Re: converting from lambert projection to lat-lon projection (UNCLASSIFIED)

One of the nice NCL features is that it creates 'value added'
information when reading GRIB. When viewed from NCL,
the the lat/lon arrays look like this information was on the GRIB file.

You can plot the data directly ... there are numerous examples on
NCL's Application page.

If you want to interpolate the data to a different grid, then

   http://www.ncl.ucar.edu/Document/Functions/regrid.shtml

Specifically,
http://www.ncl.ucar.edu/Document/Functions/Contributed/rcm2rgrid_Wrap.shtml

David Brown wrote:
> Steve,
> Sorry I was not fully thinking this through. The GRIB file when read
> in through NCL will already have the lat/lon coordinates available as
> 2D arrays. The visual example I pointed to is only useful for getting
> these values if they are not already available. To actually regrid to
> a lat/lon projection requires one of the regridding functions. My
> first suggestion is still valid.
> -dave
>
>
> On Oct 23, 2009, at 11:24 AM, David Brown wrote:
>
>
>> Hi Steve,
>> You can look at the regridding page of the examples: http://www.ncl.ucar.edu/Applications/regrid.shtml
>> Especially take a look at the regridding decision tree.
>>
>> Another more visual solution is to use the technique of drawing a plot
>> of the data in its native projection, then using the ndctodata
>> function to get the lat/lon positions of the grid points. There is an
>> example of this technique on the "native grid projection" page: http://www.ncl.ucar.edu/Applications/native.shtml
>> . See the last example: native_5.ncl.
>> -dave
>>
>>
>> On Oct 23, 2009, at 10:53 AM, Kirby, Steve (Civ, ARL/CISD) wrote:
>>
>>
>>> Classification: UNCLASSIFIED
>>> Caveats: NONE
>>>
>>> Hi,
>>>
>>> I need to convert a GRIB1 format file I have, from lambert
>>> projection to a
>>> lat-lon projection.
>>>
>>> I noticed there was a thread on this in ncl-talk from Feb 2009 and
>>> Jin-Sheng
>>> Lin had posted some FORTRAN code called conv.f. I tried to pull it
>>> up but
>>> the link no longer worked. If that is still available, it would be
>>> great to
>>> be able to see it.
>>>
>>> Or, if there are some code/scripts under the NCL umbrella that do
>>> this type
>>> of conversion, would someone please point me to them.
>>>
>>> Thanks very much,
>>> skirby
>>>
>>> Classification: UNCLASSIFIED
>>> Caveats: NONE
>>>
>>> _______________________________________________
>>> ncl-talk mailing list
>>> List instructions, subscriber options, unsubscribe:
>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>
>> _______________________________________________
>> ncl-talk mailing list
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
>
> _______________________________________________
> ncl-talk mailing list
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>

-- 
======================================================
Dennis J. Shea                  tel: 303-497-1361    |
P.O. Box 3000                   fax: 303-497-1333    |
Climate Analysis Section                             |
Climate & Global Dynamics Div.                       |
National Center for Atmospheric Research             |
Boulder, CO  80307                                   |
USA                        email: shea 'at' ucar.edu |
======================================================
_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk