共查询到20条相似文献，搜索用时 15 毫秒
1.
D. Bala Subrahamanyam Radhika Ramachandran S. Indira Rani S. Sijikumar T. J. Anurose Asish Kumar Ghosh 《Natural Hazards》2012,61(3):893-910
Accurate knowledge of different meteorological parameters over a launch site is very crucial for efficient management of satellite
launch operations. Local weather over the Indian satellite launch site located at Sriharikota High Altitude Range (SHAR: 13.72°N,
80.22°E) is very much dependent on the atmospheric circulation prevailing over the Bay of Bengal oceanic region and topography-induced
convective activities. With a view to providing severe weather threat prediction in terms of launch commit criteria (LCC),
two numerical atmospheric models namely high-resolution regional model (HRM) and advanced regional prediction system (ARPS)
are made operational over SHAR in a synoptic and mesoscale domain, respectively. In the present research article, two launch
campaigns through Polar Satellite Launch Vehicle (PSLV-C11 and PSLV-C12) when contrasting weather conditions prevailed over
the launch site are chosen for demonstration of potential of two models in providing location-specific short-to-medium-range
weather predictions meeting the needs of LCC. In the case of PSLV-C11 campaign, when the launch site underwent frequent thundershower-associated
rainfall, ARPS model–derived meteorological fields were effectively used in prediction of probability of the wet spells. On
the other hand, Bay of Bengal underwent severe cyclonic storm during PSLV-C12 campaign, and its formation was reasonable captured
through HRM simulations. It is concluded that a combination of HRM and ARPS provide reliable short-to-medium-range weather
prediction over SHAR, which has got profound importance in launch-related activities. 相似文献
2.
通过北斗卫星定位系统终端在东昆仑试验区不同海拔高度、天气条件、地貌构造及移动状态下的示范应用,总结归纳了该定位系统在野外地质调查中的应用特点及不足,并对未来北斗卫星定位系统的应用进行了分析。试验应用结果表明,北斗卫星定位系统在提高地质调查效率、保障野外地质调查人员人身安全、野外作业管理以及野外应急服务等方面均可发挥重要作用。系统目前存在的定位精度不尽如人意、定位信号受地貌构造、天气和移动方式影响不甚稳定的现象,是其今后发展中需要重点解决的问题。 相似文献
3.
Paul Poli 《Comptes Rendus Geoscience》2010,342(4-5):357-369
Measurements of the atmosphere by satellite were first collected in the 1960s. However, it was not until the mid-1990s that these observations were translated into systematic improvements of numerical weather forecasts. We present here the data and methodology of data assimilation that enabled this achievement. Data assimilation is essentially a filtering processing that exploits the (assumed) known error statistical properties of the observations and of the underlying numerical model in which data are assimilated. It is also a process which corrects the state of the numerical model with physical observations of the real world. This part relies on (assumed) known physical laws to relate meteorological quantities (such as temperature, humidity, pressure, and wind) to observables. Atmospheric data collected by satellite all come from the interaction of electromagnetic waves with the atmosphere. Satellite data assimilation has greatly supported the progress in numerical weather prediction and holds promises for climate studies, for example via reanalysis. 相似文献
4.
我国海洋光学遥感应用科学研究的新进展 总被引：15，自引：1，他引：14
20世纪90年代以来,我国航天遥感事业的发展促进了海洋光学应用科学的发展,特别是通过近几年来,国家“863”高新技术计划的实施,在该方面有了新进展。文章将着重介绍光学遥感信息的大气校正、光学遥感海洋环境信息提取、光学遥感在赤潮与溢油监测等3个方面的应用科学新进展,并提出了在我国进一步深入开展海洋光学遥感应用科学技术研究的建议。 相似文献
5.
