Proceedings Volume 7478

Remote Sensing for Environmental Monitoring, GIS Applications, and Geology IX

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Proceedings Volume 7478

Remote Sensing for Environmental Monitoring, GIS Applications, and Geology IX

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Volume Details

Date Published: 30 September 2009
Contents: 17 Sessions, 74 Papers, 0 Presentations
Conference: SPIE Remote Sensing 2009
Volume Number: 7478

Table of Contents

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Table of Contents

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  • Front Matter: Volume 7478
  • Radar/SAR Application and Technique
  • Archaeology, Cultural, and Natural Heritage Geospatial Infrastructure I
  • Archaeology, Cultural, and Natural Heritage Geospatial Infrastructure II
  • Data Fusion
  • Geological Remote Sensing
  • Environmental Monitoring I
  • Environmental Monitoring II
  • Environmental Monitoring III
  • Urban Remote Sensing
  • Environmental Monitoring IV
  • Environmental Monitoring V
  • Airborne and High Resolution Remote Sensing I
  • Airborne and High Resolution Remote Sensing II
  • Classification - Evaluation
  • Environmental Monitoring VI
  • Poster Session
Front Matter: Volume 7478
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Front Matter: Volume 7478
This PDF file contains the front matter associated with SPIE Proceedings Volume 7478, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and the Conference Committee listing.
Radar/SAR Application and Technique
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Detection of ground deformation in the broader area of Sharm El-Shiekh (Sinai Peninsula, Egypt) by SAR interferometry
Tarek A. Seleem, Michael Foumelis, Issaak Parcharidis
Sharm El-Shiekh area is located in the most southern part of Sinai Peninsula boarded by the Gulf of Suez to the west and by the Gulf of Aqaba to the east. The present study concerns the application of Multibaseline/Stacking Differential SAR Interferometry (DInSAR) in order to monitor ground deformation rates in the southern part of Sharm El-Shiekh area. The specific technique was applied in order to reduce the influence of atmospheric effects on ground deformation estimates. For this purpose a total number of 24 ENVISAT ASAR scenes covering the period between 2002 and 2008 were processed and analysed. Interferometric results show both patterns of uplift and downlift in the study area. Specifically an area along the coastline with a N-S direction, corresponding to the build up zone of Sharm El-Shiekh, shows average annual subsidence rates between -5 and -7 mm/yr along the line of sight (LOS). On the contrary, Sharm El Maya, an inner zone parallel to the above subsided area, shows slant range uplift of around 5 mm/yr. The obtained results of SAR inteferometry probably indicate the presence of an active fault that affects the coastal zones of Sharm El-Shiekh area.
Segmentation and fusion of building features based on InSAR and optical data
A. Thiele, J. D. Wegner, E. Cadario, et al.
The new generation of space borne SAR sensors provides geometric resolution of one meter, airborne systems even higher. In this high resolution data many features of urban objects become visible, which were beyond the scope of radar remote sensing only a few years ago. Focusing on elevated objects (e.g., urban area), layover, and occlusion issues inevitably arise because of the side-looking SAR sensor principle. In order to support interpretation, SAR data are often analyzed using additional information provided by maps or other remote sensing imagery. The focus of this paper is on building extraction in urban scenes by means of combined InSAR data and optical aerial imagery.
Characterization of the distribution of water vapour for DInSAR studies on the volcanic island of Tenerife, Canary Islands
Antonio Eff-Darwich, Begoña García-Lorenzo, Juan C. Pérez-Darias, et al.
Measurements of ground displacement have been carried out on the entire active volcanic island of Tenerife, Canary Islands, by means of classical and advanced DInSAR techniques. The main limiting factor on the accuracy of DInSAR measurements is the distribution of the water vapour in the lower troposphere. Hence, it is yet necessary to perform a detailed spatial and temporal characterization of water vapour to understand, and to be able to carry out a direct computation of, the effect of the tropospheric delay on DInSAR results. In this sense, satellite and balloon data have been analysed to infer the variability in the distribution of water vapour and hence, the robustness of DInSAR results on the island of Tenerife.
CovAmCoh-analysis: a method to improve the interpretation of high resolution repeat pass SAR images of urban areas
Karsten Schulz, Markus Boldt, Antje Thiele
The main advantages of SAR (Synthetic Aperture Radar) are the availability of data under nearly all weather conditions and its independence from natural illumination. Data can be gathered on demand and exploited to extract the needed information. However, due to the side looking imaging geometry, SAR images are difficult to interpret and there is a need for support of human interpreters by image analysis algorithms. In this paper a method is described to improve and to simplify the interpretation of high resolution repeat pass SAR images. Modern spaceborne SAR sensors provide imagery with high spatial resolution and the same imaging geometry in an equidistant time interval. These repeat pass orbits are e. g. used for interferometric evaluation. The information contained in a repeat pass image pair is visualized by the introduced method so that some basic features can be directly extracted from a color representation of three deduced features. The CoV (Coefficient of Variation), the amplitude and the coherence are calculated and jointly evaluated. The combined evaluation of these features can be used to identify regions dominated by volume scatterers (e. g. leafed vegetation), rough surfaces (e. g. grass, gravel) and smooth surfaces (e. g. streets, parking lots). Additionally the coherence between the two images includes information about changes between the acquisitions. The potential of the CovAmCoh- Analysis is demonstrated and discussed by the evaluation of a TerraSAR-X image pair of the Frankfurt airport. The method shows a simple way to improve the intuitive interpretation by the human interpreter and it is used to improve the classification of some basic urban features.
Archaeology, Cultural, and Natural Heritage Geospatial Infrastructure I
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Small drones for geo-archaeology in the steppes: locating and documenting the archaeological heritage of the Orkhon Valley in Mongolia
M. Oczipka, J. Bemmann, H. Piezonka, et al.
The international project "Geo-Archaeology in the Steppe - Reconstruction of Cultural Landscapes in the Orkhon valley, Central Mongolia" was set up in July 2008. It is headed by the Department of Pre- and Protohistoric Archaeology of Bonn University. The project aims at the study of prehistoric and historic settlement patterns, human impact on the environment and the relation between towns and their hinterland in the Orkhon valley, Central Mongolia. The multidisciplinary project is mainly sponsored for three years by the German Federal Ministry of Education and Research (BMBF) and bridges archaeology, natural sciences and engineering (sponsorship code 01UA0801C). Archaeologists of the Mongolian Academy of Sciences and of the Bonn University, geographers of Free University Berlin, geophysics of the Institute for Photonic Technology Jena and the RWTH Aachen University, and geographers and engineers of the German Aerospace Centre Berlin collaborate in the development of new technologies and their application in archaeology1. On the basis of Russian aerial photographs from the 1970s, an initial evaluation regarding potential archaeological sites was made. Due to the poor geometric and radiometric resolution of these photographs, identification of archaeological sites in many cases remained preliminary, and detailed information on layout and size could not be gained. The aim of the flight campaign in September 2008 was therefore the confirmation of these sites as well as their high resolution survey. A 10 megapixel range finder camera was used for the recording of high resolution aerial photography. This image data is suited for accurate determination and mapping of selected monuments. The airborne camera was adapted and mounted on an electrically operated eight propeller small drone. Apart from high resolution geo-referenced overview pictures, impressive panoramic images and very high resolution overlapping image data was recorded for photogrammetric stereoscopic processing. Due to the overlap of 85% along and across the track each point in the image data is recorded in at least four pictures. Although a smaller overlap might be sufficient for generating digital surface models (DSM), this redundancy increases the reliability of the DSM generation. Within this photogrammetric processing digital surface models and true ortho photo mosaics with a resolution up to 2,5 cm/pixel in X, Y, Z are derived.
UAV systems for photogrammetric recording in archaeological areas: problems, suggestions, and products
F. Chiabrando, D. Marenchino, F. Nex, et al.
Documentation and measurements on archaeological areas are mostly connected with close-range photogrammetry, in order to analyze the detailed structure of the objects. Classical aerial photogrammetric surveys are expensive and limited by the image resolution. An alternative way is represented by the use of Unmanned Aerial Vehicle (UAV) equipped with photogrammetric sensors. The paper deals with the acquisition and processing of low-height aerial imagery acquired by UAVs, in order to provide large-scale mapping in support of archaeological researches. Two remote controlled systems (one mini helicopter and one mini fixed wing plane) were tested on two different archaeological sites in order to provide Digital Surface Models (DSMs) and large-scale maps (numeric maps and orthophotos). The experimental analyses underline the potentialities and the problems of these systems for photogrammetric surveys. In particular, the UAV image acquisition is far from flights performed by manned planes: their dimensions and their little weights never allow to flight the coarse previously set and, as a consequence, their images are often affected by big rotation and little overlaps. In these conditions, traditional matching algorithms don't always succeed in the generation of reliable DSMs. For this reason, a procedure for the DSM generation in these application field is proposed. It will be shown as this procedure allows satisfying the needs of the archaeological survey in the production of Solid True Ortho-Photos (STOP).
Some effects of the background removal of interest in archaeological GPR prospecting
This contribution deals with the effect of the background removal procedure on GPR data for an inverse scattering algorithm funded on the Born Approximation in the simple case of a scalar two-dimensional geometry. The effect is examined with regard to both the problem of the extraction of scattered field data from the total field data and to the performances of the reconstruction approach. As it will be shown, the background removal amounts to a spatial filtering of the available reconstruction and, depending on the kind of target looked for, it can be very useful but also quite useless or even harmful.
