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Heligoland GNSS hourly time series positioning for 2017-2021

This dataset includes 1-hour GNSS coordinate product processed by GFZ. The observations are from the two GNSS station installed by BKG on the small offshore island of Heligoland in the North Sea. These products are hourly position time series (North, East and Vertical). The 30-second daily RINEX files since 2020 are downloaded from BKG. Together with 5 IGS stations in Europe, the collected RINEX data are processed with the Earth Parameter and Orbit System (EPOS) software from GFZ. The EPOS software uses un-difference carrier phase and pseudo-range observables from GPS and GLONASS L1 and L2 frequencies. They formed an ionosphere-free linear combination to remove the first-order ionosphere effect in the observation. The phase center variation (PCV/PCO) of the satellite and ground station antenna are corrected by IGb14. The station deformation caused by ocean tide loading is modeled by the FES2004 model. Apriori zenith hydro-static/non-hydro-static delay is obtained using the Global Pressure and Temperature model (GPT2) and Vienna mapping functions (VMF) in a 6-hour grid file database. To ensure consistency in the GNSS data analysis, we took the GNSS precise satellite orbits as well as clock products from the 2nd reprocessed (before 2014) and routine (since 2015) yield by EPOS software. The same station parameters are set up as used for the GNSS orbit and clock estimation. All the GNSS data were processed in units of 24 hours periods. The estimated parameters are (i) the receiver clock error for every epoch as white noise, (ii) the hourly station coordinates, (iii) daily tropospheric gradients, (iv) the daily inter-system clock bias for GLONASS, and (v) 2-hour tropospheric wet zenith delays with random-walk constrain.

Multi-frequency, multi-constellation, GNSS observations at low-cost tectonic GNSS stations in Greece

The TectoVision GNSS network in Greece was set up using European Research Council funding in partnership between German and Greek institutions. The project aims to deepen our understanding of suspected microplate motions in Greece. A total of 72 GNSS stations are planned for the TectoVision network. Two types of GNSS station equipment is used, reflected by the 4 character station ID. Stations with ID beginning with 'TT' were installed using the tinyBlack receiver. The stations with ID beginning 'TM' were set up using the Minimum Cost GNSS System (MCGS) design. RINEX (v3.05 as of May 2024) data at 30 seconds sampling interval are provided. Most of the data are sent over mobile internet via routers that are connected to the receivers via LAN cable. If required, the RINEX files can be converted to other versions using the GFZ software GFZRNX (Nischan, 2016). Raw observation data can be made available upon specific request. Hardware: The GFZ developed tinyBlack receiver combines cost efficient L2C GNSS receivers (here Swiftnav Piksi) with PC-based data logger package, internal storage, and interfaces. The control software is designed for remote operation ensuring long-term continuous tracking. The tinyBlack receivers provided by the GFZ spin-off maRam UG (Germany) are installed in combination with Harxon GPS500 survey antennas. The tinyBlack stations provide GPS (L1/L2), GLONASS (G1/G2), and Galileo (E1/E5b) data. The low-cost MCGS stations are coming in 2 versions from a GNSS technology transfer project at GFZ. Both versions operate a ublox F9P receiver and an integrated chip-antenna with a pyramidal antenna radome. One version provides GPS (L1/L2), Glonass (G1/G2), Galileo (E1/E5b) and also Beidou (B1/B2) data. The other version (currently only 3 systems installed) is designed for low power operation in remote areas with data telemetry over a narrrow bandwidth radio link. This version delivers only GPS (L1/L2) data without doppler observations at a reduced data rate of 60 seconds. Monumentation: There is a variety of monumentation for these stations, with the design of the monumentation being low-cost. Most are connected to a thread that is attached to a stainless steel pin which is glued into masonry or bedrock. Most sites are installed on rooftops of public buildings. The MCGS is sometimes clamped to an existing sturdy pole connected to the roof of the building. Some stations are connected to an extending stainless-steel arm that we have drilled into the side of a building. Photos of the station are provided with the standard GNSS station log-files (as metadata). If the instrumentation at existing monuments is later changed to other hardware types, the station ID retain the original TT and TM 4-character IDs. Metadata: Station-specific metadata records are stored in IGS sitelog files available via ftp.

