全球变暖背景下热带大气季节内振荡的变化特征及数值模拟     

刘芸芸  俞永强  何金海  张振国 《气象学报》2006,64(6):723-733

利用欧洲中期数值预报中心的ERA40再分析逐日的200 hPa风场资料,选取1958—1977年和1980—1999年各20年,对比分析了在全球变暖背景下前后两个时段热带大气季节内振荡(ISO)的特征及其变化。研究表明:近20 a来,原来在赤道中太平洋上活跃的ISO减弱,而在中印度洋、孟加拉湾地区ISO变得活跃;全球变暖背景下,ISO的强度变化幅度加大,表明ISO更加活跃,且季节变化明显,冬、春季强,夏、秋季弱;对流层上层的纬向风能量更集中于1—3波,ISO的频率有加大的趋势。还利用中国科学院大气物理研究所LASG发展的耦合气候系统模式FGOALS-1.0g中的控制试验及其二氧化碳浓度加倍试验结果,分别对应实测资料的前后20年进行对比分析。发现模式对ISO的空间结构模拟较好,但低估了ISO的强度;时空谱分析表明模式结果中包含有更多的纬向风的高频成分,由于能量的分散,导致对ISO活动强度的低估。但通过对模式的控制试验和温室气体增加试验结果的对比分析,发现耦合模式还是较好地反映出在全球变暖背景下ISO在中印度洋、孟加拉湾地区变得活跃、频率加大等变化特征。  相似文献   

Forestry as a streamflow reduction activity in South Africa: Discussion and evaluation of the proposed procedure for the assessment of afforestation permit applications in terms of water sustainability     

I. J. Van der Walt  A. Struwig  J. R. J van Rensburg 《GeoJournal》2004,61(2):173-181

Commercial afforestation in South Africa dates back to the 1870s and started as an alternative to the fast disappearing indigenous timber resource. It involves the planting of exotic timber species and has impacts on water resources, soil biodiversity, landscapes, etc. Commercial afforestation of land has been subjected to regulation through the Afforestation Permit System (APS) since 1972, primarily to protect the national water resource. Since the APS no longer adequately dealt with afforestation regulation, it was replaced in 1999 with a procedure that was supposed to integrate the requirements of relevant legislation and general environmental management principles. This paper is a theoretical review of the background and development of the new South African Streamflow Reduction Activities licensing procedure, as well as whether it complies with the requirements of an environmental management system such as ISO 14001. The main conclusion is that the new procedure, although an improvement on the previous procedure, still has shortcomings especially with regard to the operational and decommissioning phases of forestry in South Africa. It is recommended that these aspects be addressed in order to mitigate the impact of forestry on water sustainability in South Africa. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

加强基础测绘管理、提高测绘产品质量     

刘俊杰  刘焕  王贵章 《测绘与空间地理信息》2001,24(2):28-30

文章分析了测绘产品质量存在的问题及其成因 ,由此总结出测绘质量管理工作的两个方面 ,并对加强这两个方面的工作进行了深入探讨 ,最后提出建立测绘项目管理数据库 ,运用现代化手段保障测绘主管部门的质量监督管理。  相似文献   

Urban Sustainability Indicators: how do Australian city decision makers perceive and use global reporting standards?     

Derui Deng  Shiyao Liu  Lawrence Wallis  Elizabeth Duncan 《The Australian geographer》2017,48(3):401-416

The introduction in 2014 of the first globally standardised sustainability metric for cities, ISO 37120, transformed the concept of scalability for sustainable city indicators. Our study uses original research involving producers and consumers of urban sustainability indicators (USIs), including ISO 37120, to review the current use of sustainability indicators (SIs) in Sydney and ascertain the use-value of internationally standardised USIs as perceived by professionals in the field. Our findings show that managers of cities use SIs in a variety of ways, yet links between SIs and organisational decision making are often weak. The cost of adaptation to a new indicator set may be prohibitive, especially for smaller city governments. Larger cities are seen to benefit more from international exposure and comparison. Highlighting ISO 37120 should be valued for the opportunity it presents for comparative learning regarding the nature of a sustainable city rather than its benchmarking potential. This article recommends that the process of achieving a sustainable city should be informed by ‘strong’ rather than ‘weak’ sustainability; in this regard ISO 37120 has potential for refinement. Further research is needed into determining aspects of city comparability and methods for linking USI data to government decision making in order to achieve sustainability outcomes.  相似文献   

Unidata’s Common Data Model mapping to the ISO 19123 Data Model   总被引：1，自引：1，他引：0  

Stefano Nativi  John Caron  Ben Domenico  Lorenzo Bigagli 《Earth Science Informatics》2008,1(2):59-78

