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Grib.exe – B&G Deckman User Manual

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GRIB tools

9.9

allows you to select the time you wish to use, and the small box beside
this controls the type of data (wind, pressure, current, temperature).

The GRIB area section allows you to specify the latitude and longitude
of the centre of the area you wish to cut (in degrees: positive is North
and East, negative South and West) and the total range across the area.
Projection allows you to cut a different area of the GRIB at different
times: enter a Bearing for the direction in which you want to move and
a Step (units nautical miles per day).

If a particular file contains too much detail (for instance, if the files are
too large), the Resolution boxes allow you to skip some of the data
(include all, or one out of 2, 3 or 4 data points). If the Same Resolution
check box is ticked when you change the resolution for a particular
forecast time, this resolution also applies for all times in the forecast.
The Save this GRIB check box allows you to specify which forecast
times you wish to include: step through the forecast times and clear the
check box for those times you do not want included.

When you are happy with your selections, select OK and you will be
prompted for a file name and directory to save the new file.

GRIB.exe

This program allows you to view the raw data from a GRIB file (which
may be useful for diagnostic purposes) and also allows you to convert
GRIBs to a format readable by Deckman (see GRIB routing below).

Run the program GRIB.exe

from the c:\program

files\BandG\deckman\GRIB directory (where 'C' is the program where
Deckman is installed). In this program, select File>Open and then select
the GRIB file you wish to use—you may have to specify the directory.
The GRIB file will look very confusing in the format in which it first
comes up—not much more than a jumble of numbers. However, the
brief explanation below should help you to make some sense of things.

The first things to understand are a few of the code numbers used in
GRIB files: