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通过TIMS-U系测年和纹层计数年代学研究,建立了18～14kaBP南京汤山洞穴石笋纹层生长时间序列,其中18179~14900 aBP时段年纹层生长速率提供了末次盛冰期东亚夏季风锋区年际降水变率信息.经功率谱分析,发现该时段存在显著的2~7年周期,与现今季风降水记录中厄尔尼诺-南方涛动(ENSO)周期相吻合,进一步证实ENSO事件可以出现于盛冰期极端寒冷的气候边界条件.石笋年生长速率的分段功率谱分析表明,ENSO周期的低频信号(4~7年)在18179～14900 aBP时段呈逐渐减弱的趋势,支持ENSO事件的岁差旋回日辐射驱动模型.然而,Hl事件时ENSO周期信号的重现,可能说明东亚冬季风的显著增强对El Nino事件具有激发作用.
The time series of stalagmite growth in Nanjing Tangshan caves were established from the dating of TIMS-U series and the chronogeometric study. The growth rates of annual stratum from 18179 to 14900 aBP provided the last glacial ebb summer monsoon The results of power spectrum analysis show that there are significant periods of 2 ~ 7 years in this period, consistent with the El Niño-Southern Oscillation (ENSO) cycle in the present monsoon precipitation record, which further confirms that ENSO events can occur in The frost-climatic climatic boundary conditions during the climatic ice period show that the low-frequency ENSO signal (4-7 years) tends to weaken from 18179 to 14900 aBP, and support the ENSO event precession cycle Day radiation-driven model.However, the recurrence of the ENSO period signal at the time of the Hl event may indicate that the significant enhancement of the East Asian winter monsoon has an incentive to the El Nino event.