Application of GNSS Reflectometry in Water Level Monitoring using Low-cost GNSS Antenna: A Case Study in Tam Giang Lagoon, Thua Thien Hue Province
Main Article Content
Abstract
Extreme hydrological events become increasingly unpredictable due to climate change and sea-level rise, highlighting the importance of coastal sea level monitoring. This study aims to develop a Global Navigation Satellite System (GNSS) reflectometry technology that uses low-cost multi-frequency antennas to measure water levels. A multi-frequency GNSS antenna was
installed in the Tam Giang lagoon area, Thua Thien Hue province, to collect data of GPS/GLONASS/Galileo/Beidou satellites at 1Hz from April 10 to April 29, 2022. Water level elevation is calculated from GNSS reflectometry data using Interference Pattern Technical (IPT) based on Signal-to-Noise Ratio (SNR). After filtering, the water level results are validated by data from the water level sensor located in the same location. The Root Mean Square Error between the water level from the GNSS - Reflectometry (GNSS– R) and the in situ measurement is 0,049 m and the correlation coefficient reaches 0,93 when combining different frequencies. The study results demonstrate that the multi-frequency GNSS-R station can be used as an additional method to measure water levels with an accuracy comparable to that of a standard tidal gauge. In addition, the study results also show the sensitivity of the GNSS reflected signal to weather conditions and the state of the sea surface, which is the basis for forecasting and early warning of storm surge extremes from GNSS reflectometry data.
Keywords:
Keywords: GNSS-R, IPT, Tam Giang lagoon, water level.
References
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F. G. Nievinski, Raytracing Atmospheric Delays iIn Ground-Based GNSS Reflectometry, Journal of Geodesy, Vol. 94, 2020, pp. 1-12, https://doi.org/10.1007/s00190-020-01390-8.
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[39] J. S. Löfgren, R. Haas, H. Scherneck, M. S. Bos, Three Months of Local Sea Level Derived from Reflected Gnss Signals, Radio Science, Vol. 46, No. 6, 2011, pp. 1-12, https://doi.org/10.1029/2011RS004693.
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[41] N. Roussel, Application De La Réflectométrie GNSS À L’étude Des Redistributions Des Masses D’eau À La Surface De La Terre, Univérsité Paul Sabatier Toulouse III, 2015b, https://tel.archives-ouvertes.fr/tel-01417284 (accessed on: May 10st, 2022).
[42] K. M. Larson et al., Use of GPS Receivers As A Soil Moisture Network For Water Cycle Studies Geophysical Research Letters, Vol. 35, No. 24, 2008b, https://doi.org/10.1029/2008GL036013.
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[45] A. Rius, E. Cardellach, M. M. Neira, Altimetric Analysis of the Sea-Surface GPS-Reflected Signals, IEEE Transactions on Geoscience and Remote Sensing, Vol. 8, No. 4, 2010, pp. 2119-2127, https://doi.org/10.1109/TGRS.2009.2036721.
[2] N. Chen et al., Hurricane Sandy Storm Surges Observed by HY-2A Satellite Altimetry and Tide Gauges Journal of Geophysical Research: Oceans, Vol. 119, No. 7, 2014, pp. 4542-4548, https://doi.org/10.1002/2013JC009782.
[3] S. Fardin et al., Assessment of the Accuracy of Recent Empirical and Assimilated Tidal Models for the Great Barrier Reef, Australia, Using Satellite and Coastal Data Remote Sensing,
Vol. 11, 2019, https://doi.org/10.3390/rs11101211.
[4] J. C. M. Dullaart et al., Advancing Global Storm Surge Modelling Using the New ERA5 Climate Reanalysis, Climate Dynamics, Vol. 54, 2020,
pp. 1007-1021,
https://doi.org/10.1007/s00382-019-05044-0.
[5] B. M. Míguez, B. P. Gómez, E. A. Fanjul, The ESEAS-RI Sea Level Test Station: Reliability and Accuracy of Different Tide Gauges The International Hydrographic Review, Vol. 6, No. 1, 2005, pp. 44-53.
[6] S. Pytharouli, S. Chaikalis, S. C. Stiros, Uncertainty and Bias in Electronic Tide-Gauge Records: Evidence from Collocated Sensors Measurement, Vol. 125, 2018, pp. 496-508, https://doi.org/10.1016/j.measurement.2018.05.012.
[7] F. Frappart et al., Evaluation of the Performances of Radar and Lidar Altimetry Missions for Water Level Retrievals in Mountainous Environment: The Case of the Swiss Lakes Remote Sensing,
Vol. 13, No. 11, 2021, https://doi.org/10.3390/rs13112196.
[8] F. Frappart et al., Principles and Applications in Earth Sciences in Satellite Altimetry, In Wiley Encyclopedia of Electrical and Electronics Engineering; Publisher: John Wiley & Sons, Inc., 2017, https://doi.org/10.1002/047134608X.W1125.pub2.
