Monitoring of Ground Movement and Groundwater Changes in London Using InSAR and GRACE

Groundwater-induced land movement can cause damage to property and resources, thus its monitoring is very important for the safety and economics of a city. London is a heavily built-up urban area and relies largely on its groundwater resource and thus poses the threat of land subsidence. Interferometric Synthetic Aperture Radar (InSAR) can facilitate monitoring of land movement and Gravity Recovery and Climate Experiment (GRACE) gravity anomalies can facilitate groundwater monitoring. For London, no previous study has investigated groundwater variations and related land movement using InSAR and GRACE together. In this paper, we used ENVISAT ASAR C-band SAR images to obtain land movement using Persistent Scatterer InSAR (PSInSAR) technique and GRACE gravity anomalies to obtain groundwater variations between December 2002 and December 2010 for central London. Both experiments showed long-term, decreasing, complex, non-linear patterns in the spatial and temporal domain. The land movement values varied from −6 to +6 mm/year, and their reliability was validated with observed Global Navigation Satellite System (GNSS) data, by conducting a two-sample t-test. The average groundwater loss estimated from GRACE was found to be 9.003 MCM/year. The ground movement was compared to observed groundwater values obtained from various boreholes around central London. It was observed that when large volumes of groundwater is extracted then it leads to land subsidence, and when groundwater is recharged then surface uplift is witnessed. The results demonstrate that InSAR and GRACE complement each other and can be an excellent source of monitoring groundwater for hydrologists.

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Spatial Analysis of Land Subsidence in the San Luis Potosi Valley Induced by Aquifer Overexploitation Using the Coherent Pixels Technique (CPT) and Sentinel-1 InSAR Observation

Remote Sensing ◽

10.3390/rs12223822 ◽

2020 ◽

Vol 12 (22) ◽

pp. 3822

Author(s):

María Inés Navarro-Hernández ◽

Roberto Tomás ◽

Juan M. Lopez-Sanchez ◽

Abraham Cárdenas-Tristán ◽

Jordi J. Mallorquí

Keyword(s):

Land Subsidence ◽

Strong Relationship ◽

Satellite System ◽

Groundwater Withdrawal ◽

Persistent Scatterer Interferometry ◽

San Luis ◽

Persistent Scatterer ◽

San Luis Potosi ◽

Global Navigation Satellite ◽

San Luis Potosí

The San Luis Potosi metropolitan area has suffered considerable damage from land subsidence over the past decades, which has become visible since 1990. This paper seeks to evaluate the effects of groundwater withdrawal on land subsidence in the San Luis Potosi Valley and the development of surface faults due to the differential compaction of sediments. For this purpose, we applied the Coherent Pixels Technique (CPT), a Persistent Scatterer Interferometry (PSI) technique, using 112 Sentinel-1 acquisitions from October 2014 to November 2019 to estimate the deformation rate. The results revealed that the deformation areas in the municipality of Soledad de Graciano Sánchez mostly exhibit subsidence values between −1.5 and −3.5 cm/year; whereas in San Luis Potosi these values are between −1.8 and −4.2 cm/year. The PSI results were validated by five Global Navigation Satellite System (GNSS) benchmarks available, providing a data correlation between the results obtained with both techniques of 0.986. This validation suggests that interferometric derived deformations agree well with results obtained from GNSS data. The strong relationship between trace fault, land subsidence,e and groundwater extraction suggests that groundwater withdrawal is resulting in subsidence induced faulting, which follows the pattern of structural faults buried by sediments.

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Study the Effect of Radio Interference of the EHV Transmission Line on GNSS Signals

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.805-806.851 ◽

2013 ◽

Vol 805-806 ◽

pp. 851-854

Author(s):

Zhi Ge Jia ◽

Zhao Sheng Nie ◽

Wei Wang ◽

Xiao Guan ◽

Di Jin Wang

Keyword(s):

Transmission Line ◽

Transmission Lines ◽

Internal Noise ◽

Field Testing ◽

Satellite System ◽

Field Analysis ◽

Radio Interference ◽

Gnss Receiver ◽

Global Navigation Satellite ◽

Gnss Data

This work describes the field testing process of Global Navigation Satellite System (GNSS) receiver under 220KV, 500KV UHV transmission line and standard calibration field. Analysis for GNSS data results shows that the radio interference generated by EHV transmission lines have no effect on GNSS receiver internal noise levels and valid GNSS observation rate. Within 50 meters of the EHV transmission lines, the multi-path effects (mp1 and mp2 value) significantly exceeded the normal range and becomes larger with the increase of the voltage .outside 50 meters of the EHV transmission line, the multi-path effects have almost no effect on the high-precision GNSS observations.

