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Геоинформационные технологии и космический мониторинг

Журнальные статьи

1.
Alamdar F., Kalantari M., Rajabifard A. An evaluation of integrating multisourced sensors for disaster management // Int. J. Digit. Earth. 2015. Vol. 8, № 9. P. 727–749.

Disaster management and in particular disaster response phase are highly time-sensitive and dynamic processes, demanding that real-time information reaches disaster responders prior making critical decisions. During the last decade, disaster management has been widely enabled through utilizing spatial data sourcing and related technologies in the whole process of collection, access, and usage of disaster information. Currently, there are unique challenges that cannot be met without incorporating in situ sensing as an emerging technology for sourcing and managing disaster information. These include (1) high temporal and spatial resolution of information, (2) broad range of disaster data, and (3) automated operations. Incorporating in situ sensing into the disaster management process can potentially address such challenges by providing data that support all of these requirements. Following an examination of current concepts and methods for integrating multisourced sensors, a framework of the requirements for integrating in situ sensors for disaster management, is suggested. Based on this framework and its components, an evaluation of the methods is developed and applied. The results highlight that information integration of multisourced sensors is a major challenge and has not yet adequately addressed for sensor data enablement of disaster management.

2.
Arvor D. et al. Advances in Geographic Object-Based Image Analysis with ontologies: A review of main contributions and limitations from a remote sensing perspective // Isprs Journal of Photogrammetry and Remote Sensing. 2013. Vol. 82. P. 125–137.

Geographic Object-Based Image Analysis (GEOBIA) represents the most innovative new trend for processing remote sensing images that has appeared during the last decade. However, its application is mainly based on expert knowledge, which consequently highlights important scientific issues with respect to the robustness of the methods applied in GEOBIA. In this paper, we argue that GEOBIA would benefit from another technical enhancement involving knowledge representation techniques such as ontologies. Although the role of ontologies in Geographical Information Sciences (GISciences) is not a new topic, few works have discussed how ontologies, considered from the perspective of a remote sensing specialist, can contribute to advancing remote sensing science. We summarize the main applications of ontologies in GEOBIA, especially for data discovery, automatic image interpretation, data interoperability, workflow management and data publication. Finally, we discuss the major issues related to the construction of ontologies suitable for remote sensing applications and outline long-term future advances that can be expected for the remote sensing community.

3.U21083
Barnosky A.D. et al. Approaching a state shift in Earth’s biosphere // Nature. 2012. Vol. 486, № 7401. P. 52–58.

Localized ecological systems are known to shift abruptly and irreversibly from one state to another when they are forced across critical thresholds. Here we review evidence that the global ecosystem as a whole can react in the same way and is approaching a planetary-scale critical transition as a result of human influence. The plausibility of a planetary-scale 'tipping point' highlights the need to improve biological forecasting by detecting early warning signs of critical transitions on global as well as local scales, and by detecting feedbacks that promote such transitions. It is also necessary to address root causes of how humans are forcing biological changes.

4.
Beck I. et al. Assessing Permafrost Degradation and Land Cover Changes (1986-2009) using Remote Sensing Data over Umiujaq, Sub-Arctic Quebec // Permafrost and Periglacial Processes. 2015. Vol. 26, № 2. P. 129–141.

Recent land cover changes in the Umiujaq region of northern Quebec, Canada, have been quantified in order to estimate changes in the extent of discontinuous permafrost that strongly affect the forest-tundra ecotone. Changes in the areas covered by different vegetation types, thermokarst lakes and degradation of lithalsas have been investigated over an area of 60 km(2), extending from widespread discontinuous permafrost in the north to areas of scattered permafrost in the south, and from Hudson Bay in the west to the Lac Guillaume-Delisle graben 10 km further east. We used high-resolution remote sensing images (QuickBird 2004, GeoEye 2009) and four Landsat scenes (1986, 1990, 2001, 2008) as well as ground-based data (vegetation, active layer thickness, snow parameters) collected between 2009 and 2011. Two change detection methods applied to estimate the land cover changes between 1986 and 2009 showed an overall increase in vegetation extent between 1986 and 2009, and a 21 per cent increase in tall vegetation (spruce and tall shrubs) between 2004 and 2009 at the expense of low vegetation (lichens, prostrate shrubs, herbaceous vegetation). Thermokarst lakes and lithalsas in ten sub-areas were mapped manually from satellite imagery. The area covered by water decreased by 24 per cent between 2004 and 2009, often due to vegetation colonising the margins of lakes, and 93 of the observed lakes disappeared completely over that period. The area covered by lithalsas declined by 6 per cent. Our results demonstrate the viability of using high-resolution satellite imagery to detect changes in the land surface that can serve as indicators of permafrost degradation in the sub-Arctic.

5.U21083
Brumfiel G. Europe loses sight of Earth // Nature. 2012. Vol. 484, № 7395. P. 423–424.

With hopes fading fast for the crippled Earth-observing satellite Envisat, researchers are warning that delays to its replacements will leave Europe lacking vital monitoring data for years to come.Launched in 2002, Envisat is the largest environmental satellite ever built and the mainstay of the Earth-observing programme for the European Space Agency (ESA). The 8.2-tonne satellite has 10 instruments with which to take the planet’s pulse, including radars, infrared and optical imagers, and spectrometers.

6.U60656
Chen J., Xiang L.G., Gong J.Y. Virtual globe-based integration and sharing service method of GeoSpatial Information // Science China Earth Sciences. 2013. Vol. 56, № 10. P. 1780–1790.

How to integrate and disseminate globally distributed multi-source and heterogeneous spatial information is an open problem in integration and sharing service of geographic information. Here we propose a new service architecture suitable for integration and sharing of distributed multi-source geographic information. We also propose a global virtual pyramid model, which can be applied in 3D virtual globes. In view of the difficulty of web multi-node geographic information sharing service, we propose a web multi-node service aggregation method, integrated in our autonomously developed virtual globe platform Geo-Globe and introduced in the National Platform for Common GeoSpatial Information Services named "TIANDITU". It achieves 2D and 3D integration for geographic information service.

7.
Chen N. et al. Progress and challenges in the architecture and service pattern of Earth Observation Sensor Web for Digital Earth // Int. J. Digit. Earth. 2014. Vol. 7, № 12. P. 935–951.

The Earth Observation (EO) Web is the data acquisition and processing network for digital Earth. The EO Web including Data Web and Sensor Web has become one of the most important aspects of the Digital Earth 2020. This paper summarised the history of the development and status quo of the major types of EO data web service systems, including architecture, service pattern and standards. The concepts, development and implementation of the EO Sensor Web were reviewed. Furthermore, we analysed the requirements on the architecture of the next-generation EO Sensor Web system, namely Spaceborne-Airborne-Ground integrated Intelligent EO Sensor Web system, and highlighted the virtualization, intelligent, pervasive and active development tendency of such system.

8.
Chen N., Zhou L., Chen Z. A Sharable and Efficient Metadata Model for Heterogeneous Earth Observation Data Retrieval in Multi-Scale Flood Mapping // Remote Sens. 2015. Vol. 7, № 8. P. 9610–9631.

Remote sensing plays an important role in flood mapping and is helping advance flood monitoring and management. Multi-scale flood mapping is necessary for dividing floods into several stages for comprehensive management. However, existing data systems are typically heterogeneous owing to the use of different access protocols and archiving metadata models. In this paper, we proposed a sharable and efficient metadata model (APEOPM) for constructing an Earth observation (EO) data system to retrieve remote sensing data for flood mapping. The proposed model contains two sub-models, an access protocol model and an enhanced encoding model. The access protocol model helps unify heterogeneous access protocols and can achieve intelligent access via a semantic enhancement method. The enhanced encoding model helps unify a heterogeneous archiving metadata model. Wuhan city, one of the most important cities in the Yangtze River Economic Belt in China, is selected as a study area for testing the retrieval of heterogeneous EO data and flood mapping. The past torrential rain period from 25 March 2015 to 10 April 2015 is chosen as the temporal range in this study. To aid in comprehensive management, mapping is conducted at different spatial and temporal scales. In addition, the efficiency of data retrieval is analyzed, and validation between the flood maps and actual precipitation was conducted. The results show that the flood map coincided with the actual precipitation.

9.
Chen Z., Chen N. Provenance Information Representation and Tracking for Remote Sensing Observations in a Sensor Web Enabled Environment // Remote Sens. 2015. Vol. 7, № 6. P. 7646–7670.

The provenance of observations from a Sensor Web enabled remote sensing application represents a great challenge. There are currently no representations or tracking methods. We propose a provenance method that represents and tracks remote sensing observations in the Sensor Web enabled environment. The representation can be divided into the description model, encoding method, and service implementation. The description model uses a tuple to define four objects (sensor, data, processing, and service) and their relationships at a time point or interval. The encoding method incorporates the description into the Observations & Measurements specification of the Sensor Web. The service implementation addresses the effects of the encoding method on the implementation of Sensor Web services. The tracking method abstracts a common provenance algorithm and four algorithms that track the four objects (sensor, data, processing, and service) in a remote sensing observation application based on the representation. We conducted an experiment on the representation and tracking of provenance information for vegetation condition products, such as the Normalized Difference Vegetation Index (NDVI) and the Vegetation Condition Index (VCI). Our experiments used raw Moderate Resolution Imaging Spectroradiometer (MODIS) data to produce daily NDVI, weekly NDVI, and weekly VCI for the 48 contiguous states of the United States, for May from 2000 to 2012. We also implemented inverse tracking. We evaluated the time and space requirements of the proposed method in this scenario. Our results show that this technique provides a solution for determining provenance information in remote sensing observations.

10.U47933
Chiang S.-H., Chang K.-T. Application of radar data to modeling rainfall-induced landslides // Geomorphology. 2009. Vol. 103, № 3. P. 299–309.

Many shallow landslides are triggered by heavy rainfall. Previous studies of landslide modeling have been hampered by the scarcity of rain gauges to adequately depict the spatial variability of rainfall conditions triggering landslides. This study simulates the efficiency of the critical rainfall model for landslide prediction in a mountainous watershed with inputs of different rainfall estimates associated with a typhoon (tropical cyclone) event. Doppler radar data at a spatial resolution of 1 km and measurements from six gauging stations provide the sources for rainfall estimates. Inverse distance weighted, splines, and kriging are the interpolation methods for gauged rainfall estimates. A comparison of the simulation outputs shows that the model using radar rainfall estimates has a better performance than those using gauged rainfall estimates in predicting both landslides and stable areas. In light of the results, this paper also discusses the validity of the critical rainfall model for landslides in relation to its rainfall input and steady-state hydrological assumption.