[9] S. Biancamaria et al., Satellite Radar Altimetry Water Elevations Performance Over A Hundred Meter Wide River: Evaluation Over the Garonne River" Advances in Space Research, Vol. 1, No. 1, 2017, pp. 128-146, https://doi.org/10.1016/j.asr.2016.10.008.
[10] K. M. Larson et al., Dynamic Sea Level Variation from GNSS: 2020 Shumagin Earthquake Tsunami Resonance and Hurricane Laura Geophysical Research Letters, Vol. 48, No. 4, 2020, https://doi.org/10.1029/2020GL091378.
[11] N. Roussel et al., Sea Level Monitoring And Sea State Estimate Using A Single Geodetic Receiver Remote Sensing of Environment, 2015, pp. 261-277, https://doi.org/10.1016/j.rse.2015.10.011.
[12] K. M. Larson et al., Coastal Sea Level Measurements Using A Single Geodetic GPS Receiver Advances in Space Research, Vol. 51, 2013, pp. 1301-1310, https://doi.org/10.1016/j.asr.2012.04.017.
[13] J. Zhongshan et al., Characterizing Spatiotemporal Patterns of Terrestrial Water Storage Variations Using GNSS Vertical Data in Sichuan, China Journal of Geophysical Research: Solid Earth,
Vol. 126, No. 12, 2021, https://doi.org/10.1029/2021JB022398.
[14] J. Zhongshan et al., Monitoring Time-Varying Terrestrial Water Storage Changes Using Daily GNSS Measurements in Yunnan, Southwest China Remote Sensing of Environment, Vol. 254, 2021, https://doi.org/10.1016/j.rse.2020.112249.
[15] J. Shuanggen, Q. Xiaodong, K. Hakan, Snow Depth Variations Estimated from GPS-Reflectometry: A Case Study in Alaska from L2P SNR Data Remote Sensing, Vol. 8, No. 1, 2016, https://doi.org/10.3390/rs8010063.
[16] C. Chew, E. E. Small, K. M. Larson, An Algorithm for Soil Moisture Estimation Using GPS-Interferometric Reflectometry for Bare and Vegetated Soil, GPS Soluttions, Vol. 20, No. 3, 2015, https://doi.org/10.1007/s10291-015-0462-4.
[17] K. M. Larson et al., GPS Multipath and Its Relation to Near Surface Soil Moisture Content, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, Vol. 3, No. 1, 2010, pp. 91-99, https://doi.org/10.1109/JSTARS.2009.2033612.
[18] V. P. Lan et al., Identifying 2010 Xynthia Storm Signature in GNSS-R-Based Tide Records, Remote Sensing, Vol. 11, No. 7, 2019, https://doi.org/10.3390/rs11070782.
[19] J. Park, S. K. Kim, Monitoring a Storm Surge During Hurricane Harvey Using Multi-Constellation GNSS-Reflectometry, GPS Solutions, Vol. 25, 2021, https://doi.org/10.1007/s10291-021-01105-2.
[20] W. Wan, K. M. Larson, E. E. Small, C. C. Chew,
J. J. Braun, Using Geodetic GPS Receivers to Measure Vegetation Water Content GPS Soluttions, Vol. 19, 2015, pp. 237-248, https://doi.org/10.1007/s10291-014-0383-7.
[21] M. M. Neira et al., The P ARIS Concept: An Experimental Demonstration of Sea Surface Altimetry Using GPS Reflected Signals, IEEE Transactions on Geoscience and Remote Sensing, Vol. 39, 2001, pp. 142-150, https://doi.org/10.1109/36.898676.
[22] S.T. Lowe at el,. 5-cm-Precision Aircraft Ocean Altimetry Using GPS Reflections Geophysical Research Letters, Vol. 29, 2002, pp. 131-134, https://doi.org/10.1029/2002GL014759.
[23] S. Tabibi et al., SNR-Based GNSS-R for Coastal Sea-Level Altimetry, Geosciences, Vol. 11, 2021, https://doi.org/10.3390/geosciences11090391.
[24] H. M. Cuong et al., GNSS-R for Detection of Extreme Hydrological Events, 20th EGU General Assembly, Proceedings from the Conference Held, 2018, pp. 16912.
[25] X. Wang et al., A Correction Method of Height Variation Error Based on One SNR Arc Applied in GNSS–IR Sea-Level Retrieval Remote Sensing, Vol. 14, 2021, https://doi.org/10.3390/rs14010011.
[26] S. Tabibi, F. G. Nievinski, O. Francis, T. V. Dam, Tidal Analysis of GNSS Reflectometry Applied For Coastal Sea Level Sensing in Antarctica and Greenland Remote Sensing of Environment,
Vol. 248, 2020, https://doi.org/10.1016/j.rse.2020.111959.
[27] D. Purnell et al., Quantifying the Uncertainty in Ground-Based GNSSReflectometry Sea Level Measurements, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, Vol. 13, 2020, pp. 4419-4428, https://doi.org/10.1109/JSTARS.2020.3010413.
