• Baran, A. J., , P. Hill, , K. Furtado, , P. Field, , and J. Manners, 2014: A coupled cloud physics–radiation parameterization of the bulk optical properties of cirrus and its impact on the Met Office Unified Model Global Atmosphere 5.0 configuration. J. Climate, 27, 77257752, doi:10.1175/JCLI-D-13-00700.1.

    • Search Google Scholar
    • Export Citation
  • Bodas-Salcedo, A., and et al. , 2011: COSP: Satellite simulation software for model assessment. Bull. Amer. Meteor. Soc., 92, 10231043, doi:10.1175/2011BAMS2856.1.

    • Search Google Scholar
    • Export Citation
  • Bodeker Scientific, 2008: The Binary Data Base of Profiles, tier 1.4, version 1.1.0.6. Bodeker Scientific, accessed 10 February 2014. [Available online at http://www.bodekerscientific.com/data/the-bdbp.]

  • Brown, A., , S. Milton, , M. Cullen, , B. Golding, , J. Mitchell, , and A. Shelly, 2012: Unified modeling and prediction of weather and climate: A 25-year journey. Bull. Amer. Meteor. Soc., 93, 18651877, doi:10.1175/BAMS-D-12-00018.1.

    • Search Google Scholar
    • Export Citation
  • Butchart, N., 2014: The Brewer–Dobson circulation. Rev. Geophys., 52, 157184, doi:10.1002/2013RG000448.

  • Chepfer, H., , S. Bony, , D. Winker, , M. Chiriaco, , J.-L. Dufresne, , and G. Sèze, 2008: Use of CALIPSO lidar observations to evaluate the cloudiness simulated by a climate model. Geophys. Res. Lett., 35, L15704, doi:10.1029/2008GL034207.

    • Search Google Scholar
    • Export Citation
  • Ciais, P., and et al. , 2013: Carbon and other biogeochemical cycles. Climate Change 2013: The Physical Science Basis. T. F. Stocker et al., Eds., Cambridge University Press, 465–570.

    • Search Google Scholar
    • Export Citation
  • Cionni, I., and et al. , 2011: Ozone database in support of CMIP5 simulations: Results and corresponding radiative forcing. Atmos. Chem. Phys., 11, 11 26711 292, doi:10.5194/acp-11-11267-2011.

    • Search Google Scholar
    • Export Citation
  • Collins, M., , S. F. B. Tett, , and C. Cooper, 2001: The internal climate variability of HadCM3, a version of the Hadley Centre coupled model without flux adjustments. Climate Dyn., 17, 6181, doi:10.1007/s003820000094.

    • Search Google Scholar
    • Export Citation
  • Cotton, R. J., and et al. , 2013: The effective density of small ice particles obtained from in situ aircraft observations of mid-latitude cirrus. Quart. J. Roy. Meteor. Soc., 139, 19231934, doi:10.1002/qj.2058.

    • Search Google Scholar
    • Export Citation
  • Cullen, M. J. P., 1993: The Unified Forecast/Climate Model. Meteor. Mag., 122, 8194.

  • Cusack, S., , J. M. Edwards, , and J. M. Crowther, 1999: Investigating k distribution methods for parameterizing gaseous absorption in the Hadley Centre Climate Model. J. Geophys. Res., 104 (D2), 20512057, doi:10.1029/1998JD200063.

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

    • Search Google Scholar
    • Export Citation
  • Derbyshire, S. H., , A. V. Maidens, , S. F. Milton, , R. A. Stratton, , and M. R. Willett, 2011: Adaptive detrainment in a convective parametrization. Quart. J. Roy. Meteor. Soc., 137, 18561871, doi:10.1002/qj.875.

    • Search Google Scholar
    • Export Citation
  • Dessler, A. E., , M. R. Schoeberl, , T. Wang, , S. M. Davis, , K. H. Rosenlof, , and J.-P. Vernier, 2014: Variations of stratospheric water vapor over the past three decades. J. Geophys. Res. Atmos., 119, 12 588–12 598, doi:10.1002/2014JD021712.

    • Search Google Scholar
    • Export Citation
  • Dinh, T., , and S. Fueglistaler, 2014: Microphysical, radiative, and dynamical impacts of thin cirrus clouds on humidity in the tropical tropopause layer and lower stratosphere. Geophys. Res. Lett., 41, 6949–6955, doi:10.1002/2014GL061289.

    • Search Google Scholar
    • Export Citation
  • ECMWF, 2011: ERA-Interim dataset (January 1979 to present). ECMWF Data Server, accessed 20 October 2014. [Available online at http://apps.ecmwf.int/datasets/data/interim-full-moda/?levtype=pl.]

