These data consist of sets of 3-dimensional gridpoint analyses of the stratosphere which are produced by the Met Office using data from the TIROS Operational Vertical Sounder (TOVS) instruments onboard the NOAA operational polar orbiters. TOVS consists of 3 instruments, the Stratospheric Sounding Unit (SSU) the Microwave Sounding Unit (MSU) and the High Resolution Infrared Sounder (HIRS). The instruments are described in more detail in the BADC help file

The primary products which are archived at the BADC are synoptic fields of measured radiances and geopotential height. The radiances from 8 of the TOVS channels with weighting functions distributed throughout the stratosphere are stored on a 5 degree latitude by 5 degree longitude grid, whilst the geopotential heights are stored on the same latitude/longitude grid on the 850, 500, 300, 200, 100, 50, 20, 10, 5, 2 and 1 hPa pressure surfaces. The analyses were produced from December 1978 until June 1998.

Also available are monthly means of height, temperature, and geostrophic winds for the period January 1979 to December 1997, as well as gradient winds calculated from monthly mean heights for the period January 1979 to December 1997.

Software is available to calculate brightness temperatures from the radiances and temperatures and geostrophic winds and potential vorticity from the geopotential height fields.

The Met Office wish to monitor the use of this data and require an acknowledgement of the data source if they are used in any publication. The online application for access to the Met Office TOVS data includes acceptance of the Met Office Conditions of Use. Please note that the Met Office data sets are available for bona fide academic research only (sorry no undergraduates), on a per person per project basis (i.e. all members on a same project who will be using the data must individually apply for access to the data). If you wish to access the Met Office data for commercial or personal purposes, please contact the Met Office directly.

Your application for accessing the Met Office TOVS data will be processed within a day of receipt and you will receive a confirmation email. Provided your application is complete and fully meets the Met Office conditions, a web account will be activated to allow you access to the Met Office TOVS data directories via your login account from the BADC WWW Browse Archive pages.

Please read the 00README file available under /badc/ukmo-tovs/ directories to guide you through the tree structure and the data directory.

The monthly data files are held at the BADC in the original VMS binary data format, in which the data are encoded into 2-byte integer arrays, in records which contain a single day's data. The simplicity of the data format allows the data to be read on a wide variety of computer platforms with only very minor changes to the access routines.

The monthly means are available in the PP file format.

We have produced a BADC help file for this data set which condenses information from a number of sources. It contains details of the TOVS instruments, the analysis scheme and the data - including resolution, coverage and quality.

In addition we have made available the VMS binary file format specification for the analyses which was adapted from the Met Office Technical Note 24 (Bailey et al., 1992).

This data set is documented in detail in a paper by Bailey et al. (J. Appl. Meteor. 32, pp. 1472-1483, 1993), and the Met Office Climate Research Technical Note No.24.

We also provide a list of other references which give background information on the dataset and results of studies using the analyses.

There are a number of sites on the Worldwide Web which hold information about, or data from the TOVS subsystem of the NOAA/TIROS-N satellites.

If you have queries about these pages or about obtaining the Met Office TOVS analyses from the BADC then you should contact BADC Support

For more information about this dataset, you may contact Richard Swinbank or other members of the Middle Atmosphere Group in the Numerical Weather Prediction Division at the Met Office.