11.
Demir B., Bruzzone L. A Novel Active Learning Method in Relevance Feedback for Content-Based Remote Sensing Image Retrieval // Ieee Transactions on Geoscience and Remote Sensing. 2015. Vol. 53, № 5. P. 2323–2334.

Conventional relevance feedback (RF) schemes improve the performance of content-based image retrieval (CBIR) requiring the user to annotate a large number of images. To reduce the labeling effort of the user, this paper presents a novel active learning (AL) method to drive RF for retrieving remote sensing images from large archives in the framework of the support vector machine classifier. The proposed AL method is specifically designed for CBIR and defines an effective and as small as possible set of relevant and irrelevant images with regard to a general query image by jointly evaluating three criteria: 1) uncertainty; 2) diversity; and 3) density of images in the archive. The uncertainty and diversity criteria aim at selecting the most informative images in the archive, whereas the density criterion goal is to choose the images that are representative of the underlying distribution of data in the archive. The proposed AL method assesses jointly the three criteria based on two successive steps. In the first step, the most uncertain (i.e., ambiguous) images are selected from the archive on the basis of the margin sampling strategy. In the second step, the images that are both diverse (i.e., distant) to each other and associated to the high-density regions of the image feature space in the archive are chosen from the most uncertain images. This step is achieved by a novel clustering-based strategy. The proposed AL method for driving the RF contributes to mitigate problems of unbalanced and biased set of relevant and irrelevant images. Experimental results show the effectiveness of the proposed AL method.

12.
Fang S. et al. An integrated system for regional environmental monitoring and management based on internet of things // IEEE Transactions on Industrial Informatics. 2014. Vol. 10, № 2. P. 1596–1605.

Climate change and environmental monitoring and management have received much attention recently, and an integrated information system (IIS) is considered highly valuable. This paper introduces a novel IIS that combines Internet of Things (IoT), Cloud Computing, Geoinformatics [remote sensing (RS), geographical information system (GIS), and global positioning system (GPS)], and e-Science for environmental monitoring and management, with a case study on regional climate change and its ecological effects. Multi-sensors and web services were used to collect data and other information for the perception layer; both public networks and private networks were used to access and transport mass data and other information in the network layer. The key technologies and tools include real-time operational database (RODB); extraction-transformation-loading (ETL); on-line analytical processing (OLAP) and relational OLAP (ROLAP); naming, addressing, and profile server (NAPS); application gateway (AG); application software for different platforms and tasks (APPs); IoT application infrastructure (IoT-AI); GIS and e-Science platforms; and representational state transfer/Java database connectivity (RESTful/JDBC). Application Program Interfaces (APIs) were implemented in the middleware layer of the IIS. The application layer provides the functions of storing, organizing, processing, and sharing of data and other information, as well as the functions of applications in environmental monitoring and management. The results from the case study show that there is a visible increasing trend of the air temperature in Xinjiang over the last 50 years (1962-2011) and an apparent increasing trend of the precipitation since the early 1980s. Furthermore, from the correlation between ecological indicators [gross primary production (GPP), net primary production (NPP), and leaf area index (LAI)] and meteorological elements (air temperature and precipitation), water resource availability is the decisive factor with regard to the terrestrial ecosystem in the area. The study shows that the research work is greatly benefited from such an IIS, not only in data collection supported by IoT, but also in Web services and applications based on cloud computing and e-Science platforms, and the effectiveness of monitoring processes and decision-making can be obviously improved. This paper provides a prototype IIS for environmental monitoring and management, and it also provides a new paradigm for the future research and practice; especially in the era of big data and IoT.

13.
Ferreira K.R., Camara G., Monteiro A.M.V. An Algebra for Spatiotemporal Data: From Observations to Events // Transactions in GIS. 2014. Vol. 18, № 2. P. 253–269.

Recent technological advances in geospatial data gathering have created massive data sets with better spatial and temporal resolution than ever before. These large spatiotemporal data sets have motivated a challenge for Geoinformatics: how to model changes and design good quality software. Many existing spatiotemporal data models represent how objects and fields evolve over time. However, to properly capture changes, it is also necessary to describe events. As a contribution to this research, this article presents an algebra for spatiotemporal data. Algebras give formal specifications at a high-level abstraction, independently of programming languages. This helps to develop reliable and expressive applications. Our algebra specifies three data types as generic abstractions built on real-world observations: time series, trajectory and coverage. Based on these abstractions, it defines object and event types. The proposed data types and functions can model and capture changes in a large range of applications, including location-based services, environmental monitoring, public health, and natural disasters.

14.U46625
Forbes J.M., Moudden Y. Quasi-two-day wave-tide interactions as revealed in satellite observations // Journal of Geophysical Research-Atmospheres. 2012. Vol. 117. P. D12110.

In this paper we demonstrate how observations from Sun-synchronous and quasi-Sun-synchronous satellites can be analyzed to reveal the signatures of nonlinear interactions between tides and planetary waves in Earth's mesosphere and lower thermosphere. This is done by ordering data in longitude space, and demonstrating how peaks in the spectra of such data series can be identified with specific waves or combinations of waves. We use as an example the quasi-two-day wave (QTDW) oscillations in temperature observed by the Microwave Limb Sounder (MLS) instrument on the Aura satellite and the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) on the TIMED satellite. We show that the QTDW not only produces secondary waves due to nonlinear interactions with the migrating (Sun-synchronous) diurnal and semidiurnal tides, but that secondary waves are also produced by nonmigrating tide-QTDW interactions. Moreover, these latter secondary waves are of similar amplitude to the resident tides and the QTDW, and serve an important role in defining longitude structures due to the presence of these waves.

15.U47933
Ghoneim E.M. Ibn-Batutah: A possible simple impact structure in southeastern Libya, a remote sensing study // Geomorphology. 2009. Vol. 103, № 3. P. 341–350.

The Ibn-Batutah feature is a circular structure centered on 21°34?10? N and 20°50?15? E and located in the prefecture of the Hamadat Ibn-Batutah plateau, southeastern Libya. It is a singular geological structure formed in Nubian Sandstone of most likely early Cretaceous age. Remote sensing investigations based on Landsat ETM+, dual-band (L and C) and dual-polarization (HH and HV) radar (SIR-C), and SRTM data reveal a morphological resemblance of the Ibn-Batuta structure to other confirmed terrestrial simple impact structures. The structure is in the form of a circular basin 2.5 km in diameter and ~ 25 m deep, surrounded by a low-relief rim that rises to within 5 m of the surrounding terrains over much of its extent. No endogenic geological processes such as magmatism, diapirism, karst dissolution, and glacial or fluvial erosion can decisively explain the formation of the Ibn-Batutah structure within a large area of flat-lying Mesozoic sandstones. Thus, this paper proposes that the Ibn-Batutah structure represents a simple impact structure. Verification of this hypothesis will require collection and analyses of rock samples from in and around the structure, although the area is currently almost inaccessible for environmental and security reasons.

16.U60656
Guo H.D. et al. Conceptual study of lunar-based SAR for global change monitoring // Science China Earth Sciences. 2014. Vol. 57, № 8. P. 1771–1779.

As an active microwave remote sensing imaging sensor, Synthetic Aperture Radar (SAR) plays an important role in earth observation. Here we establish a SAR system based on the platform of the moon. This will aid large-scale, constant, and long-term dynamic Earth observations to better meet the needs of global change research and to complement the space borne and airborne earth observations. Lunar-based SAR systems have the characteristics of high resolution and wide swath width. The swath width could be thousands of kilometers in the stripe mode and it could cover 40% of earth's surface with 10 meters or even higher spatial resolution in the scanning mode. Using the simplified observation model, here we quantitatively analyze the spatial resolution and coverage area of lunar-based SAR and simulate the observation on the Qinghai-Tibet plateau and the Amazon plain. The results show that this system could provide near 100% daily coverage of the Qinghai-Tibet plateau, whereas 40% to 70% daily coverage of the Amazon plain. Lunar-based SAR could provide large-scale, long-term and stable time series data in order to support future research of global change.

17.U37081
Hopkinson C., Chasmer L. Testing LiDAR models of fractional cover across multiple forest ecozones // Remote Sensing of Environment. 2009. Vol. 113, № 1. P. 275–288.

Four LiDAR-based models of canopy fractional cover (FCLiDAR) have been tested against hemispherical photography fractional cover measurements (FCHP) and compared across five ecozones, eight forest species and multiple LiDAR survey configurations. The four models compared are based on: i) a canopy-to-total first returns ratio (FCLiDAR(FR)) method; ii) a canopy-to-total returns ratio (FCLiDAR(RR)); iii) an intensity return ratio (FCLiDAR(IR)); and iv) a Beer's Law modified (two-way transmission loss) intensity return ratio (FCLiDAR(BL)). It is found that for the entire dataset, the FCLiDAR(RR) model demonstrates the lowest overall predictive capability of overhead FC (annulus rings 1–4) (r2 = 0.70), with a slight improvement for the FCLiDAR(FR) model (r2 = 0.74). The intensity-based FCLiDAR(IR) model displays the best results (r2 = 0.78). However, the FCLiDAR(BL) model is considered generally more useful (r2 = 0.75) because the associated line of best fit passes through the origin, has a slope near unity and produces a mean estimate of FCHP within 5%. Therefore, FCLiDAR(BL) requires the least calibration across a broad range of forest cover types. The FCLiDAR(FR) and FCLiDAR(RR) models, on the other hand, were found to be sensitive to variations in both canopy height and sensor pulse repetition frequency (or pulse power); i.e. changing the repetition frequency led to a systematic shift of up to 11% in the mean FCLiDAR(RR) estimates while it had no effect on the intensity-based FCLiDAR(IR) or FCLiDAR(BL) models. While the intensity-based models were generally more robust, all four models displayed at least some sensitivity to variations in canopy structural class, suggesting that some calibration of FCLiDAR might be necessary regardless of the model used. Short (< 2 m tall) or open canopy forest plots posed the greatest challenge to accurate FC estimation regardless of the model used.

18.
Hu C. et al. An Object Model for Integrating Diverse Remote Sensing Satellite Sensors: A Case Study of Union Operation // Remote Sens. 2014. Vol. 6, № 1. P. 677–699.

