多样地表和大气状况下的MODIS数据云检测

云覆盖作为天气和气候变化的一个重要因子,对地表-大气能量平衡和水循环有着重要的影响,因此,快速、准确地利用卫星遥感技术检测云覆盖具有重要的实用价值和科学意义。利用卫星遥感数据,尤其是常用的Moderate Resolution Imaging Spectroradiometer(MODIS)影像数据,因其具有较高的光谱和时间分辨率,以及2330 km扫描幅宽,为大范围实时、准确地进行云检测提供了可能。目前,基于MODIS数据发展了大量的云检测方法,但因地表类型的多样性和大气状况(如空气污染和沙尘事件等)的复杂性,目前已有的云检测方法,检测精度通常具有较大的不确定性,且针对不同地表和大气状况缺乏普适性,同时也缺乏对检测精度的定量化评估。因此,本文首先比较了常用的3种云检测算法,并基于前人经验提出了两种改进方法(方法4和方法5),首先区分出云和冰雹,摒弃了不稳定的亮温波段,两种算法均适用于复杂地表和大气状况的云检测算法。结果显示,方法5可以较好地应用于基于MODIS数据的云检测,总体精度达92.6±7%,改进了现有基于MODIS数据的云检测算法;方法4平均总体精度82.9±13%,虽然精度相对较低,但云残留少,适合作为对云敏感度高的研究工作的云检测方法。     

MONITORING ENVIRONMENTAL IMPACTS OF LENINGRAD ON THE SURROUNDING AREA

The author, a remote sensing specialist in Leningrad University's Department of Atmospheric Physics, describes the use of space imagery in a program for monitoring the city's impacts on the surrounding environment. The paper examines applications of LANDSAT and “Meteor” satellite imagery and “Soyuz-22” space photography in the study of industrial smoke plumes, jet contrails, atmospheric haze, albedo, the urban heat island, urban sprawl (including nighttime imagery), fallout of suspended particulates, and wastewater discharges into the Gulf of Finland. Translated from: Grigor'yev, A. A. Antropogennyye vozdeystviya na prirodnuyu sredy po nablyudeniyam iz kosmosa [Human Impacts on the Environment From Observations From Space]. Leningrad: Nauka, 1985, pp. 129-141 [Chapter 7].     

MAPPING THE STRUCTURE OF THE SOIL COVER OF THE TAIGA FROM REMOTE SENSING IMAGERY

An experiment is described in which multiscalar remote sensing imagery is sequentially employed in the detection of various rankings of soil types endemic to the taiga natural zone in the northern USSR. Relief features, vegetation associations, extent of surface water, and drainage patterns visible on imagery at scales from 1:12,000,000 to 1:5,000, also examined at low altitude and in the field at a series of test sites, served as indicators of various soil cover types. Considerable attention is given to an explanation of why these features can be considered valid indicators of taiga soil types as well as to the appearance of the indicators on band-specific (black-and-white) and color composite imagery. Translated from: Izvestiya Akademii Nauk SSSR, seriya geograficheskaya, 1987, No. 3, pp. 87-99.     

基于DEM的ETM+图像辐射校正及汉江流域反照率的计算

对Gilabert[1]大气校正方法进行改进,提出了一种简单易行的辐射校正方法。该方法只需从ETM⁺图像上获取两个不同海拔高程的暗像元,再依据DEM进行大气校正,反演出各个高程上的大气及辐射参数,并在此基础上进行地形校正,进而获取LandsatETM⁺1～5和7波段的地表反射率,通过对各窄波段地表反射率的线性组合获取反照率。结果表明,该方法可行,精度较高。     

以气象记录为辅助数据的TM影像大气校正方法

本文介绍一种LANDSATTM卫星影像校正方法,通过传感器校准、大气校正、地形校正等步骤获得反射率影像,卫星飞越时的大气参数是由当地气象记录的内插值导出,再以像幅内黑暗地物做调整,所用的大气传输模型为改进的Turner模型,可计算阳光直接辐照度、天光辐照度、路径亮度等参数,地形模型既可用来调整各参量随高程的变化,又可用以校正幅射的地形效应。     

多暗像元大气校正方法

 针对Landsat TM影像，设计了一种适用于非均质大气的大气校正方法。该方法以暗目标减法（DOS）为基础，结合大气辐射传输模型，通过选取TM影像上多个暗像元，并计算其所对应的大气校正系数对整幅图像进行大气校正。该方法不依赖任何外部信息，并且考虑了大气的非均质性，校正精度较高。     

