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# 11
Encarnacao, Joao • Visser, Pieter • Jaeggi, Adrian • Bezdek, Ales • Mayer-Gürr, Torsten • (et. al.)
Abstract: Although the knowledge of the gravity of the Earth has improved considerably with CHAMP, GRACE and GOCE satellite missions, the geophysical community has identified the need for the continued monitoring of its time-variable component with the purpose of estimating the hydrological and glaciological yearly cycles and long-term trends. Currently, the GRACE-FO satellites are the sole provider of this data, while previously the GRACE mission collected these data for 15 years. Between the GRACE and GRACE-FO data periods lies a gap spanning from July 2017 to May 2018, while the Swarm satellites have collected gravimetric data with its GPS receivers since December 2013. This project aims at providing high-quality gravity field models from Swarm data that constitute an alternative and independent source of gravimetric data, which could help alleviate the consequences of the 10-month gap between GRACE and GRACE-FO, as well as the short gaps in the existing GRACE and GRACE-FO monthly time series. The geodetic community has realized that the combination of the different gravity field solutions is superior to any individual model. This project exploits this fact and delivers to the highest quality monthly-independent gravity field models, resulting from the combination of 4 different gravity field estimation approaches. All solutions are unconstrained and estimated independently from month to month. Preliminary comparison with GRACE data has demonstrated that the signal in the Swarm gravity field models is restricted to degrees 12-15 and below, while the temporal correlations decrease considerably above degree 10. The 750km smoothed models are suitable to retrieve the global annual temporal variations of Earth's gravity field and the agreement with GRACE over large basins (e.g. Amazon, Congo-Zambezi, Ganges-Brahmaputra) is within 1cm RMS in terms of Equivalent Water Height. The global RMS relative to a bias, trend, an annual and semi-annual model derived from GRACE over deep ocean areas (those roughly 1000km from shorelines) is under 1mm geoid height during periods of low ionospheric activity. More information about this project can be found at https://www.researchgate.net/project/Multi-approach-gravity-field-models-from-Swarm-GPS-data and ESA's Swarm DISC (the Data, Innovation and Science Cluster) Website (https://earth.esa.int/web/guest/missions/esa-eo-missions/swarm/activities/scientific-projects/disc#MAGF). This project is funded by ESA via the Swarm DISC, Sub-Contract No. SW-CO-DTU-GS-111.
# 12
Rother, Martin • Michaelis, Ingo
Abstract: Electron density and electron temperature time series from 'LEO' satellite 'CHAMP' for the CHAMP mission period at satellite position in low time resolution of 15 second and given in daily files. This are processed readings from the Planar Langmuir probe, which, in normal flight mode, was exposed in flight direction at the front of the `CHAMP' satellite body. The files are formatted as simple 'ASCII'-listings with white-space delimited columns. The full product and format descriptions are provided in the associated Scientific Technical Report - Data (GFZ Section 2.3, 2019. http://doi.org/10.2312/GFZ.b103-19104).
CHAMP (CHAllenging Minisatellite Payload) was a German small satellite mission for geoscientific and atmospheric research and applications, managed by GFZ . With its highly precise, multifunctional and complementary payload elements (Overhauser scalar magnetometer (OVM) and Fluxgate vector magnetometer (FGM), accelerometer, star sensor (ASC), GPS receiver, laser retro reflector, ion drift meter) and its orbit characteristics (near polar, low altitude, long duration) CHAMP generated highly precise gravity and magnetic field measurements simultaneously for the first time and over a 10 years period. CHAMP launched by a Russian COSMOS launch vehicle on July 15, 2000 and an initial altitude of 454 km. The mission ended on September 19 2010 after ten years, two month and four days, or after 58277 orbits.
# 13
Rother, Martin • Michaelis, Ingo
Abstract: This is a Level 3 data daily file product from various scientific and utility sensors on board of the `LEO' satellite 'CHAMP' with magnetic field data given by a time resolution of 1 Hz. Thise Level 3 data type is build to hold and merge finally corrected data, focusing on mature data calibration and corrections -- as well as internal consistency. This Level 3 data product is intended to supersede the various Level 2 versions with calibrated magnetic field readings from the CHAMP mission distributed hitherto and should be fitted for scientific use, assembling time series of scalar magnetic field values (but not directly readings from the scalar Overhauser sensor), vector magnetic field data from the boom-mounted Fluxgate 'FGM' sensors and attitude data from the ('ASC') boom-mounted Star Cameras. The vector data are given both in the satellite-bound sensor ('FGM') system and the Earth Centered Earth Fixed local 'NEC' (North-East-Center) system. The attitude time series, processed and cleaned, are represented by quaternions describing the satellite attitude related to the celestial system. The readings of the scalar OVM (Overhauser) absolute magnetometer at the top of the boom are not supplied directly, but were used during calibration of the vector magnetometer readings. The files with daily time coverage are in the (binary and self-describing) 'CDF' file format and accompanied, beside the generic 'CDF'-format timestamp, by the satellite's geocentric positions and utility information like quality flags. The full product and format descriptions are provided in the associated Scientific Technical Report - Data (GFZ Section 2.3, 2019. http://doi.org/10.2312/GFZ.b103-19104).