In the Earth Observation sensor web environment, the rapid, accurate, and unified discovery of diverse remote sensing satellite sensors, and their association to yield an integrated solution for a comprehensive response to specific emergency tasks pose considerable challenges. In this study, we propose a remote sensing satellite sensor object model, based on the object-oriented paradigm and the Open Geospatial Consortium Sensor Model Language. The proposed model comprises a set of sensor resource objects. Each object consists of identification, state of resource attribute, and resource method. We implement the proposed attribute state description by applying it to different remote sensors. A real application, involving the observation of floods at the Yangtze River in China, is undertaken. Results indicate that the sensor inquirer can accurately discover qualified satellite sensors in an accurate and unified manner. By implementing the proposed union operation among the retrieved sensors, the inquirer can further determine how the selected sensors can collaboratively complete a specific observation requirement. Therefore, the proposed model provides a reliable foundation for sharing and integrating multiple remote sensing satellite sensors and their observations.

19.
Hu C., Chen N., Li J. Geospatial Web-based Sensor Information Model for Integrating Satellite Observation: An Example in The Field of Flood Disaster Management // Photogramm. Eng. Remote Sens. 2013. Vol. 79, № 10. P. 915–927.

Flood observation-supporting satellite sensors (FO-SSs) are the important geospatial resources to flood disaster management. In the geospatial sensor Web environment, effective flood disaster management requires on-demand integration of instant observation information from the diverse web-ready FO-SSs. We propose a sharable and interoperable Earth Observation Satellite Sensor Information (SSI) model for satellite observations integration. The SSI model reuses and extends the existing metadata standards to be a standard metadata-filled description framework. The SensorModel prototype serving here is to apply the SSI model into FO-SSs, retrieve and visualize the qualified Web-ready FO-SSs. An experiment on the flood emergency in the middle reaches of Yangtze River basin in China is conducted. The results show that, three kinds of users including FO-SSs providers, common emergency responders, and emergency managers can benefit from the proposed FO-SSI model, and the managers can reliably and comprehensively integrate the satisfied Web-ready FO-SSs to guide the scheduling of the required observation activities.

20.U60656
Hu L.Y. et al. A 30 meter land cover mapping of China with an efficient clustering algorithm CBEST // Science China Earth Sciences. 2014. Vol. 57, № 10. P. 2293–2304.

Remote sensing based land cover mapping at large scale is time consuming when using either supervised or unsupervised classification approaches. This article used a fast clustering method—Clustering by Eigen Space Transformation (CBEST) to produce a land cover map for China. Firstly, 508 Landsat TM scenes were collected and processed. Then, TM images were clustered by combining CBEST and K-means in each pre-defined ecological zone (50 in total for China). Finally, the obtained clusters were visually interpreted as land cover types to complete a land cover map. Accuracy evaluation using 2159 test samples indicates an overall accuracy of 71.7% and a Kappa coefficient of 0.64. Comparisons with two global land cover products (i.e., Finer Resolution Observation and Monitoring of Global Land Cover (FROM-GLC) and GlobCover 2009) also indicate that our land cover result using CBEST is superior in both land cover area estimation and visual effect for different land cover types.

21.U37081
Immerzeel W.W. et al. Large-scale monitoring of snow cover and runoff simulation in Himalayan river basins using remote sensing // Remote Sensing of Environment. 2009. Vol. 113, № 1. P. 40–49.

Various remote sensing products are used to identify spatial–temporal trends in snow cover in river basins originating in the Himalayas and adjacent Tibetan–Qinghai plateau. It is shown that remote sensing allows detection of spatial–temporal patterns of snow cover across large areas in inaccessible terrain, providing useful information on a critical component of the hydrological cycle. Results show large variation in snow cover between years while an increasing trend from west to east is observed. Of all river basins the Indus basin is, for its water resources, most dependent on snow and ice melt and large parts are snow covered for prolonged periods of the year. A significant negative winter snow cover trend was identified for the upper Indus basin. For this basin a hydrological model is used and forced with remotely sensed derived precipitation and snow cover. The model is calibrated using daily discharges from 2000 to 2005 and stream flow in the upper Indus basin can be predicted with a high degree of accuracy. From the analysis it is concluded that there are indications that regional warming is affecting the hydrology of the upper Indus basin due to accelerated glacial melting during the simulation period. This warming may be associated with global changes in air temperature resulting from anthropogenic forcings. This conclusion is primarily based on the observation that the average annual precipitation over a five year period is less than the observed stream flow and supported by positive temperature trends in all seasons.

22.
Jimenez M. et al. Field Spectroscopy Metadata System Based on ISO and OGC Standards // ISPRS Int. Geo-Inf. 2014. Vol. 3, № 3. P. 1003–1022.

Field spectroscopy has undergone a remarkable growth over the past two decades in terms of use and application to different scientific disciplines. This work presents an important step forward to improve the interoperability for the spectral library interchange in the field spectroscopy scientific community, by establishing an XML-based metadata system using published International Organization for Standardization (ISO) standards and Open Geospatial Consortium (OGC) specifications. The proposed methodology is structured using three different XML files: each spectral library file acquired during a field campaign is accompanied by an XML file encoded according to the ISO 19156 standard, which carries the information related to the material or surface measured and the sampling procedure applied; the spectral libraries acquired on the same date share an XML file encoded according to the ISO 19115 standard, to represent dataset-level metadata; finally, all of the spectral libraries for the entire field campaign are referenced to an XML file encoded according to the Sensor Model Language (SensorML) specification, for information related to the field spectrometer characteristics and status. This structure ensures that the ISO 19156 files are not very large and avoids the repetition of many common metadata elements required to describe the dataset and sensor description.

23.
Li D., Gong J., Yue P. Geoinformatics education in China // Geo-Spatial Information Science. 2014. Vol. 17, № 4. P. 208–218.

The paper gives an overview of the current status of education in geoinformatics in China. First, the paper provides a brief introduction to the history of geoinformatics education in China and a general review of the scientific and technological development. It then presents how the development affects the education and training in China. In the paper, universities and institutes in China that can award academic degrees related to geoinformatics are summarized, and undergraduate majors are briefly introduced. Next, the paper reports the work having been done by the national expert group on Surveying and Mapping, including the revision of discipline catalog and guide for graduate education and requirements. A list of typical curricula in geoinformatics education is suggested. Activities on promoting the graduate student exchange platform are presented. Finally, a case study of geoinformatics education in Wuhan University is discussed.

24.U60656
Li D.R. et al. Current issues in high-resolution earth observation technology // Science China Earth Sciences. 2012. Vol. 55, № 7. P. 1043–1051.

This paper reviewed the developments of the last ten years in the field of international high-resolution earth observation, and introduced the developmental status and plans for China's high-resolution earth observation program. In addition, this paper expounded the transformation mechanism and procedure from earth observation data to geospatial information and geographical knowledge, and examined the key scientific and technological issues, including earth observation networks, high-precision image positioning, image understanding, automatic spatial information extraction, and focus services. These analyses provide a new impetus for pushing the application of China's high-resolution earth observation system from a "quantity" to "quality" change, from China to the world, from providing products to providing online service.

25.U60656
Li F. et al. Remote sensing based monitoring of interannual variations in vegetation activity in China from 1982 to 2009 // Science China Earth Sciences. 2014. Vol. 57, № 8. P. 1800–1806.

Terrestrial vegetation is one of the most important components of the Earth's land surface. Variations in terrestrial vegetation directly impact the Earth system's balance of material and energy. This paper describes detected variations in vegetation activity at a national scale for China based on nearly 30 years of remote sensing data derived from NOAA/AVHRR (1982-2006) and MODIS (2001-2009). Vegetation activity is analyzed for four regions covering agriculture, forests, grasslands, and China's Northwest region with sparse vegetation cover (including regions without vegetation). Relationships between variations in vegetation activity and climate change as well as agricultural production are also explored. The results show that vegetation activity has generally increased across large areas, especially during the most recent decade. The variations in vegetation activity have been driven primarily by human factors, especially in the southern forest region and the Northwest region with sparse vegetation cover. The results further show that the variations in vegetation activity have influenced agricultural production, but with a certain time lag.

26.U60656
Li X. Characterization, controlling, and reduction of uncertainties in the modeling and observation of land-surface systems // Science China Earth Sciences. 2014. Vol. 57, № 1. P. 80–87.

Uncertainty is one of the greatest challenges in the quantitative understanding of land-surface systems. This paper discusses the sources of uncertainty in land-surface systems and the possible means to reduce and control this uncertainty. From the perspective of model simulation, the primary source of uncertainty is the high heterogeneity of parameters, state variables, and near-surface atmospheric states. From the perspective of observation, we first utilize the concept of representativeness error to unify the errors caused by scale representativeness. The representativeness error also originates mainly from spatial heterogeneity. With the aim of controlling and reducing uncertainties, here we demonstrate the significance of integrating modeling and observations as they are complementary and propose to treat complex land-surface systems with a stochastic perspective. In addition, through the description of two modern methods of data assimilation, we delineate how data assimilation characterizes and controls uncertainties by maximally integrating modeling and observational information, thereby enhancing the predictability and observability of the system. We suggest that the next-generation modeling should depict the statistical distribution of dynamic systems and that the observations should capture spatial heterogeneity and quantify the representativeness error of observations.

27.U60656
Li Z. et al. The measurement and model construction of complex permittivity of vegetation // Science China Earth Sciences. 2014. Vol. 57, № 4. P. 729–740.

The complex permittivity of targeted objects is an important factor that influences its microwave radiation and scattering characteristics. In the quantitative research of microwave remote sensing, the study of the dielectric properties of the vegetation to establish the relationship between its specific physical parameters and complex permittivity is fundamental. In this study, six categories of vegetation samples were collected at the city of Zhangye, a key research area of the Heihe watershed allied telemetry experimental research. The vector network analyzer E8362B was used to measure the complex permittivity of these samples from 0.2 to 20 GHz by the coaxial probe technique. The research focused mainly on the corn leaves, and an empirical model was established between the gravimetric moisture and the real/imaginary parts of complex permittivity at the main frequency points of microwave sensors. Furthermore, the empirical model and the classical Debye-Cole model were compared and verified by the measured data collected from the Huailai County of Hebei Province. The results show that the newly-established empirical model is more accurate and more practical as compared to the traditional Debye-Cole model.

28.
Liao A.P. et al. High-resolution remote sensing mapping of global land water // Science China Earth Sciences. 2014. Vol. 57, № 10. P. 2305–2316.

