Environmental Characteristics of Extratropical Cyclone Tornadoes in Liaoning

Bai Hua; Yuan Chao; Pan Xiao; Yang Lei; Li Deqin

doi:10.11898/1001-7313.20230109

Vol.34, NO.1, 2023

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Article Navigation > Journal of Applied Meteorological Science > 2023 > 34(1): 104-116

Bai Hua, Yuan Chao, Pan Xiao, et al. Environmental characteristics of extratropical cyclone tornadoes in Liaoning. J Appl Meteor Sci, 2023, 34(1): 104-116. DOI: 10.11898/1001-7313.20230109.

Citation:

Bai Hua, Yuan Chao, Pan Xiao, et al. Environmental characteristics of extratropical cyclone tornadoes in Liaoning. J Appl Meteor Sci, 2023, 34(1): 104-116. DOI: 10.11898/1001-7313.20230109.

Bai Hua, Yuan Chao, Pan Xiao, et al. Environmental characteristics of extratropical cyclone tornadoes in Liaoning. J Appl Meteor Sci, 2023, 34(1): 104-116. DOI: 10.11898/1001-7313.20230109.

Citation:

Bai Hua, Yuan Chao, Pan Xiao, et al. Environmental characteristics of extratropical cyclone tornadoes in Liaoning. J Appl Meteor Sci, 2023, 34(1): 104-116. DOI: 10.11898/1001-7313.20230109.

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Environmental Characteristics of Extratropical Cyclone Tornadoes in Liaoning

DOI: 10.11898/1001-7313.20230109

Bai Hua^{1, 2, 3, 4},
Yuan Chao^{1, 5
,
,},
Pan Xiao¹,
Yang Lei^{1, 6},
Li Deqin¹

1.
Institute of Atmospheric Environment, China Meteorological Administration, Shenyang 110166
2.
Shenyang Meteorological Bureau of Liaoning, Shenyang 110068
3.
College of Agronomy, Shenyang Agricultural University, Shenyang 110866
4.
Kangping Meteorological Bureau of Liaoning, Shenyang 110500
5.
Panjin Meteorological Bureau of Liaoning, Panjin 124010
6.
Liaoning Warning Center of Meteorological Disaster Monitoring, Shenyang 110166

Received Date: 2022-07-27
Rev Recd Date: 2022-10-24
Publish Date: 2023-01-31

Abstract

Abstract

Liaoning is one of the active regions for tornadoes in China, and the generation of a considerable number of tornadoes is associated with extratropical cyclones. In order to improve the understanding of environmental background and physical parameter characteristics, 42 extratropical cyclone tornadoes in Liaoning from 1979 to 2020 are statistically analyzed. The study is based on the reanalysis data of ERA5(ECMWF Reanalysis V5), combining with records of China Meteorological Disaster Classic and China Meteorological Disaster Yearbook. Results show that extratropical cyclone tornadoes are mainly distributed in the central and western Liaohe Plain and along the coast of the Bohai Bay. Significant tornadoes(EF2 and above) account for 28.6% of all extratropical cyclone tornadoes.Extratropical cyclone tornadoes occur mostly in the southwest and southeast quadrants of extratropical cyclones, corresponding to the warm area before the cold front. The high-value area of the storm relative helicity and convective available potential energy(CAPE) appear in the southwest-southeast quadrant of the extratropical cyclones, with a belt-like distribution. Extratropical cyclone tornadoes are mainly distributed within 1° of latitude in the northwest of the large-value area of storm relative helicity and the strong gradient area at the top of the large-value area of CAPE. The strong tornado parameter(STP) center is located near the -2° of longitude distance and -5° of latitude distance from the center of tornadic extratropical cyclones, and the maximum value is above 0.7. The large value area of STP corresponds to the high-incidence area of EF2 and above extratropical cyclone tornadoes. The cold front and dry line in the surface are the key trigger of extratropical cyclone tornadoes, and the induced tornadoes are mainly distributed near the warm ridge of temperature field and the top of the tongue of humidity field. Comparing the vertical distribution of humidity near the center of tornadic extratropical cyclones and the tail of the cold front, the strong cold pool caused by the strong high-level dry intrusion can generate excessively strong downdraft, which may be an unfavorable factor for tornado formation. Extratropical cyclone tornadoes are mostly distributed in the distributary area of the left air flow of the upper-level jet, corresponding to the strong upper-level divergence area. The large value area of 0-3 km vertical temperature lapse rate has a good correspondence with the high incidence area of weak tornadoes near the center of extratropical cyclones.
- tornado;
- extratropical cyclone;
- environmental parameters;
- Liaoning

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References(53)

Figures and Tables

Fig. 1 Sounding and ERA5 at Jinzhou Station from Jun to Aug in 2020

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图 2 1979—2020年辽宁省温带气旋龙卷分布

(填色为海拔高度；蓝色标记为龙卷)

Fig. 2 Distribution of extratropical cyclone tornado in Liaoning from 1979 to 2020

(the shaded denotes altitude;the blue mark denotes tornado)

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图 3 龙卷相对温带气旋中心分布

(黑色等值线为900 hPa位势高度，单位：dagpm；风羽为900 hPa风场；填色为900 hPa相对涡度；蓝色标记为龙卷；蓝色等值线为龙卷分布的核密度估计，最内圈为90%，最外圈为10%；气旋中心位于(0, 0))

Fig. 3 Spatial distribution of tornado relative to the center of extratropical cyclone

(the black isoline denotes the height at 900 hPa, unit:dagpm;the barb denotes wind at 900 hPa; the shaded denotes relative vorticity at 900 hPa; the blue mark denotes tornado;the blue isoline denotes the kernel density estimation of tornadoes, the innermost(outermost) circle is 90%(10%); the center of extratropical cyclone is located at (0, 0))

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图 4 产生龙卷的温带气旋附近的0~1 km风暴相对螺旋度(填色) 分布

(黑色等值线为900 hPa位势高度，单位：dagpm；风羽为900 hPa风场；蓝色标记为龙卷；气旋中心位于(0, 0))

Fig. 4 Distribution of 0-1 km storm relative helicity (the shaded) near tornadic extratropical cyclone

(the black isoline denotes the height at 900 hPa, unit:dagpm;the barb denotes wind at 900 hPa; the blue mark denotes tornado;the center of extratropical cyclone is located at (0, 0))

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图 5 产生龙卷的温带气旋附近对流有效位能(填色) 分布

(其他说明同图 4)

Fig. 5 Distribution of convective available potential energy (the shaded) near tornadic extratropical cyclone

(the others same as in Fig. 4)

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图 6 温带气旋附近的强龙卷参数(填色) 分布

(其他说明同图 4)

Fig. 6 Distribution of strong tonado parameter (the shaded) near tornadic extratropical cyclone

(the others same as in Fig. 4)

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图 7 产生龙卷的温带气旋附近地面2 m温度(填色) (a)、2 m露点(填色) (b)分布

(黑色等值线为海平面气压场，单位：hPa；风羽为地面10 m风场；蓝色标记为龙卷；气旋中心位于(0, 0))

Fig. 7 Distribution of temperature at 2 m (the shaded) (a), dew point temperature at 2 m (the shaded) (b) near tornadic extratropical cyclone

(the black isoline denotes the sea level pressure, unit:hPa;the barb denotes the wind at 10 m; the blue mark denotes tornado;the center of extratropical cyclone is located at (0, 0))

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图 8 沿图 7a中AA′(a)及BB′(b)的空间垂直剖面

(红色等值线为温度，单位：℃；黑色等值线为垂直速度，单位：10 Pa·s^-1；填色代表相对湿度)

Fig. 8 Spatial vertical section along AA′(a) and BB′(b) in Fig. 7a

(the red isoline denotes temperature, unit:℃;the black isoline denotes the vertical speed, unit:10 Pa·s^-1;the shaded denotes the relative humidity)

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图 9 产生龙卷的温带气旋附近200 hPa形势场

(黑色等值线为200 hPa位势高度，单位:dagpm；棕色等值线为200 hPa等风速线，单位:m·s^-1；蓝色等值线为90%龙卷核密度分布估计；风矢为200 hPa风场；填色为200 hPa散度)

Fig. 9 Distribution of weather situation field at 200 hPa near tornadic extratropical cyclone

