ALTIMETRY ASSESSMENT OF ASTER GDEM v2 AND SRTM v3 DIGITAL ELEVATION MODELS: A CASE STUDY IN URBAN AREA OF BELO HORIZONTE, MG, BRAZIL

Abstract: This work is an altimetry evaluation study involving Digital Elevation Models ASTER GDEM version 2 and SRTM version 3. Both models are readily available free of charge, however as they are built from different remote sensing methods it is also expected that they present different data qualities. LIDAR data with 25 cm vertical accuracy were used as reference for assessment validation. The evaluation study, carried out in urbanized area, investigated the distribution of the residuals and the relationship between the observed errors with land slope classes. Remote sensing principles, quantitative statistical methods and the Cartographic Accuracy Standard of Digital Mapping Products (PEC-PCD) were considered. The results indicated strong positive linear correlation and the existence of a functional relationship between the evaluated models and the reference model. Residuals between -4.36 m and 3.11 m grouped 47.7% of samples corresponding to ASTER GDEM and 63.7% of samples corresponding to SRTM. In both evaluated models, Root Mean Square Error values increased with increasing of land slope. Considering 1: 50,000 mapping scale the PEC-PCD classification indicated class B standard for SRTM and class C for ASTER GDEM. In all analyzes, SRTM presented smaller altimetry errors compared to ASTER GDEM, except in areas with steep relief.

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Investigating the Impact of Digital Elevation Models on Sentinel-1 Backscatter and Coherence Observations

Remote Sensing ◽

10.3390/rs12183016 ◽

2020 ◽

Vol 12 (18) ◽

pp. 3016

Author(s):

Ignacio Borlaf-Mena ◽

Maurizio Santoro ◽

Ludovic Villard ◽

Ovidiu Badea ◽

Mihai Andrei Tanase

Keyword(s):

Remote Sensing ◽

Laser Scanning ◽

Digital Elevation Models ◽

Shuttle Radar Topography Mission ◽

Synthetic Aperture ◽

Mountainous Regions ◽

Aerial Laser Scanning ◽

Digital Elevation ◽

The Difference ◽

The Impact

Spaceborne remote sensing can track ecosystems changes thanks to continuous and systematic coverage at short revisit intervals. Active remote sensing from synthetic aperture radar (SAR) sensors allows day and night imaging as they are not affected by cloud cover and solar illumination and can capture unique information about its targets. However, SAR observations are affected by the coupled effect of viewing geometry and terrain topography. The study aims to assess the impact of global digital elevation models (DEMs) on the normalization of Sentinel-1 backscattered intensity and interferometric coherence. For each DEM, we analyzed the difference between orbit tracks, the difference with results obtained with a high-resolution local DEM, and the impact on land cover classification. Tests were carried out at two sites located in mountainous regions in Romania and Spain using the SRTM (Shuttle Radar Topography Mission, 30 m), AW3D (ALOS (Advanced Land Observation Satellite) World 3D, 30 m), TanDEM-X (12.5, 30, 90 m), and Spain national ALS (aerial laser scanning) based DEM (5 m resolution). The TanDEM-X DEM was the global DEM most suitable for topographic normalization, since it provided the smallest differences between orbital tracks, up to 3.5 dB smaller than with other DEMs for peak landform, and 1.4–1.9 dB for pit and valley landforms.

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A robust interpolation method for constructing digital elevation models from remote sensing data

Geomorphology ◽

10.1016/j.geomorph.2016.06.025 ◽

2016 ◽

Vol 268 ◽

pp. 275-287 ◽

Cited By ~ 21

Author(s):

Chuanfa Chen ◽

Fengying Liu ◽

Yanyan Li ◽

Changqing Yan ◽

Guolin Liu

Keyword(s):

Remote Sensing ◽

Interpolation Method ◽

Digital Elevation Models ◽

Remote Sensing Data ◽

Sensing Data ◽

Digital Elevation

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Area Partitioning for Channel Network Extraction Using Digital Elevation Models and Remote Sensing

IEEE Geoscience and Remote Sensing Letters ◽

10.1109/lgrs.2011.2163812 ◽

2012 ◽

Vol 9 (2) ◽

pp. 194-198 ◽

Cited By ~ 8

Author(s):

