“0801南方雪灾”水汽通量与降水关系的SVD分析   总被引：2，自引：0，他引：2  

杨玮  何金海  王佳  王盘兴 《热带气象学报》2011,(5):697-702

利用2008年1月10日—2月2日的NCEP/NCAR逐日风场、比湿、地面气压资料以及中国地面国际交换站194站的逐日降水资料,分析我国“0801南方雪灾”期间水汽通量场的特征,结果表明我国南方是整层水汽通量及其散度的高值区。用奇异值分解（SVD）方法,分析了水汽输送通量异常场和降水异常场之间的关系,揭示出两对统计显著且天气意义清晰的耦合模态。其中,第一对模态的方差贡献率为81.50%,相应左、右奇异向量时间系数的相关系数为0.80,主要描述源自孟加拉湾及南海的西南风水汽输送异常增强并在我国川、滇、黔交界处及粤、闽、赣一带辐合时,长江以南大部分地区多雨;第二对模态方差贡献率为8.80%,相关系数为0.64,主要描述当中国大陆东部有源自西太平洋的水汽输送异常增强并在广西-浙江沿线区域辐合时,长江中下游流域多雨,但华南三省（广西、广东和福建）少雨。   相似文献   

采用相关分析法研究降雨对水位的影响     

张清秀  陈莹  陈懿德  黄晓华 《华南地震》2012,(2):104-111

地下水位动态受降雨影响显著,且由于降雨的持续时间、强度和面积的不同,由降雨引起的水位变化形态也复杂多样。为了能直观地判别降雨对水位的影响,排除水位资料中降雨的影响成分,本文采用水位月变化量与降雨月累计值作相关分析后得到的余差值,作为水位微动态研究对象。选用与降雨关系分别为显著、一般、不相关的连江江南井、泉州局一号井、福州浦东井水位进行分析,结果显示水位月变化量均表现了高值异常,异常与地震时间的对应关系有3个震前异常,2个同震异常、1个震后效应、1个无震异常。  相似文献   

基于MTM-SVD方法的黄河流域夏季降水年际变化及其主要影响因子分析   总被引：7，自引：1，他引：6  

王春学  李栋梁 《大气科学》2012,36(4):823-834

应用中国气象台站积雪日数资料和NCEP/NCAR再分析资料以及多锥度—奇异值分解方法 (MTM-SVD),分析了近50年来黄河流域夏季降水的时空变化及其影响因子.发现黄河流域夏季降水存在显著的2～3年周期.在准3年周期上黄河流域夏季降水对前冬青藏高原东部积雪日数有很好的响应,当前冬高原积雪日数以正 (负) 异常为主时,接下来的夏季黄河流域降水偏少 (多).这种响应存在年代际变化,在1983年之前最为明显,1983~1993年是个调整时期,1993年以后又开始明显.在准2年周期上黄河流域夏季降水对前冬西太平洋暖池SST有很好的响应,当前冬西太平洋暖池SST偏高 (低) 时,接下来的夏季黄河流域降水表现为东多 (少)西少 (多) 型.这一响应同样存在年代际变化.前冬高原积雪和西太平洋暖池SST是影响黄河流域夏季降水的重要因子.  相似文献   

开鲁盆地陆西凹陷热埋藏史研究     

王学军  张之一 《地球科学与环境学报》1994,(1)

本文通过对有机质干酪根类型的分析，重新确定了陆面凹陷时间温度指数（ＴＴＩ）值计算的基准温度及古地温梯度，对凹陷内沉积厚度大的地方进行了沉积构造史的恢复，并建立了凹陷热埋藏史模式．据此计算了凹陷内部分ＴＴＩ值．通过研究，指出了目前对凹陷进行石油勘探的有利生油岩层位．  相似文献   

Historical and future quantification of terrestrial carbon sequestration from a Greenhouse-Gas-Value perspective     

《Global Environmental Change》2015

Terrestrial ecosystems provide a range of important services to humans, including global and regional climate regulation. These services arise from natural ecosystem functioning as governed by drivers such as climate, atmospheric carbon dioxide mixing ratio, and land-use change. From the perspective of carbon sequestration, numerous studies have assessed trends and projections of the past and future terrestrial carbon cycle, but links to the ecosystem service concept have been hindered by the lack of appropriate quantitative service metrics. The recently introduced concept of the Greenhouse Gas Value (GHGV) accounts for the land-atmosphere exchanges of multiple greenhouse gases by taking into consideration the associated ecosystem pool sizes, annual exchange fluxes and probable effects of natural disturbance in a time-sensitive manner.We use here GHGV as an indicator for the carbon sequestration aspects of the climate regulation ecosystem service, and quantify it at global scale using the LPJ-GUESS dynamic global vegetation model. The response of ecosystem dynamics and ecosystem state variables to trends in climate, atmospheric carbon dioxide levels and land use simulated by LPJ-GUESS are used to calculate the contribution of carbon dioxide to GHGV. We evaluate global variations in GHGV over historical periods and for future scenarios (1850–2100) on a biome basis following a high and a low emission scenario.GHGV is found to vary substantially depending on the biogeochemical processes represented in LPJ-GUESS (e.g. carbon–nitrogen coupling, representation of land use). The consideration of disturbance events that occur as part of an ecosystem's natural dynamics is crucial for realistic GHGV assessments; their omission results in unrealistically high GHGV. By considering the biome-specific response to current climate and land use, and their projections for the future, we highlight the importance of all forest biomes for maintaining and increasing biogeochemical carbon sequestration. Under future climate and carbon dioxide levels following a high emission scenario GHGV values are projected to increase, especially so in tropical forests, but land-use change (e.g. deforestation) opposes this trend. The GHGV of ecosystems, especially when assessed over large areas, is an appropriate metric to assess the contribution of different greenhouse gases to climate and forms a basis for the monetary valuation of the climate regulation service ecosystems provide.  相似文献   

