By using the NCEP 1°×1° reanalysis daily datasets, the dynamic and thermal three-dimensional structure and evolution characteristics of a central Asian vortex causing rainstorm during 4 to 7 September 2009 were analyzed, and its development mechanisms were discussed. The results indicated that the vortex had an obvious cold core structure and developed strongly, which developed at the upper firstly (its center and evolution characteristics were evident on 300 hPa) and extended downward with time, its development-mature-weakened process was a baroclinic-barotropic-baroclinic process. In mature stage, cold center coincided with height center with the axis tending to be vertical; there was a positive vorticity center on both western and eastern flank of vortex center on 300 hPa which were symmetrical and the vorticity almost was positive in troposphere; the lower troposphere was convergence while the upper troposphere was divergence, making conditions favorable for ascending motion and vortex development. In weaken period, the axis-line tilted toward the west and cold center declined significantly; there was negative vorticity in the middle and upper troposphere and no obviously divergence/convergence and ascending motion in almost all of troposphere over vortex center. During this process, ascend motion combined with ample water vapor condition causing the heavy precipitation. The “upper dry, lower wet” spatial structure in troposphere, the cold air moved downward as well as the intrusion and downward motion of high potential vorticity were conducive to the development of this vortex and played a significant role in its development and evolution.
LI Man
,
YANG Lianmei
,
ZHANG Yunhui
. Dynamic and Thermal Structure and Evolution Characteristics of a Central Asian Vortex[J]. Plateau Meteorology, 2015
, 34(6)
: 1711
-1720
.
DOI: 10.7522/j.issn.1000-0534.2014.00077
[1]张家宝, 苏起元, 孙沈清. 新疆短期天气预报指导手册[M]. 乌鲁木齐: 新疆人民出版社, 1986: 1-465.
[2]张家宝, 邓子风. 新疆降水概论[M]. 北京: 气象出版社, 1987: 1-400.
[3]杨莲梅. 南亚高压突变引起的一次新疆暴雨天气研究[J]. 气象, 2003, 29(8): 21-25.
[4]张云惠, 杨莲梅, 肖开提·多莱特, 等. 1971-2010年中亚低涡活动特征[J]. 应用气象学报, 2012, 23(3): 312-321.
[5]江远安, 包斌, 王旭. 南疆西部大降水天气过程的统计分析[J]. 新疆气象, 2001, 24(5): 19-20.
[6]杨莲梅, 李霞, 张广兴. 新疆夏季强降水研究若干进展及问题[J]. 气候与环境研究, 2011, 16(2): 188-198.
[7]王磊, 李荣欣, 江远安. “96·7”南疆西部大降水分析[J]. 新疆气象, 1997, 20(1): 28-30.
[8]张云惠, 王勇. 哈密南部暴雨成因分析[J]. 气象, 2004, 30(7): 41-43.
[9]杨莲梅, 张庆云. 新疆北部汛期降水年际和年代际异常的环流特征[J]. 地球物理学报, 2007, 50(2): 412-419.
[10]张云惠, 陈春艳, 杨莲梅, 等. 南疆西部一次罕见暴雨过程的成因分析[J]. 高原气象, 2013, 32(1): 191-200, doi: 10.7522/j.issn.1000-0534.2013.00019.
[11]Yu Yaxun, Wu Guoxiong. Water vapor content and its mean transfer in the atmosphere over Northwest China[J]. Acta Meteor Sini, 2001, 15(2): 191-204.
[12]肖开提·多莱特. 新疆降水量级标准的划分[J]. 新疆气象, 2005, 28(3): 7-8.
[13]郁珍艳, 何立富, 李泽椿. 一次华北冷涡动力热力结构及发展机制分析[J]. 气象科学, 2011, 31(6): 667-676.
[14]刘英, 王东海, 张中锋, 等. 东北冷涡的结构及其演变特征的个例综合分析[J]. 气象学报, 2012, 70(3): 354-370.
[15]Hoskins B J, McIntyre M E, Robertson A W. On the use and significance of isentropic potential vorticity maps[J]. Quart J Roy Meteor Soc, 1985, 111(470): 877-946.
[16]寿绍文. 位涡理论及其应用[J]. 气象, 2010, 36(3): 9-18.
[17]盛裴轩, 毛节泰, 李建国, 等. 大气物理学[M]. 北京: 北京大学出版社, 2003: 18-24.
[18]钟水新, 王东海, 张人禾, 等. 一次东北冷涡降水过程的机构特征及影响因子分析[J]. 高原气象, 2011, 30(2): 951-960.
[19]郑媛媛, 张雪晨, 朱红芳, 等. 东北冷涡对江淮飑线生成的影响研究[J]. 高原气象, 2014, 33(1): 261-269, doi: 10.7522/j.issn.1000-0534.2013.00005.
[20]吴迪, 姚秀萍, 寿绍文. 干侵入对一次东北冷涡过程的作用分析[J]. 高原气象, 2010, 29(5): 1208-1217.
[21]梁红丽, 段旭, 符睿, 等. 影响云南的西南低涡统计特征[J]. 高原气象, 2013, 31(4): 1066-1073, doi: 10.7522/j.issn.1000-0534.2013.00076.
[22]江玉华, 杜钦, 赵大军, 等. 引发四川盆地东部暴雨的西南低涡结构特征研究[J]. 高原气象, 2012, 31(6): 1562-1573.
[23]康岚, 郝丽萍, 牛俊丽. 引发暴雨的西南低涡特征分析[J]. 高原气象, 2011, 30(6): 1435-1443.
[24]翟丹华, 刘德, 李强, 等. 引发重庆中西部暴雨的西南涡特征分析[J]. 高原气象, 2014, 33(1): 140-147, doi: 10.7522/j.issn.1000-0534.2012.00181.