北方农牧交错带中部区域气候变化特征   总被引：12，自引：0，他引：12  

范锦龙  张艳  李贵才 《气候变化研究进展》2007,3(2):91-094

分析北方农牧交错带中部区域1951-2005年温度、降水的变化特征,结果表明,研究区近55 a的气温和降水具有如下特征：1）增温明显,气温变率为0.4℃/10 a,不同季节增温幅度以冬、春、夏、秋依次递减;2）降水变化可分为3个阶段：20世纪50-60年代降水量呈减少趋势,70-80年代处于较平稳的过渡期,90年代以来降水量又呈现增加趋势。夏季降水与年降水变化趋势类似,秋季与冬季降水波动较小,基本保持平稳。研究区高温、干旱有所加强,暴雨、低温事件减少。  相似文献   

近千年全球温度变化研究的新进展   总被引：16，自引：0，他引：16  

王绍武  罗勇  闻新宇  董文杰 《气候变化研究进展》2007,3(1):14-019

结合国内外有关研究,综合评述了美国国家科学院国家研究理事会的报告 --"近两千年地面温度的重建"。重点介绍了气候变暖的新证据,3个特征时期即20世纪气候变暖、小冰期（LIA）、中世纪暖期（MWP）和近千年温度变化模拟的结果。  相似文献   

Relationship between the Asian-Pacific oscillation and the tropical cyclone frequency in the western North Pacific   总被引：12，自引：1，他引：11  

Zhou BoTao  Cui Xuan  Zhao Ping 《中国科学D辑(英文版)》2008,51(3):380-385

The relationship between the Asian-Pacific oscillation (APO) and the tropical cyclone frequency over the western North Pacific (WNP) in summer is preliminarily investigated through an analysis of ob- served data. The result has shown clearly that APO is significantly and positively correlated to the tropical cyclone frequency in the WNP. If APO is above (below) the normal in summer, more (less) tropical cyclones will tend to appear in the WNP. The present study also addresses the large-scale at- mospheric general circulation changes underlying the linkage between APO and the WNP tropical cy- clone frequency. It follows that a positive phase of summer APO is concurrent with weakened as well as northward and eastward located western Pacific subtropical high (WPSH), low-level convergence and high-level divergence, and reduced vertical zonal wind shear in the WNP, providing favorable envi- ronment for the tropical cyclone genesis, and thus more tropical cyclones will come into being, and vice versa.  相似文献   

1955-2002年气候因子对鄱阳湖流域径流系数的影响   总被引：2，自引：0，他引：2       下载免费PDF全文

郭华  姜彤  王艳君  陈桂亚 《气候变化研究进展》2006,2(5):217-222

1955-2002年间,鄱阳湖流域径流系数均呈现显著上升趋势,有较明显的突变性和阶段性,突变主要发生在20世纪60年代末和90年代初。径流系数的趋势及突变与该时期降水量的变化吻合较好;气温和蒸发量的变化趋势及突变点也与径流系数基本吻合;季节变化中,7-9月的径流系数与气候因子的变化趋势最为吻合。气候因子的变化与鄱阳湖流域径流系数变化的一致性,说明48 a来气候变化对径流系数的影响非常显著。尽管鄱阳湖流域的径流系数还受到土地利用变化、水土流失和地形等因素叠加效应的影响,但是气候变化仍然是其主要影响因素。  相似文献   

