内蒙古额济纳旗地貌特征及其构造、气候事件   总被引：3，自引：0，他引：3  

迟振卿  王永  姚培毅  闵隆瑞  刘训 《地质论评》2006,52(3):370-378

根据遥感卫星影像解译及野外地质实地调查,将内蒙古额济纳旗地区的地貌单元划分为中低山区、冲—洪积平原、湖积盆地及风成地貌。根据不同地貌单元组成的沉积物年龄测定和分析,初步认为上新世—早更新世的构造抬升形成苏泊淖尔级湖积阶地;早更新世末(750±60kaBP),发生一次明显的构造抬升活动,形成东、西居延海间的台地;另一次明显的构造抬升记录发生在中更世末—晚更新世初,即149±60kaBP之后,形成黑城冲湖积台地;苏泊淖尔级阶地形成于全新世早、中期,属气候干旱湖泊萎缩形成的气候阶地,阶地沉积物中保存的古风成砂丘,表明晚更新世末—全新世早期气候一度恶化。天鹅湖湖积阶地的形成表明5000a之后一段时间,气候相对适宜;全新世中后期,气候波动强烈,1200aBP出现一次丰水期。  相似文献   

甘南高原雷暴的气候特征   总被引：2，自引：0，他引：2  

王建兵 《干旱气象》2007,25(4):51-55

利用甘南州8个气象站自建站到2005年的雷暴资料,对雷暴的时空分布特征进行了分析,发现甘南州雷暴多发区位于西南部的玛曲、碌曲到东北部的合作之间;从年际变化看,大部分地方的年雷暴天数呈明显下降趋势,特别是1990年代中期后,这种下降趋势更明显,但各地雷暴初终间日数的变化并不明显;夏季雷暴天气出现最多,出现最多的月份是7月,雷暴次数约占全年雷暴次数的20.2%。春末夏初5月下旬到6月上旬、6月下旬和7月中下旬、8月下旬是各月的雷暴高发时段;甘南雷暴1天中的盛发期在12～20时,14～15时是雷暴出现的峰值时段。  相似文献   

Climatic change during the last 4000 years in the southern Tarim Basin,Xinjiang, northwest China   总被引：1，自引：0，他引：1  

Wei Zhong  Ji Bin Xue  Qiang Shu  Li Guo Wang 《第四纪科学杂志》2007,22(7):659-665

In this study, a ca. 4000 cal. yr ancient lacustrine (or wetland) sediment record at the southern margin of Tarim Basin is used to reconstruct the history of climate change. Six radiocarbon dates on organic matter were obtained. δ¹⁸O and δ¹³C of carbonate, pollen and sediment particle size were analysed for climate proxies. The proxies indicate that a drier climate prevailed in the area before ca. 1010 BC and during period 1010 BC–AD 500 climate then changed rapidly and continuously from dry to moist, but after about AD 500 climate generally shows dry condition. Several centennial‐scale climatic events were revealed, with the wettest spell during AD 450–550, and a relatively wetter interval between AD 930–1030. Pollen results show that regional climate may influence human agricultural activities. Spectral analysis of mean grain size (MGS) proxy reveals statistically pronounced cyclic signals, such as ca. 200 yr, ca. 120 yr, ca. 90 yr, ca. 45 yr and ca. 33 or 30 yr, which may be associated with solar activities, implying that solar variability plays an important role in the decadal‐ and centennial‐scale climate variations in the study area. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

东北地区以泥炭为信息载体的全新世气候变迁研究进展   总被引：1，自引：0，他引：1  

张新荣  胡克  胡一帆  介冬梅  王东坡 《华北地质》2007,30(1):39-45

泥炭作为一种地质信息载体,在全球环境变化研究中起着越来越重要的作用。我国东北地区地处全球变化的敏感区,泥炭地研究的意义更为显著。笔者针对近年来东北地区泥炭地研究的多种成果,对该区全新世以来泥炭沉积和区域气候变迁历史进行了系统分析。得出:①东北地区泥炭有三次沉积高峰,分别始于早全新世、中全新世与晚全新世初期;②该区10000a以来大体上经历了冷湿-温暖适宜-凉湿-温暖偏干-冷干-寒冷略湿-变暖这样一个气候变迁过程。  相似文献   

东营凹陷牛庄地区沙三段层序地层分析     

WANG Wei-qing ))  LIU Ning )  TIAN Fang ) ) Guangzhou Institute of Geochemistry  Chinese Academy of Sciences  Guangzhou    ) Geological Scientific Research Institute of Shengli Oilfield Company  SINOPEC  Dongying 《地层学杂志》2007,(Z2)

山东济阳坳陷东营凹陷牛庄地区沙三段层序地层分析是在三级层序划分的基础上,通过对沉积体系发育特征和气候旋回单元的识别和解剖,建立了高精度层序地层单元的基本构型。气候旋回包含了从干旱枯水期到潮湿湖泛期的完整过程,沉积响应为受湖平面变化、沉积物供给等因素控制的多种方式叠置的湖底扇和前积体等,多期气候旋回叠合构成了湖泊层序的基本面貌。通过气候旋回的识别,可以对不同级别层序间的包含关系,以及高精度层序的内部构成进行分析和讨论。  相似文献   

新疆乌兰乌苏物候变化规律及其对气候变化的响应   总被引：1，自引：0，他引：1  

徐腊梅  张明  晋绿生  杨景辉 《沙漠与绿洲气象(新疆气象)》2007,1(6):38-42

分析新疆乌兰乌苏农业气象试验站1980—2002年物候与相应气候因子资料,得出乌兰乌苏23a来气温增高,降水增多,气候增暖增湿;候鸟停留时间增长,与积温、日照时数和降水量的年变化趋势一致,除降水外,其他均存在显著正相关关系;木本植物生育期延长,与4—10月平均气温、平均相对湿度、总日照时数和总降水量趋势一致;初霜和终霜均推迟,无霜期缩短;初雪和初次积雪提前,终雪推迟,冬季雪日增长;积雪开始融化提前,完全融化推迟,融化时间增长;土壤表面开始解冻日期趋势提前,而土壤表面开始冻结日期趋势推迟。另外,通过物候与气象因子建立的最优回归方程,获得物候对气候响应的定量关系,为生态环境研究提供一定的理论依据。  相似文献   

梧州市种植桉树速生丰产林的气候条件分析     

徐芳卢雪香  李莲英 《广西气象》2007,28(3):43-46

从气象的角度,详细对比分析桉树人工林原产地与梧州市（含各县）气候条件的异同,找出它们的相似点,得出梧州市（含各县）的气候条件适宜推广种植桉树人工林的结论,并提出生产上的趋利避害措施和建议。  相似文献   

节气气候变化与上消化道出血的关系研究     

吴荣娟  邱赠东林平 《广西气象》2007,28(3):47-49

通过对2000-2005年龙岩市第一医院上消化道出血（UGB）患者入院时的节气归属及当时气象资料的收集,分析不同节气气候变化与UGB的关系,运用最优子集回归方法建立关系模式进行综合分析,得出影响上消化道出血发病趋势的关键气象要素是节气最高气温、最低气温、平均水汽压;通过节气气候因素对UGB影响的认识,提出相应的预防保健措施。  相似文献   

海南省澄迈县雷暴气候特征及其灾害防御   总被引：2，自引：0，他引：2  

黄明旺许向春  赵学华陈长丘 《广西气象》2007,28(3):50-52,46

通过统计分析海南省澄迈县1959-2004年逐日雷暴资料,找出雷暴发生时空分布特征,统计1995-2004年10a雷暴发生的影响天气系统,计算出各天气系统影响下雷暴发生的概率。分析结果表明：澄迈县雷暴日46a平均雷暴频次437次,年际变化呈波动减少趋势,5-8月是雷暴发生的高发期,占全年雷暴的53%,16-17时是一天中发生雷暴的最高期,西南方向发生的雷暴略多于其他方向,澄迈县受西南低压槽、南海低压槽和副热带高压等天气系统影响时发生雷暴的概率较大。  相似文献   

Testing the Ability of Numerical Model to Simulate Climate and Its Change With 4D-EOF Analysis     

ZHAO Deming  SU Bingkai  TANG Jianping 《Acta Meteorologica Sinica》2007,21(2):179-191

The four-dimensional empirical orthogonal function (4D-EOF), which in reality is a simple combination of three-dimensional EOF (3D-EOF) and extended EOF (EEOF), is put forward in this paper to test the ability of numerical model to simulate climate and its change. The 4D-E0F analysis is able to reveal not only the horizontal characteristic pattern of analyzed variable, and its corresponding annual and inter-annual variations, but also the vertical structural characteristics. The method suggested is then used to analyze the monthly mean 100-, 500-, 70G-, and 1000-hPa geopotential height fields (4941 grids and grid spacing 60 km) and their anomaly fields in 1989-1998 simulated by the MM5V3 from the RMIP (Regional Climate Model Inter-comparison Project for East Asia)-II, as well as their counterparts (used as the observed fields) from the NCEP/NCAR re-analysis dataset in the same period. The ability of MM5V3 in simulating East Asian climate and its change is tested by comparing the 4D-EOF analysis results of the simulated and observed datasets. The comparative analyzed results show that the horizontal pattern of the first eigenvector of the observed monthly mean geopotential height fields and its vertical equivalent barotropic feature were well simulated; the simulations of the first two eigenvectors of the observed monthly mean geopotential height anomaly fields were also successful for their horizontal abnormal distributions and significant equivalent barotropic features in the vertical were well reproduced; and furthermore, the observed characteristics, such as the variation with height, the annual and inter-annual variations of the monthly mean geopotential height/anomaly fields were also well reflected in the simulation. Therefore, the 4D-EOF is able to comprehensively test numerical model's ability of simulating the climate and its change, and the simulation ability of MM5V3 for the climate and its change in East Asia in the 1990s was satisfactory.  相似文献