Abstract
Water vapor is one of the important atmospheric components of atmospheric circulation and dynamics, and its accurate and spatiotemporally continuous estimation is important for understanding the water vapor conveying mechanism and the hydrologic cycle. We proposed a new fusion strategy where the precipitable water vapor (PWV) derived from global positioning system (GPS) and surface meteorological observations was introduced. Compared to previous methods using radiosonde data, remote sensing satellite water vapor products, and atmospheric reanalysis products, our fusion strategy adopted the PWV calculated from the surface meteorological observations for the first time. It also has a potential near real-time capability for high temporal resolution water vapor monitoring in areas with sparse GPS station distribution (the average distance exceeds 100 km) such as mountainous areas, basins, and plateaus. Based on PWV data derived from 35 GPS and 237 surface meteorological stations, we established hourly fusion models through simplified spherical cap harmonic analysis for the Loess Plateau of China. The validation results show that when PWV data derived from ERA5 reanalysis and radiosonde in 2020 were used as reference values, the mean root-mean-square (RMS) of the PWV derived from fusion models based on GPS and surface meteorological observations were 3.87 and 2.51 mm, respectively. Compared to the strategy using only GPS observations, the accuracy of the model PWV was improved by approximately 60.4% by fusing GPS and surface meteorological PWV data when the ERA5 data is used as a references value. Compared to the strategy using only surface meteorological observations, the accuracy of the model PWV was respectively improved by approximately 16.0% and 32.7% after fusing GPS-derived PWV data when the ERA5 and radiosonde data are used as reference values. Therefore, through our fusion strategy, the accuracy of GPS PWV data and the spatial resolution of surface meteorological PWV data could be complementary in regard to water vapor field estimation. This study shows that the fusion strategy has a potential application prospect in near real-time water vapor monitoring for numerical weather predictions (NWP) data assimilation and short-term rainfall forecasting.
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Data availability
Radiosonde data before and after 2020 in China employed in this work are provided by the University of Wyoming at http://weather.uwyo.edu/upperair/sounding.html and http://weather.uwyo.edu/upperair/bufrraob.shtml, respectively. The CMONOC ZTD products are provided by the China Earthquake Administration at http://www.cgps.ac.cn. ERA5 reanalysis data are provided by ECMWF at https://cds.climate.copernicus.eu/cdsapp#!/dataset/reanalysis-era5-pressure-levels?tab=overview. The surface meteorological observations are provided by China Meteorological Data Service Center at http://data.cma.cn/.
References
Albergel C, Dutra E, Munier S, Calvet J-C, Munoz-Sabater J, de Rosnay P, Balsamo G (2018) ERA-5 and ERA-Interim driven ISBA land surface model simulations: Which one performs better? Hydrol Earth Syst Sci 22(6):3515–3532
Alshawaf F, Hinz S, Mayer M, Meyer FJ (2015) Constructing accurate maps of atmospheric water vapor by combining interferometric synthetic aperture radar and GNSS observations. J Geophys Res Atmos 120(4):1391–1403
Aragón Paz JM, Mendoza LPO, Fernández LI (2023) Near-real-time GNSS tropospheric IWV monitoring system for South America. GPS Solut 27(2):1–23
Barindelli S, Realini E, Venuti G, Fermi A, Gatti A (2018) Detection of water vapor time variations associated with heavy rain in northern Italy by geodetic and low-cost GNSS receivers. Earth Planets Space 70:1–18
