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1.
This paper explores applications of digital photogrammetric modeling of mountainous terrain in forecasting snow depth and the meltwater avalanche hazard in a mining region of northwestern Russia. A series of initial maps (initial terrain points, relief of snow-flow centers, slope angles and orientations) provides successively more specific information, culminating in the compilation of a map of maximum snow cover depths at a center of water-saturated snow flows (representative reference site) on the northern slope of Mt. Aykuayvenchorr. Translated by Edward Torrey, Alexandria, VA 22308 from: Geomorfologiya, 1993, No. 3, pp. 75-83.  相似文献   

2.
Snow cover mapping is important for snow and glacier-related research. The spatial and temporal distribution of snow cover area is a fundamental input to the atmospheric models, snowmelt runoff models and climate models, as well as other applications. Daily snow cover maps from Moderate Resolution Imaging Spectroradiometer (MODIS) Terra satellite were retrieved for the period between 2004 and 2007, and pixels in these images were classified as cloud, snow or snow-free. These images have then been compared with ground snow depth (SD) measurements from the four observatories located at different parts of Himalayas. Comparison of snow maps with in situ data showed good agreement with overall accuracies in between 78.15 and 95.60%. When snow cover was less, MODIS data were found to be less accurate in mapping snow cover region. As the SD increases, the accuracy of MODIS snow cover maps also increases.  相似文献   

3.
This study demonstrates the effectiveness of remote sensing and analytical hierarchy process for avalanche hazard mapping. The layers incorporated in this study were of slope, aspect, profile curvature, ground cover and elevation. The accuracy of output was determined using the registered avalanche sites based on ground observations and field-based modelling techniques. 93.35% of avalanche-affected areas came under maximum and moderate hazard zones, thus proving the effectiveness of this technique for Gangotri glacier basin. A parallel study was done to observe the change in the results, if any, by using high-resolution DEM and Cartosat-1 imagery. Similar methodology was adopted and the outcome was having significant improvement over the previous result as 98.8% of the preregistered avalanche area falling within maximum and moderate hazard zones.  相似文献   

4.
A method for determining areas of most intensive melting within a mountain snowpack is described, based on an inverse relationship between reflectance and age of snow at wavelengths greater than 0.8 μm. Comparisons between the area of snow cover detected on visible and near infrared satellite imagery at different times during the spring thaw, and more specifically differences in position of the snowline, permit identification of the upper boundary of a zone of intensive snow-melt and water discharge from the snow cover. Translated from: Distantsionnyye Issledovaniya rel'yefa Sibiri, A. L. Yanshin and V. N. Sharapov, eds. Novosibirsk: Nauka, 1985, pp. 88-91.  相似文献   

5.
The authors describe a methodology for the compilation of a final map from remote sensing imagery (that can be rapidly updated) showing the location of likely future sites of infestations of forest insect pests. A series of preliminary maps is compiled, with each stage of mapping providing information used in compiling a map in the subsequent stage, in this case wind damage $$ resistance to further damage $$ locations of potential centers of insect infestation. The design and informational content of maps at all stages in the process are described. Translated by Elliott B. Urdang, Providence, RI 02906 from: A. S. Isayev, V. I. Sukhikh, Ye. N. Kalashnikov et al., Aerokosmicheskiy monitoring lesov [Remote Sensing-Based Monitoring of Forests]. Moscow: Nauka, 1991, pp. 154-163.  相似文献   

6.
塔里木盆地周边地区泥石流灾害的遥感分析   总被引：1，自引：0，他引：1  
本文以MSS图像和TM图像为基本信息源,从影响泥石流灾害形成的自然要素,如地质（岩性、构造）、地形地貌、植被、水文（河流、冰川、雪被）、地面物质组成以及泥石流沟的遥感判读入手,结合气象资料分析,对塔里木盆地周边地区泥石流灾害的类型、分布状况、孕育和诱发条件进行探讨,进一步对该区泥石流灾害发育程度进行区划,并对危险区进行预测。  相似文献   

7.
The World Atlas of Snow and Ice Resources, scheduled for publication in the late 1980s, is an extensive cartographic summary of current knowledge about snow and ice. Roughly 750 maps organized under 17 broad themes cover topics such as glacier morphology, temperature and precipitation conditions in glacier formation, avalanches, meltwater runoff, sea ice, and past glaciation. The organization of the project is described along with the contents of major thematic sections, and examples of the use of basic initial maps to validate information used in more complex derivative maps are provided. Translated from: Materialy glyatsiologicheskikh issledovaniy, USSR Geophysical Committee Publication No. 51. Moscow: Mezhvedomstvenniy geofizicheskiy komitet, 1984, pp. 89-95.  相似文献   

