遥感数据专题分类不确定性评价研究：进展、问题与展望

从遥感数据中提取专题类别信息是当前遥感数据最主要的应用领域之一。由于遥感分类专题信息广泛应用于各种领域，其数据质量受到越来越多的关注。不确定性是评价分类专题类别数据质量最主要的方面。回顾了遥感数据专题分类不确定性评价方法的历史，总结了当前各种评价方法及其指标体系，将这些方法归结为基于误差矩阵的方法、模糊评价方法、像元尺度上的不确定性评价方法和其它方法四大类。对每一类不确定性评价方法及其指标体系的优点和缺点进行了分析和总结，指出从理论方法研究方面，需要优先发展独立于分类方法的像元尺度上的遥感分类不确定性评价模型与指标体系，以及统一的遥感数据分类不确定性评价模型体系研究；在应用研究方面，需要加强优化空间采样设计和不确定性评价过程标准化研究。     

Development and Application of the Chinese Global Operational Oceanography Forecasting System

Chinese Global operational Oceanography Forecasting System (CGOFS) is configured in three levels of nested grids from global ocean, open ocean to offshore. This global operational oceanography forecasting system architecture is firstly bulit in China by the National Marine Environmental Forecasting Center (NMEFC). It has been put into operational forecasting at NMEFC, providing real-time forecasting of multi-scale ocean current, temperature, salinity, wave, sea surface wind, etc. All the ocean forecasting products are released in many ways and made available through the online, realizing full-range coverage in resolution from hundreds kilometer to several kilometer. The CGOFS includes 8 subsystems: global sea-surface wind numerical forecasting subsystem, global ocean circulation numerical forecasting subsystem, global ocean wave numerical forecasting subsystem, global tide and tidal current forecasting subsystem, Indian Ocean marine environment numerical forecasting subsystem, polar sea ice numerical forecasting subsystem, refined marine environment numerical forecasting for China’s surrounding waters,and integration management subsystem for operational support service of the CGOFS. Operational applications of the CGOFS are closely connected with China’s economic-social development and military security needs. For example, the CGOFS palys a crucial role in environmental forecasting for Chinese research vessel and icebreaker Xuelong, MH370 Searching, submersible “Jiaolong” exploration and nuclear contaminant transport from Fukushima Daiichi nuclear power plant, providing important scientific support for developing an ocean power, protecting national maritime rights, ensuring marine safety and coping with ocean problems in emergency.     

黑龙江省矿山地质灾害遥感调查研究

利用遥感技术综合不同平台类型、不同空间或光谱分辨率、不同时间频率的遥感数据,结合矿山地物目标特征,确定矿山地质灾害遥感解译标志.对矿山地质灾害现状、成因、分布规律等进行了分析评价.提供了客观、实时、动态的黑龙江省基础矿灾数据,为黑龙江省矿山地质灾害监督、管理、预警提供可靠地科学依据.     

Dynamic risk assessment of drought disaster for maize based on integrating multi-sources data in the region of the northwest of Liaoning Province, China

The traditional studies on drought disaster risk were based on the ground point data, which were unable to realize the continuity of space and the timeliness. It is shown that the monitoring and evaluation precision on drought were reduced significantly. However, remote sensing data in adequate spatial and temporal resolution can overcome these limitations. It can better monitor the crop in large area dynamically. This study presents a methodology for dynamic risk analysis and assessment of drought disaster to maize production in the northwest of Liaoning Province based on remote sensing data and GIS from the viewpoints of climatology, geography and disaster science. The model of dynamic risk assessment of drought disaster was established based on risk formation theory of natural disaster, and the expression of risk by integrating data came from sky, ground and space. The risk indexes were divided into four classes by data mining method, and the grade maps of drought disaster risk were drawn by GIS. It is shown that the spatial and temporal risk distributions of maize at each growth stage changed over time. The model has been verified against reduction in maize yield caused by drought. It demonstrated the reasonability, feasibility and reliability of the model and the methodology. The dynamic risk assessment of regional drought disaster for maize can be used as a tool, which can timely monitor the status (the possibility and extent of drought) and trends of regional drought disaster. The results obtained in this study can provide the latest information of regional drought disaster and the decision-making basis of disaster prevention and mitigation for government management and farmers.     

