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1.
利用依安县1971-2011年降水观测资料,采用线性倾向估计、累积距平、移动平滑等方法对近41a降水变化特征及变化趋势进行分析,得出近41a依安县年降水量呈缓慢增多趋势,且有15a、16a的周期变化。夏季降水量增多明显,秋季降水量却呈减少趋势。年降水量的增长主要源于夏季降水增长的贡献。同时,年降水增多、雨日增多、暴雨日减少,表明依安地区强降水的危害并不明显。  相似文献   

2.
利用承德市和承德县1964~2007年逐月降水资料,采用趋势分析等统计分析方法,对比分析了承德市城区、城郊降水变化特征及其城市化的可能性影响.结果表明:近44 a来承德市城区、城郊年降水量均呈减少趋势;城市化进程加快时期城区、城郊年、季降水量的变化速率出现明显差异:城区年降水量呈增加趋势,而城郊则呈明显减少趋势;城区各季降水量相对城郊呈增加趋势:冬季、夏季城区、城郊降水量都是呈减少趋势,但是城区的减少速率要明显小于城郊;春季、秋季城区、城郊降水量均呈增加趋势,但城区增加趋势要明显大于城郊.城区年、月≥0.1 mm降水日数减少趋势小于城郊减少趋势;城区、城郊降水量的不同变化速率可能是由于城区空气污染较重和城区绿地和水面增多而导致空气湿度增加的影响.  相似文献   

3.
山西省近50年气温和降水变化基本特征研究   总被引:1,自引:0,他引:1  
根据山西省近50年(1959-2008)108个地面气象观测站的年平均气温和年降水量系列数据,采用参数线性回归检验(LR)和非参数Mann-Kendall检验(MK)两种方法,从观测站、地级市、全省和山西省黄土高原地区综合治理地区4个层面,对山西省气温和降水的时空变化规律进行了研究.MK结果表明,(1)在108个地面站中,除河曲县站的年平均气温呈不显著减少趋势之外,其余107个站的年平均气温均呈升高趋势(+0.034~+0.896℃/10a("a"即"年";以下同).其中97个站的年平均气温显著升高,10个站的年平均气温升高不显著.除曲沃等8个站的年降水量呈不显著增加趋势之外,其余100个站的年降水量均呈减少趋势(-0.154~-57.750 mm/10a).其中16个站的年降水量显著减少,84个站的年降水量减少不显著.(2)11个地级市的年平均气温均表现出非常显著的升高趋势(+0.181~+0.417℃/10a).各市的年平均降水量均呈减少趋势(-6.954~-33.681 mm/10a).其中晋城、晋中、临汾和吕梁4市的降水量显著减少,太原、大同、阳泉、长治、朔州、运城和忻州7市的降水量减少不显著.(3)山西省的年平均气温呈极显著升高趋势(+0.295℃/10a),其年降水量呈显著减少趋势(-20.486 mm/10a).(4)山西省17个综合治理地区的年平均气温均呈显著升高趋势(+0.126~+0.375℃/10a).这17个地区的年平均降水量均呈减少趋势(-2.619~-34.417 mm/10a).其中5个地区的降水量呈显著减少趋势.总之,山西省的气温和降水在整体上分别呈显著升高和显著减少趋势,在较低层面上具有明显的空间异质性.对比分析同时表明,LR和MK所得的结果,就气温而言一致性非常高;就降水而言一致性则不确定(因研究层面不同很高或较低).  相似文献   

4.
根据细河流域内雨量站1966—2015年的日降水量数据,采用趋势系数法和气候倾向率法计算细河流域近50a的不同等级降水量与降水强度的变化趋势,通过MannKendall突变检验法检验突变,利用反距离权重空间插值法研究了空间分布特征.结果表明:细河流域近50a年降水量呈逐年增加的变化趋势,增加速率为0.432mm/a;年降水强度呈逐年降低的变化趋势,降低速率为0.162(mm·d-1)/a.各等级降水中小雨降水量及小雨降水强度均呈减少趋势,且小雨降水强度减少趋势较为明显.2003年中雨降水量发生增加突变,1983年小雨降水强度发生了减小突变.在空间分布上,小雨和中雨降水量由东北向西南呈逐渐递减至逐渐增加的变化趋势,暴雨及大暴雨降水量由东南向西北呈逐渐递减至逐渐增加的变化趋势.  相似文献   

5.
本文选取云南省1979-2016年125个气象台站秋季逐日降水量资料,利用Mann-Kendall趋势分析和突变检验方法,研究了秋季降水量降水强度趋势变化规律,发现年均降水量及小雨、中雨、大雨等级雨强大部分站点呈下降趋势,少数站点呈上升趋势;暴雨等级降水强度差异较大;年均雨强在较多站点存在显著性突变.应用经验正交函数(EOF)分解方法分析了秋季降水时空分布特征,从第一、二模态发现多年平均降水量从南向北逐渐减少,主要特征是大范围区域降水具有一致性,其次为滇中及以东以南与滇西及滇西北地区反向变化空间分布型态,这与云南省过去几十年天气状况及极端降水现象相符合.而后,分析了降水强度和降水日数对降水量的影响程度及其差异性.以雨强贡献大于雨日贡献为正,发现对于多年小雨、中雨、大雨等级,全局为负且具有一致性.年均降水量主要表现为西南、西北、东南地区为正,滇中及东部东北地区为负.至于暴雨,两者贡献值百分比差异明显且幅度较大,东北为负,西南为正,由东北向西南递增.可以认为雨量等级越大,降水强度对降水量影响越大.本研究在云南省降水研究中具有重要的现实意义.  相似文献   

6.
降水是最重要的天气要素之一,是城市水文循环关键组成部分.本文运用5a滑动平均、小波变换及MannKendall趋势检验方法,选取北京市通州区51a(1966—2016年)逐日降水资料,分析了通州区在年、季、月尺度上的降水特性.结果表明:年降水量以0.44mm·a-1的速率减少,且呈现出多个周期;降水量主要集中在夏季,占全年降水量的72.1%,且以2.33mm·a-1的速率减少,春季和秋季降水呈增加趋势,增加的趋势分别为0.36和1.12mm·a-1,冬季的变化趋势最弱,以0.03mm·a-1的趋势减小;月降水量主要集中在7和8月,占全年的50%以上,且分别以0.88和1.68mm·a-1的速率减少,降水量在12、1和2月没有变化的趋势.日降水量大于10和20mm的降水事件主要集中在夏季,降水时间减少是夏季降水减少的主因.  相似文献   

7.
以1951—2014年淮河流域29个站点月降水量数据为研究对象,运用线性趋势、累积距平、小波分析及空间分析等方法,分析了降水量时间和空间变化特征.结果表明:(1)1951—2014年,年、春、夏和秋季降水量呈不显著减少趋势,冬季降水量则具有不显著增加趋势.(2)春、秋和冬季易发生旱涝灾害,夏季降水量变化控制年降水量变化.(3)年降水量具有准2a和6a振荡周期.(4)东南部年和四季降水量多于西北部,这与我国年和四季降水量分布模式一致.(5)空间上,年和四季降水量变率中,年和夏季最大,降水量减少区域呈半环状包围降水量增加区域;整个流域冬季降水量几乎没有变化.  相似文献   

8.
气候变化对河北省水资源总量的影响   总被引:1,自引:0,他引:1  
利用近50 a河北省气候、水资源和预估资料,对气候变化与河北省水资源总量的关系进行了分析,结果表明:近50 a,河北省夏季降水量呈明显减少趋势,平均每10 a减少22 mm,年气温呈明显升高趋势,平均每10 a升高0.37℃.河北省气候暖干化趋势造成水资源总量明显减少,平均每10 a减少11.7%.多模式预估,到2050年,河北省年降水量将比1961—1990年增加约10%,年气温将升高约2℃,河北省水资源总量将增加15.3%.  相似文献   

9.
利用1951-2005年酒泉市肃州区气象观测站平均气温和降水量资料,运用多年趋势线、5a滑动趋势线、Mann-Kendall突变检验、滑动t检验和小波分析等方法对肃州区气候变化的主要特征、突变特点和周期特征进行分析.结果表明:近55a来,肃州区年平均气温呈明显上升趋势,年降水量呈微弱减少趋势.年平均气温和年平均降水量均有明显的突变,前者突变年份在1992年,后者突变年份较多,以1995年最显著.Morlel小波及其功率谱分析表明,年平均气温和年平均降水量的变化周期具有多尺度、多层次和多分辨的特性结构.其中,年平均气温存在21a和7.14 a(P≤0.16)的优势周期,年降水量存在21a,10.87a,9.09a和6.41a(P≤0.1)的显著周期,且中长期优势周期一致,中短周期不同.  相似文献   

10.
利用楚雄市1961~2010年50 a的气候和水资源等资料,分析了楚雄市近半个世纪以来气候的变化及其对径流、水资源变化的影响.分析结果表明:50 a来楚雄市各季和年平均气温均呈上升趋势,年平均气温以0.33℃/10 a速率上升,冬季平均气温增暖速率最为显著;近50 a来楚雄市年降水量有增多的趋势,以21.26mm/10 a的速度在递增.春季和夏季降水量增加较多;而冬季和秋季平均降水量则呈缓慢增多的趋势.水资源总量、地表水径流量、地下水呈减少趋势.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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