Climate Dynamics

, Volume 40, Issue 5–6, pp 1087–1102 | Cite as

A probabilistic quantification of the anthropogenic component of twentieth century global warming

  • T. M. L. WigleyEmail author
  • B. D. Santer


This paper examines in detail the statement in the 2007 IPCC Fourth Assessment Report that “Most of the observed increase in global average temperatures since the mid-twentieth century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations”. We use a quantitative probabilistic analysis to evaluate this IPCC statement, and discuss the value of the statement in the policy context. For forcing by greenhouse gases (GHGs) only, we show that there is a greater than 90 % probability that the expected warming over 1950–2005 is larger than the total amount (not just “most”) of the observed warming. This is because, following current best estimates, negative aerosol forcing has substantially offset the GHG-induced warming. We also consider the expected warming from all anthropogenic forcings using the same probabilistic framework. This requires a re-assessment of the range of possible values for aerosol forcing. We provide evidence that the IPCC estimate for the upper bound of indirect aerosol forcing is almost certainly too high. Our results show that the expected warming due to all human influences since 1950 (including aerosol effects) is very similar to the observed warming. Including the effects of natural external forcing factors has a relatively small impact on our 1950–2005 results, but improves the correspondence between model and observations over 1900–2005. Over the longer period, however, externally forced changes are insufficient to explain the early twentieth century warming. We suggest that changes in the formation rate of North Atlantic Deep Water may have been a significant contributing factor.


Global warming Probabilistic calculations Climate Human influences Solar forcing NADW Aerosol forcing 

Supplementary material

382_2012_1585_MOESM1_ESM.doc (41 kb)
Supplementary material 1 (DOC 41 kb)