8.
Avalanches are behind the majority of fatalities and heavy damage to property in snow-covered mountainous terrain like Himalaya. Recognizing avalanche susceptible areas and publication of avalanche susceptibility maps assist decision-makers and planners to execute suitable measures to reduce the avalanche risk. The present study is an attempt to prepare an avalanche susceptibility map of the Nubra valley region using multi-criteria decision analysis–analytical hierarchy process model in GIS environment. The most prominent avalanche occurrence factors used in this model are slope, aspect, curvature, elevation, terrain roughness and ground cover. ASTER GDEM V2 and Landsat 8 satellite imagery were used to generate considered factors. For validation of the results, prediction rate/accuracy is calculated using the avalanche inventory map of documented avalanche locations. To calculate the prediction accuracy, area under the ROC curve (ROC-AUC) method has been used. The prediction accuracy of the validation results using ROC-AUC shows 91%.  相似文献   

9.
A method for the compilation of 1:3,000,000-scale maps of natural nival-glacial phenomena is proposed for an area of the High Pamir Range in Soviet Central Asia. Such maps depict the distribution, frequency and intensity/magnitude, and potential impacts of such natural hazards as avalanches, mudslides, “dirty snow” avalanches (combined avalanches-mudslides in late spring), icings (naledy), and glacier pulsations, and are used in the planning of construction and the maintenance of roads and other transportation corridors during winter and spring. Hypothetical examples of the use of the maps are provided. Translated from: Materialy glyatsiologicheskikh issledovanly, USSR Geophysical Committee Publication No. 55. Moscow: Mezhduvedomstvenniy geofizicheskiy komitet, 1986, pp. 213–219.  相似文献   

10.
Snow avalanche studies require different snow-meteorological parameters for avalanche forecasting. Snow surface temperature is one of the major parameters, which is responsible for the evolution of snow pack characteristics. In the present paper, the snow surface temperature was estimated using TERRA satellite based — Moderate resolution imaging spectroradiometer (MODIS) sensor for NW-Himalayas. Ground data observed by automatic weather stations (AWS) was used to calibrate the brightness temperature obtained by MODIS thermal bands data into the actual snow surface temperature data through regression analysis. A split window technique has been implemented for the estimation of snow surface temperature. The multi-date satellite derived snow surface temperature was validated with ground data of winter 2004–05 and 2005–06 collected at various observation stations located in different ranges of NW-Himalaya. Good correlations were observed for Upper Himalaya (0.98, 0.98), Middle Himalaya (0.92, 0.96) and Lower Himalaya (0.88, 0.82) for 2004–05 and 2005–06 winter respectively. Further, estimated snow surface temperature was also verified with snow-cover information collected by manned observatories and area delineated by thematic maps of snow surface temperature was validated with the different snow climatic zones of NW-Himalaya.  相似文献   

11.
A study was conducted in south Texas to determine the feasibility of using airborne multispectral digital imagery for differentiating the invasive plant Brazilian pepper (Schinus terebinthifolius) from other cover types. Imagery obtained in the visible, near-infrared, and mid-infrared regions of the light spectrum and a supervised classification approach were employed to develop thematic maps of two areas infested with Brazilian pepper. Map accuracies ranged from 84.2 to 100% for the Brazilian pepper class. Findings support using airborne multispectral digital imagery as a tool for separating Brazilian pepper from associated land cover types and further encourage exploration of airborne multispectral digital imagery and image processing techniques for developing maps of Brazilian pepper infestation in Texas and abroad.  相似文献   

12.
Fault tectonics (i.e., frequency and intensity of faulting) is proposed as a leading factor governing the spatial distribution of exogenous processes which hinder construction activity (landslides, caveins, general subsidence, karst formation, etc.). This relationship provides the theoretical basis for compilation of engineering geomorphology maps which forecast the probability that such processes will occur in particular locations. Interpretation of space imagery at a variety of scales provides the raw date needed to test this relationship and compile the maps themselves. Sample maps prepared for river diversion and railroad construction projects are provided. Translated from: Geomorfologiya, 1984, No. 3, pp. 36-43.  相似文献   

13.
Principles and objectives governing Soviet thematic mapping of nearby planets are outlined, types of information sources for such mapping categorized, and the suitability of different types of information sources for thematic mapping are evaluated. This is followed by a classification of thematic planetary maps according to type. The need for a standardized, systems approach to the determination of map scales, compilation and generalization, symbolization, and map design is emphasized as an essential prerequisite for the development of complex atlases of individual planets, atlases of “comparative planetology,” and the establishment of “planetary information systems.” Translated by Jay Mitchell; PlanEcon, Inc.; Washington, DC 20005 from: Vestnik Moskovskogo Universiteta, geografiya, 1987, No. 6, pp. 60-67.  相似文献   

