Avaliação da Acurácia Vertical dos Modelos Digitais de Elevação SRTM, ALOS World 3D e ASTER GDEM: Um Estudo de Caso no Vale dos Vinhedos, RS – Brasil

Este estudo tem como objetivo avaliar a acurácia vertical dos Modelos Digitais de Elevação (MDEs) SRTM v.3, ALOS World 3D e ASTER GDEM v.2 na região da denominação de origem Vale dos Vinhedos, RS. Para tanto, os dados desses MDEs, com resolução espacial de 30 m, foram comparados com os de um MDE fotogramétrico com resolução espacial de 5 m no terreno, por meio de análises de regressão e correlação linear, e de perfis topográficos derivados desses modelos. O Padrão de Exatidão Cartográfica dos Produtos Cartográficos Digitais (PEC-PCD) de cada MDE foi analisado, para identificar a escala máxima de seu uso em estudos morfométricos, nas escalas 1:25.000, 1:50.000 e 1:100.000, por meio de cálculos da Tolerância Vertical e do Erro Médio Quadrático (EMQ). Os MDEs SRTM v.3 e ASTER GDEM v.2 atenderam o PEC-PCD altimétrico classe A na escala 1:100.000. Diferentemente do MDE ALOS World 3D que enquadrou-se na classe B para a escala de 1:100.000. Todos os modelos, na escala 1:50.000, enquadraram-se na classe D, enquanto que na escala 1:25.000 não houve enquadramento. O MDE SRTM v.3 foi o que apresentou melhores resultados morfométricos e o maior coeficiente de correlação de Pearson (r=0,995). Todos os MDEs avaliados neste estudo apresentaram morfologia próxima a do MDE fotogramétrico. Portanto, recomenda-se o uso de todos os MDEs analisados em estudos morfométricos da área de estudo, sendo necessário observar o objetivo do trabalho, bem como a escala de análise e a apresentação desses dados. Evaluation of the Vertical Acuracy of Digital Elevation Models SRTM, ALOS WORLD 3D and ASTER GDEM: a case study in Vale dos Vinhedos, RS - Brazil A B S T R A C TThis work aims to evaluate the vertical accuracy of the digital elevation models (DEMs) SRTM v.3, Alos World 3D and ASTER GDEM v.2 in Vale dos Vinhedos designation of origin (DO) region, RS. Thus, the DEM data with 30 m of the spatial resolution were compared with photogrammetric DEM data with 5 m of the spatial resolution by linear regression and correlation analyzes, and also, topographic profiles carried out with these models. The Cartographic Accuracy Standard (PEC) of each DEM was analyzed to identify the maximum scale for morphometric application, in scales 1:25.000, 1:50.000 and 1:100.000, by calculations of Vertical Tolerance and the Mean Square Error (MSE). All DEMs. All the models studied were classified in class A for the 1:100,000 scale, and for the 1:50,000 scale the analyzed models were classified in class C, while in 1:25.000 scale doesn´t have application. The DEM SRTM v.3 presented smaller altimetry errors compared to ASTER GDEM and Alos World 3D, as for mophometric analysis and Pearson correlation coefficient (r=0,995). It is worth mentioning that all models analyzed are statistically and morphologically close. Therefore, they can be used to conduct several studies, however it is necessary to have in mind the goal of the work, and the scale of analysis and presentation.Keywords: Vertical accuracy, SRTM v.3, Alos World 3D, ASTER GDEM

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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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Vertical accuracy assessment for SRTM and ASTER Digital Elevation Models: A case study of Najran city, Saudi Arabia

Ain Shams Engineering Journal ◽

10.1016/j.asej.2017.01.007 ◽

2018 ◽

Vol 9 (4) ◽

pp. 1807-1817 ◽

Cited By ~ 38

Author(s):

Ismail Elkhrachy

Keyword(s):

Saudi Arabia ◽

Accuracy Assessment ◽

Digital Elevation Models ◽

Digital Elevation ◽

Vertical Accuracy

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Dynamics of gully side erosion: a case study using tree roots exposure data

Open Geosciences ◽

10.1515/geo-2016-0013 ◽

2016 ◽

Vol 8 (1) ◽

Cited By ~ 5

Author(s):

Karel Šilhán ◽

Ivan Ružek ◽

Libor Burian

Keyword(s):

