UEA ENV Climatic Research Unit Climate Data

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NCEP/NCAR Reanalysis 1: European Window

The reanalysis data are available for numerous meteorological parameters, as 6-hourly observations, and daily and monthly averages. They generally extend back from the present day to 1948, and cover the entire globe. For a full description of the project which sourced this data, please visit the NCEP/NCAR Reanalysis 1 Home Page.

The source data were provided by the Physical Sciences Laboratory, who provide a full description of the data. Please credit them if you use this data! Follow the 'description' link for details.

The work done at CRU has extracted spatial subsets of the data, and reformatted from netCDF to plain ASCII. All enquiries about the validity of the data, or its development, should be addressed to the PSL or to the contact at the foot of the dataset page above.

Only daily and 6-hourly data sets are referenced here, for a Quarter-Spherical window covering Eastern America and West/central Eurasia.

File format
  • All files (apart from the land/sea masks) are compressed with gzip.
  • Daily and 6-Hourly files are in ASCII text format, space-separated, with a field width of 12 characters.
  • Each file contains vertically-concatenated grids of values, each grid being a set of values for a particular time step.
  • Each line represents a latitude step; each column a longitude step. The first line represents the northernmost latitude.
  • The extraction window is 90°N - 0°N; 90°W - 90°E.  Since Surface Flux data are on Gaussian grids, the exact window sizes are sometimes non-integer. Always see the appropriate Read_me file for exact details.
  • The filename includes the dimensions of a single grid.
  • An example filename, for air temperature, would be air.2m.gauss.1958.d.qs_eurasia.97x48.dat:

VariableTypeDaily Folders6-Hourly Folders
Air Temperature at SurfaceSurfacedaily6-hourly
Air Temperature at 2m (problem report)Surface Fluxdaily6-hourly
Maximum Air Temperature at 2m (problem report)Surface Fluxdaily6-hourly
Minimum Air Temperature at 2m (problem report)Surface Fluxdaily6-hourly
Air TemperaturePressure Levelsdaily6-hourly
Geopotential HeightPressure Levelsdaily6-hourly
Precipitation RateSurface Fluxdaily6-hourly
Precipitable WaterSurface (see note)daily6-hourly
Relative HumidityPressure Levelsdaily6-hourly
Specific Humidity at 2mSurface Fluxdaily6-hourly
Specific HumidityPressure Levelsdaily6-hourly
Sea Level Pressure (problem report)Surfacedaily6-hourly
U-Wind ComponentPressure Levelsdaily6-hourly
U-Wind ComponentSurfacedaily6-hourly
U-Wind Component at 10mSurface Fluxdaily6-hourly
V-Wind ComponentPressure Levelsdaily6-hourly
V-Wind ComponentSurfacedaily6-hourly
V-Wind Component at 10mSurface Fluxdaily6-hourly
Land/Sea MasksFiles
Mask for Surface and Pressure Level Datalsmask.qs_eurasia.73x37.dat
Mask for Surface Flux Datalsmask.gauss.qs_eurasia.97x48.dat

Note: Precipitable Water, although classed as a Surface parameter, applies to the entire atmospheric column (hence, 'eatm' in the filenames).


These datasets are made available under the Open Database License. Any rights in individual contents of the datasets are licensed under the Database Contents License under the conditions of Attribution and Share-Alike.

Please use the attribution Climatic Research Unit, University of East Anglia

Updated: November 2023, Ian Harris