This dataset holds Northern Hemisphere (north of 15 deg. N) daily and monthly series of 500 hPa geopotential height fields and also daily and monthly series of 1000-500 hPa thickness fields. The data is gridded (5x10 grid). The data is available for the period 1945 to 2005. The data is supplied by the Met Office, Hadley Centre.

The fully Global Mean Sea-Level Pressure (GMSLP) dataset, was developed in collaboration with CSIRO (Scientific and Industrial Research for Australia), Australia and NIWA (National Institute of Water and Atmospheric Research), New Zealand. It is an historical, 5 deg. x 5 deg. gridded monthly dataset covering the period 1871-1994. The Met Office Hadley Centre recently produced the HadSLP1 dataset which replaces the Global Mean Sea Level Pressure (GMSLP) data sets, and is a unique combination of monthly globally-complete fields of land and sea pressure observations a 5 degree latitude-longitude grid from 1871 to 1998.

The longest available instrumental record of temperature in the world is now available from CEDA-BADC. The monthly series of temperature begins in 1659 and the daily data starts in 1772. Seasonal series are also available. The mean, minimum and maximum datasets are updated monthly, with data for a month usually available by the 3rd of the next month. A provisional CET value for the current month is calculated on a daily basis. The mean daily data series begins in 1772 and the mean monthly data in 1659. Mean maximum and minimum daily and monthly data are also available, beginning in 1878. These historical temperature series are representative of the Midlands region in England, UK (a roughly triangular area of the United Kingdom enclosed by Bristol, Lancashire and London). Manley (1953,1974) compiled most of the monthly series, covering 1659 to 1973. These data were updated to 1991 by Parker et al (1992), when they calculated the daily series. Both series are now kept up to date by the Climate Data Monitoring section of the Hadley Centre, Met Office. Since 1974 the data have been adjusted by 0.1-0.3 degree C to allow for urban warming. The Met Office have also been compiling Maximum, Minimum and Mean Daily Central England Temperatures data files since January 1878. The following stations are used by the Met Office to compile the CET data: Rothamsted, Malvern, Squires Gate and Ringway. But in November 2004, the weather station Stonyhurst replaced Ringway and revised urban warming and bias adjustments have now been applied to the Stonyhurst data after a period of reduced reliability from the station in the summer months. The data set is compiled by the Met Office Hadley Centre.

The HadAT1 data are global radiosonde gridded temperature anomalies at standard levels (850, 700, 500, 300, 200, 150, 100, 50, and 30hPa) in the troposphere and in the lower stratosphere from 1958 to December 2002. This monthly timeseries are available on a 10 degree longitude by 5 degree latitude basis. This dataset supersedes the HadRT dataset. All values are anomalies relative to the monthly 1966-95 climatology.

The HADRT2.0 (unadjusted) data are global monthly fields of radiosonde temperature anomalies at standard pressure levels on a 5 degree latitude by 10 degree longitude grid from 1958 to July 2004. Anomalies are calculated with respect to 1971-1990 climatology. Anomalies are available for 9 standard levels (850, 700, 500, 300, 200, 150, 100, 50, 30hPa) as well as tropospheric (850 - 300hPa) and stratospheric (150 - 30hPa) averages. The data are degree Celsius anomalies from 1970-1990 means. Anomalies are calculated for each of about 200 sonde stations worldwide and grid values derived from these. This dataset has been superseded by the HadAT dataset also available from CEDA.

The HadAT2 data are global radiosonde gridded temperature anomalies at standard levels (850, 700, 500, 300, 200, 150, 100, 50, and 30hPa) in the troposphere and in the lower stratosphere from 1958 to December 2012. This monthly timeseries are available on a 10 degree longitude by 5 degree latitude basis. This dataset supersedes the HadRT dataset. All values are anomalies relative to the monthly 1966-95 climatology.

MOHSST, (Met Office Historical Sea-Surface Temperature) is a gridded dataset of sea-surface temperature anomalies covering the period 1856-2006. MOHSST has now been superceeded by HadSST2. We now recommend use of HadSST2 instead of MOHSST for all purposes. MOHSST is only still available in case it is needed for direct comparison with earlier work where MOHSST was used. MOHSST is produced by taking in-situ measurements of SST from ships and buoys, rejecting measurements which which fail quality checks, converting the measurements to anomalies by subtracting climatological values from the measurements, and averaging the resulting anomalies on a 5 by 5 degree monthly grid. Up to 1996 the measurements used are those in the U.K. Marine Data Bank; more recent years use data coming in through the GTS. After gridding the anomalies, bias corrections are applied to remove spurious trends caused by changes in SST measuring practices, and the data are smoothed to reduce noise. The data were provided by the Met Office Hadley Centre.

The HADRT2.3 data are global monthly fields of radiosonde temperature anomalies at standard pressure levels on a 5 degree latitude by 10 degree longitude grid from 1958 to 2000. Anomalies are calculated with respect to 1971-1990 climatology. Anomalies are available for 9 standard levels (850, 700, 500, 300, 200, 150, 100, 50, 30hPa) as well as tropospheric (850 - 300hPa) and stratospheric (150 - 30hPa) averages. The data are degree Celsius anomalies from 1970-1990 means. Anomalies are calculated for each of about 200 sonde stations worldwide and grid values derived from these. HADRT2.3 is a globally complete dataset based on HadRT2.1 1958-2000, but with gaps filled in by reference to the second derivative of the corresponding NCEP reanalysis temperature fields, using the Laplacian technique of Reynolds, 1988: A Real-Time Global Sea Surface Temperature Analysis. J. Climate (see docs for a link to this publication) This dataset has been superseded by the HadAT dataset also available from CEDA.

CRUTEM4 is a gridded dataset of global historical near-surface air temperature anomalies over land. This specific version is CRUTEM4.2.0.0-2013-03, available for each month from January 1850 to March 2013, on a 5 degree grid. Hemispheric and global anomaly series are provided. The dataset is a collaborative product of the Climatic Research Unit at the University of East Anglia and the Met Office Hadley Centre. The CRUTEM4 dataset is updated on a monthly basis; these updates are available from the institutions listed below (see Links).

MOHMAT, (Met Office Historical Marine Air Temperature) is a gridded dataset of marine air temperature anomalies covering the period 1856-2006. The current version of the dataset is MOHMAT4, which is described in reference below (under Doc tab). MOHMAT is produced by taking in-situ measurements of MAT from ships and buoys, rejecting measurements which fail quality checks, converting the measurements to anomalies by subtracting climatological values from the measurements, and averaging the resulting anomalies on a 5 by 5 degree monthly grid. Note that only night-time data are used, because day-time data are corrupted by heat island effects. Up to 1996 the measurements used are those in the U.K. Marine Data Bank; more recent years use data coming in through the GTS. MOHMAT is no longer updated. After gridding the anomalies, bias corrections are applied to remove spurious trends caused by changes in ship deck heights and various unusual operational practices, and the data are smoothed to reduce noise. The data are provided by the Met Office.