  1. Allen MR (2011) In defense of the traditional null hypothesis: remarks on the Trenberth and Curry WIREs opinion articles. WIREs Clim Change 2011(2):931–934. doi: 10.1002/wcc145 CrossRefGoogle Scholar
  2. Anderson TL, Charlson RJ, Schwartz SE, Knutti R, Boucher O, Rohde H, Heintzenberg J (2003) Climate forcing by aerosols—a hazy picture. Science 300:1103–1104CrossRefGoogle Scholar
  3. Andronova NG, Schlesinger ME (2001) Objective estimation of the probability density function for climate sensitivity. J Geophys Res 106:22605–22611CrossRefGoogle Scholar
  4. Bjerknes J (1964) Atlantic air–sea interaction. Adv Geophys 10:1–82CrossRefGoogle Scholar
  5. Brohan P, Kennedy J, Harris I, Tett SFB, Jones PD (2006) Uncertainty estimates in regional and global observed temperature changes: a new dataset from 1850. J Geophys Res 111:D12106. doi: 10.1029/2005JD006548 CrossRefGoogle Scholar
  6. Charlson RJ, Lovelock JE, Andreae MO, Warren SG (1987) Oceanic phytoplankton, atmospheric sulfur, cloud albedo and climate. Nature 326:655–661CrossRefGoogle Scholar
  7. Cunningham SA, Marsh R (2010) Observing and modeling changes in the Atlantic MOC. WIREs Clim Change 1:180–191. doi: 10.1002/wcc22 Google Scholar
  8. Cunningham SA, Kaznow T, Rayner D, Baringer MO, Johns WE, Marotzke J, Longworth HR, Grant EM, Hirschi JJ-M, Beal LM, Meinen CS, Bryden HL (2007) Temporal variability of the Atlantic meridional overturning circulation at 26.5°N. Science 317:935–938CrossRefGoogle Scholar
  9. Curry JA, Webster PJ (2011) Climate science and the uncertainty monster. Bull Am Meteorol Soc 92:1667–1682. doi: 10.1175/2011BAMS3139.1 CrossRefGoogle Scholar
  10. Delworth TL, Manabe S, Stouffer RJ (1993) Interdecadal variations of the thermohaline circulation in a coupled ocean–atmosphere model. J Clim 6:1993–2011CrossRefGoogle Scholar
  11. Forest CE, Stone PH, Sokolov AP (2006) Estimated PDFs of climate system properties including natural and anthropogenic forcings. Geophys Res Lett 33:L01705. doi: 10.1029/2005GL023977 CrossRefGoogle Scholar
  12. Foukal P (2002) A comparison of variable solar total and ultraviolet outputs in the 20th century. Geophys Res Lett 29:4377–4380. doi: 10.1029/2002GL015474 CrossRefGoogle Scholar
  13. Foukal P, North G, Wigley TML (2004) A stellar view on solar variations and climate. Science 306:68–69CrossRefGoogle Scholar
  14. Foukal P, Fröhlich C, Spruit H, Wigley TML (2006) Physical mechanisms of solar luminosity variation, and its effect on climate. Nature 443:161–166CrossRefGoogle Scholar
  15. Foukal P, Ortiz A, Schnerr R (2011) Dimming of the 17th century sun. Ap J Lett 733:L38. doi: 10.1088/2041-8205/733/2/L38 CrossRefGoogle Scholar
  16. Fröhlich C (2006) Solar irradiance variability since 1978. Space Sci Rev 125:53–65. doi: 10.1007/s11214-006-9046-5 CrossRefGoogle Scholar
  17. Gregory JM, Dixon KW, Stouffer RJ, Weaver AJ, Driesschaert E, Eby M, Fichefet T, Hasumi H, Hu A, Jungclaus JH, Kamenkovich IV, Levermann A, Montoya M, Murakami S, Nawrath S, Oka A, Sokolov AP, Thorpe RB (2005) A model intercomparison of changes in the Atlantic thermohaline circulation in response to increasing atmospheric CO2 concentration. Geophys Res Lett 32:L12703. doi: 10.1029/2005GL023209 CrossRefGoogle Scholar
  18. Hansen J, Ruedy R, Glascoe J, Sato M (1999) GISS analysis of surface temperature change. J Geophys Res 104:30997–31022. doi: 10.1029/1999JD900835 CrossRefGoogle Scholar
  19. Hansen JE, Ruedy R, Sato M, Imhoff M, Lawrence W, Easterling D, Peterson T, Karl T (2001) A closer look at United States and global surface temperature change. J Geophys Res 106:23947–23963. doi: 10.1029/2001JD000354 CrossRefGoogle Scholar
  20. Hansen J, Ruedy R, Glascoe J, Sato M (2006) GISS analysis of surface temperature change. Proc Natl Acad Sci 103:14288–14293CrossRefGoogle Scholar
  21. IPCC (Intergovernmental Panel on Climate Change) (2001) Climate change 2001: the physical science basis, contribution of working group I to the third assessment report of the intergovernmental panel on climate change. In: Houghton JT, Ding Y, Griggs DJ, Noguer M, Meehl G, van der Linden PJ, Dai X, Maskell K, Johnson CA (eds) Cambridge University Press, Cambridge, UKGoogle Scholar
  22. IPCC (Intergovernmental Panel on Climate Change) (2007) Summary for policymakers. In: Solomon S, Qin D, Manning M, Chen Z, Marquis M, Averyt KB, Tignor M, Miller HL (eds) Climate change 2007: the physical science basis, contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change. Cambridge University Press, Cambridge, UK, pp 1–18Google Scholar
  23. Jones PD, Wigley TML (2010) Estimation of global temperature trends: what’s important and what isn’t. Clim Change 100:59–69. doi: 10.1007/s10584-010-9836-3 CrossRefGoogle Scholar
