• The above data files contain 2-D gridded global tropospheric ozone residual (TOR) data in Dobson Units derived from Version 7 EP-TOMS and collocated SBUV measurements.  The monthly files contain 12 arrays (Jan-Dec), while the seasonal files contain 4 arrays (DFJ, MAM, JJA, SON).  The monthly time elements are 1-12, while the seasonal are 1-4.

• 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.M[YYYY].nc        Seasonal:  TOR.S[YYYY].nc            [YYYY] = 4-digit year
Climatology:  Monthly:  TOR.CLIM.MONTH.1979-2005.nc        Seasonal:  TOR.CLIM.SEAS.1979-2005.nc

• Data type:  Gridded NetCDF 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 above Tropospheric Ozone Residual (TOR) files (in NetCDF format)
can be opened and displayed with an application, such as Grid Analysis
and Display System (GrADS), or with a programming language such as IDL.
If you're using GrADS to display the data, a descriptor file is needed.
An example is given below:	  

DSET ^TOR.JGR01.S1979.nc
TITLE Tropospheric Ozone Residual
UNDEF -77.0
XDEF x 288 LINEAR -179.375 1.25 
YDEF y 100 LINEAR -49.5 1
TDEF time 12 LINEAR JAN1979 1mo
VARS 1
TOR=>tor 1 99 Tropospheric Ozone Residual 
ENDVARS	  

• 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.