珠穆朗玛峰地区近34年来气候变化   总被引：34，自引：3，他引：31  

杨续超  张镱锂  张玮  阎宇平  王兆锋  丁明军  除多 《地理学报》2006,61(7):687-696

利用珠穆朗玛峰地区中国境内5个气象站1971~2004年月平均气温、月平均最高、最低气温、月降水资料,采用气候线性趋势分析、滑动平均、低通滤波、累积距平等方法对珠峰地区近34年气候变化的时空分布特征进行了分析。结果表明：(1) 1971~2004年珠峰地区气温呈现出明显的上升趋势,其中海拔最高的定日站增幅最高,且以冬半年非生长季气温增长更为显著;(2) 近34年珠峰地区的变暖要明显早于中国及全球,且升温幅度更大;(3) 珠峰南、北翼降水变化趋势明显不同,北翼4站降水以增加趋势为主,但是总体显著性水平不高,而珠峰南翼的聂拉木降水以减少趋势为主,从90年代初开始降水以较大幅度减少;(4) 与已有研究结果比较发现：珠峰高海拔地区是中国同期升温最显著的区域。设立在海拔5032 m珠峰大本营的世界上海拔最高的无人值守实时自动气象站将会在全球变化监测中发挥重要的作用。  相似文献   

Wisconsinan and Holocene Climate History from an Ice Core at Taylor Dome, Western Ross Embayment, Antarctica   总被引：4，自引：0，他引：4  

Eric J. Steig  David L. Morse  Edwin D. Waddington  Minze Stuiver  Pieter M. Grootes  Paul A. Mayewski  Mark S. Twickler  & Sallie I. Whitlow 《Geografiska Annaler: Series A, Physical Geography》2000,82(2-3):213-235

Geochemical data and geophysical measurements from a 554-m ice-core from Taylor Dome, East Antarctica, provide the basis for climate reconstruction in the western Ross Embayment through the entire Wisconsinan and Holocene. In comparison with ice cores from central East and West Antarctica, Taylor Dome shows greater variance of temperature, snow accumulation, and aerosol concentrations, reflecting significant variability in atmospheric circulation and air mass moisture content. Extreme aridity during the last glacial maximum at Taylor Dome reflects both colder temperatures and a shift in atmospheric circulation patterns associated with the advance of the Ross Sea ice sheet and accounts for regional alpine glacier retreats and high lake levels in the Dry Valleys. Inferred relationships between spatial accumulation gradients and ice sheet configuration indicate that advance of the Ross Sea ice sheet began in late marine isotope stage 5 or early stage 4. Precise dating of the Taylor Dome core achieved by trace-gas correlation with central Greenland ice cores shows that abrupt deglacial warming at Taylor Dome was near-synchronous with the ∼14.6 ka warming in central Greenland and lags the general warming trend in other Antarctic ice cores by at least 3000 years. Deglacial warming was following by a warm interval and transient cooling between 14.6 and 11.7 ka, synchronous with the Bølling/Allerød warming and Younger Dryas cooling events in central Greenland, and out of phase with the Antarctic Cold Reversal recorded in the Byrd (West Antarctica) ice core. Rapid climate changes during marine isotope stages 4 and 3 at Taylor Dome are similar in character to, and may be in phase with, the Northern Hemisphere stadial–interstadial (Dansgaard–Oeschger) events. Results from Taylor Dome illustrate the importance of obtaining ice cores from multiple Antarctic sites, to provide wide spatial coverage of past climate and ice dynamics.  相似文献   

Integrated geodynamical network in Russia. (Scientific objectives and realization)     

《Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy》2000,25(12):819-822

Determination of a geodetic reference frame and a unique system of normal heights, meeting requests of geodynamic studies, demands an accomplishment of a complex of different types of geodetic measurements (space and terrestrial), as each of techniques separately unable to give a singular interpretation. A problem of precise determination of the quasigeoid heights can be solved by joined analysis of GPS/GLONASS measurements and gravimetric data, if for the GPS sites precise levelling data are available. An establishment of the Fiducial Astro-Geodetic network (FAGN), based mainly on the use of space geodesy technique, is a principal objective of the national programme which is carried out in Russia, under the management of the Federal Department of Geodesy and Cartography and in collaboration with research institutes of the Russian Academy of Sciences. A real situation with the existing russian stations for geodynamical monitoring is considered, and a programme of upgrading of the integrated fundamental geodetic network is discussed.  相似文献   

