Mechanisms for the land/sea warming contrast exhibited by simulations of climate change

Abstract

The land/sea warming contrast is a phenomenon of both equilibrium and transient simulations of climate change: large areas of the land surface at most latitudes undergo temperature changes whose amplitude is more than those of the surrounding oceans. Using idealised GCM experiments with perturbed SSTs, we show that the land/sea contrast in equilibrium simulations is associated with local feedbacks and the hydrological cycle over land, rather than with externally imposed radiative forcing. This mechanism also explains a large component of the land/sea contrast in transient simulations as well. We propose a conceptual model with three elements: (1) there is a spatially variable level in the lower troposphere at which temperature change is the same over land and sea; (2) the dependence of lapse rate on moisture and temperature causes different changes in lapse rate upon warming over land and sea, and hence a surface land/sea temperature contrast; (3) moisture convergence over land predominantly takes place at levels significantly colder than the surface; wherever moisture supply over land is limited, the increase of evaporation over land upon warming is limited, reducing the relative humidity in the boundary layer over land, and hence also enhancing the land/sea contrast. The non-linearity of the Clausius–Clapeyron relationship of saturation specific humidity to temperature is critical in (2) and (3). We examine the sensitivity of the land/sea contrast to model representations of different physical processes using a large ensemble of climate model integrations with perturbed parameters, and find that it is most sensitive to representation of large-scale cloud and stomatal closure. We discuss our results in the context of high-resolution and Earth-system modelling of climate change.

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References

  1. Boer GJ, Yu B (2003) Climate sensitivity and response. Clim Dynam 20:415–429

    Google Scholar 

  2. Cess RD et al (1990) Intercomparison and interpretation of climate feedback processes in 19 atmospheric general circulation models. J Geophys Res 95:16601–16615

    Article  Google Scholar 

  3. Cubasch U, Meehl GA, Boer GJ, Stouffer RJ, Dix M, Noda A, Senior CA, Raper SCB, Yap KS (2001) Projections of future climate change, in Climate Change 2001, the scientific basis. Contribution of working group 1 to the 3rd assessment report of the IPCC. Cambridge University Press, Cambridge, pp 525–582. ensembles of general circulation model simulations. Clim Dynam 27:357–375

  4. Held IM, BJ Soden (2006) Robust responses of the hydrological cycle to global warming. J Clim 16:5686–5699

    Article  Google Scholar 

  5. Holton JR (1992) An introduction to dynamic meteorology. Academic, San Diego

    Google Scholar 

  6. Huntingford C, Cox PM (2000) An analogue model to derive additional climate change scenarios from existing GCM simulations. Clim Dynam 16:575–586

    Article  Google Scholar 

  7. Johns TC et al (2006) The new Hadley Centre climate model HadGEM1: evaluation of coupled simulations. J Clim 19:1327–1353

    Article  Google Scholar 

  8. Jones RG, Murphy JM, Noguer M, Keen AB (1997) Simulation of climate change over Europe using a nested regional climate model. II: Comparison of driving and regional model responses to a doubling of carbon dioxide. Quart J R Met Soc 123:265–292

    Google Scholar 

  9. Manabe S, Stouffer RJ, Spelman MJ, Bryan K (1991) Transient responses of a coupled ocean-atmosphere model to gradual changes of atmospheric CO2. Part I: annual mean response. J Clim 4:785–818

    Article  Google Scholar 

  10. Manabe S, Spelman MJ, Stouffer RJ (1992) Transient responses of a coupled ocean-atmosphere model to gradual changes of atmospheric CO2. Part II: seasonal response. J Clim 5:105–126

    Article  Google Scholar 

  11. Martin GM, Ringer MA, Pope VD, Jones A, Dearden C, Hinton TJ (2006) The physical properties of the atmosphere in the new Hadley Centre global environment model, HadGEM1. Part I: model description and global climatology. J Clim 19:1274–1301

    Article  Google Scholar 

  12. Murphy JM, Sexton DMH, Barnett DN, Jones GS, Webb MJ, Collins M (2004) Quantification of modelling uncertainties in a large ensemble of climate change simulations. Nature 430:768–772

    Article  Google Scholar 

  13. Rowell DP, Jones RG (2006) Causes and uncertainty of future summer drying over Europe. Clim Dynam 27:281–299

    Article  Google Scholar 

  14. Senior CA, Mitchell JFB (1993) Carbon dioxide and climate: the impact of cloud parameterization. J Clim 6:393–418

    Article  Google Scholar 

  15. Sutton RT, Dong B, Gregory JM (2007) Land/sea warming ratio in response to climate change: IPCC AR4 model results and comparison with observations. Geophys Res Lett 34:L02701

    Article  Google Scholar 

  16. Webb MJ et al (2006) On the contribution of local feedback mechanisms to the range of climate sensitivity in two GCM ensembles. Clim Dynam 27:17–38

    Article  Google Scholar 

  17. Williams KD, Senior CA, Mitchell JFB (2001) Transient climate change in the Hadley Centre models: the role of physical processes. J Clim 14:2659–2674

    Article  Google Scholar 

Download references

Acknowledgments

MJ, MW, DS and JG are supported by the UK Department for Environment, Food and Rural Affairs (Defra) contract number PECD/7/12/37. JG is supported by the National Centre for Atmospheric Science (NCAS). TJ is supported by the UK Government Meteorological Research (GMR) programme. We would like to thank the reviewers of the original submitted manuscript and Keith Shine for their useful comments. We acknowledge the modelling groups for providing their data for analysis for the AR4 and CFMIP, the Program for Climate Model Diagnosis and Intercomparison (PCMDI) for collecting and archiving the model output, and the JSC/CLIVAR Working Group on Coupled Modelling (WGCM) for organizing the model data analysis activity. The multi-model data archive is supported by the Office of Science, US Department of Energy.

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Correspondence to Manoj M. Joshi.

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Joshi, M.M., Gregory, J.M., Webb, M.J. et al. Mechanisms for the land/sea warming contrast exhibited by simulations of climate change. Clim Dyn 30, 455–465 (2008). https://doi.org/10.1007/s00382-007-0306-1

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Keywords

  • Climate change
  • Climate models
  • Surface temperature
  • Climate sensitivity