天山地区夏季降水的小时尺度特征
发布时间：2018-09-14 20:07
【摘要】：本文综合利用台站观测数据,详细分析了夏季天山地区小时尺度降水的气候态特征与地形的关系。结果表明,天山地区降水受地形影响显著,降水量、降水频率和降水持续事件随海拔升高而增大;整体降水强度结构以弱降水为主,强降水较少。伊犁河谷地区自西向东降水随地形抬升而增大、弱降水频次增多。天山中段地区降水分布呈两侧低中间高的特征,高海拔处弱降水发生频次最高。天山地区以发生于午后至傍晚的短时降水事件为主,持续时间较短,日变化也受到地形的显著影响。伊犁河谷内降水峰值出现在傍晚至夜间,降水发生时,地面多为西南风和东北风;天山中段地区不同区域降水日位相差别较大,天山上为傍晚峰值,北侧(南侧)为夜间(清晨)峰值,不同区域影响降水的主要风向也存在差异,天山上降水发生时以偏西风和偏北风为主,南北两侧以对应的下坡风风向为主。对天山中段夏季降水的日变化特征进行分析发现,降水频率与对流云出现频次的日变化在天山中段地区均表现出三个典型模态:天山南侧对流和降水峰值出现于清晨,天山上对流和降水峰值出现于下午,天山北侧对流和降水的峰值时间均为夜间。通过定义区域降水事件(RRE)并对RRE的开始站点进行筛选,从每一次降水事件的角度分析降水的日变化特征以及不同区域之间日变化特征的相关关系。结果表明,天山南侧的清晨降水峰值孤立于其余两个区域存在,由南侧局地生消的降水事件产生;天山上降水的下午峰值和天山北侧降水的夜间峰值都主要由始于天山上的降水事件贡献产生,这类降水事件多于下午在天山上开始出现,随后北移造成北侧盆地的夜间降水峰值。利用再分析资料和WRF模拟结果对天山地区环流的日变化特征分析得出,午后于天山上触发的对流以及清晨于天山南侧触发的对流均与天山及其周边地区环流场和热力场的日变化有关。午后,天山上出现较强的低空辐合以及热力学不稳定度,有利于天山上对流的触发,造成天山上的午后峰值。清晨,辐合中心出现在天山南侧盆地,配合南侧大气的热力学不稳定能量,有利于天山南侧对流的触发,造成南侧的清晨降水峰值。
[Abstract]:Based on the observational data, the relationship between climatic characteristics and topography of hourly scale precipitation in Tianshan area in summer is analyzed in detail in this paper. The results show that the precipitation in Tianshan area is significantly affected by topography, the precipitation amount, precipitation frequency and precipitation sustained events increase with the elevation, and the intensity structure of the whole precipitation is mainly weak precipitation, with less strong precipitation. The precipitation from west to east in Yili River Valley increases with the elevation of topography, and the frequency of weak precipitation increases. The precipitation distribution in the middle part of Tianshan Mountain shows the characteristics of low middle height on both sides and the highest frequency of weak precipitation at high altitude. In Tianshan area, the short-time precipitation events mainly occurred from the afternoon to the evening, which lasted for a short time, and the diurnal variation was also significantly affected by the topography. The peak value of precipitation in the Yili River Valley occurred in the evening to the night, when the precipitation occurred, the surface was mostly southwest wind and northeast wind, and the daily phase of precipitation in different regions of the middle part of Tianshan Mountain was different, and the peak value was in the evening on Tianshan Mountain. The north side (south side) is the peak value at night (early morning), and the main wind direction affecting precipitation in different regions is also different. The westerly wind and the northerly wind are dominant when the precipitation occurs on Tianshan Mountain, and the corresponding downhill wind direction is dominant on the north and south sides. Based on the analysis of the diurnal variation characteristics of summer precipitation in the middle segment of Tianshan Mountain, it is found that the diurnal variation of precipitation frequency and convective cloud frequency show three typical modes in the middle segment of Tianshan Mountain: the convection in the south side of Tianshan Mountain and the peak value of precipitation in the early morning. The peak of convection and precipitation occurred in the afternoon, and the peak time of convection and precipitation on the north side of Tianshan Mountain were both nocturnal. By defining the regional precipitation event (RRE) and screening the starting stations of the RRE, the diurnal variation characteristics of precipitation and the correlation between the diurnal variation characteristics of different regions are analyzed from the point of view of each precipitation event. The results show that the peak value of early morning precipitation