Variations in the Frequency of Stratospheric Sudden Warmings in CMIP5 and CMIP6 and Possible Causes

Zheng Wu Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah

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Thomas Reichler Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah

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Abstract

The climatological frequency of stratospheric sudden warming events (SSWs) is an important dynamical characteristic of the extratropical stratosphere. However, modern climate models have difficulties in simulating this frequency, with many models either considerably under- or overestimating the observational estimates. Past research has found that models with a higher upper lid tend to simulate a higher and more realistic number of SSWs. The present study revisits this issue and investigates causes for biases in the simulated SSW frequency from the CMIP5 and CMIP6 models. It is found that variations in the frequency are closely related to 1) the strength of the polar vortex and 2) the upward-propagating wave activity in the stratosphere. While it is difficult to explain the variations in the polar vortex strength from the available model output, the stratospheric wave activity is influenced by different aspects of the climatological mean state of the atmosphere in the lower stratosphere. We further find that models with a finer vertical resolution in the stratosphere are overall more realistic: vertical resolution is associated with a smaller cold bias above the extratropical tropopause, more upward-propagating wave activity in the lower stratosphere, and a higher frequency of SSWs. We conclude that not only a high model lid but also a fine vertical resolution in the stratosphere is important for simulating the dynamical variability of the stratosphere.

Current affiliation: Institute of Atmospheric and Climate Science IAC ETH, The Swiss Federal Institute of Technology (ETHZ), Zurich, Switzerland.

© 2020 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Zheng Wu, zheng.winnie.wu@utah.edu

Abstract

The climatological frequency of stratospheric sudden warming events (SSWs) is an important dynamical characteristic of the extratropical stratosphere. However, modern climate models have difficulties in simulating this frequency, with many models either considerably under- or overestimating the observational estimates. Past research has found that models with a higher upper lid tend to simulate a higher and more realistic number of SSWs. The present study revisits this issue and investigates causes for biases in the simulated SSW frequency from the CMIP5 and CMIP6 models. It is found that variations in the frequency are closely related to 1) the strength of the polar vortex and 2) the upward-propagating wave activity in the stratosphere. While it is difficult to explain the variations in the polar vortex strength from the available model output, the stratospheric wave activity is influenced by different aspects of the climatological mean state of the atmosphere in the lower stratosphere. We further find that models with a finer vertical resolution in the stratosphere are overall more realistic: vertical resolution is associated with a smaller cold bias above the extratropical tropopause, more upward-propagating wave activity in the lower stratosphere, and a higher frequency of SSWs. We conclude that not only a high model lid but also a fine vertical resolution in the stratosphere is important for simulating the dynamical variability of the stratosphere.

Current affiliation: Institute of Atmospheric and Climate Science IAC ETH, The Swiss Federal Institute of Technology (ETHZ), Zurich, Switzerland.

© 2020 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Zheng Wu, zheng.winnie.wu@utah.edu
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  • Ao, C. O., and Coauthors, 2015: Evaluation of CMIP5 upper troposphere and lower stratosphere geopotential height with GPS radio occultation observations. J. Geophys. Res. Atmos., 120, 16781689, https://doi.org/10.1002/2014JD022239.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ayarzagüena, B., and Coauthors, 2018: No robust evidence of future changes in major stratospheric sudden warmings: A multi-model assessment from CCMI. Atmos. Chem. Phys., 18, 11 27711 287, https://doi.org/10.5194/ACP-18-11277-2018.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ayarzagüena, B., and Coauthors, 2020: Uncertainty in the response of sudden stratospheric warmings and stratosphere–troposphere coupling to quadrupled CO2 concentrations in CMIP6 models. J. Geophys. Res. Atmos., 125, e2019JD032345, https://doi.org/10.1029/2019JD032345.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Birner, T., 2006: Fine-scale structure of the extratropical tropopause region. J. Geophys. Res., 111, D04104, https://doi.org/10.1029/2005JD006301.

  • Birner, T., and J. R. Albers, 2017: Sudden stratospheric warmings and anomalous upward wave activity flux. SOLA, 13A, 812, https://doi.org/10.2151/SOLA.13A-002.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Butchart, N., and Coauthors, 2011: Multimodel climate and variability of the stratosphere. J. Geophys. Res., 116, D05102, https://doi.org/10.1029/2010JD014995.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Butler, A. H., J. P. Sjoberg, D. J. Seidel, and K. H. Rosenlof, 2017: A sudden stratospheric warming compendium. Earth Syst. Sci. Data, 9, 6376, https://doi.org/10.5194/ESSD-9-63-2017.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Butler, A. H., and Coauthors, 2019: Sub-seasonal predictability and the stratosphere. Sub-Seasonal to Seasonal Prediction, A. W. Robertson and F. Vitart, Eds., Elsevier, 223–241.

