• Allan, R. P., C. Liu, M. Zahn, D. A. Lavers, E. Koukouvagias, and A. Bodas-Salcedo, 2013: Physically consistent responses of the global atmospheric hydrological cycle in models and observations. Surv. Geophys., doi:10.1007/s10712-012-9213-z.

    • Search Google Scholar
    • Export Citation
  • Anderson, B. T., J. R. Knight, M. A. Ringer, C. Deser, A. S. Phillips, J.-H. Yoon, and A. Cherchi, 2010: Climate forcings and climate sensitivities diagnosed from atmospheric global circulation models. Climate Dyn., 35, 14611475, doi:10.1007/s00382-010-0798-y.

    • Search Google Scholar
    • Export Citation
  • Anderson, B. T., J. R. Knight, M. A. Ringer, J. Yoon, and A. Cherchi, 2012: Testing for the possible influence of unknown climate forcings upon global temperature increases from 1950 to 2000. J. Climate, 25, 71637172.

    • Search Google Scholar
    • Export Citation
  • Andrews, T., 2009: Forcing and response in simulated 20th and 21st century surface energy and precipitation trends. J. Geophys. Res., 114, D17110, doi:10.1029/2009JD011749.

    • Search Google Scholar
    • Export Citation
  • Andrews, T., P. M. Forster, O. Boucher, N. Bellouin, and A. Jones, 2010: Precipitation, radiative forcing and global temperature change. Geophys. Res. Lett., 27, L14701, doi:10.1029/2010GL043991.

    • Search Google Scholar
    • Export Citation
  • Andrews, T., J. M. Gregory, P. M. Forster, and M. J. Webb, 2012a: Cloud adjustment and its role in CO2 radiative forcing and climate sensitivity: A review. Surv. Geophys., 33, 619635, doi:10.1007/s10712-011-9152-0.

    • Search Google Scholar
    • Export Citation
  • Andrews, T., J. M. Gregory, M. J. Webb, and K. E. Taylor, 2012b: Forcing, feedbacks and climate sensitivity in CMIP5 coupled atmosphere-ocean climate models. Geophys. Res. Lett., 39, L09712, doi:10.1029/2012GL051607.

    • Search Google Scholar
    • Export Citation
  • Armour, K. C., C. M. Bitz, and G. H. Roe, 2013: Time-varying climate sensitivity from regional feedbacks. J. Climate, 26, 45184534.

  • Bellouin, N., J. Rae, A. Jones, C. Johnson, J. Haywood, and O. Boucher, 2011: Aerosol forcing in the Climate Model Intercomparison Project (CMIP5) simulations by HadGEM2-ES and the role of ammonium nitrate. J. Geophys. Res., 116, D20206, doi:10.1029/2011JD016074.

    • Search Google Scholar
    • Export Citation
  • Bichet, A., M. Wild, D. Folini, and C. Schär, 2011: Global precipitation response to changing forcings since 1870. Atmos. Chem. Phys., 11, 99619970.

    • Search Google Scholar
    • Export Citation
  • Bichet, A., M. Wild, D. Folini, and C. Schär, 2012: Causes for decadal variations of wind speed over land: Sensitivity studies with a global climate model. Geophys. Res. Lett., 39, L11701, doi:10.1029/2012GL051685.

    • Search Google Scholar
    • Export Citation
  • Bony, S., M. Webb, C. Bretherton, S. Klein, P. Siebesma, G. Tselioudis, and M. Zhang, 2011: CFMIP: Towards a better evaluation and understanding of clouds and cloud feedbacks in CMIP5 models. CLIVAR Exchanges, No. 56, International CLIVAR Project Office, Southampton, United Kingdom, 20–24.

  • Bony, S., G. Bellon, D. Klocke, S. Sherwood, S. Fermepin, and S. Denvil, 2013: Robust direct effect of carbon dioxide on tropical circulation and regional precipitation. Nat. Geosci., 6, 447–451, doi:10.1038/ngeo1799.