Bevis M, Businger S, Herring TA, Rocken C, Anthes RA, Ware RH (1992) GPS meteorology: remote sensing of atmospheric water vapor using the global positioning system. J Geophys Res Atmos 97(D14):15787–15801
Biswas AN, Lee YH, Manandhar S (2022) Rainfall forecasting using GPS-derived atmospheric gradient and residual for tropical region. IEEE Trans Geosci Remote Sens 60:1–10
Bolton D (1980) The computation of equivalent potential temperature. Mon Weather Rev 108(7):1046–1053
Bosy J, Rohm W, Borkowski A, Kroszczynski K, Figurski M (2010) Integration and verification of meteorological observations and NWP model data for the local GNSS tomography. Atmos Res 96(4):522–530
De Santis A, Torta J (1997) Spherical cap harmonic analysis: a comment on its proper use for local gravity field representation. J Geodesy 71(9):526–532
Duan JP et al (1996) GPS meteorology: Direct estimation of the absolute value of precipitable water. J Appl Meteorol 35(6):830–838
Edwards TH, Stoll S (2018) Optimal Tikhonov regularization for DEER spectroscopy. J Magn Reson 288:58–68
Fu B, Wang S, Liu Y, Liu J, Liang W, Miao C (2017) Hydrogeomorphic ecosystem responses to natural and anthropogenic changes in the Loess Plateau of China. Annu Rev Earth Planet Sci 45:223–243
Gutman SI, Sahm SR, Benjamin SG, Schwartz BE, Holub KL, Stewart JQ, Smith TL (2004) Rapid retrieval and assimilation of ground based GPS precipitable water observations at the NOAA forecast systems laboratory: Impact on weather forecasts. J Meteorol Soc Jpn 82(1B):351–360
He C, Wu S, Wang X, Hu A, Wang Q, Zhang K (2017) A new voxel-based model for the determination of atmospheric weighted mean temperature in GPS atmospheric sounding. Atmos Meas Tech 10(6):2045–2060
Hurvich CM, Tsai CL (1989) Regression and time series model selection in small samples. Biometrika 76(2):297–307
Karabatić A, Weber R, Haiden T (2011) Near real-time estimation of tropospheric water vapour content from ground based GNSS data and its potential contribution to weather now-casting in Austria. Adv Space Res 47(10):1691–1703
Koch KR, Kusche J (2002) Regularization of geopotential determination from satellite data by variance components. J Geodesy 76(5):259–268
Leckner B (1978) The spectral distribution of solar radiation at the earth’s surface—elements of a model. Sol Energy 20(2):143–150
Li X, Long D (2020) An improvement in accuracy and spatiotemporal continuity of the MODIS precipitable water vapor product based on a data fusion approach. Remote Sens Environ 248:111966
Li H et al (2020) Development of an improved model for prediction of short-term heavy precipitation based on GNSS-derived PWV. Remote Sens 12(24):4101
Li Z (2004) Production of regional 1 km× 1 km water vapor fields through the integration of GPS and MODIS Data. In: Proc. ION GNSS 2004, Institute of Navigation, Long Beach, CA, September 21–24, 2396–2403
Liu J, Chen R, Wang Z, Zhang H (2011) Spherical cap harmonic model for mapping and predicting regional TEC. GPS Solut 15(2):109–119
Liu T, Zhang B, Yuan Y, Li M (2018) Real-Time Precise Point Positioning (RTPPP) with raw observations and its application in real-time regional ionospheric VTEC modeling. J Geodesy 92(11):1267–1283
Manandhar S, Lee YH, Meng YS (2019) GPS-PWV based improved long-term rainfall prediction algorithm for tropical regions. Remote Sens 11(22):2643
Offiler D, Jones J, Bennit G, Vedel H (2010) EIG EUMETNET GNSS Water Vapour Programme (E-GVAP-II). Product Requirements Document, MetOffice
Rohm W, Guzikowski J, Wilgan K, Kryza M (2019) 4DVAR assimilation of GNSS zenith path delays and precipitable water into a numerical weather prediction model WRF. Atmos Measur Tech 12(1):345–361
Ross RJ, Elliott WP (1996) Tropospheric water vapor climatology and trends over North America: 1973–93. J Clim 9(12):3561–3574
Sapucci LF, Machado LA, de Souza EM, Campos TB (2019) Global positioning system precipitable water vapour (GPS-PWV) jumps before intense rain events: a potential application to nowcasting. Meteorol Appl 26(1):49–63
