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See detailA Multi-Year Combination of Tide Gauge Benchmark Monitoring (TIGA) Analysis Center Products
Hunegnaw, Addisu UL; Teferle, Felix Norman UL

Poster (2015, April 12)

In 2013 the International GNSS Service (IGS) Tide Gauge Benchmark Monitoring (TIGA) Working Group (WG) started their reprocessing campaign, which proposes to re-analyze all relevant Global Positioning ... [more ▼]

In 2013 the International GNSS Service (IGS) Tide Gauge Benchmark Monitoring (TIGA) Working Group (WG) started their reprocessing campaign, which proposes to re-analyze all relevant Global Positioning System (GPS) observations from 1994 to 2013. This re-processed dataset will provide high quality estimates of land motions, enabling regional and global high-precision geophysical/geodetic studies. Several of the individual TIGA Analysis Centres (TACs) have completed processing the full history of GPS observations recorded by the IGS global network, as well as, many other GPS stations at or close to tide gauges, which are available from the TIGA data centre at the University of La Rochelle (www.sonel.org). Following the recent improvements in processing models and strategies, this is the first complete reprocessing attempt by the TIGA WG to provide homogeneous position time series. We report a first multi-year weekly combined solutions from the TIGA Combination Centre (TCC) at the University of Luxembourg (UL) using two independent combination software packages: CATREF and GLOBK. These combinations allow an evaluation of any effects from the combination software and of the individual TAC parameters and their influences on the combined solution. Some major results of the UL TIGA multi-year combinations in terms of geocentric sea level changes will be presented and discussed. [less ▲]

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See detailCalibration of the Tide Gauge at King Edward Point, South Georgia Island
Teferle, Felix Norman UL; Hunegnaw, Addisu UL; Woodworth, P L et al

Poster (2015, March 12)

After initial sea level observations in the 1950s, a new pressure tide gauge (Global Sea Level Observing System 187) was installed at King Edward Point (KEP), South Georgia Island, British Overseas ... [more ▼]

After initial sea level observations in the 1950s, a new pressure tide gauge (Global Sea Level Observing System 187) was installed at King Edward Point (KEP), South Georgia Island, British Overseas Territories in the South Atlantic Ocean, in 2008. This was car-ried out as part of the ACCLAIM (Antarctic Circumpolar Current Levels by Altimetry and Island Measurements) programme. In 2013 the KEP Geodetic Observato-ry was established in support of various geoscience applications including the monitor-ing of vertical land movements at KEP. Currently, the observatory consists of two state-of-the-art GNSS stations with local benchmark networks, allowing the height determina-tions from the GNSS antennas to be transferred to the tide gauge and forming a height reference within the International Terrestrial Reference Frame. Finally in 2014, a tide board was added to the tide gauge, which, together with the GNSS and levelling obser-vations, now allows the calibration of the tide gauge. In this study, we will present the results from the calibration of the tide gauge using the GNSS observations from the KEP Geodetic Observatory for the period from February 2013 to present, the levelling campaigns in 2013 and 2014, and geoid undulations de-rived from a seamless combination of the latest GOCO and EGM2008 gravity models. [less ▲]

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See detailAssessment of BLT Tide Gauge Benchmark Monitoring (TIGA) repro2 solutions
Hunegnaw, Addisu UL; Teferle, Felix Norman UL

Poster (2015)

In 2013 the International GNSS Service (IGS) Tide Gauge Benchmark Monitoring (TIGA) Working Group (WG) started their reprocessing campaign, which proposes to re-analyze all relevant Global Positioning ... [more ▼]

In 2013 the International GNSS Service (IGS) Tide Gauge Benchmark Monitoring (TIGA) Working Group (WG) started their reprocessing campaign, which proposes to re-analyze all relevant Global Positioning System (GPS) observations from 1994 to 2013. This re-processed dataset will provide high quality estimates of land motions, enabling regional and global high-precision geophysical/geodetic studies. Several of the individual TIGA Analysis Centres (TACs) have completed processing the full history of GPS observations recorded by the IGS global network, as well as, many other GPS stations at or close to tide gauges, which are available from the TIGA data centre at the University of La Rochelle (www.sonel.org). Following the recent improvements in processing models and strategies, this is the first complete reprocessing attempt by the BLT TIGA Analysis centre to provide homogeneous position time series. We report the quality of the multi-year daily solutions from the consortium of the British Isles continuous GNSS Facility (BIGF) and the University of Luxembourg TIGA Analysis Centres (BLT) based on the Bernese GNSS Software Version 5.2 using a double difference (DD) network processing strategy. [less ▲]