Dayong Shen ◽

Yongwei Sheng

Keyword(s):

Remote Sensing ◽

Digital Elevation Models ◽

Channel Network ◽

Digital Elevation

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Detecting Mountain Peaks and Delineating Their Shapes Using Digital Elevation Models, Remote Sensing and Geographic Information Systems Using Autometric Methodological Procedures

Remote Sensing ◽

10.3390/rs4030784 ◽

2012 ◽

Vol 4 (3) ◽

pp. 784-809 ◽

Cited By ~ 24

Author(s):

Tomaž Podobnikar

Keyword(s):

Remote Sensing ◽

Information Systems ◽

Geographic Information Systems ◽

Digital Elevation Models ◽

Geographic Information ◽

Digital Elevation ◽

Methodological Procedures

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EVALUATION DIGITAL ELEVATION MODEL GENERATED BY SYNTHETIC APERTURE RADAR DATA

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xli-b1-57-2016 ◽

2016 ◽

Vol XLI-B1 ◽

pp. 57-62

Author(s):

H. B. Makineci ◽

H. Karabörk

Keyword(s):

Remote Sensing ◽

Digital Elevation Model ◽

Interpolation Method ◽

Digital Elevation Models ◽

European Space Agency ◽

Mountain Area ◽

Synthetic Aperture Radar Data ◽

Radar Images ◽

Digital Elevation ◽

Elevation Model

Digital elevation model, showing the physical and topographical situation of the earth, is defined a tree-dimensional digital model obtained from the elevation of the surface by using of selected an appropriate interpolation method. DEMs are used in many areas such as management of natural resources, engineering and infrastructure projects, disaster and risk analysis, archaeology, security, aviation, forestry, energy, topographic mapping, landslide and flood analysis, Geographic Information Systems (GIS). Digital elevation models, which are the fundamental components of cartography, is calculated by many methods. Digital elevation models can be obtained terrestrial methods or data obtained by digitization of maps by processing the digital platform in general. Today, Digital elevation model data is generated by the processing of stereo optical satellite images, radar images (radargrammetry, interferometry) and lidar data using remote sensing and photogrammetric techniques with the help of improving technology. One of the fundamental components of remote sensing radar technology is very advanced nowadays. In response to this progress it began to be used more frequently in various fields. Determining the shape of topography and creating digital elevation model comes the beginning topics of these areas. It is aimed in this work , the differences of evaluation of quality between Sentinel-1A SAR image ,which is sent by European Space Agency ESA and Interferometry Wide Swath imaging mode and C band type , and DTED-2 (Digital Terrain Elevation Data) and application between them. The application includes RMS static method for detecting precision of data. Results show us to variance of points make a high decrease from mountain area to plane area.

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Assessment of open source digital elevation models (SRTM-30, ASTER, ALOS) for erosion processes modeling

Journal of Geology Geography and Geoecology ◽

10.15421/111911 ◽

2019 ◽

Vol 28 (1) ◽

pp. 95-105 ◽

Cited By ~ 1

Author(s):

I. P. Kovalchuk ◽

K. A. Lukianchuk ◽

V. A. Bogdanets

Keyword(s):