Land water, one of the important components of land cover, is the indispensable and important basic information for climate change studies, ecological environment assessment, macro-control analysis, etc. This article describes the overall study on land water in the program of global land cover remote sensing mapping. Through collection and processing of Landsat TM/ETM+, China’s HJ-1 satellite image, etc., the program achieves an effective overlay of global multi-spectral image of 30 m resolution for two base years, namely, 2000 and 2010, with the image rectification accuracy meeting the requirements of 1:200000 mapping and the error in registration of images for the two periods being controlled within 1 pixel. The indexes were designed and selected reasonably based on spectral features and geometric shapes of water on the scale of 30 m resolution, the water information was extracted in an elaborate way by combining a simple and easy operation through pixel-based classification method with a comprehensive utilization of various rules and knowledge through the object-oriented classification method, and finally the classification results were further optimized and improved by the human-computer interaction, thus realizing high-resolution remote sensing mapping of global water. The completed global land water data results, including Global Land 30-water 2000 and Global Land 30-water 2010, are the classification results featuring the highest resolution on a global scale, and the overall accuracy of self-assessment is 96%. These data are the important basic data for developing relevant studies, such as analyzing spatial distribution pattern of global land water, revealing regional difference, studying space-time fluctuation law, and diagnosing health of ecological environment.

29.
Lin F.-C. et al. Storage and processing of massive remote sensing images using a novel cloud computing platform // Giscience & Remote Sensing. 2013. Vol. 50, № 3. P. 322–336.

In recent years, the rapid development of remote sensing technology has proliferated high-quality images that occupy larger and larger storage spaces. Video has become widespread for environmental observation. Hence, digital data is growing exponentially, and geographic information systems must determine how to manage and process images and video effectively. Researchers cannot limit themselves to desktop PCs due to computational and storage limits. The aim of this article was to propose and implement an architectural design for a novel cloud computing platform based on two Web Coverage Service and Web Map Service interfaces from the Open Geospatial Consortium (OGC), cloud storage from Hadoop Distributed File System (HDFS), and image processing from MapReduce. Results are presented on tablet computers (Asus transformer pad) and websites. Within this framework, we implemented image management as well as simple WebGIS and created an experiment in read/write performance with four kinds of data sets (normal distribution, skew to left, skew to right, and peak in left and right). For write/read performance with HDFS, the proposed system outperformed a local file system for large files (most files ranged from 8 MB to 10 MB), with many concurrent users (simulated threads equal to 40 or 50). An observer on the ground with a touchscreen can identify central points (man-made centroids) of real-time images by tapping the tablet with a finger. A second experiment revealed that the convergence for human intervention was better than convergence for random centroids in two kinds of cloud computing environments.

30.
Liu C. et al. Estimation of sea ice thickness in the Bohai Sea using a combination of VIS/NIR and SAR images // Giscience & Remote Sensing. 2015. Vol. 52, № 2. P. 115–130.

The thicknesses of level and rough sea ice in the Bohai Sea were estimated, using Huan Jing-1 (HJ-1) charge-coupled device (CCD) images and environmental satellite (ENVISAT) advanced synthetic aperture radar (ASAR) images, respectively. Two empirical models were developed, one to describe the relationship between the reflectance of visible/near-infrared (VIS/NIR) imagery and level ice thickness and one to describe the relationship between the backscattering coefficient of synthetic aperture radar (SAR) imagery and rough ice thickness. The results showed that the VIS/NIR images were more suitable for distinguishing sea ice from sea water, and the active microwave remote sensing images were suitable for determining the difference between level and rough sea ice. The thickness of the level sea ice was logarithmically related to the VIS/NIR reflectance, and the R-2 value of the fitted curve was 0.99 with a root mean square error (RMSE) of 1.0cm. In contrast, the thickness of the rough sea ice was exponentially related to the SAR backscattering coefficient, and the R-2 value of the fitted curve was 0.90 with an RMSE of 2.3cm. The thicknesses of level and rough sea ice were then calculated using the empirical models, and the results reflected the thickness distribution of sea ice in the Bohai Sea. We concluded that high-resolution images can accurately extract the sea ice area and estimate the thickness of sea ice.

31.U60656
Liu X.T. et al. Daytime precipitation identification scheme based on multiple cloud parameters retrieved from visible and infrared measurements // Science China Earth Sciences. 2014. Vol. 57, № 9. P. 2112–2124.

Visible and infrared (VIR) measurements and the retrieved cloud parameters are commonly used in precipitation identification algorithms, since the VIR observations from satellites, especially geostationary satellites, have high spatial and temporal resolutions. Combined measurements from visible/infrared scanner (VIRS) and precipitation radar (PR) aboard the Tropical Rainfall Measuring Mission (TRMM) satellite are analyzed, and three cloud parameters, i.e., cloud optical thickness (COT), effective radius (Re), and brightness temperature of VIRS channel 4 (BT4), are particularly considered to characterize the cloud status. By associating the information from VIRS-derived cloud parameters with those from precipitation detected by PR, we propose a new method for discriminating precipitation in daytime called Precipitation Identification Scheme from Cloud Parameters information (PISCP). It is essentially a lookup table (LUT) approach that is deduced from the optimal equitable threat score (ETS) statistics within 3-dimensional space of the chosen cloud parameters. South and East China is selected as a typical area representing land surface, and the East China Sea and Yellow Sea is selected as typical oceanic area to assess the performance of the new scheme. It is proved that PISCP performs well in discriminating precipitation over both land and oceanic areas. Especially, over ocean, precipitating clouds (PCs) and non-precipitating clouds (N-PCs) are well distinguished by PISCP, with the probability of detection (POD) near 0.80, the probability of false detection (POFD) about 0.07, and the ETS higher than 0.43. The overall spatial distribution of PCs fraction estimated by PISCP is consistent with that by PR, implying that the precipitation data produced by PISCP have great potentials in relevant applications where radar data are unavailable.

32.U60656
Luo D.L. et al. Distribution and changes of active layer thickness (ALT) and soil temperature (TTOP) in the source area of the Yellow River using the GIPL model // Science China Earth Sciences. 2014. Vol. 57, № 8. P. 1834–1845.

Active layer thickness (ALT) is critical to the understanding of the surface energy balance, hydrological cycles, plant growth, and cold region engineering projects in permafrost regions. The temperature at the bottom of the active layer, a boundary layer between the equilibrium thermal state (in permafrost below) and transient thermal state (in the atmosphere and surface canopies above), is an important parameter to reflect the existence and thermal stability of permafrost. In this study, the Geophysical Institute Permafrost Model (GIPL) was used to model the spatial distribution of and changes in ALT and soil temperature in the Source Area of the Yellow River (SAYR), where continuous, discontinuous, and sporadic permafrost coexists with seasonally frozen ground. Monthly air temperatures downscaled from the CRU TS3.0 datasets, monthly snow depth derived from the passive microwave remote-sensing data SMMR and SSM/I, and vegetation patterns and soil properties at scale of 1:1000000 were used as input data after modified with GIS techniques. The model validation was carried out carefully with ALT in the SAYR has significantly increased from 1.8 m in 1980 to 2.4 m in 2006 at an average rate of 2.2 cm yr-1. The mean annual temperature at the bottom of the active layer, or temperature at the top of permafrost (TTOP) rose substantially from -1.1°C in 1980 to -0.6°C in 2006 at an average rate of 0.018°C yr-1. The increasing rate of the ALT and TTOP has accelerated since 2000. Regional warming and degradation of permafrost has also occurred, and the changes in the areal extent of regions with a sub-zero TTOP shrank from 2.4?104 to 2.2?104 km2 at an average rate of 74 km2 yr-1. Changes of ALT and temperature have adversely affected the environmental stability in the SAYR.

33.U37081
Merchant C.J. et al. Sea surface temperature from a geostationary satellite by optimal estimation // Remote Sensing of Environment. 2009. Vol. 113, № 2. P. 445–457.

Optimal estimation (OE) is applied as a technique for retrieving sea surface temperature (SST) from thermal imagery obtained by the Spinning Enhanced Visible and Infra-Red Imager (SEVIRI) on Meteosat 9. OE requires simulation of observations as part of the retrieval process, and this is done here using numerical weather prediction fields and a fast radiative transfer model. Bias correction of the simulated brightness temperatures (BTs) is found to be a necessary step before retrieval, and is achieved by filtered averaging of simulations minus observations over a time period of 20 days and spatial scale of 2.5° in latitude and longitude. Throughout this study, BT observations are clear-sky averages over cells of size 0.5° in latitude and longitude. Results for the OE SST are compared to results using a traditional non-linear retrieval algorithm (“NLSST”), both validated against a set of 30108 night-time matches with drifting buoy observations. For the OE SST the mean difference with respect to drifter SSTs is ? 0.01 K and the standard deviation is 0.47 K, compared to ? 0.38 K and 0.70 K respectively for the NLSST algorithm. Perhaps more importantly, systematic biases in NLSST with respect to geographical location, atmospheric water vapour and satellite zenith angle are greatly reduced for the OE SST. However, the OE SST is calculated to have a lower sensitivity of retrieved SST to true SST variations than the NLSST. This feature would be a disadvantage for observing SST fronts and diurnal variability, and raises questions as to how best to exploit OE techniques at SEVIRI's full spatial resolution.

34.U37081
Naesset E. Effects of different sensors, flying altitudes, and pulse repetition frequencies on forest canopy metrics and biophysical stand properties derived from small-footprint airborne laser data // Remote Sensing of Environment. 2009. Vol. 113, № 1. P. 148–159.

Canopy height distributions were created from small-footprint airborne laser scanner (ALS) data collected over 40 field sample plots with size 1000 m2 located in mature conifer forest. ALS data were collected with two different instruments, i.e., the ALTM 1233 and ALTM 3100 laser scanners (Optech Inc.). The ALTM 1233 data were acquired at a flying altitude of 1200 m and a pulse repetition frequency (PRF) of 33 kHz. Three different acquisitions were carried out with ALTM 3100, i.e., (1) a flying altitude of 1100 m and a PRF of 50 kHz, (2) a flying altitude of 1100 m and a PRF of 100 kHz, and (3) a flying altitude of 2000 m and a PRF of 50 kHz. Height percentiles, mean and maximum height values, coefficients of variation of the heights, and canopy density at different height intervals above the ground were derived from the four different ALS datasets and for single + first and last echoes of the ALS data separately. The ALS-derived height- and density variables were assessed in pair-wise comparisons to evaluate the effects of (a) instrument, (b) flying altitude, and (c) PRF. A systematic shift in height values of up to 0.3 m between sensors when the first echoes were compared was demonstrated. Also the density-related variables differed significantly between the two instruments. Comparisons of flying altitudes and PRFs revealed upwards shifted canopy height distributions for the highest flying altitude (2000 m) and the lowest PRF (50 kHz). The distribution of echoes on different echo categories, i.e., single and multiple (first and last) echoes, differed significantly between acquisitions. The proportion of multiple echoes decreased with increasing flying altitude and PRF. Different echo categories have different properties since it is likely that single echoes tend to occur in the densest parts of the tree crowns, i.e., near the apex where the concentration of biological matter is highest and distance to the ground is largest. To assess the influence of instrument, flying altitude, and PRF on biophysical properties derived from ALS data, regression analysis was carried out to relate ALS-derived metrics to mean tree height (hL) and timber volume (V). Cross validation revealed only minor differences in precision for the different ALS acquisitions, but systematic differences between acquisitions of up to 2.5% for hL and 10.7% for V were found when comparing data from different acquisitions.

