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GRIB files are represented by this icon in the user interface:

Examining GRIB contents

The contents of a GRIB file can be inspected with the GRIB Examiner, which can be either started up from user interface (right-click examine on the icon) or from the command line using the following command:

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On top of the map-based visualisation we can also generate the following plot types from GRIB data:

It is also possible to extract vertical profiles (see Vertical Profile Data and Vertical Profile View) and time series from GRIB data.

The With the Thermo Data icon icon  we can extract prepare thermodynamic profiles which can then can  be visualised in a tephigram, a skew-t or in an emagarm emagram using Thermo View.

Filtering and interpolation

The GRIB Filter icon provides the means to select a subset of fields from a GRIB file. It (and the MARS Retrieval icon) also contains some parameters, such as Grid, which allow for interpolation to a new grid.

Data processing

There are quite a few icons available in Metview to process GRIB data. These include the icons mentioned above and the following other icons:

Metview's script interface provides access to all these icons and also offers a rich set of functions and operators to work with GRIB data (see Script Language Support below).

Retrieval from MARS

If you (and your Metview instalMetview has access to ECMWF's MARS archive, GRIB data can be retrieved via the Mars Retrieval icon. At ECMWF MARS access is set up on all computer systems, while outside ECMWF the MARS Web API could be used in Metview following the setup instructions here.

Script language support

Metview provides full support for GRIB from its Macro and Python interfaces. In script GRIB data is represented as a fieldset, which can be imagined as a list of GRIB messages. Fieldset handling probably Metview's richest and most powerful interface. The full list of available functions and operators on fieldsets can be found on the Fieldset Functions page. For examples on how to use ODB from script please see the tutorials and study the Gallery and Thermodynamic functions pages.

Tutorials

The main tutorial about using ODB in Metview can be found here. There is also a shorter tutorial available on this page.

The Gallery features a few ODB-related examples showcasing both the ODB Filter and ODB Visualiser icons.

lation) have access to a MARS archive, Metview can retrieve GRIB data via the Mars Retrieval icon. Once the data has been retrieved, the icon text will turn green to indicate that it has been cached; operations such as Visualise and Examine will work on the cached data. If any of the parameters in the Mars Retrieval icon are changed, or if Metview is restarted then the cached data will be removed.

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There is no dedicated tutorial for GRIB but the bulk of the Data analysis and visualisation using Metview online course is dealing with visualisation and processing of GRIB data. There is also the ECMWF New Users Metview Tutorial which provides an excellent introduction to Metview and GRIB handling.


FAQ

In Metview's FAQ page a whole section is devoted to GRIB-related questions.

Most of the Gallery examples are related to GRIB data. Actually, all the plots shown on this page were taken from the Gallery (clicking on them leading to the actual code).