EFFECTS OF TROPICAL CYCLONE TRACKS OVER THE WESTERN PACIFIC ON PRECIPITATION DURING MEIYU PERIOD IN JIANGHUAI FROM 2000 TO 2020
-
摘要: 选用2000—2020年自动站降水资料、热带气旋最佳路径数据集（CMA-STI）以及欧洲中期天气预报中心ERA5再分析资料，发现不到半数的热带气旋活动伴随江淮地区暴雨发生，且仅有3成的热带气旋存在时，江淮地区日降水达到当年梅雨期日均降水。除个别“转向型”及登陆后继续东移、北上的“西北型”热带气旋外，七成左右的热带气旋大多伴随有梅雨减弱现象，并利用WRF模式及热带气旋Bogus方法对2017年热带气旋“苗柏”和2019年热带气旋“丹娜丝”进行数值模拟，分析热带气旋的存在对梅雨季节降水的影响机制。结果表明：在模式能较好地模拟出两个热带气旋的路径及降水落区、强度的基础上，对比移除热带气旋前后的试验，西北路径的热带气旋“苗柏”登陆前，南缘偏西气流加强低空急流，江淮地区切变线加强，登陆后低压北抬，副高稳定，形成有利于降水的环流形势；剔除“苗柏”后，低空急流断裂，副高南退，水汽输送带南移，长江中下游地区降水减少。转向型热带气旋“丹娜丝”北移，伴随副高北抬，对流性不稳定减小，垂直上升运动减弱，西太平洋的水汽被大量输送到热带气旋中心附近，故输送至江淮地区的水汽减弱，降水减少，促使梅雨提前结束；而剔除“丹娜丝”影响后，副高稳定，东部降水增加，梅雨季尚能持续。Abstract: Based on the precipitation data of automatic weather stations, CMA-STI and ERA5 data from 2000 to 2020, this paper found that, less than half of the tropical cyclone activities were accompanied by heavy rain that occurred in the Jianghuai region, and only 30% of the tropical cyclones were in the company of daily precipitation in the Jianghuai area reaching the average daily amount in the Meiyu period of that year. Except for a few "path-turning type" tropical cyclones and "northwest-traveling type" tropical cyclones that continued to move eastward or northward after landfall, most of the other tropical cyclones were accompanied by the weakening of Meiyu. The WRF model and the built-in TC bogus method were used to simulate the 2017 typhoon Merbok and the 2019 typhoon Danas to verify the influence mechanism of TC on Meiyu. The results show that the model well simulated the path, precipitation area and intensity of the two typhoons. By comparing the tests before and after the removal of the typhoons, it was found that the "northwest-traveling type" typhoon Merbok strengthened a low-level jet with the westward airflow at the southern edge at the early stage, a Yangtze-Huaihe valley shear strengthened, a low pressure headed northward after landing, and a subtropical high was stable, forming a circulation situation favorable for precipitation. After removing Merbok, the low-level jet broke, the subtropical high retreated southward, the water vapor in the South China Sea could not be transported to the Yangtze-Huaihe valley, and the precipitation in the middle and lower reaches of the Yangtze River decreased. With the northward movement of both the path-turning type typhoon Danas and the the subtropical high, convective instability decreased and vertical ascending motion weakened. A large amount of water vapor from the western Pacific was transported to the vicinity of the typhoon eye. The water vapor transport and precipitation in the Yangtze-Huaihe valley decreased and the Meiyu was interrupted. After removing Danas, the precipitation in the east increased, the subtropical high was stable, and the Meiyu was maintained.
-
图 1 2000—2020年梅雨期4种路径热带气旋个数及其对应的江淮地区降水情况
黑色柱状为每种路径的热带气旋总数，蓝色柱状为每种路径带来一次暴雨及以上的热带气旋个数，红色柱状为每种路径带来降水量高于梅雨季节日均降水量的热带气旋个数
图 5 2017年6月11至13日控制试验CTL (a)和敏感试验SEN (b)模拟850 hPa低空急流（填色区域）、200 hPa高空急流(黑色实线）分布图（单位：m/s）
黑框为江淮区域。
图 10 2019年7月18日（a、d）、19日（b、e）以及20日（c、f）沿30 °N假相当位温经度-高度垂直剖面图（单位：K）
a~c为控制试验CTL，d~f为敏感试验。
图 11 7月18—20日控制试验CTL(a)和敏感试验SEN(b) 850 hPa平均水汽通量散度(阴影, 单位: 10-7 kg/(m2·s·hPa) 及风场(风矢, 单位: m/s)
黑色方框为江淮地区。
图 12 2019年7月18日（a、d）、19日（b、e）和20日（c、f）500 hPa日平均位势高度场（单位：dagpm）
a~c为控制试验CTL，d~f为敏感试验SEN。加粗黑线为588线。
-
[1] DING Y H, WANG Z Y, SUN Y. Inter-decadal variation of the summer precipitation in East China and its association with decreasing Asian summer monsoon. Part Ⅰ: Observed evidences[J]. International Journal of Climatology, 2008, 28(9): 1 139-1 161. [2] 刘芸芸, 丁一汇. 2020年超强梅雨特征及其成因分析[J]. 气象, 2020, 46(11): 1 393-1 404. [3] 刘长征, 薛峰. 不同强度El Niño的衰减过程. Ⅱ, 中等和较弱El Niño的衰减过程[J]. 地球物理学报, 2010, 53(11): 2 564-2 573. [4] 高辉. 南半球大气环流的季节和年际变化及其对东亚夏季风的影响[D]. 南京: 南京气象学院, 2004. [5] HUANG R H, HUANGPU J L, WU L, et al. Research on the interannual and interdecadal variabilities of the monsoon trough and their impacts on tropical cyclone genesis over the western north pacific ocean[J]. J Trop Meteor, 2018, 24(4): 395-420. [5] LIANG P, DING Y H, CENTER S C, et al. The Long-term Variation of extreme heavy precipitation and its link to urbanization effects in Shanghai during 1916-2014[J]. Adv Atmos Sci, 2017, 34(03): 321-334 [6] 黄荣辉, 陈光华. 西北太平洋热带气旋移动路径的年际变化及其机理研究[J]. 气象学报, 2007, 65(5): 683-694. [7] XIAN Z P, CHEN K Y. Numerical analysis on the effects of binary interaction between Typhoons Tembin and Bolaven in 2012[J]. Adv Meteor, 2019(1): 7529263. [8] 梁玉清, 陈文玉. 梅雨与热带气旋活动的关系[J]. 海洋预报, 2000, 17(4): 76-80. [9] 陈永林, 曹晓岗. 热带气旋及相关天气系统对上海强梅雨的影响分析[J]. 热带气象学报, 2006, 22(4): 326-330. [10] 朱哲, 钟中, 卢伟, 等. 一次热带气旋过程对出梅影响的数值模拟研究[J]. 大气科学学报, 2018, 41(2): 145-154 [11] 徐海明, 王谦谦, 葛朝霞. 9106号台风的热力作用对出梅影响的数值研究[J]. 热带气象学报, 1994, 10(3) : 231-237. [12] 中国气象局. GB/T 33671-2017梅雨检测指标[S]. 北京: 中国标准出版社 [13] MANSELL E R, ZIEGLER C L, BRUNING E C. Simulated electrification of a small thunderstorm with two-moment bulk microphysics[J]. J Atmos Sci, 2010, 67(1): 171-194. [14] MICHAEL J. IACONO, JENNIFER S, et al. Radiative forcing by long-lived greenhouse gases: Calculations with the AER radiative transfer models[J]. J Geophy Res, 2008, 113(d13): D13103-1-D13103-8-0. [15] TEWARI M, CHEN F, WANG W, et al. Implementation and verification of the unified NOAH land surface model in the WRF model[C]. 20th conference on weather analysis and forecasting/16th conference on numerical weather prediction, 2004. [16] HONG S Y, NOH Y, DUDHIA J. A new vertical diffusion package with an explicit treatment of entrainment processes[J]. Mon Wea Rev, 2005, 134(9): 2318. [17] KAIN J S, KAIN J. The Kain - Fritsch convective parameterization: An update[J]. J Applied Meteor, 2004, 43(1): 170-181. [18] CHEN S H, SUN W Y. A One-dimensional Time Dependent Cloud Model[J]. J Meteor Soc Japan, 2002, 80(1): 99-118. [19] QIAN Y, YASUNARI T J, DOHERTY S J, et al. Light-absorbing Particles in Snow and Ice: Measurement and Modeling of Climatic and Hydrological impact[J]. Adv Atmos Sci, 2015, 32(1): 28. [20] YANG Z L, NIU G Y, MITCHELL K E, et al. The community Noah land surface model with multiparameterization options (Noah-MP): 2. Evaluation over global river basins[J]. J Geophys Res, 2011, 116(D12): D12110. [21] JANJIC Z I. The Step-mountain Eta coordinate model: further developments of the convection, viscous sublayer, and turbulence closure schemes[J]. Mon Wea Rev, 1994, 122(5): 927-945. -
下载:
点击查看大图
图(12) / 表(2)
计量
- 文章访问数: 78
- HTML全文浏览量: 9
- PDF下载量: 29
- 被引次数: 0
粤公网安备 4401069904700003号