Shi H, Shao M (2000) Soil and water loss from the Loess Plateau in China. J Arid Environ 45(1):9–20
Shi JB, Xu CQ, Guo JM, Gao Y (2015) Real-time GPS precise point positioning-based precipitable water vapor estimation for rainfall monitoring and forecasting. IEEE Trans Geosci Remote Sens 53(6):3452–3459
Sugiura N (1978) Further analysis of the data by Akaike’s information criterion and the finite corrections. Commun Stat Part A-Theory Methods 7(1):13–26
Thayer GD (1974) An improved equation for the radio refractive index of air. Radio Sci 9(10):803–807
Tikhonov AN, Arsenin VJ, Arsenin VIA, Arsenin VY (1977) Solutions of ill-posed problems. Wiley, New York
Tomassini M, Gendt G, Dick G, Ramatschi M, Schraff C (2002) Monitoring of Integrated Water Vapour from ground-based GPS observations and their assimilation in a limited-area NWP model. Phys Chem Earth 27(4–5):341–346
Wang X, Zhang K, Wu S, Fan S, Cheng Y (2016) Water vapor-weighted mean temperature and its impact on the determination of precipitable water vapor and its linear trend. J Geophys Res Atmos 121(2):833–852
Wang X, Zhang K, Wu S, He C, Cheng Y, Li X (2017) Determination of zenith hydrostatic delay and its impact on GNSS-derived integrated water vapor. Atmos Meas Tech 10(8):2807–2820
Wilgan K, Rohm W, Bosy J (2015) Multi-observation meteorological and GNSS data comparison with numerical weather prediction model. Atmos Res 156:29–42
Yang J, Qiu J (1996) The empirical expressions of the relation between precipitable water and ground water vapor pressure for some areas in China. Chin J Atmos Sci 20(5):620
Yang Q, Wei W, Li J (2008) Temporal and spatial variation of atmospheric water vapor in the Taklimakan Desert and its surrounding areas. Chin Sci Bull 53(Suppl 2):71–78
Yao Y, Hu Y, Yu C, Zhang B, Guo J (2016) An improved global zenith tropospheric delay model GZTD2 considering diurnal variations. Nonlinear Process Geophys 23(3):127–136
Yao Y, Xu X, Hu Y (2018) Establishment of a regional precipitable water vapor model based on the combination of GNSS and ECMWF data. Atmos Meas Tech Discuss, pp 1–21
Zhang B, Yao Y (2021) Precipitable water vapor fusion based on a generalized regression neural network. J Geodesy 95(3):1–14
Zhang B, Yao Y, Xin L, Xu X (2019) Precipitable water vapor fusion: An approach based on spherical cap harmonic analysis and Helmert variance component estimation. J Geodesy 93(12):2605–2620
Zhao QZ, Yao YB, Yao WQ (2018) GPS-based PWV for precipitation forecasting and its application to a typhoon event. J Atmos Solar Terr Phys 167:124–133
Zhao Q, Du Z, Li Z, Yao W, Yao Y (2021) Two-step precipitable water vapor fusion method. IEEE Trans Geosci Remote Sens 60:1–10
Zonghu Z (1991) Soil erosion processes in the Loess Plateau of Northwestern China. GeoJ 24(2):195–200
Acknowledgements
This work was supported by the Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications (Grant No. NY221141) and the National Natural Science Foundation of China (Grant No. 42304027 and 41974026). We thank the ECMWF, University of Wyoming and IGRA, China Earthquake Administration, and China Meteorological Data Service Center for providing the ERA5 reanalysis data, radiosonde data, ZTD products, and hourly meteorological observations, respectively.
Funding
Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications (Grant No.: NY221141); National Natural Science Foundation of China (Grant Nos.: 42304027, 41974026).
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Yang, L., Li, Z., Tian, Y. et al. Estimation of the water vapor field by fusing GPS and surface meteorological observations on the Loess Plateau of China. GPS Solut 28, 55 (2024). https://doi.org/10.1007/s10291-023-01599-y
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DOI: https://doi.org/10.1007/s10291-023-01599-y