卫星遥感探测大气CO2浓度研究最新进展 总被引：4，自引：0，他引：4
大气CO2是一种重要的长寿命温室气体,卫星遥感探测大气CO2浓度,可以连续地获得其全球时空分布变化情况,进而提高对大气CO2源汇分布及区域和全球碳循环的认识,进一步增强对全球气候变化的研究和预测。卫星遥感探测大气CO2浓度已经开始成为一个新的研究领域,文章综合论述了利用卫星平台遥感探测大气CO2浓度分布的最新研究状况。首先简单地叙述了现阶段对大气CO2浓度时空分布和变化情况的直接仪器观测结果,在此基础上比较全面地综述了卫星遥感测量大气CO2浓度的主要方法及获得的结果,包括利用近红外反射太阳光谱或地气热红外发射辐射光谱及两者的组合进行得模拟和卫星实测反演研究,最后简单地进行了总结和展望。 相似文献
6.
Digital as well as photographic satellite image data offer a high potential of topographic and thematic information. The paper discusses the application of such data for mapping purposes. For the compilation of conventionalTopographic Maps the requirements concerning the geometrical accuracy can easily be met for 1 : 50,000 or even 1 : 25,000. However, the interpretability of the features that are relevant for topography is often the critical factor. Only the Russian KWR-1000 data are suitable for mapping topographic features in 1 : 25,000. Main emphasis is laid on a new map type, theSatellite Image Map. The authors describe the satellite image mapping procedures developed at the Technical University of Berlin and applied in practice by FPK Consulting Engineers. Some related problems are discussed in details, eg mosaicking, merging of different types of data, and integration of graphical elements. An increase in cartographic applications of satellite remote sensing data is anticipated. 相似文献
7.
Incorporation of cloud- and precipitation-affected radiances from microwave satellite sensors in data assimilation system has a great potential in improving the accuracy of numerical model forecasts over the regions of high impact weather. By employing the multiple scattering radiative transfer model RTTOV-SCATT, all-sky radiance (clear sky and cloudy sky) simulation has been performed for six channel microwave SAPHIR (Sounder for Atmospheric Profiling of Humidity in the Inter-tropics by Radiometry) sensors of Megha-Tropiques (MT) satellite. To investigate the importance of cloud-affected radiance data in severe weather conditions, all-sky radiance simulation is carried out for the severe cyclonic storm ‘Hudhud’ formed over Bay of Bengal. Hydrometeors from NCMRWF unified model (NCUM) forecasts are used as input to the RTTOV model to simulate cloud-affected SAPHIR radiances. Horizontal and vertical distribution of all-sky simulated radiances agrees reasonably well with the SAPHIR observed radiances over cloudy regions during different stages of cyclone development. Simulated brightness temperatures of six SAPHIR channels indicate that the three dimensional humidity structure of tropical cyclone is well represented in all-sky computations. Improved correlation and reduced bias and root mean square error against SAPHIR observations are apparent. Probability distribution functions reveal that all-sky simulations are able to produce the cloud-affected lower brightness temperatures associated with cloudy regions. The density scatter plots infer that all-sky radiances are more consistent with observed radiances. Correlation between different types of hydrometeors and simulated brightness temperatures at respective atmospheric levels highlights the significance of inclusion of scattering effects from different hydrometeors in simulating the cloud-affected radiances in all-sky simulations. The results are promising and suggest that the inclusion of multiple scattering radiative transfer models into data assimilation system can simulate the cloud-affected microwave radiance data which provide detailed information on three dimensional humidity structure of the atmosphere in the presence of cloud hydrometeors. 相似文献
8.