    • Search Google Scholar
    • Export Citation
  • Bosilovich, M. G., S. D. Schubert, and G. K. Walker, 2005: Global changes of the water cycle intensity. J. Climate,18, 1591–1608.

  • Butchart, N., and Coauthors, 2006: Simulations of anthropogenic change in the strength of the Brewer–Dobson circulation. Climate Dyn., 27, 727741, doi:10.1007/s00382-006-0162-4.

    • Search Google Scholar
    • Export Citation
  • Caminade, C., and L. Terray, 2006: Influence of increased greenhouse gases and sulphate aerosols concentration upon diurnal temperature range over Africa at the end of the 20th century. Geophys. Res. Lett., 33, L15703, doi:10.1029/2006GL026381.

    • Search Google Scholar
    • Export Citation
  • Cao, L., G. Bala, and K. Caldeira, 2012: Climate response to changes in atmospheric carbon dioxide and solar irradiance on the time scale of days to weeks. Environ. Res. Lett., 7, 034015, doi:10.1088/1748-9326/7/3/034015.

    • Search Google Scholar
    • Export Citation
  • Deser, C., and A. S. Phillips, 2009: Atmospheric circulation trends, 1950–2000: The relative roles of sea surface temperature forcing and direct atmospheric radiative forcing. J. Climate, 22, 396413.

    • Search Google Scholar
    • Export Citation
  • Dessler, A. E., 2010: A determination of the cloud feedback from climate variations over the past decade. Science, 330, 15231527, doi:10.1126/science.1192546.

    • Search Google Scholar
    • Export Citation
  • Dong, B., J. M. Gregory, and R. T. Sutton, 2009: Understanding land–sea warming contrast in response to increasing greenhouse gases. Part I: Transient adjustment. J. Climate, 22, 30793097.

    • Search Google Scholar
    • Export Citation
  • Folland, C. K., D. M. H. Sexton, D. J. Karoly, C. E. Johnson, D. P. Rowell, and D. E. Parker, 1998: Influences of anthropogenic and oceanic forcing on recent climate change. Geophys. Res. Lett., 25 ,353356.

    • Search Google Scholar
    • Export Citation
  • Folland, C. K., J. Shukla, J. Kinter, and M. J. Rodwell, 2002: The climate of the twentieth century project. CLIVAR Exchanges, No. 7, International CLIVAR Project Office, Southampton, United Kingdom, 37–39.

  • Forster, P. M., and J. M. Gregory, 2006: The climate sensitivity and its components diagnosed from Earth Radiation Budget data. J. Climate, 19, 3952.

    • Search Google Scholar
    • Export Citation
  • Forster, P. M., and K. Taylor, 2006: Climate forcings and climate sensitivities diagnosed from coupled climate model integrations. J. Climate, 19, 61816194.

    • Search Google Scholar
    • Export Citation
  • Forster, P. M., R. S. Freckleton, and K. P. Shine, 1997: On aspects of the concept of radiative forcing. Climate Dyn., 13, 547560.

  • Forster, P. M., and Coauthors, 2011: Evaluation of radiation scheme performance within chemistry climate models. J. Geophys. Res., 116, D10302, doi:10.1029/2010JD015361.

    • Search Google Scholar
    • Export Citation
  • Forster, P. M., T. Andrews, P. Good, J. M. Gregory, L. S. Jackson, and M. Zelinka, 2013: Evaluating adjusted forcing and model spread for historical and future scenarios in the CMIP5 generation of climate models. J. Geophys. Res., 118, 1139–1150, doi:10.1002/jgrd.50174.

    • Search Google Scholar
    • Export Citation
  • Frieler, K., M. Meinshausen, T. Schneider von Deimling, T. Andrews, and P. Forster, 2011: Changes in global-mean precipitation in response to warming, greenhouse gas forcing and black carbon. Geophys. Res. Lett., 38, L04702, doi:10.1029/2010GL045953.

    • Search Google Scholar
    • Export Citation
  • Gates, W. L., 1992: AMIP: The Atmospheric Model Intercomparison Project. Bull. Amer. Meteor. Soc., 73, 19621970.

