Plots of raw backscatter profiles from the MST Radar Facility's Vaisala LD40 laser ceilometer, Capel Dewi, Wales obtained during the Icelandic Volcano, Eyjafjallajokull, erupting from on 14th April 2010. The volcanic ash cloud produced covered much of Northern Europe for several weeks causing extensive disruption to air travel. The UK and European atmospheric communities had many instruments - both airborne and ground-based, remote sensing and in-situ - taking measurements of the ash cloud throughout this period.

Version 0 processing of data from the Natural Environment Research Council's (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar near Aberystwyth in West Wales represents processing scheme in place from the early 1990s until 2007. The principal measurements made by the MST radar are of the three dimensional wind vector over the altitude range 2 - 20 km, with additional measurements from the mesophere between 65 and 80 km. The data in this dataset include echo power as well as radial and vector winds components. Surface meteorological measurements from the radar site, ceilometer data, sky camera images and wind speed and direction recorded from a 10m tower located 6km away are also available. Other instruments at the facility have included one of the Met Office's boundary layer wind profilers and NCAS's boundary layer wind profiler.

Version 2 processing of data from the Natural Environment Research Council's (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar near Aberystwyth in West Wales. The principal measurements made by the MST radar are of the three dimensional wind vector over the altitude range 2 - 20 km, with additional measurements from the mesosphere between 65 and 80 km. These data include both the radial beam data plus the resulting Cartesian products. Surface meteorological measurements from the radar site, ceilometer data, sky camera images and wind speed and direction recorded from a 10m tower located 6km away are also available. Other instruments at the facility have included one of the Met Office's boundary layer wind profilers and NCAS's boundary layer wind profiler.

The Natural Environment Research Council (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar is operated by the Science and Technology Facilities Council at the Radar Facility's (MSTRF's) site in Capel Dewi, near Aberystwyth, Mid-Wales. The 46.5 MHz pulsed Doppler radar is used primarily for making atmospheric observations over the approximate altitude range 2 - 20 km, i.e. over most of the troposphere and the lower stratosphere - hence the term "ST-mode". Additional observations are made over the approximate altitude range 56 - 96 km, i.e. covering the mesosphere - hence the term "M-mode" (see related dataset). The instrument has been in operation, using the Dopppler Beam Swinging technique (see linked documentation for further details), since late 1989. It was intially operated on a campaign basis, but switched to quasi-continuous observations (i.e. close to 24-7 operation) in late 1997. This dataset includes radial data products, i.e. range profiles along each beam pointing direction, and the "Cartesian" data products that are derived from them in the form of altitude profiles. The latter are used for most purposes. Data products are derived from the version 3 processing scheme, which supersedes earlier versions. Further details can be found via the linked documentation. Radial data products include: signal power (relates to atmospheric structure) radial velocity (relates to wind speed along the beam pointing direction) spectral width (relates to turbulence intensity) Cartesian data products include: horizontal wind components (zonal and meridional) vertical wind velocity vertical beam signal power tropopause altitude vertical beam spectral width radar return aspect sensitivity

Data from the instruments at the Natural Environment Research Council (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar Facility near Aberystwyth in West Wales. The principal measurements made by the MST radar are of the three dimensional wind vector over the altitude range 2 - 20 km. Surface meteorological measurements from the radar site, ceilometer data, sky camera images and wind speed and direction recorded from a 10m tower located 6km away are also available. Other instruments at the facility have included one of the Met Office's boundary layer wind profilers and NCAS's boundary layer wind profiler.

Version 1 processing of data from the Natural Environment Research Council's (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar near Aberystwyth in West Wales. The principal measurements made by the MST radar are of the three dimensional wind vector over the altitude range 2 - 20 km, with additional measurements from the mesosphere between 65 and 80 km. These data include both the radial beam data plus the resulting Cartesian products. Surface meteorological measurements from the radar site, ceilometer data, sky camera images and wind speed and direction recorded from a 10m tower located 6km away are also available. Other instruments at the facility have included one of the Met Office's boundary layer wind profilers and NCAS's boundary layer wind profiler.

The Natural Environment Research Council (NERC) Mesosphere-Stratosphere-Troposphere (MST) Radar is operated by the Science and Technology Facilities Council at the Radar Facility's (MSTRF's) site in Capel Dewi, near Aberystwyth, Mid-Wales. The 46.5 MHz pulsed Doppler radar is used primarily for making atmospheric observations over the approximate altitude range 2 - 20 km, i.e. over most of the troposphere and the lower stratosphere - hence the term "ST-mode". Additional observations are made over the approximate altitude range 56 - 96 km, i.e. covering the mesosphere - hence the term "M-mode" (see related dataset). The instrument has been in operation, using the Dopppler Beam Swinging technique (see linked documentation for further details), since late 1989. It was intially operated on a campaign basis, but switched to quasi-continuous observations (i.e. close to 24-7 operation) in late 1997. This dataset includes radial data products, i.e. range profiles along each beam pointing direction, and the "Cartesian" data products that are derived from them in the form of altitude profiles. The latter are used for most purposes. Data products are derived from the version 3 processing scheme, which supersedes earlier versions. Further details can be found via the linked documentation. Radial data products include: signal power (relates to atmospheric structure) radial velocity (relates to wind speed along the beam pointing direction) spectral width (relates to turbulence intensity) Cartesian data products include: horizontal wind components (zonal and meridional) vertical wind velocity vertical beam signal power tropopause altitude vertical beam spectral width radar return aspect sensitivity 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.

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.