甘肃北部短时强降水中尺度特征及物理量配置

doi:10.12118/j.issn.1000-6060.2022.067

摘要/Abstract

摘要：

利用甘肃北部27个国家级自动气象站及635个区域气象站降水资料，结合常规高空、地面和欧洲中期天气预报中心（ECMWF）再分析物理量场资料，选取了2016—2019年5—9月104个典型短时强降水个例，对甘肃北部短时强降水天气发生发展的环境条件进行了中尺度综合分析，揭示了区域内短时强降水的一些特征和规律。结果表明：（1）甘肃北部短时强降水集中出现在6—8月，短时强降水的强度多为10~20 mm。（2）甘肃北部短时强降水天气的典型特征，分为副高边缘型、低压槽型、西北气流型和河套阻高型4种流型。（3）通过分析不同天气形势、不同类别、不同物理量参数间的联系与区别，总结出各类短时强降水天气的环流特征和物理量要素指标和阈值。（4）地面辐合线（冷锋）是甘肃北部触发强对流天气的关键系统，地面辐合线（冷锋）的分析对短时临近预报至关重要。（5）低空偏南风急流（显著流线）在110°E左右北上及在37°N左右产生辐合是判断甘肃北部能否产生短时强降水的重要依据。并对2020年短时强降水预报效果进行检验，预报准确率达63.6%，说明建立的短时强降水预报指标预报能力较强，为提高短时强降水预报预警能力提供了一种新途径。

关键词: 短时强降水, 天气类型, 中尺度分析, 物理量, 要素配置

Abstract:

From the precipitation data of 27 national automatic weather stations and 635 regional weather stations in northern Gansu Province of China, combined with the conventional air, ground, and ECMWF reanalysis data, 104 cases of typical short-time heavy rainfall from May to September during 2016—2019 were selected. In this paper, mesoscale comprehensive analysis of environmental conditions for the occurrence and development of short-time heavy rainfall in northern Gansu Province was performed, and some characteristics and laws of short-time heavy rainfall in this region were revealed. The results show the following: (1) The short-time heavy rainfall in northern Gansu Province primarily occurs from June to August, and the intensity of short-time heavy rainfall is mostly 10-20 mm. (2) The typical characteristics of short-time heavy rainfall weather in northern Gansu Province can be divided into four flow types: subtropical high marginal type, low-pressure trough type, northwest airflow type, and high flow resistance type. (3) The relation and difference between different weather conditions, flow types, and physical parameters are discussed. The circulation characteristics and physical factors indexes and thresholds of various short-time heavy rainfall weather are summarized. (4) The surface convergence line (cold front) is the key system triggering severe convective weather in northern Gansu Province, and the analysis of the surface convergence line (cold front) is critical for short-time near rainfall forecast. (5) Low-level southerly jet (significant streamline) convergence at 110°E and 37°N is an important basis for judging whether short-time heavy rainfall can occur in northern Gansu Province. The prediction accuracy of short-time heavy rainfall in 2020 is 63.6%, indicating that the established short-time heavy rainfall forecast index has a strong capability, providing a new way to improve the short-time heavy rainfall forecast and early warning ability.

Key words: short-time heavy rainfall, weather types, mesoscale analysis, physical quantity, factors allocation

钱莉,张春燕,杨梅,李天江. 甘肃北部短时强降水中尺度特征及物理量配置[J]. 干旱区地理, 2022, 45(6): 1707-1717.

QIAN Li,ZHANG Chunyan,YANG Mei,LI Tianjiang. Mesoscale characteristics and physical quantity allocation of short-time heavy rainfall in northern Gansu Province[J]. Arid Land Geography, 2022, 45(6): 1707-1717.

