These datasets have been superseded by later versions and are provided here as an archive.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.
Hemispheric and global averages graph (also available as a PostScript file) |
The basic dataset (HadCRUT) is a combination of land air temperature anomalies (Jones, 1994, CRUTEM1) and sea surface temperature anomalies (Parker et al., 1995) on a 5° x 5° grid-box basis. The merging of the two datasets is discussed in Parker et al. (1994) and more recently in Jones et al. (2001). Both components of the dataset are expressed as anomalies from 1961-90, as this makes merging much easier. The dataset has been extensively used in the various IPCC reports (see, e.g., Nicholls et al., 1996). An absolute temperature climatology is also available (details in Jones et al., 1999).
Average hemispheric (Northern, Southern) and global time series (from HadCRUT) are also available.
Annual values for these three series are plotted.
The standard error is due to sampling of the individual annual values since 1951 is
estimated to be 0.05°C (see Jones et al., 1997 for details).
The above two datasets (HadCRUT and CRUTEM1) have been available on this website for several years. Recent work (discussed in Jones et al., 2001) has adjusted the variance of these grid box datasets for the effects of changing numbers of stations / SST observations through time. These three datasets are:
Gridded data ASCII file format |
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for year = startyear to endyear for month = 1 to 12 for row = 1 to 36 (85-90N,80-85N,75-70N,...75-80S,80-85S,85-90S) format(i4,i3,i2,72i6) year,month,field,180W-175W,175W-170W,...,175-180E |
Missing values represented by -9999
Field=1: temperature anomalies wrt 1961-90 °C*100 (except "Absolute" which is mean temperature 1961-90 °C*100 although with only one decimal place of precision) Field=2: number of stations used at each grid box (only in CRUTEM1) |
Hemispheric/global average data file format |
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for year = 1856 to 2001 format(i5,13f7.2) year, 12 * monthly values, annual value (f7.3 for global annual) format(i5,12i7) year, 12 * percentage coverage of hemisphere or globe |
NetCDF format is read by many commercial data-processing packages (eg. IDL) and public-domain software (eg. ncview)
Dataset | gzipped ASCII | NetCDF | gzipped NetCDF | Last updated |
---|---|---|---|---|
CRUTEM1 | crutem1.dat.gz 2.9mb |
crutem1.nc 18.9mb |
crutem1.nc.gz 1.7mb |
2003-01-24 |
HadSST1 | hadsst1.dat.gz 2.9mb |
hadsst1.nc 8.0mb |
hadsst1.nc.gz 2.3mb |
2000-02-18 |
HadCRUT | hadcrut.dat.gz 4.3mb |
hadcrut.nc 9.1mb |
hadcrut.nc.gz 3.3mb |
2003-01-30 |
HadCRUTv | hadcrutv.dat.gz 3.9mb |
hadcrutv.nc 8.0mb |
hadcrutv.nc.gz 3.1mb |
2000-02-18 |
CRUTEM1v | crutem1v.dat.gz 2.2mb |
crutem1v.nc 9.3mb |
crutem1v.nc.gz 1.6mb |
2001-01-26 |
Absolute | absolute.dat.gz 47kb |
absolute.nc 63kb |
absolute.nc.gz 40kb |
1999-07-13 |
Dataset | ASCII | Last updated | Description |
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TaveNH | tavenh.dat 27kb |
2003-01-30 | Northern Hemisphere average temp. 1856 to 2002 |
TaveSH | tavesh.dat 27kb |
2003-01-30 | Southern Hemisphere average temp. 1856 to 2002 |
TaveGL | tavegl.dat 27kb |
2003-02-02 | Global average temp. 1856 to 2002 |