Editorial Type:
Article
Article Type:
Research Article

The Importance of Atmospheric Dynamics in the Northern Hemisphere Wintertime Climate Response to Changes in the Earth’s Orbit

Alex Hall Department of Atmospheric Sciences, University of California, Los Angeles, Los Angeles, California

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Amy Clement Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida

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David W. J. Thompson Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado

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Anthony Broccoli Department of Environmental Sciences, Rutgers–The State University of New Jersey, New Brunswick, New Jersey

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Charles Jackson Institute for Geophysics, The John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, Austin, Texas

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Print Publication:
01 May 2005
DOI:
https://doi.org/10.1175/JCLI3327.1
Page(s):
1315–1325
Restricted access

Abstract

Milankovitch proposed that variations in the earth’s orbit cause climate variability through a local thermodynamic response to changes in insolation. This hypothesis is tested by examining variability in an atmospheric general circulation model coupled to an ocean mixed layer model subjected to the orbital forcing of the past 165 000 yr. During Northern Hemisphere summer, the model’s response conforms to Milankovitch’s hypothesis, with high (low) insolation generating warm (cold) temperatures throughout the hemisphere. However, during Northern Hemisphere winter, the climate variations stemming from orbital forcing cannot be solely understood as a local thermodynamic response to radiation anomalies. Instead, orbital forcing perturbs the atmospheric circulation in a pattern bearing a striking resemblance to the northern annular mode, the primary mode of simulated and observed unforced atmospheric variability. The hypothesized reason for this similarity is that the circulation response to orbital forcing reflects the same dynamics generating unforced variability. These circulation anomalies are in turn responsible for significant fluctuations in other climate variables: Most of the simulated orbital signatures in wintertime surface air temperature over midlatitude continents are directly traceable not to local radiative forcing, but to orbital excitation of the northern annular mode. This has paleoclimate implications: during the point of the model integration corresponding to the last interglacial (Eemian) period, the orbital excitation of this mode generates a 1°–2°C warm surface air temperature anomaly over Europe, providing an explanation for the warm anomaly of comparable magnitude implied by the paleoclimate proxy record. The results imply that interpretations of the paleoclimate record must account for changes in surface temperature driven not only by changes in insolation, but also by perturbations in atmospheric dynamics.

Corresponding author address: Alex Hall, Dept. of Atmospheric Sciences, University of California, Los Angeles, Los Angeles, CA 90095. Email: alexhall@atmos.ucla.edu

Abstract

Milankovitch proposed that variations in the earth’s orbit cause climate variability through a local thermodynamic response to changes in insolation. This hypothesis is tested by examining variability in an atmospheric general circulation model coupled to an ocean mixed layer model subjected to the orbital forcing of the past 165 000 yr. During Northern Hemisphere summer, the model’s response conforms to Milankovitch’s hypothesis, with high (low) insolation generating warm (cold) temperatures throughout the hemisphere. However, during Northern Hemisphere winter, the climate variations stemming from orbital forcing cannot be solely understood as a local thermodynamic response to radiation anomalies. Instead, orbital forcing perturbs the atmospheric circulation in a pattern bearing a striking resemblance to the northern annular mode, the primary mode of simulated and observed unforced atmospheric variability. The hypothesized reason for this similarity is that the circulation response to orbital forcing reflects the same dynamics generating unforced variability. These circulation anomalies are in turn responsible for significant fluctuations in other climate variables: Most of the simulated orbital signatures in wintertime surface air temperature over midlatitude continents are directly traceable not to local radiative forcing, but to orbital excitation of the northern annular mode. This has paleoclimate implications: during the point of the model integration corresponding to the last interglacial (Eemian) period, the orbital excitation of this mode generates a 1°–2°C warm surface air temperature anomaly over Europe, providing an explanation for the warm anomaly of comparable magnitude implied by the paleoclimate proxy record. The results imply that interpretations of the paleoclimate record must account for changes in surface temperature driven not only by changes in insolation, but also by perturbations in atmospheric dynamics.

Corresponding author address: Alex Hall, Dept. of Atmospheric Sciences, University of California, Los Angeles, Los Angeles, CA 90095. Email: alexhall@atmos.ucla.edu

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  • Aalbersberg, G., and T. Litt, 1998: Multiproxy climate reconstructions for the Eemian and early Weichselian. J. Quat. Sci., 13 , 367–390.

    • Search Google Scholar
    • Export Citation

  • Berger, A., 1992: Orbital variations and insolation database. NOAA/NGDC contribution 92-007, NOAA/NGDC, Boulder, CO. [Available online at http://gcmd.nasa.gov/records/GCMD_EARTH_LAND_NGDC_PALEOCLIM_INSOL.html.].

  • Clement, A. C., R. Seager, and M. A. Cane, 1999: Orbital controls on the El Niño/Southern Oscillation and the tropical climate. Paleoceanography, 14 , 441–456.

    • Search Google Scholar
    • Export Citation

  • Felis, T., G. Lohmann, H. Kuhnert, S. J. Lorenz, D. Scholz, J. Pätzold, S. A. Al-Rousan, and S. M. Al-Moghrabi, 2004: Increased seasonality in Middle East temperatures during the last interglacial period. Nature, 429 , 164–168.