    • Crossref
    • Export Citation
  • Charlton, A. J., and L. M. Polvani, 2007: A new look at stratospheric sudden warmings. Part I: Climatology and modeling benchmarks. J. Climate, 20, 449469, https://doi.org/10.1175/JCLI3996.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Charlton, A. J., and Coauthors, 2007: A new look at stratospheric sudden warmings. Part II: Evaluation of numerical model simulations. J. Climate, 20, 470488, https://doi.org/10.1175/JCLI3994.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Charlton-Perez, A. J., and Coauthors, 2013: On the lack of stratospheric dynamical variability in low-top versions of the CMIP5 models. J. Geophys. Res. Atmos., 118, 24942505, https://doi.org/10.1002/JGRD.50125.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chen, P., and W. A. Robinson, 1992: Propagation of planetary waves between the troposphere and stratosphere. J. Atmos. Sci., 49, 25332545, https://doi.org/10.1175/1520-0469(1992)049<2533:POPWBT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Dee, D. P., and Coauthors, 2011: The ERA-Interim reanalysis: Configuration and performance of the data assimilation system. Quart. J. Roy. Meteor. Soc., 137, 553597, https://doi.org/10.1002/qj.828.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • de la Cámara, A., J. R. Albers, and T. Birner, 2017: Sensitivity of sudden stratospheric warmings to previous stratospheric conditions. J. Atmos. Sci., 74, 28572877, https://doi.org/10.1175/JAS-D-17-0136.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Draper, N. R., and H. Smith, 1998: Applied Regression Analysis. Wiley-Interscience, 706 pp.

  • Edmon, H. J., B. J. Hoskins, and M. E. McIntyre, 1981: Eliassen–Palm cross sections for the troposphere. J. Atmos. Sci., 37, 26002616, https://doi.org/10.1175/1520-0469(1980)037<2600:epcsft>2.0.co;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Eliassen, A., and E. Palm, 1961: On the transfer of energy in stationary mountain waves. Geofys. Publ., 3, 123.

  • Gerber, E. P., and L. M. Polvani, 2009: Stratosphere–troposphere coupling in a relatively simple AGCM: The importance of stratospheric variability. J. Climate, 22, 19201933, https://doi.org/10.1175/2008JCLI2548.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gerber, E. P., and E. Manzini, 2016: The Dynamics and Variability Model Intercomparison Project (DynVarMIP) for CMIP6: Assessing the stratosphere–troposphere system. Geosci. Model Dev., 9, 34133425, https://doi.org/10.5194/GMD-9-3413-2016.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gettelman, A., L. L. Pan, W. J. Randel, P. Hoor, T. Birner, and M. I. Hegglin, 2011: The extratropical upper troposphere and lower stratosphere. Rev. Geophys., 49, 131, https://doi.org/10.1029/2011RG000355.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hegglin, M. I., and Coauthors, 2010: Multimodel assessment of the upper troposphere and lower stratosphere: Extratropics. J. Geophys. Res., 115, D00M09, https://doi.org/10.1029/2010JD013884.

    • Search Google Scholar
    • Export Citation
  • Horan, M. F., and T. Reichler, 2017: Modeling seasonal sudden stratospheric warming climatology based on polar vortex statistics. J. Climate, 30, 10 10110 116, https://doi.org/10.1175/JCLI-D-17-0257.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jucker, M., 2016: Are sudden stratospheric warmings generic? Insights from an idealized GCM. J. Atmos. Sci., 73, 50615080, https://doi.org/10.1175/JAS-D-15-0353.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jucker, M., S. Fueglistaler, and G. K. Vallis, 2014: Stratospheric sudden warmings in an idealized GCM. J. Geophys. Res. Atmos., 119, 11 05411 064, https://doi.org/10.1002/2014JD022170.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Karoly, D. J., and B. J. Hoskins, 1982: Three-dimensional propagation of planetary waves. J. Meteor. Soc. Japan, 60, 109123, https://doi.org/10.2151/JMSJ1965.60.1_109.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Karpechko, A. Y., P. Hitchcock, H. W. Peters, and A. Schneidereit, 2017: Predictability of downward propagation of major sudden stratospheric warmings. Quart. J. Roy. Meteor. Soc., 143, 14591470, https://doi.org/10.1002/QJ.3017.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kim, J., K. M. Grise, and S. W. Son, 2013: Thermal characteristics of the cold-point tropopause region in CMIP5 models. J. Geophys. Res. Atmos., 118, 88278841, https://doi.org/10.1002/JGRD.50649.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lee, Y., and R. X. Black, 2015: The structure and dynamics of the stratospheric northern annular mode in CMIP5 simulations. J. Climate, 28, 86107, https://doi.org/10.1175/JCLI-D-13-00570.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Martineau, P., G. Chen, S. W. Son, and J. Kim, 2018: Lower-stratospheric control of the frequency of sudden stratospheric warming events. J. Geophys. Res. Atmos., 123, 30513070, https://doi.org/10.1002/2017JD027648.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Matsuno, T., 1970: Vertical propagation of stationary planetary waves in the winter Northern Hemisphere. J. Atmos. Sci., 27, 871883, https://doi.org/10.1175/1520-0469(1970)027<0871:VPOSPW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Polichtchouk, I., T. Stockdale, P. Bechtold, M. Diamantakis, S. Malardel, I. Sandu, F. Vána, and N. Wedi, 2019: Control on stratospheric temperature in IFS: Resolution and vertical advection. ECMWF Tech. Memo. 847, 38 pp., https://www.ecmwf.int/sites/default/files/elibrary/2019/19084-control-stratospheric-temperature-ifs-resolution-and-vertical-advection.pdf.