USE OF SPACE IMAGERY IN THE STUDY OF MASS EXCHANGE IN GLACIER SYSTEMS

The author surveys the use of remote sensing imagery in the study of mass exchange in glaciers, i.e., glacier dynamics resulting from phase changes in the water which they contain. A program of research now underway at the Institute of Geography (USSR Academy of Sciences) in conjunction with the “Priroda” Remote Sensing Center (Moscow) focuses on improving methods of data collection and mapping of glacier dynamics from space imagery, and particularly on identifying natural glacioclimatic zones believed to represent specific mass exchange conditions or regimes. The boundary of glacier nourishment separating areas of accumulation and ablation represents a key glacioclimatic indicator of mass exchange on satellite imagery and aerial photography. Translated from: Geodeziya i kartografiya, 1986, No. 5, pp. 26–31.     

CBERS-02B星数据质量评价及其铀成矿要素解译应用研究

利用遥感影像处理技术和数理统计方法,评价了中巴地球资源一号卫星02B星（CBERS—02B,以下简称02B星）遥感数据的空间特性和辐射特征,并与ETM＋多光谱数据主要特征参数进行了对比分析。在此基础上,以江西桃山花岗岩型铀矿田为试验区,结合航空放射性数据,开展了基于02B星遥感数据的控矿断裂带、热液蚀变带及主要成矿岩体等铀成矿要素的光谱特征识别与提取,并对该数据的地学应用潜力进行了评价。     

一种基于阴影像元的光学遥感大气校正方法

提出一种基于6S模型 阴影像元的大气校正方法,适用于有阴影像元存在的高空间分辨率光学遥感影像。该方法从阴影像元与非阴影像元的信号差异估算气溶胶光学厚度,与暗目标方法相比,此方法避免地表反射率的假定难题。以北京市密云县的IKONOS影像对方法进行验证。在气溶胶光学厚度的估算上,该方法的估算结果与MODIS气溶胶产品基本一致,而且其结果的稳定性明显好于暗目标法。在大气校正的结果方面,针对各类地物,比较大气校正前后的光谱与同类典型实测地物光谱,结果说明大气校正能够大大恢复各类地物光谱的典型特征,这将有利于地物的识别。最后通过比较大气校正前后的NDVI发现,大气校正能够明显增大高植被覆盖区与低植被覆盖区NDVI的差别,使植被信息更加突出。     

REMOTE SENSING AND THE STUDY OF SIBERIAN MINERAL RESOURCES

The authors outline the general policy governing the use of remote sensing in Siberian mineral exploration—as a tool in the structural-geomorphologic mapping of potential mineral-bearing locations. Such maps are used to infer geologic structure (and endogenous conditions for mineral formation) and the character of contemporary exogenous processes (and conditions of transport and concentration of mineral residues) from geoindicators in surface terrain visible from space. Uses of space imagery in the study of seismic activity and engineering geomorphology are also described. Translated from: Kompleksnyye aerokosmicheskiye Issledovaniya Sibiri, A. L. Yanshin and L. K. Zyat'kova, eds. Novosibirsk: Nauka, 1984, pp. 5-14.     

THE USE OF ANCIENT MAPS AND SPACE IMAGERY IN THE STUDY OF ENVIRONMENTAL CHANGE

The author outlines, in diagrammatic form, a procedure for the joint use of old maps (topographic, land survey, etc.) and current space imagery to compile maps of environmental change. The ancient maps reveal land use and physical conditions which serve as a benchmark for evaluation of subsequent change. Space imagery is useful both in updating the current state of the environment and providing a cartographic base for the preparation of final maps. Selected areas of Moscow Oblast are used as test sites. Translated from: Izvestiya vuzov, Geodeziya i aerofotos' yem-ka, 1985, No. 1, pp. 104-109.     

TM/ETM+影像大气校正产品质量评价方法研究

对TM/ETM+的大气校正产品质量进行评价是改进影像质量的必要手段。提出采用已有高质量TM/ETM+表面反射率产品作为参考影像评价TM/ETM+的大气校正产品质量的方法。该方法设计了面向产品质量评价的影像光谱采样方案和多时相遥感影像PIFs(pseudo invariant features,PIFs)样本自动识别方法,能对多时相/季相TM/ETM+大气校正产品质量进行评价。试验表明该方法能准确识别PIFs地物,评价结果真实反映了遥感影像大气校正结果准确度。方法具有快速和低成本等特点,能开展规模化应用。     