(the black isoline denotes the height at 200 hPa, unit:dagpm;the brown isoline denotes the velocity at 200 hPa, unit:m·s^-1;the blue isoline denotes 90% kernel density estimation of tornadoes; the vector denotes the wind at 200 hPa; the shaded denotes the divergence at 200 hPa)

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图 10 产生龙卷的温带气旋附近地面至3 km高度温差(填色)

(其他说明同图 4)

Fig. 10 Distribution of temperature difference from ground to 3 km (the shaded) near tornadic extratropical cyclone

(the others same as in Fig. 4)

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Fig. 11 Typical synoptic patterns of extratropical cyclone tornado in Liaoning

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Table 1 Extratropical cyclone tornado in Liaoning from 1979 to 2020

序号	时间	龙卷发生地	强度等级	来源
1	1980-06-20	兴城	EF2	《中国气象灾害大典》(辽宁卷)
2	1980-07-21	辽阳县	EF2	《中国气象灾害大典》(辽宁卷)
3	1983-07-04	瓦房店	EF0	地面观测
4	1983-07-21	瓦房店	EF1	《中国气象灾害大典》(辽宁卷)
5	1983-09-14	普兰店	EF1	《中国气象灾害大典》(辽宁卷)
6	1983-09-14	绥中	EF2	《中国气象灾害大典》(辽宁卷)
7	1984-05-27	义县	EF2	县级历史气象灾情收集资料
8	1984-06-09	喀左	EF0	县级历史气象灾情收集资料
9	1985-06-10	建昌	EF0	县级历史气象灾情收集资料
10	1986-07-14	苏家屯	EF2	《辽宁省志》(气象志)
11	1986-07-14	黑山	EF2	《辽宁省志》(气象志)
12	1986-07-14	葫芦岛	EF1	县级历史气象灾情收集资料
13	1986-07-22	阜新县	EF0	县级历史气象灾情收集资料
14	1986-08-08	康平	EF2	县级历史气象灾情收集资料
15	1986-08-12	阜新县	EF1	县级历史气象灾情收集资料
16	1987-06-19	朝阳县	EF1	县级历史气象灾情收集资料
17	1987-07-13	营口	EF0	地面观测
18	1988-09-06	北票	EF1	《辽宁省志》(气象志)
19	1988-09-06	阜新县	EF2	《辽宁省志》(气象志)
20	1989-06-24	阜新县	EF1	县级历史气象灾情收集资料
21	1989-05-18	阜新县	EF1	县级历史气象灾情收集资料
22	1990-06-22	大洼	EF1	县级历史气象灾情收集资料
23	1990-08-12	辽阳县	EF3	《辽宁省志》(气象志)
24	1991-07-15	阜新县	EF0	县级历史气象灾情收集资料
25	1992-08-10	黑山	EF2	《辽宁省志》(气象志)
26	1993-06-06	葫芦岛	EF1	县级历史气象灾情收集资料
27	1993-06-07	新民	EF0	县级历史气象灾情收集资料
28	1993-08-12	彰武	EF1	县级历史气象灾情收集资料
29	1996-09-19	庄河	EF1	县级历史气象灾情收集资料
30	1998-05-26	康平	EF1	县级历史气象灾情收集资料
31	2000-07-13	葫芦岛	EF1	县级历史气象灾情收集资料
32	2000-08-23	黑山	EF1	县级历史气象灾情收集资料
33	2002-07-31	辽中	EF1	地面观测
34	2005-06-01	绥中	EF1	县级历史气象灾情收集资料
35	2005-06-10	朝阳县	EF3	《中国气象灾害年鉴》
36	2005-06-11	沈阳	EF0	县级历史气象灾情收集资料
37	2005-07-01	盘山	EF0	县级历史气象灾情收集资料
38	2005-08-10	盖州	EF1	县级历史气象灾情收集资料
39	2010-07-27	彰武	EF1	县级历史气象灾情收集资料
40	2012-06-04	铁岭县	EF2	县级历史气象灾情收集资料
41	2012-07-02	大连	EF0	县级历史气象灾情收集资料
42	2013-09-06	大连	EF0	县级历史气象灾情收集资料

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