THE RELATIONSHIP BETWEEN AMPLIFICATION OF THE SUBTROPICAL STATIONARY WAVES IN THE BOREAL SUMMER AND THE ASSOCIATION WITH PRECIPITATION EXTREMES OVER CHINA
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摘要: 围绕夏季副热带行星波动的振幅异常，分析其与我国极端降水的关系，并探讨可能的影响机制。结果表明，北半球夏季行星波振幅强、弱年的差异主要表现在北太平洋副高和北大西洋副高的增强，并伴随着欧亚大陆的低压加深，即表现为海陆热力差异的增加和东亚夏季风环流的加强。在振幅强年，极端降水强度在我国北部明显加强，极端降水雨带异常偏北，而我国长江中下游流域极端降水则减弱，弱年则相反。伴随着增强的季风环流，在振幅强年水汽输送到达我国北部明显增强。同时，在大气低层我国绝大部分地区对流不稳定加剧；而在对流层中高层，我国北方地区斜压不稳定加剧，这都有利于振幅强年我国偏北部地区的极端降水偏强Abstract: Focused on the amplification of the subtropical stationary waves in the boreal summer, this study investigates its relationship with the precipitation extremes over China and its possible mechanism. The stationary waves amplification in boreal summer strengthens the subtropical high over the North Pacific and the North Atlantic and deepens the low-pressure system over Eurasia. Consequently, the east-west land-sea thermal contrast over China increases and the monsoon circulation strengthens. Amplified stationary waves are likely to contribute to the magnitude of precipitation extremes over the northern part of China, while decreasing that over the middle and lower reaches of Yangtze River. Associated with the strengthened East Asian summer monsoon, the moisture flux significantly increases over eastern China in the years of amplified stationary waves. Meanwhile, both of the convective and baroclinic instabilities are intensified over northern China. All these may trigger the precipitation extremes over northern China
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图 1 1961—2014年夏季925 hPa(a、c)和300 hPa(b、d)的涡动流函数(单位：106 m2/s)的气候平均态(a、b)和标准化行星波振幅指数SWI序列(c、d，红色实线分别对应±1)
图 11 1 000~700 hPa水汽通量(矢量，单位：g/(hPa·cm·s))及水汽通量散度(阴影，单位：g/(hPa·cm2·s))在行星波振幅
强弱年的差异黑点表示通过0.10的显著性检验的区域。
图 13 对流稳定度(a~b，单位：10-5 K/Pa)和斜压稳定度(c~d，单位：10-5 m/(s·Pa))在SWI强、弱年的差异
a、c为100~122 °E平均的纬度-高度剖面；b为700 hPa对流稳定度差异，d为500 hPa斜压稳定度差异；c、d中的黑点表示通过0.10的显著性检验的区域。
图 14 1961—2014年夏季6月(a~b)、7月(c~d)和8月(e~f)SWI指数强年(左)和弱年(右)的涡动流函数异常
单位：105 m2/s。黑点表示异常通过0.10的显著性检验的区域。
表 1 极端降水指数的定义
代码 名称 定义 单位 R1xDay 一日最大降水量 每月最大日降水量 mm/d CWD 最大持续湿期 日降水量持续≥1 mm的最长时期 d CDD 最大持续干期 日降水量持续 < 1 mm的最长时期 d R99p 一级极端降水强度 日降水量≥当月平均降水99%分位数的降水强度 mm/d R95p 二级极端降水强度 日降水量介于当月平均降水95%~99%分位数的降水强度 mm/d 
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[1] COUMOU D, RAHMSTORF S. A decade of weather extremes[J]. Nature Clim Change, 2012, 2(7): 491-496. [2] FRICH P, ALEXANDERL V, DELLA-MARTAP, et al. Observed coherent changes in climatic extremes during the second half of the twentieth century[J]. Clim Res, 2002, 19(3): 193-212, doi:10.3354/cr019193. [3] HUBERD G, GULLEDGEJ. Extreme weather and climate change, understanding the link, managing the risk[J]. Center Clim Energy Solut, 2011, 16(6):50-50. [4] 翟盘茂, 王萃萃, 李威.极端降水事件变化的观测研究[J].气候变化研究进展, 2007, 3(3): 144-148. [5] 王苗, 郭品文, 邬昀, 等.我国极端降水事件研究进展[J].气象科技, 2012, 40(1): 79-86. [6] 杨金虎, 江志红, 白虎志.西北区东部夏季极端降水事件同太平洋SSTA的遥相关[J].高原气象, 2008, 27(2): 331-338. [7] TANG Q, ZHANG XJ, FRANCIS JA. Extreme summer weather in northern mid-latitudes linked to a vanishing cryosphere. Nature Climate Change[J]. 2013, 4(1):45-50. [8] 邹燕, 何金海, 邱章如, 等.副高及其南侧偏东气流输送在福建前汛期降水中的作用[J].热带气象学报, 2006, 22(5):515-520. [9] 孙凤华, 张耀存, 郭兰丽.中国东部夏季降水与同期东亚副热带急流位置年代际异常的关系[J].高原气象, 2009, 28(6): 1 309-1 315. [10] 张永领, 丁裕国.我国东部夏季极端降水与北太平洋海温的遥相关研究[J].