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氣候變化研究進(jìn)展 ?? 2011, Vol. 7 ?? Issue (4): 243-247.
楊秋明1,錢(qián)瑋1,2,李熠1,2,黃世成1,2,謝志清1,2
摘要: 利用集合經(jīng)驗模態(tài)分解(EEMD)方法研究了登陸中國熱帶風(fēng)暴頻數的非平穩年際和年代際變化主要周期型。對1951—2006年登陸中國的熱帶風(fēng)暴頻數序列進(jìn)行分解,分別得到包含有準4年(C01)、6~7年(C02)的年際周期分量和14~16年(C03)的年代際周期分量的時(shí)間變化型。這些分量給出了登陸中國熱帶風(fēng)暴頻數在不同時(shí)間尺度上獨立的變化特征,其中C01周期分量強度最大,且與ENSO有關(guān)。登陸中國的熱帶風(fēng)暴頻數趨勢分量不顯著(zhù),表明近56年來(lái)登陸中國熱帶風(fēng)暴無(wú)明顯增加(減少)趨勢。這些周期分量與夏季海平面氣壓場(chǎng)的相關(guān)分析表明,登陸中國熱帶風(fēng)暴頻數年代際變化與南半球熱帶和中高緯度環(huán)流系統的相互作用密切相關(guān)。
關(guān)鍵詞: 登陸熱帶風(fēng)暴, 中國, 集合經(jīng)驗模態(tài)分解(EEMD), 海平面氣壓場(chǎng), landfall tropical storm, China, nsemble empirical mode decomposition (EEMD), sea level pressure
Abstract: Ensemble empirical mode decomposition (EEMD) method was adopted to study the non-stationary interannual and decadal variations of landfall tropical storm number in China. Time series of the landfall tropical storm number of 56 years (1951-2006) can be decomposed into a series of modes, mainly including the quasi 4 years (C01), 6-7 years (C02) and 14-16 years (C03) oscillation components. Among them, the quasi 4-year oscillation with the largest amplitude is related to ENSO. In brief, the EEMD method instead of traditional and conventional decomposition methods can bring us the isolated characteristics of the temporal variations of the landfall tropical storm number on various time scales, especially on the interannual and decadal timescales. In addition, the long-range trend is not obvious, indicating that there was no increasing or declining trend in the series of landfall tropical storm number in the past 56 years. Moreover, the correlation analysis also suggests that the interdecadal variations of landfall tropical storm number in China were closely related to the interaction between tropical and extratropical circulation systems in the Southern Hemisphere.
中圖分類(lèi)號:
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