EOP predictions collected during the operational phase of the Second Earth Orientation Parameters Prediction Comparison Campaign

This dataset contains predictions of Earth orientation parameters (EOP) submitted during the Second Earth Orientation Parameters Prediction Comparison Campaign (2nd EOP PCC). The 2nd EOP PCC has been carried out by Centrum Badań Kosmicznych Polskiej Akademii Nauk CBK PAN in Warsaw in cooperation with the GFZ German Research Centre for Geosciences in Potsdam (Germany) and under the auspices of the International Earth Rotation and Reference Systems Service (IERS) within the IERS Working Group on the 2nd EOP PCC. The purpose of the campaign was to re-assess the current capabilities of EOP forecasting and to find most reliable prediction approaches. The operational part of the campaign lasted between September 1, 2021 and December 28, 2022. Throughout the duration of the 2nd EOP PCC, registered campaign participants submitted forecasts for all EOP parameters, including dX, dY, dPsi, dEps (components of celestial pole offsets), polar motion, differences between universal time and coordinated universal time, and its time-derivative length-of-day change. These submissions were made to the EOP PCC Office every Wednesday before the 20:00 UTC deadline. The predictions were then evaluated once the geodetic final EOP observations from the forecasted period became available. Each participant could register more than one method, and each registered method was assigned an individual ID, which was used, e.g., for file naming. The dataset contains text files with predicted parameters as submitted by campaign participants and MATLAB file which is a database with all correct predictions from each participant loaded into a structure. Campaign overview and first results are described in the following articles: Śliwińska, J., Kur, T., Wińska, M., Nastula, J., Dobslaw, H., & Partyka, A. (2022). Second Earth Orientation Parameters Prediction Comparison Campaign (2nd EOP PCC): Overview. Artificial Satellites, 57(S1), 237–253. https://doi.org/10.2478/arsa-2022-0021 Kur, T., Dobslaw, H., Śliwińska, J., Nastula, J., & Wińska, M. (2022). Evaluation of selected short ‑ term predictions of UT1 ‑ UTC and LOD collected in the second earth orientation parameters prediction comparison campaign. Earth, Planets and Space, 74. https://doi.org/10.1186/s40623-022-01753-9

Survey mode GPS data in the West Pamir, Tajikistan, Central Asia, 2013-2016

We have installed 20 new Global Positioning System (GPS) markers in the West Pamir and the Tajik Depression and measured 25 markers once a year between 2013 and 2016 in survey mode. The stations are positioned along two dense NW-SE oriented profiles with an average spacing of 5-10 km. The profiles cross the Darvaz and the Vakhsh/Ilyak fault and thus monitor the recent slip of these two profiles, which are expected to accommodate the gravity-driven westward extrusion of the West Pamir into the Tajik Depression. Some of the stations include millimeter to centimeter offsets potentially caused by the 2015 Mw7.2 Sarez, Pamir, earthquake.

Survey mode GNSS data, acquired 2014-2019 in the Afghan Hindu Kush and across northern Pamir margin, Central Asia

We have installed 19 new Global Navigation Satellite System (GNSS) markers in the Hindu Kush (NE-Afghanistan) and the North Pamir front (Alai valley) and measured a total of 25 new and existing markers, if possible annually between 2014 and 2020 in survey mode. The stations are positioned along three profiles crossing the NE-striking Panjsheer fault and N-striking Badakhshan fault in the Hindu Kush, and the E-striking Pamir thrust system at the Trans Alai Range. The Hindu Kush survey data are the first of their kind in Afghanistan. The Pamir profile densifies a 1 Hz-GNSS profile that was installed in the Altyndara valley in 2013-2015; the GNSS time-series are affected by the 2015 Mw7.2 Sarez, Central Pamir, earthquake and probably the 2016 Mw6.4 Sary-Tash earthquake. The data are presented in receiver independent exchange (RNX) format and complemented by logsheets, field photos and a technical report describing the surveys in more detail.

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