Measuring the height of snow cover using GNSS reflectometry

Abstract

Height of the snow cover is an important parameter used to predict crop yields and floods. The traditional method of measuring the height of the snow cover according to the readings of three snow gauges has the disadvantage that in open areas the snow cover is blown out and redistributed under the influence of the wind. The new method of GNSS reflectometry makes it possible to circumvent this disadvantage by averaging the height of the snow cover over a certain local area around the antenna of the ground-based GNSS radio signal receiver. The aim of the study is to assess the accuracy of determining the height of the snow cover using GNSS reflectometry using the example of the IRKM station (Irkutsk city) for the winter period 2021/2022. It has been established that the standard deviation of heights of the snow cover determined by reflectometry of GPS and GLONASS radio signals from heights of the snow cover recorded by the traditional method at a meteorological station was 3,2 cm. The standard deviation of heights of snow cover obtained from the results of processing only GLONASS radio signals was 5,6 cm. At the same time, for the GLONASS system, the dependence of the discrepancies with the reference data on the height of the snow cover is obvious: the greater the depth of the snow cover, the smaller the discrepancies. Thus, the standard deviation of discrepancies, calculated under conditions of the height of the snow cover above 10 cm, is only 3,0 cm. Thus, it can be preliminarily concluded that the GNSS refletometry method is able to supplement the traditional method of measuring the height of the snow cover.