THREE MODES OF CLIMATE VARIABILITY OF TROPICAL PACIFIC AND ITS RELATION TO ENSO STRENGTH VARIATION
THREE MODES OF CLIMATE VARIABILITY OF TROPICAL PACIFIC AND ITS RELATION TO ENSO STRENGTH VARIATION
复制标题
DOI：
--
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Zhao Yong-pin
中科院分区：
文献类型：
--
作者：
Zhao Yong-pin
利用Kaplan等人重建的1856~2001年全球海温资料，利用Morlet小波变换分析了热带太平洋海温的气候变率。结果表明，热带太平洋海温异常是由年际和年代际气候状态变化及其线性趋势构成的。然后分别对基于2-8、8-30和30-100年带通滤光片的SSTA进行了EOF分析。结果表明，年际分量和年代际分量的首场EOFs都是典型的ENSO型。第一个EOF模的时间序列大约有两个显著的周期，即5年和15年左右的周期，分别对应于年际变化和年代际变化，这意味着当它们同相时，容易发生强ENSO事件；当它们不同相时，强ENSO事件的发生减少；在峰值条件下，这两个周期中的任何一个都可以单独诱发ENSO事件。热带太平洋SSTA气候态变化的第一模在热带西太平洋和赤道东太平洋两侧有明显的异常，它与全球气候跃变和厄尔尼诺事件的发生有密切关系。因此，必须考虑热带太平洋海温异常年代际变化和周期马季奇状态变化对ENSO循环的影响，并将其纳入ENSO模式中，这是提高ENSO预报水平的最佳途径之一。
Based on the global SSTA data from 1856 to 2001 reconstructed by Kaplan et al, the climate variability of the tropical Pacific SSTA was analyzed by the Morlet wave- let transform. The results indicated that SSTA in the tropical Pacific are constituted by interannual and interdecadal climatic state variability, as well as the linear trend. SSTA based on 2--8, 8 -- 30 and 30 -- 100 year band filter was then analyzed by EOF respec- tively. It was found that the first EOFs of both interannual and interdecadal components are typical ENSO pattern. The time series of the first EOF mode approximately have two significant periods, i. e. about 5-year and 15-year periods, corresponding to the in- terannual and interdecadal variabilities respectively, which means, when they are in phase, strong ENSO events tend to occur; when they are out of phase, the occurrence of strong ENSO events is lessened; and either of them at peak condition can also induce an ENSO event alone. The first mode of the climatic state change of the tropical Pacific SSTA has obvious anomalies over the western tropical Pacific and the both sides of equa- torial eastern Pacific, and it has close relations to the global climate jumps and the pat- tern of El Nino events. Therefore, the influence of the interdecadal variability and cli- matic state change of the tropical Pacific SSTA on the ENSO cycle must be considered and should be included in the ENSO models, which is one of the best ways to improve ENSO prediction level.