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On the Tropical Atlantic SST warm bias in the Kiel Climate Model

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Abstract

Most of the current coupled general circulation models show a strong warm bias in the eastern Tropical Atlantic. In this paper, various sensitivity experiments with the Kiel Climate Model (KCM) are described. A largely reduced warm bias and an improved seasonal cycle in the eastern Tropical Atlantic are simulated in one particular version of KCM. By comparing the stable and well-tested standard version with the sensitivity experiments and the modified version, mechanisms contributing to the reduction of the eastern Atlantic warm bias are identified and compared to what has been proposed in literature. The error in the spring and early summer zonal winds associated with erroneous zonal precipitation seems to be the key mechanism, and large-scale coupled ocean–atmosphere feedbacks play an important role in reducing the warm bias. Improved winds in boreal spring cause the summer cooling in the eastern Tropical Atlantic (ETA) via shoaling of the thermocline and increased upwelling, and hence reduced sea surface temperature (SST). Reduced SSTs in the summer suppress convection and favor the development of low-level cloud cover in the ETA region. Subsurface ocean structure is shown to be improved, and potentially influences the development of the bias. The strong warm bias along the southeastern coastline is related to underestimation of low-level cloud cover and the associated overestimation of surface shortwave radiation in the same region. Therefore, in addition to the primarily wind forced response at the equator both changes in surface shortwave radiation and outgoing longwave radiation contribute significantly to reduction of the warm bias from summer to fall.

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References

  • Breugem W-P, Chang P, Jang CJ, Mignot J, Hazeleger W (2008) Barrier layers and Tropical Atlantic SST biases in coupled GCMs. Tellus A 60(5):885–897

    Article  Google Scholar 

  • Carton JA, Giese BS (2008) A reanalysis of ocean climate using simple ocean data assimilation (SODA). Mon Wea Rev 136(8):2999–3017

    Article  Google Scholar 

  • Chang C-Y, Carton JA, Grodsky SA, Nigam S (2007) Seasonal climate of the Tropical Atlantic sector in the NCAR community climate system model 3: error structure and probable causes of errors. J Clim 20:1053–1070

    Article  Google Scholar 

  • Chang C-Y, Nigam S, Carton JA (2008) Origin of the springtime westerly bias in equatorial atlantic surface winds in the community atmosphere model version 3 (CAM3) simulation. J Clim 21(18):4766–4778

    Article  Google Scholar 

  • Collins W, Bitz C, Blackmon M, Bonan G, Bretherton C, Carton J, Chang P, Doney S, Hack J, Henderson T, Kiehl J, Large W, McKenna D, Santer B, Smith R (2006) The community climate system model version 3 (CCSM3). J Clim 19:2122–2143

    Article  Google Scholar 

  • Davey MK, Huddleston M, Sperber K, Braconnot P, Bryan F, Chen D, Colman R, Cooper C, Cubasch U, Delecluse P, DeWitt D, Fairhead L, Flato G, Gordon C, Hogan T, Ji M, Kimoto M, Kitoh A, Knutson T, Latif M, Treut HL, Li T, Manabe S, Mechoso C, Meehl G, Power S, Roeckner E, Terray L, Vintzileos A, Voss R, Wang B, Washington W, Yoshikawa I, Yu J, Yukimoto S, Zebiak S (2002) STOIC: a study of coupled model climatology and variability in tropical ocean regions. Clim Dyn 18:403–420

    Article  Google Scholar 

  • Ding H, Keenlyside N, Latif M (2009) Seasonal cycle in the upper Equatorial Atlantic Ocean. J Geophys Res 114(C9):C09016

    Article  Google Scholar 

  • Florenchie P, Lutjeharms JRE, Reason CJC, Masson S, Rouault M (2003) The source of Benguela Ninos in the South Atlantic Ocean. Geophys Res Lett 30(10):1505

