排序方式： 共有36条查询结果，搜索用时 140 毫秒
1.
This short note reviews our thinking on how IGGOS can best achieve a high status within the set of global monitoring programmes. If such a high status can be obtained, then the importance of geodetic networks and services will be recognized more widely, and their activities will consequently be better resourced in the long term. One particular aspect concerns how IGGOS can complement the roles of the various IGOS partners within global monitoring. The different ways in which IGGOS can contribute to IGOS are outlined. 相似文献
2.
The GGOS as the backbone for global observing and local monitoring: A user driven perspective 总被引：1，自引：0，他引：1
A key geodetic contribution to both the three Global Observing Systems and initiatives like the European Global Monitoring for Environment and Security is an accurate, long-term stable, and easily accessible reference frame as the backbone. Many emerging scientific as well as non-scientific high-accuracy applications require access to an unique, technique-independent reference frame decontaminated for short-term fluctuations due to global Earth system processes. Such a reference frame can only be maintained and made available through an observing system such as the Global Geodetic Observing System (GGOS), which is currently implemented and expected to provide sufficient information on changes in the Earth figure, its rotation and its gravity field. Based on a number of examples from monitoring of infrastructure, point positioning, maintenance of national references frames to global changes studies, likely future accuracy requirements for a global terrestrial reference frame are set up as function of time scales. Expected accuracy requirements for a large range of high-accuracy applications are less than 5 mm for diurnal and sub-diurnal time scales, 2–3 mm on monthly to seasonal time scales, better than 1 mm/year on decadal to 50 years time scales. Based on these requirements, specifications for a geodetic observing system meeting the accuracy requirements can be derived. 相似文献
3.
地球科学涉及的研究对象和问题通常以长时间、大尺度、大规模为特征。这些研究不仅需要在实验室中进行，而且更需要大范围、长时间系列的实地观测资料。用于观测、实验、分析与计算的设施和仪器对地球科学领域的研究十分重要。GEO地球科学设施计划（1999—2003）是GEO历史上首次提出的“设施计划”，它从地球环境观测系统、计算系统、实验室系统及样本与资料存贮系统4个方面对NSF已拥有和拟发展的设施作了阐述。通过对GEO在1999年前已拥有、计划1999—2003年使用及目前的实行情况3方面对NSF用于地球环境观测系统的设施作较为全面的介绍。 相似文献
4.
潮汐数字记录应用软件 总被引：1，自引：0，他引：1
文中较详细地介绍了重力潮汐数字记录系统应用软件,主要包括数字采集的控制部分、观测资料的日常处理、重力仪记录格值的标定等一系列与台站观测有关的处理功能。它实现了潮汐信息从采集到成果处理的自动化,首次将48小时的Nakai潮汐数据预处理方法引入PC-1500计算机。它能有效地剔除、修正数字采集器本身无法识别的错误数据或干扰信号,使观测人员能根据拟合参量的变化,及时了解仪器的工作状况及记录系统灵敏度的变化。实践表明:此软件配合数字采集系统使用后大大提高了重力固体潮观测的整体水平。对这一软件作部分的改进后,可用于固体潮其它分量的观测。 相似文献
5.
仪器误差的精确测定和消除对于提高子午环的观测精度有着至关重要的意义。本文简单介绍了低纬子午环的观测原理和仪器结构，系统地探讨了它的各种仪器误差的来源、测定和处理方法。为了进一步完善采用组合固定角距法测定对径改正的方法，在第三章，研究了提高对径改正测量精度的方法，重新推导了对径改正的计算公式，并就某些具体的条件，对其进行了模拟验证，得到了较为满意的结果 相似文献
6.
中国地壳运动观测网络在地球科学研究中的应用前景 总被引：1，自引：1，他引：1
简要地介绍了中国地壳运动观测网络的概况和目前的进展,论述了地壳运动观测网络在地球科学研究中的重要作用和应用前景。其应用潜力主要体现在:①在中国地壳运动监测研究中发挥重要作用,成为中国地震预测预报研究的重要基础;②为地球动力学研究提供重要的依据;③建立维持ITRF地球参考框架、研究地球自转、极移和章动及变化;④精化、加密全国大地网和大地水准面;⑤在气象学中的应用;⑥研究电离层电子浓度及其变化规律;⑦提供精密近实时的GPS轨道参数;⑧为广域差分定位奠定基础。 相似文献
7.