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Terrain changes from images acquired on opportunistic flights by SfM photogrammetry

The Cryosphere ◽

10.5194/tc-11-827-2017 ◽

2017 ◽

Vol 11 (2) ◽

pp. 827-840 ◽

Cited By ~ 12

Author(s):

Luc Girod ◽

Christopher Nuth ◽

Andreas Kääb ◽

Bernd Etzelmüller ◽

Jack Kohler

Keyword(s):

Low Cost ◽

Rapid Change ◽

Satellite System ◽

Light Transport ◽

Area Of Interest ◽

Accuracy And Precision ◽

Global Navigation Satellite ◽

The Cost ◽

Gnss Data

Abstract. Acquiring data to analyse change in topography is often a costly endeavour requiring either extensive, potentially risky, fieldwork and/or expensive equipment or commercial data. Bringing the cost down while keeping the precision and accuracy has been a focus in geoscience in recent years. Structure from motion (SfM) photogrammetric techniques are emerging as powerful tools for surveying, with modern algorithm and large computing power allowing for the production of accurate and detailed data from low-cost, informal surveys. The high spatial and temporal resolution permits the monitoring of geomorphological features undergoing relatively rapid change, such as glaciers, moraines, or landslides. We present a method that takes advantage of light-transport flights conducting other missions to opportunistically collect imagery for geomorphological analysis. We test and validate an approach in which we attach a consumer-grade camera and a simple code-based Global Navigation Satellite System (GNSS) receiver to a helicopter to collect data when the flight path covers an area of interest. Our method is based and builds upon Welty et al. (2013), showing the ability to link GNSS data to images without a complex physical or electronic link, even with imprecise camera clocks and irregular time lapses. As a proof of concept, we conducted two test surveys, in September 2014 and 2015, over the glacier Midtre Lovénbreen and its forefield, in northwestern Svalbard. We were able to derive elevation change estimates comparable to in situ mass balance stake measurements. The accuracy and precision of our DEMs allow detection and analysis of a number of processes in the proglacial area, including the presence of thermokarst and the evolution of water channels.

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Validation of the EGSIEM-REPRO GNSS Orbits and Satellite Clock Corrections

Remote Sensing ◽

10.3390/rs12142322 ◽

2020 ◽

Vol 12 (14) ◽

pp. 2322 ◽

Cited By ~ 1

Author(s):

Andreja Sušnik ◽

Andrea Grahsl ◽

Daniel Arnold ◽

Arturo Villiger ◽

Rolf Dach ◽

...

Keyword(s):

Orbit Determination ◽

Precise Orbit Determination ◽

Satellite System ◽

Satellite Orbits ◽

Satellite Clock ◽

Gps Satellites ◽

Glonass Satellite ◽

Global Navigation Satellite ◽

Gravity Recovery ◽

First Time

In the framework of the European Gravity Service for Improved Emergency Management (EGSIEM) project, consistent sets of state-of-the-art reprocessed Global Navigation Satellite System (GNSS) orbits and satellite clock corrections have been generated. The reprocessing campaign includes data starting in 1994 and follows the Center for Orbit Determination in Europe (CODE) processing strategy, in particular exploiting the extended version of the empirical CODE Orbit Model (ECOM). Satellite orbits are provided for Global Positioning System (GPS) satellites since 1994 and for Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS) since 2002. In addition, a consistent set of GPS satellite clock corrections with 30 s sampling has been generated from 2000 and with 5 s sampling from 2003 onwards. For the first time in a reprocessing scheme, GLONASS satellite clock corrections with 30 s sampling from 2008 and 5 s from 2010 onwards were also generated. The benefit with respect to earlier reprocessing series is demonstrated in terms of polar motion coordinates. GNSS satellite clock corrections are validated in terms of completeness, Allan deviation, and precise point positioning (PPP) using terrestrial stations. In addition, the products herein were validated with Gravity Recovery and Climate Experiment (GRACE) precise orbit determination (POD) and Satellite Laser Ranging (SLR). The dataset is publicly available.