Archaeology, Cultural, and Natural Heritage Geospatial Infrastructure II
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The contribution of high resolution satellite images to the production of base-maps and cartographies for archaeological research in Turkey and Iraq
The paper concerns the contribution of high resolution satellite images to the production of base-maps and cartographies for archaeological research, using both during field work and in GIS dedicated to Cultural Heritage. Particularly, some experiences conducted during researches on Turkish and Iraqi archaeological sites are presented, where the use of satellite images was necessary because of both large scale cartographies and aero-photogrammetrical photos are not available. In the case of archaeological surveys in Hierapolis of Phrygia (south-western Turkey) they provided a fundamental tool for the research on the ground and for the analysis and management of data in the archaeological GIS of the territory. Ikonos-2 and QuickBird-2 images were ortho-rectified with the use of GCPs (taken with a differential GPS) and with DEMs and DSMs processed thanks different remote sensing data, radar (SRTM) and optical (Ikonos-2 and ASTER stereo-pairs), for the creation of space-maps and the extraction of cartographical elements: these (hydrology, modern topography, field boundaries, archaeological remains and traces, etc.) were used with the aims of the creation of new maps for archaeological purpose (the orography was extracted from DEMs) and the update of the existing ones. In the case of some ancient sites studied for the contextualization of the objects showed in the Virtual Museum of Iraq, high resolution images of the same satellites (and of WorldView-1) were ortho-rectified without GPCs and used for the creation or the update of the archaeological maps (generally very old), on which plans of excavated structures, recent discoveries, and archaeological traces and paleo-environmental elements were geo-referenced.
Aerial monitoring and environmental protection: aerial photography as an instrument for checking landscape damage
C.N.R. and University of Salento have realized a Geographical Information System for heritage management of the national territory (landscape) and historical urban settlements. Informations come from bibliography, archives, direct and systematic field survey, different kind of aerial photographs analysis, with the primary aim of knowledge for the establishment of an in existence Cultural Heritage Cadastre, focused to legal protection and exploitation of the sites, not last the correct territory planning.
The use of aerial photographs for studying and planning archaeological parks: the samples of Cerveteri and Veio
Topographical analysis of the territory by field survey, check on site and revision of previous data and pertinent documentation (bibliography, archives, information in loco, etc.), examination and analysis of historical and recent aerial photographs from different archives, monitorig flights on risk areas. Aim: historical sight of territory to create a standard format for legal protection of cultural heritage remains, need of knowledge for the establishment of a global Cultural Heritage Cadastre connected to studies for legal protection and enjoyment of great interest sites; not last the correct territory planning.
Data Fusion
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Fusion of multisource and multiscale remote sensing data for water availability assessment in a metropolitan region
N. B. Chang, Y. J. Yang, A. Daranpob
Recent extreme hydroclimatic events in the United States alone include, but are not limited to, the droughts in Maryland and the Chesapeake Bay area in 2001 through September 2002; Lake Mead in Las Vegas in 2000 through 2004; the Peace River and Lake Okeechobee in South Florida in 2006; and Lake Lanier in Atlanta, Georgia in 2007 that affected the water resources distribution in three states - Alabama, Florida and Georgia. This paper provides evidence from previous work and elaborates on the future perspectives that will collectively employ remote sensing and in-situ observations to support the implementation of the water availability assessment in a metropolitan region. Within the hydrological cycle, precipitation, soil moisture, and evapotranspiration can be monitored by using WSR-88D/NEXRAD data, RADARSAT-1 images, and GEOS images collectively to address the spatiotemporal variations of quantitative availability of waters whereas the MODIS images may be used to track down the qualitative availability of waters in terms of turbidity, Chlorophyll-a and other constitutes of concern. Tampa Bay in Florida was selected as a study site in this analysis, where the water supply infrastructure covers groundwater, desalination plant, and surface water at the same time. Research findings show that through the proper fusion of multi-source and multi-scale remote sensing data for water availability assessment in metropolitan region, a new insight of water infrastructure assessment can be gained to support sustainable planning region wide.
Ameliorating the spatial resolution of Hyperion hyperspectral data
In this study seven fusion techniques and more especially the Ehlers, Gram-Schmidt, High Pass Filter, Local Mean Matching (LMM), Local Mean and Variance Matching (LMVM), Pansharp and PCA, were used for the fusion of Hyperion hyperspectral data with ALI panchromatic data. Both sensors are onboard on EO-1 satellite and the data are collected simultaneously. The panchromatic data has a spatial resolution of 10m while the hyperspectral data has a spatial resolution of 30m. All the fusion techniques are designed for use with classical multispectral data. Thus, it is quite interesting to investigate the assessment of the common used fusion algorithms with the hyperspectral data. The area of study is the broader area of North Western Athens near to Thrakomakedones village.
Interpretability of TerraSAR-X fused data
Pablo H. Rosso, Manfred Ehlers, Sascha Klonus
Pansharpening is an image fusion technique that combines the spatial structure of a high resolution panchromatic image with the spectral information of a lower resolution multispectral image to produce a high resolution multispectral image. Image data of the new German RADAR satellite TerraSAR-X were used to sharpen optical multispectral data. To assess the advantages and limitations of fusion, the interpretability of terrain features at different image resolutions was determined. We concluded that a resolution ratio of 1:10 (TerraSAR:Multispectral) is optimal to benefit from the synergism of a SAR/multispectral fusion. Q index and an object-based classification were used to assess fusion quality and to compare their efficacy to determine the best fusion algorithms. Both approaches are appropriate methods to asses quality but only on judging some aspects of the fusion products. We conclude that a more comprehensive fusion quality assessment method still needs to be developed.
KH-series satellite imagery and Landsat MSS data fusion in support of assessing urban land use growth
Daniel Civco, Anna Chabaeva, Jason Parent
Multi-temporal land use data, circa 1990 and 2000, have been analyzed an our urban growth model which identifies three levels of the urban extent - the impervious surface, the urbanized area, and the urban footprint - to account for the differing degrees of open space degradation associated with the city. The model also generates metrics such as cohesion, proximity, population densities, average openness, open space contiguity, and depth which quantify spatial characteristics that are indicative of urban sprawl. We plan on expanding this time-series further, and for additional cities, with mid-decadal, gap-filled Landsat ETM data, as well as resolution-enhanced Landsat MSS data from the 19070's. The cities used in this pilot project consisted of: (a) Kigali, Rwanda; (b) Portland, Oregon; (c) Tacoma, Washington; and (d) Plock, Poland. Based on research done in this project, complemented by results from other efforts, the Ehlers data fusion approach was used in the resolution enhancement of Landsat MSS imagery. In this paper, using Portland and Kigali as the principal examples, we discuss the procedures by which (a) the KH-series declassified military intelligence imagery was geometrically-corrected and registered to Landsat data, (b) the Ehlers Fusion of the KH-data with Landsat MSS, (c) the derivation of 1970's urban land use information, and (d) the calculation of select urban growth metrics. This paper illustrates the power of leveraging the high resolution of the military reconnaissance imagery with the multispectral information contained in the vintage Landsat MSS data in historical land use analyses.
Geological Remote Sensing
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Rock discrimination and geological mapping of basement rocks at Gabal Gharib area north eastern desert of Egypt with application of landsat ETM and Egyptsat-1 data
Mohamed F. Sadek, Safaa M. Hassan M.D.
Gabal Gharib area comprises Late Proterozoic Precambrian basement rocks of metamorphic and magmatic assemblages uncomfortably overlain by Miocene-Holocene sedimentary rocks. The calc-alkaline metamorphosed volcanic rocks are the main rock varieties forming the exposed metamorphic assemblage extruded by Dokhan volcanics and intruded by syn to late to post tectonic magmatic intrusions of gabbro-diorite, tonalite-granodiorite (G1), monzogranites-alkali feldspar granites (G2) and alkaline riebeckite granites (G3). Different band ratio ETM images, Landsat ETM-Egyptsat-1 fused image data with the spectral signature characterizations together with the data of field study were applied to discriminate these different basement rock units. Four granitic varieties as well as the metamorphosed older volcanics and younger Dokhan-type volcanics are well discriminated. This study revealed that the Landsat ETM- Egyptsat-1 fused band ratio image (7/4, 3/7, 4/5) is the best to discriminate the exposed basement rocks and the structural features at Gabal Gharib area.
Exploration of Wadi Zerka Ma'in rotational fault and its drainage pattern, Eastern of Dead Sea, by means of remote sensing, GIS and 3D geological modeling
Taleb Odeh, Richard Gloaguen, Mario Schirmer, et al.
The Wadi Zerka Ma'in catchment area is located in the North East of the Dead Sea. It contains a confined river of about 23 km length. The region is characterized by a recent sharp base level drop and a strong orographic control on climatic parameters such as temperature and precipitation. It is controlled by three regional structural systems as follow: 1) the anticline - syncline system (late Cretaceous - end of Miocene) which is a part of Syrian fold arc system; 2) NW - SE faults system which were generated simultaneously and parallel to the Red Sea spreading; 3) NWW - SSE faults system which are perpendicular to the Dead Sea and younger than the Red Sea fault system; 4) NNW - SSE faults system (middle Miocene - until now) which were generated simultaneously and parallel to the active Dead Sea transform fault. The structural setting of the study area was evaluated by means of a three-dimensional (3D) geological model, a digital elevation model (DEM) with resolutions 15 meters and stream profile analysis. DEM generation was performed using ASTER data. We found that the Wadi is located at the junction of two main fault systems. The major feature is a trans-tensional fault displacement which changes from 0 to 200 m. We showed that the catchment area is a result of a rotational fault while the river changes its flow direction according to the different fault system directions. The lower portion of the basin is affected by the major base level drops and display contributing rivers in exceptional non-equilibrium. Thus this catchment allows observing the rapid adaptation of the drainage system to both climatic and tectonic forcing.
