Global Navigation Satellite Systems; Troposphere; Zenith Total Delay; Integrated Water Vapour; Real-Time; Near Real-Time; Post Processing; Numerical Weather Prediction
Abstract :
[en] Modern Numerical Weather Prediction (NWP) models make use of the GNSS-derived Zenith Total Delay (ZTD) or Integrated Water Vapour (IWV) estimates to enhance the quality of their forecasts. Usually, the ZTD is assimilated into the NWP models on 3-hourly to 6-hourly intervals but with the advancement of NWP models towards higher update rates e.g. 1-hourly cycling in the Rapid update Cycle (RUC) NWP, it has become of high interest to estimate ZTD on sub-hourly intervals. In turn, this imposes requirements related to the timeliness and accuracy of the ZTD estimates and has lead to a development of various strategies to process GNSS observations to obtain ZTD with different latencies and accuracies. Using present GNSS products and tools, ZTD can be estimated in realtime (RT), near real-time (NRT) and post-processing (PP) modes. The aim of this study is to provide an overview and accuracy assessment of various RT, NRT, and PP IWV estimation systems and comparing their achieved accuracy with the user requirements for GNSS meteorology. The NRT systems are based on Bernese GPS Software 5.0 and use a double-differencing strategy whereas the PP system is based on the Bernese GNSS Software 5.2 using the precise point positioning (PPP) strategy. The RT systems are based on the BKG Ntrip Client 2.7 and the PPP-Wizard both using PPP. The PPP-Wizard allows integer ambiguity resolution
at a single station and therefore the effect of fixing integer ambiguities on ZTD estimates will also be presented.
Disciplines :
Earth sciences & physical geography
Author, co-author :
AHMED, Furqan ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Engineering Research Unit
TEFERLE, Felix Norman ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Engineering Research Unit
Bingley, Richard; University of Nottingham
Laurichesse, Denis; Centre National d'Etudes Spatiales, France
External co-authors :
yes
Language :
English
Title :
The Status of GNSS Data Processing Systems to Estimate Integrated Water Vapour for Use in Numerical Weather Prediction Models
Publication date :
2016
Event name :
International Association of Geodesy Scientific Assembly 2013
Event organizer :
International Association of Geodesy
Event place :
Potsdam, Germany
Event date :
01-09-2013 to 06-09-2013
Audience :
International
Main work title :
IAG 150 Years Proceedings of the 2013 IAG Scientific Assembly, Postdam,Germany, 1–6 September, 2013
FNR1090247 - The Potential Of Precipitable Water Vapour Measurements From Global Navigation Satellite Systems In Luxembourg, 2010 (01/06/2011-31/05/2015) - Furqan Ahmed
Name of the research project :
PWVLUX
Funders :
COST Action ES1206 FNR - Fonds National de la Recherche
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