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  • Bond, N. A., , and G. A. Vecchi, 2003: The influence of the Madden– Julian oscillation on precipitation in Oregon and Washington. Wea. Forecasting, 18 , 600–613.

    • Search Google Scholar
    • Export Citation

  • Bretherton, C. S., , and A. H. Sobel, 2002: A simple model of a convectively coupled Walker circulation using the weak temperature gradient approximation. J. Climate, 15 , 2907–2920.

    • Search Google Scholar
    • Export Citation

  • Cronin, M. F., , and M. J. McPhaden, 1997: The upper ocean heat balance in the western equatorial Pacific warm pool during September–December 1992. J. Geophys. Res, 102 , 27567–27587.

    • Search Google Scholar
    • Export Citation

  • Emanuel, K. A., 1987: An air–sea interaction model of intraseasonal oscillations in the tropics. J. Atmos. Sci, 44 , 2324–2340.

  • Fasullo, J., , and P. J. Webster, 1999: Warm pool SST variability in relation to the surface energy balance. J. Climate, 12 , 1292–1305.

  • Fasullo, J., , and P. J. Webster, 2000: Atmospheric and surface variations during westerly wind bursts in the tropical western Pacific. Quart. J. Roy. Meteor. Soc, 126 , 899–924.

    • Search Google Scholar
    • Export Citation

  • Flatau, M., , P. J. Flatau, , P. Phoebus, , and P. P. Niiler, 1997: The feedback between equatorial convection and local radiative and evaporative processes: The implications for intraseasonal oscillations. J. Atmos. Sci, 54 , 2373–2386.

    • Search Google Scholar
    • Export Citation

  • Grabowski, W. W., 2003: MJO-like coherent structure: Sensitivity simulations using the Cloud-Resolving Convection Parameterization (CRCP). J. Atmos. Sci, 60 , 847–864.

    • Search Google Scholar
    • Export Citation

  • Gualdi, S., , A. Navarra, , and M. Fischer, 1999: The tropical intraseasonal oscillation in a coupled ocean–atmosphere general circulation model. Geophys. Res. Lett, 26 , 2973–2976.

    • Search Google Scholar
    • Export Citation

  • Hack, J. J., 1994: Parameterization of moist convection in the National Center for Atmospheric Research Community Climate Model (CCM2). J. Geophys. Res, 99 , 5551–5568.

    • Search Google Scholar
    • Export Citation

  • Hansen, J., , A. Lacis, , D. Rind, , G. Russell, , P. Stone, , I. Fung, , R. Ruedy, , and J. Lerner, 1984: Climate sensitivity: Analysis of feedback mechanisms in climate processes and sensitivity. Climate Processes and Climate Sensitivity, Geophys. Monogr., No. 29, Amer. Geophys. Union, 130–163.

    • Search Google Scholar
    • Export Citation

  • Harrison, E. F., , P. Minnis, , B. R. Barkstrom, , V. Ramanathan, , R. D. Cess, , and G. G. Gibson, 1990: Seasonal variation of cloud-radiative forcing derived from the Earth Radiation Budget Experiment. J. Geophys. Res, 95 , 18687–18703.

    • Search Google Scholar
    • Export Citation

  • Hartmann, D. L., , L. A. Moy, , and Q. Fu, 2001: Tropical convection and the energy balance at the top of the atmosphere. J. Climate, 14 , 4495–4511.

    • Search Google Scholar
    • Export Citation

  • Hendon, H. H., , and M. L. Salby, 1994: The life cycle of the Madden– Julian oscillation. J. Atmos. Sci, 51 , 2225–2237.

  • Hendon, H. H., , and J. Glick, 1997: Intraseasonal air–sea interaction in the tropical Indian and Pacific Oceans. J. Climate, 10 , 647–661.

    • Search Google Scholar
    • Export Citation

  • Inness, P. M., , and J. M. Slingo, 2003: Simulation of the Madden– Julian oscillation in a coupled general circulation model. Part I: Comparison with observations and an atmosphere-only GCM. J. Climate, 16 , 345–364.

