欧亚大陆桥(中国段)沿线气候特征与灾害区段划分研究     

余优森  陈榛妹  陈添宇 《气象学报》1998,56(2):178-186

分析研究了欧亚大陆桥（中国段）沿线的气候特征与地理环境,影响和阻碍铁路运输的气象灾害;作了气象灾害区段划分,并提出铁路安全运输的气象保障与服务。  相似文献   

大气低频遥相关及其水平传播机制的解析研究     

薛凡炳 《热带气象学报》1998,14(2):126-134

（１）利用大气对流层中部无辐散层的存在,垂直积分热力学方程,并对整个对流层的距平加热场作解析近似的描写,联立涡度方程,得到最非绝热地转的２５０ｈＰａ距平流函数方程。它的形式酷似正压涡度方程。（２）讨论了罗斯贝波列的谱平均相速和群速。证明了气候平均高度场的闭合中心,就是中高纬度大气低频振子。其两侧位相变化相反,它的能源主要来自ＣＩＳＫ凝结正反馈或海温的感热。（３）导出了低频相关射线公式,它表明低频射  相似文献   

Arctic sea ice and Eurasian climate: A review   总被引：12，自引：0，他引：12  

GAO Yongqi  SUN Jianqi  LI Fei  HE Shengping  Stein SANDVEN  YAN Qing  ZHANG Zhongshi  Katja LOHMANN  Noel KEENLYSIDE  Tore FUREVIK  SUO Lingling 《大气科学进展》2015,32(1):92-114

The Arctic plays a fundamental role in the climate system and has shown significant climate change in recent decades,including the Arctic warming and decline of Arctic sea-ice extent and thickness. In contrast to the Arctic warming and reduction of Arctic sea ice, Europe, East Asia and North America have experienced anomalously cold conditions, with record snowfall during recent years. In this paper, we review current understanding of the sea-ice impacts on the Eurasian climate.Paleo, observational and modelling studies are covered to summarize several major themes, including: the variability of Arctic sea ice and its controls; the likely causes and apparent impacts of the Arctic sea-ice decline during the satellite era,as well as past and projected future impacts and trends; the links and feedback mechanisms between the Arctic sea ice and the Arctic Oscillation/North Atlantic Oscillation, the recent Eurasian cooling, winter atmospheric circulation, summer precipitation in East Asia, spring snowfall over Eurasia, East Asian winter monsoon, and midlatitude extreme weather; and the remote climate response(e.g., atmospheric circulation, air temperature) to changes in Arctic sea ice. We conclude with a brief summary and suggestions for future research.  相似文献   

欧亚大陆春季融雪与长江流域夏季降水的可能联系   总被引：1，自引：1，他引：0  

韩冬  陈海山  许蓓  齐铎  吴波 《气象科学》2014,34(3):237-242

利用1979—2007年全球月平均的积雪水当量资料,定义了春季积雪水当量增量指数,该指数可以较为直观地反映春季融雪的情况。通过这一纽带,分析了欧亚大陆春季融雪与长江流域夏季降水之间的联系。研究表明:欧亚大陆春季融雪与中国长江流域夏季降水是负相关关系,这与高原积雪的影响是不一致的。春季融雪量的减少,使得欧亚大陆北部夏季剩余积雪偏多,夏季融雪增多。融雪的局地效应使得土壤湿度增加,加大了欧亚大陆南北热力差异。从而,夏季中纬度的纬向风切变增大,对流层上层的副热带西风急流增强,副热带高压增强西伸,但是北抬受到抑制。长江流域位于异常西南暖湿气流与冷空气的辐合带上,上升运动活跃,有利于降水偏多。  相似文献   

两类La Nia季节演变过程的海气耦合特征对比   总被引：5，自引：4，他引：1  

王磊  张文君  祁莉  何金海 《海洋学报》2014,36(1):72-85

利用1951—2010年逐月的HadISST海表温度资料、SODA次表层海温资料和NCEP/NCAR再分析资料等,对比分析了东太平洋(EP型)La Nia和中太平洋(CP型)La Nia的海气耦合特征在季节演变过程中的差异。EP La Nia海表温度异常中心在发展年夏季出现于南美沿岸,随后向西移动,盛期最大海表温度异常中心位于赤道东太平洋,而CP La Nia海温异常中心少动,基本维持在160°W附近,其强度更强,持续时间更长。受海温分布形态影响,热带大气对两类La Nia的响应非常不同,成熟期间CP型在中太平洋偏旱的强度和范围比EP型大,且略偏西。发展年夏、秋季,北半球位势高度响应较弱;冬季,负PNA位相易伴随两类La Nia出现,但异常活动中心的位置和强度不同,在北大西洋其大气响应几乎相反,这些差异会引起显著不同的区域气候异常。  相似文献   