DSM from ALOS and comparison with airphoto DSM: the case of Thessaloniki, Greece
In this study we compare a DSM created from an ALOS stereo-pair to a DSM created from airphotos stereo-pairs. The area of study is the broader area of Thessaloniki, Greece. After a first control for random or systematic errors a statistical analysis was done. Points of known elevation have been used to estimate the accuracy of the DSMs. The elevation difference between the different DSMs was calculated. 2D RMSE, correlation and the percentile value were also computed and the results are presented.
Hyperspectral fluorescence lifetime lidar for geological exploration
We have developed a small, relatively lightweight and efficient lidar instrument for remotely detecting and classifying minerals. The system is based on a pulsed, eye-safe, diode pumped Nd:YAG laser, tripled (355nm) or quadrupled (266nm), for UV excitation of minerals, which then fluoresce with a typical spectrum and lifetime. Fluorescence is detected through a telescope / filter / fiber bundle / spectrograph / multi-channel detector system capable of photon counting. Transmission and detection efficiency have been optimized to reduce the need for high optical excitation energy. Detection electronics are based on gated charge integration using a multi-anode photomultiplier tube. Spectra shown are measured in the 420 to 720 nm visible range with 355 nm laser excitation. Results show that it is relatively easy to distinguish between vegetation and non-vegetation spectra using lifetime data. Lifetime of vegetation is relatively short when compared to the mineral samples investigated. Although results shown are measured in a controlled environment on the ground, the system is being developed for eventual use in a low altitude airborne application. System parameters are presented and upgrade paths are discussed.
Updating the 1/50.000 geological maps of IGME with remote sensing data, marine geology data, GPS measurements and GIS techniques: the case of KEA Island
Konstantinos G. Nikolakopoulos, Panagiotis I. Tsombos, Dimitrios Mitropoulos, et al.
In this study the combined use of field mapping and measurements, remote sensing data analysis and GIS techniques for the geological mapping of KEA Island at a 1/50.000 scale, is presented. The geological formations, geotectonic units and the tectonic structure were recognized in situ and mapped. Interpretation of high resolution satellite images (Quickbird) and medium resolution satellite images (Landsat 7 ETM and ASTER) has been carried out in order to detect the linear or not structures of the study area. The in situ mapping was enhanced with data from the digital processing of the satellite data. Marine geology data such as bathymetric data and seismic profiles were also taken into account. All the analogical and digital data were imported in a geodata base specially designed for geological data. After the necessary topological control and corrections the data were unified and processed in order to create the final layout at 1/50.000 scale.
Airborne UV/Vis actinic measurements in the lower Antarctic stratosphere
Ivan Kostadinov, Fabrizio Ravegnani, Andrea Petritoli, et al.
The present work deals with UV/Vis up-welling and down-welling irradiation measurements carried out in the lower Antarctic stratosphere by means of GASCOD-A/4pi spectroradiometer on board the M55-Geophysica aircraft during the APE-GAIA campaign. Very few such measurements have been performed in the lower stratosphere. The experimental data are used for the calculation of NO2 photodissociation rate coefficients in the upper troposphere and lower stratosphere along the altitude of the flight. A detailed description of the measurement method, instrumentation and calibration procedures is presented. Experimental results are presented and discussed too.
Environmental Monitoring I
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Remote sensing techniques for mining waste characterization
M. A. Zoran, R. S. Savastru, D. M. Savastru, et al.
Environmental monitoring is essential information routinely required by the mining industry and regulators to demonstrate that the environment is not adversely impacted by exploration and mining. New mining technologies can not only exploit low-grade ores but also produce high volumes of tailings as mining wastes. Satellite remote sensing imagery provided by Landsat TM and ETM sensors is an important investigation tool of mining waste cover screening, mapping and monitoring at local and regional scales of areas containing multiple sources of mining-related heavy metals. By this, satellite remote sensing data can help to rapidly assess the dimension of mining waste risk and therefore better manage such a geohazard as well as for remediation programs. Based on Landsat TM, ETM satellite data over 1989-2007 period, was possible to be achieved a discrimination between weathered materials and other prone to acidification as well as to perform a spatio temporal landcover change detection analysis in some mining waste areas in Maramures County, Romania. Accuracy of image processing results (mineralogical classification) was confirmed through ground sampling and analysis of reflectance spectra with portable GER 2600 spectroradiometer.
Multitemporal land cover pattern change analysis using remote sensing
Katarzyna Ostapowicz, Izabela Sitko
In the paper, we described the methodology enabling automatic land cover pattern change analysis, using satellite data. We relied on the post-classification comparison technique with the classification process based on a supervised approach, joining image segmentation, knowledge-based rules to extract a training set, and the maximum likelihood decision rule on two hierarchical levels. The Polish Carpathians has been studied at a medium scale level, over a period of 19 years (1987-2006). The information about land cover was obtained from Landsat TM and ETM+ images. The overall accuracy received in this approach amounted 88%.
Air pollution monitoring through the application of atmospheric correction for ASTER imagery
This paper presents the results obtained through the application of atmospheric correction on ASTER images for deriving the aerosol optical thickness (AOT). The literature shows that there is a gap in correlating the determined or measured AOT through the visible and near-infrared spectrum with the air-pollutants such as PM10, PM2.5, CO2, etc. This research investigates such aspects by acquiring sun-photometer measurements, image data, and air-pollutants measurements during the satellite overpass of the urban areas in Paphos and Limassol District in Cyprus. AOT values delivered from MODIS satellite images are regressed against the sun-photometer ground-based measurements. The determined AOT values from both sources are compared with the AOT values retrieved from ASTER and/or LANDSAT TM /ETM+ images. Preliminary results show that the AOT retrieved after applying an atmospheric correction from the images was very near to those found from the sun-photometers acquired simultaneous during the satellite overpass.
Development of urban surface models for improved aerosol retrieval
Min Oo, Matthias Jerg, Ana J. Picon, et al.
A combination of CIMEL radiometer and MODIS measurements are used to correct surface albedo models. In particular, we show through an analysis of hyperspectral high resolution Hyperion data that the correlation coefficient assumption underestimates ground albedo resulting in an overestimate of the VIS optical depth and operational collect 5 surface model shows an incorrect trend between the MVI index and the surface correlations. Preliminary radiative transfer calculations based on the same model show that this mechanism can help explain the observed overestimation and the corrected models have been implemented for NYC and Mexico City with significantly improved AOD.
Environmental Monitoring II
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Remote sensing satellite constellation for world-wide wild fire monitoring
David A Bennett, Raymond M. Bell, Douglas B. Helmuth, et al.
Satellite remote sensing can provide continuous surveillance to detect, characterize, and map wild fires, agricultural fires, and land management fires. Fire management challenges require additional capability to allow rapid revisit rates, rapid tasking, and data delivery to the field sufficient for fire management agencies in modern and developing nations worldwide. An analysis and description of the required constellation of satellites and sensors is given with consideration of tasking and data delivery.
Environmental monitoring of Galway Bay: fusing data from remote and in-situ sources
Edel O'Connor, Jer Hayes, Alan F. Smeaton, et al.
Changes in sea surface temperature can be used as an indicator of water quality. In-situ sensors are being used for continuous autonomous monitoring. However these sensors have limited spatial resolution as they are in effect single point sensors. Satellite remote sensing can be used to provide better spatial coverage at good temporal scales. However in-situ sensors have a richer temporal scale for a particular point of interest. Work carried out in Galway Bay has combined data from multiple satellite sources and in-situ sensors and investigated the benefits and drawbacks of using multiple sensing modalities for monitoring a marine location.
Environmental Monitoring III
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Applications of Terra MODIS data for Iraq marshland monitoring
Francesca Despini, Sergio Teggi, Lorenza Bovio, et al.
Since the 1970s, the Iraq Marshlands have been damaged significantly, but recently (May 2003-March 2004), more than 20% of the original marshland area has been re-flooded. The goal of the work is to observe the evolution of the marshes in terms of extension and to evaluate the success of wetland restoration on the base of multispectral and multitemporal MODIS images collected in 2007-2008. MODIS (MODerate resolution Imaging Spectroradiometer) has a viewing swath width of 2,330 km and views the entire surface of the Earth every one to two days. Its detectors measure 36 spectral bands between 0.405 and 14.385 μm, and it acquires data at three spatial resolutions -- 250m, 500m, and 1,000m. These data with their low spatial resolution but high time frequency are suitable for regional-scale time-series studies. The satellite data have been corrected for atmospheric effects using an IDL (Interactive Data Language) procedure based on MODTRAN and 6S radiative transfer codes. These radiative transfer codes require, in input, atmospheric vertical profiles, aerosol optical thickness(AOT) and columnar water vapour content (WV). Vertical profiles are obtained from the nearest meteorological station or by climatological data set. AOT and WV are retrieved either from the MODIS MODATML2 atmospheric product, or from the AERONET (Aerosol robotic network). Then different classifications (Pixel- and Object-Oriented) have been tested, compared and discussed to evaluate the best approach to apply on regional-scale time-series studies.
Water stress monitoring using NDWI around deserts of China and Mongolia
The fluctuation of vegetation water condition around desert area is one of most important parameters to interpret the desertification expansion. United Nations reported that about 35 million square kilometers of land are subject to desertification. Historically, many parts of China have been suffered from severe desertification. This paper attempts an analysis for spatio-temporal variation characteristics of vegetation drought status around China and Mongolia desert with remotely sensed data. Time series images (1 January, 1999 - 31 December 2006) obtained from SPOT/VEGETATION were used to monitor inter-annual variability of water condition. SPOT/VEGETATION satellite, which has a fine temporal resolution and sensitive to vegetation growth, could be very useful to detect large scale dynamics of environmental changes and desertification progress. The main objective of the study is analyzing water status around China and Mongolia desert and predicting a risk area of desertification. In this study, NDWI (Normalized Difference Water Index) is used to monitor vegetation water condition (drought status) over the study area. To interpret the relationship between vegetation drought status and vigor, NDVI (Normalized Difference Vegetation Index) was employed in ensemble with NDWI. Annual total precipitation from NCEP/NCAR reanalysis data is used as subsidiary data. The study area from 73°36´E to 120°41´E longitude and from 30°81´N to 52°13´N longitude in northern China and whole Mongolia. NDWI value around desert has a range from -0.05 to -0.35 and NDWI values are decreased during the study period. Each year precipitation patterns are similar to yearly mean NDWI value. The study detected several areas where NDWI is dramatically decreased for 8 years, especially northeast part of Mongolian Gobi desert and southeast part of China Taklamakan desert.