8.
9.
Iain M. Suthers Jock W. YoungMark E. Baird Moninya RoughanJason D. Everett Gary B. BrassingtonMaria Byrne Scott A. CondieJason R. Hartog Christel S. HasslerAlistair J. Hobday Neil J. HolbrookHamish A. Malcolm Peter R. OkePeter A. Thompson Ken Ridgway 《Deep Sea Research Part II: Topical Studies in Oceanography》2011,58(5):538-546
The poleward flowing East Australian Current (EAC) is characterised by its separation from the coast, 100-200 nautical miles north of Sydney, to form the eastward flowing Tasman Front and a southward flowing eddy field. The separation zone greatly influences coastal ecosystems for the relatively narrow continental shelf (only 15-50 km wide), particularly between 32-34°S. In this region the continental shelf has a marked shift in the seasonal temperature-salinity relationship and elevated surface nitrate concentrations. This current parallels the portion of the coast where Australia’s population is concentrated and has a long history of scientific research. However, understanding of physical and biological processes driven by the EAC, particularly in linking circulation to ecosystems, is limited. In this special issue of 16 papers on the EAC, we examine the effects of climatic wind-stress forced ocean dynamics on EAC transport variability and coastal sea level, from ENSO to multi-decadal time scales; eddy formation and structure; fine scale connectivity and larval retention. Comparisons with the poleward-flowing Leeuwin Current on Australia’s west coast show differences in ecosystem productivity that can be attributed to the underlying physics in each region. On average there is double the chlorophyll a concentration on the east coast than the west. In comparison to the Leeuwin, the EAC may have less local retention of larvae and act as a partial barrier to onshore transport, which may also be related to the local spawning and early life history of small pelagic fish on each coast. Inter-annual variations in the EAC transport produce a detectable sea-level signal in Sydney Harbour, which could provide a useful fisheries index as does the Fremantle sea level and Leeuwin Current relationship. The EAC’s eddy structure and formation by the EAC are examined. A particular cold-core eddy is shown to have a “tilt” towards the coast, and that during a rotation the flow of particles may rise up to the euphotic zone and then down beneath. In a warm-core eddy, surface flooding is shown to produce a new shallower surface mixed layer and promote algal growth. An assessment of plankton data from 1938-1942 showed that the local, synoptic conditions had to be incorporated before any comparison with the present. There are useful relationships of water mass characteristics in the Tasman Sea and separation zone with larval fish diversity and abundance, as well as with long-line fisheries. These fisheries-pelagic habitat relationships are invaluable for fisheries management, as well as for climate change assessments.There is further need to examine the EAC influence on rainfall, storm activity, dust deposition, and on the movements by fish, sharks and whales. The Australian Integrated Marine Observing System (IMOS) has provided new infrastructure to determine the changing behaviour of the EAC and its bio-physical interaction with the coasts and estuaries. The forecasting and hindcasting capability developed under the Bluelink project has provided a new tool for data synthesis and dynamical analysis. The impact of a strengthening EAC and how it influences the livelihoods of over half the Australian population, from Brisbane to Sydney, Hobart and Melbourne, is just being realised. 相似文献
10.
全球Argo实时海洋观测网建设及应用进展 总被引：1，自引：0，他引：1
为了使各国政府、部门管理人员和科技工作者了解国际Argo计划的实施进展,以及帮助广大民众认识实施Argo计划的重要性和已经取得的初步成果,国际Argo信息中心、国际Argo科学组和国际Argo资料管理组联合编写了一本科普宣传册,题为“Argo,一个观测实时海洋的剖面浮标网”,经翻译、整理成文,以帮助国内读者深入了解和认识这一新世纪的重大国际观测计划。文章从陈述开展海洋观测的重要性和实施Argo计划的必要性着手,系统介绍了全球Argo实时海洋观测网建设的现状和Argo资料应用研究所取得的初步成果,以及Argo计划的发展前景等。 相似文献