Evaluating seasonal loading models and their impact on global and regional reference frame alignment

We have established a stable regional geodetic reference frame using long-history (13.5 years on average) observations from 55 continuously operated Global Navigation Satellite System (GNSS) stations adjacent to the Gulf of Mexico (GOM). The regional reference frame, designated as GOM20, is aligned in origin and scale with the International GNSS Reference Frame 2014 (IGS14). The primary product from this study is the seven-parameters for transforming the Earth-Centered-Earth-Fixed (ECEF) Cartesian coordinates from IGS14 to GOM20. The frame stability of GOM20 is approximately 0.3 mm/year in the horizontal directions and 0.5 mm/year in the vertical direction. The regional reference frame can be confidently used for the time window from the 1990s to 2030 without causing positional errors larger than the accuracy of 24-h static GNSS measurements. Applications of GOM20 in delineating rapid urban subsidence, coastal subsidence and faulting, and sea-level rise are demonstrated in this article. According to this study, subsidence faster than 2 cm/year is ongoing in several major cities in central Mexico, with the most rapid subsidence reaching to 27 cm/year in Mexico City; a large portion of the Texas and Louisiana coasts are subsiding at 3 to 6.5 mm/year; the average sea-level-rise rate (with respect to GOM20) along the Gulf coast is 2.6 mm/year with a 95% confidence interval of ±1 mm/year during the past five decades. GOM20 provides a consistent platform to integrate ground deformational observations from different remote sensing techniques (e.g., GPS, InSAR, LiDAR, UAV-Photogrammetry) and ground surveys (e.g., tide gauge, leveling surveying) into a unified geodetic reference frame and enables multidisciplinary and cross-disciplinary research.

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Quantum reverse engineering and reference-frame alignment without nonlocal correlations

Physical Review A ◽

10.1103/physreva.70.030301 ◽

2004 ◽

Vol 70 (3) ◽

Cited By ~ 42

Author(s):

E. Bagan ◽

M. Baig ◽

R. Muñoz-Tapia

Keyword(s):

Reverse Engineering ◽

Reference Frame ◽

Frame Alignment ◽

Nonlocal Correlations

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GPS geodetic infrastructure for subsidence and fault monitoring in Houston, Texas, USA

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-382-11-2020 ◽

2020 ◽

Vol 382 ◽

pp. 11-18 ◽

Cited By ~ 1

Author(s):

Gonzalo Agudelo ◽

Guoquan Wang ◽

Yuhao Liu ◽

Yan Bao ◽

Michael J. Turco

Keyword(s):

Reference Frame ◽

Urban Areas ◽

Ground Deformation ◽

University Of Houston ◽

Fault Monitoring ◽

Global Positioning ◽

The Stability ◽

Continuous Gps ◽

The University ◽

Regional Reference

Abstract. Houston, Texas, is one of the earliest urban areas to employ Global Positioning System (GPS) technology for land subsidence and fault monitoring. As of 2020, the University of Houston and the Harris-Galveston Subsidence District have integrated over 230 permanent GPS stations into their routine GPS data processing for regional subsidence and fault monitoring. This article summarizes the GPS geodetic infrastructure in the Greater Houston region. The infrastructure is comprised of two components: a dense GPS network (HoustonNet) and a stable regional reference frame (Houston20). Houston20 is realized by 25 long-history (>8 years) continuous GPS stations located outside the subsiding area and is aligned in origin and scale with the International GNSS Reference Frame 2014 (IGS14). The stability of the regional reference frame is below 1 mm yr−1 in all three directions. GPS-derived ground deformation rates (2010–2019) within the Greater Houston region are also presented in this article.

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First results of the Nordic and Baltic GNSS Analysis Centre

Journal of Geodetic Science ◽

10.1515/jogs-2018-0005 ◽

2018 ◽

Vol 8 (1) ◽

pp. 34-42 ◽

Cited By ~ 3

Author(s):

Sonja Lahtinen ◽

Häkli Pasi ◽

Lotti Jivall ◽

Christina Kempe ◽

Karin Kollo ◽

...

Keyword(s):

Reference Frame ◽

Network Effect ◽

Local Analysis ◽

Main Interest ◽

Frame Alignment ◽

Isostatic Adjustment ◽

Baltic Countries ◽

First Results ◽

Combined Solution ◽

The Common

Abstract The Nordic Geodetic Commission (NKG) has launched a joint NKG GNSS Analysis Centre that aims to routinely produce high qualityGNSS solutions for the common needs of the NKG and the Nordic and Baltic countries. A consistent and densified velocity field is needed for the constraining of the gla-cial isostatic adjustment (GIA) modelling that is a key component of maintaining the national reference frame realisations in the area. We described the methods of the NKG GNSS Analysis Centre including the defined processing setup for the local analysis centres (LAC) and for the combination centres.We analysed the results of the first 2.5 years (2014.5-2016). The results showed that different subnets were consistent with the combined solution within 1-2 mm level. We observed the so called network effect affecting our reference frame alignment. However, the accuracy of the reference frame alignment was on a few millimetre level in the area of the main interest (Nordic and Baltic Countries). TheNKGGNSS AC was declared fully operational in April 2017.

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CARIB18: A Stable Geodetic Reference Frame for Geological Hazard Monitoring in the Caribbean Region

Remote Sensing ◽

10.3390/rs11060680 ◽

2019 ◽

Vol 11 (6) ◽

pp. 680 ◽

Cited By ~ 8

Author(s):

Guoquan Wang ◽

Hanlin Liu ◽

Glen Mattioli ◽

Meghan Miller ◽

Karl Feaux ◽

...

Keyword(s):

Reference Frame ◽

Vertical Direction ◽

Differential Method ◽

Plate Motion ◽

Caribbean Region ◽

Geological Hazard ◽

International Gnss Service ◽

The Caribbean ◽

Regional Reference

We have developed a Stable Caribbean Reference Frame 2018 (CARIB18) using long-term continuous observations from 18 continuously operating Global Positioning System (GPS) stations fixed on the margins of the stable portion of the Caribbean plate. The frame stability of CARIB18 is approximately 0.7 mm/year in the horizontal direction and 0.9 mm/year in the vertical direction. A method that employs a total of seven parameters for transforming positional time series from a global reference frame (IGS14) to a regional reference frame is introduced. The major products from this study include the seven parameters for realizing CARIB18 coordinates and three-component site velocities of 250 continuous GPS stations (>3 years) with respect to CARIB18. Geological hazard monitoring using GPS has traditionally been performed using the carrier-phase differential method that requires single or multiple reference stations to be simultaneously operated in the field. CARIB18 allows for precise geological hazard monitoring using stand-alone GPS, which substantially reduces field costs and simplifies logistics for long-term geological hazard monitoring. Applications of CARIB18 in plate motion, post-seismic, and volcano monitoring and research are demonstrated in this article. The regional reference frame will be periodically updated every few years with more reference stations and longer periods of observations to mitigate the degradation of the frame over time and will be synchronized with the updates of the International GNSS Service (IGS) IGS reference frame.

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