Monthly Data: The following table contains monthly-averaged TOR data (January through December) in ascii format from 1979-2005. The last column (CLIM) is the monthly climatology for this time period. NOTE: Years without any available coverage were 1994, 1995, and 1996. If there is no link for a particular month, it means that no data are available. The data are in Dobson Units.

Seasonal data: The following table contains seasonally-averaged TOR data (DJF, MAM, JJA, SON) in ascii format from 1979-2005.   The last column (CLIM) is the seasonal climatology for this time period. 
NOTE:  Years without any available coverage were 1994, 1995, and 1996.  If there is no link for a particular season, it means that no data are available.  The data are in Dobson Units.

• Data points were required to meet the following criteria:
  1.  TOR < 80 Dobson Units
  2.  TOMS values < 400 Dobson Units
  3.  Tropopause pressure < 253 mb
  
 
• File naming convention:
  Monthly:   TOR.[MMM].[YYYY].asc
       [MMM] = 3-letter monthly abbreviation (i.e., JAN, FEB,...,DEC)
       [YYYY] = 4-digit year
  Seasonal:  TOR.[SSS].[YYYY].asc
       [SSS] = 3-letter seasonal abbreviation (DJF, MAM, JJA, SON)
       [YYYY] = 4-digit year
  Climatology:
              Monthly => TOR.CLIM.[MMM].asc       
       [MMM] = 3-letter monthly abbreviation (i.e., JAN, FEB,..., DEC)
              Seasonal => TOR.CLIM.[SSS].asc       
       [SSS] = 3-letter seasonal abbreviation (DJF, MAM, JJA, SON)

• Data type:  Ascii Data

Longitudes:  288 bins centered on 179.375W to 179.375E  (1.25 degree steps)
Latitudes:     100 bins centered on 49.5 S to 49.5 N (1.00 degree steps)

• Example array location:

array (0,0) corresponds to (49.5S, 179.375W)
array (0,288) corresponds to (49.5S, 179.375E)
array (100,0) corresponds to (49.5N, 179.375W)
array (100,288) corresponds to (49.5N, 179.375E)
 
• Data not meeting criteria:  -77

The ascii TOR files are gridded and in plain text format, and can be read by most text editors.
Each file is 288 (# of longitudes) x 100 (# of latitudes).
The center of each grid point, including the degree steps, are shown in the Data Format section above.    

• If you use any of the data listed above, please include the following reference:
• Fishman, J., A.E. Wozniak, and J.K. Creilson, Global distribution of tropospheric ozone from satellite measurements using the empirically corrected tropospheric ozone residual technique: Identification of the regional aspects of air pollution, Atmos. Chem. Phys., 3, 893-907, 2003.
• Visit the Publications and Presentations page for a copy of this paper.