  • Gates, W. L., and Coauthors, 1999: An overview of the results of the Atmospheric Model Intercomparison Project (AMIP I). Bull. Amer. Meteor. Soc., 80, 2955.

    • Search Google Scholar
    • Export Citation
  • Gettelman, A., and Coauthors, 2010: Multimodel assessment of the upper troposphere and lower stratosphere: Tropics and global trends. J. Geophys. Res.,115 , D00M08, doi:10.1029/2009JD013638.

    • Search Google Scholar
    • Export Citation
  • Gregory, J. M., and P. Forster, 2008: Transient climate response estimated from radiative forcing and observed temperature change. J. Geophys. Res., 113, D23105, doi:10.1029/2008JD010405.

    • Search Google Scholar
    • Export Citation
  • Gregory, J. M., and M. J. Webb, 2008: Tropospheric adjustment induces a cloud component in CO2 forcing. J. Climate, 21, 5871.

  • Gregory, J. M., and Coauthors, 2004: A new method for diagnosing radiative forcing and climate sensitivity. Geophys. Res. Lett., 31, L03205, doi:10.1029/2003GL018747.

    • Search Google Scholar
    • Export Citation
  • Hansen, J., M. Sato, and R. Ruedy, 1997: Radiative forcing and climate response. J. Geophys. Res., 102 (D6), 68316864.

  • Hansen, J., and Coauthors, 2002: Climate forcings in Goddard Institute for Space Studies SI2000 simulations. J. Geophys. Res., 107, 4347, doi:10.1029/2001JD001143.

    • Search Google Scholar
    • Export Citation
  • Hansen, J., and Coauthors, 2005: Efficacy of climate forcings. J. Geophys. Res., 110, D18104, doi:10.1029/2005JD005776.

  • Held, I. M., and B. J. Soden, 2006: Robust responses of the hydrological cycle to global warming. J. Climate, 19, 56865699.

  • Held, I. M., M. Winton, K. Takahasi, T. Delworth, F. Zeng, and G. K. Vallis, 2010: Probing the fast and slow components of global warming by returning abruptly to preindustrial forcing. J. Climate, 23, 24182427.

    • Search Google Scholar
    • Export Citation
  • Jiang, J. H., and Coauthors, 2012: Evaluation of cloud and water vapor simulations in CMIP5 climate models using NASA “A-Train” satellite observations. J. Geophys. Res., 117, D14105, doi:10.1029/2011JD017237.

    • Search Google Scholar
    • Export Citation
  • Jones, C. D., and Coauthors, 2011: The HadGEM2-ES implementation of the CMIP5 centennial simulations. Geosci. Model Dev., 4, 543570, doi:10.5194/gmd-4-543-2011.

    • Search Google Scholar
    • Export Citation
  • Keeling, C. D., R. B. Bacastow, A. E. Bainbridge, C. A. Ekdahl, P. R. Guenther, L. S. Waterman, and J. F. S. Chin, 1976: Atmospheric carbon dioxide variations at Mauna Loa Observatory, Hawaii. Tellus, 28, 538551.

    • Search Google Scholar
    • Export Citation
  • Kiehl, J. T., 2007: Twentieth century climate model response and climate sensitivity. Geophys. Res. Lett., 34, L22710, doi:10.1029/2007GL031383.

    • Search Google Scholar
    • Export Citation
  • King, M. P., F. Kucharski, and F. Molteni, 2010: The roles of external forcings and internal variabilities in the Northern Hemisphere atmospheric circulation change from the 1960s to the 1990s. J. Climate, 23, 62006220.

    • Search Google Scholar
    • Export Citation
  • Knutti, R., and J. Sedlacek, 2013: Robustness and uncertainties in the new CMIP5 climate model projections. Nat. Climate Change, 3, 369373, doi:10.1038/nclimate1716.