Comparative analysis of radioactive cesium wash-off from contaminated catchment areas after accidents at the Fukushima Dai-ichi and Chernobyl nuclear power plants

The paper presents quantitative data on radiocesium wash-off (dissolved and particulate) from catchment areas after the accident at the Fukushima-1 nuclear power plant. The evaluations are conducted based on published data on radiocesium monitoring in streams in the accident zone and monitoring at standard USLE plots. The characteristics of radiocesium wash-off and its distribution coefficient in riverine waters and surface runoff are analyzed by comparing data obtained on the territories of the Fukushima and Chernobyl accidents within a few years after the accidents. The normalized radiocesium wash-off coefficients in solution for the Fukushima river catchment area are one to two orders of magnitude lower than the analogous values for the Chernobyl catchment area. The normalized wash-off coefficients of radiocesium on particulate matter in the Fukushima and Chernobyl catchment areas are comparable. However, at least twice higher mean annual precipitation and steeper slopes in the Fukushima catchment area result in a higher annual wash-off coefficient than that of the Chernobyl area. It is demonstrated that characteristics of radiocesium wash-off obtained at USLE plots can be utilized to evaluate the scales of natural catchment areas.     

How can remote sensing contribute in groundwater modeling?

Groundwater resources assessment, modeling and management are hampered considerably by a lack of data, especially in semi-arid and arid environments with a weak observation infrastructure. Usually, only a limited number of point measurements are available, while groundwater models need spatial and temporal distributions of input and calibration data. If such data are not available, models cannot play their proper role in decision support as they are notoriously underdetermined and uncertain. Recent developments in remote sensing have opened new sources for distributed spatial data. As the relevant entities such as water fluxes, heads or transmissivities cannot be observed directly by remote sensing, ways have to be found to link the observable quantities to input data required by the model. An overview of the possibilities for employing remote-sensing observations in groundwater modeling is given, supported by examples in Botswana and China. The main possibilities are: (1) use of remote-sensing data to create some of the spatially distributed input parameter sets for a model, and (2) constraining of models during calibration by spatially distributed data derived from remote sensing. In both, models can be improved conceptually and quantitatively.     

内蒙古半干旱草原土壤植被大气相互作用(IMGRASS)综合研究

为深化对中纬半干旱草原气候生态相互作用过程、机制及其对全球变化的响应与贡献的认识 ,一项名为“内蒙古半干旱草原土壤植被大气相互作用 (IMGRASS)”的基金重大项目于 1997—2 0 0 1年在内蒙古锡林郭勒草原执行。IMGRASS计划在 1998年草原生长季节、在所选定的以典型草原为主 ,包括草甸草原、稀疏沙地草原等在内的中尺度试验区开展了多点、多要素的综合观测。观测内容包括土壤、植被、大气的相关要素和发生于地气界面的潜热、感热通量 ,还包括N2 O ,CH4 ,CO2 等微量气体交换量、辐射与降水分布。除 1998年中尺度观测试验外 ,在 1999— 2 0 0 1年在代表性地点进行了微量气体收支、遥感和沙尘天气相关的专项观测 ,结合草原站已进行的长期监测资料 ,分析气候生态长期相互作用 ,特别是人类活动干预的影响。在分析观测结果的基础上 ,对该地区的气候生态相互作用进行了数值模拟研究。文章作为介绍IMGRASS计划的第一部分 ,对该项研究计划作一全面简要介绍 ,包括科学目标、计划实施实验区背景、中尺度综合观测 ,并对实验所得大气边界层结构、辐射通量、沙地土壤水份状况、地表反射率谱与遥感测量等提供了个例分析 ,并简单介绍IMGRASS数据库。有关与全球变化有关的几个方面的初步研究结果将在本期刊中另文进行     

Coastal erosion hazard and vulnerability assessment for southern coastal Tamil Nadu of India by using remote sensing and GIS

The measurement and recording of the height and spatial extent reached by coastal storm surges is fundamental to scientific progress in understanding these phenomena. Such information is required for better prediction and for risk assessment. Model-based evaluation of increasing delta vulnerability, for example, cannot be tested without long-term, consistent, and sustained observation of actual events. Also, storm surges occur within the temporal context of tidal variation, which must first be characterized through observation. Present standard approaches for measuring storm surges are not optimum. Thus, tidal gauges provide information at one point, whereas the heights reached by surges vary spatially. Also, post-surge ground surveys are expensive, laborious, and commonly lack comparison to similar data obtained for previous surges or for high tides. The advent of moderate spatial resolution, high temporal resolution remote sensing initiated by the launch of the two NASA MODIS sensors greatly reduces these constraints. For over a decade, daily coverage of most coastal land areas, though restricted by cloud cover, has systematically captured the maximum extents reached by both high tides and by storm surges. Automated water classification algorithms are now transforming the incoming image data into GIS water boundary files, again at daily or near-daily time steps. This paper provides a retrospective view of sample storm surges as mapped via these sensors and describes: (a) the present, MODIS-based surface water surveillance system, (b) the mapping enhancement to be provided by frequent-repeat, wide-swath satellite radar imaging, and (c) the emerging prospects for routine global surveillance of storm surge events. Such will be necessary if long-term trends are to be recognized, characterized, and understood, along coastal zones now being affected by both increasing subsidence and rising sea level.     

