Flash flood has been increasing in the Khartoum area, Sudan due to geographical conditions and climatic change as heavy rainfall and high temperature, therefore the present work tried to estimate the sensitivity of flash flood. The present work proposes an advanced technique of flood sensitivity mapping using the method of analytical hierarchy process. Ten factors as elevation, slope, distance ...

Accurate digital terrain models (DTMs) are necessary for a wide variety applications. National-scale mediumresolution elevation data have been acquired for the conterminous United States under the USGS National Elevation Data (NED; 10 m and 30 m), the Shuttle Radar Topographic Mapping (SRTM; 30 m), and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER; 30 m) programs. In...

Remote sensing and GIS approaches have provided valuable information on modeling water resources, particularly in arid regions. The Sahara of North Africa, which is one the driest regions Earth, experienced several pluvial conditions past that could stored significant amounts groundwater. Thus, harvesting by revealing groundwater prospective zones (GWPZs) highly important to security management...

This paper presents a methodology for planimetric adjustment of elevation data to the SRTM Digital Elevation Model (SRTMDEM), by correlation. It can be applied to geo-reference any geographic dataset with an elevation component, such as rasterised maps with contours or DEMs. The accuracy around 5 meters was achieved by this geo-referencing method assessed using elevation data from Portugal deri...

Interferometric ALOS PALSAR Fine Beam Single/Dual, multi-temporal ENVISAT ASAR Alternating Polarization, and Landsat-5 TM/-7 ETM+ data are used for the generation of land cover and change maps. In synthesis, the product generation foresees two main steps: The first one consists in a rigorous data pre-processing, including interferometric processing (PALSAR), geometric / radiometric calibration ...

DISCLAIMER This document describes work undertaken as part of a programme of study at the Faculty of Geo-Information Science and Earth Observation of the University of Twente. All views and opinions expressed therein remain the sole responsibility of the author, and do not necessarily represent those of the Faculty. i ABSTRACT 2.5D building modelling is of great interest for visualization, simu...

Fractional tree cover (Fcover) is an important biophysical variable for measuring forest degradation and characterizing land cover. Recently, atmospherically corrected Landsat data have become available, providing opportunities for high-resolution mapping of forest attributes at global-scale. However, topographic correction is a pre-processing step that remains to be addressed. While several me...

TanDEM-X is a challenging radar mission. It consists of a synthetic aperture radar interferometer with two almost identical satellites flying in a closely controlled formation. With a typical separation between the satellites of 120 to 500 m a global Digital Elevation Model (DEM) with 2 m relative height accuracy at 12 m posting is being generated. While the main mission phase for DEM data acqu...

Most environmental modelling takes place within the toposequence. Conventionally, the terrain variables for these purposes have been derived from digital elevation models (DEMs) produced from large scale topographic maps (e.g. 1:25,000 (approx 30 meters)) or topographic data at that scale. Coverage in Australia of this scale DEM is very limited. However, global and continental coverage of DEMs ...

1 The Digital Elevation Model that has been derived from the February 2000 2 Shuttle Radar Topography Mission (SRTM) has been one of the most 3 important publicly available new spatial datasets in recent years. However, the 4 'finished' grade version of the data (also referred to as Version 2) still contains 5 data voids (some 836,000 km 2) – and other anomalies – that prevent immediate 6 use i...