[28] J. Strandberg, R. Haas, Can We Measure Sea Level With a Tablet Computer?, IEEE Geoscience and Remote Sensing Letters, Vol. 17, 2019, https://doi.org/10.1109/LGRS.2019.2957545.
[29] M. Fagundes et al., An Open-Source Low-Cost Sensor for SNR-Based GNSS Reflectometry: Design and Long-Term Validation Towards Sea-Level Altimetry, GPS Solutions, Vol. 25, 2021, https://doi.org/10.1007/s10291-021-01087-1.
[30] S. D. P. Williams, P. S. Bell, D. L. M. Cann,
R. Cooke, C. Sams, Demonstrating the Potential of Low-Cost GPS Units for the Remote Measurement of Tides and Water Levels Using Interferometric Reflectometry, Journal of Atmospheric and Oceanic Technol, Vol. 27, 2020, pp. 1925-1935, https://doi.org/10.1175/JTECH-D-20-0063.1.
[31] A. S. Gómez, C. Watson, Remote Leveling of Tide Gauges Using GNSS Reflectometry: Case Study at Spring Bay, Australia, GPS Solutions, Vol. 21, 2017, pp. 451-459, 2017, https://doi.org/10.1007/s10291-016-0537-x.
[32] S. D. P. Williams, F. G. Nievinski, Tropospheric Delays in Ground-Based GNSS Multipath Reflectometry - Experimental Evidence From Coastal Sites Journal of Geophysical Research: Solid Earth, Vol. 122, 2017, https://doi.org/10.1002/2016JB013612.
[33] T. Nikolaidou, M. C., Santos, S. D. P. Williams,
F. G. Nievinski, Raytracing Atmospheric Delays iIn Ground-Based GNSS Reflectometry, Journal of Geodesy, Vol. 94, 2020, pp. 1-12, https://doi.org/10.1007/s00190-020-01390-8.
[34] J. Beckheinrich et al., Water Level Monitoring of the Mekong Delta Using GNSS Reflectometry Technique, IEEE Geoscience and Remote Sensing Symposium., 2014, https://doi.org/10.1109/IGARSS.2014.6947311.
[35] Thua Thien Hue Portal, General Characteristics of The Tam Giang – Cau Hai Lagoon System, https://thuathienhue.gov.vn/vi-vn/Thong-tin-du-dia-chi/tid/, 2022 (accessed on: May 10st, 2022).
[36] P. Georgiadou, A. Kleusberg, on Carrier Signal Multipath Effects in Relative Gps Positioning Manuscripta Geodaetica, Vol. 13, No. 3, 1988,
pp. 172-179.
[37] P. W. Ward et al., Understanding GPS: Principles and Applications in Satellite Signal Acquisition Tracking and Data Demodulation, Artech House, 2005, pp. 153-243.
[38] A. Bilich, K. M. Larson, Mapping the GPS Multipath Environment Using the SNR Radio Science, Vol. 42, No. 6, 2007, https://doi.org/10.1029/2007RS003652.
[39] J. S. Löfgren, R. Haas, H. Scherneck, M. S. Bos, Three Months of Local Sea Level Derived from Reflected Gnss Signals, Radio Science, Vol. 46, No. 6, 2011, pp. 1-12, https://doi.org/10.1029/2011RS004693.
[40] K. M. Larson et al., Using GPS Multipath to Measure Soil Moisture Fluctuations: Initial Results GPS Solutions, Vol. 12, No. 3, 2008, pp. 173-177, https://doi.org/10.1007/s10291-007-0076-6.
[41] N. Roussel, Application De La Réflectométrie GNSS À L’étude Des Redistributions Des Masses D’eau À La Surface De La Terre, Univérsité Paul Sabatier Toulouse III, 2015b, https://tel.archives-ouvertes.fr/tel-01417284 (accessed on: May 10st, 2022).
[42] K. M. Larson et al., Use of GPS Receivers As A Soil Moisture Network For Water Cycle Studies Geophysical Research Letters, Vol. 35, No. 24, 2008b, https://doi.org/10.1029/2008GL036013.
[43] N. R. Lomb, Least-Squares Frequency Analysis of Unequally Spaced Data, Astrophysics and Space Science, Vol. 39, No. 2, 1976, pp. 447-462, https://doi.org/10.1007/BF00648343.
[44] J. D. Scargle, Studies In Astronomical Time Series Analysis, II Statistical Aspects of Spectral Analysis of Unevenly Spaced Data, Astrophysical Journal, Vol. 263, 1982, pp. 835-853, https://doi.org/10.1086/160554.
[45] A. Rius, E. Cardellach, M. M. Neira, Altimetric Analysis of the Sea-Surface GPS-Reflected Signals, IEEE Transactions on Geoscience and Remote Sensing, Vol. 8, No. 4, 2010, pp. 2119-2127, https://doi.org/10.1109/TGRS.2009.2036721.