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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. 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)

  • 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)

  • DBFSAR, "Digital Beam Forming SAR", is an airborne very-high-resolution imaging radar (Synthetic Aperture Radar) sensor presently operated by the German Aerospace Center (DLR), Microwaves and Radar Institute (HR) since November 29, 2016. It is operated on a Dornier Do-228 aircraft from altitudes of 2000 to 6000 m above ground in X-band (3 cm wavelength) only, featuring four transmit (operated sequentially) and twelve parallel receive channels. Depending on antenna deployment, it is either fully polarimetric (HH,HV,VV,VH), inetrferomtric in along- and/or across-track mode, or can be operated as a digital beamforming SAR. It has full repeat-pass capabilities. Data are processed up to three different levels: RGI (Radar Geometry Image product), INF (Interferometric product) and GTC (Geocoded and Terrain-Corrected product). The data acquisition modes are selected based on the individually planned experiments. Achieved resolutions are presently 10 cm in azimuth and 17 cm in range but will go down significantly below 10 cm in both directions.

  • Indian Remote Sensing satellites (IRS) are a series of Earth Observation satellites, built, launched and maintained by Indian Space Research Organisation. The IRS series provides many remote sensing services to India and international ground stations. With 5 m resolution and products covering areas up to 70 km x 70 km IRS LISS-IV mono data provide a cost effective solution for mapping tasks up to 1:25'000 scale.

  • This collection contains monthly mean surface NO2 concentrations for Germany derived from Sentinel-5P/TROPOMI data. The Sentinel-5P NO2 data is generated by DLR and provided in the framework of the mFUND-Project "S-VELD". The surface NO2 data are concentrations with the unit "μg/m3". Sentinel-5P observes Germany once per day at ~12:00 UTC and only cloud-free measurements (cloud fraction less than ~0.2) are used. The Sentinel-5P surface NO2 data within each month are averaged and gridded onto a regular UTM grid. The number of measurements used in the calculation of the averaged value are included in this collection as well.

  • The dataset is based on an analysis combining Sentinel-1 (SAR), -2 (Multispectral) and GEDI (Global Ecosystem Dynamics Investigation, LiDAR) data to model vegetation structure information. The derived products show high-spatial resolution maps (10 m) of total canopy cover (cover density in %), Foliage height diversity (Fhd) index in meter, Plant area index (Pai) in meter and canopy height (rh95) in meter.

  • The Global Ozone Monitoring Experiment-2 (GOME-2) instrument continues the long-term monitoring of atmospheric trace gas constituents started with GOME / ERS-2 and SCIAMACHY / Envisat. Currently, there are three GOME-2 instruments operating on board EUMETSAT's Meteorological Operational satellites MetOp-A, -B and -C, launched in October 2006, September 2012, and November 2018, respectively. GOME-2 can measure a range of atmospheric trace constituents, with the emphasis on global ozone distributions. Furthermore, cloud properties and intensities of ultraviolet radiation are retrieved. These data are crucial for monitoring the atmospheric composition and the detection of pollutants. DLR generates operational GOME-2 / MetOp level 2 products in the framework of EUMETSAT's Satellite Application Facility on Atmospheric Chemistry Monitoring (AC-SAF). GOME-2 near-real-time products are available already two hours after sensing. OCRA (Optical Cloud Recognition Algorithm) and ROCINN (Retrieval of Cloud Information using Neural Networks) are used for retrieving the following geophysical cloud properties from GOME and GOME-2 data: cloud fraction (cloud cover), cloud-top pressure (cloud-top height), and cloud optical thickness (cloud-top albedo). OCRA is an optical sensor cloud detection algorithm that uses the PMD devices on GOME / GOME-2 to deliver cloud fractions for GOME / GOME-2 scenes. For more details please refer to relevant peer-review papers listed on the GOME and GOME-2 documentation pages: https://atmos.eoc.dlr.de/app/docs/