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See detailRecent Activities at the King Edward Point Geodetic Observatory, South Georgia, in Support of TIGA Objectives
Teferle, Felix Norman UL; Hunegnaw, Addisu UL; Williams, Simon et al

Poster (2014, July 26)

In 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Georgia, South Atlantic Ocean, in support of geoscience applications. South Georgia Island has been a key location for the ... [more ▼]

In 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Georgia, South Atlantic Ocean, in support of geoscience applications. South Georgia Island has been a key location for the seismic, geomagnetic and oceanic global monitoring networks. However, no geodetic permanent monitoring station had been established there despite the lack of observations from this region within the International GNSS Service (IGS) network of Global Navigation Satellite System (GNSS) stations. Currently, the observatory consists of two state-of-the-art GNSS stations (KEPA 42701M001 and KRSA 42702M001) with local benchmark networks, allowing the height determinations from the GNSS antennas to be transferred to the tide gauge (Global Sea Level Observing System 187) and forming a height reference within the International Terrestrial Reference Frame. In this study, we will present an evaluation of the GNSS observations from the KEP Geodetic Observatory for the period from February 2013 to December 2013. We calculate multipath and positioning statistics and compare these to those from IGS stations. We report on the benchmark network and tide board installation, as well as, on the results from the two levelling campaigns carried out to date. For the future it is envisaged that the stations will contribute to the TIGA objective of monitoring vertical land movements at tide gauges, and that KEPA will contribute to the IGS network. [less ▲]

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See detailThe King Edward Point Geodetic Observatory in Support of Sea Level Research
Teferle, Felix Norman UL; Hunegnaw, Addisu UL; Ahmed, Furqan UL et al

Poster (2013, October 28)

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Geor- gia, South Atlantic Ocean, through a University of Luxembourg funded research project and in ... [more ▼]

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Geor- gia, South Atlantic Ocean, through a University of Luxembourg funded research project and in collaboration with the United Kingdom’s National Oceanography Centre, British Antarctic Survey and Unavco, Inc. Due to its remote location in the South Atlantic Ocean, as well as, being one of few subaerial exposures of the Scotia plate, South Georgia Island has been a key location for a number of global monitoring networks, e.g. seismic, geomagnetic and oceanic. However, no geodetic monitoring station has been established, e.g. by the International Global Navigation Satellite System (GNSS) Service (IGS) community, despite the lack of such observations from this region. In this study we give details of the establishment of the KEP Geodetic Observatory, i.e. the installation of the continuous GNSS station KEPA on Brown Mountain and the estab- lishment of a new height datum for the tide gauge through a network of benchmarks at the KEP research station. We will present an evaluation of the GNSS positioning results for the period from February to August 2013 and of the survey/levelling work carried out for the height reference. We will discuss the installation in terms of its potential contributions to sea level observations using tide gauges and satellite altimetry, studies of tectonics, glacio-isostatic adjustment and atmospheric processes. [less ▲]

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See detailPotential Contributions to Geoscience from GNSS Observations of the King Edward Point Geodetic Observatory, South Georgia, South Atlantic Ocean
Teferle, Felix Norman UL; Hunegnaw, Addisu UL; Ahmed, Furqan UL et al

Poster (2013, September 01)

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Georgia, South Atlantic Ocean, through a University of Luxembourg funded research project and in ... [more ▼]

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Georgia, South Atlantic Ocean, through a University of Luxembourg funded research project and in collaboration with the United Kingdom’s National Oceanography Centre, British Antarctic Survey and Unavco, Inc. Due to its remote location in the South Atlantic Ocean, as well as, being one of few subaerial exposures of the Scotia plate, South Georgia Island has been a key location for a number of global monitoring networks, e.g. seismic, geomagnetic and oceanic. However, no geodetic monitoring station has been established, e.g. by the International Global Navigation Satellite System (GNSS) Service (IGS) community, despite the lack of such observations from this region. In this study we will present an evaluation of the GNSS observations from the KEP Geodetic Observatory for the period from February to August 2013. We calculate multipath and positioning statistics and compare these to those from IGS stations. The on-site meteorological data is compared to those from the nearby KEP meteorological station and global numerical weather models, and the impact of these data sets on delay and integrated water vapour estimates will be evaluated. We will discuss the installation in terms of its potential contributions to sea level observations using tide gauges and satellite altimetry, studies of tectonics, glacio-isostatic adjustment and atmospheric processes. [less ▲]

