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
Bennitt G, Levick T (2011) The impact of assimilating zenith total delay measurements from ground-based GNSS receivers in the Met Office numerical weather prediction UK model. Geophys Res Abstr 13:EGU2011-6705
Bevis M, Businger S, Chiswell S, Herring TA, Anthes RA, Rocken C, Ware RH (1994) GPS meteorology: Mapping zenith wet delays onto precipitable water. J Appl Meteorol 33:379–386. doi:10.1175/1520-0450(1994)033<0379:GMMZWD>2.0.CO;2
Byram S, Hackman C, Slabinski V, Tracey J (2011) Computation of a high-precision GPS-based troposphere product by the USNO. In: Proceedings of the 24th International Technical Meeting of the Satellite Division of the Institute of Navigation ION GNSS 2011, pp 572–578
Byun SH, Bar-Sever YE (2009) A new type of troposphere zenith path delay product of the International GNSS Service. J Geodesy 83(3–4):1–7
Dach R (2013) Bernese GNSS Software: new features in version 5.2. Astronomical Institute, University of Bern, Bern
Dach R, Brockmann E, Schaer S, Beutler G, Meindl M, Prange L, Bock H, Jäggi A, Ostini L (2009) GNSS processing at CODE: status report. J Geodesy 83(3–4):353–365
Dach R, Hugentobler U, Fridez P, Meindl M (2007) Bernese GPS Software Version 5.0. Astronomical Institute, University of Bern, Bern
De Haan S (2011) Impact of GPS ZTD on rainfall estimates in an hourly update cycle of a numerical weather prediction model. Geophys Res Abstr 13:EGU2011-4222
Dow John M, Neilan RE, Rizos C (2009) The International GNSS Service in a changing landscape of Global Navigation Satellite Systems. J Geodesy 83(3–4), 191–198
Elgered G, Plag H-P, Marel H, Barlag S, Nash J (eds) (2005) Exploitation of ground-based GPS for operational numerical weather prediction and climate applications, EUR 21639, Luxembourg, 2005 [ISBN 92-898-0012-7]
Gutman S, Sahm SR, Benjamin SG, Schwartz BE, Holub KL, Stewart JQ, Smith TL (2004) Rapid retrieval and assimilation of ground based GPS precipitable water observations at the NOAA forecast systems laboratory: impact on weather forecasts. J Meteorol Soc Jpn Ser II 82(1B):351–360
Laurichesse D (2011) The CNES real-time PPP with undifferenced integer ambiguity resolution demonstrator. In: Proceedings of the 24th International Technical Meeting of The Satellite Division of the Institute of Navigation ION GNSS 2011, pp 654–662
Nilsson T, Elgered G (2008) Long-term trends in the atmospheric water vapor content estimated from ground-based GPS data. J Geophys Res 113(D19). doi:10.1029/2008JD010110
Offiler D (2010) Product requirements document version 1.0 – 21 December 2010. EIG EUMETNET GNSSWater Vapour Programme (E-GVAP-II)
Stende M (2006) Monitoring climate variability and change by means of GNSS data. In: Foelsche U, Kirchengast G, Steiner A (eds) Atmosphere and climate, pp 275–285. Springer, Berlin/Heidelberg. doi:10.1007/3-540-34121-8_23
Teke K, Böhm J, Nilsson T, Schuh H, Steigenberger P, Dach R, Heinkelmann R, Willis P, Haas R, Garca-Espada S, Hobiger T, Ichikawa R, Shimizu S (2011) Multi-technique comparison of troposphere zenith delays and gradients during CONT08. J Geodesy 85(7):395–413
Vedel H, Huang XY, Haase J, Ge M, Calais E (2004) Impact of GPS zenith tropospheric delay data on precipitation forecasts in Mediterranean France and Spain. Geophys Res Lett 31(2). doi:10.1029/2003GL017715
Weber G, Mervart L (2012) BKG Ntrip Client (BNC) Version 2.7 Manual. Federal Agency for Cartography and Geodesy, Frankfurt, Germany
Zumberge JF, Heflin MB, Jefferson DC, Watkins MM, Webb FH (1997) Precise point positioning for the efficient and robust analysis of GPS data from large networks. J Geophys Res 102(B3):5005–5017. doi:10.1029/96JB03860
