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GOES: Geostationary Operational Environmental Satellites

The National Weather Service (NWS) uses the GOES system for its United States weather monitoring and forecasting operations, and scientific researchers use the data to better understand land, atmosphere, ocean, and climate interactions. The GOES system uses geosynchronous satellites which—since the launch of SMS-1 in 1974—have been a basic element of U.S. weather monitoring and forecasting.

Four GOES satellites are currently available for operational use:

    1) GOES-12 is designated GOES-South, currently located at 60°W 
    2) GOES-13 is designated GOES-East, currently located at 75°W. 
       It provides most of the U.S. weather information.
    3) GOES 14 was placed in orbit on 7 July 2009, underwent Post-Launch Testing
       until December 2009 and then was placed in on-orbit storage at 105° W.
    4) GOES 15 is designated GOES-West, currently located at 135°W over the 
       Pacific Ocean.
goes_1.ncl: A GOES-11 plot.

goes_2.ncl: A GOES-12 plot. The script handles bogus values by assigning outliers to an _FillValue attribute. Since the lat/lon have missing values, you must set res@trGridType to "TriangularMesh".

The file has issues. Specifically, the lat and lon have
bogus values

(0)    min(lat)=-79.7354   max(lat)=2.14329e+09  <===
(0)    min(lon)=-156.169   max(lon)=2.14329e+09  <===

%> ncdump -v lat,lon | less

        float data(time, yc, xc) ;
                data:long_name = "0-255 Brightness Temperature" ;
                data:type = "VISR" ;
                data:coordinates = "lon lat" ;
        float lat(yc, xc) ;
                lat:long_name = "lat" ;
                lat:units = "degrees_north" ;
        float lon(yc, xc) ;
                lon:long_name = "lon" ;
                lon:units = "degrees_east" ;

There is no indication of a '_FillValue' or' missing_value' attribute
for lat, lon or data.

The data variable should have (I think)
        data@_FillValue = 255 

goes_3.ncl: A GOES-15 plot. The lat/lon data has the same issues as the GOES-12 plot above.

Additionally, the longitude values cross the dateline, so we fix these values by adding 360. Finally, to speed up plotting, we only plot every 10th value.

goes_4.ncl: Another GOES-12 plot for a very small region. above.

goes_5.ncl: A GOES-13 plot. above.