    Article  Google Scholar 

  • Fu R, Genio AD, Rossow WB (1994) Influence of ocean surface conditions on atmospheric vertical thermodynamic structure and deep convection. J Clim 7:1092–1108

    Article  Google Scholar 

  • Gates WL (1992) AMIP: the atmospheric model intercomparison project. Bull Am Meteor Soc 73(12):1962–1970

    Article  Google Scholar 

  • Gordon CT, Rosati A, Gudgel R (2000) Tropical sensitivity of a coupled model to specified ISCCP low clouds. J Clim 13:2239–2260

    Article  Google Scholar 

  • Graf J, Sasaki C, Winn C, Liu WT, Tsai W (1998) NASA scatterometer experiment. Acta Astronaut 7–8:397–407

    Article  Google Scholar 

  • Hazeleger W, Haarsma R (2005) Sensitivity of Tropical Atlantic climate to mixing in a coupled ocean-atmosphere model. Clim Dyn 25(4):387–399

    Article  Google Scholar 

  • Hu Z, Huang B (2007) Physical processes associated with the Tropical Atlantic SST gradient during the anomalous evolution in the southeastern ocean. J Clim 20:3366–3378

    Article  Google Scholar 

  • Hu Z-Z, Huang B, Pegion K (2008) Low cloud error over the southeastern atlantic in the NCEP CFS and their association with lower-tropospheric stability and air-sea interaction. J Geophys Res 113:D12114

    Article  Google Scholar 

  • Huang B, Hu Z-Z, Jha B (2007) Evolution of model systematic errors in the Tropical Atlantic basin from coupled climate hindcasts. Clim Dyn 28(7–8):661–682

    Article  Google Scholar 

  • Hulme M, Doherty R, Ngara T, New M, Lister D (2001) African climate change: 1900–2100. Clim Res 17:145–168

    Article  Google Scholar 

  • Kalnay E, Kanamitsu M, Kistler R et al (1996) The NCEP/NCAR 40-year reanalysis project. Bull Am Meteor Soc 77:437–470

    Google Scholar 

  • Kara AB, Rochford PA, Hurlburt HE (2000) Efficient and accurate bulk parameterizations of air-sea fluxes for use in general circulation models. J Atmos Ocean Technol 17(10):1421–1438

    Article  Google Scholar 

  • Large WG, Danabasoglu G (2006) Attribution and impacts of upper-ocean biases in CCSM3. J Clim 19:2325–2346

    Article  Google Scholar 

  • Latif M, Park W, Ding H, Keenlyside N (2009) Internal and external north atlantic sector variability in the Kiel Climate Model. Meteor Z (accepted)

  • Lee S-K, Wang C (2008) Tropical Atlantic decadal oscillation and its potential impact on the equatorial atmosphere ocean dynamics: a simple model study. J Phys Oceanogr 38(1):192–212

    Article  Google Scholar 

  • Ma C, Mechoso C, Robertson A, Arakawa A (1996) Peruvian stratus clouds and the tropical pacific circulation: a coupled ocean-atmosphere GCM study. J Clim 9:1635–1645

    Article  Google Scholar 

  • Madec G (2008) NEMO ocean engine. Note du Pole de modelisation, Institut Pierre-Simon Laplace (IPSL) No 27. ISSN No 1288–1619

  • Miller M, Beljaars A, Palmer T (1992) The sensitivitiy of the ECMWF model to parameterization of evaporation from the tropical oceans. J Clim 5:418–434

    Article  Google Scholar 

  • Nigam S (1997) The annual warm to cold phase transition in the eastern equatorial pacific: diagnosis of the role of stratus cloud-top cooling. J Clim 10:2447–2467

    Article  Google Scholar 

  • Park W, Latif M (2008) Multidecadal and multicentennial variability of the meridional overturning circulation. Geophys Res Lett 35:L22703