APPLICATIONS OF REMOTE SENSING IN THE STUDY OF THE MOUNTAINOUS TERRAIN OF DAGESTAN

The authors explore a wide range of applications of remote sensing methods in the study of natural hazards posed by exogenous geomorphologic processes in areas of predominantly calcareous and shale-based rock in mountainous portions of Dagestan. Space imagery, air photographs, and ground truth established from field observations provides the basis for the mapping of environmental conditions with an emphasis on the extent to which mass movements and other exogenous geomorphologic processes pose natural hazards to human residence and economic activity. Translated by Elliott B. Urdang, Providence, RI 02906 from: Geomorfologiya, 1993, No. 4, pp. 26-35.     

THE COOLING OF THE EARTH BY CONVECTION AND SOME OF ITS CONSEQUENCES

Abstract

In this Review (24, 68, 1937) attention was drawn to the need, in considering isostasy, of recognizing the existence of two separate weak layers, i.e. layers in which material can flow horizontally. One of these is a deep layer under both oceans and continents, the other being a layer of plastic basalt, immediately under the continents only, in which mountain ranges and other local surface masses are compensated. That suggestion formed part of a wider theory which has been developed in recent articles in the Pan-American Geologist. A brief review of that theory may be of interest.     

CBERS-02B星数据质量评价及铀成矿要素解译应用研究

利用遥感影像处理技术和数理统计方法,评价了中巴地球资源卫星02B星(CBERS-02B,以下简称02B星)遥感数据的空间特性和辐射特征,并与ETM+多光谱数据主要特性参数进行了对比分析.在此基础上,以江西桃山花岗岩型铀矿田为试验区,结合航空放射性数据,开展了基于02B星遥感数据的控矿断裂带、热液蚀变带及主要成矿岩体等铀成矿要素的光谱特征识别与提取,并对该数据的地学应用潜力进行了评价.     

THE HISTORICAL GEOGRAPHY OF LANDSCAPES IN WESTERN IRAQ FROM SPACE IMAGERY

Space photography at 1:2,400,000 scale from the “Salyut-6” space station was used to compile maps on the evolution of arid landscapes in the Late Pleistocene and Holocene in western Iraq. The imagery made it possible to trace the development of many ancient natural features and to formulate an interpretation key of landscape elements—formed under a variety of past climatic environments, but subsequently evolving under common, somewhat similar natural conditions. This provides a basis for improved understanding the present state, history of formation, and future transformations of arid landscapes. Translated by Edward Torrey, Alexandria, VA 22308 from: Izvestiya Vsesoyuznogo Geograficheskogo Obshchestva, 1990, No. 3, pp. 255–260.     

AN INSTRUMENT-AIDED METHOD OF INTERPRETING SCANNER IMAGERY OF THE EARTH'S CLOUD COVER

The author, noting the high cost and complexity of automated methods of processing imagery of the earth's cloud cover, presents a less sophisticated, instrument-aided method yielding similar results. A procedure for analyzing cloud cover patterns based on color synthesis of two-band scanner imagery from Soviet “Meteor” and American NOAA-series weather satellites using a synthesizing projector is outlined. This method adds the interpretation key of color to those of cloud structure and form in the analysis of cloud patterns, enhances cloud-underlying surface contrasts, and compares favorably with more highly automated methods in image preparation and interpretation time. Translated by Jay Mitchell; PlanEcon, Inc.; Washington, DC 20005 from: Izvestiya vysshykh uchebnykh zavedeniy, Geodeziya i aerofotos'yemka, 1987, No. 5, pp. 95-98.     

IMAGE INTERPRETATION AS A SYSTEM OF SCIENTIFIC RESEARCH

The article provides insights derived from conceptualization of the totality of elements (subsystems) of image interpretation as part of a larger system of scientific research. Among the elements discussed in some detail in terms of their impacts on the appearance of features interpreted on remote sensing imagery include solar radiation, the atmosphere, distinctive characteristics of the surface of the area being imaged, the remote sensors employed for image recording, processing techniques, the image medium, and the “human” element (interpreter). It then describes an evolutionary process in image interpretation by which knowledge gained in early stages represents an input leading to refinement of approaches employed in later stages. A final section describes factors contributing to dynamics (“scintillation” or “flickering”) of features on imagery of the same area but recorded at different times or under different imaging conditions. Translated by Edward Torrey, Alexandria, VA 22308 from: Izvestiya Akademii Nauk, seriya geograficheskaya, 1993, No. 3, pp. 102-109.