  • Edwards, J. M., , and A. Slingo, 1996: Studies with a flexible new radiation code. I: Choosing a configuration for a large-scale model. Quart. J. Roy. Meteor. Soc., 122, 689719, doi:10.1002/qj.49712253107.

    • Search Google Scholar
    • Export Citation
  • Edwards, J. M., , S. Havemann, , J.-C. Thelen, , and A. J. Baran, 2007: A new parametrization for the radiative properties of ice crystals: Comparison with existing schemes and impact in a GCM. Atmos. Res.,83, 19–35, doi:10.1016/j.atmosres.2006.03.002.

  • Evan, S., , K. H. Rosenlof, , J. Dudhia, , B. Hassler, , and S. M. Davis, 2013: The representation of the TTL in a tropical channel version of the WRF model. J. Geophys. Res. Atmos., 118, 28352848, doi:10.1002/jgrd.50288.

    • Search Google Scholar
    • Export Citation
  • Field, P. R., , A. J. Heymsfield, , and A. Bansemer, 2006: Shattering and particle interarrival times measured by optical array probes in ice clouds. J. Atmos. Oceanic Technol., 23, 13571371, doi:10.1175/JTECH1922.1.

    • Search Google Scholar
    • Export Citation
  • Field, P. R., , A. J. Heymsfield, , and A. Bansemer, 2007: Snow size distribution parameterization for midlatitude and tropical ice clouds. J. Atmos. Sci., 64, 43464365, doi:10.1175/2007JAS2344.1.

    • Search Google Scholar
    • Export Citation
  • Flannaghan, T. J., , and S. Fueglistaler, 2011: Kelvin waves and shear-flow turbulent mixing in the TTL in (re-)analysis data. Geophys. Res. Lett., 38, L02801, doi:10.1029/2010GL045524.

    • Search Google Scholar
    • Export Citation
  • Flannaghan, T. J., , and S. Fueglistaler, 2014: Vertical mixing and the temperature and wind structure of the tropical tropopause layer. J. Atmos. Sci., 71, 16091622, doi:10.1175/JAS-D-13-0321.1.

    • Search Google Scholar
    • Export Citation
  • Flato, G., and et al. , 2013: Evaluation of climate models. Climate Change 2013: The Physical Science Basis, T. F. Stocker et al., Eds., Cambridge University Press, 741–866.

    • Search Google Scholar
    • Export Citation
  • Forster, P. M. de F., , and K. P. Shine, 1999: Stratospheric water vapour changes as a possible contributor to observed stratospheric cooling. Geophys. Res. Lett., 26, 33093312, doi:10.1029/1999GL010487.

    • Search Google Scholar
    • Export Citation
  • Forster, P. M. de F., , and K. P. Shine, 2002: Assessing the climate impact of trends in stratospheric water vapor. Geophys. Res. Lett., 29 (6), doi:10.1029/2001GL013909.

    • Search Google Scholar
    • Export Citation
  • Fueglistaler, S., , and P. H. Haynes, 2005: Control of interannual and longer-term variability of stratospheric water vapor. J. Geophys. Res., 110, D24108, doi:10.1029/2005JD006019.

    • Search Google Scholar
    • Export Citation
  • Fueglistaler, S., , A. E. Dessler, , T. J. Dunkerton, , I. Folkins, , Q. Fu, , and P. W. Mote, 2009: Tropical tropopause layer. Rev. Geophys., 47, RG1004, doi:10.1029/2008RG000267.

    • Search Google Scholar
    • Export Citation
  • Fueglistaler, S., and et al. , 2013: The relation between atmospheric humidity and temperature trends for stratospheric water. J. Geophys. Res. Atmos., 118, 10521074, doi:10.1002/jgrd.50157.

    • Search Google Scholar
    • Export Citation
  • Furtado, K., , P. R. Field, , R. Cotton, , and A. J. Baran, 2015: The sensitivity of simulated high cloud to ice crystal fall speed, shape and size distribution. Quart. J. Roy. Meteor. Soc., doi:10.1002/qj.2457, in press.

    • Search Google Scholar
    • Export Citation
  • Gettelman, A., and et al. , 2010: Multimodel assessment of the upper troposphere and lower stratosphere: Tropics and global trends. J. Geophys. Res., 115, D00M08, doi:10.1029/2009JD013638.

    • Search Google Scholar
    • Export Citation
  • Gettelman, A., , X. Liu, , D. Barahona, , U. Lohmann, , and C. Chen, 2012: Climate impacts of ice nucleation. J. Geophys. Res., 117, D20201, doi:10.1029/2012JD017950.

