This dataset contains momentum budget snow removal experiment model data from Dudh Koshi Valley in the Nepalese Himalaya. The Weather Research and Forecasting (WRF) model was run for two months, July 2013 and January 2014, to investigate the momentum budget components of the winds in the Dudh Koshi Valley. All the permanent snow and ice in the model has been changed to rock. This data was collected as part of the Dynamical drivers of the local wind regime in a Himalayan valley project (NE/L002507/1). The WRF model has been modified to output the momentum budget components. There are four nested domains, of 27 km, 9 km, 3 km and 1 km resolution. The inner 1 km is 130 km by 130 km, centred on 27.98N, 86.76E.

This dataset contains model output data on sulphate aerosols, aerosol size distributions and radiative fluxes produced from experiments that used different values of cloud-water pH. The composition-climate model HadGEM3-UKCA was run over the period 1970 to 2009 to investigate the effect of temporal changes in cloud-water pH on sulphate aerosol formation and the subsequent impact on climate. HadGEM3-UKCA is the climate model configuration of the Met Office Unified Model (UM). Vn7.3 of the UM was used in this study and included a branch to the CLOMAP-Mode aerosol scheme. Model simulations were conducted at a global resolution of 1.875° x 1.25°.

This dataset contains Raman Lidar data from four UK sites in the Met Office Volcanic Ash lidar network for the 15th and 16th October 2017 when ex-hurricane Ophelia passed to the West of the British Isles, bringing dust from the Sahara and smoke from Portuguese forest fires that was observable to the naked eye in the UK. The sites included are Camborne, Rhyl, Watnall, and Loftus. The data files contain profiles for co-polar, cross-polar and Raman backscatter data. The data support the following publication: Osborne, M., Adam, M., Buxmann, J., Sugier, J., Marenco, F., and Haywood, J.: Saharan dust and biomass burning aerosols during ex-hurricane Ophelia: validation of the new UK lidar and sun-photometer network, Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-695.

This dataset contains global retrieval of sulphur dioxide (SO2) column amounts and altitudes derived from the Infrared Atmospheric Sounding Interferometer (IASI) instrument on the METOP-A satellite. The data have been produced by the University of Oxford as part of the NERC Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics (COMET). This dataset has been produced using the Carboni et al. (2012,2016) retrieval algorithm for the Infrared Atmospheric Sounding Interferometer which retrieve column amount and altitude (together with a comprehensive error budget for every pixel) using simultaneously all the IASI channels between 1000–1200 and 1300–1410 cm−1. It has a global coverage and includes the six-month-long Holuhraun eruption, from September 2014 to February 2015, together with other events during the same periods such as: volcanic activity on the Kamchatka peninsula, Etna and Capo verde eruptions, anthropogenic SO2 emissions from China. The data presents the results of the retrieval for every IASI 'plume' pixels (e.g. that result positive to the IASI SO2 detection) including: column amount (in Dobson Unit - DU), altitude (in millibar and successively converted in km using meteorological profile), surface temperature. It also includes quality control parameters and quality flags: for generic use we recommend using data with flag = 1. Quality control parameters available are: degree of freedom, cost function, convergence. These quality control paramenters are also summarized in two 'stricted' and 'relaxed' quality control flags. This dataset also includes location of all IASI pixels in the same orbit (non plume pixel) to allow regridding and comparison with other instruments and models.

This is version v3.3.0.2022f of Met Office Hadley Centre's Integrated Surface Database, HadISD. These data are global sub-daily surface meteorological data. The quality controlled variables in this dataset are: temperature, dewpoint temperature, sea-level pressure, wind speed and direction, cloud data (total, low, mid and high level). Past significant weather and precipitation data are also included, but have not been quality controlled, so their quality and completeness cannot be guaranteed. Quality control flags and data values which have been removed during the quality control process are provided in the qc_flags and flagged_values fields, and ancillary data files show the station listing with a station listing with IDs, names and location information. The data are provided as one NetCDF file per station. Files in the station_data folder station data files have the format "station_code"_HadISD_HadOBS_19310101-20230101_v3.3.1.2022f.nc. The station codes can be found under the docs tab. The station codes file has five columns as follows: 1) station code, 2) station name 3) station latitude 4) station longitude 5) station height. To keep informed about updates, news and announcements follow the HadOBS team on twitter @metofficeHadOBS. For more detailed information e.g bug fixes, routine updates and other exploratory analysis, see the HadISD blog: http://hadisd.blogspot.co.uk/ References: When using the dataset in a paper you must cite the following papers (see Docs for link to the publications) and this dataset (using the "citable as" reference) : Dunn, R. J. H., (2019), HadISD version 3: monthly updates, Hadley Centre Technical Note. Dunn, R. J. H., Willett, K. M., Parker, D. E., and Mitchell, L.: Expanding HadISD: quality-controlled, sub-daily station data from 1931, Geosci. Instrum. Method. Data Syst., 5, 473-491, doi:10.5194/gi-5-473-2016, 2016. Dunn, R. J. H., et al. (2012), HadISD: A Quality Controlled global synoptic report database for selected variables at long-term stations from 1973-2011, Clim. Past, 8, 1649-1679, 2012, doi:10.5194/cp-8-1649-2012 Smith, A., N. Lott, and R. Vose, 2011: The Integrated Surface Database: Recent Developments and Partnerships. Bulletin of the American Meteorological Society, 92, 704–708, doi:10.1175/2011BAMS3015.1 For a homogeneity assessment of HadISD please see this following reference Dunn, R. J. H., K. M. Willett, C. P. Morice, and D. E. Parker. "Pairwise homogeneity assessment of HadISD." Climate of the Past 10, no. 4 (2014): 1501-1522. doi:10.5194/cp-10-1501-2014, 2014.

