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20010406: time issues in meteosat imagery

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  • Subject: 20010406: time issues in meteosat imagery
  • Date: Fri, 06 Apr 2001 16:44:41 -0600
>From: address@hidden (Chris Hennon)
>Organization: Ohio State University
>Keywords: 200104061848.f36ImGL26255 McIDAS METEOSAT time

Chris,

>For some reason, many of the meteosat-7 images I've been collecting have a
>time value of 24:00:00 instead of 00:00:00:

This is bad since 24:00:00 is not recognized as a valid time in McIDAS.

>IMGLIST METSAT-7.230 242                                                      
>         
>Image file directory listing for:METSAT-7                                     
>         
> Pos Satellite/         Date       Time      Center   Band(s)
>     sensor                                 Lat  Lon
> --- -------------  ------------  --------  ---- ---- ------------
> 230  METEOSAT7     27 NOV 98331  24:00:00     0    0 8
> 231  METEOSAT7     28 NOV 98332  06:00:00     0    0 8
> 232  METEOSAT7     28 NOV 98332  12:00:00     0    0 8
> 233  METEOSAT7     28 NOV 98332  18:00:00     0    0 8
> 234  METEOSAT7     28 NOV 98332  24:00:00     0    0 8
> 235  METEOSAT7     29 NOV 98333  06:00:00     0    0 8
> 236  METEOSAT7     29 NOV 98333  12:00:00     0    0 8
> 237  METEOSAT7     29 NOV 98333  18:00:00     0    0 8
> 238  METEOSAT7     29 NOV 98333  24:00:00     0    0 8
> 239  METEOSAT7     30 NOV 98334  06:00:00     0    0 8
> 240  METEOSAT7     30 NOV 98334  12:00:00     0    0 8
> 241  METEOSAT7     30 NOV 98334  18:00:00     0    0 8
> 242  METEOSAT7     30 NOV 98334  24:00:00     0    0 8
>IMGLIST: done
>
>This presents a problem because when I try to list them, I am not allowed:
>
>IMGLIST METSAT-7.ALL TIME=24
>Image file directory listing for:METSAT-7
>IMGLIST: CXADIR CALLED WITH BAD TIME 24
>IMGLIST: done

Right.  The interface is enforcing the concept that times can range from
00:00:00 to 23:59:59.

>Hence I can't process the images in my script that you've shown
>me how to use (GEWCOMP2), since it can't process the number '24'.  Is
>there a workaround (without manually changing all of the times to '00')?

I believe that you will need to change those times from 24:00:00 to 00:00:00.
This is not hard.  You will need to use the IMGCHA command to do it:

IMGCHA METSAT-7.230 TIME=00:00:00

>Thanks.

You can roll IMGCHA into a little McBASI script that does a complete list
and then reads back in the images that have 24:00:00 as their time and
then change them in one go.

Tom