35.
Nobakht M. et al. The Inylchek Glacier in Kyrgyzstan, Central Asia: Insight on Surface Kinematics from Optical Remote Sensing Imagery // Remote Sensing. 2014. Vol. 6, № 1. P. 841–856.

Mountain chains of Central Asia host a large number of glaciated areas that provide critical water supplies to the semi-arid populated foothills and lowlands of this region. Spatio-temporal variations of glacier flows are a key indicator of the impact of climate change on water resources as the glaciers react sensitively to climate. Satellite remote sensing using optical imagery is an efficient method for studying ice-velocity fields on mountain glaciers. In this study, temporal and spatial changes in surface velocity associated with the Inylchek glacier in Kyrgyzstan are investigated. We present a detailed map for the kinematics of the Inylchek glacier obtained by cross-correlation analysis of Landsat images, acquired between 2000 and 2011, and a set of ASTER images covering the time period between 2001 and 2007. Our results indicate a high-velocity region in the elevated part of the glacier, moving up to a rate of about 0.5 m/day. Time series analysis of optical data reveals some annual variations in the mean surface velocity of the Inylchek during 2000-2011. In particular, our findings suggest an opposite trend between periods of the northward glacial flow in Proletarskyi and Zvezdochka glacier, and the rate of westward motion observed for the main stream of the Inylchek.

36.
Ramachandra T.V., Bharath A.H., Sowmyashree M.V. Monitoring urbanization and its implications in a mega city from space: Spatiotemporal patterns and its indicators // Journal of Environmental Management. 2015. Vol. 148. P. 67–81.

Rapid and invasive urbanization has been associated with depletion of natural resources (vegetation and water resources), which in turn deteriorates the landscape structure and conditions in the local environment. Rapid increase in population due to the migration from rural areas is one of the critical issues of the urban growth. Urbanisation in India is drastically changing the land cover and often resulting in the sprawl. The sprawl regions often lack basic amenities such as treated water supply, sanitation, etc. This necessitates regular monitoring and understanding of the rate of urban development in order to ensure the sustenance of natural resources .Urban sprawl is the extent of urbanization which leads to the development of urban forms with the destruction of ecology and natural landforms. The rate of change of land use and extent of urban sprawl can be efficiently visualized and modelled with the help of geoinformatics. The knowledge of urban area, especially the growth magnitude, shape geometry, and spatial pattern is essential to understand the growth and characteristics of urbanization process. Urban pattern, shape and growth can be quantified using spatial metrics. This communication quantifies the urbanisation and associated growth pattern in Delhi. Spatial data of four decades were analysed to understand land over and land use dynamics. Further the region was divided into 4 zones and into circles of 1 km incrementing radius to understand and quantify the local spatial changes. Results of the landscape metrics indicate that the urban center was highly aggregated and the outskirts and the buffer regions were in the verge of aggregating urban patches. Shannon's Entropy index clearly depicted the outgrowth of sprawl areas in different zones of Delhi.

37.
Ruiz L. et al. Dynamic connectivity of temporary wetlands in the southern Great Plains // Landscape Ecology. 2014. Vol. 29, № 3. P. 507–516.

We quantified fluctuations in the status of individual patches (wetlands) in supporting connectivity within a network of playas, temporary wetlands of the southern Great Plains of North America that are loci for regional biodiversity. We used remote sensing imagery to delineate the location of surface waters in >8,000 playa basins in a similar to 31,900 km(2) portion of Texas and quantified connectivity in this region from 2007 to 2011. We ranked playas as stepping-stones, cutpoints, and hubs at different levels of environmental conditions (regionally wet, dry, and average periods of precipitation) for dispersal distances ranging from 0.5 to 34 km, representing a range of species' vagilities, to provide baseline dynamics within an area likely to experience disrupted connectivity due to anthropogenic activities. An individual playa's status as a stepping-stone, cutpoint, or hub was highly variable over time (only a single playa was a top 20 stepping-stone, cutpoint, or hub in >50 % of all of the dates examined). Coalescence of the inundated playa network usually occurred at >= 10 km dispersal distance and depended on wetland density, indicating that critical thresholds in connectivity arose from synergistic effects of dispersal ability (spatial scale) and wet playa occurrence (a function of precipitation). Organisms with dispersal capabilities limited to <10 km routinely experienced effective isolation during our study. Connectivity is thus a dynamic emergent landscape property, so management to maintain connectivity for wildlife within ephemeral habitats like inundated playas will need to move beyond a patch-based focus to a network focus by including connectivity as a dynamic landscape property.

38.
Sackov I., Kardos M. Forest delineation based on LiDAR data and vertical accuracy of the terrain model in forest and non-forest area // Annals of Forest Research. 2014. Vol. 57, № 1. P. 119–136.

This paper deals with the use of airborne laser scanning data (ALS) in the process of the automatic delineation of forest and the generation of digital terrain models (DTM) in forested and non-forested areas. The study area where the procedures presented were examined is part of the University Forest Enterprise, Technical University in Zvolen (48 degrees 37' N, 19 degrees 04' E). A partial modification of existing solutions that iteratively takes into account the criteria of minimum area, height, width and crown coverage is presented within the forest delineation. At the same time this approach also evaluates the mutual distance of identified crowns and the presence of buildings. Compared with manually identified forest boundaries, the accuracy of the automated procedure in the study area reached the value of 93%. In the DTM generation, various alternative methods of interpolation and conversion were used, while ALS data from the summer and winter seasons were also available. The results showed that laser scanning in the area of interest provided systematically overestimated data for the DTM generation. The largest deviations of the DTM were found in terrains based on ALS data from the summer season, with a significant slope, regardless of the complexity of the afforestation structure (except for the youngest forest). In older stands and unforested areas, both with a moderate slope, the DTM accuracy achieved was in the range +/- 6-17 cm.

39.U37081
Schneider J., Grosse G., Wagner D. Land cover classification of tundra environments in the Arctic Lena Delta based on Landsat 7 ETM+ data and its application for upscaling of methane emissions // Remote Sensing of Environment. 2009. Vol. 113, № 2. P. 380–391.

The Lena River Delta, situated in Northern Siberia (72.0–73.8° N, 122.0–129.5° E), is the largest Arctic delta and covers 29,000 km2. Since natural deltas are characterised by complex geomorphological patterns and various types of ecosystems, high spatial resolution information on the distribution and extent of the delta environments is necessary for a spatial assessment and accurate quantification of biogeochemical processes as drivers for the emission of greenhouse gases from tundra soils. In this study, the first land cover classification for the entire Lena Delta based on Landsat 7 Enhanced Thematic Mapper (ETM+) images was conducted and used for the quantification of methane emissions from the delta ecosystems on the regional scale. Nine land cover classes of aquatic and terrestrial ecosystems in the wetland dominated (72%) Lena Delta could be defined by this classification approach. The mean daily methane emission of the entire Lena Delta was calculated with 10.35 mg CH4 m? 2 d? 1. Taking our multi-scale approach into account we find that the methane source strength of certain tundra wetland types is lower than calculated previously on coarser scales.

40.U59358
Sinha A.K. et al. Geoinformatics: Transforming data to knowledge for geosciences // GSA Today. 2010. Vol. 20, № 12. P. 4–10.

An integrative view of Earth as a system, based on multidisciplinary data, has become one of the most compelling reasons for research and education in the geosciences. It is now necessary to establish a modern infrastructure that can support the transformation of data to knowledge. Such an information infrastructure for geosciences is contained within the emerging science of geoinformatics, which seeks to promote the utilizetion and integration of complex, multidisciplinary data in seeking solutions to geoscience-based societal challenges.

41.U37081
Sirguey P., Mathieu R., Arnaud Y. Subpixel monitoring of the seasonal snow cover with MODIS at 250 m spatial resolution in the Southern Alps of New Zealand: Methodology and accuracy assessment // Remote Sensing of Environment. 2009. Vol. 113, № 1. P. 160–181.

This study describes a comprehensive method to produce routinely regional maps of seasonal snow cover in the Southern Alps of New Zealand (upper Waitaki basin) on a subpixel basis, and with the MODerate Resolution Imaging Spectroradiometer (MODIS). The method uses an image fusion algorithm to produce snow maps at an improved 250 m spatial resolution in addition to the 500 m resolution snow maps. An iterative approach is used to correct imagery for both atmospheric and topographic effects using daily observations of atmospheric parameters. The computation of ground spectral reflectance enabled the use of image-independent end-members in a constrained linear unmixing technique to achieve a robust estimation of subpixel snow fractions. The accuracy of the snow maps and performance of the algorithm were assessed carefully using eight pairs of synchronic MODIS/ASTER images. ‘Pixel-based’ metrics showed that subpixel snow fractions were retrieved with a Mean Absolute Error of 6.8% at 250 m spatial resolution and 5.1% after aggregation at 500 m spatial resolution. In addition, a ‘feature-based’ metric showed that 90% of the snowlines were depicted generally within 300 m and 200 m of their correct position for the 500-m and 250-m spatial resolution snow maps, respectively. A dataset of 679 maps of subpixel snow fraction was produced for the period from February 2000 to May 2007. These repeated observations of the seasonal snow cover will benefit the ongoing effort to model snowmelt runoff in the region and to improve the estimation and management of water resources.

42.
Smith A.M.S. et al. Remote sensing the vulnerability of vegetation in natural terrestrial ecosystems // Remote Sensing of Environment. 2014. Vol. 154. P. 322–337.

