本文選題：全國夏季降水　切入點(diǎn)：長江中下游　出處：《中國氣象科學(xué)研究院》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：本文利用1979-2013年中國氣象局提供的824站點(diǎn)逐日降水觀測資料和NCEP/NCAR再分析資料,分析了全國夏季(5-10月)降水季節(jié)內(nèi)振蕩最顯著周期的分布特征,著重探討了長江中游和長江下游的夏季降水所具有的不同季節(jié)內(nèi)振蕩周期,以及與季節(jié)內(nèi)降水相聯(lián)系的環(huán)流場差異。通過對全國824個臺站的35年夏季降水進(jìn)行季節(jié)內(nèi)尺度的診斷分析,發(fā)現(xiàn)全國夏季降水在季節(jié)內(nèi)振蕩的周期分布上存在一定的規(guī)律。季節(jié)內(nèi)振蕩最強(qiáng)的區(qū)域位于長江以南地區(qū)。使用10-90天Lanczos帶通濾波提取降水的季節(jié)內(nèi)振蕩分量,并使用功率譜分析得到降水季節(jié)內(nèi)振蕩的最顯著周期,發(fā)現(xiàn)全國大部分地區(qū)的季節(jié)內(nèi)振蕩周期集中在30天以內(nèi),長江中游地區(qū)的振蕩周期為10-30天,長江下游振蕩周期為30-60天,華南地區(qū)的振蕩周期為20-30天。對長江流域的中游和下游夏季降水具有不同的顯著振蕩周期這一分布特征,進(jìn)行了分析和診斷。利用位相合成等方法來揭示這兩個區(qū)域在不同周期的季節(jié)內(nèi)振蕩降水、高低空風(fēng)場和高度場以及垂直結(jié)構(gòu)和水汽等循環(huán)過程的演變特征。在200 hPa環(huán)流場上,長江中游的季節(jié)內(nèi)尺度降水主要受到高緯度自西向東傳播的波列影響,而長江下游的季節(jié)內(nèi)尺度降水與鄂霍次克海的高度場的變化存在密切關(guān)系。在風(fēng)場的垂直渦度和散度的位相結(jié)構(gòu)演變過程中,10-30天的垂直渦度和散度有自北向南的移動,而30-60天的垂直渦度和散度在長江以南地區(qū)有自南向北的傳播。水汽輸送的位相發(fā)展過程表明,長江中游的水汽分別來自于南海的向北輸送和長江以北地區(qū)向南的水汽輸送;而長江下游地區(qū)的水汽則主要來自于熱帶東印度洋經(jīng)孟加拉灣的向東輸送并在南海的北向輸送,以及西太平洋水汽向西經(jīng)南海再向長江下游的輸送。另外從高層大尺度環(huán)流場和整層積分的水汽通量輸送上解釋了長江中游10-30天季節(jié)內(nèi)尺度降水的自北向南移動,和長江下游30-60天季節(jié)內(nèi)尺度降水自南向北傳播的原因。
[Abstract]:Based on the daily precipitation observation data and NCEP/NCAR reanalysis data from 824 stations provided by China Meteorological Administration from 1979 to 2013, this paper analyzes the distribution characteristics of the most significant periods of precipitation intraseasonal oscillation in summer in China. The different intraseasonal oscillation periods of summer precipitation in the middle reaches of the Yangtze River and the lower reaches of the Yangtze River are emphatically discussed. And the difference of circulation field associated with seasonal precipitation. Through the diagnostic analysis of 35 years summer precipitation in 824 stations in China, It is found that there is a certain regularity in the periodic distribution of the intraseasonal oscillation of summer precipitation in China. The region with the strongest seasonal oscillation is located in the area south of the Yangtze River. The intraseasonal oscillation component of the precipitation is extracted by 10-90 days Lanczos bandpass filter. Using power spectrum analysis, the most significant periods of intraseasonal oscillation of precipitation are obtained. It is found that the period of intraseasonal oscillation is concentrated within 30 days in most areas of China, the period of oscillation is 10-30 days in the middle reaches of the Yangtze River, and the oscillation period of the lower reaches of the Yangtze River is 30-60 days. The oscillation period in South China is 20-30 days. The phase synthesis method is used to reveal the evolution characteristics of seasonal oscillating precipitation, high and low air wind field, height field, vertical structure and water vapor in the two regions. The seasonal internal scale precipitation in the middle reaches of the Yangtze River is mainly affected by wave trains propagating from west to east in high latitudes. The seasonal internal scale precipitation in the lower reaches of the Yangtze River is closely related to the variation of the height field in the Okhotsk Sea. During the evolution of the vertical vorticity and divergence of the wind field, the vertical vorticity and divergence of the wind field move from north to south in 10-30 days. The vertical vorticity and divergence of 30-60 days propagate from south to north in the south of the Yangtze River. The phase development process of water vapor transport indicates that the water vapor in the middle reaches of the Yangtze River comes from the northward transport of the South China Sea and the water vapor transport from the north of the Yangtze River to the south. The water vapor in the lower reaches of the Yangtze River is mainly transported eastward from the tropical eastern Indian Ocean through the Bay of Bengal and northward in the South China Sea. And the transport of water vapor from the western Pacific to the South China Sea and then to the lower reaches of the Yangtze River. In addition, from the large-scale circulation field at the upper level and the integrated water vapor flux transport in the whole layer, it is explained that the internal scale precipitation in the middle reaches of the Yangtze River moves from north to south during the 10-30 days of the season. And the causes of the internal scale precipitation propagating from south to north in 30-60 days in the lower reaches of the Yangtze River.
【學(xué)位授予單位】：中國氣象科學(xué)研究院
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：P426.6