Movement of radiocaesium fallout released by the 2011 Fukushima nuclear accident

The moment magnitude (M _w) 9.0 Tohoku-Oki Earthquake occurred on March 11, 2011, generating an unusually large tsunami. The seismic shocks and tsunami inundation severely damaged the Fukushima Daiichi Nuclear Power Plant. Radionuclide emission due to reactor breakdown contaminated wide areas of Fukushima and its surroundings. Heavy rainfall causes runoff across surface soil, and fine soil particles are susceptible to uptake by the flowing water. The high radioactivity of grains suspended in floodwater indicates that radioactive fallout was streamed into rivers in particulate form and transported downstream under high-flow conditions. Here, we investigated the diachronic mode of ¹³⁴Cs and ¹³⁷Cs in central Fukushima, through which the contaminated air mass drifted and caused wet deposition of radionuclides. Stratigraphic measurements of radioactivity in sediment cores is the method employed in this study to determine the basin-wide movement of ¹³⁴Cs and ¹³⁷Cs, to evaluate the significance of the erosion–transportation–accumulation processes on natural decontamination in terrain characterized by steep slopes and high precipitation. Stratigraphic results illustrate the process of fluvial sediment discharge, and the massive deposition of radiocaesium suggests basin-wide movement of fallout during concentrated rainfall. Grain suspension in torrential currents is an important pathway for transportation of radionuclides from land to sea, and the appearance of hotspots on floodplains and the offshore sea floor is the consequence of erosion and transportation under seasonal heavy precipitation. Radioactive horizons occur in offshore sediment columns and thus radiocaesium discharged from the estuary will persist forever under the sea floor if no artificial disturbance occurs.     

南极沿岸固定冰观测与研究述评

南极固定冰的变化能够直接反映南极的局地气候变率,因此是数值模式验证的理想载体,对固定冰的观测研究结论也能用于评估南极海冰的年际变化。现今国际上对南极固定冰的观测和研究日渐丰富和深入,并逐渐形成了由多个国家参加的联合观测网。就海冰厚度、冰芯结构、表面辐射收支等现场测量和相机、卫星等遥感观测方面,总结了目前国内外南极固定冰观测的技术手段和研究进展,并分析了不同空间尺度上的南极固定冰年际变化特征。对南极固定冰观测研究目前存在的问题和未来的发展方向进行了探讨。     

Spatial aspects of building and population exposure data and their implications for global earthquake exposure modeling

This paper discusses spatial aspects of the global exposure dataset and mapping needs for earthquake risk assessment. We discuss this in the context of development of a Global Exposure Database for the Global Earthquake Model (GED4GEM), which requires compilation of a multi-scale inventory of assets at risk, for example, buildings, populations, and economic exposure. After defining the relevant spatial and geographic scales of interest, different procedures are proposed to disaggregate coarse-resolution data, to map them, and if necessary to infer missing data by using proxies. We discuss the advantages and limitations of these methodologies and detail the potentials of utilizing remote-sensing data. The latter is used especially to homogenize an existing coarser dataset and, where possible, replace it with detailed information extracted from remote sensing using the built-up indicators for different environments. Present research shows that the spatial aspects of earthquake risk computation are tightly connected with the availability of datasets of the resolution necessary for producing sufficiently detailed exposure. The global exposure database designed by the GED4GEM project is able to manage datasets and queries of multiple spatial scales.     

基于遥感技术的三峡库区屏障带划分研究——以重庆市万州区为例

采用遥感技术和GIS空间分析相结合的方法,利用三期Landsat TM影像数据对重庆市万州区的地表亮温、地表湿度以及山脊线等特征对比分析,模拟其变化趋势和范围,通过多层数据叠加分析,划定出该区域的生态环境屏障带。结果表明,研究区中三峡水利工程对其生态环境影响有扩大的趋势;结合自然等综合因素,划定生态屏障带约为484.44 km2。研究结果有助于库区生态环境评价以及土地利用规划编制。     

月球表面温度物理模型研究现状

-总结了前人对月球表面温度的研究方法,对他们的研究进行了归类,分析了它们各自的优劣。直接测量和基于绕月飞行器的遥感测量均需投入昂贵的发射和维护费用,基于探测数据或月球样品分析数据的研究局限于某些时间段和地点,地基遥感探测的空间分辨率太低,这些方法自身的局限限制它们不可能用于全月的温度变化研究,只有通过建立比较完善的月球表面温度物理模型才可能达到这一目的。重点对月球表面温度物理模型进行讨论,分析了已有的模型,总结了影响月球表面温度的影响因素,包括月球表面太阳辐射、月球内部热流、月球表面物质的热吸收率、发射率、热导率、热容以及密度等,对这些因素的研究现状进行了概括,并提出了进一步研究这些参数的一些想法。     