南京气象学报, 2004, 27(2): 244-252. [11] 黄荣辉, 蔡榕硕, 陈际龙, 等.我国旱涝气候灾害的年代际变化及其与东亚气候系统变化的关系[J].大气科学, 2006, 30(5): 730-743. [12] NIGAMS, DEWEAVERE. Stationary waves (orographic and thermally forced)[J]. Encyclop Atmos Scie, 2015, 38(1): 431-445. [13] CHENG, LUJ, BURROWSDA, et al. Local finite-amplitude wave activity as an objective diagnostic of midlatitude extreme weather[J]. Geophys Res Lett, 2015, 42(24), DOI: 10.1002/2015GL066959. [14] 陈文, 杨蕾, 黄荣辉. 北半球冬季准定常行星波活动的年际变化及其与北极涛动和ENSO的关系[C]//中国气象学会年会论文集. 北京: 中国气象学会, 2004. [15] 陈文, 康丽华.北极涛动与东亚冬季气候在年际尺度上的联系:准定常行星波的作用[J].大气科学, 2006, 30(5): 863-870. [16] 赵进平, 史久新, 王召民, 等.北极海冰减退引起的北极放大机理与全球气候效应[J].地球科学进展, 2015, 30(9): 985-995. [17] FRANCIS J A, VAVRUSS J. Evidence linking Arctic amplification to extreme weather in mid-latitudes[J]. Geophys Res Lett, 2012, 39(6), doi:10.1029/2012GL051000. [18] CHEN G, LU J, BURROWS D A, et al. Local finite-amplitude wave activity as an objective diagnostic of midlatitude extreme weather[J].Geophys Res Lett, 2015, doi:10.1002/2015GL066959. [19] SCREEN J A, SIMMONDSI. Exploring links between Arctic amplification and mid-latitude weather[J], Geophys Res Lett, 2013, 40: 959-964, doi:10.1002/GRL.50174. [20] PETOUKHOVV, RAHMSTORFS, PETRIS, SCHELLNHUBERH J. Quasiresonant amplification of planetary waves and recent Northern Hemisphere weather extremes[J]. Proc Natl Acad Sci USA, 2013, 110(14): 5 336-5 341. [21] BARNES E A. Revisiting the evidence linking Arctic amplification to extreme weather in midlatitudes[J]. Geophys Res Lett, 2013, 40(1): 1-6. [22] SCREENJ A, SIMMONDS I. Amplified mid-latitude planetary waves favor particular regional weather extremes[J].Nature Clim Change, 2014, 4(8):704-709. [23] 王苗, 郭品文, 邬昀.中国东部极端降水变化特征及其与大气稳定度的关系[J].大气科学学报, 2014, 37(1): 47-56. [24] KALNAY E. The NCEP/NCAR 40-year reanalysis project[J]. Bull Am Meteorol Soc, 1996, 77(3): 437-471. [25] 吴佳, 高学杰.一套格点化的中国区域逐日观测资料及与其它资料的对比[J].地球物理学报, 2013, 56(4): 1 102-1 111. [26] YUAN J, LIW, DENGY. Amplified subtropical stationary waves in boreal summer and their implications for regional water extremes[J].Environ Res Lett, 2015, 10, 104009, doi:10.1088/1748-9326/10/10/104009. [27] LINDZEN R S, FANELL B. A simple approximate result for maximum growth rate of baroclinic instabilities[J]. J Atmos Sci, 1980, 37(7): 1 648-1 654. [28] KYSELY J, BEGUERíA S, BERANOVá R, et al. Different patterns of climate change scenarios for short-term and multi-day precipitation extremes in the Mediterranean[J]. Glob Planet Change, 2012, s98-99(6): 63-72, doi:10.1016/j.gloplacha.2012.06.010. [29] CHEN Y, ZHAI P M. Synoptic-scale precursors of East Asia/Pacific teleconnection pattern responsible for persistent extreme precipitation in the Yangtze River Valley[J]. Q J R Meteorol Soc, 2015, 141(689): 1 389-1 403, doi:10.1002/qj.2448. [30] ZHOU T J, YU R C, Atmospheric water vapor transport associated with typical anomalous summer rainfall patterns in China[J]. J Geophys Res, 2005, 110(8): 211, D08104, doi:10.1029/2004JD005413. [31] FENG L. ZHOU T. Water vapor transport for summer precipitation over the Tibetan Plateau: Multi-dataset analysis[J]. J Geophys Res Atmos, 2012, 117(D20):20114, doi:10.1029/2011JD017012. [32] 伍荣生.现代天气学原理[M].北京:高等教育出版社, 2013: 268. [33] 李崇银.大气运动的一些基本动力过程的研究[J].气象科技, 1983(3): 31-37. -
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