Lake Ladoga ice phenology: Mean condition and extremes during the last 65 years     

Sergey Karetnikov  Mikhail Naumenko 《水文研究》2011,25(18):2859-2867

Winter conditions play an important role for the largest lake in Europe—Lake Ladoga. The ice cover lasts for 171 ± 3 days on average from the early November until the mid‐May. We investigated the ice regime of Lake Ladoga using a constructed ice database of aircraft surveys and satellite images. More than 1250 surveys of the lake's ice cover from 1943 to 2010 were collected and analysed to determine mean and extreme ice conditions for winters of different types of severity. The time series of ice cover percentage over the lake was plotted. On average, 18 observational ice charts were made every winter. Individual ice phenology records show considerable year‐to‐year variation. For this reason, records typically have been combined and analysed as groups (categories). Extremely cold winters were determined as winters with complete ice cover that lasts more than three months which is approximately 90% quartiles from all winters with complete ice cover. The lake surface was completely covered with ice for more than three months during 5 seasons. Extremely warm winters when the maximum ice cover was less than 70% of the lake area occurred during 5 seasons as well. A basic relationship between the winter severity as winter maximum of accumulated freezing degree‐days (AFDD) and the earlier derived Relative Ice Cover Index (RICI) was established. We have used teleconnection indices such as North Atlantic Oscillations (NAO) and Arctic Oscillation (AO) for the period from October to May for estimation of different types of Lake Ladoga's ice conditions. The AO index in winter months and local winter maximum of AFDD explained much of the interannual variation in ice cover. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

PRECIPITATION PATTERNS IN FLOOD SEASON OVER CHINA ASSOCIATED WITH THE EL NI■O/SOUTHERN OSCILIATION     

钱步东 《中国地理科学(英文版)》1997,(3)

I.I~IOXENds(EINabs/SouthernOscillation)eventsaretheintensivesignalsofair-seainteractionintropicalarea.PlentyOfresultsfromdifferentresearchersshoWthattheENdssignalcanbedetectedoninterannualvallationsoflargescaleatmOSPhericcirculationandclimateregimeSovermostpartsoftheworld.SeveralkindsofrelationShipbetweenENdsandprecipitationoverChinahavebeenrevealedbydifferentreSearcherS,buttherearemanydifferencesamongthepublishedreSults.Itmayberesulted*fromthatdifferentreSearchersuseddifferentindic…  相似文献   

Association of Indian Ocean ITCZ Variations with the Arctic Oscillation during Boreal Winter          下载免费PDF全文

GONG Dao-Yi  GAO Yong-Qi  HU Miao  GUO Dong 《大气和海洋科学快报》2013,6(5):300-305

In this study,the authors analyzed the associations between the Arctic Oscillation(AO)and the tropical Indian Ocean(TIO)intertropical convergence zone(ITCZ)in boreal winter for the period 1979–2009.A statistically significant AO-TIO ITCZ linkage was found.The ITCZ vertical air motion is significantly associated with the AO,with upward(downward)air motion corresponding to the positive(negative)AO phase.The Arabian Sea anticyclone plays a crucial role in linking the AO and the TIO ITCZ.The Arabian Sea vorticity is strongly linked to high-latitude disturbances in conjunction with jet stream waveguide effects of disturbance trapping and energy dispersion.During positive(negative)AO years,the Arabian Sea anticyclone tends to be stronger(weaker).The mean vorticity over the Arabian Sea,averaged from 850hPa to 200 hPa,has a significant negative correlation with AO(r=0.63).The anomalous anticyclone over the Arabian Sea brings stronger northeastern winds,which enhance the ITCZ after crossing the equator and result in greater-than-normal precipitation and minimum outgoing long-wave radiation.  相似文献   

Long-period variations of sea-level in Australasia     

J. I. Pariwono  J. A. T. Bye  G. W. Lennon 《Geophysical Journal International》1986,87(1):43-54

Summary. The ability of the Australian sea-level monitoring network is assessed in the investigation of long-period sea-level signals. Through the character of coastal long waves, seasonal variations in level and inter-annual level anomalies, the importance of the south coast of the Continent is identified as a coherent indicator of large-scale marine and atmospheric teleconnections. The source of the sea-level signal is investigated by the tracing of progressive features, by the numerical modelling of wind stress over the Southern Ocean, by the modelling of the effect of monsoonal rains over the Indian Ocean and the mass transport through the Indonesian Strait. These features are related to the ENSO cycle which for the first time is linked, inter alia , with Southern Ocean mechanisms.  相似文献   

Frequency dependence of Q in the mantle underlying the shield areas of Eurasia, Part III: The Q model   总被引：2，自引：0，他引：2  

Zoltan A. Der  Alison C. Lees  Vernon F. Cormier 《Geophysical Journal International》1986,87(3):1103-1112

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