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München, Germany

Chuvieco E.,University of Alcala | Sandow C.,GAF AG | Guenther K.P.,German Aerospace Center | Gonzalez-Alonso F.,Research Center Forestal | And 6 more authors.
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2012

The European Space Agency (ESA) Climate Change Initiative (CCI) is part of the European contribution to the Global Climate Observing System (GCOS) program. Fire disturbance is one of the Essential Climate Variables (ECV) included in the ESA CCI program. It focus on mapping burned area (BA) using European sensors (ATSR, VEGETATION and MERIS data), and in comparing the performance of the results with other existing datasets. The project aims at developing and validating algorithms to produce consistent, stable, error-characterized global BA information. The project includes as well developing algorithms to generate georeferenced and calibrated reflectances of (A)ATSR, VEGETATION and MERIS data, identifying potential sources of confusion with burned areas (clouds, smoke, cloud shadows, water, snow, topographic shadows). The final product will be a merging of BA information derived from three different sensors . The outputs will be adapted to the needs of the atmospheric and vegetation modelling communities.

Grant K.,Institute for Crop Science and Plant Breeding | Siegmund R.,GAF AG | Wagner M.,GAF AG | Hartmann S.,Institute for Crop Science and Plant Breeding
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives | Year: 2015

Cutting date and frequency are important parameters determining grassland yields in addition to the effects of weather, soil conditions, plant composition and fertilisation. Because accurate and area-wide data of grassland yields are currently not available, cutting frequency can be used to estimate yields. In this project, a method to detect cutting dates via surface changes in radar images is developed. The combination of this method with a grassland yield model will result in more reliable and regional-wide numbers of grassland yields. For the test-phase of the monitoring project, a study area situated southeast of Munich, Germany, was chosen due to its high density of managed grassland. For determining grassland cutting robust amplitude change detection techniques are used evaluating radar amplitude or backscatter statistics before and after the cutting event. CosmoSkyMed and Sentinel-1A data were analysed. All detected cuts were verified according to in-situ measurements recorded in a GIS database. Although the SAR systems had various acquisition geometries, the amount of detected grassland cut was quite similar. Of 154 tested grassland plots, covering in total 436 ha, 116 and 111 cuts were detected using CosmoSkyMed and Sentinel-1A radar data, respectively. Further improvement of radar data processes as well as additional analyses with higher sample number and wider land surface coverage will follow for optimisation of the method and for validation and generalisation of the results of this feasibility study. The automation of this method will than allow for an area-wide and cost efficient cutting date detection service improving grassland yield models.

Siegmund R.,GAF AG | Ciappa A.,E Geos S.p.a. | Schaertel A.,GAF AG | Pietranera L.,E Geos S.p.a.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

SAR systems are recently used to generate robust and projectable information about maritime traffic, ice extent and geohazards. By utilising multiple SAR satellites dynamic information can be derived at variable temporal scales. Therefore acquisition systems and processing techniques become a key issue which is requested to work in a robust and efficient way. This paper will present generalized concepts for a monitoring approach that address unmatched or interferometric acquisitions. Its goal is to show the potential of increasing the acquisition rate but also to illustrate limitations resulting from the specific monitoring schemes and their combination. The paper will visualise practical examples derived from realized studies and projects. Finally we can conclude that an agile multi satellite and multi-mode SAR system, such as COSMO-SkyMed, is well suited to monitor to dynamic phenomena on the earth's surface. The practicability needs to be discussed in detail case by case related to the real world requirements. © 2014 SPIE.

Valeriano O.C.S.,University of Tokyo | Valeriano O.C.S.,Tokyo Institute of Technology | Valeriano O.C.S.,Egypt Japan University of Science and Technology | Koike T.,University of Tokyo | And 5 more authors.
Water Resources Research | Year: 2010

This study proposes a decision support system for real-time dam operation during heavy rainfall. It uses an operational mesoscale quantitative precipitation forecast (QPF) to force a hydrological model and considers the forecast error from the previous time step, which is introduced as a perturbation range applied to the most recent QPF. A weighting module accounts for the location, intensity, and extent of the error. Missing precipitation intensities within contributing areas and information from surrounding areas can both be considered. Forecast error is defined as the ratio of QPF to the observed precipitation within an evaluation zone (sub-basin, basin, buffer, or total domain). An objective function is established to minimize the flood volume at control points downstream and to maximize reservoir storage. The decision variables are the dam releases, which are constrained to the ensemble streamflow's information. A prototype was applied to one of the most important river basins in Japan, the Tone reservoir system. The efficiency of the approach was evident in reduced flood peaks downstream and increased water storage. The results from three events indicate that the developed decision support system is feasible for real-life dam operation. © 2010 by the American Geophysical Union.

Boger S.D.,University of Melbourne | Boger S.D.,GAF AG | Hirdes W.,Bundesanstalt fur Geowissenschaften und Rohstoffe | Ferreira C.A.M.,GaiaPix | And 3 more authors.
Gondwana Research | Year: 2015

U-Pb age data from southwest Madagascar provide a compelling case that the pre-Gondwana Indian plate was stitched with the arc terranes of the Arabian Nubian Shield along a suture that closed between 580 Ma and 520 Ma. The key observations supportive of this interpretation are: (1) metamorphism dated to 630-600 Ma is manifested only on the west side of the suture in rocks that have affinities with the oceanic and island arc terranes of the Arabian Nubian Shield, or which represent continental rocks welded to these terranes prior to the amalgamation of Gondwana, and (2) orogenesis at 580-520 Ma is manifest in rocks on both sides of the suture, an observation taken to mark the timing of collision and to reflect spatial continuity across the suture. In southwest Madagascar the distribution of metamorphic ages places the suture along the Beraketa high-strain zone, the tectonic boundary between the Androyen and Anosyen domains. Similar age relationships allow for the extrapolation of this tectonic boundary into both East Antarctica and Africa. © 2014.

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