14.
A Russian geographer describes a methodology whereby data on slopes contained within a geographic information system are employed in the compilation of geomorphological maps. More specifically, the author proposes and tests a technology for the automated compilation of electronic maps of mean slope for the territory of Altay Kray, West Siberia, Russia. Translated by Edward Torrey, Alexandria, Virginia from: Geografiya i prirodnyye resursy, 2002, No. 2, pp. 142-146.  相似文献   

15.
This paper focuses on remote sensing's role in support of diverse mapping tasks, including those of interest to soil scientists (land use, soil, and botanical mapping). It analyzes new opportunities and challenges provided by remote sensing imagery with respect to map compilation and revision: the interdisciplinary yet goal-oriented character of map themes, the large stock of data to be processed systematically for coherent information yield, the numerous linkages of map elements to be represented on a series of closely interrelated maps, and the need for standardization and a unified approach to map design and symbolization. Translated by Edward Torrey, Alexandria, VA 22308 from: G. V. Dobrovol'skiy and V. L. Andronikov, eds., Aerokosmicheskiye metody v pochvo-vedenii i ikh ispol'zovaniye v sel'skom khozyaystve: sbornik nauchnykh trudov [Remote Sensing Methods in Soil Science and Their Utilization in Agriculture: A Collection of Scientific Works]. Moscow: Nauka, 1990, pp. 16-21.  相似文献   

16.
The Swiss Federal Institute for Snow and Avalanche Research in Davos (SLF) provides snow depth maps for Switzerland on a spatial resolution of 1 km × 1 km. These snow depth maps are derived from snow station measurements using a spatial interpolation method based on the dependency of snow depth and altitude. During a winter season the number of operating snow stations varies and the area-wide snow depth interpolation becomes increasingly difficult in spring. The objective of the study is to develop an operational and near-real time method to calculate snow depth maps using a combination of in situ snow depth measurements and the snow cover extent provided from space borne observations. The operational daily snow cover product obtained from the polar-orbiting NOAA-AVHRR satellite is used to gain an additional set of virtual snow stations to densify the in situ measurements for an improved spatial interpolation. The capacity of this method is demonstrated on selected days during winter 2005. Cross-validation tests are conducted to examine the quantitative accuracy of the synergetic interpolation method. The error estimators prove the decrease in error variance and increase of overall accuracy pointing out the high capacity of this new interpolation method that can be run in near real-time over a large horizontal domain at high horizontal resolution. A solid method for snow–no snow classification in the processing of the satellite data is essential to the quality of the snow depth maps.  相似文献   

17.
Specific criteria used in the compilation of large-scale maps of erosion-prone areas are defined and evaluated for tracts of land representing a number of different agricultural cover types. Formulas are derived which facilitate the mapping of such areas based on such readily observable morphometric characteristics as slope length and steepness. Translated by Edward Torrey, Alexandria, VA 22308 from: Vestnik Moskovskogo Universiteta, geografiya, 1988, No. 5, pp. 25-31.  相似文献   

18.
Materials derived from aerial and space surveys provided the basis for compilation of a series of geomorphological, geological, morphostructural, and lithodynamic maps as well as a map showing sources of manmade pollution. A derivative map of geoecological regions based on these maps makes it possible to estimate qualitatively the ecological state of any coastal region. The Buor-Khaya Gulf of the Laptev Sea is used as a test case. Translated by Edward Torrey, Alexandria, VA 22308 from: Geomorfologiya, 1995, No. 4, pp. 23-34.  相似文献   

19.
This study introduces a method for object-based land cover classification based solely on the analysis of LiDAR-derived information—i.e., without the use of conventional optical imagery such as aerial photography or multispectral imagery. The method focuses on the relative information content from height, intensity, and shape of features found in the scene. Eight object-based metrics were used to classify the terrain into land cover information: mean height, standard deviation (STDEV) of height, height homogeneity, height contrast, height entropy, height correlation, mean intensity, and compactness. Using machine-learning decision trees, these metrics yielded land cover classification accuracies > 90%. A sensitivity analysis found that mean intensity was the key metric for differentiating between the grass and road/parking lot classes. Mean height was also a contributing discriminator for distinguishing features with different height information, such as between the building and grass classes. The shape- or texture-based metrics did not significantly improve the land cover classifications. The most important three metrics (i.e., mean height, STDEV height, and mean intensity) were sufficient to achieve classification accuracies > 90%.  相似文献   

20.
Two general approaches for compiling maps of components of the water-ice budget in regions of glacier nourishment are compared and the resulting maps are analyzed. The compilation of raw data is based on field measurements rather than remote sensing information. Translated by Edward Torrey, Alexandria, VA 22308 from: Materialy glyatsiologicheskikh issledovaniy, 1991, No. 72, pp. 94-102.  相似文献   

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