Presentation information


IAG Symposia » G06. Geodetic remote sensing

[G06-1] Troposphere monitoring I

Tue. Aug 1, 2017 1:30 PM - 3:00 PM Room 504+505 (Kobe International Conference Center 5F, Room 504+505)

Chairs: Yoshinori Shoji (Meteorological Research Institute Tsukuba) , Robert Heinkelmann (German Research Centre for Geosciences Potsdam GFZ)

2:30 PM - 2:45 PM

[G06-1-05] Heterogeneity of residuals from GNSS and ray-traced tropospheric delays as an indicator of hydrometeors

Pawel Hordyniec, Witold Rohm, Jan Kaplon (Wroclaw University of Environmental and Life Sciences, Institute of Geodesy and Geoinformatics, Wroclaw, Poland)

We attempt to indicate hydrometeors content along ray-path trajectories between ground-based receivers and respective GNSS satellites. Using tropospheric delays retrieved from GNSS data in Precise Point Positioning (PPP) and associated ray-traced delays in Numerical Weather Prediction (NWP) model, we are able to calculate residuals resulting from different processing approaches. When precise satellite orbits and clocks are applied, GNSS post-fit residuals carry the troposphere information except of multipath and residual antenna Phase Centre Variations (PCVs). After post-fit residuals are reduced by site-dependent systematic effect, they are introduced to GNSS-based delays increasing discrepancies with respect to ray-traced delays. Assuming the hydrometeor information in GNSS solution is correct, we expect the effect to be significant during severe weather events since ray-traced tropospheric delays exclude aerosols contributions. We conducted spatial and temporal correlation analysis of the slant delay residuals (GNSS minus ray-traced) with weather phenomena recorded during the COST ES1206 GNSS4SWEC benchmark period (May 5th - June 29th, 2013). We also discuss results that arise from different GNSS PPP slant delay estimation approaches related to coordinates constraining and inclusion of ZTD horizontal gradients.