Total Ozone Mapping Spectrometer Data held at the British Atmospheric Data Centre

The TOMS (Total Ozone Mapping Spectrometer) dataset consists of daily
gridded measurements of integrated column ozone, expressed in terms of the
equivalent thickness the layer would have if brought to STP.

This thicknes is measured in Dobson Units (DU) where one DU is
equivalent to 0.01mm.

TOMS instruments have been flown on two satellites providing the
following temporal coverage:
Nimbus-7, spanning 1st November 1978 - 6th May 1993 and
Meteor-3, spanning 22nd August 1991 - 27th December 1994.

BADC holds all available data online.
Nimbus-7 data processed using software of Version 6 or greater, and all
Meteor-3 data, is stored in ASCII files.
Nimbus-7 Version 5 data is written in CDF format

All the ASCII data uses a grid with 288 longitude cells per one-degree
latitude zone.

Nimbus-7 Version 5 data uses a variable number of longitude cells
in order to give a roughly constant cell area over the globe. The number
of cells ranges from 288 at the equator to 72 at the poles as follows:
0--50 deg. (288 cells),
50--70 deg. (144 cells) and
70--90 deg. (72 cells).

In the later (Version 6 onwards) Nimbus and Meteor data, groups of two
orfour cell values are repeated in order to fill the storage grid.

The TOMS instrument measures backscattered UV at 312.5, 317.5, 331.3,
339.9, 360.0 and 380.0 nm.

The first four wavelengths are sensitive to ozone while the two longer
wavelengths are used to estimate the scene reflectivity needed to derive
ozone amounts.

The instrument views the whole globe once per day but ozone amounts
can only be derived for sunlit regions, ie there are no data above the
winter poles.

Other experiments on the Nimbus-7 satellite:
Coastal Zone Colour Scanner - CZCS
Earth Radiation Budget - ERB
Limb Infrared Monitor of the Stratosphere - LIMS
Stratspheric Aerosol Measurement II - SAMII
Stratospheric and Mesospheric Sounder - SAMS
Solar Backscatter Ultraviolet - SBUV
Scanning Multichannel Microwave Radiometer - SMMR
Temperature Humidity Infrared Radiometer - THIR