Since we have been periodically posting updates (e.g. 2009, 2010, 2011, 2012, 2015, 2016) of model output comparisons to observations across a range of variables, we have now set up this page as a permanent placeholder for the most up-to-date comparisons. We include surface temperature projections from 1981, 1988, CMIP3, CMIP5, and satellite products (MSU) from CMIP5, and we will update this on an annual basis, or as new observational products become available. For each comparison, we note the last update date.
Global mean surface temperature anomalies
Hansen et al (1981)
Hansen et al (1988)
Original discussion (2007). Scenarios from Hansen et al. (1988). Observations are the GISTEMP LOTI annual figures. Trends from 1984: GISTEMP: 0.19ºC/dec, Scenarios A, B, C: 0.33, 0.28, 0.17ºC respectively (all 95% CI ~±0.02). Last updated: 8th April 2017.
CMIP3 (circa 2004)
Last discussion (2015). Model spread is the 95% envelope of global mean surface temperature anomalies from all individual CMIP3 simulations (using the SRES A1B projection post-2000). Observations are the standard quasi-global estimates of anomalies with no adjustment for spatial coverage or the use of SST instead of SAT over the open ocean. Last updated Feb 2017.
CMIP5 (circa 2011)
Last discussion (2015). Model spread is the 95% envelope of true global mean surface temperature anomalies from all CMIP5 historical simulations (using the RCP4.5 projection post-2005). Forcing adjustment is updated from Schmidt et al. (2014). Observations are the standard quasi-global estimates of anomalies with no adjustment for spatial coverage or the use of SST instead of SAT over the open ocean. Last updated Feb 2017.
Satellite-derived atmospheric temperatures
MSU-TMT (global and tropical means) (timeseries and trends)
Original discussion (Jan 2017). Mid-troposphere satellite products from UAH, RSS, NOAA STAR and UW. Model values use synthetic MSU-TMT weightings, spread is 95% envelope of simulations. Last updated Mar 2017.
If you have suggestions for additional comparisons, stylistic changes, clarifications etc., please leave a comment here, or on the latest open thread. You can use these figures anywhere (with citation and link back to RealClimate).
- J. Hansen, D. Johnson, A. Lacis, S. Lebedeff, P. Lee, D. Rind, and G. Russell, "Climate Impact of Increasing Atmospheric Carbon Dioxide", Science, vol. 213, pp. 957-966, 1981. http://dx.doi.org/10.1126/science.213.4511.957
- J. Hansen, I. Fung, A. Lacis, D. Rind, S. Lebedeff, R. Ruedy, G. Russell, and P. Stone, "Global climate changes as forecast by Goddard Institute for Space Studies three-dimensional model", Journal of Geophysical Research, vol. 93, pp. 9341, 1988. http://dx.doi.org/10.1029/JD093iD08p09341
- G.A. Schmidt, D.T. Shindell, and K. Tsigaridis, "Reconciling warming trends", Nature Geoscience, vol. 7, pp. 158-160, 2014. http://dx.doi.org/10.1038/ngeo2105