The Tropical Ocean Response to a Change in Solar Forcing

David G. DeWitt Center for Ocean–Land–Atmosphere Studies, Calverton, Maryland

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Edwin K. Schneider Center for Ocean–Land–Atmosphere Studies, Calverton, Maryland

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Abstract

Changes in the tropical oceans caused by a shift of 6 months in the date of perihelion are examined using a coupled atmosphere–ocean general circulation model (GCM). The changes in the annual cycle of sea surface temperature (SST) near the equator are described, and the mechanism for the changes is diagnosed. The GCM results are diagnosed using the ocean component model forced by the time mean fluxes from the coupled integration. This diagnosis shows that the changes in the annual cycle of near-equatorial SST are caused by different mechanisms in different regions. An extensive analysis of the changes in the eastern Pacific is given because of the importance of this region in modulating the global climate through teleconnections associated with ENSO.

In the eastern Pacific, the change in the annual cycle of SST is found to be primarily due to zonal wind stress differences. The zonal wind stress differences are caused for the most part by changes in the precipitation distribution. The changes in the precipitation distribution are consistent with being caused by changes in both the low-level convergence forced by the surface temperature gradients and changes in the local evaporation. The physical process responsible for the change in low-level zonal wind and convergence are diagnosed using a steady-state linearized version of the atmospheric model that is forced by time mean fields from the coupled model.

Interannual variability of eastern Pacific (Niño-3) SST under the modified solar forcing is found to have an amplitude and period similar to those observed in modern times. The only major difference in the interannual variability of tropical Pacific SST is found to be the timing of SST anomalies. This occurs because the interannual SST variability in the tropical eastern Pacific is phase locked to the annual cycle of SST, whose phase is itself dependent on the solar forcing.

Corresponding author address: Dr. David G. DeWitt, Center for Ocean–Land–Atmosphere Studies, 4041 Powder Mill Road, Suite 302, Calverton, MD 20705-3106.

Abstract

Changes in the tropical oceans caused by a shift of 6 months in the date of perihelion are examined using a coupled atmosphere–ocean general circulation model (GCM). The changes in the annual cycle of sea surface temperature (SST) near the equator are described, and the mechanism for the changes is diagnosed. The GCM results are diagnosed using the ocean component model forced by the time mean fluxes from the coupled integration. This diagnosis shows that the changes in the annual cycle of near-equatorial SST are caused by different mechanisms in different regions. An extensive analysis of the changes in the eastern Pacific is given because of the importance of this region in modulating the global climate through teleconnections associated with ENSO.

In the eastern Pacific, the change in the annual cycle of SST is found to be primarily due to zonal wind stress differences. The zonal wind stress differences are caused for the most part by changes in the precipitation distribution. The changes in the precipitation distribution are consistent with being caused by changes in both the low-level convergence forced by the surface temperature gradients and changes in the local evaporation. The physical process responsible for the change in low-level zonal wind and convergence are diagnosed using a steady-state linearized version of the atmospheric model that is forced by time mean fields from the coupled model.

Interannual variability of eastern Pacific (Niño-3) SST under the modified solar forcing is found to have an amplitude and period similar to those observed in modern times. The only major difference in the interannual variability of tropical Pacific SST is found to be the timing of SST anomalies. This occurs because the interannual SST variability in the tropical eastern Pacific is phase locked to the annual cycle of SST, whose phase is itself dependent on the solar forcing.

Corresponding author address: Dr. David G. DeWitt, Center for Ocean–Land–Atmosphere Studies, 4041 Powder Mill Road, Suite 302, Calverton, MD 20705-3106.

Save
  • Alpert, J. C., M. Kanamitsu, P. M. Caplan, J. G. Sela, G. H. White, and E. Kalnay, 1988: Mountain induced gravity wave drag parameterization in the NMC medium-range forecast model. Proc. Eighth Conf. on Numerical Weather Prediction, Baltimore, MD, Amer. Meteor. Soc., 726–733.

