Assimilation of GNSS Zenith Delays and Tropospheric Gradients: A Sensitivity Study utilizing sparse and dense station networks

Manuscript Submitted to: Geophysical Research Letters Manuscript title: Assimilation of GNSS Zenith Delays and Tropospheric Gradients: A Sensitivity Study utilizing sparse and dense station networks Authors: Rohith Thundathil, Florian Zus, Galina Dick, Jens Wickert Corresponding author: Dr Rohith Muraleedharan Thundathil Affiliation: Technische Universität Berlin, Germany; German Research Centre for Geosciences GFZ Potsdam, Germany Email: [email protected] List of contents in the digital repository: 1) WRFDAV4.4.1_GRADIENT_OPERATOR.tar The Weather Research and Forecasting model codes are in plain text format, which can be opened in any text reader. The model version is 4.4.1, and it includes the tropospheric gradient operator, which was added as an upgrade to the existing ZTD operator in WRF. 2) GOP_Control_Run_May_June_2013.tar.gz The DA simulation has 12-hour WRF outputs for May and June 2013. The control run is a conventional data-assimilated run. 3) GOP_Impact_Run_May_June_2013.tar.gz Control plus ZTD data assimilated 12-hourly WRF outputs for May and June 2013. GNSS data assimilation carried out from a dense network (0.5 degree). 4) GOP_Impact_Gradient_Run_May_June_2013.tar.gz Control plus ZTD plus gradient data assimilated 12-hourly WRF outputs for May and June 2013. GNSS data assimilation carried out from a dense network (0.5 degree). 5) GOP_1_0_Impact_Run_May_June_2013.tar.gz Control plus ZTD data assimilated 12-hourly WRF outputs for May and June 2013. GNSS data assimilation carried out from a sparse network (1.0 degree). 6) GOP_1_0_Impact_Gradient_Run_May_June_2013.tar.gz Control plus ZTD plus gradient data assimilated 12-hourly WRF outputs for May and June 2013. GNSS data assimilation carried out from a sparse network (1.0 degree).