    • Search Google Scholar
    • Export Citation

  • Jones, C., , and B. C. Weare, 1996: The role of low-level moisture convergence and ocean latent heat fluxes in the Madden–Julian oscillation: An observational analysis using ISCCP data and ECMWF analyses. J. Climate, 9 , 3086–3104.

    • Search Google Scholar
    • Export Citation

  • Jones, C., , D. E. Waliser, , and C. Gautier, 1998: The influence of the Madden–Julian oscillation on ocean surface heat fluxes and sea surface temperature. J. Climate, 11 , 1057–1072.

    • Search Google Scholar
    • Export Citation

  • Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-Year Reanalysis Project. Bull. Amer. Meteor. Soc, 77 , 437–471.

  • Kawamura, R., 1988: Intraseasonal variability of sea surface temperature over the tropical western Pacific. J. Meteor. Soc. Japan, 66 , 1007–1012.

    • Search Google Scholar
    • Export Citation

  • Kemball-Cook, S., , B. Wang, , and X. Fu, 2002: Simulation of the intraseasonal oscillation in the ECHAM-4 model: The impact of coupling with an ocean model. J. Atmos. Sci, 59 , 1433–1453.

    • Search Google Scholar
    • Export Citation

  • Kiehl, J. T., 1994: On the observed near cancellation between longwave and shortwave cloud-forcing in tropical regions. J. Climate, 7 , 559–565.

    • Search Google Scholar
    • Export Citation

  • Kiehl, J. T., , and P. R. Gent, 2004: The Community Climate System Model, version 2. J. Climate, 17 , 3666–3682.

  • Kiehl, J. T., , J. J. Hack, , G. B. Bonan, , B. A. Boville, , D. L. Williamson, , and P. J. Rasch, 1998a: The National Center for Atmospheric Research Community Climate Model: CCM3. J. Climate, 11 , 1131–1149.

    • Search Google Scholar
    • Export Citation

  • Kiehl, J. T., , J. J. Hack, , and J. W. Hurrell, 1998b: The energy budget of the NCAR Community Climate Model: CCM3. J. Climate, 11 , 1151–1178.

    • Search Google Scholar
    • Export Citation

  • Krishnamurti, T. N., , D. K. Oosterhof, , and A. V. Mehta, 1988: Air– sea interaction on the time scale of 30–50 days. J. Atmos. Sci, 45 , 1304–1322.

    • Search Google Scholar
    • Export Citation

  • Lau, K-M., , and C-H. Sui, 1997: Mechanisms of short-term sea surface temperature regulation: Observations during TOGA COARE. J. Climate, 10 , 465–472.

    • Search Google Scholar
    • Export Citation

  • Lee, M. I., , I-S. Kang, , J-M. Kim, , and B. E. Mapes, 2001: Influence of cloud–radiation interaction on simulating the tropical intraseasonal oscillation in an atmospheric general circulation model. J. Geophys. Res, 106 , 14219–14233.

    • Search Google Scholar
    • Export Citation

  • Lin, J., , and B. E. Mapes, 2004: Radiation budget of the tropical intraseasonal oscillations. J. Atmos. Sci, 61 , 2050–2062.

  • Lin, J., , J. D. Neelin, , and N. Zeng, 2000: Maintenance of tropical intraseasonal variability: Impact of wind–evaporation feedback and midlatitude storms. J. Atmos. Sci, 57 , 2793–2823.

    • Search Google Scholar
    • Export Citation

  • Lin, X., , and R. H. Johnson, 1996: Kinematic and thermodynamic characteristics of the flow over the western Pacific warm pool during TOGA COARE. J. Atmos. Sci, 53 , 695–715.

    • Search Google Scholar
    • Export Citation

  • Lindzen, R. S., , and S. Nigam, 1987: On the role of sea surface temperature gradients in forcing low-level winds and convergence in the tropics. J. Atmos. Sci, 44 , 2418–2436.

    • Search Google Scholar
    • Export Citation

  • Madden, R. A., , and P. R. Julian, 1994: Observations of the 40–50-day tropical oscillation—A review. Mon. Wea. Rev, 122 , 814–837.

  • Majda, A. J., , and R. Klein, 2003: Systematic multiscale models for the Tropics. J. Atmos. Sci, 60 , 393–408.