  • Battisti, D. S., and A. C. Hirst, 1989: Interannual variability in a tropical atmosphere–ocean model: Influence of the basic state, ocean geometry, and nonlinearity. J. Atmos. Sci.,46, 1687–1712.

  • Behringer, D. W., M. Ji., and A. Leetma, 1998: An improved coupled model for ENSO prediction and implications for ocean initialization. Part I: The ocean data assimilation system. Mon. Wea. Rev.,126, 1013–1021.

  • Berger, A., and M. F. Loutre, 1991: Insolation values for the climate of the last 10 million years. Quat. Sci. Rev.,10, 297–317.

  • Campana, K. A., and M. Kanamitsu, 1988: Surface boundary data. Documentation of the Research Version of the NMC Medium Range Forecasting Model, National Meteorological Center Development Division, 236 pp. [Available from NCEP, World Weather Building, 5200 Auth Rd., Camp Springs, MD 20746.].

  • Chang, P., 1993: Seasonal cycle of sea surface temperature and mixed layer heat budget in the tropical Pacific ocean. Geophys. Res. Lett.,20, 2079–2082.

  • Chen, D., A. J. Busalacchi, and L. M. Rothstein, 1994: The roles of vertical mixing, solar radiation, and wind stress in a model simulation of the sea surface temperature seasonal cycle in the tropical Pacific Ocean. J. Geophys. Res.,99, 20 345–20 359.

  • Davies, R., 1982: Documentation of the solar radiation parameterization in the GLAS climate model. NASA Tech. Memo. 83961, 57 pp.

  • DeWitt, D. G., 1996: The effect of the cumulus convection on the climate of the COLA general circulation model. COLA Tech. Memo. 27, 43 pp. [Available from Center for Ocean–Land–Atmosphere Studies, 4041 Powder Mill Rd Suite 302, Calverton, MD 20705–3106.].

  • ——, and E. K. Schneider, 1997: The Earth radiation budget as simulated by the COLA GCM. COLA Tech. Memo. 35, 33 pp. [Available from Center for Ocean–Land–Atmosphere Studies, 4041 Powder Mill Rd Suite 302, Calverton, MD 20705–3106.].

  • ——, and ——, 1999: On the processes determining the annual cycle of equatorial sea surface temperature: A coupled general circulation model perspective. Mon. Wea. Rev.,127, 381–395.

  • ——, ——, and A. D. Vernekar, 1996: Factors maintaining the zonally asymmetric precipitation distribution and low-level flow in the Tropics of at atmospheric general circulation model: Diagnostic studies. J. Atmos. Sci.,53, 2247–2263.

  • ECMWF Research Department, 1988: Research manual 3. ECMWF Forecast Model Physical Parameterization, European Centre for Medium-Range Weather Forecasts, Shinfield Park, Reading, 56 pp.

  • Fennessy, M. J., and Coauthors, 1994: The simulated Indian Monsoon: A GCM sensitivity study. J. Climate,7, 33–43.

  • Gill, A. E., 1980: Some simple solutions for heat induced tropical circulation. Quart. J. Roy. Meteor. Soc.,106, 447–462.

  • Gu, D., and S. G. H. Philander, 1997: Interdecadal climate fluctuations that depend on exchanges between the tropics and extratropics. Science,275, 805–807.

  • Harshvardhan, R. Davies, D. A. Randall, and T. G. Corsetti, 1987: A fast radiation parameterization for atmospheric circulation models. J. Geophys. Res.,92, 1009–1016.

  • Hewitt, C. D., and J. F. B. Mitchell, 1998: A fully coupled GCM simulation of the climate of the mid-Holocene. Geophys. Res. Lett.,25, 361–364.

  • Ji, M., A. Leetma, and J. Derber, 1995: An ocean analysis system for seasonal to interannual climate studies. Mon. Wea. Rev.,123, 460–481.

  • Kiehl, J. T., J. J. Hack, and B. P. Briegleb, 1994: The simulated earth radiation budget of the National Center for Atmospheric Research community climate model CCM2 and comparisons with the Earth Radiation Budget Experiment (ERBE). J. Geophys. Res.,99, 20 815–20 827.