    • Search Google Scholar
    • Export Citation
  • Kucharski, F., and Coauthors, 2009: The CLIVAR C20C project: Skill of simulating Indian monsoon rainfall on interannual to decadal timescales. Does GHG forcing play a role? Climate Dyn., 33, 615627, doi:10.1007/s00382-008-0462-y.

    • Search Google Scholar
    • Export Citation
  • Lambert, F. H., and M. J. Webb, 2008: Dependence of global mean precipitation on surface temperature. Geophys. Res. Lett., 35, L16706, doi:10.1029/2008GL034838.

    • Search Google Scholar
    • Export Citation
  • Loeb, N. G., B. A. Wielicki, D. R. Doelling, G. Louis Smith, D. F. Keyes, S. Kato, N. Manalo-Smith, and T. Wong, 2009: Toward optimal closure of the earth’s top-of-atmosphere radiation budget. J. Climate, 22, 748766.

    • Search Google Scholar
    • Export Citation
  • Lohmann, U., and Coauthors, 2010: Total aerosol effect: Radiative forcing or radiative flux perturbation? Atmos. Chem. Phys., 10, 32353246.

    • Search Google Scholar
    • Export Citation
  • Manabe, S., and R. T. Wetherald, 1975: The effects of doubling the CO2 concentration on the climate of a general circulation model. J. Atmos. Sci., 32, 315.

    • Search Google Scholar
    • Export Citation
  • Martin, G. M., and Coauthors, 2011: The HadGEM2 family of Met Office Unified Model Climate configurations. Geosci. Model Dev., 4, 723757, doi:10.5194/gmd-4-723-2011.

    • Search Google Scholar
    • Export Citation
  • McLandress, C., and T. G. Shepherd, 2009: Simulated anthropogenic changes in the Brewer–Dobson circulation, including its extension to high latitudes. J. Climate, 22, 15161540.

    • Search Google Scholar
    • Export Citation
  • Meehl, G. A., A. Hu, J. M. Arblaster, J. Fasullo, and K. E. Trenberth, 2013: Externally forced and internally generated decadal climate variability associated with the interdecadal Pacific oscillation. J. Climate, 26, 72987310.

    • Search Google Scholar
    • Export Citation
  • Ming, Y., and V. Ramaswamy, 2012: Nonlocal component of radiative flux perturbation. Geophys. Res. Lett., 39, L22706, doi:10.1029/2012GL054050.

    • Search Google Scholar
    • Export Citation
  • Ming, Y., V. Ramaswamy, and G. Persad, 2010: Two opposing effects of absorbing aerosols on global-mean precipitation. Geophys. Res. Lett., 37, L13701, doi:10.1029/2010GL042895.

    • Search Google Scholar
    • Export Citation
  • Mitchell, J. F. B., C. A. Wilson, and W. M. Cunnington, 1987: On CO2 climate sensitivity and model dependence of results. Quart. J. Roy. Meteor. Soc., 113, 293322.

    • Search Google Scholar
    • Export Citation
  • 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 data set. J. Geophys. Res., 117, D08101, doi:10.1029/2011JD017187.

    • Search Google Scholar
    • Export Citation
  • Muller, C. J., and P. A. O’Gorman, 2011: An energetic perspective on the regional response of precipitation to climate change. Nat. Climate Change, 1, 266271.

    • Search Google Scholar
    • Export Citation
  • Murphy, D. M., 2013: Little net clear-sky radiative forcing from recent regional redistribution of aerosols. Nat. Geosci., 6, 258262, doi:10.1038/NGEO1740.

    • Search Google Scholar
    • Export Citation
  • Murphy, D. M., S. Solomon, R. W. Portmann, K. H. Rosenlof, P. M. Forster, and T. Wong, 2009: An observationally based energy balance for the Earth since 1950. J. Geophys. Res., 114, D17107, doi:10.1029/2009JD012105.

    • Search Google Scholar
    • Export Citation
  • Myhre, G., E. J. Highwood, K. P. Shine, and F. Stordal, 1998: New estimates of radiative forcing due to well mixed greenhouse gases. Geophys. Res. Lett., 25,27152718.