CHAMP (CHAllenging Minisatellite Payload) was a German small satellite mission for geoscientific and atmospheric research and applications, managed by GFZ. With its highly precise, multifunctional and complementary payload elements (Overhauser scalar magnetometer (OVM) and Fluxgate vector magnetometer (FGM), accelerometer, star sensor (ASC), GPS receiver, laser retro reflector, ion drift meter) and its orbit characteristics (near polar, low altitude, long duration) CHAMP generated highly precise gravity and magnetic field measurements simultaneously for the first time and over a 10 years period. CHAMP launched by a Russian COSMOS launch vehicle on July 15, 2000 and an initial altitude of 454 km. The mission ended on September 19 2010 after ten years, two month and four days, or after 58277 orbits.
# 14
Rother, Martin • Michaelis, Ingo
Abstract: Time series of processed, cleaned attitude readings in quaternion format of the two boom-mounted 'ASC' star sensors of the 'LEO' satellite 'CHAMP', describing the satellite system attitude in respect to the celestial background. The nominal time resolution of the time series in the 'ASCII'-file listing is 1 Hz. The full product and format descriptions are provided in the associated Scientific Technical Report - Data 19/10 (GFZ Section 2.3, 2019. http://doi.org/10.2312/GFZ.b103-19104).
CHAMP (CHAllenging Minisatellite Payload) was a German small satellite mission for geoscientific and atmospheric research and applications, managed by GFZ . With its highly precise, multifunctional and complementary payload elements (Overhauser scalar magnetometer (OVM) and Fluxgate vector magnetometer (FGM), accelerometer, star sensor (ASC), GPS receiver, laser retro reflector, ion drift meter) and its orbit characteristics (near polar, low altitude, long duration) CHAMP generated highly precise gravity and magnetic field measurements simultaneously for the first time and over a 10 years period. CHAMP launched by a Russian COSMOS launch vehicle on July 15, 2000 and an initial altitude of 454 km. The mission ended on September 19, 2010, after ten years, two month and four days, or after 58277 orbits.
# 15
Rother, Martin • Michaelis, Ingo
Abstract: Earth's magnetic field vector time series from `LEO' satellite 'CHAMP' for the 'CHAMP' mission period in high, unaveraged 50 Hz time resolution, using measurements from the FGM vector magnetometers and `ASC' Star Sensors on the mid-boom optical bench. The vector data are corrected and calibrated (by using the Overhauser scalar magnetometer as reference). The magnetic field vector data are given both in the satellite-bound sensor (`FGM') system and in the Earth Centered Earth Fixed local `NEC' (North-East-Center) system. For the latter the attitude time series (`ASC'), processed and cleaned, represented by quaternions describing the satellite attitude related to the celestial system, were used for the transformation. The files with daily time coverage are in the (binary and self-describing) `CDF' file format and accompanied, beside the `CDF'-format generic timestamp, by the satellite's geocentric positions and utility information like quality flags. The full product and format descriptions are provided in the associated Scientific Technical Report - Data (GFZ Section 2.3, 2019. http://doi.org/10.2312/GFZ.b103-19104).
CHAMP (CHAllenging Minisatellite Payload) was a German small satellite mission for geoscientific and atmospheric research and applications, managed by GFZ . With its highly precise, multifunctional and complementary payload elements (Overhauser scalar magnetometer (OVM) and Fluxgate vector magnetometer (FGM), accelerometer, star sensor (ASC), GPS receiver, laser retro reflector, ion drift meter) and its orbit characteristics (near polar, low altitude, long duration) CHAMP generated highly precise gravity and magnetic field measurements simultaneously for the first time and over a 10 years period. CHAMP launched by a Russian COSMOS launch vehicle on July 15, 2000 and an initial altitude of 454 km. The mission ended on September 19 2010 after ten years, two month and four days, or after 58277 orbits.