Climate change is altering the species composition, structure, and function of vegetation in natural terrestrial ecosystems. These changes can also impact the essential ecosystem goods and services derived from these ecosystems. Following disturbances, remote-sensing datasets have been used to monitor the disturbance and describe antecedent conditions as a means of understanding vulnerability to change. To a lesser extent, they have also been used to predict when desired ecosystems are vulnerable to degradation or loss. In this paper, we review studies that have applied remote sensing imagery to characterize vegetation vulnerability in both retrospective and prospective modes. We first review vulnerability research in natural terrestrial ecosystems including temperate forests, tropical forests, boreal forests, semi-arid lands, coastal areas, and the arctic. We then evaluate whether remote sensing can evaluate vulnerability sufficiently in advance of future events in order to allow the implementation of mitigation strategies, or whether it can only describe antecedent conditions a posteriori. The majority of existing research has evaluated vulnerability retrospectively, but key studies highlight the considerable potential for the development of early warnings of future vulnerability. We conclude that future research needs to focus on the development of a greater number of remotely sensed metrics to be used in a prospective mode in assessing vulnerability of terrestrial vegetation under change.

43.
Song C., Huang B., Ke L. Modeling and analysis of lake water storage changes on the Tibetan Plateau using multi-mission satellite data // Remote Sensing of Environment. 2013. Vol. 135. P. 25–35.

Estimation of the water storage changes in the lakes of the Tibetan Plateau (TP) is essential for an accurate evaluation of climate change in this alpine region and its impact on the surrounding hydrologic environment. Because of the remoteness and poor accessibility of these alpine lakes, and a lack of lake bathymetric data, estimating their mass budget over the TP poses a considerable challenge. However, the integration of optical remote sensing images, satellite altimetry data, and gravimetry data makes it possible to monitor the overall variations in lake water storage in this extensive region. The ICESat/GLAS altimetry data used in this study reveal that most of the lakes in the TP showed a significant upward tendency (0.2–0.6 m/year) in water level between 2003 and 2009, particularly those lakes that are supplied with a large proportion of glacial meltwater. A series of lake area data derived from Landsat MSS/TM/ETM + imagery over the past four decades indicate that during the 1970–1990 period most of the lakes experienced severe shrinkage, with only some of those in central and western Tibet undergoing expansion. During the 1990–2011 period, in contrast, the majority of the lakes on the TP displayed a remarkably expansion tendency. The total lake area increased from 35,638.11 km2 in the early 1970s to 41,938.66 km2 in 2011.

44.
Vahtmaee E., Kutser T. Classifying the Baltic Sea Shallow Water Habitats Using Image-Based and Spectral Library Methods // Remote Sensing. 2013. Vol. 5, № 5. P. 2451–2474.

The structure of benthic macrophyte habitats is known to indicate the quality of coastal water. Thus, a large-scale analysis of the spatial patterns of coastal marine habitats enables us to adequately estimate the status of valuable coastal marine habitats, provide better evidence for environmental changes and describe processes that are behind the changes. Knowing the spatial distribution of benthic habitats is also important from the coastal management point of view. A big challenge in remote sensing mapping of benthic habitats is to define appropriate mapping classes that are also meaningful from the ecological point of view. In this study, the benthic habitat classification scheme was defined for the study areas in the relatively turbid north-eastern Baltic Sea coastal environment. Two different classification methods-image-based and the spectral library-method were used for image classification. The image-based classification method can provide benthic habitat maps from coastal areas, but requires extensive field studies. An alternative approach in image classification is to use measured and/or modelled spectral libraries. This method does not require fieldwork at the time of image collection if preliminary information about the potential benthic habitats and their spectral properties, as well as variability in optical water properties exists from earlier studies. A spectral library was generated through radiative transfer model HydroLight computations using measured reflectance spectra from representative benthic substrates and water quality measurements. Our previous results have shown that benthic habitat mapping should be done at high spatial resolution, owing to the small-scale heterogeneity of such habitats in the Estonian coastal waters. In this study, the capability of high spatial resolution hyperspectral airborne a Compact Airborne Spectrographic Imager (CASI) sensor and a high spatial resolution multispectral WorldView-2 satellite sensor were tested for mapping benthic habitats. Initial evaluations of habitat maps indicate that image-based classification provides higher quality benthic maps compared to the spectral library method.

45.
Verrelst J. et al. Optical remote sensing and the retrieval of terrestrial vegetation bio-geophysical properties - A review // Isprs Journal of Photogrammetry and Remote Sensing. 2015. Vol. 108. P. 273–290.

Forthcoming superspectral satellite missions dedicated to land monitoring, as well as planned imaging spectrometers, will unleash an unprecedented data stream. The processing requirements for such large data streams involve processing techniques enabling the spatio-temporally explicit quantification of vegetation properties. Typically retrieval must be accurate, robust and fast. Hence, there is a strict requirement to identify next-generation bio-geophysical variable retrieval algorithms which can be molded into an operational processing chain. This paper offers a review of state-of-the-art retrieval methods for quantitative terrestrial bio-geophysical variable extraction using optical remote sensing imagery. We can categorize these methods into (1) parametric regression, (2) non-parametric regression, (3) physically-based and (4) hybrid methods. Hybrid methods combine generic capabilities of physically-based methods with flexible and computationally efficient methods, typically non-parametric regression methods. A review of the theoretical basis of all these methods is given first and followed by published applications. This paper focusses on: (1) retrievability of bio-geophysical variables, (2) ability to generate multiple outputs, (3) possibilities for model transparency description, (4) mapping speed, and (5) possibilities for uncertainty retrieval. Finally, the prospects of implementing these methods into future processing chains for operational retrieval of vegetation properties are presented and discussed.

46.
Wen X.H. et al. Numerical simulation and data assimilation of the water-energy cycle over semiarid northeastern China // Science China Earth Sciences. 2014. Vol. 57, № 10. P. 2340–2356.

The default fractional vegetation cover and terrain height were replaced by the estimated fractional vegetation cover, which was calculated by the Normalized Difference Vegetation Index (NDVI) of Earth Observing System Moderate-Resolution Imaging Spectroradiometer (EOS-MODIS) and the Digital Elevation Model of the Shuttle Radar Topography Mission (SRTM) system. The near-surface meteorological elements over northeastern China were assimilated into the three-dimensional variational data assimilation system (3DVar) module in the Weather Research and Forecasting (WRF) model. The structure and daily variations of air temperature, humidity, wind and energy fields over northeastern China were simulated using the WRF model. Four groups of numerical experiments were performed, and the simulation results were analyzed of latent heat flux, sensible heat flux, and their relationships with changes in the surface energy flux due to soil moisture and precipitation over different surfaces. The simulations were compared with observations of the stations Tongyu, Naiman, Jinzhou, and Miyun from June to August, 2009. The results showed that the WRF model achieves high-quality simulations of the diurnal characteristics of the surface layer temperature, wind direction, net radiation, sensible heat flux, and latent heat flux over semiarid northeastern China in the summer. The simulated near-surface temperature, relative humidity, and wind speed were improved in the data assimilation case (Case 2) compared with control case (Case 1). The simulated sensible heat fluxes and surface heat fluxes were improved by the land surface parameterization case (Case 3) and the combined case (Case 4). The simulated temporal variations in soil moisture over the northeastern arid areas agree well with observations in Case 4, but the simulated precipitation should be improved in the WRF model. This study could improve the land surface parameters by utilizing remote sensing data and could further improve atmospheric elements with a data assimilation system. This work provides an effective attempt at combining multi-source data with different spatial and temporal scales into numerical simulations. The assimilation datasets generated by this work can be applied to research on climate change and environmental monitoring of arid lands, as well as research on the formation and stability of climate over semiarid areas.

47.U21083
Wilken T. et al. A spectrograph for exoplanet observations calibrated at the centimetre-per-second level // Nature. 2012. Vol. 485, № 7400. P. 611–614.

The best spectrographs are limited in stability by their calibration light source(1). Laser frequency combs are the ideal calibrators for astronomical spectrographs(2). They emit a spectrum of lines that are equally spaced in frequency(3) and that are as accurate and stable as the atomic clock relative to which the comb is stabilized. Absolute calibration(4) provides the radial velocity of an astronomical object relative to the observer (on Earth). For the detection of Earth-mass exoplanets(5,6) in Earth-like orbits around solar-type stars, or of cosmic acceleration(7-9), the observable is a tiny velocity change of less than 10 cm s(-1), where the repeatability of the calibration-the variation in stability across observations-is important. Hitherto, only laboratory systems(10-12) or spectrograph calibrations of limited performance(4,13,14) have been demonstrated. Here we report the calibration of an astronomical spectrograph with a short-term Doppler shift repeatability of 2.5 cm s(-1), and use it to monitor the star HD75289 and recompute the orbit of its planet. This repeatability should make it possible to detect Earth-like planets in the habitable zone of star or even to measure the cosmic acceleration directly.

48.
Xu C. et al. Landslide hazard mapping using GIS and weight of evidence model in Qingshui River watershed of 2008 Wenchuan earthquake struck region // Journal of Earth Science. 2012. Vol. 23, № 1. P. 97–120.

Tens of thousands of landslides were triggered by May 12, 2008 earthquake over a broad area. The main purpose of this article is to apply and verify earthquake-triggered landslide hazard analysis techniques by using weight of evidence modeling in Qingshui (ae...ae degrees ') River watershed, Deyang (a3/4 center dot e similar to(3)) City, Sichuan (a >> a center dot e) Province, China. Two thousand three hundred and twenty-one landslides were interpreted in the study area from aerial photographs and multi-source remote sensing imageries post-earthquake, verified by field surveys. The landslide inventory in the study area was established. A spatial database, including landslides and associated controlling parameters that may have influence on the occurrence of landslides, was constructed from topographic maps, geological maps, and enhanced thematic mapper (ETM+) remote sensing imageries. The factors that influence landslide occurrence, such as slope angle, aspect, curvature, elevation, flow accumulation, distance from drainages, and distance from roads were calculated from the topographic maps. Lithology, distance from seismogenic fault, distance from all faults, and distance from stratigraphic boundaries were derived from the geological maps. Normalized difference vegetation index (NDVI) was extracted from ETM+ images. Seismic intensity zoning was collected from Wenchuan (ae +/- a center dot e) Ms8.0 Earthquake Intensity Distribution Map published by the China Earthquake Administration. Landslide hazard indices were calculated using the weight of evidence model, and landslide hazard maps were calculated from using different controlling parameters cases. The hazard map was compared with known landslide locations and verified. The success accuracy percentage of using all 13 controlling parameters was 71.82%. The resulting landslide hazard map showed five classes of landslide hazard, i.e., very high, high, moderate, low, and very low. The validation results showed satisfactory agreement between the hazard map and the existing landslides distribution data. The landslide hazard map can be used to identify and delineate unstable hazard-prone areas. It can also help planners to choose favorable locations for development schemes, such as infrastructural, buildings, road constructions, and environmental protection.

