Climatic Research Unit : Data : Temperature
Land Stations used by the Climatic Research Unit within CRUTEM4
These datasets have been superseded by later versions and are provided here as an archive. To obtain the current versions
of these datasets, go to the CRU temperature data page.
Two files are provided here, each containing a list of the station
locations and names used in the gridding that is used to produce CRUTEM4.
All these stations have sufficient data to estimate 30-year averages for 1961-90 as defined in Jones et al. (2012) or
have estimates of these averages from other sources.
They each have data for at least some, but not necessarily all, of the dataset period (1850-present).
In each file there are five pieces of information:
- World Meteorological Organization (WMO) Identification Number (ID)
The WMO maintains a list of station numbers for meteorological stations to facilitate international data exchange. Unfortunately, many countries also maintain their own numbering systems and station lists for a range of operational and historical reasons. Occasionally, stations do not have a matching WMO number or have inconsistent WMO numbers.
The numbers we use are listed in numerical order up to station number 988360. Up to this point, the numbers ending in zeroes are generally the WMO number (*10) in use for that station in the mid-1980s, however, WMO numbers can change and we endeavour to mirror such changes. Numbers not ending in a zero have generally been assigned by CRU or may have originated from other sources.
Latitude of the station in degrees and tenths (so 712 is 71.2 degrees N). Positive values are degrees and tenths North, with negative values for the Southern Hemisphere.
Longitude of the station in degrees and tenths (as with the latitude). Positive values are West and negative East (NB this is opposite to the more usual convention). These longitudes refer to the locations of the stations as defined in the mid-1980s, although some may have been updated in the 2000s.
Station elevation (in metres). Unknown elevations are coded as -999.
- Name and Country
The final field is the station name and the country.
The remaining fields indicate the first and last year with data, the source code and the first year considered to contain reliable data.
The CRUTEM4.0 file contains two further numbers for internal use during the gridding process.
Note that the format of the two files differs.
Some other considerations when using these files
The gridding process used in Jones et al.. (2012) and earlier publications assigns each station to the 5 degree latitude/longitude box within which it is located. The gridding then simply averages all available station temperatures (as anomalies from 1961-90) within each grid box for each month from 1850. No account is taken of the station's elevation or location within the grid box (anomalies show little consistent dependence on altitude).
Jones, P.D., Lister, D.H., Osborn, T.J., Harpham, C., Salmon, M. and Morice, C. 2012:
Hemispheric and large-scale land-surface air temperature variations: An extensive revision and an update to 2012.
J. Geophys. Res. 117, D05127, doi:10.1029/2011JD017139.