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  • SWACI is a research project of DLR supported by the State Government of Mecklenburg-Vorpommern. Radio signals, transmitted by modern communication and navigation systems may be heavily disturbed by space weather hazards. Thus, severe temporal and spatial changes of the electron density in the ionosphere may significantly degrade the signal quality of various radio systems which even may lead to a complete loss of the signal. By providing specific space weather information, in particular now- and forecast of the ionospheric state, the accuracy and reliability of impacted communication and navigation systems shall be improved. NmF2 Maps and 3D electron density distribution: According to the pioneer work of Sir E. Appleton the vertical structure of the terrestrial ionosphere may be devided into different layers (D, E, F1, F2) with different physical characteristics. The layers are primarily characterized by its height and peak electron density. Typical plasma frequencies /electron densities are in the order of 10 MHz /1012 electrons / m3. Shown are here global maps of the peak electron density of the F2 layer and related electron density maps at selected altitudes. The figures provide a first estimation of the three dimensional electron density distributions around the globe. For more details see http://swaciweb.dlr.de/data-and-products/public/nmf2/?L=1.

  • SWACI is a research project of DLR supported by the State Government of Mecklenburg-Vorpommern. Radio signals, transmitted by modern communication and navigation systems may be heavily disturbed by space weather hazards. Thus, severe temporal and spatial changes of the electron density in the ionosphere may significantly degrade the signal quality of various radio systems which even may lead to a complete loss of the signal. By providing specific space weather information, in particular now- and forecast of the ionospheric state, the accuracy and reliability of impacted communication and navigation systems shall be improved. The total electron content (TEC) is defined as the integral of the electron density along the ray path between satellite and receiver. Thus, TEC provides the number of electrons per square meter. The most frequently used unit is 1TECU = 1x1016 electrons / m2. TEC is derived from dual frequency code and carrier phase measurements provided by Global Navigation Satellite Systems (GNSS). SWACI uses GPS measurements from various European GNSS networks such as the International GNSS Service (IGS), European Reference Frame (EUREF), Norwegian Mapping Authority (NMA), and ascos distributed by the Federal Agency of Cartography and Geodesy (BKG) Frankfurt. The global TEC maps are mainly created by using data provided by the International GNSS Service Real-Time Pilot Project (IGS-RTPP). To generate TEC maps of vertical TEC, the slant measurements have to be transformed to the vertical. In a first approximation the ionospheric range error in GNSS is proportional to TEC. These TEC maps are used to derive latitudinal and zonal gradients, rate of change of TEC (5 min increments), 27 days medians, hourly forecasts of TEC, and corresponding error estimates. Spatial resolution (latitude x longitude): 2 °x 2° (Europe), 2.5° x 5° (globally)

  • The TanDEM-X Forest/Non-Forest Map is a project developed by the Microwaves and Radar Institute at the German Aerospace Center (DLR), within the activities of the TanDEM-X mission. The goal is the derivation of a global forest/non-forest classification mosaic from TanDEM-X bistatic interferometric synthetic aperture radar (InSAR) data, acquired for the generation of the global digital elevation model (DEM) in Stripmap single polarization (HH) mode. The TanDEM-X Forest/Non-Forest Map (FNF) has been generated by processing and mosaicking more than 500,000 TanDEM-X bistatic images acquired from 2011 until 2015. The map has a spatial resolution of 50 x 50m. Forested and non-forested areas are depicted in green and white, respectively. Water bodies are depicted in blue and black is used for identifying urban areas and invalid pixels. For more information, please visit: https://www.dlr.de/hr/en/desktopdefault.aspx/tabid-12538/21873_read-50027/

  • The Medium Resolution Imaging Spectrometer (MERIS) on Board ESA’s ENVISAT provides spectral high resolution image data in the visible-near infrared spectral region (412-900 nm) at a spatial resolution of 300 m. For more details on ENVISAT and MERIS see http://envisat.esa.int/ Spectral high resolution measurements allow to assess different water constituents in optically complex case-2 waters (IOCCG, 2000). The main groups of constituents are Chlorophyll, corresponding to living phytoplankton, suspended minerals or sediments and dissolved organic matter. They are characterised by their specific inherent optical properties, in particular scattering and absorption spectra. The Baltic Sea Water Constituents product was developed in a co-operative effort of DLR (Remote Sensing Technology Institute IMF, German Remote Sensing Data Centre DFD), Brockmann Consult (BC) and Baltic Sea Research Institute (IOW) in the frame of the MAPP project (MERIS Application and Regional Products Projects). The data are processed on a regular (daily) basis using ESA standard Level-1 and -2 data as input and producing regional specific value added Level-3 products. The regular data reception is realised at DFD ground station in Neustrelitz. For more details the reader is referred to http://eoweb.dlr.de/short_guide/Waterparameter_BalticSea.html and http://www.brockmann-consult.de/mapp/project_information.htm This product provides monthly maps.

  • The RapidEye Earth observation system comprises five satellites equipped with high-resolution optical sensors. Co-funded by the German Federal Government, the fleet of satellites was launched from the Baikonur cosmodrome in Kazakhstan in 2008. RapidEye is now being owned by Planet Labs, Inc. The RapidEye constellation is capable of taking images of the Earth's surface at high repeat rates. Each point on Earth can be imaged at least once per day. With a spatial resolution of 6.5 m the 5-band sensors onboard the RapidEye satellites operate in the visible and near-infrared portions of the electromagnetic spectrum. For more information see http://www.dlr.de/rd/en/desktopdefault.aspx/tabid-2440/3586_read-5336/ or https://www.planet.com/products/planet-imagery/ The RapidEye Science Archive (RESA), which allows Germany-based researchers to apply for free RapidEye imagery, is now being operated by Planet Labs Germany GmbH. For more information see https://resa.planet.com/

  • The Al Zaatari refugee camp in Jordan is situated approx. 12 km from the Syrian border and in close proximity to the city of Al Mafraq (10 km). Due to heavy rainfall in the region parts of the Zaatari camp are affected by flooding. The map shows the flood situation derived by semi-automatic image analysis of TerraSAR-X data acquired on January 10, 2013 at 03:38:49 UTC. Furthermore basic reference information, digitized on the basis of WorldView-2 satellite data acquired on January 03, 2013, at 08:52:52 UTC, is depicted. The contour lines were derived from ASTER GDEM 2 data (vertical accuracy +/- 6m). For a more detailed view on the flood situation, parts of the camp area are also shown in the zoom boxes. The results of the image interpretation and analysis have not been validated in the field. WorldView-2 satellite data acquired on January 03, 2013, is used as backdrop. Please note that flood waters in settlement areas might not be fully captured and the water extent might be underestimated due to sensor characteristics. Thus especially shallow water bodies might not be fully captured. The products elaborated for this Rapid Mapping Activity are realised to the best of our ability, within a very short time frame, optimising the material available. All geographic information has limitations due to the scale, resolution, date and interpretation of the original source materials. No liability concerning the content or the use thereof is assumed by the producer. The ZKI crisis maps are constantly updated. Please make sure to visit http://www.zki.dlr.de for the latest version of this product.

  • The RapidEye Earth observation system comprises five satellites equipped with high-resolution optical sensors. Co-funded by the German Federal Government, the fleet of satellites was launched from the Baikonur cosmodrome in Kazakhstan in 2008. RapidEye is now being owned by Planet Labs, Inc. The RapidEye constellation is capable of taking images of the Earth's surface at high repeat rates. Each point on Earth can be imaged at least once per day. With a spatial resolution of 6.5 m the 5-band sensors onboard the RapidEye satellites operate in the visible and near-infrared portions of the electromagnetic spectrum. For more information see http://www.dlr.de/rd/en/desktopdefault.aspx/tabid-2440/3586_read-5336/ or https://www.planet.com/products/planet-imagery/ The RapidEye Science Archive (RESA), which allows Germany-based researchers to apply for free RapidEye imagery, is now being operated by Planet Labs Germany GmbH. For more information see https://resa.planet.com/

