Global annual temperature anomalies

Fig. 3.5 Global annual temperature anomalies (degrees C), 1850-2008 (relative to the 1961-1990 mean) data from P. D. Jones, T. J. Osborn and K. R. Briffa (Prediction and Research, Climatic Research Unit, School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom) and D. E. Parker (Hadley Centre for Climate, Meteorological Office, Bracknell, Berkshire, United Kingdom).

Increases in global surface temperatures, (a) Time trends reflecting annual and 5-year means. Also shown are dates of large volcanic eruptions and (b) geographic trends based on mean values for the period 2001 to 2005 AD. Temperature anomalies are the temperature differences for a given year or location relative to a base mean value for that year or location. The base period is 1951-1980 AD. Source-. After Hansen, J., et al. (2006). Proceedings of the National Academy of Sciences of the United States of America 103, 14288-14293. (See companion website for color version.)... 

FIGURE 14.58 Global nonurban annual average temperature anomalies for the (a) maximum temperature, (b) minimum temperature, and (c) diurnal range of temperatures from 1950 to 1993 for 4100 stations in both the Northern and Southern Hemispheres (adapted from Easterling et at., 1997). 

This table and graph summarize the trend in annual mean global surface temperature from 1856 to 2004. The values were calculated from mean temperature anomalies by assuming an absolute global mean of 14.00°C, which is the best estimate for the 1961-1990 period. The 95% confidence interval for the annual mean temperature values since 1951 is 0.12°C prior to 1900 this interval is 0.18°C. 

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