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参考文献 19

[1]	俞小鼎. 基于构成要素的预报方法[J]. 气象, 2011, 37(8): 913-918.
	[Yu Xiaoding. Ingredients based forecasting methodology[J]. Meteorological Monthly, 2011, 37(8): 913-918.]
[2]	俞小鼎, 周晓刚, 王秀明. 雷暴与强对流临近天气预报技术进展[J]. 气象学报, 2012, 70(3): 311-337.
	[Yu Xiaoding, Zhou Xiaogang, Wang Xiuming. The advances in the nowcasting techniques on thunderstorms and severe convection[J]. Acta Meteorologica Sinica, 2012, 70(3): 311-337.]
[3]	孙继松, 戴建华, 何立富, 等. 强对流天气预报的基本原理与技术方法——中国强对流天气预报手册[M]. 北京: 气象出版社, 2014.
	[Sun Jisong, Dai Jianhua, He Lifu, et al. Basic principles and technical methods of severe convective weather forecast: Handbook of severe convective weather forecast in China[M]. Beijing: Meteorological Press, 2014.]
[4]	Doswell Ⅲ C A, Brooks H E, Maddox R A. Flash flood forecasting: An ingredients-based methodology[J]. Weather and Forecasting, 1996, 11(4): 560-581. doi: 10.1175/1520-0434(1996)011＜0560:FFFAIB＞2.0.CO;2
[5]	郑媛媛, 姚晨, 郝莹, 等. 不同类型大尺度环流背景下强对流天气的短时临近预报预警研究[J]. 气象, 2011, 37(7): 795-801.
	[Zheng Yuanyuan, Yao Chen, Hao Ying, et al. The short-time forecasting and early-warning reasearch on severe convective weather under different types of large-scale circulation background[J]. Meteorological Monthly, 2011, 37(7): 795-801.]
[6]	徐爱华, 孙继松, 徐东蓓, 等. 中国中东部强对流天气形势分类和基本要素配置特征[J]. 气象, 2014, 40(4): 400-411.
	[Xu Aihua, Sun Jisong, Xu Dongbei, et al. Basic synoptic situation classification and element character of severe convection in China[J]. Meteorological Monthly, 2014, 40(4): 400-411.]
[7]	白晓平, 王式功, 赵璐, 等. 西北地区东部短时强降水概念模型[J]. 高原气象, 2016, 35(5): 1248-1256. doi: 10.7522/j.issn.1000-0534.2015.00102
	[Bai Xiaoping, Wang Shigong, Zhao Lu, et al. Conceptual models of short-time heavy rainfall in the east of northwest China[J]. Plateau Meteorology, 2016, 35(5): 1248-1256.] doi: 10.7522/j.issn.1000-0534.2015.00102
[8]	张一萍, 吴蓁, 苏爱芳, 等. 基于流型识别和物理量要素分析河南强对流天气特征[J]. 高原气象, 2013, 32(5): 1492-1502. doi: 10.7522/j.issn.1000-0534.2012.00139.
	[Zhang Yiping, Wu Zhen, Su Aifang, et al. Analysis on severe convective weather characteristic in Henan based on flow pattern identification and physical elements[J]. Plateau Meteorology, 2013, 32(5): 1492-1502.] doi: 10.7522/j.issn.1000-0534.2012.00139.
[9]	周后福, 邱明燕, 张爱民, 等. 基于稳定度和能量指标作强对流天气的短时预报指标分析[J]. 高原气象, 2006, 25(4): 716-722.
	[Zhou Houfu, Qiu Mingyan, Zhang Aimin, et al. Analysis on short-time forecast of severe convection weather based on stability and energy indexes[J]. Plateau Meteorology, 2006, 25(4): 716-722.]
[10]	刘国忠, 黄开刚, 罗建英, 等. 基于概念模型及配料法的持续性暴雨短期预报技术研究[J]. 气象, 2013, 39(1): 20-27.
	[Liu Guozhong, Huang Kaigang, Luo Jianying, et al. Research on the short term forecasting technique of persistent rainstorm with conceptual model and ingredients based method[J]. Meteorological Monthly, 2013, 39(1): 20-27.]
[11]	何钰, 陈小华, 杨素雨, 等. 基于“配料法”的云南短时强降水预报概念模型建立[J]. 气象, 2018, 44(12): 1542-1554.
	[He Yu, Chen Xiaohua, Yang Suyu, et al. Forecast conceptual model establishment of short time severe rainfall on Yunnan based on the “ingredients”[J]. Meteorological Monthly, 2018, 44(12): 1542-1554.]
[12]	孔祥伟, 杨建才, 李红, 等. 甘肃河东地区不同环流形势下短时强降水的雷达回波特征分析[J]. 高原气象, 2021, 40(5): 1057-1070. doi: 10.7522/j.issn.1000-0534.2020.00084
	[Kong Xiangwei, Yang Jiancai, Li Hong, et al. Analysis of radar echo characteristics of short-term heavy precipitation weather with different circulation pattern in east Gansu Province[J]. Plateau Meteorology, 2021, 40(5): 1057-1070.] doi: 10.7522/j.issn.1000-0534.2020.00084
[13]	王俊, 王文青, 王洪, 等. 短时强降水和冰雹云降水个例雨滴谱特征分析[J]. 高原气象, 2021, 40(5): 1071-1086. doi: 10.7522/j.issn.1000-0534.2020.00091
	[Wang Jun, Wang Wenqing, Wang Hong, et al. Characteristics of the raindrop size distribution during a short-time heavy rainfall and a squall line accompanied by hail[J]. Plateau Meteorology, 2021, 40(5): 1071-1086.] doi: 10.7522/j.issn.1000-0534.2020.00091
[14]	陶健红, 孔祥伟, 刘新伟. 河西走廊西部两次极端暴雨事件水汽特征分析[J]. 高原气象, 2016, 35(1): 107-117. doi: 10.7522/j.issn.1000-0534.2014.00144
	[Tao Jianhong, Kong Xiangwei, Liu Xinwei. Analysis on water vapor characteristics of two extreme rainstorm events in western Gansu corridor[J]. Plateau Meteorology, 2016, 35(1): 107-117.] doi: 10.7522/j.issn.1000-0534.2014.00144
[15]	李建刚, 姜彩莲, 张云惠, 等. 中亚低涡背景下一次短时强降水过程MCS成因分析[J]. 干旱区地理, 2019, 42(4): 724-734.
	[Li Jiangang, Jiang Cailian, Zhang Yunhui, et al. Causal analysis of MCS in a short time severe precipitation process under the background of Central Asia vortex[J]. Arid Land Geography, 2019, 42(4): 724-734.]
[16]	王昀, 卢品睿, 王旭. 天山南侧喀什地区冰雹潜势预报及预警指标的研究[J]. 干旱区地理, 2018, 41(5): 937-944.
	[Wang Yun, Lu Pinrui, Wang Xu. Nowcasting indicators of radar of hail cloud in southern Tianshan Mountains[J]. Arid Land Geography, 2018, 41(5): 937-944.]
[17]	钱莉, 杨永龙, 张宇林, 等. 河西走廊东部极端降水的时空分布及影响因子分析[J]. 干旱区地理, 2015, 38(2): 207-214.
	[Qian Li, Yang Yonglong, Zhang Yulin, et al. Temporal and spatial distribution and influence factors of extreme precipitation in eastern Hexi Corridor[J]. Arid Land Geography, 2015, 38(2): 207-214.]
[18]	钱莉, 方锋, 杨永龙, 等. 河西走廊东部冰雹的气候特征及天气特征[J]. 干旱区研究, 2013, 30(1): 50-55.
	[Qian Li, Fang Feng, Yang Yonglong, et al. Analysis on hail and weather characteristics in the east Hexi Corridor, Gansu Province[J]. Arid Zone Research, 2013, 30(1): 50-55.]
[19]	黄玉霞, 王宝鉴, 王勇, 等. 甘肃省强对流天气中尺度分析业务技术规范[M]. 北京: 气象出版社, 2017.
	[Huang Yuxia, Wang Baojian, Wang Yong, et al. Technical specification for mesoscale analysis of severe convective weather in Gansu Province[M]. Beijing: Meteorological Press, 2017.]