This dataset contains ERA5 surface level invariant parameter data. ERA5 is the 5th generation reanalysis project from the European Centre for Medium-Range Weather Forecasts (ECWMF) - see linked documentation for further details. This dataset contains a limited selection of all available variables and have been converted to netCDF from the original GRIB files held on the ECMWF system. They have also been translated onto a regular latitude-longitude grid during the extraction process from the ECMWF holdings. For a fuller set of variables please see the linked Copernicus Data Store (CDS) data tool, linked to from this record. Model level analysis and surface analysis and forecast data to complement this dataset are also available. Data from a 10 member ensemble, run at lower spatial and temporal resolution, were also produced to provide an uncertainty estimate for the output from the single high resolution (hourly output at 31 km grid spacing) 'HRES' realisation producing data in this dataset. The ERA5 global atmospheric reanalysis of the covers 1979 to 2 months behind the present month. This follows on from the ERA-15, ERA-40 rand ERA-interim re-analysis projects. An initial release of ERA5 data (ERA5t) is made roughly 5 days behind the present date. These will be subsequently reviewed ahead of being released by ECMWF as quality assured data within 3 months. CEDA holds a 6 month rolling copy of the latest ERA5t data. See related datasets linked to from this record. However, for the period 2000-2006 the initial ERA5 release was found to suffer from stratospheric temperature biases and so new runs to address this issue were performed resulting in the ERA5.1 release (see linked datasets). Note, though, that Simmons et al. 2020 (technical memo 859) report that "ERA5.1 is very close to ERA5 in the lower and middle troposphere." but users of data from this period should read the technical memo 859 for further details.

This monthly ozone climatology dataset was produced from a combination of satellite and ozonesonde data from 1966 to 1993. It was produced following the method described by Fortuin and Langematz (1994) and is used by the radiation code within the ECMWF IFS to generate the output from from ERA-Interim reanalysis model runs (see Dee et al. 2011 for further details). The ozone values are given in ppmv on 36 vertical pressure levels and 19 latitudinal bands. These are then internally interpolated to the grid used by the model before entering the radiation scheme. The 19 latitudinal bands the data are present are at: -90, -80, -70, -60, -50, -40, -30, -20, -10, 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 degrees. The climatology was originally produced by Fortuin and Langematz (1994) in response to the many GCMs at that time that used a prescribed ozone field. The aim was to generate a reference field with the required spatial and temporal coverage for use within modelling studies.