    • Search Google Scholar
    • Export Citation
  • Patricola, C. M., and K. H. Cook, 2011: Sub-Saharan northern African climate at the end of the twenty-first century: Forcing factors and climate change processes. Climate Dyn., 37, 11651188, doi:10.1007/s00382-010-0907-y.

    • Search Google Scholar
    • Export Citation
  • Rotstayn, L. D., and J. E. Penner, 2001: Indirect aerosol forcing, quasi forcing, and climate response. J. Climate, 14, 29602975.

  • Scaife, A., and Coauthors, 2009: The CLIVAR C20C project: Selected twentieth century climate events. Climate Dyn., 33, 603614, doi:10.1007/s00382-008-0451-1.

    • Search Google Scholar
    • Export Citation
  • Seidel, D. J., N. P. Gillett, J. R. Lanzante, K. P. Shine, and P. W. Thorne, 2011: Stratospheric temperature trends: Our evolving understanding. Wiley Interdiscip. Rev. Climate Change, 2, 592616, doi:10.1002/wcc.125.

    • Search Google Scholar
    • Export Citation
  • Senior, C. A., and J. F. B. Mitchell, 2000: The time-dependence of climate sensitivity. Geophys. Res. Lett., 17 ,26852688.

  • Sexton, D. M. H., D. P. Rowell, C. K. Folland, and D. J. Karoly, 2001: Detection of anthropogenic climate change using an atmospheric GCM. Climate Dyn., 17, 669685.

    • Search Google Scholar
    • Export Citation
  • Shindell, D. T., and Coauthors, 2013: Radiative forcing in the ACCMIP historical and future climate simulations. Atmos. Chem. Phys., 13, 29392974, doi:10.5194/acp-13-2939-2013.

    • Search Google Scholar
    • Export Citation
  • Shine, K. P., and P. M. Forster, 1999: The effect of human activity on radiative forcing of climate: A review of recent development. Global Planet. Change, 20, 202225.

    • Search Google Scholar
    • Export Citation
  • Shine, K. P., J. Cook, E. J. Highwood, and M. J. Joshi, 2003a: An alternative to radiative forcing for estimating the relative importance of climate change mechanisms. Geophys. Res. Lett., 30, 2047, doi:10.1029/2003GL018141.

    • Search Google Scholar
    • Export Citation
  • Shine, K. P., and Coauthors, 2003b: A comparison of model-simulated trends in stratospheric temperatures. Quart. J. Roy. Meteor. Soc., 129, 15651588, doi:10.1256/qj.02.186.

    • Search Google Scholar
    • Export Citation
  • Skinner, C. B., M. Ashfaq, and N. S. Diffenbaugh, 2012: Influence of twenty-first-century atmospheric and sea surface temperature forcing on West African climate. J. Climate, 25, 527542.

    • Search Google Scholar
    • Export Citation
  • Soden, B. J., A. J. Broccoli, and R. S. Hemler, 2004: On the use of cloud forcing to estimate cloud feedback. J. Climate, 17, 36613665.

    • Search Google Scholar
    • Export Citation
  • Soden, B. J., I. M. Held, R. Colman, K. M. Shell, J. T. Kiehl, and C. A. Shields, 2008: Quantifying climate feedbacks using radiative kernels. J. Climate, 21, 35043520.

    • Search Google Scholar
    • Export Citation
  • Stephens, G. L., and Coauthors, 2012: An update on Earth’s energy balance in light of the latest global observations. Nat. Geosci., 5, 691696, doi:10.1038/ngeo1580.

    • Search Google Scholar
    • Export Citation
  • Streets, D. G., and Coauthors, 2009: Anthropogenic and natural contributions to regional trends in aerosol optical depth, 1980–2006. J. Geophys. Res., 114, D00D18, doi:10.1029/2008JD011624.

    • Search Google Scholar
    • Export Citation
  • Taylor, K. E., R. J. Stouffer, and G. A. Meehl, 2012: An overview of CMIP5 and the experiment design. Bull. Amer. Meteor. Soc., 93, 485–498.