  24. Katsman CA, van Oldenborgh GJ (2011) Tracing the ocean’s “missing heat”. Geophys Res Lett 38:L14610. doi: 10.1029/2011GL048417 Google Scholar
  25. Knight JR, Allan RJ, Folland CK, Vellinga M, Mann ME (2005) A signature of persistent natural thermohaline circulation cycles in observed climate. Geophys Res Lett 32:L20708. doi: 10.1029/2005GL024233 CrossRefGoogle Scholar
  26. Knutti R, Stocker TF, Joos F, Plattner G-K (2002) Constraints on radiative forcing and future climate change from observations and climate model ensembles. Nature 416:719–723CrossRefGoogle Scholar
  27. Knutti R, Stocker TF, Joos F, Plattner G-K (2003) Probabilistic climate change projections using neural networks. Clim Dyn 21:257–272CrossRefGoogle Scholar
  28. Lean J (2000) Evolution of the Sun’s spectral irradiance since the Maunder Minumum. Geophys Res Lett 27:2425–2428CrossRefGoogle Scholar
  29. Medhaug I, Langehaug HR, Eldevik T, Furevik T, Bentsen M (2012) Mechanisms for decadal scale variability in a simulated Atlantic meridional overturning circulation. Clim Dyn 39:77–93. doi: 10:1007/s00382-011-1124-z CrossRefGoogle Scholar
  30. Meehl GA, Stocker TF, Collins WD, Friedlingstein P, Gaye AT, Gregory JM, Kitoh A, Knutti R, Murphy JM, Noda A, Raper SCB, Watterson IG, Weaver AJ, Zhao Z-C (2007) Global climate projections. In: Solomon S, Qin D, Manning M, Chen Z, Marquis M, Averyt KB, Tignor M, Miller HL (eds) Climate change 2007: the physical science basis, contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change. Cambridge University Press, Cambridge, UK, pp 747–845Google Scholar
  31. Meinshausen M, Meinshausen N, Hare W, Raper SCB, Frieler K, Knutti R, Frame DJ, Allen MR (2009–supplementary information) Greenhouse-gas emission targets for limiting global warming to 2°C. Nature 458:1158–1162Google Scholar
  32. Meinshausen M, Raper SCB, Wigley TML (2011) Emulating coupled atmosphere–ocean and carbon cycle models with a simpler model, MAGICC6—part I: model description and calibration. Atmos Chem Phys 11:1417–1456CrossRefGoogle Scholar
  33. Menary MB, Park W, Lohmann K, Vellinga M, Palmer MD, Latif M, Jungclaus JH (2012) A multimodel comparison of centennial Atlantic meridional overturning circulation variability. Clim Dyn 38:2377–2388. doi: 10.1007/s00382-011-1172-4 CrossRefGoogle Scholar
  34. Michaels PJ (1992) Global warming: beyond the popular vision. In: Majumdar SK, Kalkstein LS, Yarnal B, Miller EW, Rosenfeld LM (eds) Global climate change: implications, challenges and mitigation measures. The Pennsylvania Academy of Science, Pennsylvania, pp 100–116Google Scholar
  35. Mitchell JM Jr (1971) The effect of atmospheric aerosols on climate with special reference to temperature near the Earth’s surface. J Appl Meteorol 10:703–714CrossRefGoogle Scholar
  36. Morice CP, Kennedy JJ, Rayner NA, Jones PD (2012) Quantifying uncertainties in global and regional temperature change using an ensemble of observational estimates: the HadCRUT4 data set. J Geophys Res 117:D08101. doi: 10.1029/2011JD017187 CrossRefGoogle Scholar
  37. Parker DE, Folland CK, Scaife AA, Knight JR, Colman A, Baines P, Dong B (2007) Decadal to multidecadal variability and the climate change background. J Geophys Res 112:D18115. doi: 10.1029/2007JD008411.` CrossRefGoogle Scholar
  38. Raper SCB, Gregory JM, Osborn TJ (2001) Use of an upwelling-diffusion energy balance climate model to simulate and diagnose A/OGCM results. Clim Dyn 17:601–613CrossRefGoogle Scholar
  39. Santer BD, Taylor KE, Wigley TML, Penner JE, Jones PD, Cubasch U (1995) Towards the detection and attribution of an anthropogenic effect on climate. Clim Dyn 12:77–100CrossRefGoogle Scholar
  40. Santer BD, Wigley TML, Doutriaux C, Boyle JS, Hansen JE, Jones PD, Meehl GA, Roeckner E, Sengupta S, Taylor KE (2001) Accounting for the effects of volcanoes and ENSO in comparisons of modeled and observed temperature trends. J Geophys Res 106:28033–28059CrossRefGoogle Scholar
  41. Santer BD, Mears C, Doutriaux C, Caldwell P, Gleckler PJ, Wigley TML, Solomon S, Gillett NP, Ivanova D, Karl TR, Lanzante JR, Meehl GA, Stott PA, Taylor KE, Thorne PW, Wehner MF, Wentz FJ (2011) Separating signal and noise in atmospheric temperature changes: the importance of timescale. J Geophys Res 116:D22105. doi: 10.1029/2011JD016263 CrossRefGoogle Scholar
  42. Sato M, Hansen JE, McCormick MP, Pollack JB (1993) Stratospheric aerosol optical depth, 1850–1990. J Geophys Res 98:22987–22994CrossRefGoogle Scholar
  43. Schaeffer M, Selten FM, Opsteegh JD, Goosse H (2004) The influence of ocean convection patterns on high-latitude climate projections. J Clim 17:4316–4329CrossRefGoogle Scholar