  • Maloney, E. D., , and D. L. Hartmann, 1998: Frictional moisture convergence in a composite life cycle of the Madden–Julian oscillation. J. Climate, 11 , 2387–2403.

    • Search Google Scholar
    • Export Citation

  • Maloney, E. D., , and D. L. Hartmann, 2001: The sensitivity of intraseasonal variability in the NCAR CCM3 to changes in convective parameterization. J. Climate, 14 , 2015–2034.

    • Search Google Scholar
    • Export Citation

  • Maloney, E. D., , and J. T. Kiehl, 2002: Intraseasonal eastern Pacific precipitation and SST variations in a GCM coupled to a slab ocean model. J. Climate, 15 , 2989–3007.

    • Search Google Scholar
    • Export Citation

  • Maloney, E. D., , and S. K. Esbensen, 2003: The amplification of east Pacific Madden–Julian oscillation convection and wind anomalies during June–November. J. Climate, 16 , 3482–3497.

    • Search Google Scholar
    • Export Citation

  • Moorthi, S., , and M. J. Suarez, 1992: Relaxed Arakawa–Schubert: A parameterization of moist convection for general circulation models. Mon. Wea. Rev, 120 , 978–1002.

    • Search Google Scholar
    • Export Citation

  • Neelin, J. D., , and I. M. Held, 1987: Modeling tropical convergence based on the moist static energy budget. Mon. Wea. Rev, 115 , 3–12.

  • Neelin, J. D., , and N. Zeng, 2000: A quasi-equilibrium tropical circulation model formulation. J. Atmos. Sci, 57 , 1741–1766.

  • Neelin, J. D., , I. M. Held, , and K. H. Cook, 1987: Evaporation–wind feedback and low-frequency variability in the tropical atmosphere. J. Atmos. Sci, 44 , 2341–2348.

    • Search Google Scholar
    • Export Citation

  • Ramanathan, V., , R. D. Cess, , E. F. Harrison, , P. Minnis, , B. R. Barkstrom, , E. Ahmad, , and D. Hartmann, 1989: Cloud-radiative forcing and climate: Results from the Earth Radiation Budget Experiment. Science, 243 , 57–63.

    • Search Google Scholar
    • Export Citation

  • Randall, D., , M. Khairoutdinov, , A. Arakawa, , and W. Grabowski, 2003: Breaking the cloud-parameterization deadlock. Bull. Amer. Meteor. Soc, 84 , 1547–1564.

    • Search Google Scholar
    • Export Citation

  • Raymond, D. J., 2001: A new model of the Madden–Julian oscillation. J. Atmos. Sci, 58 , 2807–2819.

  • Shinoda, T., , H. H. Hendon, , and J. Glick, 1998: Intraseasonal variability of surface fluxes and sea surface temperatures in the tropical western Pacific and Indian Oceans. J. Climate, 11 , 1685–1702.

    • Search Google Scholar
    • Export Citation

  • Sobel, A. H., , and C. S. Bretherton, 2000: Modeling tropical precipitation in a single column. J. Climate, 13 , 4378–4392.

  • Sobel, A. H., , and H. Gildor, 2003: A simple time-dependent model of SST hotspots. J. Climate, 16 , 3978–3992.

  • Sobel, A. H., , J. Nilsson, , and L. M. Polvani, 2001: The weak temperature gradient approximation and balanced tropical moisture waves. J. Atmos. Sci, 58 , 3650–3665.

    • Search Google Scholar
    • Export Citation

  • Straub, K. H., , and G. N. Kiladis, 2003: Interactions between the boreal summer intraseasonal oscillation and higher frequency tropical wave activity. Mon. Wea. Rev, 131 , 781–796.

    • Search Google Scholar
    • Export Citation

  • Sud, Y. C., , and A. Molod, 1988: The roles of dry convection, cloud– radiation feedback processes and the influence of recent improvements in the parameterization of convection in the GLA GCM. Mon. Wea. Rev, 116 , 2366–2387.

    • Search Google Scholar
    • Export Citation

  • Sud, Y. C., , G. K. Walker, , and K-M. Lau, 1999: Mechanisms regulating sea-surface temperatures and deep convection in the tropics. Geophys. Res. Lett, 26 , 1019–1022.

