About the global temperature timeseries graphs

Analyses available

Global and hemispheric temperature timeseries are available for annual, seasonal and individual months from 1900 to present. Seasonal means are December-February (DJF), March-May (MAM), June-August (JJA) and September-November (SON).

Note that temperature timeseries are presented as anomalies or departures from the 1961-1990 average because temperature anomalies tend to be more consistent throughout wide areas than actual temperatures. Normal values (1961-1990 averages) are provided for the selected variable and region. 1961 to 1990 is the current international standard period for the calculation of climate normals.

Data used

The timeseries analyses use the Climatic Research Unit HadCRUT4 global gridded (5x5 degree resolution) temperature data set (see Morice et al, 2012).

These data are the blended near land surface temperature and sea surface temperature anomalies from the 1961-90 reference period, that have been recently developed by the Climatic Research Unit (CRU) at the University of East Anglia, in conjunction with the Hadley Centre of the UK Met Office. This data are publically available through the Climatic Research Unit website. A list of relevant scientific papers relating to the HadCRUT4 dataset is also provided below.

While considerable amounts of missing data exist, particularly during the early part of the record and for specific regions (eg. poles, interior of southern continents) the data have been shown to adequately represent global and hemispheric area-averaged temperature variability and change (eg. see Morice et al, 2012)

The actual data values used to produce each graph are available via the "Raw dataset" link. The format for these data is:

  <start year><start month><end year><end month>   <mean temperature anomaly (°C)>
      

The "Sorted dataset" link provides the timeseries as a sorted list in order to place recent values in historical context.

Please note that any use of these analyses should be acknowledged to the Bureau of Meteorology and the institutions listed above. Apart from the purposes of study, research, criticism and review, no part of these data may be reproduced, or redistributed for any commercial purposes, or distributed to a third party for such purpose, without written permission from the Director of Meteorology.


Further information

Braganza K., Karoly D.J., Hirst A.C., Mann M.E., Stott P.A., Stouffer R.J., Tett, S.F.B. 2003. Simple indices of global climate variability and change: Part I, variability and correlation structure. Climate Dynamics 20 491-502. DOI: 10.1007/s00382- 002-0286-0.

Brohan, P., J.J. Kennedy, I. Haris, S.F.B. Tett and P.D. Jones, 2006. Uncertainty estimates in regional and global observed temperature changes: a new dataset from 1850. J. Geophysical Research 111, D12106, doi:10.1029/2005JD006548.

Christy, J.R., Parker, D.E., Stendel. M. and Norris, W.B., 2001. Differential trends in tropical sea surface temperature and atmospheric temperatures since 1979. Geophysical Research Letters 28, 183-186.

Folland, C.K., Rayner, N.A., Brown, S.J., Smith, T.M., Shen, S.S.P., Parker, D.E., Macadam, I., Jones, P.D., Jones, R.N., Nicholls, N. and Sexton, D.M.H., 2001a. Global temperature change and its uncertainties since 1861. Geophysical Research Letters 28, 2621-2624.

Folland, C.K., Karl, T.R., Christy, J.R., Clarke, R.A., Gruza, G.V., Jouzel, J., Mann, M.E., Oerlemans, J., Salinger, M.J. and Wang, S.-W., 2001b: Observed climate variability and change. pp. 99-181 In: Climate Change 2001: The Scientific Basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change (Houghton, J.T., Ding, Y., Griggs, D.J., Noguer, M., van der Linden, P.J., Dai, X., Maskell, K. and Johnson, C.A. Eds.). Cambridge University Press, Cambridge, UK, 881pp.

Jones, P.D., Osborn, T.J. and Briffa, K.R., 1997. Estimating sampling errors in large-scale temperature averages. Journal of Climate 10, 2548-2568.

Jones, P.D., New, M., Parker, D.E., Martin, S. and Rigor, I.G., 1999. Surface air temperature and its variations over the last 150 years. Reviews of Geophysics 37, 173-199.

Jones, P.D., Osborn, T.J., Briffa, K.R., Folland, C.K., Horton, B., Alexander, L.V., Parker, D.E. and Rayner, N.A., 2001. Adjusting for sampling density in grid-box land and ocean surface temperature timeseries. Journal of Geophysical Research 106, 3371-3380.

Jones, P.D. and Moberg, A., 2003. Hemispheric and large-scale surface air temperature variations: An extensive revision and an update to 2001. Journal of Climate 16, 206-223.

Morice, C. P., J. J. Kennedy, N. A. Rayner, and P. D. Jones., 2012, Quantifying uncertainties in global and regional temperature change using an ensemble of observational estimates: The HadCRUT4 dataset Journal of Geophysical Research 117, D08101, doi 10.1029/2011JD017187

Parker, D.E., Alexander, L.V. and Kennedy, J., 2004. Global and regional climate in 2003. Weather, 59, 145-152.

Rayner, N.A., Parker, D.E., Horton, E.B., Folland, C.K., Alexander, L.V, Rowell, D.P., Kent, E.C. and Kaplan, A., 2003. Globally complete analyses of sea surface temperature, sea ice and night marine air temperature, 1871-2000. Journal of Geophysical Research 108, 4407, doi 10.1029/2002JD002670