The WESS4T web application has been developed for training purposes.

You may register for a better experience: Registered users are able to save Projects. A project consists of an instrument and a profile number, you may create as many projects as you want.

Two mains tools are available in the WESS4T application: Simulation and Retrieval . You must select an instrument from the database and a profile before to be able to access the simulation and the retrieval tools.

The available profiles consist in the temperature subset of the NWPSAF profile dataset. For the WESS4T application the profiles have been interpolated on the 54 levels of the RTTOV models and converted into HDF5 format.

Simulation uses RTTOV, the fast radiative transfer model developed by the NWP SAF.

For the simulation, you may change the satellite zenith angle and the surface emissivity and you can choose to display or not the results of the K-Model (Jacobian) as well as the result of the Direct Model (brightness temperatures and radiances).

On land, for Infra-Red simulations, you may choose between a fixed emissivity of 0.98 and an atlas (CAMEL 2007).

On land, for Micro-Wave simulations, you may choose between a fixed emissivity of 0.98, a model (FASTEM) and an atlas (TELSEM2).

On sea you may choose between a fixed emissivity and a model (FASTEM for Micro-Wave and IREMIS for Infra-Red).

You may launch up to 3 simulations, the differences between the different runs are displayed.

More information about the RTTOV options, atlases and emissivity models can be found in the RTTOV user guide .

For the simulation, you may apply a modification of the profile: you may change the surface temperature, apply an offset on the temperature profile and a scaling factor on the humidity profile.

Retrieval uses the RTTOV GUI "1DVAR" python module based on a simple algorithm and the B (background error covariance) and R (observation error covariance) matrices of the SAFNWP 1D-Var software.

For the retrieval, the profile you have chosen will be your true profile, the US 76 standard atmophere will be used as the background profile. You may choose to use all the channels of the instrument or only a subset. You have the possibility to perform up to 4 retrievals. More information about the algorithm used for the retrieval can be found here, in this poster from the ITSC-XX, and here, in the proceeding paper.

The WESS4T plots are created with Plotly and are fully responsive, You can use the plotly icons in the right top corner of each plot to zoom, and reset axes, and to save the plots as png files.