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Notes on reading Atlantic RTOFS Model Data via Ferret

Home Compare with Obs* Data Assim* Monitor* RTOFS & WOCE* Graphics Viewer* Data Access About the Model
* -- MMAB internal use only

Ferret is an interactive computer visualization and analysis environment designed to meet the needs of oceanographers and meteorologists analyzing large and complex gridded data sets. It runs on most Unix systems, and on Windows XP/NT/9x using X-windows for display. It can transparently access extensive remote Internet data bases using OPeNDAP (formerly known as DODS).

Click here for more information on Ferret.

To use Ferret to convert GRiB to NetCDF files:


Download the version of Ferret appropriate for your operating system from:
Follow the instructions provided by the Install Guide.


Create a script -- for example calling it go.jnl:

(the script starts with the next line)

use ""
save/ wtmpdsl

(end of script)

the above example is for writing temperature in netCDF format and where
I = 400 to 1000; J = 400 to 1684 for for Time slice L=1

To change the date:
change rtofs20070828 to a different date as in:
rtofsyyyymmdd yyyy is a 4-digit year, mm is month and dd is day

example: rtofs20070828

and change and I and J to the range you want and L to the forecast time you want
(1 is nowcast, 2: 24-hr forecast, 3: 48-hr forecast, 4: 72-hr forecast,
5: 96-hr forecast and 6: 120-hr forecast)

for other parameters/fields available check the link:

(where rtofsyyyymmdd; yyyy-year, mm-month, dd-day; example: rtofs20070828)


In Unix-type environments you can run Ferret using the command:

ferret -batch -script < go.jnl
this will generate the NetCDF file you want.

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Page last modified: Monday, 23-Apr-2018 22:01:08 UTC