Getting Data into Metview
Copying files and creating links
By default, Metview can only see files under the $HOME/metview directory. You can select a different home directory for Metview (-u option on the Metview startup command line), but you can also copy files into this directory (or a sub-directory of it) or create links to external data files - this can be useful if you have large data files which would exceed the quota in your home directory.
One way is to do this from a shell command line (ln command), but Metview can also create these links for you.
Right-click an empty spot in the Metview desktop and choose Create New… Link to File and type /home/ectrain/trx/mv_data/ztuv.grb into the File name box (or navigate there and select the file with the mouse). Note that the text label under the new icon is in italics, and there is an arrow in the bottom-left corner - these indicate that this is a link; if you hover the mouse cursor over the icon, the link details will be shown in the status bar. The padlock in the bottom-right corner tells us that this file is read-only. This file contains analysis and 1, 2, 3, 4 and 5-day forecasts for geopotential, temperature and wind at various pressure levels – visualise it to see for yourself.
You can create links to individual files or complete folders. This facility can be used to share folders between users.
Retrieving data from MARS
Metview has the ability to retrieve data directly from the ECMWF MARS archive (or indeed any other MARS archive installed outside ECMWF).
Create a new Mars Retrieval icon. Edit it and set only the following:
| Grid | 1.5/1.5 |
This ensures that the data is transformed onto a regular 1.5 degree grid. Much of Metview's functionality relies on GRIB data being on a grid (regular or quasi-regular) and not stored as spherical harmonics.
If you look at the other parameters in the icon editor, you will see that by default, it will retrieve analysis data (Type = An) of geopotential (Param = Z) on six pressure levels (Levelist = 1000/850/700/500/400/300) for yesterday (Date = -1).