The uses of value     

Daniel Miller   《Geoforum》2008,39(3):1122-1132

This paper proposes a new theory of value based on the observation of how people use this term. In everyday life the word value is commonly used to refer equally to what might be regarded as the incommensurable polarity between value as price, and value as priceless, sometimes portrayed as the contrast between value and values. My theory starts from trying to learn how people manage to use value as a means of bridging this divide. As such it opposes itself to ‘bottom-line’ theories of value. These range from vulgarised forms of Marx’s labour theory of value, to the way management consultants tried to impose a universal belief in shareholder value. An example is provided of how such bottom-line thinking undermined a UK government audit called best-value, and is also found in highly reductionist attempts to impose new-age values in management. By contrast, examples are given of how value is created in the process of bridging the divide between value and values, starting from the work of Zelizer and the case of concubines in 5th century BC Athens. Further examples range from the department store John Lewis to the Swedish social democratic state. Finally the application of this theory is considered in relation to a recent attempts to evaluate the impact of the mobile phone on low-income Jamaicans.  相似文献   

Cost and value of multidisciplinary fixed-point ocean observatories     

《Marine Policy》2016

Sustained ocean observations are crucial to understand both natural processes occurring in the ocean and human influence on the marine ecosystems. The information they provide increases our understanding and is therefore beneficial to the society as a whole because it contributes to a more efficient use and protection of the marine environment, upon which human livelihood depends. In addition the oceans, which occupy 73% of the planet surface and host 93% of the biosphere, play a massive role in controlling the climate. Eulerian or fixed-point observatories are an essential component of the global ocean observing system as they provide several unique features that cannot be found in other systems and are therefore complementary to them. In addition they provide a unique opportunity for multidisciplinary and interdisciplinary work, combining physical, chemical and biological observations on several time scales. The fixed-point open ocean observatory network (FixO3) integrates the 23 European open ocean fixed-point observatories in the Atlantic Ocean and in the Mediterranean Sea. The programme also seeks to improve access to key installations and the knowledge they provide for the wider community, from scientists, to businesses, to civil society. This paper summarises the rationale behind open ocean observatories monitoring the essential ocean variables. It also provides an estimate of the costs to operate a typical fixed-point observatory such as those included in the FixO3 network. Finally an assessment of the type of data and services provided by ocean observations and their value to society is also given.  相似文献   

用赢得值法进行测绘项目进度和费用控制     

吴玉忱  王敬华 《测绘与空间地理信息》2016,(1):222-224

基于工程项目管理理论,主要探讨了用赢得值法进行测绘项目进度和费用控制的方法,对测绘工程项目进行有效管理,从而实现项目目标,提高项目管理水平。  相似文献   

江西九江-瑞昌震区的尾波衰减特征初探   总被引：2，自引：1，他引：1  

吕坚  朱新运  高建华  沈小七  汤兰荣  肖建华 《地震》2006,26(4):15-21

根据单次散射模型,利用数字地震记录资料研究和讨论了江西省九江-瑞昌震区的尾波衰减特征,获得了可信的结果。经过计算,震中距30 km内的5个地震台站得到Q0值在75~79内波动。η值大体可以分为两类:九江台和范镇台η值为0.86~0.88;丁家山、狮子洞和武皎台η值为0.94~0.97,这种差别可能与台站方位有一定的关系。考虑到此次地震的破裂尺度不会太大,可采用后3个台的计算结果,拟合得到九江-瑞昌震区尾波Qc值随频率的变化关系为Qc(f)=(77.5±15.6)f0.96±0.09。九江-瑞昌震区的Q0值为77.5,η值为0.96,与云南武定、施甸地区接近,这种类似现象是构造运动活跃地区的特征体现还是反映了中强地震破裂区局部介质性质的一种共性,有待于进一步深入研究。本研究参与计算的5个台站最大尾波流逝时间为40~44 s,得到的平均采样体深度约为53 km,相对江西地区地壳平均厚度33 km而言,结果反映的是九江-瑞昌震区地壳和上地幔顶部的介质性质。  相似文献   

Interpreting Economics,Rhetoric and Sustainable Development: Some implications for policy determination     

SARAH LUMLEY 《The Australian geographer》1999,30(1):35-49

Many of the controversies about environmental resource use relate to the perceived conflict between economics and conservation. This conflict might have been resolved with general acceptance of the concept of sustainable development, and with a more transparent and honest use of economics terminology. However, interpretation and application of this concept appear to have led to some further conflicts between perceptions of economics and the environment, partly because commerce and development are sometimes portrayed as having the same meaning. Commercial activity resulting from the use of natural resources is often held to promote social good, while conservation of natural resources, many argue, renders the wealth which may be obtained from such resources unavailable. The latter is deemed to be bad for society. However, although in contemporary parlance economics is usually restricted implicitly to issues concerning commerce, finance and profit, economic theory requires the consideration also of intangible values, such as environmental damage. Environmental and other economists have worked hard to stress the importance of non-financial values in economic theory, and to ensure that they are included in economic analysis. However, these latter aspects of economics are not generally known to the wider public, partly because of the tendentious manner in which interested parties often use economics. When positions are argued on the basis of economics, the arguments are frequently expressed in language designed to persuade members of the community that all commercial activity is in the interests of society, while incurring minimal costs. In these circumstances, economics might be viewed as a form of rhetoric. Anyone assessing the merits of such arguments ought to consider carefully what this rhetoric really means. This is especially important in discussions concerning sustainable development, which is understood by some to mean sustainable, or sustained, commerce.  相似文献