49.
Yue P. et al. Intelligent services for discovery of complex geospatial features from remote sensing imagery // Isprs Journal of Photogrammetry and Remote Sensing. 2013. Vol. 83. P. 151–164.

Remote sensing imagery has been commonly used by intelligence analysts to discover geospatial features, including complex ones. The overwhelming volume of routine image acquisition requires automated methods or systems for feature discovery instead of manual image interpretation. The methods of extraction of elementary ground features such as buildings and roads from remote sensing imagery have been studied extensively. The discovery of complex geospatial features, however, is still rather understudied. A complex feature, such as a Weapon of Mass Destruction (WMD) proliferation facility, is spatially composed of elementary features (e.g., buildings for hosting fuel concentration machines, cooling towers, transportation roads, and fences). Such spatial semantics, together with thematic semantics of feature types, can be used to discover complex geospatial features. This paper proposes a workflow-based approach for discovery of complex geospatial features that uses geospatial semantics and services. The elementary features extracted from imagery are archived in distributed Web Feature Services (WFSs) and discoverable from a catalogue service. Using spatial semantics among elementary features and thematic semantics among feature types, workflow-based service chains can be constructed to locate semantically-related complex features in imagery. The workflows are reusable and can provide on-demand discovery of complex features in a distributed environment. (C) 2013 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS)

50.
Zhang H.S. et al. Phytoplankton and chlorophyll a relationships with ENSO in Prydz Bay, East Antarctica // Science China Earth Sciences. 2014. Vol. 57, № 12. P. 3073–3083.

The historical data of phytoplankton and chlorophyll a (Chl a) (1990–2002) obtained during the Chinese National Antarctic Research Expedition (CHINARE) in the Prydz Bay have been integrated. The results showed that the temperature, salinity, nutrients, and oxygen of seawater changed when El Nino/La Nina occurred. The variation of biological communities reflected the response of ecosystem to environmental changes. During El Nino period, Chl a concentration and phytoplankton community structure changed significantly, and the relative proportion of diatoms increased while dinoflagellates decreased. During La Nina period, the proportion of diatoms decreased, but the golden-brown algae and blue-green algae increased significantly. The variation of phytoplankton population directly affected the biodiversity of the bay, which were also quite sensitive to the marine environment changes. Meanwhile, the satellite remote sensing data of 2002–2011 (December–March) have been used to study the temporal connection change of Chl a and phytoplankton in the Prydz Bay. We found that there were significant differences in the monthly variation characteristics of satellite remote sensing Chl a and sea surface temperature (SST), which had some links with sea ice melting and El Nino/La Nina events. We found that the start time of bloom advanced, lagged or synchronized with the changes of the SST, and we also found the occurrence time of phytoplankton bloom corresponded with the sea ice melting inner bay. To some extent, this study will help us understand the relationships between ENSO events and the phytoplankton bloom in the Southern Ocean.

51.U60656
Zhong B. et al. Land cover mapping using time series HJ-1/CCD data // Science China Earth Sciences. 2014. Vol. 57, № 8. P. 1790–1799.

It is very difficult to have remote sensing data with both high spatial resolution and high temporal frequency; thus, two categories of land-use mapping methodology have been developed separately for coarser resolution and finer resolution data. The first category uses time series of data to retrieve the variation of land surface for classification, which are usually used for coarser resolution data with high temporal frequency. The second category uses fine spatial resolution data to classify different land surface. With the launch of Chinese satellite constellation HJ-1in 2008, four 30 m spatial resolution CCDs with about 360 km coverage for each one onboard two satellites made a revisit period of two days, which brought a new type of data with both high spatial resolution and high temporal frequency. Therefore, by taking the spatiotemporal advantage of HJ-1/CCD data we propose a new method for finer resolution land cover mapping using the time series HJ-1/CCD data, which can greatly improve the land cover mapping accuracy. In our two study areas, the very high resolution remote sensing data within Google Earth are used to validate the land cover mapping results, which shows a very high mapping accuracy of 95.76% and 83.78% and a high Kappa coefficient of 0.9423 and 0.8165 in the Dahuofang area of Liaoning Province and the Heiquan area of Gansu Province respectively.

52.
Zhu P., Gong P. Suitability mapping of global wetland areas and validation with remotely sensed data // Science China Earth Sciences. 2014. Vol. 57, № 10. P. 2283–2292.

With increasing urbanization and agricultural expansion, large tracts of wetlands have been either disturbed or converted to other uses. To protect wetlands, accurate distribution maps are needed. However, because of the dramatic diversity of wetlands and difficulties in field work, wetland mapping on a large spatial scale is very difficult to do. Until recently there were only a few high resolution global wetland distribution datasets developed for wetland protection and restoration. In this paper, we used hydrologic and climatic variables in combination with Compound Topographic Index (CTI) data in modeling the average annual water table depth at 30 arc-second grids over the continental areas of the world except for Antarctica. The water table depth data were modeled without considering influences of anthropogenic activities. We adopted a relationship between potential wetland distribution and water table depth to develop the global wetland suitability distribution dataset. The modeling results showed that the total area of global wetland reached 3.316?107 km2. Remote-sensing-based validation based on a compilation of wetland areas from multiple sources indicates that the overall accuracy of our product is 83.7%. This result can be used as the basis for mapping the actual global wetland distribution. Because the modeling process did not account for the impact of anthropogenic water management such as irrigation and reservoir construction over suitable wetland areas, our result represents the upper bound of wetland areas when compared with some other global wetland datasets. Our method requires relatively fewer datasets and has a higher accuracy than a recently developed global wetland dataset.

53.U60656
Zou M.M. et al. Accuracy analysis of PPDF-based method to parameterize aerosol scattering effect // Science China Earth Sciences. 2014. Vol. 57, № 8. P. 1807–1815.

We introduce the path length probability density function (PPDF) method, which is based on an equivalence theorem and parameterizes the aerosol scattering effect by adding four factors to the atmospheric transmittance model. Using simulated observations in the O2-A band, we examined the utility of the PPDF-based method to account for the aerosol scattering effect. First, observations were simulated using a forward model under different aerosol conditions; PPDF factors were then retrieved using an optimal estimation method; PPDF factors were used to reconstruct the observations; and finally, simulated true observations and reconstructions were compared. Analysis of the difference between the true observations and reconstructions confirmed the utility of the PPDF-based method. Additionally, the O2 band was demonstrated to be an efficient observing band for assisting the remote sensing of atmospheric trace gases in the near-infrared band. x

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Алексанин А.И., Ким В. Автоматическое обнаружение внутренних волн на спутниковых изображениях и оценка плотности перемешанного слоя // Исследование Земли из космоса. 2015. № 1. С. 44.

В работе предлагается алгоритм автоматического обнаружения внутренних волн по спутниковым изображениям радиометров MODIS видимого спектрального диапазона. Алгоритм основан на преобразовании Хафа и работает пофрагментно. Рассмотрены источники ошибок распознавания внутренних волн и возможности отбраковки ложных объектов. При обнаружении цуга внутренних волн на одиночном изображении можно получить оценку волнового числа. Длина внутренних волн на изображениях, использовавшихся в экспериментах, лежала в диапазоне от 1300 до 2200 м. Скорость распространения внутренних волн оценивалась по паре смежных витков Aqua и Terra. Эти параметры были использованы для расчета плотностных характеристик перемешанного слоя на основе решений уравнения распространения внутренних волн в двухслойной среде со слоями постоянной плотности. Рассчитанные перепады плотности слоев, полученные по спутниковым данным, показывают хорошее соответствие со значениями in situ измерений.

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Анисимов О.А., Жильцова Е.Л., Разживин В.Ю. Моделирование биопродуктивности в Арктической зоне России с использованием спутниковых наблюдений // Исследование Земли из космоса. 2015. № 3. С. 60-70.

Использованы данные спутниковых наблюдений NOAA за 1982-2012 гг. для анализа современных изменений продуктивности растительности бореальной и тундровой зоны России. Рассчитаны тренды индекса, характеризующего фотосинтетическую активность для растительных зон арктической территории России раздельно для Еропейского, Западно-Сибирского, Восточно-Сибирского и Дальневосточного секторов и проведено их сравнение. Этот индекс представляет собой нормализованную разность интенсивностей отраженного света в красном и инфракрасном диапазоне (Normalized Difference Vegetatiuon Index, NDVI) и широко используется как показатель количества фотосинтетически активной биомассы. Проведен многофакторный статистический анализ связи продуктивности растительности различных зон, оцениваемой по индексу NDVI, с климатическими индексами - предикторами, характеризующими соотношения температурного режима и увлажнения. Совокупность построенных по его результатам регрессионных уравнений, оценивающих продуктивность биомов на зональном градиенте от северной тундры до бореального леса как функцию климатических параметров и индексов, составила эмпирико-статистическую модель, по которой проведены расчеты с использованием климатической проекции. Согласно полученным результатам, наблюдаемое во всех арктических зонах увеличение продуктивности продолжится в последующие десятилетия. К середине XXI в. продуктивность в отдельных зонах арктической растительности может увеличиться до 30% от ее современной величины.

56.009058
Арманд Н.А., Захаров А.И., Захарова Л.Н. Космические радары с синтезированной апертурой в дистанционном зондировании земли - современные системы и перспективные проекты // Исследование Земли из космоса. 2010. № 2. С. 3-13.

Приведен обзор областейприменения радаров с синтезированной апертурой в дистанционном зондировании Земли (ДЗЗ) из космоса. Указаны требования к параметрам зондирующего сигнала в зависимости от решаемой задачи. Рассмотрены современные космические радарные миссии, способы комплексирования и обработки информации, описаны перспективные системы и конфигурации орбитальных радарных группировок.

57.033856
Боярчук К.А., Карелин А.В., Надольский А.В. Дистанционное зондирование предвестников землетрясений из космоса на основе метода «химического потенциала» по данным метеопараметров // Космонавтика и ракетостроение. 2010. № 2 (59). С. 142-150.

Даётся физическое обоснование метода мониторинга предвестников землетрясений на основе обработки результатов метеонаблюдений (влажности и температуры) и предварительных расчётов. Показываются существенная флуктуация поправки химического потенциала паров воды в атмосфере за несколько дней до землетрясения и явная зависимость абсолютной величины упомянутой поправки от расстояния между его эпицентром и точкой наблюдения на Земле. Предлагается использование данного метода при функционировании космической группировки спутников, оснащённых требуемым для мониторинга инструментарием: инфракрасным (ИК) радиометром и модулем температурно-влажностного зондирования атмосферы (МТВЗА) - сверхвысокочастотным (СВЧ) радиометром спутника «Метеор М» № 1.