An overview of satellite remote sensing technology used in China’s environmental protection 总被引：2，自引：0，他引：2
Shaohua Zhao Qiao Wang Ying Li Sihan Liu Zhongting Wang Li Zhu Zifeng Wang 《Earth Science Informatics》2017,10(2):137-148
Satellite remote sensing technology has been widely used in environmental protection in China. Based on China’s environmental protection characteristics, this paper reviews the application advancements of optical, infrared, microwave and hyperspectral satellite remote sensing techniques in atmospheric environment, water environment and ecological environment, respectively, including the atmospheric environment monitoring of aerosols, particulate matter, pollution gases, and greenhouse gases; the water environment monitoring of water blooms water quality, oil spills, water pollution and drinking water safety; the ecological environment monitor of national nature reserves, environmental damages from mines development, soil contamination, urban/rural ecological environment and biodiversity richness. Furthmore, it summarizes the limitations and future directions of satellite remote sensing studies in China environmental protection. The paper specifically notes that the development of high-resolution satellite remote sensing technology, as well as the launch and use of China series satellites could significantly improve the level of government’s environmental management. 相似文献
9.
10.
Abdurrahman Geymen 《Arabian Journal of Geosciences》2014,7(2):827-837
The development of satellite technology is rapidly increasing the evolution of remote sensing. Satellite images give extensive useful information about the land structure that is easily manageable in the process of generating true, high-speed information which allows the forecasting of future environmental and urban planning. Remote sensing comprises active and passive systems. Passive sensors detect natural radiation that is emitted or reflected by the object or surrounding area being observed. Active systems which produce their own electromagnetic energy and their main properties are their ability of collecting data in nearly all atmospheric conditions, day or night. These systems are frequently used to generate a digital elevation model (DEM) because they cover large areas. DEM supplies essential data for applications that are concerned with the Earth’s surface and DEMs derived from survey data are accurate but very expensive and time consuming to create. However, the use of satellite remote sensing to provide images to generate a DEM is considered to be an efficient method of obtaining data. Interferometric Synthetic Aperture Radar (InSAR) is a new geodetic technique for determining earth topography. InSAR measurements are highly dense and they only give information in Line of Sight of Radar. In the study, interferograms were produced from the InSAR images taken by ERS satellites in 1992 and 2007 and we developed the methods to generate a DEM using the InSAR technique and present the results relating to Kayseri Province in Turkey. The accuracy of the DEM derived from the InSAR technique is evaluated in comparison with a reference DEM generated from contours in a topographical map. 相似文献
11.
从最优化数学理论角度对大气廓线物理反演以及卫星辐射率资料直接同化中的最优化算法进行了回顾。分析了各种方法的优点和缺点、联系和差别。总结了卫星大气遥感反演问题的求解思路。对大气廓线反演研究中几种主要的目标函数和寻优策略进行了分析,着重分析了目前作为各数值预报中心和卫星数据处理中心业务数值产品核心算法的牛顿非线性迭代法的不足之处,并对其改进途径进行了探讨。引入了Levenberg-Marquardt方法及信赖域方法用于大气廓线反演,使反演算法的收敛性质得到改善。 相似文献
12.
INSAT-3D is the new generation Indian satellite designed for improved Earth observations through two payloads – Imager and Sounder. Study was conducted with an aim of simulating satellite level signal over land in the infrared channels of the Imager payload
using a radiative transfer model MODTRAN. Satellite level at-sensor radiance corresponding to all four infrared channels of
INSAT-3D Imager payload is obtained using MODTRAN and sensitivity of at-sensor radiance was inferred as a function of input
parameters namely, surface temperature, emissivity, view angle and atmospheric water vapour, which is helpful in understanding
the signal simulation scheme needed for retrieving a very critical parameter namely, land surface temperature. 相似文献
13.
