城市下垫面对西安地区一次强降水的影响
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摘要
针对2015年8月3日发生在西安地区的一次强降水,首先利用WRF-3DVAR同化系统循环同化雷达反射率和径向风资料来减小模式初始场误差,以此增加基于模式预报结果分析研究的可信度,然后采用敏感试验手段探究有无城市下垫面对西安地区强对流性天气的影响。结果表明,同化雷达资料可以改善降水预报,其中10～25 mm降水TS (True Shooting)和ETS (Effective True Shooting)评分较未同化结果分别提高0. 188和0. 187,降水落区和强度与观测接近。有无城市下垫面的对比试验发现,有城市时,城区平均对流有效位能增大而对流抑制能减小,低层风速减小,城区上空假相当位温的垂直梯度变大,大气更加不稳定。城市下垫面使城区降水增强,若用农田代替城市下垫面会使降水落区向南漂移约0. 2个纬距。
On August 3,2015,a heavy rainfall occurred in Xi'an with floods and heavy losses. To better investigate the rainfall,highly temporal and spatial resolution radar data,mesoscale WRF model and its 3 DVAR assimilation system were used. After assimilating the radar data,the precipitation area and intensity were improved,and the TS( True Shooting) and ETS( Effective True Shooting) scores of 10～25 mm precipitation increased respectively by 0. 188 and 0. 187 compared with no data assimilation. Then two experiments with and without urban surface( CITY and NoCITY) were carried out to explore the impact of urban surface on forecast of precipitation.In CITY,the average convective available potential energy( CAPE) increased and the convective inhibition energy( CIN) reduced,low-level wind speed became smaller,and vertical gradient of the pseudo-specific temperature was larger and the atmospheric became more unstable than those in NoCITY. The urban surface enhanced precipitation over the urban area; if the urban surface was substituted by a cultivated land,the precipitation area would shift southward approximately. 2 latitudes.
On August 3,2015,a heavy rainfall occurred in Xi'an with floods and heavy losses. To better investigate the rainfall,highly temporal and spatial resolution radar data,mesoscale WRF model and its 3 DVAR assimilation system were used. After assimilating the radar data,the precipitation area and intensity were improved,and the TS( True Shooting) and ETS( Effective True Shooting) scores of 10～25 mm precipitation increased respectively by 0. 188 and 0. 187 compared with no data assimilation. Then two experiments with and without urban surface( CITY and NoCITY) were carried out to explore the impact of urban surface on forecast of precipitation.In CITY,the average convective available potential energy( CAPE) increased and the convective inhibition energy( CIN) reduced,low-level wind speed became smaller,and vertical gradient of the pseudo-specific temperature was larger and the atmospheric became more unstable than those in NoCITY. The urban surface enhanced precipitation over the urban area; if the urban surface was substituted by a cultivated land,the precipitation area would shift southward approximately. 2 latitudes.
引文
Barker D M,Huang X Y,Liu Z Q,et al,2012.The Weather Research and Forecastion(WRF)model's community variational/ensemble data assimilation system:WRFDA[J].Bulletin of the American M eteorological Society,93(6):831-843.DOI:10.1175/BAM S-D-11-00167.1.
Daniels E E,Hutjes R W A,Lenderink G,et al,2015.Land surface feedbacks on spring precipitation in the Netherlands[J].Journal of Hydrometeorology,16(1):232-243.DOI:10.1175/JHM-D-14-0072.1.
Lin C Y,Chen W C,Liu S C,et al,2008.Numerical study of the impact of urbanization on the precipitation over Taiw an[J].Atmospheric Environment,42(13):2934-2947.DOI:10.1016/j.atmosenv.2007.12.054.
Loveland T R,Reed B C,Brow n J F,et al,2000.Development of a global land cover characteristics database and IGBP DISCover from1-km AVHRR data.International Journal of Remote Sensing,21:1303-1330,DOI:10.1080/014311600210191.
Pathirana A,Denekew H B,Veerbeek W,et al,2014.Impact of urban grow th-driven landuse change on microclimate and extreme precipitation-A sensitivity study[J].Atmospheric Research,138(3):59-72.DOI:10.1016/j.atmosres.2013.10.005.
江志红,李杨,2014.中国东部不同区域城市化对降水变化影响的对比研究[J].热带气象学报,30(4):601-611.DOI:10.3969/j.issn.1004-4965.2014.04.001.
廖镜彪,王雪梅,李玉欣,等,2011.城市化对广州降水的影响分析[J].气象科学,31(4):384-390.
刘振鑫,2014.应用城市冠层模式与WRF模式耦合研究城市化效应[D].北京:北京大学.
蒙伟光,闫敬华,扈海波,2007.热带气旋背景条件下的城市效应与广州夏季雷暴[J].中国科学(地球科学),37(12):1660-1668.DOI:10.3321/j.issn:1006-9267.2007.12.012.
蒙伟光,张艳霞,李江南,等,2010.WRF/UCM在广州高温天气及城市热岛模拟研究中的应用[J].热带气象学报,26(3):273-282.DOI:10.3969/j.issn.1004-4965.2010.03.003.
寿亦萱,张大林,2012.城市热岛效应的研究进展与展望[J].气象学报,70(3):338-353.DOI:10.11676/qxxb2012.031.
