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本文利用NCEP/NCAR逐日再分析资料中的气温、2 m气温(T2m)、位势高度、降水、水平风和垂直速度，探讨了影响北美西北部长持续性和短时冷事件的特征，分析了与长持续性冷事件发生、发展相关的遥相关机制。基于1982—2023年期间的历史观测数据，本文依据冷事件累积2 m高度温度异常，筛选出65次冷事件，根据持续时间的概率密度函数，将冷事件划分为57次短时冷事件和8次长持续性冷事件。结果表明，由于持续时间的差异，长持续性冷事件的累积2 m温度异常显著低于短时冷事件。两类冷事件对应的大气环流异常形势均表现出北美西北部低压异常与其西侧高压异常构成的正压偶极子特征，长持续性冷事件的低压系统持续时间更长。在半球尺度上，该偶极子结构属于罗斯贝波列的一部分。地中海北部、日本南部和热带西太平洋附近的非绝热加热异常是该波列的重要触发因素，对长持续性冷事件上空低压异常的产生和维持起到关键作用。遥相关波列在北美西北部冬季长持续性冷事件中的重要影响可为该地区冬季长持续性冷事件的预报提供一定的科学参考。
Abstract：This study investigates the characteristics of long-lived and short-lived cold events in Wes-tern North America using daily NCEP/NCAR reanalysis data, including surface air temperature, temperature at 2-meter(T2m), geopotential height, precipitation, horizontal winds, and vertical velocity. The teleconnection mechanisms associated with the initiation and development of long-lived cold events are systematically analyzed. Based on historical observations from 1982 to 2023, 65 cold events were identified through cumulative T2m anomalies, with 57 classified as short-lived events and 8 as long-lived events according to the probability density function of their durations. The results demonstrate that prolonged cold events exhibit significantly stronger cumulative T2m anomalies compared to short-lived counterparts. Both cold event categories exhibit barotropic dipole anomalies in atmospheric circulation patterns, characterized by low-pressure anomalies over Western North America coupled with adjacent high-pressure anomalies to the west, though the low-pressure systems persist for longer durations during long-livee events. Hemispheric-scale analysis reveals this dipole structure as part of a Rossby wave train. Diabatic heating anomalies over the North Mediterranean, South Japan, and tropical Western Pacific serve as crucial triggers for this wave train, playing a pivotal role in generating and maintaining the low-pressure anomalies over long-lived cold events. The identified teleconnection impacts of Rossby wave trains on wintertime long-lived cold events provide valuable scientific references for improving extended-range cold weather forecasting in this region.
[1] Smith E T,Sheridan S C.The influence of extreme cold events on mortality in the United States[J].Science of the Total Environment,2019,647:342-351.
[2] Kim Y,Lee S.Trends of extreme cold events in the central regions of Korea and their influence on the heating energy demand[J].Weather and Climate Extremes,2019,24:100199.
[3] Grotjahn R,Black R,Leung R,et al.North American extreme temperature events and related large scale meteorological patterns:A review of statistical methods,dynamics,modeling,and trends[J].Climate Dynamics,2016,46:1151-1184.
[4] Yamaguchi J,Kanno Y,Chen G,et al.Cold air mass analysis of the record-breaking cold surge event over East Asia in January 2016[J].Journal of the Meteorological Society of Japan,2019,97(1):275-293.
[5] Ma S,Zhu C.Extreme cold wave over East Asia in January 2016:A possible response to the larger internal atmospheric variability induced by Arctic warming[J].Journal of Climate,2019,32(4):1203-1216.
[6] Zhou C,Dai A,Wang J,et al.Quantifying human-induced dynamic and thermodynamic contributions to severe cold outbreaks like November 2019 in the eastern United States[J].Bulletin of the American Meteorological Society,2021,102(1):17-24.
[7] Andrew Weber.Texas Winter Storm Death Toll Goes up to 210,Including 43 Deaths In Harris County [PP/OL].(2021-07-14) [2025-02-27].https://www.houstonpublicmedia.org/articles/news/energy-environment/2021/07/14/403191/texas-winter-storm-death-toll-goes-up-to-210-including-43-deaths-in-harris-county/.
[8] Zishka K M,Smith P J.The climatology of cyclones and anticyclones over North America and surrounding ocean environs for January and July,1950—1977[J].Monthly Weather Review,1980,108(4):387-401.
[9] Turner J K,Gyakum J R.The development of Arctic air masses in Northwest Canada and their behavior in a warming climate[J].Journal of Climate,2011,24(17):4618-4633.
[10] Lin H,Brunet G,Derome J.An observed connection between the North Atlantic oscillation and the Madden-Julian oscillation[J].Journal of Climate,2009,22(2):364-380.
[11] Gong H,Ma K,Wang L.Internal variability dominated the extreme cold wave over North America in December 2022[J].Geophysical Research Letters,2024,51(18):e2024GL111429.
[12] Shi J,Wu K,Qian W,et al.Characteristics,trend,and precursors of extreme cold events in northwestern North America[J].Atmospheric Research,2021,249:105338.
[13] Hou Y,Johnson N C,Chang C H,et al.Cold springs over Mid-Latitude North America induced by tropical atlantic warming[J].Geophysical Research Letters,2023,50(16):e2023GL104180.
