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TRMM 2A56 Data Format


File name

2A56_HSTN_HAR_2270_200304_4.asc

2A-56   product ID
HSTN    GV Site
HAR     rain gauge network (in this case HAR=Harris County)
2270    rain gauge ID
200304  April 2003
4       file version
asc     ascii file

File header

2A-56 HSTN HAR 2270 W100_Buffa TIP 1.0 29.76222 -95.55750 KHGX 56.45 304.92 52 91 -99.9 04/07/2003 18:38 04/24/2003 15:52

2A-56 HSTN HAR 2270   same as in file name
W100_Buffa            name of rain gauge location
TIP                   rain gauge type: tipping bucket
1.0                   resoultion: 1 minute
29.76222              latitude in degree
-95.55750             longitude in degree
KHGX                  primary radar
56.45                 range, i.e. distance between primary radar and gauge
304.92                azimuth between primary radar and gauge
                      Azimuth is a direction in terms of the 360 degree compass;
                      north at 0, east at 90, south at 180, west at 270, etc.
52                    gauge coordinate in pixel at X axis
91                    gauge coordinate in pixel at Y axis
                      Radar location is at center pixel (75,75);
                      Pixel (0,0) is at the SW corner. One pixel is 2kmX2km.
-99.99                radar elevation above sea level. (-99.9 not available)
04/07/2003            start date
18:38                 start time (UTC)
04/24/2003            end date
15:52                 end time

Data format

...............................
2003 04 07 097 20 16 00   13.30
2003 04 07 097 20 17 00   18.83
2003 04 07 097 20 18 00   25.15
2003 04 07 097 20 19 00   31.36
2003 04 07 097 20 20 00   33.86
2003 04 07 097 20 21 00   32.81
2003 04 07 097 20 22 00   32.41
...............................
2003 04 20 110 21 03 00  -23.99
2003 04 20 110 21 04 00  -23.99
...............................


2003   year
04     month
07     day # in the month
097    Julian day #
20     hour (UTC)
16     minute
00     second
13.30  rain rate in mm/hr from 20:15:00 to 20:15:59
        negative sign '-' indicates low data quality due to interpolation.