Urban Remote Sensing
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The effectiveness of morphology and street networks in determining models of urban growth at different spatial scales of analysis
Urban morphology "implies 'form,' 'land use,' and 'density,' and has connotations with the shape, structure, pattern and organization of land use, and the system of relation between them" (Donnay, Barnsley, and Longley, 2001). It reflects the combination of complex special artificial areas such as buildings, roads, parks, gardens and even ecological systems of soil and water. To understand the dynamics and patterns of urban extend related with their interactions in heterogeneous landscapes, the spatial complexity needs to be quantified accurately, depending upon the morphological analysis and their relation with territory. Morphological analysis, which refers to the geometric characteristics of urban sites, illustrates its usefulness in determining the analogies between patterns of cities and their "physical" characters providing indicators of the aspect of settlement form and structure. Remote sensing might be helpful on the regional scale in evaluating the role that landscape play in connecting different settlements within urban regions and in separating the core city from the surrounding countryside. It used to map urban morphology of human settlements and monitoring urban growth (Batty and Longley, 1987). The information produced by remote sensing is spatially referenced through an implicit geometric location of the pixels. Various urban forms are potentially discernible using such devices, including linear objects (Sohn and Bowman, 2001). The aim of this paper is to classify, evaluate and compare different urban forms related to street networks and land characters, also considering the morphological typologies of urban settlements by moving from the spatial scale of a municipality to a wider territorial. The intent is to discover secure principals to find the most likely urban models of cities, taking topographical parameters into account. This research carried out focusing upon the metropolitan region of Barcelona, with urban sites defined according to the contiguity of artificial and administrative boundaries. The TeleAtlas and land activity classification deriving from Spot Imagery form the basis of this study. We will focus on the development of a methodology to classify the geometric properties and intrinsic space of urban settlements based on their characteristics and fundamental forms.
Urban landcover mapping using different spectral mixture analysis methods
L. F. V. Zoran, C. Ionescu Golovanov, M. A. Zoran
The complex spatial and spectral variability of urban structures present fundamental challenges to deriving accurate remote sensing information for urban areas. Spectral mixture analysis (SMA), based on a physical mixture model, has ability to extract sub-pixel information such as the abundances of each endmember presented in the pixel (image unity). In this paper, different spectral mixture methods have been applied in order to examine the performance of each model in dealing with spectral variability of urban surface. The comparison is focused on linear spectral mixture analysis (LSMA) which is using a fixed number of endmembers for the entire scene and multiple endmember spectral mixture analysis (MESMA) which allows the number and types of endmembers to vary from pixel to pixel to extract the abundances of urban surface components. These techniques have been applied to map the physical components of urban land cover for the city of Bucharest, Romania, using Landsat Thematic Mapper (TM), Enhanced Thematic Mapper (ETM+) and IKONOS imagery for 1989 - 2007 period. This paper demonstrates the potential of moderate-and high resolution, multispectral imagery to map and monitor the evolution of the physical urban environment.
Environmental Monitoring IV
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Monitoring coastal water quality in a municipal beach in Paphos-Cyprus using ASTER image data and spectral signatures
Hadjimitsis G. Diofantos, Hadjimitsis G. Marinos, Agapiou Athos, et al.
Using remote sensing data to assess the quality of water bodies has proven to be successful not only in inland waters but to coastal water areas as shown by several others conducted studies. The main objective of this study is to use ASTER data to evaluate the potential of using such remotely sensed digital data, to extract information that help in the monitoring system for Cyprus coastal water quality, especially in municipal beaches that are included in the Blue Flag Programme. Reflectance signature of municipal coastal water is monitored using a GER 1500 field spectroradiometer. Simultaneous measurements of turbidity, temperature have been acquired. E-coli values have been retrieved through the sampling procedure. Such coastal water quality assessment can assist the Blue-Flag Programme in the area under investigation. ASTER images can be programmed for summer acquisitions in which Blue-Flag Programme is active so this can be considered an advantage and can be used by the local authorities as a systematic monitoring tool. It has been found after correlating the SS, Turbidity with the water reflectance obtained using the GER 1500 that high correlation was occurred for the wavelength region that corresponds to ASTER band 2 and band 3 respectively (r2>0.80 ). Temporal and spatial variations can be monitored from satellite images as shown from the in-situ validated spectroradiometric measurements.
Monitoring vegetation dynamics with SPOT-VEGETATION NDVI time-series data in Tarim Basin, Xinjiang, China
Desertification in the arid and semiarid regions directly influences the density and growth status of vegetation, NDVI (Normalized Difference Vegetation Index) has been widely used to monitor vegetation changes. This study analyzed the spatial patters of vegetation activity and its temporal variability in Tarim Basin, Xinjiang, China since 1998 to 2007 with NDVI data derived from SPOT4 Vegetation. The coefficient of variation (CoV) of the NDVI was used as a parameter to characterize the change of vegetation and to compare the amount of variation in different sets of sample data. The method of quantifying changes in CoV values for each pixel was based on linear regression. The slope of linear regression was acted as the criterion for the change direction: pixels with a negative slope are considered to represent ground area with decreasing amounts of vegetation, vice versa. In this paper, We calculated (1) the inter-annual CoV based on the yearly ONDVI, the sum of the monthly NDVI in the growing season (from April to October), for each pixel between 1998-2007 to reveal the spatial patterns of vegetation activity, (2) the intra-annual CoV based on monthly NDVI by MVC to reflect vegetation seasonal dynamics, (3) the slope (ê) of the intra-annual CoV regression line for each pixel to identify the overall long-term trend of vegetation dynamics. This experiment demonstrated the feasibility of applying the CoV and its regression analysis based on long term SPOT-VGT NDVI time-series data for vegetation dynamics monitoring.
Environmental Monitoring V
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Remote sensing and GIS based study of potential erosion and degradation areas on the island Fogo (Cape Verde Islands)
The Island of Fogo (Cape Verde) is affected by processes of erosion and degradation, caused mainly by a high population growth and global change. With its small scaled climatic, floristic and geo-ecological differentiation, the island of Fogo is an optimal research space for understanding semiarid island ecosystems in the marginal tropics and their behaviour to erosion and degradation processes. For that reason, a change detection analysis over the past two decades is generated, showing the level and direction of land cover and land use change. Two satellite images from 1984 and 2007 will classified by a Maximum Likelihood approach. In a further step, an image of 1974 will be also integrated in this change detection analysis, enlarging the study over the last three decades.
GIS application for spatial landslide analysis using statistical based models
Biswajeet Pradhan, Saro Lee, Manfred F. Buchroithner
This paper presents the assessment results of spatially based probabilistic three models using Geoinformation Techniques (GIT) for landslide susceptibility analysis at Penang Island in Malaysia. Landslide locations within the study areas were identified by interpreting aerial photographs, satellite images and supported with field surveys. Maps of the topography, soil type, lineaments and land cover were constructed from the spatial data sets. There are ten landslide related factors were extracted from the spatial database and the frequency ratio, fuzzy logic, and bivariate logistic regression coefficients of each factor was computed. Finally, landslide susceptibility maps were drawn for study area using frequency ratios, fuzzy logic and bivariate logistic regression models. For verification, the results of the analyses were compared with actual landslide locations in study area. The verification results show that bivariate logistic regression model provides slightly higher prediction accuracy than the frequency ratio and fuzzy logic models.
Airborne and High Resolution Remote Sensing I
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Airborne camera and spectrometer experiments and data evaluation
F. Frank Lehmann, T. Bucher, S. Pless, et al.
New stereo push broom camera systems have been developed at German Aerospace Centre (DLR). The new small multispectral systems (Multi Functional Camerahead - MFC, Advanced Multispectral Scanner - AMS) are light weight, compact and display three or five RGB stereo lines of 8000, 10 000 or 14 000 pixels, which are used for stereo processing and the generation of Digital Surface Models (DSM) and near True Orthoimage Mosaics (TOM). Simultaneous acquisition of different types of MFC-cameras for infrared and RGB data has been successfully tested. All spectral channels record the image data in full resolution, pan-sharpening is not necessary. Analogue to the line scanner data an automatic processing chain for UltraCamD and UltraCamX exists. The different systems have been flown for different types of applications; main fields of interest among others are environmental applications (flooding simulations, monitoring tasks, classification) and 3D-modelling (e.g. city mapping). From the DSM and TOM data Digital Terrain Models (DTM) and 3D city models are derived. Textures for the facades are taken from oblique orthoimages, which are created from the same input data as the TOM and the DOM. The resulting models are characterised by high geometric accuracy and the perfect fit of image data and DSM. The DLR is permanently developing and testing a wide range of sensor types and imaging platforms for terrestrial and space applications. The MFC-sensors have been flown in combination with laser systems and imaging spectrometers and special data fusion products have been developed. These products include hyperspectral orthoimages and 3D hyperspectral data.