黑河流域遥感—地面观测同步试验：科学目标与试验方案 总被引：44，自引：17，他引：27
介绍了黑河流域遥感-地面观测同步试验的科学背景、科学问题、研究目标以及观测试验方案和观测系统布置.总体目标是,开展航空-卫星遥感与地面观测同步试验,为发展流域科学积累基础数据;发展能够融合多源遥感观测的流域尺度陆面数据同化系统,为实现卫星遥感对流域的动态监测提供方法和范例.以具备鲜明的高寒与干旱区伴生为主要特征的黑河流域为试验区,以水循环为主要研究对象,利用航空遥感、卫星遥感、地面雷达、水文气象观测、通量观测、生态监测等相关设备,开展航空、卫星和地面配合的大型观测试验,精细观测干旱区内陆河流域高山冰雪和冻土带、山区水源涵养林带、中游人工绿洲及天然荒漠绿洲带的水循环和生态过程的各个分量;并且以航空遥感为桥梁,通过高精度的真实性验证,发展尺度转换方法,改善从卫星遥感资料反演和间接估计水循环各分量及与之密切联系的生态和其他地表过程分量的模型和算法.由寒区水文试验、森林水文试验和干旱区水文试验,以及一个集成研究--模拟平台和数据平台建设组成.拟观测的变量划分为5大类,分别是水文与生态变量、驱动数据、植被参数、土壤参数和空气动力参数.同步试验在流域尺度、重点试验区、加密观测区和观测小区4个尺度上展开.布置了加密的地面同步观测、通量和气象水文观测、降雨、径流及其他水文要素观测网络;使用了5类机载遥感传感器,分别是微波辐射计、激光雷达、高光谱成像仪、热红外成像仪和多光谱CCD相机;获取了丰富的可见光/近红外、热红外、主被动微波、激光雷达等卫星数据. 相似文献
14.
15.
基于商用运输平台的流动大气和环境监测系统 总被引：2，自引：2，他引：0
高时空精度大气观测资料的缺乏,仍是制约提高数值天气预报水平和深入开展大气科学研究的一个主要因素。为了克服这一问题,除了研制自动化程度高、测量精度高和性能价格比高的仪器设备来装备现有的定点大气观测网外,还应建设一些流动的大气监测系统,以获得常规大气观测台站空档间（如大洋、山区和荒漠等无人区）的天气现象和大气环境变化的信息。然而,在现有台站网之外,再重新建立并运行一个流动专业观测网,既不经济也是不现实的。随着交通和通信技术的快速发展,利用民用的交通运输工具（主要是商船、民航飞机、火车甚至长途汽车）,加装大气环境监测传感器,逐步建立海陆空三位一体的流动大气环境监测系统已成为可能。 相似文献
16.
大气波导是对流层中具有异常大气折射率梯度的大气层,对于评估和预测电磁波传播和海上探测通信系统等具有重要的科学意义和应用价值.以海上发生的大气波导类型为线索总结了与大气波导相关的研究方法.在蒸发波导研究中以相似理论为基础,开发蒸发波导诊断模型为重点,开展区域海域适应性研究;海上悬空波导和表面波导从早期的定性分析到目前精确定量研究过程中,中尺度数值模式逐渐成为极其重要的研究手段,不仅提高了特定天气过程中大气波导模拟预测精度,而且在此基础上开展区域大气波导环境研究,分析其出现规律、气候原因等.针对海上大气波导研究现状,借鉴气象上的手段和技术,开展海上水文气象调查和电波传播实验,结合中尺度数值模式和海气耦合模式,采用同化技术和集合预报等手段,提高海上低空大气波导量化精度. 相似文献
17.
Dr. Claire L. Parkinson 《GeoJournal》1989,18(1):9-20
In spite of the importance of sea ice to polar climates, sea ice/climate studies have been limited in the past due to the lack of consistent, long-term, global sea ice records. Satellite passive microwave technology, available since the early 1970s, now provides the potential of generating the desired long-term data sets. With passive microwave data, global sea ice distributions can be mapped on a routine basis every few days, to a spatial resolution on the order of 30 km. The sea ice records generated so far from such satellite data have already been used in many scientific investigations, helping to quantify global sea ice distributions and their seasonal and interannual variations, and to illuminate possible ice/ocean and ice/atmosphere interactions. The results to date augur well for the possibilities once the satellite passive microwave record is long enough to form a true climatic data base. 相似文献
18.