  • The PlanetScope satellite constellation, called ‘Flock’, consists of multiple launches of groups of individual Dove satellites into a 400 km orbit. Some of them were launched from the ISS. Therefore, on-orbit capacity is constantly improving in capability or quantity. Each Dove satellite is a CubeSat with a size of 10 x 10 x 34 cm. The complete PlanetScope constellation of approximately 130 satellites is able to image the entire land surface of the Earth every day, equating to a daily collection capacity of 200 million km². In 2014 the first Dove satellites started operationally acquiring images from the earth’s surface. The optical sensors mounted on the individual Dove satellites operate in the visual and near-infrared parts of the electromagnetic spectrum with a spatial resolution between 3 and 5 meters. A third generation of PlanetScope sensors (known as SuperDove or PSB.SD) is currently in orbit and is producing limited quantities of imagery with 5 spectral bands (BGRNIR + Red Edge). These satellites have the potential to produce imagery with 8 separate spectral bands. The RapidEye Science Archive (RESA), which allows Germany-based researchers to apply for free PlanetScope imagery, is operated by the German Satellite Data Archive (D-SDA) of DLR’s Earth Observation Center and can be accessed via the EOWEB Geoportal. New PlanetScope data as well as archive data which is not yet part of the RESA collections can be applied for at Planet Labs Germany GmbH under the RESA contract. For more information see: https://www.planet.com/resa/ This collection comprises the PlanetScope L3A OrthoTile products which are orthorectified as individual 25 km by 25 km tiles referenced to a fixed, standard image tile grid system. The OrthoTile products are radiometrically-, sensor-, and geometrically-corrected and aligned to a cartographic map projection. The Surface Reflectance layer which corrects for the effects of the Earth's atmosphere is included in the product.

  • 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/ This product developed in the frame of the MAPP project (MERIS Application and Regional Products Projects) represents the chlorophyll concentration of the North Sea derived from MERIS data. The product is a cooperative effort of DLR-DFD and the Institute for Coastal Research at the GKSS Research Centre Geesthacht. DFD pre-processed up to the value added level whenever MERIS data for the North Sea region was received and positively checked for a water area large enough for a suitable interpretation. For more details the reader is referred to http://wdc.dlr.de/sensors/meris/ and http://wdc.dlr.de/sensors/meris/documents/Mapp_ATBD_final_i3r0dez2001.pdf This product provides monthly maps.

  • The Global Ozone Monitoring Experiment-2 (GOME-2) instrument continues the long-term monitoring of atmospheric trace gas constituents started with GOME / ERS-2 and SCIAMACHY / Envisat. Currently, there are three GOME-2 instruments operating on board EUMETSAT's Meteorological Operational satellites MetOp-A, -B, and -C, launched in October 2006, September 2012, and November 2018, respectively. GOME-2 can measure a range of atmospheric trace constituents, with the emphasis on global ozone distributions. Furthermore, cloud properties and intensities of ultraviolet radiation are retrieved. These data are crucial for monitoring the atmospheric composition and the detection of pollutants. DLR generates operational GOME-2 / MetOp level 2 products in the framework of EUMETSAT's Satellite Application Facility on Atmospheric Chemistry Monitoring (AC-SAF). GOME-2 near-real-time products are available already two hours after sensing. The operational NO2 total column products are generated using the algorithm GDP (GOME Data Processor) version 4.x integrated into the UPAS (Universal Processor for UV / VIS Atmospheric Spectrometers) processor for generating level 2 trace gas and cloud products. The operational NO2 tropospheric column products are generated using the algorithm GDP (GOME Data Processor) version 4.x for NO2 [Valks et al. (2011)] integrated into the UPAS (Universal Processor for UV / VIS Atmospheric Spectrometers) processor for generating level 2 trace gas and cloud products. The total NO2 column is retrieved from GOME solar back-scattered measurements in the visible wavelength region using the DOAS method. An additional algorithm is applied to derive the tropospheric NO2 column: after subtracting the estimated stratospheric component from the total column, the tropospheric NO2 column is determined using an air mass factor based on monthly climatological NO2 profiles from the MOZART-2 model. For more details please refer to relevant peer-review papers listed on the GOME and GOME-2 documentation pages: https://atmos.eoc.dlr.de/app/docs/

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