This dataset contains atmospheric nitrous acid (HONO) combined measurements made at the Institute of Atmospheric Physics land station (IAP-Beijing) site, during the summer and winter APHH-Beijing campaign for the Atmospheric Pollution & Human Health in a Chinese Megacity (APHH) programme. This combined dataset consists of a single mean time series of HONO mixing ratio (ppb), and associated min/max values determined from the datasets of 4 instruments that measured HONO at IAP at ground level. The data are averaged over 1 hour, the time stamp represents the start time of each averaging period. The instruments included in the combined dataset are the University of Birmingham commercial wet-chemical LOPAP instrument (Heland et al. 2001), Institute of Chemistry, Chinese Academy of Sciences custom built wet-chemical instrument (Tong et al. 2016), and two custom built Broadband Cavity Enhanced Spectrophotmeters (BBCEAS) from the University of Cambridge (Kennedy et al. 2011) and Anhui Institute of Optics and Fine Mechanics (Duan et al. 2018).

This dataset contains air sample measurements of isotopic d13C methane. The measurements were collected using regular flask samples at Royal Holloway Earth Sciences Monitoring Station, UK at Royal Holloway University of London. The samples were analysed Royal Holloway University of London using continuous flow gas chromatography/isotope ratio mass spectrometry (CF-GC/IRMS). These data were collected as part of the Methane Observations and Yearly Assessments (MOYA) project funded by the Natural Environment Research Council (NERC) (NE/N016211/1).

The UK daily temperature data contain maximum and minimum temperatures (air, grass and concrete slab) measured over a period of up to 24 hours. The measurements were recorded by observation stations operated by the Met Office across the UK and transmitted within NCM, DLY3208 or AWSDLY messages. The data span from 1853 to 2020. For details on measurement techniques, including calibration information and changes in measurements, see section 5.2 of the MIDAS User Guide linked to from this record. Soil temperature data may be found in the UK soil temperature datasets linked from this record. This version supersedes the previous version of this dataset and a change log is available in the archive, and in the linked documentation for this record, detailing the differences between this version and the previous version. The change logs detail new, replaced and removed data. Of particular note, however, is that as well as including data for 2020, historical data recovery has added further data for Eskdalemuir (1915-1948) and Eastbourne (1887-1910). This dataset is part of the Midas-open dataset collection made available by the Met Office under the UK Open Government Licence, containing only UK mainland land surface observations owned or operated by the Met Office. It is a subset of the fuller, restricted Met Office Integrated Data Archive System (MIDAS) Land and Marine Surface Stations dataset, also available through the Centre for Environmental Data Analysis - see the related dataset section on this record. Currently this represents approximately 95% of available daily temperature observations within the full MIDAS collection.

This dataset contains voltage data taken from the Canadian Riometer Array (CRA). The provided tables and datasets can be used to determine if the voltage time series of CRA riometers have characteristic spectral features. In addition, datasets are provided which have been collected from the Solar Wind Electron Proton Monitor (SWEPAM) and Magnetic Field Experiment (MAG) instruments aboard the Atmospheric Composition Explorer (ACE).

The UK daily weather observation data contain meteorological values measured on a 24 hour time scale. The measurements of sunshine duration, concrete state, snow depth, fresh snow depth, and days of snow, hail, thunder and gail were attained by observation stations operated by the Met Office across the UK operated and transmitted within DLY3208, NCM, AWSDLY and SYNOP messages. The data span from 1889 to 2019. For details of observations see the relevant sections of the MIDAS User Guide linked from this record for the various message types. This version supersedes the previous version of this dataset and a change log is available in the archive, and in the linked documentation for this record, detailing the differences between this version and the previous version. The change logs detail new, replaced and removed data. Of particular note, however, is that as well as including data for 2019, historical data recovery has added temperature and weather data for Bude (1937-1958), Teignmouth (1912-1930), and Eskdalemuir (1915-1948). This dataset is part of the Midas-open dataset collection made available by the Met Office under the UK Open Government Licence, containing only UK mainland land surface observations owned or operated by the Met Office. It is a subset of the fuller, restricted Met Office Integrated Data Archive System (MIDAS) Land and Marine Surface Stations dataset, also available through the Centre for Environmental Data Analysis - see the related dataset section on this record. Currently this represents approximately 95% of available daily weather observations within the full MIDAS collection.