  • ——, B. Boville, B. Briegleb, J. Hack, P. Rasch, and D. Williamson, 1996: Description of the NCAR Community Model (CCM3). NCAR Tech. Note NCAR/TN−420+STR, Boulder, Colorado, 152 pp.

  • Kinter, J. L., III, J. Shukla, L. Marx, and E. K. Schneider, 1988: A simulation of the winter and summer circulations with the NMC global spectral model. J. Atmos. Sci.,45, 2486–2522.

  • Koberle, C., and S. G. H. Philander, 1994: On the processes that control seasonal variations of sea surface temperatures in the tropical Pacific Ocean. Tellus,46A, 481–496.

  • Kutzbach, J. E., and B. L. Otto-Bleisner, 1982: The sensitivity of the African-Asian monsoonal climate to orbital parameter changes for 9000 years B. P. in a low resolution general circulation model. J. Atmos. Sci.,39, 1177–1188.

  • ——, and R. G. Gallimore, 1988: Sensitivity of a coupled atmosphere/mixed layer ocean model to changes in orbital forcing at 9000 years BP. J. Geophys. Res.,93, 803–821.

  • Lacis, A. A., and J. E. Hansen, 1974: A parameterization for the absorption of solar radiation in the earth’s atmosphere. J. Atmos. Sci.,32, 118–133.

  • Levitus, S., 1982: Climatological Atlas of the World Ocean. NOAA Professional Paper 13, 173 pp. and 17 microfiche.

  • Li, T., and S. G. H. Philander, 1996: On the annual cycle of the eastern equatorial Pacific. J. Climate,9, 2986–2998.

  • 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.

  • Mechoso, C. R., and Coauthors, 1995: The seasonal cycle over the tropical Pacific in coupled ocean–atmosphere general circulation models. Mon. Wea. Rev.,123, 2825–2838.

  • Mellor, G. L., and T. Yamada, 1982: Development of a turbulence closure model for geophysical fluid processes. Rev. Geophys. Space. Phys.,20, 851–875.

  • Mitchell, J. F. B., N. S. Grahame, and K. J. Needham, 1988: Climate simulations for 9000 years before present: Seasonal variations and effect of the Laurentide ice sheet. J. Geophys. Res.,93, 8283–8303.

  • Miyakoda, K., and J. Sirutis, 1977: Comparative integrations of global models with various parameterized processes of subgrid scale vertical transports. Beitr. Phys. Atmos.,50, 445–487.

  • Monin, A. S., and A. M. Obukhov, 1954: Basic laws of turbulent mixing in the ground layer of the atmosphere. Akad. Nauk SSSR Geofiz. Inst. Tr.,151, 63–187.

  • 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.

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

  • Otto-Bliesner, B. L., 1999: El Nino/La Nina and Sahel precipitation during the middle Holocene. Geophys. Res. Lett.,26, 87–90.

  • Pacanowski, R. C., 1995: MOM 2 Documentation, User’s Guide and Reference Manual. GFDL Ocean Tech. Rep. 3, 232 pp. [Available from U.S. Department of Commerce, GFDL, P.O. Box 308, Princeton, NJ 08542-0308.].

  • ——, and S. G. H. Philander, 1981: Parameterization of the vertical mixing in numerical models of tropical oceans. J. Phys. Oceanogr.,11, 1443–1451.

  • Paltridge, G. W., and C. M. R. Platt, 1976: Radiative Processes in Meteorology and Climatology. Elsevier, 318 pp.

  • Parker, D. E., M. Jackson, and E. B. Horton, 1995: The GISST2.2 sea surface temperature and sea-ice climatology. Hadley Centre Clim. Res. Tech. Note 63, 32 pp. [Available from Directory of the Hadley Center, United Kingdom Meteorological Office, Bracknell, Berkshire RG12 2SY, United Kingdom.].