Detailed reference viewed: 93 (14 UL)
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See detailInstallation and First Evaluation of the King Edward Point Geodetic Observatory, South Georgia
Teferle, Felix Norman UL; White, Seth Warren; Foden, Peter R. et al

Poster (2013, May)

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Georgia through a University of Luxembourg funded research project in collaboration with the National ... [more ▼]

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Georgia through a University of Luxembourg funded research project in collaboration with the National Oceanography Centre and the British Antarctic Survey. Due to its remote location in the South Atlantic Ocean as well as being one of few subaerial exposures of the Scotia plate, South Georgia has been a key location for a number of global monitoring networks, e.g. seismic, magnetic and oceanic. However, no geodetic monitoring station had been established previously despite the global network of Global Navigation Satellite System (GNSS) stations is lacking observations from this region. In this presentation we will present a first evaluation of the observations from the KEP Geodetic Observatory for the period from 14 February to 14 April 2013. We calculate multipath characteristics and positioning statistics from precise point positioning (PPP) and discuss the installation in terms of benefits for studies of tectonics and glacio-isostatic adjustment processes. The meteorological data is evaluated by comparison to the data from the existing KEP meteorological station and a widely used numerical weather model. [less ▲]

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Peer Reviewed
See detailStatus of TIGA activities at the British Isles continuous GNSS Facility and the University of Luxembourg
Hunegnaw, Addisu UL; Teferle, Felix Norman UL; Bingley, Richard et al

Scientific Conference (2013)

In 2013 the International GNSS Service (IGS) Tide Gauge Benchmark Monitoring (TIGA) Working Group started their reprocessing campaign which proposes to re-analyse all relevant GPS observations from 1995 ... [more ▼]

In 2013 the International GNSS Service (IGS) Tide Gauge Benchmark Monitoring (TIGA) Working Group started their reprocessing campaign which proposes to re-analyse all relevant GPS observations from 1995 to the end of 2012 in order to provide high quality estimates of vertical land motion for monitoring of sea level changes. The TIGA Working Group will also produce a combined solution from the individual TIGA Analysis Centres (TAC) contributions. The consortium of British Isles continuous GNSS Facility (BIGF) and the University of Luxembourg TAC (BLT) will contribute weekly minimally constrained SINEX solutions from its reprocessing using the Bernese GNSS Software (BSW) version 5.2 and the University of Luxembourg will also act as a TIGA Combination Centre (TCC). The BLT will generate two solutions, one based on BSW5.2 using a network double difference (DD) strategy and a second one based on BSW5.2 using a Precise Point Positioning (PPP) strategy. In the DD strategy we have included all IGb08 core stations in order to achieve a consistent reference frame implementation. As an initial test for the TIGA combination, all TACs agreed to provide weekly SINEX solutions for a four-week period in December 2011. Taking these individual TAC solutions the TCC has computed a first combination using two independent combination software packages: CATREF and GLOBK. In this study we will present preliminary results from the BLT reprocessing and from the combination tests. [less ▲]

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See detailA method of error adjustment for marine gravity with application to Mean Dynamic Topography in the northern North Atlantic
Hunegnaw, Addisu UL; Hipkin, Roger; Edwards, John

in Journal of Geodesy (2009), 83(2), 161-174

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See detailAbsolute flow field estimation for the Nordic seas from combined gravimetric, altimetric, and in situ data
Hunegnaw, Addisu UL; Siegismund, Frank; Hipkin, Roger et al

in Journal of Geophysical Research. Oceans (2009), 114(C2),

Detailed reference viewed: 62 (4 UL)
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See detailCombining altimetric/gravimetric and ocean model mean dynamic topography models in the GOCINA region
Knudsen, Per; Andersen, Ole; Forsberg, Rene et al

in International Association of Geodesy Symposia (2007)

Detailed reference viewed: 109 (2 UL)