on the southern side of Tianshan Mountain is isolated from the other two regions, resulting from the local precipitation events in the southern side. The afternoon peak of precipitation on Tianshan Mountain and the nocturnal peak of precipitation on the northern side of Tianshan Mountain are mainly caused by the contribution of precipitation events that started on Tianshan Mountain, and these precipitation events appear more frequently on Tianshan Mountain in the afternoon than on Tianshan Mountain in the afternoon. Then the northward movement resulted in the peak value of nocturnal precipitation in the northern basin. Based on the reanalysis data and WRF simulation results, the diurnal variation characteristics of the circulation in Tianshan region are analyzed. The convection triggered in the afternoon on Tianshan Mountain and in the south of Tianshan Mountain in the early morning is related to the diurnal variation of circulation field and thermal field in Tianshan Mountain and its surrounding area. In the afternoon, strong convergence at low level and the degree of thermodynamics instability appear on Tianshan Mountain, which is favorable to the triggering of convection on Tianshan Mountain, resulting in the afternoon peak value of Tianshan Mountain. The convergence center appeared in the southern Tianshan basin in the early morning, which combined with the thermodynamics instability energy in the southern side of the atmosphere, which was favorable to the triggering of convection on the southern side of Tianshan Mountain, resulting in the peak value of early morning precipitation on the southern side of Tianshan Mountain.
【学位授予单位】：中国气象科学研究院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P426.6
本文编号：2243739
[Abstract]:Based on the observational data, the relationship between climatic characteristics and topography of hourly scale precipitation in Tianshan area in summer is analyzed in detail in this paper. The results show that the precipitation in Tianshan area is significantly affected by topography, the precipitation amount, precipitation frequency and precipitation sustained events increase with the elevation, and the intensity structure of the whole precipitation is mainly weak precipitation, with less strong precipitation. The precipitation from west to east in Yili River Valley increases with the elevation of topography, and the frequency of weak precipitation increases. The precipitation distribution in the middle part of Tianshan Mountain shows the characteristics of low middle height on both sides and the highest frequency of weak precipitation at high altitude. In Tianshan area, the short-time precipitation events mainly occurred from the afternoon to the evening, which lasted for a short time, and the diurnal variation was also significantly affected by the topography. The peak value of precipitation in the Yili River Valley occurred in the evening to the night, when the precipitation occurred, the surface was mostly southwest wind and northeast wind, and the daily phase of precipitation in different regions of the middle part of Tianshan Mountain was different, and the peak value was in the evening on Tianshan Mountain. The north side (south side) is the peak value at night (early morning), and the main wind direction affecting precipitation in different regions is also different. The westerly wind and the northerly wind are dominant when the precipitation occurs on Tianshan Mountain, and the corresponding downhill wind direction is dominant on the north and south sides. Based on the analysis of the diurnal variation characteristics of summer precipitation