  44. Schlesinger ME, Ramankutty N (1994) An oscillation in the global climate system of period 65–70 years. Nature 367:723–726CrossRefGoogle Scholar
  45. Schlesinger ME, Ramankutty N (1995) Is the recently reported 65- to 70-year surface-temperature oscillation the result of climatic noise? J Geophys Res 100:13,767–13,774Google Scholar
  46. Schlesinger ME, Yin J, Yohe G, Andronova NG, Malyshev S, Li B (2006) Assessing the risk of a collapse of the Atlantic thermohaline circulation. In: Schellnhuber HJ, Cramer W, Nakićenović N, Wigley TML, Yohe G (eds) Avoiding dangerous climate change. Cambridge University Press, Cambridge, pp 37–47Google Scholar
  47. Smith TM, Reynolds RW (2005) A global merged land and sea surface temperature reconstruction based on historical observations (1880–1997). J Clim 18:2021–2036CrossRefGoogle Scholar
  48. Smith SJ, Pitcher H, Wigley TML (2001) Global and regional anthropogenic sulfur dioxide emissions. Glob Planet Change 29:99–119CrossRefGoogle Scholar
  49. Smith TM, Reynolds RW, Peterson TC, Lawrimore J (2008) Improvements to NOAA’s historical merged land-ocean surface temperature analysis (1880–2006). J Clim 21:2283–2293CrossRefGoogle Scholar
  50. Smith SJ, van Aardenne J, Klimont Z, Andres RJ, Volke A, Delgado Arias S (2011) Anthropogenic sulfur dioxide emissions: 1850–2005. Atmos Chem Phys 11:1101–1116. doi: 10.5194/acp-11-1101-2011 CrossRefGoogle Scholar
  51. Stott PA, Mitchell JFB, Allen MR, Delworth TL, Gregory JM, Meehl GA, Santer BD (2006) Observational constraints on past attributable warming and predictions of future global warming. J Clim 19:3055–3069CrossRefGoogle Scholar
  52. Stouffer RJ, Yin J, Gregory JM, Dixon KW, Spelman MJ, Hurlin W, Weaver AJ, Eby M, Flato GM, Hasumi H, Hu A, Jungclaus JH, Kamenkovich IV, Levermann A, Montoya M, Murakami S, Nawrath S, Oka A, Peltier WD, Robitaille DY, Sokolov A, Vettoretti G, Weber SL (2006) Investigating the causes of the response of the thermohaline circulation to past and future climate changes. J Clim 19:1365–1387Google Scholar
  53. Swanson KL, Sugihara G, Tsonis AA (2009) Long-term natural variability and 20th century climate change. Proc Natl Acad Sci 106:16120–16123. doi: 10.1073/pnas.0908699106 CrossRefGoogle Scholar
  54. Trenberth KE, Shea DJ (2006) Atlantic hurricanes and natural variability in 2005. Geophys Res Lett 33:L12704. doi: 10.1029/2006GL026894 CrossRefGoogle Scholar
  55. Vernier J-P, Thomason LW, Pommereau J-P, Bourassa A, Pelon J, Garnier A, Hauchecorne A, Blanot L, Trepte C, Degenstein D, Vargas F (2011) Major influence of tropical volcanic eruptions on the stratospheric aerosol layer during the last decade. Geophys Res Lett 38:L12807. doi: 10.1029/2011GL047563 Google Scholar
  56. Wang Y-M, Lean J, Sheeley NR Jr (2005) Modeling the Sun’s magnetic field and irradiance since 1713. Astrophys J 625:522–538CrossRefGoogle Scholar
  57. Wigley TML (1989) Possible climatic change due to SO2-derived cloud condensation nuclei. Nature 339:365–367CrossRefGoogle Scholar
  58. Wigley TML (2000) ENSO, volcanoes and record breaking temperatures. Geophys Res Lett 27:4101–4104CrossRefGoogle Scholar
  59. Wigley TML, Raper SCB (1987) Thermal expansion of sea water associated with global warming. Nature 330:127–131CrossRefGoogle Scholar
  60. Wigley TML, Raper SCB (2001) Interpretation of high projections for global-mean warming. Science 293:451–454CrossRefGoogle Scholar
  61. Wigley TML, Clarke LE, Edmonds JA, Jacoby HD, Paltsev S, Pitcher H, Reilly JM, Richels R, Sarofim MC, Smith SJ (2009) Uncertainties in climate stabilization. Clim Change 97:85–121. doi: 10.1007/s10584-009-9585-3 CrossRefGoogle Scholar
  62. Wu Z, Huang NE, Long SR, Peng C-K (2007) On the trend, detrending and variability of nonlinear and non-stationary time series. Proc Natl Acad Sci 104:14889–14894CrossRefGoogle Scholar
  63. Wu Z, Huang NE, Wallace JM, Smoliak BV, Chen X (2011) On the time-varying trend in global-mean surface temperature. Clim Dyn 37:759–773. doi: 10.1007/s00382-011-1128-8 CrossRefGoogle Scholar
  64. Yin J, Schlesinger ME, Andronova NG, Malyshev S, Li B (2006) Is a shutdown of the thermohaline circulation irreversible? J Geophys Res 111:D12104. doi: 10.1029/2005JD006562 CrossRefGoogle Scholar
  65. Zhang R, Delworth TL, Held IM (2007) Can the Atlantic Ocean drive the observed multidecadal variability in Northern Hemisphere mean temperature? Geophys Res Lett 34:L02709. doi: 10.1029/2006GL028683 CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.National Center for Atmospheric ResearchBoulderUSA
  2. 2.University of AdelaideAdelaideAustralia
  3. 3.Program for Climate Model Diagnosis and IntercomparisonLawrence Livermore National LaboratoryLivermoreUSA

Personalised recommendations