Combining Meteosat-10 satellite image data with GPS tropospheric path delays to estimate regional integrated water vapor (IWV) distribution

Abstract

Abstract. Using GPS satellites signals, we can study different processes and coupling mechanisms that can help us understand the physical conditions in the lower atmosphere, which might lead or act as proxies for severe weather events such as extreme storms and flooding. GPS signals received by ground stations are multi-purpose and can also provide estimates of tropospheric zenith delays, which can be converted into accurate integrated water vapor (IWV) observations using collocated pressure and temperature measurements on the ground. Here, we present for the first time the use of Israel's dense regional GPS network for extracting tropospheric zenith path delays combined with near-realtime Meteosat-10 water vapor (WV) and surface temperature pixel intensity values (7.3 and 10.8 µm channels, respectively) in order to assess whether it is possible to obtain absolute IWV (kg m −2 ) distribution. The results show good agreement between the absolute values obtained from our triangulation strategy based solely on GPS zenith total delays (ZTD) and Meteosat-10 surface temperature data compared with available radiosonde IWV absolute values. The presented strategy can provide high temporal and special IWV resolution, which is needed as part of the accurate and comprehensive observation data integrated in modern data assimilation systems and is required for increasing the accuracy of regional numerical weather prediction systems forecast.

On the Potential of Improving WRF Model Forecasts by Assimilation of High-Resolution GPS-Derived Water-Vapor Maps Augmented with METEOSAT-11 Data

“…For the present study, we used the data obtained from the Israeli GPS network (SOI-APN) that includes more than 20 stations, covering the entire Israeli area [31,32]. These geodetic GPS stations record raw data in RINEX format.…”

“…Estimation of WV amount in the troposphere using remote sensing measurements from satellites such as the METEOSAT series is useful for producing proper 2D IWV distribution maps [28][29][30]. Recently, Leontiev and Reuveni [31,32] developed a technique for augmenting IWV estimations using both remote sensing measurements from satellites such as METEOSAT and GNSS tropospheric path delays. The suggested strategy is based first on estimating METEOSAT 7.3 µm WV pixel values by extracting the mathematical dependency between the IWV amount extracted from GPS ZWD and the METEOSAT-10 data.…”

“…This method increases the accuracy of the IWV regional map estimations being verified against in situ radiosonde measurements, and assists to acquire the absolute amount of water in the atmosphere, both in the form of clouds and vapor. The application of this method reduced the mean error (ME) and root mean square (RMSE) differences between the GPS-IWV estimations and the radiosonde measurements from 1.77 and 2.81 kg/m 2 to 0.74 and 2.04 kg/m 2 , respectively [31,32]. Here, we investigate the potential of improving WRF model forecasts by assimilation of high-resolution 2D IWV distribution maps derived from GPS tropospheric path delay augmented by METEOSAT-11 WV imagery data, based on the survey of Israel-active per manent network (SOI-APN) with more than 20 GPS geodetic stations over the entire coun try (Figure 1).…”

GPS signal derived precipitable water vapor and its applications in rainfall prediction

“…(2.9) to derive the ZHD values [1,[74][75][76]. VMF1 models are also used in deriving the hydrostatic delays [76,77]. Along with the VMF1 mapping coefficients, the VMF1 hydrostatic delays are provided in the GGOS website [68].…”

“…Therefore, the choice of the software might be determined by the ease of its availability and the constellation(s) (GPS, GLONASS, BeiDou, Gallelio) that it is applicable for. In this thesis, we use GIPSY software version 6.4 by JPL, which is being used by many researchers in this field [77,[84][85][86] as it is easily available and is free for educational purposes, it is well documented and it is suitable for GPS constellation which has more than 500 ground receivers all around the globe.…”