Access to real-time distributed Earth and Space Science (ESS) information is essential for enabling critical Decision Support Systems (DSS). Thus, data model interoperability between the ESS and DSS communities is a decisive achievement for enabling cyber-infrastructure which aims to serve important societal benefit areas. The ESS community is characterized by a certain heterogeneity, as far as data models are concerned. Recent spatial data infrastructures implement international standards for the data model in order to achieve interoperability and extensibility. This paper presents well-accepted ESS data models, introducing a unified data model called the Common Data Model (CDM). CDM mapping into the corresponding elements of the international standard coverage data model of ISO 19123 is presented and discussed at the abstract level. The mapping of CDM scientific data types to the ISO coverage model is a first step toward interoperability of data systems. This mapping will provide the abstract framework that can be used to unify subsequent efforts to define appropriate conventions along with explicit agreed-upon encoding forms for each data type. As a valuable case in point, the content mapping rules for CDM grid data are discussed addressing a significant example.

Lorenzo BigagliEmail: URL: www.imaa.cnr.it

  相似文献   

渔用高强度聚乙烯和普通聚乙烯绞捻网片的拉伸力学性能比较研究   总被引：6，自引：0，他引：6  

石建高  王鲁民 《海洋科学》2007,31(5):20-24

为给深水网箱设计与渔用材料的合理选配提供依据,应用ISO1806等对渔用高强度聚乙烯绞捻网片(以下简称HSPE绞捻网片)和普通聚乙烯绞捻网片(以下简称PE绞捻网片)的拉伸力学性能进行了比较研究。结果表明,(1)在同等条件下,36股HSPE绞捻网片的网目连接点断裂强力和网片单线断裂强力分别比52股PE绞捻网片增加了3.1%,3.7%;而前者的目脚直径和网片阻力可较后者减少19.6%。(2)对网片强力进行了再现性研究,36股HSPE和52股PE绞捻网片网目连接点断裂强力的标准偏差分别为35.93N,25.61N,再现性标准偏差分别为31.07N,36.93N;网片单线断裂强力的标准偏差分别为19.91N,13.49N,再现性标准偏差分别为20.48N,15.49N;网片强力测试数据的变异系数均小于4%;表示测试结果的分散性较小。(3)36股HSPE绞捻网片成本可较52股PE绞捻网片减少38.9%,其在渔业生产中进行推广应用具有可行性。(4)GB/T4925作为一个标准,对绞捻网片来说,存在不足,建议对GB/T4925进行修订。  相似文献   

SWS-Detector Glitch Effect Correction     

E. Wieprecht  E. Wiezorrek  L. Haser 《Experimental Astronomy》2000,10(2-3):199-214

We describe how the ISO-SWS (Infrared Space Observatory – Short Wavelength Spectrometer) software packages detect various glitch events i.e. high energy particle hits effecting the SWS detectors. A rough classification of glitch types is given. The events cause an instantaneous change in the slope of the SWS detector read outs followed by a distortion of the further samples, so called glitch tails. As a consequence the S/N ratio and photometric accuracy are reduced.Different strategies, how to remove the resulting distortion of the detectorread-out-ramp after a hit, are presented. The methods of the basic SWS software packages, the Pipeline and Interactive Analysis, will be discussed. The Pipeline has to treat glitch effects automatically. The Interactive Analysis system provides the user with a comfortable Graphical User Interface (GUI) for Trend Analysis, detailed analysis of certain glitches and the testing of new algorithms.  相似文献   

通过质量认证与国际标准接轨——海洋技术研究所的质量认证     

廉双喜 《海洋技术学报》2000,19(1):18-22

本文阐述了国家海洋局海洋技术研究所在ＩＳＯ９００１质量体系认证工作中的做法和经验。  相似文献   

面向发生的地学数据分类方案及其元数据扩展研究     

宋春桥  游松财  柯灵红 《测绘软科学研究》2010,(4):22-28

在分析地学数据特点和共享需求的基础上,阐述数据分类对于人们认识地球以及地学研究的重要性,并综述和评价了目前地学领域已有的各种分类研究。这些分类研究大致可归纳为探索型、应用型和综合型3种。由于地学数据应用的多学科交叉、多源异构等特性,分类系统很难满足系统性、一致性、易扩展性等原则。本文从数据发生的角度,探索新的数据分类方案,将地学数据分为器测数据、调查数据和过程数据三大类。从数据本质特征对其进行描述,学科应用仅作为数据的元数据对其标志,从而很好地消除了上述问题。此外,本文基于ISO19115地理信息核心元数据扩展模型,将地理信息元数据标准拓展到整个地学领域的数据描述,构建适应该地学数据分类方案的元数据体系。  相似文献   

上海市规划和国土资源信息化运维管理     

杨健  汪一琛  马卫平 《国土资源信息化》2010,(1):43-49

上海市规划和国土资源信息化运维团队从专注技术向运维管理转变。以优质服务,面向业务、面向客户来开展IT运维工作。  相似文献