    • Search Google Scholar
    • Export Citation

  • Waliser, D. E., 1996: Formation and limiting mechanisms for very high sea surface temperatures: Linking the dynamics and thermodynamics. J. Climate, 9 , 161–188.

    • Search Google Scholar
    • Export Citation

  • Waliser, D. E., , K. M. Lau, , and J-H. Kim, 1999: The influence of coupled sea surface temperatures on the Madden–Julian oscillation: A model perturbation experiment. J. Atmos. Sci, 56 , 333–358.

    • Search Google Scholar
    • Export Citation

  • Wang, B., , and X. Xie, 1998: Coupled modes of the warm pool climate system. Part I: The role of air–sea interaction in maintaining the Madden–Julian oscillation. J. Climate, 11 , 2116–2135.

    • Search Google Scholar
    • Export Citation

  • Watterson, I. G., 2002: The sensitivity of subannual and intraseasonal tropical variability to model ocean mixed layer depth. J. Geophys. Res.,107, 4020, doi:10.1029/2001JD000671.

    • Search Google Scholar
    • Export Citation

  • Weare, B. C., 2003: Composite singular value decomposition analysis of moisture variations associated with the Madden–Julian oscillation. J. Climate, 16 , 3779–3792.

    • Search Google Scholar
    • Export Citation

  • Weare, B. C., , and J. S. Nasstrom, 1982: Examples of extended empirical orthogonal function analysis. Mon. Wea. Rev, 110 , 481–485.

  • Weller, R. A., , and S. P. Anderson, 1996: Surface meteorology and air–sea fluxes in the western equatorial Pacific warm pool during the TOGA Coupled Ocean–Atmosphere Response Experiment. J. Climate, 9 , 1959–1990.

    • Search Google Scholar
    • Export Citation

  • Wheeler, M., , and G. N. Kiladis, 1999: Convectively coupled equatorial waves: Analysis of clouds and temperature in the wavenumber–frequency domain. J. Atmos. Sci, 56 , 374–399.

    • Search Google Scholar
    • Export Citation

  • Woolnough, S. J., , J. M. Slingo, , and B. J. Hoskins, 2000: The relationship between convection and sea surface temperatures on intraseasonal timescales. J. Climate, 13 , 2086–2104.

    • Search Google Scholar
    • Export Citation

  • Xie, P., , and P. A. Arkin, 1996: Analyses of global monthly precipitation using gauge observations, satellite estimates, and numerical model predictions. J. Climate, 9 , 840–858.

    • Search Google Scholar
    • Export Citation

  • Xie, S-P., , A. Kubokawa, , and K. Hanawa, 1993a: Evaporation–wind feedback and the organizing of tropical convection on the planetary scale. Part I: Quasi-linear instability. J. Atmos. Sci, 50 , 3873–3883.

    • Search Google Scholar
    • Export Citation

  • Xie, S-P., , A. Kubokawa, , and K. Hanawa, 1993b: Evaporation–wind feedback and the organizing of tropical convection on the planetary scale. Part II: Nonlinear evolution. J. Atmos. Sci, 50 , 3884–3893.

    • Search Google Scholar
    • Export Citation

  • Zhang, C., 1996: Atmospheric intraseasonal variability at the surface in the tropical western Pacific Ocean. J. Atmos. Sci, 53 , 739–758.

    • Search Google Scholar
    • Export Citation

  • Zhang, C., , and N. A. McFarlane, 1995: Sensitivity of climate simulations to the parameterization of cumulus convection in the Canadian Climate Centre General Circulation Model. Atmos.–Ocean, 33 , 407–446.

    • Search Google Scholar
    • Export Citation

  • Zhang, C., , and H. H. Hendon, 1997: Propagating and standing components of the intraseasonal oscillation in tropical convection. J. Atmos. Sci, 54 , 741–752.

    • Search Google Scholar
    • Export Citation

  • Zhang, C., , and M. J. McPhaden, 2000: Intraseasonal surface cooling in the equatorial western Pacific. J. Climate, 13 , 2261–2276.