Andreas Nikolaidis Georgios C. Georgiou Diofantos Hadjimitsis Evangelos Akylas 《Central European Journal of Geosciences》2014,6(1):27-41
The Data Interpolating Empirical Orthogonal Functions method is a special technique based on Empirical Orthogonal Functions and developed to reconstruct missing data from satellite images, which is especially useful for filling in missing data from geophysical fields. Successful experiments in the Western Mediterranean encouraged extension of the application eastwards using a similar experimental implementation. The present study summarizes the experimental work done, the implementation of the method and its ability to reconstruct the sea-surface temperature fields over the Eastern Mediterranean basin, and specifically in the Levantine Sea. L3 type Satellite Sea-surface Temperature data has been used and reprocessed in order to recover missing information from cloudy images. Data reconstruction with this method proved to be extremely effective, even when using a relatively small number of time steps, and markedly accelerated the procedure. A detailed comparison with the two oceanographic models proves the accuracy of the method and the validity of the reconstructed fields. 相似文献
19.
大气科学优先资助领域的计量学初步分析 总被引：2，自引：0，他引：2
依据对国内大气科学相关机构进行广泛调研获取的数据，以及近期国内、国际有关大气科学期刊论文数据，通过计量学方法，按照国内基础、国内热点、国际热点和国内需求四个方面从不同角度对大气科学优先资助领域进行了分析，并根据不同政策偏好设置权重对大气科学各领域进行了排序。分析表明，不论是偏重于基础研究还是偏重于应用研究，优先资助人工影响天气和大气物理领域可能会获得更大的回报；若重视科学热点、科技前沿，优先资助气候系统与全球变化和天气动力学理论与天气预报领域可能会取得更多的研究成果；若重视发展需求与科技前沿相结合，优先资助大气化学和综合探测系统领域投入资金可能会发挥更大的效益。研究结果可以为更好地了解我国大气科学发展现状，制定大气科学中长期发展战略，制定大气科学“十一五”优先资助领域战略提供一定的参考依据。 相似文献
20.
AIRS红外高光谱资料反演大气水汽廓线研究进展 总被引：1，自引：0，他引：1
随着卫星遥感关键技术的突破,卫星光谱分辨率达到了分辨大气成分单个谱线的水平,研究人员开始了大量通道同时反演大气廓线和多种微量成分的研究.针对AIRS(Atmospheric Infrared Sounder)就红外高光谱资料反演大气水汽廓线的研究进展进行了评述,从训练数据、通道信息的提取及降维、反演算法和反演精度改进4个方面对反演晴空大气水汽廓线的研究现状进行了分析与讨论.AIRS资料反演大气水汽廓线的训练数据通常选用威斯康星大学提供的全球晴空反演训练样本集CIMSS (Cooperative Institute for Meteorological Satellite Studies,University of WisconsinMadison)和SARTA(Stand-Alone Radiative Transfer Algorithm)辐射传输模式模拟的亮温辐射值.归纳总结了2种通道信息的提取及降维方法:一是采用有效的方法来完成光谱信息压缩,对常用的主成分分析和独立分量分析方法进行了对比,认为独立分量分析更为可行.二是通道选择,即保留部分含有较多大气廓线信息量的通道,达到降维目的.在进行通道选择时要注意针对不同地区气候类型、下垫面、季节以及即时天气条件,选择不同的通道组合.介绍了3种反演算法:特征向量统计法、牛顿非线性迭代法和神经网络法.对比发现特征向量统计法简单易行,但精度不够理想;牛顿非线性迭代法精度虽高但计算耗时长,因此不适合业务使用;神经网络计算速度快、精度也能达到要求,具有很好的前景.对目前的几种样本分类方法及附加因子进行了对比分析,对反演算法精度的改进提出了一些有益的设想.最后对晴空辐射订正及云天大气水汽廓线反演进行了简要介绍,提出了该领域未来的一些研究方向. 相似文献