On-Line Weather Maps

• To: all-at-sio@xxxxxxxxxxxx
• Subject: On-Line Weather Maps
• From: Larry Riddle <lriddle@xxxxxxxx>
• Date: Mon, 30 Oct 2000 17:32:59 -0800

SIO Weather Map Users:

There are several on-line weather map users here at SIO.  I don't know who you are, so 
this is being sent to "all-at-sio".  If you're neither a weather map user, nor 
interested in weather maps, you've probably gone as far into this message as you'll find 
interesting.

The National Weather Service has announced the final sundown date for DIFAX 
weather maps (next Spring).  For those who go to sea, I'm not sure whether or 
not this will have any affect on WEFAX products, assuming those are still 
broadcast at all.  However, the current set of DIFAX products is accessible 
from sea via the internet (see below).

For those who want to see what the DIFAX products look like, go to the SIO Weather Page 
(http://meteora.ucsd.edu/weather.html) and click on the quick pointer for "Real Time Data".  There is a 
pointer there for "Current NWS Difax Charts". Click on that and it will bring up a laundry list of current 
DIFAX charts.  Note: this is only available from hosts ending in ".ucsd.edu" or ".sdsc.edu".  Sorry 
for this, it is the usual lawyers and contractual agreements thing.

I will be attending a meeting in Boulder, Colorado next week.  This is the Fall 
Users Committee meeting of Unidata, an organization of over 150 colleges and 
universities that teach and/or perform research in the atmospheric/oceanic 
sciences.  Part of the agenda is what, if anything, we (the university 
atmospheric/oceanic sciences community) should do about this problem.  I would 
like some input from you to present at this meeting so I'll have something 
beyond my own prejudices to talk about.

All of the images mentioned above (found on the SIO Weather Page) are in PCX 
format.  If your browser/computer system doesn't know how to handle this 
format, sorry again.  This is another problem to be discussed next week.  
Should map graphics be sent out as postscript or fax-format files (easy to 
print, but hard to view on a computer screen)?  Or should they be sent out as 
image files (GIF, PCX, TIF, PNG, etc.) which are easy to view on a computer 
screen, but harder to print?

One option being discussed is to do nothing.  This is not a popular solution, 
but it is a possible solution.  DIFAX and DIFAX like products will just go 
away.  Every school and institution will locally generate whatever products it 
deems desirable.  That would require constantly circulating images to each 
person in a non-local (cross country/international/etc.) discussion group 
(either email or telephonic) so that all are looking at the same thing.

A second solution, the current preferred option, is to set up a standard set of computer scripts 
that generate a standard set of maps.  This would require that all sites would run the same 
software (not a problem as the software is "free"), but would otherwise answer most of 
the problems in solution one.  A problem that isn't solved is that the same software, using the 
same input scripts and data, does not always arrive at the same exact answer when the platforms 
and/or operating systems are different (Sun/DEC/HP/etc).  The solutions aren't "wrong", 
just slightly different.

A third solution, my personal preference, is for a subset of sites (all on the 
same platforms and running the same software and script versions) to generate a 
suite of DIFAX like products that are distributed using the same methodology 
that currently handles the real time data.  This would allow two users on 
different sides of the country to look at the exact same product without having 
to jump through too many hoops.  Doing this at more than one site allows for 
one site to fail (hardware, power, etc.) without shutting down the entire 
system.

I will appreciate your comments.

Larry