A modular, interactive software-concept for radiometric and geometric correction of airborne and spaceborne linescanner images
To generate ortho photos and terrain models from airborne and spaceborne linescanner images, various complex radiometric and geometric corrections have to be applied to the raw images. In this contribution a software-concept is presented, that allows the configuration and application of a modular and expandable chain of such corrections through an interactive graphical user interface. The effect of any changed correction parameter is visualized immediately in zoomable preview-windows. Different correction-steps are illustrated with respect to the generation of terrain models with Semi-Global Matching (SGM), including radiometric sensor and atmosphere correction, as well as sensor boresightalignment calculation and aerotriangulation.
Solutions for near real time cartography from a mini-quadrators UAV
A. Gademer, F. Mainfroy, L. Beaudoin, et al.
In this article, we present another way to acquire centimetric data using a quad-rotor UAV and the specific tools developed to perform near real time cartography. After setting the context of the UAVs, we will present the design and the realization of our quad-rotor Vertical Take Off and Landing solution and it's capacity for Very High Resolution imagery. Then we will describe the tools we developed to improve its ability for operational mapping : how to perform flight in immersion with a customizable HUD that takes the video broadcast from the UAV and adds vector information in real-time on virtual reality goggles, how to combine satellite and vector data with path optimization algorithm to design relevant flight plans and update them in real time to ensure data completeness, how to generate relevant geolocalization meta-data to be able to navigate in the produced image database few minutes after the landing and finally, how to employ home-made open-source mosaicer to take advantage of the three simultaneous on-board digital camera.
Airborne and High Resolution Remote Sensing II
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Vulnerability assessment towards tsunami threats using multisensoral remote sensing data
Hannes Taubenböck, Michael Wurm, Joachim Post, et al.
The occurrence of a tsunami, a set of oceans waves caused by any large, abrupt disturbance of the sea surface, hitting a vulnerable system on land can cause massive loss of life, destruction of coastal infrastructure and disruption of economic activity. Vulnerability assessment and risk modelling are important components for an effective end-to-end hazard early warning system and therefore contribute significantly to disaster risk reduction. The focus of this study is on the capabilities and synergistic usage of multisensoral remotely sensed data to contribute to these complex tasks. We use medium and high resolution optical satellite data (Landsat and Ikonos), high resolution radar data from TerraSAR-X as well as a digital elevation model to provide multiple products for the assessment of spatial vulnerability in case of a tsunami impact on the heterogeneous and highly structured coastal urban area of Padang, Indonesia. Results include physical indicators like dimension and location of urbanization, quantification of potentially affected buildings, the identification of safe areas as well as a time-dependent population assessment.
Derivation of population distribution for vulnerability assessment in flood-prone German cities using multisensoral remote sensing data
Michael Wurm, Hannes Taubenböck, Susanne Krings, et al.
Against the background of massive urban development, area-wide and up-to-date spatial information is in demand. However, for many reasons this detailed information on the entire urban area is often not available or just not valid anymore. In the event of a natural hazard - e.g. a river flood - it is a crucial piece of information for relief units to have knowledge about the quantity and the distribution of the affected population. In this paper we demonstrate the abilities of remotely sensed data towards vulnerability assessment or disaster management in case of such an event. By means of very high resolution optical satellite imagery and surface information derived by airborne laser scanning, we generate a precise, three-dimensional representation of the landcover and the urban morphology. An automatic, object-oriented approach detects single buildings and derives morphological information - e.g. building size, height and shape - for a further classification of each building into various building types. Subsequently, a top-down approach is applied to distribute the total population of the city or the district on each individual building. In combination with information of potentially affected areas, the methodology is applied on two German cities to estimate potentially affected population with a high level of accuracy.
Classification - Evaluation
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From fuzzy and object based classification to fuzzy and object based uncertainty evaluation
Jochen Schiewe, Manfred Ehlers, Christoph Kinkeldey, et al.
Regarding thematic processing of remote sensing data new problems have arisen with the rapid increase of geometric and spectral resolution. These have been partly solved through the application of object oriented methods and alternative (e.g. fuzzy logic) approaches for the actual allocation of a feature to a topographical object whereas these methods do not apply comprehensively to the quality assessment of the processed data. We present an integrated approach for the assessment of classified high-resolution remote sensing scenes which considers uncertainties - not only in the classified data but in the reference ("ground truth") data as well. Instead of discrete object boundaries we define transition zones between adjacent objects; a fuzzy function describes the distribution of class membership values within these zones. Thus we can compute an evaluation measure on the basis of the uncertainty model - the CFCM (Class-specific Fuzzy Certainty Measure) provides a quality assessment for classified remote sensing data considering uncertainties in geometry and semantics. The work is part of the project "CLassification Assessment using an Integrated Method (CLAIM)".
Fuzzy segmentation for geographic object-based image analysis
Image segmentation partitions remote sensing images into image objects before assigning them to categorical land cover classes. Current segmentation methods require users to invest considerable time and effort in the search for meaningful image objects. As an alternative method we propose 'fuzzy' segmentation that offers more flexibility in dealing with remote sensing uncertainty. In the proposed method, original bands are processed using regression techniques to output fuzzy image regions which express degrees of membership to target land cover classes. Contextual properties of fuzzy regions can be measured to indicate potential spectral confusion. A 'defuzzification' process is subsequently conducted to produce the categorical land cover classes. This method was tested using data sets of both high and medium spatial resolution. The results indicate that this approach is able to produce classification with satisfying accuracy and requires very little user interaction.
The analysis accuracy assessment of CORINE land cover in the Iberian coast
Corine land cover 2000 (CLC2000) is a project jointly managed by the Joint Research Centre (JRC) and the European Environment Agency (EEA). Its aim is to update the Corine land cover database in Europe for the year 2000. Landsat-7 Enhanced Thematic Mapper (ETM) satellite images were used for the update and were acquired within the framework of the Image2000 project. Knowledge of the land status through the use of mapping CORINE Land Cover is of great importance to study of interaction land cover and land use categories in Europe scale. This paper presents the accuracy assessment methodology designed and implemented to validate the Iberian Coast CORINE Land Cover 2000 cartography. It presents an implementation of a new methodological concept for land cover data production, Object- Based classification, and automatic generalization to assess the thematic accuracy of CLC2000 by means of an independent data source based on the comparison of the land cover database with reference data derived from visual interpretation of high resolution satellite imageries for sample areas. In our case study, the existing Object-Based classifications are supported with digital maps and attribute databases. According to the quality tests performed, we computed the overall accuracy, and Kappa Coefficient. We will focus on the development of a methodology based on classification and generalization analysis for built-up areas that may improve the investigation. This study can be divided in these fundamental steps: -Extract artificial areas from land use Classifications based on Land-sat and Spot images. -Manuel interpretation for high resolution of multispectral images. -Determine the homogeneity of artificial areas by generalization process. -Overall accuracy, Kappa Coefficient and Special grid (fishnet) test for quality test. Finally, this paper will concentrate to illustrate the precise accuracy of CORINE dataset based on the above general steps.
Geostatistical regularization of inverse models for the retrieval of vegetation biophysical variables
C. Atzberger, K. Richter
The robust and accurate retrieval of vegetation biophysical variables using radiative transfer models (RTM) is seriously hampered by the ill-posedness of the inverse problem. With this research we further develop our previously published (object-based) inversion approach [Atzberger (2004)]. The object-based RTM inversion takes advantage of the geostatistical fact that the biophysical characteristics of nearby pixel are generally more similar than those at a larger distance. A two-step inversion based on PROSPECT+SAIL generated look-up-tables is presented that can be easily implemented and adapted to other radiative transfer models. The approach takes into account the spectral signatures of neighboring pixel and optimizes a common value of the average leaf angle (ALA) for all pixel of a given image object, such as an agricultural field. Using a large set of leaf area index (LAI) measurements (n = 58) acquired over six different crops of the Barrax test site (Spain), we demonstrate that the proposed geostatistical regularization yields in most cases more accurate and spatially consistent results compared to the traditional (pixel-based) inversion. Pros and cons of the approach are discussed and possible future extensions presented.
Environmental Monitoring VI
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Multi-temporal airborne remote sensing of intertidal sediment dynamics
Coastal remote sensing applications are regularly confined to single image 'snapshot' approaches which do not resolve the dynamic processes in the required temporal resolution. This paper reports the results of a project in which the dynamics of tidal sedimentation were monitored by multi-temporal airborne remote sensing in 10 minute time steps. The radiance data was then converted to estimates of suspended particulate matter loading by the inversion of a hydro-optical analytical model. The results demonstrate that multi-temporal coastal remote sensing can provide information about such dynamic processes that realistically can not be obtained by field-based research methods.
Cruise ships flow rate emission evaluated by means of a passive DOAS instrument
The emissions of the cruise ships, in terms of nitrogen dioxide (NO2) and sulphur dioxide (SO2), are evaluated with the DOAS scanning spectrometer TropoGAS (Tropospheric Gas Analyser Spectrometer) developed at ISAC CNR in close collaboration with the CGE-UE. The slant columns amounts of the above mentioned compounds are obtained with the application of the Differential Optical Absorption Spectroscopy (DOAS) technique to the spectral measurements carried out with the TropoGAS instrument. This last is linked with an optical fibre to a simple scanning optical system allowing for measurements in multiple axis configurations. The measurements are carried out across the Giudecca Channel in Venice, during two field campaigns performed in July and in October 2007. The instrumental setup, the DOAS method and the technique for the evaluation of the ships emissions, are described. The results of flow rate emissions for NO2 and SO2 are presented and discussed. Their mean values are about 12g/s and 4 g/s for NO2 and SO2 respectively.
Poster Session
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Analyses of forest fire danger based on remote sensing in subtropical monsoon zone
Shu-e Huang, Jinxiang Xiao, Ning Zhao, et al.
The paper analyses seasonal changes of spectral characteristics values of satellite remote sensing when the forest fire was happening during the season of forest fire prevention. Based on the seasonal change characteristics and spectral characters of polar satellite bands, the forest hotspot was identified by using several infrared bands, and based on the combination-spectral expression of mid-infrared and thermal-infrared channel, the spectral threshold would be established for monitoring forest fire in different forest growing season in subtropical monsoon zone.
Fusion of Landsat TM and ground spectrometry data in monitoring of non-operating mine
Surface mining activities in Europe are estimated to cover an area of 5-10 000 km2. In this paper we suggest that the availability of Landsat Thematic Mapper (TM) for Earth observation allows the collection of environmental and minerelated data for use in the planning and undertaking of mine restoration work on cost-effective basis. The advantage is that these data are acquired digitally and can be easily processed and utilized in various information formats. Important step in the data processing is the verification of airborne data. For this purpose ground spectrometry measurements of samples taken from test sites have been performed. In the last decade several mining areas and corresponding dumps are subject to reclamation process in Bulgaria. We focused our research on one of the most important in the copper production for 20 year period for our country - Asarel-Medet deposit. This mining complex consists of an open mine, the dumps and a processing plant. After ceasing the exploitation of Medet deposit in 1994 a rehabilitation program for soil cover and hydrographic network was established and launched. A continuous task is the monitoring of these activities from the beginning for at least 15 years period, which is to end this year. To process the data, which characterize the progress of the land cover restoration, several techniques, both standard, such as basic and advanced statistics, image enhancement and data fusion, and novel methods for supervised classification were used. The results obtained show that used data and the implemented approach are useful in environmental monitoring and are economically attractive for the company responsible for the ecological state of the region.
Morphological and lithological aspects in the northeastern Libyan desert by remote sensing
G. Bitelli, P. V. Curzi, E. Mandanici
A multi-scale/multi-sensor approach has been applied on a portion of the Libyan Desert in Egypt, providing a morphological and lithological setting. Large depressions are the main geomorphological structure, as evidenced by DTMs created by satellite and topographical data. Bare soils are well exposed over the largest part of the area: a spectral analysis, performed on multispectral MODIS and ASTER images, has allowed the recognition of the major lithological units. The classification is a starting point for further investigations, towards a better understanding of the mutual influence between landscape and human settling during historical time.
Modeling techniques for gaining additional urban space
One of the major accompaniments of the globalization is the rapid growing of urban areas. Urban sprawl is the main environmental problem affecting those cities across different characteristics and continents. Various reasons for the increase in urban sprawl in the last 10 to 30 years have been proposed [1], and often depend on the socio-economic situation of cities. The quantitative reduction and the sustainable handling of land should be performed by inner urban development instead of expanding urban regions. Following the principal "spare the urban fringe, develop the inner suburbs first" requires differentiated tools allowing for quantitative and qualitative appraisals of current building potentials. Using spatial high resolution remote sensing data within an object-based approach enables the detection of potential areas while GIS-data provides information for the quantitative valuation. This paper presents techniques for modeling urban environment and opportunities of utilization of the retrieved information for urban planners and their special needs.
Monitored landscape change of Lake Baiyangdian wetland with dynamic reed area based on remote sensing
Zhen Wang, Lei He, Shengwei Zhang, et al.
Lake Baiyangdian, a largest wetland ecosystem in North China Plain, has dried up on seven occasions since the 1960s. In recent years, more than one billion of cubic meters of water from upstream reservoirs and Yellow river have been transported to the lake to rescue the shrinking wetlands. Since the Lake Baiyangdian was actually composed of 143 small lakes and more than 70 villages with large or small area of cropland, dynamic distribution of aquatic plants in wetland such as reed and associated growth condition of these allowed to monitor the changes of wetland landscape and water quality to support the policy applications of water conveyance and wetland environmental treatment and control. Assisted with ground survey analyses and Landsat TM image, the MODIS 250 m time series Normalized Difference Vegetation Index (NDVI), given its combination of medium spatial and high temporal resolution, were applied to detect the unique rapid growth stage of reed in the spring from adjacent crops such as winter wheat, cotton, and spring maize, of which has a similar phenology in development of leaf area index, and dynamic reed areas were mapped in recent decade. Landscape changes of the wetland were analyzed using maps of reed area and hydrological data.
East-Asia land surface emissivity maps generated from Terra/ASTER data archives
Hideyuki Tonooka, Minoru Urai
The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a high-spatial-resolution multispectral imager on the Terra satellite launched in December 1999. The ASTER thermal infrared (TIR) subsystem has five spectral bands with a spatial resolution of 90 m in the TIR spectral region, which are used for generation of the standard products of surface temperature and surface spectral emissivity. High-resolution surface emissivity at five spectral bands is unique, and is particularly useful for geological mapping. However, the emissivity product is not always easy to use, because (1) its image size is about 60 km square which is not large enough for regional-scale studies, (2) its imaged area is not fixed to the world reference system (WRS) due to a flexible pointing system, and (3) standard atmospheric correction often fails under humid conditions. Thus, in order to improve the usability of the ASTER emissivity product, we are generating land surface emissivity maps in a regional scale by applying improved retrieval algorithms and stack/mosaic processing to an ASTER orthogonal projection dataset which have been produced from the ASTER data archives by the Advanced Industrial Science and Technology (AIST), Japan. In the present paper, we introduce East-Asia land surface emissivity maps as the first result of this project. A comparison study with MODIS monthly emissivity products (MOD11C3) indicates that the generated maps give more reasonable emissivity spectra with higher spatial resolution than the MODIS emissivity products, though the maps have missing pixels in high latitude areas and humid areas.
Monitoring of geological activity on astronomical sites of the Canary Islands, Hawaii, and Chile
Future large and extremely large ground-based telescopes will demand stable geological settings.Remote sensing could be an unvaluable tool to analyse the impact of geological activity at selected astronomical sites, namely the observatories of El Teide (Tenerife, Canary Islands), Roque de los Muchachos (La Palma, Canary Islands), Mauna Kea (Hawaii) and Paranal (Chile) and the candidate site of Cerro Ventarrones (Chile). In this sense, the extent of lava flows, eruptive clouds or ground deformation associated to seismic and/or volcanic activity could be analysed and characterised through remote sensing.
A study of forest fire danger district division in Lushan Mountain based on RS and GIS
Jinxiang Xiao, Shu-E Huang, Anjian Zhong, et al.
The study selected 9 factors, average maximum temperature, average temperature, average precipitation, average the longest days of continuous drought and average wind speed during fire prevention period, vegetation type, altitude, slope and aspect as the index of forest fire danger district division, which has taken the features of Lushan Mountain's forest fire history into consideration, then assigned subjective weights to each factor according to their sensitivity to fire or their fire-inducing capability. By remote sensing and GIS, vegetation information layer were gotten from Landsat TM image and DEM with a scale of 1:50000 was abstracted from the digital scanned relief map. Topography info. (elevation, slope, aspect) layers could be gotten after that. A climate resource databank that contained the data from the stations of Lushan Mountain and other nearby 7 stations was built up and extrapolated through the way of grid extrapolation in order to make the distribution map of climate resource. Finally synthetical district division maps were made by weighing and integrating all the single factor special layers,and the study area were divided into three forest fire danger district, include special fire danger district, I-fire danger district and II-fire danger district. It could be used as a basis for developing a forest fire prevention system, preparing the annual investment plan, allocating reasonably the investment of fire prevention, developing the program of forest fire prevention and handle, setting up forest fire brigade, leaders' decisions on forest fire prevention work.
Detecting the change of Lianyungang during the period of 1987-2007 using remote sensing
Lianyungang is one of the first 14 Chinese coastal cities opening to the outside world in 1984, she had developed about 20 years and has many changes in urban size or structure. And remote sensing has been an important technology for monitoring city development and growth. So, this paper presented the developments and growths of Lianyungang using TM data. Through the processing of three years TM data of 1987, 2000 and 2007 and extraction of urban information, the results showed that three districts and four countries of Lianyungang had great change in size and shape. The results showed that the changes of all county urban scale was relatively small from 1987 to 2000, and rapid sprawled from 2000 to 2007; and they sprawled in different direction. The counties except Lianyungang city had the same development pattern which was centered on old city zone and spread to the surrounding area. The development mode of Lianyungang city was different with them. It was a ribbon mode from west to east, namely from Haizhou, Xinpu districts to Lianyun districts. The status of developments of all districts and counties was related to the needs of economic development, traffic, policy and so on. At present Lianyungang obtains a lot of attention and support from the state and Jiangsu Province, and has changes everyday.
Detection of land-cover and land-use change in the Hohe Tauern National Park (Austria) using an object-based classification approach: first results
Katharina Kern, Wolfgang Sulzer, Gerhard K. Lieb
Land-cover and land-use (LCLU) change reflects environmental as well as social changes. High-mountain environments such as the Hohe Tauern Range (Austria) and its National Park are very sensitive to these changes. Remotely sensed data are ideally suited to detect and analyze land-cover and land-use changes on different spatial and temporal scales. In this study a Landsat Thematic Mapper (TM) time-series from 1988 to 2003, aerial photographs and auxiliary GIS data were used detect land-cover and land-use changes in the National Park and its surroundings. The objective of the study was to develop and test a transferable method for change detection in comparable high-mountain environments. After applying a series of pre-processing steps, object-based image analysis, on the basis of Definiens Developer, was used to extracted land-cover and land-use information from the Landsat images. To generate meaningful image objects, a multiresolutions segmentation algorithm was combined with image object merging. The resultant image objects were then classified by using a hierarchically organized classification method. In a further step the resultant outputs of the land-cover and landuse classifications build the basis for the post-classification change detection. Moreover the advantages and disadvantages of the developed method, the first results as well as future adaptations of the method and applications are discussed in this paper.
Research on the dynamic change of ecosystem benefits in Hangzhou Xixi wetland based on Citygreen model and remote sensing
Based on TM images of Hangzhou Xixi wetland, two different time classified images were obtained. By using the type of landscape assessment of ecosystem benefit based on City green model and GIS, the Dynamic Change of Ecosystem Benefits in Hangzhou Xixi wetland from 1991 to 2005 was researched. Through the changed table for unit area kind of changing ecological benefit, as well as through the comprehensive analysis of various broad headings area data and the unit ecological benefit of Hangzhou Xixi wetland from 1991 to 2005, the ecology service value in Hangzhou Xixi wetland of the two times respectively were calculated. The results show that the ecology service value in 1991was 80.983 million Yuan, and the ecology service value in 2005 was 46.031million Yuan. It indicated that from 1991 to 2005, the total ecology service value in Hangzhou Xixi wetland's was at a drop condition, the value of declination was 107.888 million Yuan.
Beach hydromorphological classification through image classification techniques applied to remotely sensed data
A. C. Teodoro, J. Pais-Barbosa, F. Veloso-Gomes, et al.
Evaluation of beach hydromorphological behavior and its classification is extremely complex. Several aerial photographs, using visual interpretation on a GIS environment, were previously used on the identification of coastal hydroforms and hydromorphologies, and to classify beach morphological stage in a selected area of the NW Portuguese coast. The goal of this study is to improve and develop new methodologies to identify coastal features and coastal patterns. In order to achieve that, pixel-based classification and object-oriented classification algorithms were employed, with the aim to identify and analyze morphological features and hydrodynamic patterns and to compare these results with the visual interpretation already performed. The dataset is composed by two aerial photographs (1996 and 2001) and one IKONOS-2 image (2004). The supervised classification algorithms presented good results both for aerial photographs and for IKONOS-2 image, demonstrated by its overall accuracy and Kappa coefficient values. For the two aerial photographs the best results were found for the maximum likelihood classifier and for the IKONOS-2 image the best result was archived with the parallelepiped classifier. The object-oriented classification performance for the aerial photographs was very good, identifying the classes of interest. The results obtained with the IKONOS-2 image were worst.
Algorithm for image fusion based on DEM and remote sensing image
Terrain roughness and vegetation growth are important influence factors of environment. But it is very difficult to describe the terrain roughness in remote sensing image. Although with the launch of TERRA, Moderate resolution Imaging Spectroradiometer (MODIS), with abundant information, quickly acquiring data and wide range of coverage, is a new data for classication of land area. Considering terrain is still very important problem. This study considered the characteristics of Zhejiang land planting. The digital slope image derived from the DEM map and multitemporal MODIS were used for the purpose of improving the classification accuracy of MODIS in large hilly region. Two methods have been employed till now. One is visual interpretation using digital images. and the other is the automated extraction of landform characteristics from DEM. Thus, the results obtained from the first method are difficult for future use. As to the second method, it is difficult to get detailed classifications for example. to distinguish a valley plain from an open plain by using DEM alone due to the complex nature in landform characteristics. In fact, DEM and digital image contain different yet complementary information related to landform features Therefore a new method to integrate landform information of both DEM and MODIS and NOAA-AVHRR image by digitizing signing lines in MODIS and NOAA-AVHRR image is presented in this paper. With this approach different results of basic landforms were successfully classified and mapped automatically in Zhejiang Province In addition the spatial variability of accuracy in classification was also evaluated by sampling points based on an application of Globe positioning system (GPS).
The impact study of urban heat island effect caused by surface land use changes
Tien-Yin Chou, Lung-Shih Yang, Chih-Hung Liu, et al.
Urban heat island (UHI) effect can be characterized by increasing surface and atmospheric temperature and decreasing rainfall amount in urban area. This research detected the impact of urban land use changes to UHI effect in Taichung city at Taiwan by temporal ASTER and MODIS satellite images and measured data from ground thermometer stations. From spatially analyzed data output, the results showed a linear pattern between land use changes to UHI effect for study area.
Land-cover change and its time-series reconstructed using remotely sensed imageries in the Zhoushan islands
Jianyu Chen, Yuanzeng Zhan, Zhihua Mao
Coastal islands are located in transitional environments where land and sea interact. It is main frontier to develop oceanic economy and to utilize oceanic resources. Insular environment is isolated and its ecosystem is also vulnerable. The exploitation and development of islands make result on its land-cover and land-use transition and the trace of the landcover change indicates the impact on it conversely. Many changes have taken place in coastal area of East China within past four decades, especially in rapidly developing large islands. For monitoring environmental changes in such area, this paper, taking Zhoushan Island and its surrounding islands as an example, explored the temporal composition and spatial configuration of the land-cover trajectories. The recent land-cover data derived from both SPOT5 imageries and the last land-use data which came from investigation department. The historical distribution in 1980 was obtained from visual interpretation of CORONA photograph. Then the land-cover changed map could be derived through previous and last land-cover map. And the following time-series of land-cover was acquired from the supervised classification results of TM/ETM imageries which ranged from 1986 to 2000. The classification result was improved by limitation the sample selection in unchanged area in land-cover changed map in classification procedure. All these used satellite imageries were registered to the SPOT5 panchromatic imagery which was rectified using DGPS data in advance. Therefore, the temporal-spatial distributions of land-cover have been examined, reconstructed and analyzed with the support of GIS software. Based on those work, we revealed that the land-cover had changed rapidly in Zhoushan Island.
Spatiotemporal landscape pattern change of Hangzhou Xixi urban wetland growth in China
Daijian Tang, Qian Cheng, Qijia Lou
Based on the land use data interpreted from TM and ASTER images of Hangzhou Xixi Wetland in 1991, 2001 and 2005, in this paper, we first study the spatiotemporal diversity of urban growth and the evolution of urban landscape pattern in Hangzhou Xixi wetland during the rapid urbanization by calculating the indexes of landscape pattern such as Fractal Dimension, Peri-Area Ratio, Fragmentation, Shannon-diversity. The results showed that (1) the spatial landscapes from class level and landscape level have evident differences, (2) from class level, the changes of the main landscape in Southeast area were very complicate, and wetland and forest in Core area have the bigger Fractal Dimension and small Fragmentation, (3)from Landscape level, the Fragmentation and Shannon-diversity were bigger and the Dominance and Contagion have decreased, (4)the landscape in different times has different changes from wetland dynamic change,(5)during the process from the urban edge wetland to urban wetland, the landscape pattern change of Xixi urban wetland have evident differences because of the human influence.
The effects of chlorophyll-a and SST in the South China Sea area by typhoon near last decade
Based on satellite remote sensing to study the effects of ocean color and Sea Surface Temperature (SST) is the leading method at present. From 2000 to 2008, there were about 70 times storms or typhoons passed over the South China Sea Area (108-120°E, 14-24°N). In this article, authors used SeaWiFS, MODIS and serials of NOAA satellite data to statistic analysis the effects of chlorophyll-a (Chl-a) and SST in the study area caused by tropic storms and typhoons near last decade and found: firstly, the Ekman Pumping Velocity (EPV) was up-to 1.4x10-3 m s-1 by typhoon CHAUCHU in 2006, and was more ten times than that without typhoon. It pumped the nutrients to the euphotic zone and improved the increment of Chl-a concentration with the rate of 58.33%. and this typhoon caused the maximum decrease of SST was up to 7°C. At the same time, the average increment of Chl-a in the whole study area was about 21.13% but the decrease rate of SST was 6.36% by 16 typhoons. From the results of statistic analysis we found out that the isopycnal displacement of the seasonal thermocline explains 53% and the weight of the typhoon explains 55% of the variance of Chl-a by typhoons; In addition, the maximum amplitude of the increment of Chl-a in the study area was near to the east of Vietnam, it was up to 53%. But near the pear river estuary area with high Suspended Sand Concentration (SSC) the chl-a density decreased after typhoon and the descent rate of Chl-a was about 35%.
Mechanical monolithic tiltmeter for low frequency measurements
Fausto Acernese, Rosario De Rosa, Gerardo Giordano, et al.
The paper describes the application of a monolithic folded pendulum (FP) as a tiltmeter. Both the theoretical model and the experimental results of a tunable mechanical monolithic FP tiltmeter prototype are presented and discussed. Some of the most important characteristics, like the possibility of tuning its resonance frequency to values as low as 70mHz and its measured resolution of ≈ 0.1 nrad at 100mHz, are detailed. Among the first scientific results, earth tilt tides have been already observed with a monolithic FP tiltmeter prototype.
Analysis of land use change in the Manasi oasis of arid region, northwestern China using remote sensing and GIS
Xiaohong Gao, Ji Liang, Shixin Wu
The objective of the study was to quantify and analyze characteristics of LUCC in the spatial-temporal. Taking Manasi oasis in the north slope of Tianshan Mountains as the study area, we obtained the two date Landsat TM,ETM images of the late 1980s and the early 2000s. Radiometric correction was conducted using not less than 30 ground control points based on 1:500,000 topographical maps. A land use field investigation was carried out in order to have a general understanding to the area. Secondly, Land use maps were acquired by visual interpretation using EDRAS IMAGINE 8.7 and Arcinfo GIS 9.0. The conversion matrix of land use change was calculated to acquire the transition rates of land use change from the late 1980s to the early 2000s.The characteristics of LUCC in the spatial-temporal were studied and analyzed by adopting the land use dynamic degree model, conversion matrix model. Thirdly, landscape indices including landscape percentage (%land), mean patch size (MPS), patch density (PD), area-weighted mean patch fractal dimension (AWMPFD) were selected to quantify landscape pattern change of land use. The results indicated that during the 11 years, the areas of cultivated land, urban-built up, water land and marsh land increased, while those of grassland and forestland, saline and alkaline land and sand land decreased. The grassland was converted to cultivated land and urbanbuilt up. The landscape of the Manasi oasis has become more regularity, continuous and homogeneous. Favorable disturbance of human activity to landscape has made the oasis expansion process larger than the oasis desertification process.