This dataset contains air sample measurements of isotopic d13C methane. The measurements were collected using regular flask samples on the Llanos de Moxos wetland near Trinidad, Bolivia. The samples were analysed Royal Holloway University of London using continuous flow gas chromatography/isotope ratio mass spectrometry (CF-GC/IRMS). These data were collected as part of the Methane Observations and Yearly Assessments (MOYA) project funded by the Natural Environment Research Council (NERC) (NE/N016211/1).

The UK hourly solar radiation data contain the amount of solar irradiance received during the hour ending at the specified time. All sites report 'global' radiation amounts. This is also known as 'total sky radiation' as it includes both direct solar irradiance and 'diffuse' irradiance as a result of light scattering. Some sites also provide separate diffuse and direct irradiation amounts, depending on the instrumentation at the site. For these the sun's path is tracked with two pyrometers - one where the path to the sun is blocked by a suitable disc to allow the scattered sunlight to be measured to give the diffuse measurement, while the other has a tube pointing at the sun to measure direct solar irradiance whilst blanking out scattered sun light. This version supersedes the previous version of this dataset and a change log is available in the archive, and in the linked documentation for this record, detailing the differences between this version and the previous version. The change logs detail new, replaced and removed data. The data were collected by observation stations operated by the Met Office across the UK and transmitted within the following message types: SYNOP, HCM, AWSHRLY, MODLERAD, ESAWRADT and DRADR35 messages. The data spans from 1947 to 2018. This dataset is part of the Midas-open dataset collection made available by the Met Office under the UK Open Government Licence, containing only UK mainland land surface observations owned or operated by the Met Office. It is a subset of the fuller, restricted Met Office Integrated Data Archive System (MIDAS) Land and Marine Surface Stations dataset, also available through the Centre for Environmental Data Analysis - see the related dataset section on this record.

This dataset contains summary 3-year time-integrated data of the global mean volcanic stratospheric aerosol optical depth, effective radiative forcing and anomalous deposited sulfate on Antarctica and Greenland. The data are from 82 model simulations of volcanic eruptions that have different sulfur dioxide emissions, eruption latitudes and emission altitudes. Two ensembles were conducted for eruptions starting in January and July. Each simulation was run for ~3 years in a year 2000 timeslice condition. The simulations are from the Unified Model coupled with the United Kingdom Chemistry and Aerosol Scheme (UM-UKCA) and were conducted at a global resolution of 1.875 ° x 1.25°. This data were collected as part of the NERC Reconciling Volcanic Forcing and Climate Records throughout the Last Millennium (Vol-Clim) project. V3 is the latest data file to use.

This dataset contains air sample measurements of isotopic d13C methane. The measurements were collected using regular flask samples at Jersey Radar Station, UK. The samples were analysed Royal Holloway University of London using continuous flow gas chromatography/isotope ratio mass spectrometry (CF-GC/IRMS). These data were collected as part of the Methane Observations and Yearly Assessments (MOYA) project funded by the Natural Environment Research Council (NERC) (NE/N016211/1).

The UK daily temperature data contain maximum and minimum temperatures (air, grass and concrete slab) measured over a period of up to 24 hours. The measurements were recorded by observation stations operated by the Met Office across the UK and transmitted within NCM, DLY3208 or AWSDLY messages. The data span from 1853 to 2018. For details on measurement techniques, including calibration information and changes in measurements, see section 5.2 of the MIDAS User Guide linked to from this record. Soil temperature data may be found in the UK soil temperature datasets linked from this record. This version supersedes the previous version of this dataset and a change log is available in the archive, and in the linked documentation for this record, detailing the differences between this version and the previous version. The change logs detail new, replaced and removed data. This dataset is part of the Midas-open dataset collection made available by the Met Office under the UK Open Government Licence, containing only UK mainland land surface observations owned or operated by the Met Office. It is a subset of the fuller, restricted Met Office Integrated Data Archive System (MIDAS) Land and Marine Surface Stations dataset, also available through the Centre for Environmental Data Analysis - see the related dataset section on this record. Currently this represents approximately 95% of available daily temperature observations within the full MIDAS collection.