  • This product shows Snow Cover Duration Early Season (SCDES). SCDES represents the SCD between September 1st and January 15th of a given hydrological year. Information about extent, beginning, duration and melt of snow cover are important for climate research, hydrological applications, flood prediction and weather forecast. Climate change is influencing the characteristics and duration of snow cover, affecting landscape, hydrology, flora, fauna, and humans in equal measure. Therefore, precise information about the different snow parameters and their development over time are particularly important for various research fields. The “Global SnowPack” is a dataset containing information about snow cover parameters on a global scale. Overall, early season, and late season snow cover duration are included and allow detailed insights in the characteristics of this most relevant part of Earth’s cryosphere. The parameters are being derived from daily, operational MODIS snow cover products for every year since 2000. The negative effects of polar darkness and cloud coverage are compensated by applying several processing steps. Thereby, a unique global dataset can be provided that is characterized by its high accuracy, a spatial resolution of 500 meter and continuous future enhancements. For more information please also refer to: Dietz, A. J., C. Kuenzer, and S. Dech. 2015: Global SnowPack – “A new set of snow cover parameters to study status and dynamics of the planetary snow cover extent.“ accepted for publication in Remote Sensing Letters. Dietz, A. J., C. Conrad, C. Kuenzer, G. Gesell, and S. Dech. 2014. “Identifying Changing Snow Cover Characteristics in Central Asia between 1986 and 2014 from Remote Sensing Data.” Remote Sensing 6 (12): 12752–75. doi:10.3390/rs61212752. Dietz, A. J., C. Kuenzer, and C. Conrad. 2013. “Snow-Cover Variability in Central Asia between 2000 and 2011 Derived from Improved MODIS Daily Snow-Cover Products.” International Journal of Remote Sensing 34 (11): 3879–3902. Dietz, A. J., C. Wohner, and C. Kuenzer. 2012. “European Snow Cover Characteristics between 2000 and 2011 Derived from Improved MODIS Daily Snow Cover Products.” Remote Sensing 4 (8): 2432–54. doi:10.3390/rs4082432.

  • The objective of the pan-European project CORINE Land Cover (CLC) is the provision of a unique and comparable data set of land cover for Europe and the delivery of regular updates to register also the land cover and land use changes over time. It is part of the European Union programme CORINE (Coordination of Information on the Environment). The mapping of the land cover and land use was performed on the basis of satellite remote sensing images. The first CLC data base CLC1990, which was finalized in the 1990s, consistently provided land use information comprising 44 classes, out of which 37 classes are relevant in Germany. The first two updates for Europe were based on the reference years 2000 and 2006. For Germany, DLR-DFD was responsible for the creation of CLC2000 and CLC2006 on behalf of the Federal Environment Agency. In addition to the updated land cover, change datasets were also parts of the project. For deriving a meaningful CLC2000 change product, it became necessary to re-interprete parts of the satellite data of 1990 and to create a revised product, called CLC1990 (rev). Further details: http://www.dlr.de/eoc/en/desktopdefault.aspx/tabid-11882/20871_read-48836/

  • This collection contains radar image products of the German national TerraSAR-X mission acquired in Spotlight mode. Spotlight imaging allows for a spatial resolution of up to 2 m at a scene size of 10 km (across swath) x 10 km (in orbit direction). TerraSAR-X is a sun-synchronous polar-orbiting, all-weather, day-and-night X-band radar earth observation mission realized in the frame of a public-private partnership between the German Aerospace Center (DLR) and Airbus Defence and Space. For more information concerning the TerraSAR-X mission, the reader is referred to: http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10377/565_read-436/

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