The University of Bath's Ascension Island meteor radar (7.9 S, 14.4 W) is an all-sky VHF (Very High Frequency) meteor radar commercially produced Skiymet system. The system was operational from October 2001 to June 2011, albeit with some gaps in the data coverage, in support of a number of research projects - see linked Project records for further details. Meteor detection and derived wind data from this instrument were collected in support of a number of research projects - see linked Project records for further details. The radar detects radio scatter from the ionised trails of individual meteors drifting with the winds of the upper mesosphere, mesopause and lower thermosphere. A low-gain transmitter antenna is used to provide broad illumination of the sky. An array of five receiver antennas act as an interferometer to determine the azimuth and zenith angles of individual meteor echoes. Doppler measurements from each meteor determine the radial drift velocity and the meteor is assumed to be a passive tracer of atmospheric flow. The radar typically detects of order a few thousand meteors per day. These observations can be used to determine zonal and meridional winds in the mesosphere, mesopause and lower thermosphere at heights of about 80 – 100 km and with height and time resolutions of ~ 3 km and 2 hours. The radar produces daily “meteor position data” data files (mpd files) recording the details of each individual meteor echo. In normal operation a few thousand individual meteors are detected per day. See parameter list for details of available data. Recordings are made for each individual meteor detected allowing measurements of zonal and meridional wind speeds in the mesosphere and lower thermosphere to be obtained. Meteor count rates vary diurnally and with season, but are usually up to a few thousand meteors per day.

The University of Bath have operated a number of meteor radars in the northern and southern hemisphere since around 1999. These commercially produced Skiymet meteor radars are all-sky VHF (Very High Frequency) meteor radar systems. The various instruments have been operated by the University of Bath from October 1999 to present - albeit with some gaps in the data coverage. These were collected in support of a number of research projects - see linked Project records for further details. The Skiymet radar detects radio scatter from the ionised trails of individual meteors drifting with the winds of the upper mesosphere, mesopause and lower thermosphere. A low-gain transmitter antenna is used to provide broad illumination of the sky. An array of five receiver antennas act as an interferometer to determine the azimuth and zenith angles of individual meteor echoes. Doppler measurements from each meteor determine the radial drift velocity and the meteor is assumed to be a passive tracer of atmospheric flow. The radar typically detects of order a few thousand meteors per day. These observations can be used to determine zonal and meridional winds in the mesosphere, mesopause and lower thermosphere at heights of about 80 – 100 km and with height and time resolutions of ~ 3 km and 2 hours. The radar produces daily “meteor position data” data files (mpd files) recording the details of each individual meteor echo. In normal operation a few thousand individual meteors are detected per day. The key data parameters recorded for each meteor echo include: 1. Date and time of the meteor detection 2. Range to the meteor echo point 3. Height of the meteor echo above the ground 4. Radial drift velocity of the meteor echo and its uncertainty 5. Zenith and azimuth angles of the meteor echo 6. Ambiguity levels in the determined zenith and azimuth angles 7. Decay time of the meteor echo 8. Meteor echo power and S/N ratio Recordings are made for each individual meteor detected allowing measurements of zonal and meridional wind speeds in the mesosphere and lower thermosphere to be obtained. Meteor count rates vary diurnally and with season, but are usually up to a few thousand meteors per day.

The University of Bath's meteor radar located at the British Antarctic Survey's Rothera base on Rothera Point, Adelaide Island, Antartica (67.57 S, 68.13 W), is an all-sky VHF (Very High Frequency) meteor radar commercially produced Skiymet system. Meteor detection and derived wind data from this instrument are available from 2005. These were collected in support of a number of research projects - see linked Project records for further details. The radar detects radio scatter from the ionised trails of individual meteors drifting with the winds of the upper mesosphere, mesopause and lower thermosphere. A low-gain transmitter antenna is used to provide broad illumination of the sky. An array of five receiver antennas act as an interferometer to determine the azimuth and zenith angles of individual meteor echoes. Doppler measurements from each meteor determine the radial drift velocity and the meteor is assumed to be a passive tracer of atmospheric flow. The radar typically detects of order a few thousand meteors per day. These observations can be used to determine zonal and meridional winds in the mesosphere, mesopause and lower thermosphere at heights of about 80 – 100 km and with height and time resolutions of ~ 3 km and 2 hours. The radar produces daily “meteor position data” data files (mpd files) recording the details of each individual meteor echo. In normal operation a few thousand individual meteors are detected per day. See parameter list for details of available data. Recordings are made for each individual meteor detected allowing measurements of zonal and meridional wind speeds in the mesosphere and lower thermosphere to be obtained. Meteor count rates vary diurnally and with season, but are usually up to a few thousand meteors per day. Note - there are additional data from 20040728 in the archive. No other data were obtained between that date and the start date for the dataset (20050212). The start date of 20050212 has been chosen in order to avoid potential confusion about missing data prior to that date.