    Article  Google Scholar 

  • Park W, Keenlyside N, Latif M, Stroeh A, Redler R, Roeckner E, Madec G (2009) Tropical pacific climate and its response to global warming in the Kiel Climate Model. J Clim 22:71–92

    Article  Google Scholar 

  • Polo I, Lazar A, Rodriguez-Fonseca B, Arnault S (2008) Oceanic Kelvin waves and Tropical Atlantic intraseasonal variability: 1. Kelvin wave characterization. J Geophys Res 113:C07009

    Article  Google Scholar 

  • Richter I, Xie S-P (2008) On the origin of equatorial atlantic biases in coupled general circulation models. Clim Dyn 31(5):587–598

    Article  Google Scholar 

  • Roeckner E, Bäuml G, Bonaventura L, Brokopf R, Esch M, Girogetta M, Hagemann S, Kirchner I, Kornblueh L, Manzini E, Rhodin A, Schlese U, Schulzweida U, Tompkins A (2003) The atmospheric general circulation model ECHAM 5, Part I, MPI Report 349:137p. Max-Planck-Institut für Meteorologie, Hamburg

  • Rossow WB, Schiffer RA (1991) ISCCP cloud data products. Bull Am Meteor Soc 72(1):2–20

    Article  Google Scholar 

  • Saha S, Nadiga S, Thiaw C, Wang J, Wang W, Zhang Q, Van den Dool HM, Pan HL, Moorthi S, Behringer D, Stokes D, Pena M, Lord S, White G, Ebisuzaki W, Peng P, Xie P (2006) The NCEP climate forecast system. J Clim 19(15):3483–3517

    Article  Google Scholar 

  • Seo H, Jochum M, Murtugudde R, Miller A (2006) Effect of ocean mesoscale variability on the mean state of Tropical Atlantic climate. Geophys Res Lett 33:L0960

    Article  Google Scholar 

  • Servain J (1991) Simple climatic indices for the Tropical Atlantic ocean and some applications. J Geophys Res 96(C8):15137–15146

    Article  Google Scholar 

  • Stockdale TN, Balmaseda M, Vidard A (2006) Tropical Atlantic SST prediction with coupled ocean-atmosphere GCMs. J Clim 19:6047–6061

    Article  Google Scholar 

  • Valcke S, Guilyardi E, Larsson C (2006) PRISM and ENES: a European approach to earth system modelling. Concurrency Comput Pract Expert 18(2):231–245

    Article  Google Scholar 

  • Xie P, Arkin P (1997) Global precipitation: a 17-year monthly analysis based on gauge observations, satellite estimates, and numerical model outputs. Bull Am Meteor Soc 78(11):2539–2558

    Article  Google Scholar 

  • Yu J-Y, Mechoso CR (1999) A discussion on the errors in the surface heat fluxes simulated by a coupled GCMs. J Clim 12:416–426

    Article  Google Scholar 

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Acknowledgments

The authors thank J.-J. Luo for the discussion of the bias problem in CGCMs that provided good ideas for this study. We also would like to thank A. Biastoch for providing the forced ocean run data as well as the input of two reviewers that helped to improve the manuscript. The authors wish to acknowledge use of the Ferret program for analysis and graphics in this paper. This work was supported by the Nordatlantik project of BMBF and the AMMA project of the European Union.

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  1. Leibniz Institute of Marine Sciences, Düsternbrooker Weg 20, 24105, Kiel, Germany

    Sebastian Wahl, Mojib Latif, Wonsun Park & Noel Keenlyside

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  1. Sebastian Wahl
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  2. Mojib Latif
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  3. Wonsun Park
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  4. Noel Keenlyside
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Correspondence to Sebastian Wahl.

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Wahl, S., Latif, M., Park, W. et al. On the Tropical Atlantic SST warm bias in the Kiel Climate Model. Clim Dyn 36, 891–906 (2011). https://doi.org/10.1007/s00382-009-0690-9

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  • DOI: https://doi.org/10.1007/s00382-009-0690-9

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