The BRAT and GUT Couple: Broadview Radar Altimetry and GOCE User Toolboxes

Américo Ambrózio (DEIMOS-ESRIN, Italy)


Marco Restano (SERCO-ESRIN, Italy); Jérôme Benveniste (ESA-ESRIN, Italy)

Event: 2020 Ocean Surface Topography Science Team Meeting (virtual)

Session: Outreach, Education and Altimetric Data Services

Presentation type: Type Forum only

The Broadview Radar Altimetry Toolbox (BRAT) is a collection of tools designed to facilitate the processing of radar altimetry data from all previous and current (and future) altimetry missions, including Sentinel-3 L1 and L2 products. A tutorial is included providing plenty of use cases on Geodesy & Geophysics, Oceanography, Coastal Zone, Atmosphere, Wind & Waves, Hydrology, Land, Ice and Climate. The Radar Altimetry Tutorial (RAT) can be consulted and downloaded at

BRAT's last version (4.2.1) was released in June 2018. Based on the community feedback, the front-end has been improved and simplified. The capability to use BRAT in conjunction with MATLAB/IDL or C/C++/Python/Fortran, allowing users to obtain desired data bypassing the data-formatting hassle, remains unchanged. Several kinds of computations can be done within BRAT involving the combination of data fields, that can be saved for future use, either by using embedded formulas including those from oceanographic altimetry, or by implementing ad-hoc Python modules created by users to meet their needs. BRAT can also be used to quickly visualise data, or to translate data into other formats, e.g. from NetCDF to raster images.

The GOCE User Toolbox (GUT) is a compilation of tools for the use and the analysis of GOCE gravity field models. It facilitates using, viewing and post-processing GOCE L2 data and allows gravity field data, in conjunction and consistently with any other auxiliary data set, to be pre-processed by beginners in gravity field processing, for oceanographic, hydrologic and solid earth applications at both regional and global scales. Hence, GUT facilitates the extensive use of data acquired by the GRACE and GOCE missions.

In the current version (3.2), GUT has been outfitted with a graphical user interface allowing users to visually program data processing workflows. Further enhancements aiming at facilitating the use of gradients, the anisotropic diffusive filtering, and the computation of Bouguer and isostatic gravity anomalies have been introduced. Packaged with GUT is also GUT's Variance/Covariance Matrix (VCM) tool, which enables non-experts to compute and study, with relative ease, the formal errors of quantities – such as geoid height, gravity anomaly/disturbance, radial gravity gradient, vertical deflections – that may be derived from the GOCE gravity models.

In our continuous endeavour to provide better and more useful tools, we intend to develop synergies between BRAT and SNAP (the Sentinel Application Platform). This will allow our users to easily explore the all the Sentinel data together. Any User or Space Agency are welcome to contribute to the evolution of the BRAT and GUT couple, especially in the preparation of future Altimetric and Gravity Missions.

BRAT and GUT toolboxes can be freely downloaded, along with text and video tutorials, ancillary material, auxiliary data and source code, at and
Américo Ambrózio