20020212: 20020212: reading/writing McIdas area files for use in GEMPAK

David,

My note means that if you have an AREA file in TANC projection,
GEMPAK will be able to plot it. MCIDAS calls a LAMBERT Tangent
projection TANC as a separate projection from LAMB. GEMPAK
will call these both LCC. The secant projection will have
different la1 and la2 values. The tangent projection will
have la1=la2. 

Sure you can center a TANC projection over Washington.

Steve Chiswell




>From: David Ovens <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200202121940.g1CJeYx23140

>Steve,
>
>Does this mean that TANC does what I want and I should just figure out
>how to use it?
>
>David
>
>Unidata Support wrote:
>> 
>> 
>> David,
>> 
>> I added the TANC projection to the imar2gm.f routine in the
>> patches area of the GEMPAK downloads. The McIDAS routine for 
>> TANC does hardcode the radius of earth, and not stored in the 
>> navblk.
>> 
>> I'll let Tom address creating AREA files.
>> 
>> Steve Chiswell
>> Unidata User Support
>> 
>> 
>> >From: David Ovens <address@hidden>
>> >Organization: UCAR/Unidata
>> >Keywords: 200202121913.g1CJDNx21764
>> 
>> >Hello,
>> >
>> >I am hoping to create a bogus McIdas area file -- basically a GOES-10
>> >image rotated up so Seattle is about at the center of the image -- so
>> >that I can get a different satellite projection in GEMPAK (if you want
>> >an example of what my output would look like, see 
>> > http://www.atmos.washington.edu/~ovens/loops/wxloop.cgi?joes_okc_h500+all
>> >).  Anyhow, I think that all I need to do is figure out how to read an
>> >existing McIdas file (GOES-10) and write it back out changing only the
>> >4th word in the navigation section from "102042" to "474500" or
>> >something like that.  Is there FORTRAN (preferably), C, or PERL code
>> >out there that could help me with this?
>> >
>> >By the way, I have looked at maknav and imgremap in McIdas-X and I
>> >understand the LAMB, MERC, PS, RADR, RECT, and MOLL projections, it's
>> >possible that SIN, TANC, or NOAA does what I want, but I don't
>> >understand those.  Basically, I didn't see how I could do a new
>> >satellite projection if I did not already have a file with the
>> >projection that I want to create.
>> >
>> Thanks for any help or suggestions.
>> >
>> >David
>> >-- 
>> >
>> >David Ovens         e-mail: address@hidden
>> >(206) 685-8108          plan: Real-time MM5 forecasting for Pacific Northwe
> st
>> >Research Meteorologist
>> >Dept of Atmospheric Sciences, Box 351640
>> >University of Washington 
>> >Seattle, WA  98195
>> >
>> 
>> ****************************************************************************
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>
>
>-- 
>
>David Ovens            e-mail: address@hidden
>(206) 685-8108          plan: Real-time MM5 forecasting for Pacific Northwest
>Research Meteorologist
>Dept of Atmospheric Sciences, Box 351640
>University of Washington 
>Seattle, WA  98195
>