corresponding to the different pace warming in equatorial western Pacific,viz.the rapid(slow) warming of SST in western Pacific is suitable for the weakening(enhancing) of subtropical high,and the delayed enhancing response is corresponding to the SST cooling in equatorial western Pacific.Some new viewpoints are introduced as follows:the SST shift range and rate are the key impact factors of subtropical high aberrance,and their influences are more notable than those of basic thermal status of equatorial SST.