  • Reichler, T., M. Dameris, and R. Sausen, 2003: Determining the tropopause height from gridded data. Geophys. Res. Lett., 30, 2042, https://doi.org/10.1029/2003GL018240.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Scaife, A. A., T. Woollings, J. Knight, G. Martin, and T. Hinton, 2010: Atmospheric blocking and mean biases in climate models. J. Climate, 23, 61436152, https://doi.org/10.1175/2010JCLI3728.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schimanke, S., T. Spangehl, H. Huebener, and U. Cubasch, 2013: Variability and trends of major stratospheric warmings in simulations under constant and increasing GHG concentrations. Climate Dyn., 40, 17331747, https://doi.org/10.1007/S00382-012-1530-X.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Scott, R. K., and L. M. Polvani, 2004: Stratospheric control of upward wave flux near the tropopause. Geophys. Res. Lett., 31, L02115, https://doi.org/10.1029/2003GL017965.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shaw, T. A., and J. Perlwitz, 2010: The impact of stratospheric model configuration on planetary-scale waves in Northern Hemisphere winter. J. Climate, 23, 33693389, https://doi.org/10.1175/2010JCLI3438.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shaw, T. A., J. Perlwitz, and O. Weiner, 2014: Troposphere–stratosphere coupling: Links to North Atlantic weather and climate, including their representation in CMIP5 models. J. Geophys. Res. Atmos., 119, 58645880, https://doi.org/10.1002/2013JD021191.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sigmond, M., and J. F. Scinocca, 2010: The influence of the basic state on the Northern Hemisphere circulation response to climate change. J. Climate, 23, 14341446, https://doi.org/10.1175/2009JCLI3167.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sigmond, M., J. F. Scinocca, V. V. Kharin, and T. G. Shepherd, 2013: Enhanced seasonal forecast skill following stratospheric sudden warmings. Nat. Geosci., 6, 98102, https://doi.org/10.1038/NGEO1698.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Simpson, I. R., M. Blackburn, and J. D. Haigh, 2009: The role of eddies in driving the tropospheric response to stratospheric heating perturbations. J. Atmos. Sci., 66, 13471365, https://doi.org/10.1175/2008JAS2758.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sjoberg, J. P., and T. Birner, 2014: Stratospheric wave–mean flow feedbacks and sudden stratospheric warmings in a simple model forced by upward wave activity flux. J. Atmos. Sci., 71, 40554071, https://doi.org/10.1175/JAS-D-14-0113.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Son, S. W., S. Lee, and S. B. Feldstein, 2007: Intraseasonal variability of the zonal-mean extratropical tropopause height. J. Atmos. Sci., 64, 608620, https://doi.org/10.1175/JAS3855.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • SPARC, 2010: SPARC CCMVal Report on the Evaluation of Chemistry-Climate Models. SPARC Rep. 5, WCRP-30/2010, WMO/TD-40, www.sparc-climate.org/publications/sparc-reports/.

  • Taguchi, M., 2017: A study of different frequencies of major stratospheric sudden warmings in CMIP5 historical simulations. J. Geophys. Res. Atmos., 122, 51445156, https://doi.org/10.1002/2016JD025826.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Tripathi, O. P., and Coauthors, 2015: The predictability of the extratropical stratosphere on monthly time-scales and its impact on the skill of tropospheric forecasts. Quart. J. Roy. Meteor. Soc., 141, 9871003, https://doi.org/10.1002/qj.2432.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Uppala, S. M., and Coauthors, 2005: The ERA-40 Re-Analysis. Quart. J. Roy. Meteor. Soc., 131, 29613012, https://doi.org/10.1256/qj.04.176.

  • Wang, W., M. Shangguan, W. Tian, T. Schmidt, and A. Ding, 2019: Large uncertainties in estimation of tropical tropopause temperature variabilities due to model vertical resolution. Geophys. Res. Lett., 46, 10 04310 052, https://doi.org/10.1029/2019GL084112.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wu, Z., and T. Reichler, 2019: Surface control of the frequency of stratospheric sudden warming events. J. Climate, 32, 47534766, https://doi.org/10.1175/JCLI-D-18-0801.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
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