    • Search Google Scholar
    • Export Citation

  • Fyfe, J. C., G. J. Boer, and G. M. Flato, 1999: The Arctic and Antarctic Oscillations and their projected changes under global warming. Geophys. Res. Lett., 26 , 1601–1604.

    • Search Google Scholar
    • Export Citation

  • Gillett, N. P., M. R. Allen, R. E. McDonald, C. A. Senior, D. T. Shindell, and G. A. Schmidt, 2002: How linear is the Arctic Oscillation response to greenhouse gases? J. Geophys. Res., 107 .4022, doi:10.1029/2001JD000589.

    • Search Google Scholar
    • Export Citation

  • Hartmann, D. L., and F. Lo, 1998: Wave-driven zonal flow vacillation in the Southern Hemisphere. J. Atmos. Sci., 55 , 1303–1315.

  • Hays, J. D., J. Imbrie, and N. J. Shackleton, 1976: Variations in the Earth’s orbit: Pacemaker of the Ice Ages. Science, 194 , 1121–1132.

    • Search Google Scholar
    • Export Citation

  • Hurrell, J. W., 1995: Decadal trends in the North Atlantic Oscillation: Regional temperatures and precipitation. Science, 269 , 676–679.

    • Search Google Scholar
    • Export Citation

  • Hurrell, J. W., Y. Kushnir, M. Visbeck, and G. Ottersen, 2003: An overview of the North Atlantic Oscillation. The North Atlantic Oscillation: Climate Significance and Environmental Impact, Geophys. Monogr., Vol. 134, Amer. Geophys. Union, 1–35.

    • Search Google Scholar
    • Export Citation

  • Imbrie, J., and Coauthors, 1984: The orbital theory of Pleistocene climate: Support from a revised chronology of the marine d18O record. Milankovitch and Climate, Part 1, A.L. Berger et al., Eds., D. Riedel, 269–305.

    • Search Google Scholar
    • Export Citation

  • Jackson, C., and A. J. Broccoli, 2003: Orbital forcing of Arctic climate: Mechanisms of climate response and implications for continental glaciation. Climate Dyn., 21 , 539–557.

    • Search Google Scholar
    • Export Citation

  • Karoly, D. J., 1990: The role of transient eddies in low-frequency zonal variations of the Southern Hemisphere circulation. Tellus, 42A , 41–50.

    • Search Google Scholar
    • Export Citation

  • Kidson, J. W., 1988: Indices of the Southern Hemisphere zonal wind. J. Climate, 1 , 183–194.

  • Klotz, S., J. Guiot, and V. Mosbrugger, 2003: Continental European Eemian and early Wurmian climate evolution: Comparing signals using different quantitative reconstruction approaches based on pollen. Global Planet. Change, 36 , 277–294.

    • Search Google Scholar
    • Export Citation

  • Kushnir, Y., W. A. Robinson, I. Blade, N. M. J. Hall, S. Peng, and R. Sutton, 2002: Atmospheric GCM response to extratropical SST anomalies: Synthesis and evaluation. J. Climate, 15 , 2233–2256.

    • Search Google Scholar
    • Export Citation

  • Limpasuvan, V., and D. L. Hartmann, 2000: Wave-maintained annular modes of climate variability. J. Climate, 13 , 4414–4429.

  • Lorenz, D. J., and D. L. Hartmann, 2003: Eddy-zonal flow feedback in the Northern Hemisphere winter. J. Climate, 16 , 1212–1227.

  • Philander, G. S., 1990: El Niño, La Niña, and the Southern Oscillation. Academic Press, 293 pp.

  • Robinson, W. A., 2000: A baroclinic mechanism for the eddy feedback on the zonal index. J. Atmos. Sci., 57 , 415–422.

  • Robock, A., and J. Mao, 1995: The volcanic signal in surface temperature observations. J. Climate, 8 , 1086–1103.

  • Shindell, D. T., R. L. Miller, G. A. Schmidt, and L. Pandolfo, 1999: Simulation of recent northern winter climate trends by greenhouse-gas forcing. Nature, 399 , 452–455.

    • Search Google Scholar
    • Export Citation

  • Shindell, D. T., G. A. Schmidt, M. E. Mann, D. Rind, and A. Waple, 2001: Solar forcing of regional climate change during the Maunder Minimum. Science, 294 , 2149–2152.

    • Search Google Scholar
    • Export Citation

  • Shindell, D. T., G. A. Schmidt, M. E. Mann, and G. Faluvegi, 2004: Dynamic winter climate response to large tropical volcanic eruptions since 1600. J. Geophys. Res., 109 .D05104, doi:10.1029/2003JD004151.

    • Search Google Scholar
    • Export Citation

  • Stenchikov, G., A. Robock, V. Ramaswamy, M. D. Schwarzkopf, K. Hamilton, and S. Ramachandran, 2002: Arctic Oscillation response to the 1991 Mount Pinatubo eruption: Effects of volcanic aerosols and ozone depletion. J. Geophys. Res., 107 .4803, doi:10.1029/2002JD002090.

    • Search Google Scholar
    • Export Citation

  • Thompson, D. W. J., and J. M. Wallace, 2000: Annular modes in the extratropical circulation. Part I: Month-to-month variability. J. Climate, 13 , 1000–1016.

    • Search Google Scholar
    • Export Citation

  • Zagwijn, W. H., 1996: An analysis of Eemian climate in western and central Europe. Quat. Sci. Rev., 15 , 451–469.

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