Open Source ◽

Correlation Coefficient ◽

Root Mean Square ◽

Digital Elevation Models ◽

Mean Square ◽

Erosion Processes ◽

Aster Gdem ◽

Digital Elevation ◽

Vertical Accuracy ◽

Mean Square Errors

The relief has a major impact on the landscape`s hydrological, geomorphological and biological processes. Many geographic information systems used elevation data as the primary data for analysis, modeling, etc. A digital elevation model (DEM) is a modern representation of the continuous variations of relief over space in digital form. Digital Elevation Models (DEMs) are important source for prediction of soil erosion parameters. The potential of global open source DEMs (SRTM, ASTER, ALOS) and their suitability for using in modeling of erosion processes are assessed in this study. Shumsky district of Ternopil region, which is located in the Western part of Ukraine, is the area of our study. The soils of Shumsky district are adverselyaffected by erosion processes. The analysis was performed on the basis of the characteristics of the hydrological network and relief. The reference DEM was generated from the hypsographic data(contours) on the 1:50000 topographical map series compiled by production units of the Main Department of Geodesy and Cartography under the Council of Ministers. The differences between the reference DEM and open source DEMs (SRTM, ASTER and ALOS) are examined. Methods of visual detection of DEM defects, profiling, correlation, and statistics were used in the comparative analysis. This research included the analysis oferrors that occurred during the generation of DEM. The vertical accuracy of these DEMs, root mean square error (RMSE), absolute and relative errors, maximum deviation, and correlation coefficient have been calculated. Vertical accuracy of DEMs has been assessed using actual heights of the sample points. The analysis shows that SRTM and ALOS DEMs are more reliable and accurate than ASTER GDEM. The results indicate that vertical accuracy of DEMs is 7,02m, 7,12 m, 7,60 mand 8,71 m for ALOS, SRTM 30, SRTM 90 and ASTER DEMs respectively. ASTER GDEM had the highest absolute, relative and root mean square errors, the highest maximum positive and negative deviation, a large difference with reference heights, and the lowest correlation coefficient. Therefore, ASTER GDEM is the least acceptable for studying the intensity and development of erosion processes. The use of global open source DEMs, compared with the vectorization of topographic maps,greatly simplifies and accelerates the modeling of erosion processes and the assessment of the erosion risk in the administrative district.

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Utilização de cinco bases cartográficas distintas para a determinação de áreas de preservação permanente no município de Rio Acima, MG: divergências en-tre os resultados / Using five different cartographic bases for determining permanent preservation area

Caderno de Geografia ◽

10.5752/p.2318-2962.2016v26nesp1p136 ◽

2016 ◽

Vol 26 (1) ◽

pp. 136

Author(s):

Felipe Silva Guimarães ◽

Lucas Da Silva Guimarães

Keyword(s):

Digital Elevation Models ◽

Minas Gerais ◽

Metropolitan Region ◽

Second Stage ◽

Digital Elevation ◽

Minas Gerais State ◽

Vector Base ◽

The Law ◽

Belo Horizonte ◽

The City

O estudo foi realizado no município de Rio Acima, localizado ao sul da região metropolitana de Belo Horizonte - MG. Na primeira etapa, foi feita a determinação das áreas de preservação permanente (APPs) do município, segundo a Lei 12.651 e a resolução CONAMA 303/2002 (esta última para delimitar as APPs de topo de morro), utilizando cinco bases topográficas distintas: vetorização de cartas do IBGE na escala de 1:50.000, imagem SRTM, Topodata, ASTER V2 e uma base vetorial disponibilizada pelo Codemig com curvas de nível equidistantes em 10 metros. Na segunda etapa, foram calculadas as áreas de cada uma das classes de APP resultantes dos mapeamentos feitos a partir de todas as bases e, em seguida, estes valores foram comparados. Ao final, foi observado que os resultados obtidos a partir da base do IBGE e da imagem ASTER V2 são os que apresentam característica mais restritiva, ou seja, com maiores áreas de preservação. Por outro lado, o mapa de áreas de preservação permanente confeccionado a partir da imagem SRTM foi o que apresentou caráter menos restritivo. Neste estudo também são discutidas outras diferenças entre os mapas elaborados a partir das cinco bases. Palavras–chave: Município de Rio Acima, áreas de preservação permanente, modelos digitais de elevação, resolução espacial. Abstract This study was conducted in the municipality of Rio Acima (Minas Gerais State) located in the southern Belo Horizonte metropolitan region. In the first stage five different topographic bases were used to lay down the city permanent preservation areas (PPA) according to the Law 12,651 and CONAMA resolution 303/2002 (the latter to delimit the hilltop’s PPAs PPAs). These bases are the following: the vector at a 1:50.000 scale provided by the Brazilian Institute of Geography and Statistics (IBGE), SRTM image, image provided by INPE Topodata project, ASTER V2 Image and a vector base released by Codemig with 10 meters contour distance. In the second stage the areas of each one PPA classes were calculated resulting from all mapping bases. Then these values were compared. Finally it was observed that the results obtained from the ASTER V2 image and IBGE base are those with more restrictive features or in other words the result with lager PPAs. Moreover, the map of permanent preservation areas made from SRTM image showed the least restrictive character. This study also discusses other differences between the maps drawn from the five bases. Keywords: Rio Acima municipality, permanent preservation areas, digital elevation models, spacial resolution.

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