HadUK-Grid is a collection of gridded climate variables derived from the network of UK land surface observations. The data have been interpolated from meteorological station data onto a uniform grid to provide complete and consistent coverage across the UK. The dataset at 5 km resolution is derived from the associated 1 km x 1 km resolution to allow for comparison to data from UKCP18 climate projections. The dataset spans the period from 1836 to 2021, but the start time is dependent on climate variable and temporal resolution. The gridded data are produced for daily, monthly, seasonal and annual timescales, as well as long term averages for a set of climatological reference periods. Variables include air temperature (maximum, minimum and mean), precipitation, sunshine, mean sea level pressure, wind speed, relative humidity, vapour pressure, days of snow lying, and days of ground frost. This data set supersedes the previous versions of this dataset which also superseded UKCP09 gridded observations. Subsequent versions may be released in due course and will follow the version numbering as outlined by Hollis et al. (2018, see linked documentation). The changes for v1.1.0.0 HadUK-Grid datasets are as follows: * The addition of data for calendar year 2021 * The addition of 30 year averages for the new reference period 1991-2020 * An update to 30 year averages for 1961-1990 and 1981-2010. This is an order of operation change. In this version 30 year averages have been calculated from the underlying monthly/seasonal/annual grids (grid-then-average) in previous version they were grids of interpolated station average (average-then-grid). This order of operation change results in small differences to the values, but provides improved consistency with the monthly/seasonal/annual series grids. However this order of operation change means that 1961-1990 averages are not included for sfcWind or snowlying variables due to the start date for these variables being 1969 and 1971 respectively. * A substantial new collection of monthly rainfall data have been added for the period before 1960. These data originate from the rainfall rescue project (Hawkins et al. 2022) and this source now accounts for 84% of pre-1960 monthly rainfall data, and the monthly rainfall series has been extended back to 1836. Net changes to the input station data used to generate this dataset: -Total of 122664065 observations -118464870 (96.5%) unchanged -4821 (0.004%) modified for this version -4194374 (3.4%) added in this version -5887 (0.005%) deleted from this version The primary purpose of these data are to facilitate monitoring of UK climate and research into climate change, impacts and adaptation. The datasets have been created by the Met Office with financial support from the Department for Business, Energy and Industrial Strategy (BEIS) and Department for Environment, Food and Rural Affairs (DEFRA) in order to support the Public Weather Service Customer Group (PWSCG), the Hadley Centre Climate Programme, and the UK Climate Projections (UKCP18) project. The output from a number of data recovery activities relating to 19th and early 20th Century data have been used in the creation of this dataset, these activities were supported by: the Met Office Hadley Centre Climate Programme; the Natural Environment Research Council project "Analysis of historic drought and water scarcity in the UK"; the UK Research & Innovation (UKRI) Strategic Priorities Fund UK Climate Resilience programme; The UK Natural Environment Research Council (NERC) Public Engagement programme; the National Centre for Atmospheric Science; National Centre for Atmospheric Science and the NERC GloSAT project; and the contribution of many thousands of public volunteers. The dataset is provided under Open Government Licence.

HadUK-Grid is a collection of gridded climate variables derived from the network of UK land surface observations. The data have been interpolated from meteorological station data onto a uniform grid to provide complete and consistent coverage across the UK. The dataset at 60 km resolution is derived from the associated 1 km x 1 km resolution to allow for comparison to data from UKCP18 climate projections. The dataset spans the period from 1862 to 2020, but the start time is dependent on climate variable and temporal resolution. The gridded data are produced for daily, monthly, seasonal and annual timescales, as well as long term averages for a set of climatological reference periods. Variables include air temperature (maximum, minimum and mean), precipitation, sunshine, mean sea level pressure, wind speed, relative humidity, vapour pressure, days of snow lying, and days of ground frost. This data set supersedes the previous versions of this dataset which also superseded UKCP09 gridded observations. Subsequent versions may be released in due course and will follow the version numbering as outlined by Hollis et al. (2018, see linked documentation). This release includes data for the calendar year 2020. Ongoing quality checks and data recovery to historical data results in changes to around 0.01% of the observational station data used as input to produce the gridded dataset. A correction to _FillValue assignment in the metadata for seasonal and annual grids has also been applied to be consistent with the rest of the dataset. The primary purpose of these data are to facilitate monitoring of UK climate and research into climate change, impacts and adaptation. The datasets have been created by the Met Office with financial support from the Department for Business, Energy and Industrial Strategy (BEIS) and Department for Environment, Food and Rural Affairs (DEFRA) in order to support the Public Weather Service Customer Group (PWSCG), the Hadley Centre Climate Programme, and the UK Climate Projections (UKCP18) project. The data recovery activity to supplement 19th and early 20th Century data availability has also been funded by the Natural Environment Research Council (NERC grant ref: NE/L01016X/1) project "Analysis of historic drought and water scarcity in the UK". The dataset is provided under Open Government Licence.

These datasets contain total, non-fluorescent and bio-fluorescent aerosol particle concentrations and particle size distributions collected with University of Manchester WIBS-4M an MBS-M spectrometers during the Towards a UK Airborne Bioaerosol Climatology (BIOARC) project. Data was collected at the following ground sites: Cardington Meteorological Research Unit: MBS-M, 11/04/2019 - 09/06/2019 Chilbolton Observatory: WIBS-4D, 14/05/2019 - 14/06/2019 Weybourne Atmospheric Observatory: WIBS-4M, 03/06/2019 - 01/08/2019 Chilbolton Observatory: WIBS-4M, 10/09/2020 - 21/06/2021 Weybourne Atmospheric Observatory: MBS-M, 15/09/2020 - 03/11/2019 Weybourne Atmospheric Observatory: MBS-M, 15/04/2021 - 16/07/2021 NERC reference NE/S002049/1