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Бычков Д.М., Иванов В.К., Цымбал Н., Яцевич С.Е. Определение путей миграции грунтовых вод в зонах подтопления и заболачивания при активно-пассивном авиационном дистанционном зондировании // Физические основы приборостроения. 2014. Т. 3. № 2 (11). С. 58-65.

Анализируются результаты отработки метода выявления проявлений путей миграции грунтовых вод по скрытым руслам древних рек в зонах подтопления и заболачивания, по данным суточной и сезонной радиолокационной, радиотепловой (термальной ИК) и оптической авиационной съемки комплексом АКДЗ-30.

59.009058
Веселов Ю.Г., Островский А.С. Оценка эффективности алгоритмов интерполяции при масштабировании цифровых аэрокосмических изображений // Исследование Земли из космоса. 2011. № 4. С. 19-32.

Получены зависимости оценки разрешающей способности от типа интерполяции при масштабировании аэрокосмических изображений. Проведен подробный анализ эффективности применения различных алгоритмов интерполяции при масштабировании в ходе дешифрирования штриховых тест-объектов на цифровом изображении.

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Глоточкин А.Д. и др. Дистанционное зондирование Земли: целесообразность применения космических методов для определения нефтегазоносности исследуемых регионов // Космонавтика и ракетостроение. 2010. № 2 (59). С. 166-170.

Обосновывается экономическая целесообразность применения космических методов, позволяющих существенно сокращать объём сейсморазведочных работ, их стоимость и сроки проведения, и в конечном счёте увеличивать достоверность прогноза нефтегазоносности выделенных локальных структур исследуемых регионов.

61.01140X
Запевалов А.С., Лебедев Н.Е. Моделирование статистических характеристик поверхности океана при дистанционном зондировании в оптическом диапазоне // Оптика атмосферы и океана. 2014. Т. 27. № 1. С. 28-33.

В настоящее время наиболее широко применяемым распределением уклонов морской поверхности является распределение Грама–Шарлье. Проанализированы ограничения его использования при моделировании отражения света от морской поверхности. Показано, что распределение Грама–Шарлье не позволяет строить оптические изображения во всем диапазоне углов зондирования, в котором работают оптические сканеры, установленные на низкоорбитальных космических аппаратах. Получены эмпирические соотношения, связывающие статистические моменты уклонов морской поверхности и их углов.

62.002453
Книжников Ю.Ф. Перспективный подход к постановке учебных курсов по аэрокосмическому (дистанционному) зондированию // Известия Высших Учебных Заведений. Геодезия и аэрофотосъемка. 2013. № 3. С. 125-130.

Предлагаемый переход к постановке учебных курсов по дистанционному зондированию в природоведческих вузах рассматривает аэрокосмический снимок в качестве модели объекта, явления, процесса или геосистемы в целом. Новую постановку учебных курсов целесообразнее начать с раздела, посвящённого стереоскопической модели, опираясь на опыт МГУ, где разрабатывается соответствующий учебный курс, включающий «Компьютерный стереопрактикум». Теоретическая часть курса содержит раздел о психологической концепции стереомодели, предусматривающей синергизм стереоскопического зрения человека и технических средств, и раздел о различных видах стереомоделей, формируемых по разновременным снимкам.

63.001874
Лагуткин В.Н., Репин В.Г., Старостенко А.М. Комплекс алгоритмов выделения динамических объектов на многоспектральных видеоизображениях, получаемых при дистанционном зондировании Земли. // Успехи современной радиоэлектроники. 2011. № 8. С. 57-66.

На основе теории адаптации информационных систем разработан алгоритм выделения неточечных динамически изменяющихся объектов при обработке многоспектральных видеопоследовательностей, получаемых при дистанционном зондировании Земли.

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Мошкин Б.Е., Мошкин Б.Е., Вагин В.А., Жарков А.В., Максименко С.В. и др. Многоцелевой фурье-спектрометр космического базирования (экспериментальный образец) // Приборы и техника эксперимента. 2012. № 6. С. 78-84.

Описан экспериментальный образец многоцелевого фурье-спектрометра МЦФС, предназначенного для дистанционного зондирования Земли. Интерферометр спектрометра выполнен по схеме “двойного маятника” и имеет уголковые отражатели с апертурой 2.5 дюйма. В качестве приемников излучения используются криогенная КРТ-матрица 4 ? 4 и пироэлектрик. Прибор оснащен системой сканирования поперек трассы полета с компенсацией смазывания изображения, вызванного движением космического аппарата.

65.00228X
Переслегин С.В., Халиков З.А. Двухпозиционная квазизеркальная радиолокация морской поверхности // Известия Российской Академии Наук. Физика атмосферы и океана. 2011. Т. 47. № 4. С. 562-576.

Основные особенности двухпозиционной радиолокации морской поверхности рассматриваются в приближении квазизеркального рассеяния от изотропных поверхностных волн. Диаграммы рассеяния взволнованной поверхности, определяющие энергетику и ширину зоны обзора аэрокосмических локаторов, рассчитываются при горизонтальной поляризации и далеких от надира углах падения облучающего поверхность луча. Рассматриваются факторы, определяющие форму “бликовой дорожки”: проекции разностно-волнового вектора в продольном и поперечном направлениях, интенсивность уклонов развитых ветровых волн и конечный радиус кривизны Земли, что важно в случае зондирования океана из космоса. Разрешающая способность по оси горизонтальной дальности является наихудшей в зеркальной точке, однако на большей части широкой зоны обзора она лишь в несколько раз хуже разрешения обычного (однопозиционного) радара при той же ширине спектра сигнала. Рассматриваются также условия синтезирования диаграммы направленности приемной антенны при наличии двух зон обзора, не разделяющихся по наклонной дальности и влияние нестационарного характера поверхности на фокусировку радара с синтезированной апертурой.

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Рухович Д.И., Королева П.В., Калинина Н.В., Вильчевская Е.В. и др. Государственная почвенная карта - версия ARCINFO // Почвоведение. 2013. № 3. С. 251-267.

Представлены результаты работ первого этапа создания электронной версии государственной почвенной карты (ГПК) как в векторном, так и растровом виде. Впервые проведена полная инвентаризация всех листов ГПК. Векторизация произведена в масштабах и проекциях исходной основы, то есть контуры почв электронного варианта полностью повторяют контуры на бумажных листах ГПК. Изложены методы и задачи цифровой картографии, из которых выделены две, применимые к ГПК - сохранение материалов, накопленных до цифрового века, в новых формах хранения, и предоставление традиционной картографии новых возможностей развития с использованием дистанционного зондирования (ДЗ), цифровых моделей рельефа (ЦМР), совмещения разномасштабных картографических и тематических материалов и т. д. На основе анализа работ по переводу ГПК в цифровой формат сформулированы и систематизированы основные проблемы, встающие перед цифровой версией ГПК в целом; показаны механизмы выполнения ряда задач; перечислены технологии решения части проблем и выделены направления, требующие разработки новых методов. Конечной целью работ по цифровой версии ГПК является создание единой непротиворечивой карты России М 1 : 1 000 000.

67.001874
Старостенко А.М., Лагуткин В.Н. Выбор оптимальных диапазонов для многоспектральных наблюдений объектов при дистанционном зондировании Земли. // Успехи современной радиоэлектроники. 2011. № 8. С. 31-35.

Разработана методика оптимального выбора диапазонов и определения их параметров для наблюдения протяженных объектов с низким уровнем сигнала на многоспектральных изображениях, получаемых при дистанционном зондировании Земли. Критерием оптимизации является максимум вероятности правильного обнаружения при фиксированной вероятности ложной тревоги. Методика учитывает не только соотношения между параметрами сигнала, фона и шума, но и аппаратурные ограничения, возникающие при конструировании аппаратуры наблюдения.

68.001200
Тимофеев В.Ю., Ардюков Д.Г., Соловьев В.М., Шибаев С.В. и др. Межплитные границы Дальневосточного региона России по результатам GPS измерений, сейсморазведочных и сейсмологических данных // Геология и геофизика. 2012. Т. 53. № 4. С. 489-507.

Рассматривается современная геодинамическая обстановка для Дальневосточного региона России, где сходятся три большие тектонические плиты - Евразийская, Северо-Американская и Тихоокеанская, а также несколько микроплит - Охотоморская, Беринговоморская и Амурская. Приведен анализ имеющихся данных о положении межплитных границ и полюсов взаимного вращения плит, о сейсмичности региона. Представлены параметры моделей плитных движений для Северо-Востока России. Анализируется глубинное строение региона с использованием данных, полученных различными геофизическими методами. По профилю г. Магадан-о. Врангеля приводятся результаты, полученные методами ГСЗ, ОГТ и КМПВ.

69.036089
Халафов Р.В.О. Оптимальный синтез высокоинформативных изображений в дистанционном зондировании // Специальная техника. 2013. № 2. С. 40-43.

Предложен метод информационной оптимизации для синтеза высокоинформативных изображений дистанционного зондирования с высоким разрешением. Изложен порядок практической реализации предложенного метода.

70.009058
Эзау И.Н., Чернокульский А.В. Поля конвективной облачности в атлантическом секторе Арктики: спутниковые и наземные наблюдения // Исследование Земли из космоса. 2015. № 2. С. 49.

В работе рассматривается конвективная облачность в Атлантическом секторе Арктики с точки зрения гипотезы пространственно-организованных полей конвекции. Конвективная облачность обычно изучается как локальный процесс - следствие конвективной неустойчивости турбулентного планетарного пограничного слоя над нагреваемой поверхностью. В высоких широтах конвективная облачность имеет иную динамическую природу, а именно связанную с адвекцией холодного воздуха на относительно теплую поверхность. Это приводит к тому, что физические свойства облачности, например тип конвективных облаков, и ее пространственное расположение взаимосвязаны. Показано, что у кромки льда (береговой линии) преобладает кучевая облачность Cu hum, Cu med, организованная в конвективные валы. В то же время над открытым морем преобладает облачность Cu cong, Cb, организованная в конвективные ячейки. Сравнительный анализ изменений конвективной облачности по спутниковым данным ISCCP и наземным наблюдениям выявил несогласованность изменений облачности в регионе: уменьшение доли конвективной облачности по ISCCP и увеличение по данным наземных наблюдений. В целом, согласно выдвигаемой гипотезе, отступление границы льда может приводить к росту конвективной облачности.

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