DOI: 10.5285/0545f37fb7124df381d42468eb63c144
title: HadUK-Grid Gridded Climate Observations on a 25km grid over the UK, v1.2.0.ceda (1836-2022)

description: 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 25 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 2022, 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 This data set supersedes the previous versions of this dataset which also superseded UKCP09 gridded observations.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 v1.2.0.ceda HadUK-Grid datasets are as follows: * Added data for calendar year 2022 * Added newly digitised data for monthly sunshine 1910-1918 * Added Rainfall Rescue version 2 doi:10.5281/zenodo.7554242 * Updated shapefiles used for production of area average statistics https://github.com/ukcp-data/ukcp-spatial-files * Updated controlled vocabulary for metadata assignment https://github.com/ukcp-data/UKCP18_CVs * Updated assignment of timepoint for some periods so that the datetime is the middle of the period (e.g. season) rather than a fixed offset from the period start. * Updated ordering of regions within regional values files. Alphabetical ordering. * Files use netcdf level 4 compression using gzip https://www.unidata.ucar.edu/blogs/developer/entry/netcdf_compression * Net changes to the input station data used to generate this dataset: - Total of 125601744 observations - 122621050 (97.6%) unchanged - 26700 (0.02%) modified for this version - 2953994 (2.35%) added in this version - 16315 (0.01%) deleted from this version * Changes to monthly rainfall 1836-1960 - Total of 4823973 observations - 3315657 (68.7%) unchanged - 21029 (0.4%) modified for this version - 1487287 (30.8%) added in this version - 11155 (0.2%) 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.