Tropospheric profile of NO2 over the Po Valley measured with scan DOAS spectrometer
S. Masieri, D. Bortoli, A. Petritoli, et al.
A simple method to determine the vertical distribution of a pollutant gas, namely NO2, by means of the spectral measurements obtained with a scan-DOAS spectrometer, is presented. The developed technique can be summarized as follows: i) a series of quasi simultaneous measurements in the zenith and in others directions allowing for the determination of the Slant Column Density of NO2 for different elevation angles; ii) an active DOAS measurement for the determination of the NO2 concentration at the ground; iii) a set of Radiative Transfer Model (RTM) calculation of the scattering distance from the spectrometer, for a set of visibility values; iv) a recursive procedure of profile calculation starting from the first measurement and subtracting the value of NO2 Slant Column Density (SCD) retrieved from the measurement taken at the previous angle of sight. Measurements are carried out during summer 2007 in S. Pietro Capofiume (Bologna-Italy). The vertical distribution for NO2 obtained with the above described method has been compared with the profiles calculated with the GAMES (Gas Aerosol Modelling Evaluation System) model. The results of this comparison show some differences between the modelled and the measured profiles, probably due to box approximations in RTM calculation for measured profiles and to the large pixel grid (about 10x10 km2), for model evaluation.
Long term seismic noise acquisition and analysis in the Homestake mine with tunable monolithic sensors
Fausto Acernese, Rosario De Rosa, Riccardo De Salvo, et al.
In this paper we describe the scientific data recorded along one month of data taking of two mechanical monolithic horizontal sensor prototypes located in a blind-ended (side) tunnel 2000 ft deep in the Homestake (South Dakota, USA) mine chosen to host the Deep Underground Science and Engineering Laboratory (DUSEL). The two mechanical monolithic sensors, developed at the University of Salerno, are placed, in thermally insulating enclosures, onto concrete slabs connected to the bedrock, and behind a sound-proofing wall. The main goal of this experiment is to characterize the Homestake site in the frequency band 10-4 ÷ 30 H z and to estimate the level of Newtonian noise, providing also the necessary preliminary information to understand the feasibility of underground gravitational-wave interferometers sensitive at 1 H z and below.
Satellite and geophysical data for earthquake precursors assessment
Space-based observations, coupled with surface in-situ observations where available, can enable scientists to survey large surface areas for precursory signals, allowing the monitoring of broad areas of the surface of the earth where strong earthquakes can be expected to occur. The aim of this paper was to identify several types of earthquake precursors that might be observed from space. Satellite multispectral and hyperspectral imagery can look for specific gases and elements at the earth's surface, and it can also be used to detect surface temperature anomalies, geologic lineaments and analysis of active seismic faults. For seismic hazard analysis in Vrancea area, Romania have been selected the earthquake precursors detectable from space which can also be observed by ground-based monitoring experiments: surface deformation provided by GPS and SAR imaging, land surface temperature changes as possible precursors provided by ASTER, Landsat TM and ETM, electromagnetic and ionospheric anomalies, radon gas emissions in the faults areas prior to earthquakes, as well as seismicity. As Vrancea area has a significant regional tectonic activity in Romania and Europe, the joint analysis of geospatial and in-situ geophysical information is revealing new insights in the field of hazard assessment.
Calculation of light field in 3D cylinder cloud for greenhouse gases monitoring via GOSAT
In this work we suggest a precise calculation method for GOSAT program devoid of shortcomings of existing methods. The algorithm was tested on the plain unidirectional source which already has an exact solution to compare with. In that way the radiuses of mesh cylinders were a much larger than their height. Then we tested an algorithm on finite cylinders mesh and compared the results with Monte-Carlo simulation to be sure of its appropriateness. As a results of our work we got a fast and precise method for the calculation angular radiance with consideration of polarization.
Mining spectral libraries to study sensors' discrimination ability
Germain Forestier, Jordi Inglada, Cedric Wemmert, et al.
In remote sensing data classification, the ability to discriminate different land cover or material types is directly linked with the spectral resolution and sampling provided by the optical sensor. Several previous studies showed that the spectral resolution is a critical issue, especially to discriminate different land covers in urban areas. In spite of the increasing avaibility of hyperspectral data, multispectral optical sensors on board of several satellites are still acquiring everyday a massive amount of data with a relatively poor spectral resolution (i.e. usually about 4 to 7 spectral bands). These remotely sensed data are intensively used for Earth observation regardless of their limited spectral resolution. In this paper, we propose to study the capacity of discrimination of several of these optical sensors : Pleiades, QuickBird, SPOT5, Ikonos, Landsat, etc. To achieve this goal, we used different spectral libraries which provide spectra of materials and land covers generally with a fine spectral resolution (from 350 to 2400nm with 10nm bandwidth). These spectra were extracted from these libraries and convolved with the Relative Spectral Responses (RSR) of each sensor to create spectra at the sensors' resolutions. Then, these reduced spectra were evaluated thanks to classical separability indices and machine learning tools. This study focuses on the capacity of each sensor to discriminate different materials according to its spectral resolution.
Tunable mechanical monolithic horizontal accelerometer for low frequency seismic noise measurement
F. Acernese, R. De Rosa, G. Giordano, et al.
This paper describes a mechanical horizontal monolithic sensor for geophysical applications developed at the University of Salerno. The instrument is basically a monolithic tunable folded pendulum, shaped with precision machining and electric-discharge-machining, that can be used both as seismometer and, in a force-feedback configuration, as accelerometer. It is a very compact instrument, very sensitive in the low-frequency seismic noise band, with a very good immunity to environmental noises, whose main characteristics are the tunability of the resonance frequency and the integrated laser optical readout, consisting of an optical lever and an interferometer. The theoretical sensitivity curves are in a very good agreement with the measurements. A direct comparison of its performances with the STS-2 ones shows that better performances have been reached with the interferometric readout (≈ 10-12 m/√H z in the band 10-1 ÷ 10 H z as seismometer. Finally, the first results as accelerometer (force feed-back configuration) are also presented and discussed.
Digital and interactive learning modules: a way to integrate remote sensing methods in secondary education
Kerstin Voss, Roland Goetzke, Henryk Hodam
Remote sensing only plays a tangential role in schools, regardless of the political claims to strengthen the support for teaching on the subject. A lot of the computer software explicitly developed for school lessons has not yet been implemented due to its complexity. Thereby, the subject is either not at all integrated into the curriculum or does not pass the step of an interpretation of analogue images. In fact, the subject of remote sensing requires a consolidation of physics and mathematics as well as competences in the fields of media and methods apart from the mere visual interpretation of satellite images. In order to integrate remote sensing in a sustainable manner digital, interactive and interdisciplinary learning modules promoting media and method qualifications as well as independent working are provided.
Adaptation of building extraction rule sets derived from MFC3 and UltraCamD arial image data sets
In the context of rapid expansion of many cities to enormous agglomerations with high population density and a worldwide urbanization process serious impacts on environment in urban areas evolve. There is a high demand for the development and application of efficient methods to analyze and monitor changes in urban areas, to support the planning decisions in these regions and for security and risk assessment. Efficient, accurate and reliable extraction of buildings and roof surfaces and their inventory in geographic information systems plays a major role in this context. Previous analyses of digital airborne data sets show up that the inventory mapping and assessment of building changes is only possible on the basis of multi-temporal data sets and digital surface models with high resolution. These analyses confirm explicitly that both high heterogeneity and diversification of urban regions as well as the availability of data sets from different camera systems increase the need for automated and transferable extraction methods. In this context two data sets from different high resolution sensors are used for the development of transferable extraction rule sets within the object-based classification method in Definiens Developer. The Multifunctional Camera (MFC3) and the UltraCamD (UCD) data sets not only have diverse geometric but also different radiometric characteristics. As a study area the centre of Berlin, Germany was selected. Two approaches to generate comparable results from different data sources are tested. The first step deals with the generation of statistical parameters and the normalization of the two data sets. The second step addresses the development and adaptation of the rule set for a robust and universal segmentation and classification process.
The most effective statistical approach to correct environmental satellite data
The proposed paper apply novel statistical approach to correct radiometric data measured by Advanced Very High Resolution Radiometers(AVHRR) onboard the National Oceanic and Atmospheric Administration (NOAA) Polar Orbiting Environmental Satellites(POES). This paper investigates Normalized Difference Vegetation Index (NDVI) stability in the NOAA/NESDIS Global Vegetation Index (GVI) data during 1982-2003. AVHRR weekly data for the five NOAA afternoon satellites for the China dataset is studied, for it includes a wide variety of different ecosystems represented globally. It was found that data for the years 1988, 1992, 1993, 1994, 1995 and 2000 are not stable enough compared to other years because of satellite orbit drift, and AVHRR sensor degradation. It is assumed that data from NOAA-7 (1982, 1983), NOAA-9 (1985, 1986), NOAA-11 (1989, 1990), NOAA-14 (1996, 1997), and NOAA-16 (2001, 2002) to be standard because these satellites equator crossing time fall within 1330 and 1500, and hence maximizing the value of coefficients. The crux of the proposed correction procedure consists of dividing standard years data sets into two subsets. The subset 1 (standard data correction sets) is used for correcting unstable years and then corrected data for this years compared with the standard data in the subset 2 (standard data validation sets). In this paper, we apply empirical distribution function (EDF) to correct this deficiency of data for the affected years. It allows one to represent any global ecosystem from desert to tropical forest and to correct deviations in satellite data due to satellite technical problems. The corrected data set can be used for climatological research.