The University of Bath's meteor radar located at the King Edward Point Magnetic Observatory (KEP, 54.2820 S, 36.4930 W) on South Georgia island in the South Atlantic , is an all-sky VHF (Very High Frequency) meteor radar commercially produced Skiymet system. It has been operational since 2016 providing meteor detection and derived wind data in support of the NERC funded South Georgia Wave (SG-WEX) and DRAGON-WEX: The Drake Passage and Southern Ocean Wave Experiments (see linked Project records for further details). The radar detects radio scatter from the ionised trails of individual meteors drifting with the winds of the upper mesosphere, mesopause and lower thermosphere. A low-gain transmitter antenna is used to provide broad illumination of the sky. An array of five receiver antennas act as an interferometer to determine the azimuth and zenith angles of individual meteor echoes. Doppler measurements from each meteor determine the radial drift velocity and the meteor is assumed to be a passive tracer of atmospheric flow. The radar typically detects of order a few thousand meteors per day. These observations can be used to determine zonal and meridional winds in the mesosphere, mesopause and lower thermosphere at heights of about 80 – 100 km and with height and time resolutions of ~ 3 km and 2 hours. The radar produces daily “meteor position data” data files (mpd files) recording the details of each individual meteor echo. In normal operation a few thousand individual meteors are detected per day. See parameter list for details of available data. Recordings are made for each individual meteor detected allowing measurements of zonal and meridional wind speeds in the mesosphere and lower thermosphere to be obtained. Meteor count rates vary diurnally and with season, but are usually up to a few thousand meteors per day.

The University of Bath's meteor radar located at the Esrange Space Centre in Northern Sweden (67.88 N, 21.07E) , is an all-sky VHF (Very High Frequency) meteor radar commercially produced Skiymet system. It was operated by the University of Bath from October 1999 to October 2015 - albeit with some gaps in the data coverage. In October 2015, Esrange took over operation of the radar. Meteor detection and derived wind data from this instrument are available from July 2000 to June 2018. These were collected in support of a number of research projects - see linked Project records for further details. The radar detects radio scatter from the ionised trails of individual meteors drifting with the winds of the upper mesosphere, mesopause and lower thermosphere. A low-gain transmitter antenna is used to provide broad illumination of the sky. An array of five receiver antennas act as an interferometer to determine the azimuth and zenith angles of individual meteor echoes. Doppler measurements from each meteor determine the radial drift velocity and the meteor is assumed to be a passive tracer of atmospheric flow. The radar typically detects of order a few thousand meteors per day. These observations can be used to determine zonal and meridional winds in the mesosphere, mesopause and lower thermosphere at heights of about 80 – 100 km and with height and time resolutions of ~ 3 km and 2 hours. The radar produces daily “meteor position data” data files (mpd files) recording the details of each individual meteor echo. In normal operation a few thousand individual meteors are detected per day. See parameter list for details of available data. Recordings are made for each individual meteor detected allowing measurements of zonal and meridional wind speeds in the mesosphere and lower thermosphere to be obtained. Meteor count rates vary diurnally and with season, but are usually up to a few thousand meteors per day.

The University of Bath's Bear Lake Observatory (BLO) meteor radar (42 N, 114 W), Utah, is an all-sky VHF (Very High Frequency) meteor radar commercially produced Skiymet system. The system has been operational from March 2008, providing meteor detection and derived wind data. Note, however, that there have been with some significant gaps in the data coverage. The data have been produced in support of a number of research projects - see linked Project records for further details. Meteor detection and derived wind data from this instrument are available from July 2000 to June 2018. These were collected in support of a number of research projects - see linked Project records for further details. The radar detects radio scatter from the ionised trails of individual meteors drifting with the winds of the upper mesosphere, mesopause and lower thermosphere. A low-gain transmitter antenna is used to provide broad illumination of the sky. An array of five receiver antennas act as an interferometer to determine the azimuth and zenith angles of individual meteor echoes. Doppler measurements from each meteor determine the radial drift velocity and the meteor is assumed to be a passive tracer of atmospheric flow. The radar typically detects of order a few thousand meteors per day. These observations can be used to determine zonal and meridional winds in the mesosphere, mesopause and lower thermosphere at heights of about 80 – 100 km and with height and time resolutions of ~ 3 km and 2 hours. The radar produces daily “meteor position data” data files (mpd files) recording the details of each individual meteor echo. In normal operation a few thousand individual meteors are detected per day. See parameter list for details of available data. Recordings are made for each individual meteor detected allowing measurements of zonal and meridional wind speeds in the mesosphere and lower thermosphere to be obtained. Meteor count rates vary diurnally and with season, but are usually up to a few thousand meteors per day.

This dataset contains Chemical Ablation Model version 3 (CABMOD3) simulations of metal ablation from meteoroids. This experiment was undertaken as part of Natural Environment Research Council (NERC) First study of the global Nickel and Aluminium Layers in the upper atmosphere (NIALL) project (NE/P001815/1). This project aimed to make the first ever study of Ni and Al chemistry in the mesosphere/lower thermosphere.

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

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 data are from a study investigating ozone (O3) variability in the polar mesosphere and lower thermosphere and uncertainties / biases in satellite ozone profile measurements. The datasets include 1) processed atmospheric datasets derived from O3 observations by the ground-based Ny Ålesund Ozone in the Mesosphere Instrument (NAOMI), an 11.072 GHz ozone radiometer making atmospheric observations from Ny Ålesund, Spitsbergen since 4 July 2017, 2) processed atmospheric datasets derived from selected O3 observations by the SABER satellite instrument, and 3) ancillary atmospheric datasets used for NAOMI retrievals, derived from model (WACCM-D) and reanalysis (MERRA-2) datasets. Supported in part by UK Research and Innovation (UKRI) / Natural Environment Research Council (NERC) Technologies Proof-of-Concept grant reference NE/P003478/1 "Satellite TV-based Ozone and OH Observations using Radiometric Measurements (STO3RM)". MOSAIC instrument testing and deployment was supported by the Royal Society Newton Fund reference NI150103 "The Effect of High Energy Particle Precipitation from Space on the Earth''s Atmosphere". Pekka T. Verronen was supported by Academy of Finland project no. 335555 "ICT-Solutions to Understand Variability of Arctic Climate (ICT-SUNVAC)".