[14] Ogi M,Rysgaard S,Barber D.Cold winter over North America:The influence of the East Atlantic (EA) and the tropical/Northern Hemisphere (TNH) teleconnection patterns[J].The Open Atmospheric Science Journal,2016,10:6-13.
[15] Baxter S,Nigam S.Key role of the North Pacific oscillation-west Pacific pattern in generating the extreme 2013/14 North American winter[J].Journal of Climate,2015,28(20):8109-8117.
[16] Zhang Y,Shi J,Chen Y,et al.Intraseasonal relationship of winter temperatures in North America and warm sea surface temperatures in the Northeast Pacific[J].Atmospheric Research,2025,313:107773.
[17] Kug J S,Jeong J H,Jang Y S,et al.Two distinct influences of Arctic warming on cold winters over North America and East Asia[J].Nature Geoscience,2015,8(10):759-762.
[18] Zhang X,Fu Y,Han Z,et al.Extreme cold events from East Asia to North America in winter 2020/21:Comparisons,causes,and future implications[J].Advances in Atmospheric Sciences,2022,39:553-565.
[19] Yao Y,Zhuo W,Gong Z,et al.Extreme cold events in North America and Eurasia in November-December 2022:A potential vorticity gradient perspective[J].Advances in Atmospheric Sciences,2023,40:953-962.
[20] Zhang R,Screen J A,Zhang R.Arctic and Pacific Ocean conditions were favorable for cold extremes over Eurasia and North America during winter 2020/21[J].Bulletin of the American Meteorological Society,2022,103(10):2285-2301.
[21] Doss-Gollin J,Farnham D J,Lall U,et al.How unprecedented was the February 2021 Texas cold snap?[J].Environmental Research Letters,2021,16(6):064056.
[22] Zhang Y X,Liu Y J,Ding,Y H.Identification of winter long-lasting regional extreme low-temperature events in Eurasia and their variation during 1948—2017[J].Advances in Climate Change Research,2021,12(3):353-362.
[23] Leetmaa A,Reynolds R,Jenne R,et al.The NCEP/NCAR 40-year reanalysis project[J].Bulletin of the American Meteorological Society,1996,77:437-471.
[24] Hersbach H,Bell B,Berrisford P,et al.The ERA5 global reanalysis[J].Quarterly Journal of the Royal Meteorological Society,2020,146(730):1999-2049.
[25] Peng J B,Cholaw B.The definition and classification of extensive and persistent extreme cold events in China[J].Atmospheric and Oceanic Science Letters,2011,4(5):281-286.
[26] Fu D,Ding Y.The study of changing characteristics of the winter temperature and extreme cold events in China over the past six decades[J].International Journal of Climatology,2021,41(4):2480-2494.
[27] Ji L,Chen H.Differences in variations of long-lived and short-lived summer heat waves during 1981—2020 over eastern China and their corresponding large-scale circulation anomalies[J].Journal of Meteorological Research,2024,38(3):414-436.
[28] Takaya K,Nakamura H.A formulation of a phase-independent wave-activity flux for stationary and migratory quasigeostrophic eddies on a zonally varying basic flow[J].Journal of the Atmospheric Sciences,2001,58(6):608-627.
[29] Sardeshmukh P D,Hoskins B J.The generation of global rotational flow by steady idealized tropical divergence[J].Journal of Atmospheric Sciences,1988,45(7):1228-1251.
[30] Yanai M,Esbensen S,Chu J H.Determination of bulk properties of tropical cloud clusters from large-scale heat and moisture budgets[J].Journal of Atmospheric Sciences,1973,30(4):611-627.
[31] Watanabe M,Kimoto M.Atmosphere-ocean thermal coupling in the North Atlantic:A positive feedback[J].Quarterly Journal of the Royal Meteorological Society,2000,126(570):3343-3369.
[32] Kanamitsu M,Ebisuzaki W,Woollen J,et al.NCEP-DOE AMIP-Ⅱ reanalysis (r-2)[J].Bulletin of the American Meteorological Society,2002,83(11):1631-1644.
[33] An X,Chen W,Fu S,et al.Possible dynamic mechanisms of high-and low-latitude wave trains over Eurasia and their impacts on air pollution over the North China Plain in early winter[J].Journal of Geophysical Research:Atmospheres,2022,127(13):e2022JD036732.
[34] Chen J,Li R,Mao J,et al.Different modulations of Arctic Oscillation on wintertime sea surface temperature anomalies in the Northeast Pacific[J].Journal of Geophysical Research:Atmospheres,2024,129(19):e2024JD041360.
[35] Branstator G.Circumglobal teleconnections,the jet stream waveguide,and the North Atlantic Oscillation[J].Journal of Climate,2002,15(14):1893-1910.
[36] Qin J,Robinson W A.On the Rossby wave source and the steady linear response to tropical forcing[J].Journal of Atmospheric Sciences,1993,50(12):1819-1823.
[37] Shi J,Huang H,Fedorov A V,et al.Northeast Pacific warm blobs sustained via extratropical atmospheric teleconnections[J].Nature Communications,2024,15(1):2832.
基本信息:
DOI：10.16441/j.cnki.hdxb.20250067
中图分类号:P467
引用信息:
[1]强倩,陈嘉杰,石剑.冬季北美西北部长短冷事件的特征与物理机制[J].中国海洋大学学报(自然科学版),2026,56(01):1-14.DOI:10.16441/j.cnki.hdxb.20250067.
基金信息:
国家自然科学基金项目(42430411)资助~~