Subtropical air-sea interaction and development of central Pacific El Niño     

XIE Ruihuang  HUANG Fei  REN Hongli 《中国海洋大学学报(英文版)》2013,12(2):260-271

The standard deviation of the central Pacific sea surface temperature anomaly (SSTA) during the period from October to February shows that the central Pacific SSTA variation is primarily due to the occurrence of the Central Pacific El Nio (CP-El Nio) and has a connection with the subtropical air-sea interaction in the northeastern Pacific. After removing the influence of the Eastern Pacific El Nio, an S-EOF analysis is conducted and the leading mode shows a clear seasonal SSTA evolving from the subtropical northeastern Pacific to the tropical central Pacific with a quasi-biennial period. The initial subtropical SSTA is generated by the wind speed decrease and surface heat flux increase due to a north Pacific anomalous cyclone. Such subtropical SSTA can further influence the establishment of the SSTA in the tropical central Pacific via the wind-evaporation-SST (WES) feedback. After established, the central equatorial Pacific SSTA can be strengthened by the zonal advective feedback and thermocline feedback, and develop into CP-El Nio. However, as the thermocline feedback increases the SSTA cooling after the mature phase, the heat flux loss and the re-versed zonal advective feedback can cause the phase transition of CP-El Nio. Along with the wind stress variability, the recharge (discharge) process occurs in the central (eastern) equatorial Pacific and such a process causes the phase consistency between the thermocline depth and SST anomalies, which presents a contrast to the original recharge/discharge theory.  相似文献   

辽宁地区夏季高温极值预测模型   总被引：1，自引：0，他引：1       下载免费PDF全文

李娇  任国玉  任玉玉  沈志超  孙秀宝 《气象与环境学报》2012,28(6):50-57

利用1957-2006年辽宁地区夏季23站极端最高气温资料和国家气候中心气候监测室的74项环流特征量资料,应用EOF方法对高温极值样本进行分解,研究辽宁极端高温的时空分布规律。结果表明：第一特征向量表现为区域整体一致的特征,中心区位于辽西北、辽北,第二、三特征向量空间分布表现为东西部反位相和南北反位相的特征。普查了前3个时间系数与前期环流指数的相关关系,认为前3个时间系数的显著影响因子是不同的。采用CSC准则确定最优预测因子,分别建立各时间系数的回归统计模型,并对高温极值历史拟合序列进行回报检验和预测检验。回报结果表明,各站的历史拟合率都保持在一定水平,但拟合率在辽西地区较差。各年的历史拟合率极不均衡,多数年份较为稳定,但个别年份拟合率较低。未来3 a试验性预测效果逐年下降,模型对未来1 a预测能力较好,可以作为业务预测的参考。  相似文献   

Spatial and temporal characteristics of actual evapotranspiration over Haihe River basin in China   总被引：1，自引：0，他引：1  

Ge Gao  Chong-Yu Xu  Deliang Chen  V. P. Singh 《Stochastic Environmental Research and Risk Assessment (SERRA)》2012,26(5):655-669

Spatial and temporal characteristics of actual evapotranspiration over the Haihe River basin in China during 1960–2002 are estimated using the complementary relationship and the Thornthwaite water balance (WB) approaches. Firstly, the long-term water balance equation is used to validate and select the most suitable long-term average annual actual evapotranspiration equations for nine subbasins. Then, the most suitable method, the Pike equation, is used to calibrate parameters of the complementary relationship models and the WB model at each station. The results show that the advection aridity (AA) model more closely estimates actual evapotranspiration than does the Granger and Gray (GG) model especially considering the annual and summer evapotranspiration when compared with the WB model estimates. The results from the AA model and the WB model are then used to analyze spatial and temporal changing characteristics of the actual evapotranspiration over the basin. The analysis shows that the annual actual evapotranspirations during 1960–2002 exhibit similar decreasing trends in most parts of the Haihe River basin for the AA and WB models. Decreasing trends in annual precipitation and potential evapotranspiration, which directly affect water supply and the energy available for actual evapotranspiration respectively, jointly lead to the decrease in actual evapotranspiration in the basin. A weakening of the water cycle seems to have appeared, and as a consequence, the water supply capacity has been on the decrease, aggravating water shortage and restricting sustainable social and economic development in the region.  相似文献