物理量阈值		副高边缘型	低压槽型	西北气流型	河套阻高型
抬升条件	500 hPa槽前	是	是	否	是
	中低层低涡切变	有	有	有	有
	地面辐合线	有	有	有	有
	低空辐合	有	有	有	有
	200 hPa急流	西风急流或分流区	西北风急流	西北风急流或分流区	西风急流
水汽条件	t₇₀₀-td₇₀₀/℃	≤4	≤4	≤7	≤4
	q₇₀₀/g·kg^-1	≥8	≥7	≥5	≥8
	qfdiv₇₀₀/g·hPa^-1·cm^-2·s^-1	≤-10	≤-2	≤-1	≤-1
	湿层/hPa	500~850	500~850	500~700	500~850
	低空偏南风急流（显著流线）	有	有	有	有
	θ_se700/℃	≥60	≥60	≥52	≥55
不稳定条件	温度垂直分布	上冷下暖	上冷下暖	上冷下暖	上冷下暖
	湿度垂直分布	深厚湿层	深厚湿层	上干下湿	深厚湿层
	t₇₀₀-t₅₀₀/℃	≥20	≥20	≥20	≥20
	CAPE/J·kg^-1	≥29	≥20	≥40	≥50
	K/℃	≥30	≥30	≥28	≥32
	VOR₇₀₀/10^-5·s^-1	≥2	≥5	≥2	≥12

物理量阈值		副高边缘型（2018-08-02）	低压槽型（2017-08-19）	西北气流型（2018-08-20）	河套阻高型（2019-06-20）
抬升条件	500 hPa槽前	是	是	否	是
	中低层低涡切变	切变线	切变线	低涡人字型切变	低涡人字型切变
	地面辐合线	有	冷锋	有	有
	低空辐合	偏北风与偏南风辐合	偏南风、偏东风与偏北风辐合	偏南风与偏北风辐合	西南风与东南风辐合
	200 hPa急流	分流区	西风急流入口区右侧	分流区	西风急流出口区左侧
水汽条件	t₇₀₀-td₇₀₀/℃	≤4	≤4	≤4	≤4
	q₇₀₀/g·kg^-1	8	10	8	8
	qfdiv₇₀₀/g·hPa^-1·cm^-2·s^-1	-20	-20	-10	-1
	湿层/hPa	500~850	500~850	700~850	500~850
	低空偏南风急流（显著流线）	有	有	有	有
	θ_se700/℃	76	72	68	64
不稳定条件	温度垂直分布	上冷下暖	上冷下暖	上冷下暖	上冷下暖
	湿度垂直分布	深厚湿层	深厚湿层	上干下湿	深厚湿层
	t₇₀₀-t₅₀₀/℃	≥20	≥20	≥20	≥20
	CAPE/J·kg^-1	132	224	440	50
	K/℃	36	32	36	32
	VOR₇₀₀/10^-5·s^-1	20	5	5	40

城市	副高边缘型		低压槽型		西北气流型		河套阻高型
城市	频次/次	频率/%	频次/次	频率/%	频次/次	频率/%	频次/次	频率/%
兰州市	24	42.1	12	25.5	9	34.6	11	26.2
白银市	19	33.3	15	31.9	10	38.5	8	19.0
武威市	8	14.0	10	21.3	3	11.5	9	21.4
张掖市	4	7.0	8	17.0	1	3.8	8	19.0
酒泉市	2	3.5	2	4.3	3	11.5	6	14.3