NESDIS Total Ozone from Analysis of Stratospheric and Tropospheric components (TOAST) -
TOAST combines UV and IR ozone retrievals from an algorithm using the Solar Backscatter Ultraviolet Version 2 (SBUV/2) and the Cross-track Infrared Sounder (CrIS) instruments. This daily Total Ozone Analysis is an enhanced version of the previous TOAST product using SBUV/2 and the Advanced Tiros-N Operational Vertical Sounder (TOVS). The most significant improvement of the algorithm is in the IR-derived product replacement of the column amount retrievals from the High resolution InfraRed Sounder (HIRS) with the CrIS profile retrievals. This improvement allows the algorithm to provide global 1 degree x 1 degree total ozone amounts and profile maps at 12 Umkehr layers. The new products have significantly increased accuracy in tropospheric ozone estimation. The TOAST data archive contains UV, IR and blended products in direct access binary data format, and blended products in GRIB format. The direct access binary files have record length of 260640 bytes, which represent a 360x181 array of 4-byte floating point values for the two-dimensional global 1×1 degree gridded analysis. The first data value in a record is for the point centered at (0.5 deg East, 90 deg South). See metadata documentation for more information on the TOAST direct access binary format and grid. These operational products were produced by the NOAA/NESDIS Office of Satellite and Product Operations (OSPO). The enhanced TOAST products have been operational since 2014, however the archive period of record begins in 2016. See the Details Section below for more information.
Details - Metadata, Documentation
CLASS Archive Begin Date
CLASS Archive End Date
Horizontal Resolution Range: 100 km - < 250 km or approximately 1 degree - < 2.5 degrees
The TOAST product files provide two-dimensional (360x181) ozone information on a regular fixed global grid of latitude and longitude. The binary formats require ancillary latitude and longitude files for navigation. The latitude and longitude values are representative of grid cells centered at longitudes from Greenwich 0 degrees eastward to 359 deg, and latitudes from 90 deg South northward to 90 deg North, both with 1 degree spacing. That is, the value in a typical OZONE [I,J] element is for a 1x1 degree cell centered at longitude I-1 deg East, latitude J-91 deg North. For example, OZONE [201,151] is centered at Longitude 200 deg East (160 deg West), latitude 60 deg North. The two navigation files TOAST_lat_lon.txt and TOAST_lat_lon.bin provide the coordinates of the 181 latitude values in deg North followed by the 360 longitude values in deg East. The binary format for the IR TOAST and the Blended (UV+IR) TOAST products is a 4-byte array with dimensions of 360x181. The UV TOAST binary format, however, is a 4-byte array with dimensions of 360x181x13, where 13 is the UV sensor's total column ozone amount followed by ozone amounts at 12 Umkehr layers at atmospheric pressure levels 0.25, 0.5, 0.99, 1.98, 3.96, 7.93, 15.8, 31.7, 63.3, 127, 253, and 1013 hPa.