    • Search Google Scholar
    • Export Citation
  • Thompson, D. W. J, and Coauthors, 2012: The mystery of recent stratospheric temperature trends. Nature,491, 692–697.

  • Thorne, P. W., J. R. Lanzante, T. C. Peterson, D. J. Seidel, and K. P. Shine, 2011: Tropospheric temperature trends: History of an ongoing controversy. Wiley Interdiscip. Rev. Climate Change, 2, 6688, doi:10.1002/wcc.80.

    • Search Google Scholar
    • Export Citation
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Using an AGCM to Diagnose Historical Effective Radiative Forcing and Mechanisms of Recent Decadal Climate Change

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  • 1 Met Office Hadley Centre, Exeter, United Kingdom
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Abstract

An atmospheric general circulation model is forced with observed monthly sea surface temperature and sea ice boundary conditions, as well as forcing agents that vary in time, for the period 1979–2008. The simulations are then repeated with various forcing agents, individually and in combination, fixed at preindustrial levels. The simple experimental design allows the diagnosis of the model’s global and regional time-varying effective radiative forcing from 1979 to 2008 relative to preindustrial levels. Furthermore the design can be used to (i) calculate the atmospheric model’s feedback/sensitivity parameters to observed changes in sea surface temperature and (ii) separate those aspects of climate change that are directly driven by the forcing from those driven by large-scale changes in sea surface temperature. It is shown that the atmospheric response to increased radiative forcing over the last 3 decades has halved the global precipitation response to surface warming. Trends in sea surface temperature and sea ice are found to contribute only ~60% of the global land, Northern Hemisphere, and summer land warming trends. Global effective radiative forcing is ~1.5 W m−2 in this model, with anthropogenic and natural contributions of ~1.3 and ~0.2 W m−2, respectively. Forcing increases by ~0.5 W m−2 decade−1 over the period 1979–2008 or ~0.4 W m−2 decade−1 if years strongly influenced by volcanic forcings—which are nonlinear with time—are excluded from the trend analysis. Aerosol forcing shows little global decadal trend due to offsetting regional trends whereby negative aerosol forcing weakens in Europe and North America but continues to strengthen in Southeast Asia.

Corresponding author address: Timothy Andrews, Met Office Hadley Centre, FitzRoy Road, Exeter EX1 3PB, United Kingdom. E-mail: timothy.andrews@metoffice.gov.uk

Abstract

An atmospheric general circulation model is forced with observed monthly sea surface temperature and sea ice boundary conditions, as well as forcing agents that vary in time, for the period 1979–2008. The simulations are then repeated with various forcing agents, individually and in combination, fixed at preindustrial levels. The simple experimental design allows the diagnosis of the model’s global and regional time-varying effective radiative forcing from 1979 to 2008 relative to preindustrial levels. Furthermore the design can be used to (i) calculate the atmospheric model’s feedback/sensitivity parameters to observed changes in sea surface temperature and (ii) separate those aspects of climate change that are directly driven by the forcing from those driven by large-scale changes in sea surface temperature. It is shown that the atmospheric response to increased radiative forcing over the last 3 decades has halved the global precipitation response to surface warming. Trends in sea surface temperature and sea ice are found to contribute only ~60% of the global land, Northern Hemisphere, and summer land warming trends. Global effective radiative forcing is ~1.5 W m−2 in this model, with anthropogenic and natural contributions of ~1.3 and ~0.2 W m−2, respectively. Forcing increases by ~0.5 W m−2 decade−1 over the period 1979–2008 or ~0.4 W m−2 decade−1 if years strongly influenced by volcanic forcings—which are nonlinear with time—are excluded from the trend analysis. Aerosol forcing shows little global decadal trend due to offsetting regional trends whereby negative aerosol forcing weakens in Europe and North America but continues to strengthen in Southeast Asia.

Corresponding author address: Timothy Andrews, Met Office Hadley Centre, FitzRoy Road, Exeter EX1 3PB, United Kingdom. E-mail: timothy.andrews@metoffice.gov.uk
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