  • Phillips, N. A., 1957: A coordinate system having some special advantages for numerical forecasting. J. Meteor.,14, 184–185.

  • Phillipps, P. J., and I. M. Held, 1994: The response to orbital perturbations in an atmospheric model coupled to a slab ocean. J. Climate,7, 767–782.

  • Rasmusson, E. M., and T. H. Carpenter, 1982: Variations in tropical sea surface temperature and surface wind fields associated with the Southern Oscillation/El Nino. Mon. Wea. Rev.,110, 354–384.

  • Reynolds, R. W., 1988: A real time global sea surface temperature analysis. J. Climate,1, 75–86.

  • Rosati, A., and K. Miyakoda, 1988: A general circulation model for upper ocean simulation. J. Phys. Oceanogr.,18, 1601–1626.

  • Sato, N., P. J. Sellers, D. A. Randall, E. K. Schneider, J. Shukla, J. L. Kinter, Y.-T. Hou, and E. Albertazzi, 1989a: Effects of implementing the simple biosphere model (SiB) in a general circulation model. J. Atmos. Sci.,46, 2752–2782.

  • ——, ——, ——, ——, ——, ——, ——, and ——, 1989b: Implementing the simple biosphere model (SiB) in a general circulation model: Methodology and results. NASA Contractor Report, Rep. NASA CR-185509, 76 pp. [Available from National Technical Information Service, Springfield, VA 22161.].

  • Schneider, E. K., 1989: A method for direct solution of a steady linearized spectral general circulation model. Mon. Wea. Rev.,117, 2137–2141.

  • ——, 1990: Linear diagnosis of stationary waves in a general circulation model. J. Atmos. Sci.,47, 2925–2952.

  • ——, and R. S. Lindzen, 1976: The influence of stable stratification on the thermally driven tropical boundary layer. J. Atmos. Sci.,33, 1301–1307.

  • ——, and ——, 1977: Axially symmetric steady-state models of the basic state for instability and climate studies. Part I: Linearized calculations. J. Atmos. Sci.,34, 263–279.

  • ——, and J. L. Kinter III, 1994: An examination of internally generated variability in long climate simulations. Climate Dyn.,10, 181–204.

  • ——, and Z. Zhu, 1998: Sensitivity of the simulated annual cycle of sea surface temperature in the equatorial Pacific to sunlight penetration. J. Climate,11, 1932–1950.

  • ——, B. Huang, and J. Shukla, 1995: Ocean wave dynamics and El Nino. J. Climate,8, 2415–2439.

  • Schopf, P. S., and M. J. Suarez, 1988: Vacillations in a coupled ocean-atmosphere model. J. Atmos. Sci.,45, 549–566.

  • Sela, J. G., 1980: Spectral modeling at the National Meteorological Center. Mon. Wea. Rev.,108, 1279–1292.

  • Sellers, P. J., Y. Mintz, Y. C. Sud, and A. Dalcher, 1986: A Simple Biosphere Model (SiB) for use within general circulation models. J. Atmos. Sci.,43, 505–531.

  • Suarez, M. J., and P. S. Schopf, 1988: A delayed action oscillator for ENSO. J. Atmos. Sci.,45, 3283–3287.

  • Tiedtke, M., 1984: The effect of penetrative cumulus convection on the large scale flow in a general circulation model. Beitr. Phys. Atmos.,57, 216–239.

  • Vernekar, A., B. Kirtman, J. Zhou, and D. DeWitt, 1991: Orographic gravity-wave drag effects on medium-range forecasts with a general circulation model. Physical Processes in Atmospheric Models, D. R. Sikka and S. S. Singh, Eds., Wiley Eastern Limited, 295–307.

  • Xue, Y., P. J. Sellers, J. L. Kinter III, and J. Shukla, 1991: A simplified biosphere model for global climate studies. J. Climate,4, 345–364.

  • Zebiak, S. E., and M. A. Cane, 1987: A model El Nino–Southern Oscillation. Mon. Wea. Rev.,115, 2262–2278.

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