zenith tropospheric delay

Analysis of seasonal changes of zenith tropospheric delay components determined by the radio sounding and GNSS measurements data

The aim of the work is to analyze the change of hydrostatic and wet component values of zenith tropospheric delay (ZTD), determined for all seasons of the year. For today, ZTD components are determined mainly as follows: hydrostatic component – by using one of existing analytical models, mostly Saastamoinen model, and wet component – from GNSS measurements using simulated value of hydrostatic component. Also, in this study we evaluated the accuracy of the obtained values of hydrostatic and wet ZTD components for similar components, determined by radio sounding.

Accuracy estimation of the components of zenith tropospheric delay determined by the radio sounding data and by the GNSS measurements at Praha-libus and GOPE stations

The aim of this work is to evaluate the accuracy of determining the wet component of zenith tropospheric delay (ZTD) from GNSS-measurements and the accuracy of determining the hydrostatic component according to the Saastamoinen model in comparison with the radio sounding data as well. Zenith tropospheric delay is determined mainly by two methods - traditional, using radio sounding or using atmospheric models, such as the Saastamoinen model, and the method of GNSS measurements.

Monitoring of water vapor content by radio sounding data at the Kyiv aerological station and by GNSS observation data at the GLSV station

The purpose of this paper is determining the water vapor content calculated by the wet component of zenith tropospheric delay (ZTD) obtained by means of radio sounding data and GNSS observations. The investigation methodology is the following: the wet component of ZTD is defined as the difference between the total ZTD derived from GNSS measurements and the calculated hydrostatic component. Then the integrated and precipitable water vapor (PWV) is calculated by means of the wet component.

Comparison of the wet component of zenith tropospheric delay derived from GNSS observations with corresponding value from radio soundings

The purpose of this paper is to evaluate an accuracy of the wet component of zenith tropospheric delay obtained by the data of six GNSS stations in comparison with radio sounding data. The determination of hydrostatic and wet components of zenith tropospheric delay was divided into several stages. In the first phase, with an appropriate site for data center processing GNNS-measurements averaged values of zenith tropospheric delay were selected.

Modern approaches to the determination of tropospheric delay and its components

The paper illuminates the following questions according to the determination tropospheric delay: by the data of atmosphere radio sounding, by the data of the basic surface meteorological parameters only and by the data derived from  GNSS observations. Comparison of the results and estimation of accuracy have been carried out.

 

Monitoring of the tropospheric water vapor in the western cross-border zone of Ukraine

Aim. Identifying of reliable estimates of zenith tropospheric delay (ZTD) by the data of GNSS observations (remote monitoring of the troposphere) on the active reference stations of the west cross-border zone of Ukraine. Methods. The zenith tropospheric delays, and their direct link with integrated / precipitated water vapor are important products that are obtained in GNSS-meteorology. They allow to get the rapid information for numerical weather prediction.

Methodological steps of GNSS meteorology

This paper highlights the gradual steps of GNSS meteorology realization. The structure of GNSS meteorology is represented in the introduction in general. The main feature of it is that the neutral atmosphere delays the passage of GNSS signal, causing the error in the measured distance is called tropospheric delay. If in geodesy a lot of efforts have been put to reduce this error to a desired level, then for meteorology this error was used as an important source of information about the state of moisture accumulation in atmosphere and its dynamics in space and time.