覃月凤,顾建峰,吴钲,等,2015.雷达资料同化频次对一次西南涡暴雨的影响试验[J].高原气象,34(4):963-972.DOI:10.7522/j.issn.1000-0534.2014.00050.
吴风波,汤剑平,2011.城市化对2008年8月25日上海一次特大暴雨的影响[J].南京大学学报(自然科学版),47(1):71-81.
吴风波,汤剑平,2015.城市化对长江三角洲地区夏季降水、气温的影响[J].热带气象学报,31(2):255-263.DOI:10.16032/j.issn.1004-4965.2015.02.012.
王洪,王东海,万齐林,2015.多普勒雷达资料同化在“7·21”北京特大暴雨个例中的应用[J].气象学报,73(4):679-696.DOI:10.11676/qxxb2015.048.
王晖,隆霄,温晓培,等,2017.2012年宁夏“7·29”大暴雨过程的数值模拟研究[J].高原气象,36(1):268-281.DOI:10.7522/j.issn.1000-0534.2016.00017.
王楠,赵强,井宇,等,2018.秦岭北麓一次冷锋触发的短时强降水成因分析[J].高原气象,37(5):888-888.DOI:10.7522/j.issn.1000-0534.2017.00070.
王晓峰,王平,张蕾,等,2017.多源观测在快速更新同化系统中的敏感性试验[J].高原气象,36(1):148-161.DOI:10.7522/j.issn.1000-0534.2016.00018.
张珊,黄刚,王君,等,2015.城市地表特征对京津冀地区夏季降水的影响研究[J].大气科学,39(5):911-925.DOI:10.3878/j.issn.1006-9895.1411.14199.
Daniels E E,Hutjes R W A,Lenderink G,et al,2015.Land surface feedbacks on spring precipitation in the Netherlands[J].Journal of Hydrometeorology,16(1):232-243.DOI:10.1175/JHM-D-14-0072.1.
Lin C Y,Chen W C,Liu S C,et al,2008.Numerical study of the impact of urbanization on the precipitation over Taiw an[J].Atmospheric Environment,42(13):2934-2947.DOI:10.1016/j.atmosenv.2007.12.054.
Loveland T R,Reed B C,Brow n J F,et al,2000.Development of a global land cover characteristics database and IGBP DISCover from1-km AVHRR data.International Journal of Remote Sensing,21:1303-1330,DOI:10.1080/014311600210191.
Pathirana A,Denekew H B,Veerbeek W,et al,2014.Impact of urban grow th-driven landuse change on microclimate and extreme precipitation-A sensitivity study[J].Atmospheric Research,138(3):59-72.DOI:10.1016/j.atmosres.2013.10.005.
江志红,李杨,2014.中国东部不同区域城市化对降水变化影响的对比研究[J].热带气象学报,30(4):601-611.DOI:10.3969/j.issn.1004-4965.2014.04.001.
廖镜彪,王雪梅,李玉欣,等,2011.城市化对广州降水的影响分析[J].气象科学,31(4):384-390.
刘振鑫,2014.应用城市冠层模式与WRF模式耦合研究城市化效应[D].北京:北京大学.
蒙伟光,闫敬华,扈海波,2007.热带气旋背景条件下的城市效应与广州夏季雷暴[J].中国科学(地球科学),37(12):1660-1668.DOI:10.3321/j.issn:1006-9267.2007.12.012.
蒙伟光,张艳霞,李江南,等,2010.WRF/UCM在广州高温天气及城市热岛模拟研究中的应用[J].热带气象学报,26(3):273-282.DOI:10.3969/j.issn.1004-4965.2010.03.003.
寿亦萱,张大林,2012.城市热岛效应的研究进展与展望[J].气象学报,70(3):338-353.DOI:10.11676/qxxb2012.031.
覃月凤,顾建峰,吴钲,等,2015.雷达资料同化频次对一次西南涡暴雨的影响试验[J].高原气象,34(4):963-972.DOI:10.7522/j.issn.1000-0534.2014.00050.
吴风波,汤剑平,2011.城市化对2008年8月25日上海一次特大暴雨的影响[J].南京大学学报(自然科学版),47(1):71-81.
吴风波,汤剑平,2015.城市化对长江三角洲地区夏季降水、气温的影响[J].热带气象学报,31(2):255-263.DOI:10.16032/j.issn.1004-4965.2015.02.012.
王洪,王东海,万齐林,2015.多普勒雷达资料同化在“7·21”北京特大暴雨个例中的应用[J].气象学报,73(4):679-696.DOI:10.11676/qxxb2015.048.
王晖,隆霄,温晓培,等,2017.2012年宁夏“7·29”大暴雨过程的数值模拟研究[J].高原气象,36(1):268-281.DOI:10.7522/j.issn.1000-0534.2016.00017.
王楠,赵强,井宇,等,2018.秦岭北麓一次冷锋触发的短时强降水成因分析[J].高原气象,37(5):888-888.DOI:10.7522/j.issn.1000-0534.2017.00070.
王晓峰,王平,张蕾,等,2017.多源观测在快速更新同化系统中的敏感性试验[J].高原气象,36(1):148-161.DOI:10.7522/j.issn.1000-0534.2016.00018.
张珊,黄刚,王君,等,2015.城市地表特征对京津冀地区夏季降水的影响研究[J].大气科学,39(5):911-925.DOI:10.3878/j.issn.1006-9895.1411.14199.