Detailed Analysis ◽

Erosion Rate ◽

Digital Elevation Models ◽

Natural Process ◽

Tree Roots ◽

Exposure Data ◽

Digital Elevation ◽

The Mean ◽

Reconstruction Period

AbstractErosion is a frequently studied natural process. Unfortunately, detailed analysis mostly requires longterm field monitoring or detailed digital elevation models (DEM) which are still absent for many areas. For these reasons we used the dendrogeomorphic method, a valuable tool for erosion analysis. The slopes of a ~220 m long gully close to the Kozárovce village (Slovakia) were the object of our study. We analyzed 53 tree root samples coming from 16 broad-leaved trees of different species. 23 erosion event years were explored during the reconstruction period AD 1972–2013. The mean erosion rate

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Comparison of Digital Elevation Models for the designing water reservoirs: a case study Pskom water reservoir

E3S Web of Conferences ◽

10.1051/e3sconf/202126403058 ◽

2021 ◽

Vol 264 ◽

pp. 03058

Author(s):

Khojiakbar Khasanov ◽

Azamat Ahmedov

Keyword(s):

Water Reservoir ◽

Vertical Axis ◽

Ground Control ◽

Control Points ◽

Alos Palsar ◽

Aster Gdem ◽

Ground Control Points ◽

Digital Elevation ◽

Vertical Accuracy

This study investigates the accuracy of various DEMs (SRTM DEM, ASTER GDEM, and ALOS PALSAR DEM) for the area of the designing Pskom water reservoir (recommended to construction in Pskom River, in Tashkent region. DEMs are compared for the study area using the Global Mapper application and selection Ground Control Points (GCP). The RMSE we calculate is the most easily interpreted statistic as the square root of the mean square error because it has the same units as the quantity drawn on the vertical axis. Results show that SRTM based measurements of ground control points (GCPs) exhibit RMSE of 15.72 m while ASTER DEM based measurements exhibits and RMSE of 18.47 m, ALOS PALSAR exhibit RMSE of 14.02 m for the Water reservoir located in the plain. There are AOS PALSAR outperforms SRTM and ASTER DEM in detecting vertical accuracy. Based on the capabilities of the Global Mapper program, we can build the longitudinal profile of the approximate location where the dam can be built in each DEM and compare. The results obtained show that the dam height is 187 m at ALOS PALSAR DEM, 168 m at ASTER GDEM, and 175 m at SRTM. The study found that using ALOS PALSAR data in the design of the proposed Pskom Reservoir for construction leads to a more accurate result. Comparing the DEMs data shows that there is more difference between the vertical accuracy; the horizontal accuracy level is almost the same. The results were obtained using ALOS PALSAR data in determining the storage volume (W=479368568 m3) and area (F=8.31 sq., km) of the water reservoir.

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Validation of Global Digital Elevation Models in Lagos State, Nigeria

Nigerian Journal of Environmental Sciences and Technology - March 2018 ◽

10.36263/nijest.2018.01.0058 ◽

2018 ◽

Vol 2 (1) ◽

pp. 78-88

Author(s):

I. D. Arungwa ◽

E. O. Obarafo ◽

C. J. Okolie

Keyword(s):

Root Mean Square Error ◽

Mean Square Error ◽

Root Mean Square ◽

Thermal Emission ◽

Survey Methods ◽

Digital Elevation Models ◽

Shuttle Radar Topography Mission ◽

Mean Square ◽

Digital Elevation ◽

Vertical Accuracy

Satellite-derived Digital Elevation Models (DEM) are fast replacing the classical method of elevation data acquisition by ground survey methods. The availability of free and easily accessible DEMs is no doubt of great significance and importance, and a valuable resource in the quest to accurately model the earth's surface topography. However, the suitability of Digital Elevation Models in simulating the topography of the earth at micro, local and regional scales is still an active area of research. The accuracy of Digital Elevation Models vary from one location to another. As such, it is important to conduct local and regional assessments to inform the global user community on the relative performance of these DEMs. This study evaluates the accuracy of the 30-metre Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Models version 2, the 1-kilometre GTOPO30, the 90-metre Shuttle Radar Topography Mission v4 and the 1-kilometre Shuttle Radar Topography Missionv2.1 Digital Elevation Models by validating with highly accurate GPS check-points over Lagos, Nigeria. With a Root Mean Square Error of 3.75m, the results show that Shuttle Radar Topography Mission v4 has the highest vertical accuracy followed by Shuttle Radar Topography Mission v2.1 (Root Mean Square Error: 5.73m), Advanced Spaceborne Thermal Emission and Reflection Radiometer (Root Mean Square Error: 21.70m), and GTOPO30 which shows the lowest vertical accuracy (Root Mean Square Error: 29.41m). By conducting the accuracy assessment of these products in Lagos, this study informs efforts directed at the exploitation of these Digital Elevation Models for topographic mapping and other scientific and environmental application.

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