Impact of sand and dust storms on tropospheric parameter estimation by GPS.

The transport of dust from the Middle East and African deserts affects European and Asian countries at certain times of the year, especially in spring. Turkey is one of these countries, and many dust storm events have occurred in the first half of 2022, which have affected especially the southeastern part of Anatolia. Apart from threatening human health, dust and sand particles, which are described as particulate matter, may possibly affect Global Positioning System (GPS) signals. The purpose of this research is to look into the effects of particulate matter less than 10 μm (PM10) on GPS-estimated precipitable water vapor (PWV). Hourly PM10 and PWV data between April 1, 2022, and June 10, 2022, were utilized. Four different extreme dust concentration events and a benchmark period were investigated separately. Hourly data results showed that correlation coefficients vary according to events, wind directions, and the distance between GPS stations and air quality monitoring stations. Also, other meteorological parameters that affect PWV, such as temperature, relative humidity, and pressure, were investigated and found to have no anomalies that could affect PWV. Hourly and daily correlation coefficients in the benchmark period were significantly lower compared to dusty days, which indicates that there is no real correlation between PM10 and PWV concentrations in clear air conditions. Only with the increase of PM10 to extreme levels does the relationship show itself. Therefore, this study suggests that for all GPS applications, such as positioning or PWV estimation, PM10 concentrations should be considered.