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 齊艷軍;張人禾;Tim LI;;1998年夏季長江流域大氣季節(jié)內(nèi)振蕩的結(jié)構(gòu)演變及其對降水的影響[J];大氣科學(xué);2016年03期

2 胡婭敏;翟盤茂;羅曉玲;呂俊梅;覃志年;郝全成;;2013年華南前汛期持續(xù)性強(qiáng)降水的大尺度環(huán)流與低頻信號特征[J];氣象學(xué)報(bào);2014年03期

3 李麗平;許冠宇;柳艷菊;;2010年華南前汛期低頻水汽輸送對低頻降水的影響[J];熱帶氣象學(xué)報(bào);2014年03期

4 齊艷軍;容新堯;;次季節(jié)-季節(jié)預(yù)測的應(yīng)用前景與展望——“次季節(jié)-季節(jié)預(yù)測(S2S)”會議評述[J];氣象科技進(jìn)展;2014年03期

5 洪偉;任雪娟;;Persistent Heavy Rainfall over South China During May August:Subseasonal Anomalies of Circulation and Sea Surface Temperature[J];Acta Meteorologica Sinica;2013年06期

6 王文;李偉;李耀輝;;黃河中下游地區(qū)夏季旱澇年低頻振蕩特征分析[J];冰川凍土;2013年04期

7 楊雙艷;武炳義;張人禾;周順武;;夏季歐亞中高緯大氣低頻振蕩的緯向傳播特征[J];中國科學(xué):地球科學(xué);2013年07期

8 孫國武;李震坤;信飛;何金海;;用低頻天氣圖方法進(jìn)行延伸期預(yù)報(bào)的探索[J];氣象科技進(jìn)展;2013年01期

9 劉慧斌;溫敏;何金海;張人禾;;東北冷渦活動的季節(jié)內(nèi)振蕩特征及其影響[J];大氣科學(xué);2012年05期

10 楊秋明;宋娟;李熠;謝志清;黃世成;錢瑋;;全球大氣季節(jié)內(nèi)振蕩對長江流域持續(xù)暴雨影響的研究進(jìn)展[J];地球科學(xué)進(jìn)展;2012年08期

相關(guān)碩士學(xué)位論文 前1條

1 苗芮;華南前汛期持續(xù)性降水異常與準(zhǔn)雙周振蕩[D];中國氣象科學(xué)研究院;2016年

，

本文編號：1616130