in the middle segment of Tianshan Mountain, it is found that the diurnal variation of precipitation frequency and convective cloud frequency show three typical modes in the middle segment of Tianshan Mountain: the convection in the south side of Tianshan Mountain and the peak value of precipitation in the early morning. The peak of convection and precipitation occurred in the afternoon, and the peak time of convection and precipitation on the north side of Tianshan Mountain were both nocturnal. By defining the regional precipitation event (RRE) and screening the starting stations of the RRE, the diurnal variation characteristics of precipitation and the correlation between the diurnal variation characteristics of different regions are analyzed from the point of view of each precipitation event. The results show that the peak value of early morning precipitation on the southern side of Tianshan Mountain is isolated from the other two regions, resulting from the local precipitation events in the southern side. The afternoon peak of precipitation on Tianshan Mountain and the nocturnal peak of precipitation on the northern side of Tianshan Mountain are mainly caused by the contribution of precipitation events that started on Tianshan Mountain, and these precipitation events appear more frequently on Tianshan Mountain in the afternoon than on Tianshan Mountain in the afternoon. Then the northward movement resulted in the peak value of nocturnal precipitation in the northern basin. Based on the reanalysis data and WRF simulation results, the diurnal variation characteristics of the circulation in Tianshan region are analyzed. The convection triggered in the afternoon on Tianshan Mountain and in the south of Tianshan Mountain in the early morning is related to the diurnal variation of circulation field and thermal field in Tianshan Mountain and its surrounding area. In the afternoon, strong convergence at low level and the degree of thermodynamics instability appear on Tianshan Mountain, which is favorable to the triggering of convection on Tianshan Mountain, resulting in the afternoon peak value of Tianshan Mountain. The convergence center appeared in the southern Tianshan basin in the early morning, which combined with the thermodynamics instability energy in the southern side of the atmosphere, which was favorable to the triggering of convection on the southern side of Tianshan Mountain, resulting in the peak value of early morning precipitation on the southern side of Tianshan Mountain.
【学位授予单位】：中国气象科学研究院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P426.6
【相似文献】
相关期刊论文 前10条
1 杨又陵,曲延军;新疆天山地区定点形变群体异常特征与地震活动[J];地震;2002年01期
2 王树基;;我国天山自然条件的基本特点[J];地理科学;1991年01期
3 于湘伟;雷建设;石耀霖;张怀;;西南天山地区的地震重定位与活动性分析[J];中国科学院研究生院学报;2010年03期
4 关士聪;;天山的钢铁资源[J];地质论评;1948年Z1期
5 徐俊荣,仇家琪;天山地区影响稳定积雪形成的初始气候条件研究──以天山积雪雪崩研究站为例[J];干旱区地理;1996年04期
6 李佩基,李嵩龄,张志德;中国天山地区花岗岩类的基本特征[J];地球化学;1982年02期
7 牛之俊;游新兆;杨少敏;;利用GPS分析天山现今地壳形变特征[J];大地测量与地球动力学;2007年02期
8 王绍芳;郭宪璞;;天山地质考察记[J];大自然;1995年01期
9 杨少敏;李杰;王琪;;GPS研究天山现今变形与断层活动[J];中国科学(D辑:地球科学);2008年07期
10 袁方策,穆桂金,阎顺;中国天山地区的黄土[J];新疆地理;1983年04期
相关会议论文 前3条
1 孔祥儒;张凤玉;闫永利;马晓冰;刘宏兵;;天山地区电性结构特征研究[A];2001年中国地球物理学会年刊——中国地球物理学会第十七届年会论文集[C];2001年
2 郭育;肖兰喜;朱元清;;天山地区地震活动的相关性及初步解释[A];1998年中国地球物理学会第十四届学术年会论文集[C];1998年
3 郭卫英;;南天山地区两次红外增温现象与地震关系的讨论[A];中国地震学会第11次学术大会论文摘要集[C];2006年
相关硕士学位论文 前5条
1 安小艳;天山山区地形对降水空间分布的影响研究[D];石河子大学;2015年
2 陈nI茹;天山地区夏季降水的小时尺度特征[D];中国气象科学研究院;2017年
3 郭玉娣;青藏高原大地形“鱼尾”状地形热力效应对天山降水系统及水资源的影响[D];南京信息工程大学;2013年
4 傅嘉政;基于GPS和水准观测的天山地区垂直形变研究[D];中国地震局地震研究所;2014年
5 张萍;云卫星资料在天山山区降雨云研究中的应用[D];东华大学;2012年
，本文编号：2243739
本文链接：https://www.wllwen.com/shoufeilunwen/benkebiyelunwen/2243739.html