# 16
Ruhm, Jonathan • Böhnert, Tim • Weigend, Maximilian • Stoll, Alexandra • Merklinger, Felix F. • (et. al.)
Abstract: The dataset contains (1) floristic and vegetation data along an altitudinal gradient for four study transects: Quebrada Aroma, Altos de Pica, Quebrada Blanca and Tambillo. Additional information regarding the plot setup is provided. (2) A list of Literature used for the identification of recorded specimens is added. Further, we provide (3) presence/absence data of 649 plant species for 21 localities in northern Chile and southern Peru.
# 17
Ziegler, Moritz O.
Abstract: In geosciences 3D geomechanical-numerical models are used to estimate the in-situ stress state. In such a model each geological unit is populated with the rock properties Young’s module, Poisson ratio, and density. Usually, each unit is assigned a single set of homogeneous properties. However, variable rock properties are observed and expected within the same geological unit. Even in small volumes large variabilities may. The Python script HIPSTER (Homogeneous to Inhomogeneous rock Properties for Stress TEnsor Research) provides an algorithm to include inhomogeneities in geomechanical-numerical models that use the solver Abaqus®. The user specifies the mean values for the rock properties Young's module, Poisson ratio and density, and their variability for each geological unit. The variability of the material properties is individually defined for each of the three rock properties in each geological layer. For each unit HIPSTER generates a normal or uniform distribution for each rock property. From these distri-butions for each single element HIPSTER draws individual rock properties and writes them to a separate material file. This file defines different material properties for each element. The file is included in the geomechanical-numerical analysis solver deck and the numerical model is solved as usual. HIPSTER is fully documented in the associated data report (Ziegler, 2019, http://doi.org/10.2312/WSM.2019.003) and can also be accessed at Github (http://github.com/MorZieg/hipster)
# 18
Kaplan, Nils Hinrich • Sohrt, Ernestine • Blume, Theresa • Weiler, Markus
Abstract: Version history17. July 2019: release of Version 2.0. This version includes additionally the catchment boundaries provided as subfolder of geodata.zip. The version 1.0 is available in the "previous-versions" subfolder via the Data Download link. The time series did not change and are not included in the V1.0 zip folder. Data descriptionWe used different sensing techniques including time-lapse imagery, electric conductivity and stage measurements to generate a combined dataset of presence and absence of streamflow within a large number of nested sub-catchments in the Attert Catchment, Luxembourg. The first sites of observation were established in 2013 and successively extended to a total number of 182 in 2016 as part of the project “Catchments As Organized Systems” (CAOS, Zehe et al., 2014). Setup for time-lapse imagery measurements was inspired by Gilmore et al. (2013) while the setup for EC-sensor was proposed by Chapin et al. (2014). Temporal resolution ranged from 5 to 15 minutes intervals. Each single dataset was carefully processed and quality controlled before the time interval was homogenized to 30 minutes. The dataset provides valuable information of the dynamics of a meso-scale stream network in space and time. The Attert basin is located in the border region of Luxembourg and Belgium and covers an area of 247 km². The elevation of the catchment ranges from 245 m a.s.l. in Useldange to 549 m a.s.l. in the Ar-dennes. Climate conditions across the catchment are rather similar in terms of temperature and pre-cipitation. Hydrological regimes are mainly driven by seasonal fluctuations in evapotranspiration caus-ing flow to cease in intermittent reaches during dry periods. The catchment covers three predominant geologies: Slate, Marls and Sandstone. The dataset features data from catchments covering all geologi-cal characteristics from single geology to mixed geology. It can be used to test and evaluate hydrologic models, but also for the assessment of the intermittent stream ecosystem in the Attert basin.