卫星遥感监测我国沿海水色环境的研究

本文首先概要地介绍了国际上20世纪80年代以来卫星水色遥感器的发展,以及我国在90年代建立的海洋水色遥感应用技术系统,包括资料接收、处理、查询、分发、试应用和辐射验证等系统,重点论述了利用我国的FY-1C卫星以及美国的SeaWiFS和AVHRR卫星资料监测我国沿海的水色环境,包括沿海水体的叶绿素和悬浮泥砂浓度的时空分布,赤潮的监测以及沿海海区流场的研究。研究表明,卫星海洋水色遥感技术在海洋渔业资源的开发和保护、海岸带区牧化管理、河口港湾工程环境评价、海洋污染环境的监测和动力学研究等方面有广宽的应用前景。     

基于空间信息技术的地震灾害监测评估

空间信息技术即包括地理信息系统GIS、遥感RS、全球导航卫星系统GNSS以及数字地球在内的地球空间信息科学。随着计算机和空间对地观测技术的发展,空间信息技术已逐渐应用于防震减灾领域。本文通过实际震例分别对目前基于GIS、RS技术的地震灾害监测评估方法进行了分析研究,总结了其优越性以及存在的问题,并结合数字地球平台可视化展示了综合多源数据空间信息技术方法进行的震害评估效果。     

Ground-based optical measurements of daytime auroral emissions: A new means of investigating space-weather related processes

The first optical signatures of plasmapause associated processes were gleaned from the daytime auroral emissions monitored from Maitri, the Indian station in Antarctica, using the newly built, ground-based, Multiwavelength Daytime Photometer (MWDPM). The plasmapause boundary inferred from these measurements conforms well with the known empirical relationship with the geomagnetic indexKp. The measurements made at 391.4, 486.1, 557.7 and 630.0 nm emissions revealed significant day-to-day variations in their spatial and temporal extents. These preliminary results are presented and discussed.     

基于IHS变换的重力异常与遥感影像融合的构造信息提取研究

本文以深部探测关键仪器装备野外实验与示范基地为例,利用影像融合技术进行地质构造信息的提取。在卫星遥感和重力异常数据空间配准的基础上,利用IHS数据融合方法,将重力异常与ETM+数据进行融合与分析。研究表明:一方面构造形迹在遥感图像及重力异常上的表征是存在差异性的,即其空间分布特征,另一方面通过卫星遥感在地表定位重力异常所反演的地质信息,能够为深部探测仪器装备野外实验选点提供科学的依据。     

高光谱遥感水文地质应用新进展

高光谱遥感是一种利用成像光谱仪同时获取地物目标辐射、光谱和空间等多重信息遥感的技术,水文地质是高光谱遥感重要的应用领域之一,通过高光谱遥感图像分析,能够提取大区域包气带及含水系统的水文地质信息,可为水文地质环境的识别及实时监测、地下水资源高效管理、地下水数值模型构建等提供科学数据。通过调研凝练了高光谱遥感基本原理方法及其在水文地质方面的应用研究,重点总结了地下水环境污染和水文信息反演方面的高光谱遥感应用研究进展,分析了高光谱遥感水文地质应用所面临的挑战,并展望了高光谱遥感水文地质应用研究的发展趋势,主要包括:通过土壤和植被的光谱信息实现对研究区包气带土壤重金属污染状况的大面积、短周期连续快速监测;在高光谱图像中提取构造、地层岩性等地质和水文地质特征,以环境指示因子（如植被）为有效补充,获取饱和带地下水环境信息;通过高光谱图像识别植被类型、计算植被覆盖度、分析叶片反射光谱特征并建立模型反演土壤含水量和地下水位,为研究和保护缺水地区生态环境提供数据支撑。     

数字水文系统建设——信息时代的水文技术变革

在回顾２０世纪水文科学发民历程和分析当前面临的挑战和机遇的基础上,提出在数字化的信息时代,必须充分利用数字技术对传统水文进行全面的改革,建设数字水文系统,将站点观测的水文数据与数字地球中的有并数据,经过同化整合,产生数字化的、覆盖整个空间（流域或区域）的、多重尺度（时间和空间）的、多种要素的水文数据产品,为经济建设各有关部门和地球科学各个关领域服务。