充放电振子视角下中全新世ENSO振幅减弱的机制研究

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关键词中全新世;ENSO振幅减弱;充放电振子;ENSO 本征模态;温跃层反馈;纬向平流反馈中图分类号：P732.6文献标志码：A 文章编号：2096-3599（2025）06-0071-16DOI：10.19513/j.cnki.hyqxxb.20250102001

Investigating the ENSO amplitude reduction during the mid-Holocene in the perspective of ENSO recharge-discharge oscillator

ZHANG Keying'，SUN Jingwen， XIE Ruihuang（1.College of OceanicandAtmospheric Sciences，Ocean UniversityofChina，Qingdao 26610o，China；2.Laboratoryfor Ocean Dynamics and Climate，Qingdao Marine Science and Technology Center，Qingdao ，China）

AbstractUsing the air-sea coupled model simulations from CMIP6 and PMIP4，this study extracts the intrinsic modes of mid-Holocene ENSO （El Nino-Southern Oscillation） in the perspective of the ENSO recharge-discharge oscillator via the linear inversemodel method，thereby elucidating the dynamic mechanisms for the ENSO amplitude reduction during this period.The research reveals that the reduced ENSO amplitude in the mid-Holocene results from a decreased growth rate of the intrinsic ENSO mode， which is linked to weakened thermocline feedback and zonal advection feedback.The resultsare as follws.（1） The weakened thermocline feedback is primarily driven by a significant reduction in the response strength of the zonal slope of the thermocline to the wind stress over the equatorial central Pacific during autumn and winter of the mid-Holocene.（2） Simultaneously，the weakened zonal advection feedback is attributed to a notable decline in the response strength of anomalous zonal currents in the equatorial eastern Pacific to the wind stress over the equatorial central Pacific during summer-winter. The weakening of these two critical positive feedbacks reduces the development rate of the initial ENSO sea surface temperature anomalies emerged in summer，ultimatelyreducing the ENSO amplitude in winter. （3）In contrast，the enhanced ENSO amplitude in some models is associated with the significantly strengthened thermocline feedback，although the zonal advective feedback is weakened as well but to a smaller extent，compared to the enhancement of thermocline feedback.

Keywordsmid-Holocene；ENSO amplitude reduction；recharge-discharge oscilator；intrinsic ENSO mode；thermocline feedback；zonal advective feedback

0 引言

厄尔尼诺-南方涛动（ElNino-SouthernOscillation，ENSO）是热带太平洋海洋-大气耦合系统中最显著的年际变化信号[1]，对我国天气有重要影响[2]。（剩余20410字）