Time-lapse Imagery Dörr Snapshot Mini 5.0 consumer wildlife cameras were used for time-lapse imagery. Time lapse mon-itoring was realized with the internal software with a temporal resolution of 15 minutes. Cameras were mounted at trees or structures close to the channel. For improved image analysis a gauging plate was installed in the channel. This method was closely related to a time-lapse camera gauging system published by Gilmore et al. (2013). EC-sensorsOnset HOBO Pendant waterproof temperature and light data logger (Model UA-002-64, Onset Com-puter Corp, Bourne, MA, USA) with modified light sensor to measure electric conductivity were used to monitor electric conductivity (EC) as proposed by Chapin et al. (2014). EC values were classified into no-flow situations for EC-values below 25microSi/cm and flow situation for EC-values above 25microSi/cm. Conventional GaugesConventional Gauges are divided into two sub-datasets. Data from ID values CG1 to CG11 were de-rived from water level data measured by METER/Decagon CTD pressure transducers in stilling wells. Data from ID values CG 12 to CG 18 were derived from discharge values measured by the Luxembourg Institute of Science and Technology (LIST). GeodataGeodata comprises of information on proportional shares of geological units in the catchment, the average slope in the catchment and the catchment area upstream of each site. Geological information is derived from a geological map (1:25.000) provided by the Administration des ponts et chaussées Service géologique de l'Etat, Luxembourg (2012). The the original map was created from 1947-1949. GIS analyses were performed using QGIS and SAGA on a 15 m resolution digital elevation model (DEM), which is based on a combined 5m resolution LIDAR scan of Luxembourg (Modèle Numérique de Terrain de Luxembourg, Le Gouvernement du Grand-Duché de Luxembourg, Administration du cadastre et de la topographie, 5m LIDAR, https://data.public.lu/en/datasets/bd-l-mnt5/) and 10m resolution LIDAR scan of Belgium (Relief de la Wallonie - Modèle Numérique de Surface, Service public de Wallonie, Département de la Géomatique. 10m LIDAR, http://geoportail.wallonie.be/catalogue/6029e738-f828-438b-b10a-85e67f77af92.html). The generat-ed 15m DEM has been pre-processed by burning in the digitalized stream network ( min. border cell method, epsilon = 3) and filling sinks (Wang Lui algorithm, minimum slope = 0.1°). The catchment area was calculated by using the pre-processed DEM with 15m resolution and the catchment area recursive tool from the SAGA toolbox using the D-8 method. The same DEM was used to calculate the average slope of each catchment. The “slope, aspect, curvature” tool from the SAGA toolbox was used to calcu-late the slope [radians] with the 9 parameter 2nd order polynom method (Zevenbergen & Thorne 1987) which uses a 3x3 pixel window of the DEM to calculate the slope. Catchment boundaries for each site are included as shape files. These shapefiles were calculated with the Watershed tool from the ArcGIS Hydrology toolbox using a flow direction raster as input which was derived from the Flow Direction tool (ArcGIS Hydrology toolbox) from the DEM described above. Raster output was trans-formed to shape files without simplification of the geometry (subfolder: boundaries).
# 19
Voigt, Claudia • Klipsch, Swea • Herwartz, Daniel • Chong, Guillermo • Staubwasser, Michael
Abstract: This dataset comprises results of total soil chemical analyses of bulk sediment samples sampled along latitudinal and longitudinal transects between 19 - 25°S and 68.5 - 70.5°W (Atacama Desert, Chile). The soil samples consist of poorly cemented thin surface crusts, powdery chuca, and subsurface concretions from the transition to the costra. The analyses include: X-ray diffraction analyses, thermogravimetric analyses (gypsum content), ion concentration data (Na, Ca, K, Mg, Cl, SO4, NO3), organic/inorganic carbon data.
# 20
Radosavljevic, Boris • Quinteros, Javier • Bertelmann, Roland • Hemmleb, Susanne • Elger, Kirsten • (et. al.)
Abstract: This publication contains tabular summaries of the data management survey carried out at the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, as well as the diagrams of individual questions shown in Radosavljevic et al. (2019). The online survey was conducted from August 27 to September 27, 2019. The survey design leaned on similar surveys carried out at German universities and research institutions (e.g. Paul-Stüve et al., 2015; Simukovic et al., 2013) The survey queried aspects of the complete data life cycle - from the planning stage to reuse in 37 questions: 16 single response (SR); where only one answer was possible, and 20 multiple response (MR) where multiple answers could be selected, and one free text question. Research staff at all career levels was the target audience for the survey. Invitations to participate in the completely anonymous online survey were sent out over the general GFZ lists. The survey was carried out with the Questback EFS Survey platform. 226 attempts, out of 411, led to completed questionnaires corresponding to a 55% completion rate. Compared to the target audience at GFZ, the participation rate amounted to ca. 24%. However, less than 20% of employees classified as infrastructure support employees or bachelor’s and master’s students and student assistants completed the survey. Replies falling into these categories were grouped into “others” in the report as well as in the data presented here. Data summaries are given in two tab-separated tables corresponding to response counts or percentage for each question. These are grouped by department, role and employment length. Questions 5 and 34 were ranking questions and the corresponding responses in the percentages table represent arithmetic means of the replies for these questions – not percentages. The response counts for these question are presented in the “Counts” table. Free text replies are omitted from these results. In addition, the diagrams of individual questions are presented Radosavljevic et al. (2019) are also provided in png and pdf formats.
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