The Natural Environment Research Council (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar is operated by the Science and Technology Facilities Council (STFC) at the Radar Facility's (MSTRF's) site in Capel Dewi, near Aberystwyth, Mid-Wales.

This dataset contains time-series of vertical profiles of derived atmospheric dynamics (wind speed, direction) and structure (indications of refractive index structures and turbulence) from observations taken from the 46.5 MHz pulsed Doppler radar. It is primarily used for making atmospheric observations over the approximate altitude range 2 - 20 km, i.e. of the free troposphere (above the boundary layer) and the lower stratosphere, known as the "ST-mode". Additional observations are made over the approximate altitude range 56 - 96 km, i.e. covering the mesosphere - known as the "M-mode" (see related dataset); hence the term "MST" radar.

The instrument has been in operation, using the Doppler Beam Swinging technique (see linked documentation for further details), since late 1989. It was initially operated on a campaign basis, but switched to quasi-continuous observations (i.e. close to 24-7 operation) in late 1997. In 2011 the radar system underwent renovation with significant improvements in radar performance.

The version 4.0 (v4.0) data processing scheme is closely related to the version 3 (v3) scheme and uses v3 Cartesian files as input. The main difference is that the horizontal wind components in the v4 Cardinal files represent time averages, which have a smaller random measurement error compared to the single cycle estimates in the v3 Cartesian files.

Data products available from the v4 Cardinal files include time-series profiles of:
- eastward wind
- northward wind
- upward wind
- (radar return) signal power (giving an indication of atmospheric structure) - also known as echo power
- (beam broadening) corrected spectral width (giving a measure of turbulence intensity)
- tropopause altitude and sharpness

A full list of variables will be added to this record in due course.

Quick look plots for these data are available - see related links under the "docs" tab below.

Note - some files are released marked as '-suspect'. These have been released to permit early access to the data where the majority of data are known to pass quality control, but a small, limited part of the data have been identified as being 'suspect'. An internal remark about the suspect data may be found within the file's metadata 'comments' attribute.