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Surface Fluxes and Ocean Coupling in the Tropical Intraseasonal Oscillation

Eric D. Maloney1 and Adam H. Sobel2
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  • 1 College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, Oregon
  • | 2 Department of Applied Physics and Applied Mathematics, and Department of Earth and Environmental Sciences,Columbia University, New York, New York
Print Publication:
15 Nov 2004
DOI:
https://doi.org/10.1175/JCLI-3212.1
Page(s):
4368–4386
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Abstract

Sensitivity of tropical intraseasonal variability to mixed layer depth is examined in the modified National Center for Atmospheric Research Community Atmosphere Model 2.0.1 (CAM), with relaxed Arakawa–Schubert convection, coupled to a slab ocean model (SOM) whose mixed layer depth is fixed and geographically uniform, but varies from one experiment to the next. Intraseasonal west Pacific precipitation variations during boreal winter are enhanced relative to a fixed-SST (infinite mixed layer depth) simulation for mixed layer depths from 5 to 50 m, with a maximum at 20 m [interestingly, near the observed value in the regions where the Madden– Julian oscillation (MJO) is active], but are strongly diminished in the 2-m depth simulation. This nonmonotonicity of intraseasonal precipitation variance with respect to mixed layer depth was predicted by Sobel and Gildor using a highly idealized model. Further experiments with the same idealized model help to interpret results derived from the modified NCAR CAM.

A sensitivity study shows that the convection–surface flux feedback [wind-induced surface heat exchange (WISHE)] is important to the intraseasonal variability in the CAM. This helps to explain the behavior of the 2-m SOM simulation and the agreement with the idealized model. Although intraseasonal SST variations are stronger in the 2-m SOM simulation than in any of the other simulations, these SST variations are phased in such a way as to diminish the amplitude of equatorial latent heat flux variations. Reducing the mixed layer depth is thus nearly equivalent to eliminating WISHE, which in this model reduces intraseasonal variability. The WISHE mechanism in the model is nonlinear and occurs in a region of mean low-level westerlies.

Since a very shallow mixed layer is effectively similar to wet land, it is suggested that the mechanism described here may explain the local minimum in MJO amplitude observed over the Maritime Continent region.

Corresponding author address: Eric D. Maloney, College of Oceanic and Atmospheric Sciences, Oregon State University, 104 Ocean Admin. Bldg., Corvallis, OR 97331-5503. Email: maloney@coas.oregonstate.edu

Abstract

Sensitivity of tropical intraseasonal variability to mixed layer depth is examined in the modified National Center for Atmospheric Research Community Atmosphere Model 2.0.1 (CAM), with relaxed Arakawa–Schubert convection, coupled to a slab ocean model (SOM) whose mixed layer depth is fixed and geographically uniform, but varies from one experiment to the next. Intraseasonal west Pacific precipitation variations during boreal winter are enhanced relative to a fixed-SST (infinite mixed layer depth) simulation for mixed layer depths from 5 to 50 m, with a maximum at 20 m [interestingly, near the observed value in the regions where the Madden– Julian oscillation (MJO) is active], but are strongly diminished in the 2-m depth simulation. This nonmonotonicity of intraseasonal precipitation variance with respect to mixed layer depth was predicted by Sobel and Gildor using a highly idealized model. Further experiments with the same idealized model help to interpret results derived from the modified NCAR CAM.

A sensitivity study shows that the convection–surface flux feedback [wind-induced surface heat exchange (WISHE)] is important to the intraseasonal variability in the CAM. This helps to explain the behavior of the 2-m SOM simulation and the agreement with the idealized model. Although intraseasonal SST variations are stronger in the 2-m SOM simulation than in any of the other simulations, these SST variations are phased in such a way as to diminish the amplitude of equatorial latent heat flux variations. Reducing the mixed layer depth is thus nearly equivalent to eliminating WISHE, which in this model reduces intraseasonal variability. The WISHE mechanism in the model is nonlinear and occurs in a region of mean low-level westerlies.

Since a very shallow mixed layer is effectively similar to wet land, it is suggested that the mechanism described here may explain the local minimum in MJO amplitude observed over the Maritime Continent region.

Corresponding author address: Eric D. Maloney, College of Oceanic and Atmospheric Sciences, Oregon State University, 104 Ocean Admin. Bldg., Corvallis, OR 97331-5503. Email: maloney@coas.oregonstate.edu

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