Hi -
You could use a coarser resolution mask and regrid it to your fine
grid, but of course you wouldn't have the same accuracy. Even etopo02
is very large as a global dataset.
What I was trying to say though, is that if your data is already marked
as missing over land, with the NaN's, you should be able to change the
ascii file so as to read it, and then I don't know that you'd need a
mask at all.
Ansley
Arturo Avila Rosas wrote:
Hi
Sorry my mistake, I am looking for 0.2 grade resolution
ocean mask. May I use etopo02 even though it has
different resolution?
Regards
Arturo
-----
Original Message -----
Sent:
Tuesday, February 16, 2010 5:15 PM
Subject:
Re: [ferret_users] Reading variables from an ascii file
Hi Arturo,
If your data has NaN at land locations then for ASCII data you should
just edit that or use your C program to change those values to some
known value out of the valid range of the data, and then after reading
the data do,
SET VAR/BAD=99999 sst
or whatever the variable name is. (Use the same kind of syntax to set
units for variables: SET VAR/UNITS="deg C" sst)
0.2 minute resolution is very high resolution! There is the etopo02
dataset which is 2 minutes' resolution.
Ansley
Arturo Avila Rosas wrote:
Hi Ansley,
Thanks a lot, it works fine!
Now, some data are over land and they are NaN values indeed. According
to "Setting a missing value" at Ferret FAQ having an ocean mask with
earth's surface may help to get only data over ocean, Where could I
find an ocean mask with earth's
surface at 0.2 minute resolution?
Cheers
Arturo
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