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Automatic Mapping of Center Line of Railway Tracks using Global Navigation Satellite System, Inertial Measurement Unit and Laser Scanner

Remote Sensing ◽

10.3390/rs12030411 ◽

2020 ◽

Vol 12 (3) ◽

pp. 411 ◽

Cited By ~ 2

Author(s):

Sangeetha Shankar ◽

Michael Roth ◽

Lucas Andreas Schubert ◽

Judith Anne Verstegen

Keyword(s):

Laser Scanner ◽

Satellite System ◽

Sensor Data ◽

Measurement Unit ◽

Center Line ◽

Railway Tracks ◽

Combination Of Methods ◽

Global Navigation Satellite ◽

Inertial Measurements ◽

Gnss Data

Up-to-date geodatasets on railway infrastructure are valuable resources for the field of transportation. This paper investigates three methods for mapping the center lines of railway tracks using heterogeneous sensor data: (i) conditional selection of satellite navigation (GNSS) data, (ii) a combination of inertial measurements (IMU data) and GNSS data in a Kalman filtering and smoothing framework and (iii) extraction of center lines from laser scanner data. Several combinations of the methods are compared with a focus on mapping in tree-covered areas. The center lines of the railway tracks are extracted by applying these methods to a test dataset collected by a road-rail vehicle. The guard rails in the test area were also extracted during the center line detection process. The combination of methods (i) and (ii) gave the best result for the track on which the measurement vehicle had moved, mapping almost 100% of the track. The combination of methods (ii) and (iii) and the combination of all three methods gave the best result for the other parallel tracks, mapping between 25% and 80%. The mean perpendicular distance of the mapped center lines from the reference data was 1.49 meters.

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Integrated GNSS Attitude and Position Determination based on an Affine Constrained Model

Journal of Navigation ◽

10.1017/s0373463317000522 ◽

2017 ◽

Vol 71 (1) ◽

pp. 134-150

Author(s):

Haiying Liu ◽

Lei Xu ◽

Xiaolin Meng ◽

Xibei Chen ◽

Junyi Li

Keyword(s):

Attitude Determination ◽

Satellite System ◽

Determination Method ◽

Position Determination ◽

Static Data ◽

Constraint Information ◽

Constrained Model ◽

Global Navigation Satellite ◽

Constraint Model ◽

Gnss Data

Global Navigation Satellite System (GNSS) attitude determination and positioning play an important role in many navigation applications. However, the two GNSS-based problems are usually treated separately. This ignores the constraint information of the GNSS antenna array and the accuracy is limited. To improve the performance of navigation, an integrated attitude and position determination method based on an affine constraint model is presented. In the first part, the GNSS array model and affine constrained attitude determination method are compared with the unconstrained methods. Then the integrated attitude and position determination method is presented. The performance of the proposed method is tested with a series of static data and dynamic experimental GNSS data. The results show that the proposed method can improve the success rate of ambiguity resolution to further improve the accuracy of attitude determination and relative positioning compared to the unconstrained methods.

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Subsidence determination in the Central Valley, California

Reports on Geodesy and Geoinformatics ◽

10.2478/rgg-2018-0012 ◽

2018 ◽

Vol 106 (1) ◽

pp. 35-42 ◽

Cited By ~ 1

Author(s):

Marcelo Romero ◽

Mike Mustafa Berber

Keyword(s):

Central Valley ◽

Satellite System ◽

Geodetic Survey ◽

Reference Station ◽

National Geodetic Survey ◽

The North ◽

Elevation Changes ◽

System Data ◽

Global Navigation Satellite ◽

Gnss Data

Abstract Twenty four hour GNSS (Global Navigation Satellite System) data acquired monthly for 5 years from 8 CORS (Continuously Operating Reference Station) stations in Central Valley, California are processed and vertical velocities of the points are determined. To process GNSS data, online GNSS data processing service APPS (Automatic Precise Positioning Service) is used. GNSS data downloaded from NGS (National Geodetic Survey) CORS are analyzed and subsidence at these points is portrayed with graphics. It is revealed that elevation changes range from 5 mm uplift in the north to 163 mm subsidence in the southern part of the valley.

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Extensive Investigation of the Land Subsidence Impressions on Gedebage District, Bandung, Indonesia

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/873/1/012044 ◽

2021 ◽

Vol 873 (1) ◽

pp. 012044

Author(s):

I Gumilar ◽

TP. Sidiq ◽

I Meilano ◽

B Bramanto ◽

G Pambudi

Keyword(s):

Land Subsidence ◽

Urban Areas ◽

Average Rate ◽

Satellite System ◽

Synthetic Aperture ◽

Interferometric Synthetic Aperture Radar ◽

Infrastructure Development ◽

Global Navigation Satellite ◽

Almost All ◽

The Impact

Abstract Gedebage district is presently experiencing rapid and mass infrastructure development and becoming one of the developed districts in Bandung, Indonesia. A football stadium, several luxury housing, the grand mosque of West Java province, and a business center have been built in this district. However, it is well known that the Gedebage district has turned into one of the Bandung districts that suffers from land subsidence phenomena. Since 2000, the Gedebage district has suffered land subsidence at an average rate of 10 cm per year and becoming one of the fastest sinking districts in Bandung. This fast land subsidence phenomenon is suspected of affecting the infrastructure in this district. Therefore, this work aims to capture the current subsidence rate in the Gedebage district using the geodetic approach of the combination of the Global Navigation Satellite System (GNSS) with Interferometric Synthetic Aperture Radar (InSAR) and investigate the impact of land subsidence on infrastructures in Gedebage district. We use GNSS campaign datasets from the years 2016 and 2019. Each GNSS campaign was performed at least 10-12 hours of observations. We also utilize a similar period of 2016 to 2019 for the InSAR datasets. Utilizing both GNSS and InSAR datasets, we can capture the subsidence with the rate reaching 4 -15 cm per year between 2016 and 2019, and it occurs uniformly in this district. The impact of land subsidence occurred in almost all urban areas in the Gedebage district. These impacts include cracks in buildings, bridges and roads, and also tilted buildings.

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Fusion of GNSS and Satellite Radar Interferometry: Determination of 3D Fine-Scale Map of Present-Day Surface Displacements in Italy as Expressions of Geodynamic Processes

Remote Sensing ◽

10.3390/rs11040394 ◽

2019 ◽

Vol 11 (4) ◽

pp. 394 ◽

Cited By ~ 5

Author(s):

Gregorio Farolfi ◽

Aldo Piombino ◽

Filippo Catani

Keyword(s):

Surface Deformation ◽

Satellite System ◽

Sar Interferometry ◽

Ground Movement ◽

Sight Loss ◽

Geodynamic Processes ◽

Ground Point ◽

Space Geodetic Techniques ◽

Satellite Radar ◽

Global Navigation Satellite

We present a detailed map of ground movement in Italy derived from the combination of the Global Navigation Satellite System (GNSS) and Satellite Synthetic Aperture Radar (SAR) interferometry. These techniques are two of the most used space geodetic techniques to study Earth surface deformation. The above techniques provide displacements with respect to different components of the ground point position; GNSSs use the geocentric International Terrestrial Reference System 1989 (ITRS89), whereas the satellite SAR interferometry components are identified by the Lines of Sight (LOSs) between a satellite and ground points. Moreover, SAR interferometry is a differential technique, and for that reason, displacements have no absolute reference datum. We performed datum alignment of InSAR products using precise velocity fields derived from GNSS permanent stations. The result is a coherent ground velocity field with detailed boundaries of velocity patterns that provide new information about the complex geodynamics involved on the Italian peninsula and about local movements.

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An improved pixel-based water vapor tomography model

Annales Geophysicae ◽

10.5194/angeo-37-89-2019 ◽

2019 ◽

Vol 37 (1) ◽

pp. 89-100

Author(s):

Yibin Yao ◽

Linyang Xin ◽

Qingzhi Zhao

Keyword(s):

Water Vapor ◽

Three Dimensional ◽

Satellite System ◽

Reference Station ◽

Weather Forecasts ◽

Satellite Positioning ◽

Optimal Polynomial ◽

Improved Model ◽

Global Navigation Satellite ◽

Gnss Data

Abstract. As an innovative use of Global Navigation Satellite System (GNSS), the GNSS water vapor tomography technique shows great potential in monitoring three-dimensional water vapor variation. Most of the previous studies employ the pixel-based method, i.e., dividing the troposphere space into finite voxels and considering water vapor in each voxel as constant. However, this method cannot reflect the variations in voxels and breaks the continuity of the troposphere. Moreover, in the pixel-based method, each voxel needs a parameter to represent the water vapor density, which means that huge numbers of parameters are needed to represent the water vapor field when the interested area is large and/or the expected resolution is high. In order to overcome the abovementioned problems, in this study, we propose an improved pixel-based water vapor tomography model, which uses layered optimal polynomial functions obtained from the European Centre for Medium-Range Weather Forecasts (ECMWF) by adaptive training for water vapor retrieval. Tomography experiments were carried out using the GNSS data collected from the Hong Kong Satellite Positioning Reference Station Network (SatRef) from 25 March to 25 April 2014 under different scenarios. The tomographic results are compared to the ECMWF data and validated by the radiosonde. Results show that the new model outperforms the traditional one by reducing the root-mean-square error (RMSE), and this improvement is more pronounced, at 5.88 % in voxels without the penetration of GNSS rays. The improved model also has advantages in more convenient expression.

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