    • Search Google Scholar
    • Export Citation
  • Global Modeling and Assimilation Office, 2011: Modern-Era Retrospective Analysis for Research and Applications. Goddard Earth Sciences Data and Information Services Center, accessed 15 September 2014. [Available online at http://disc.sci.gsfc.nasa.gov/daac-bin/DataHoldings.pl.]

  • Goff, J. A., 1965: Saturation pressure of water on the new Kelvin scale. Humidity and Moisture: Fundamentals and Standards, A. Wexler and W. A. Wildhack, Eds., 289 pp.

  • Gregory, D., , and P. R. Rowntree, 1990: A mass flux convection scheme with representation of cloud ensemble characteristics and stability-dependent closure. Mon. Wea. Rev., 118, 14831506, doi:10.1175/1520-0493(1990)118<1483:AMFCSW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Gregory, D., , and S. Allen, 1991: The effect of convective scale downdrafts upon NWP and climate simulations. Ninth Conf. on Numerical Weather Prediction. Denver, CO, Amer. Meteor. Soc., 122–123.

  • Haimberger, L., , C. Tavolato, , and S. Sperka, 2012: Homogenization of the global radiosonde temperature dataset through combined comparison with reanalysis background series and neighboring stations. J. Climate, 25, 81088131, doi:10.1175/JCLI-D-11-00668.1.

    • Search Google Scholar
    • Export Citation
  • Haimberger, L., and et al. , 2013: Radiosonde Innovation Composite Homogenization (RICH) dataset, version 1.5. Institut fur Meteorologie and Geophysik, accessed 13 April 2015. [Available online at http://www.univie.ac.at/theoret-met/research/raobcore/.]

  • Hardiman, S. C., , N. Butchart, , S. M. Osprey, , L. J. Gray, , A. C. Bushell, , and T. J. Hinton, 2010: The climatology of the middle atmosphere in a vertically extended version of the Met Office’s climate model. Part I: Mean state. J. Atmos. Sci., 67, 15091525, doi:10.1175/2009JAS3337.1.

    • Search Google Scholar
    • Export Citation
  • Hardiman, S. C., , N. Butchart, , and N. Calvo, 2014: The morphology of the Brewer–Dobson circulation and its response to climate change in CMIP5 simulations. Quart. J. Roy. Meteor. Soc., 140, 19581965, doi:10.1002/qj.2258.

    • Search Google Scholar
    • Export Citation
  • Hassler, B., , G. E. Bodeker, , and M. Dameris, 2008: Technical note: A new global database of trace gases and aerosols from multiple sources of high vertical resolution measurements. Atmos. Chem. Phys., 8, 54035421, doi:10.5194/acp-8-5403-2008.

    • Search Google Scholar
    • Export Citation
  • Hassler, B., , G. E. Bodeker, , I. Cionni, , and M. Dameris, 2009: A vertically resolved, monthly mean, ozone database from 1979 to 2100 for constraining global climate model simulations. Int. J. Remote Sens., 30, 40094018, doi:10.1080/01431160902821874.

    • Search Google Scholar
    • Export Citation
  • Haywood, J., , and O. Boucher, 2000: Estimates of the direct and indirect radiative forcing due to tropospheric aerosols: A review. Rev. Geophys., 38, 513543, doi:10.1029/1999RG000078.

    • Search Google Scholar
    • Export Citation
  • Hegglin, M. I., , and T. G. Shepherd, 2009: Large climate-induced changes in ultraviolet index and stratosphere-to-troposphere ozone flux. Nat. Geosci., 2, 687691, doi:10.1038/ngeo604.

    • Search Google Scholar
    • Export Citation
  • Hegglin, M. I., and et al. , 2013: SPARC data initiative: Comparison of water vapor climatologies from international satellite limb sounders. J. Geophys. Res. Atmos., 118, 11 82411 846, doi:10.1002/jgrd.50752.

    • Search Google Scholar
    • Export Citation
  • Holton, J. R., , and A. Gettelman, 2001: Horizontal transport and the dehydration of the stratosphere. Geophys. Res. Lett., 28, 27992802, doi:10.1029/2001GL013148.

    • Search Google Scholar
    • Export Citation
  • Jensen, E. J., , and L. Pfister, 2004: Transport and freeze-drying in the tropical tropopause layer. J. Geophys. Res., 109, D02207, doi:10.1029/2003JD004022.

    • Search Google Scholar
    • Export Citation
  • Jensen, E. J., , A. S. Ackerman, , and J. A. Smith, 2007: Can overshooting convection dehydrate the tropical tropopause layer? J. Geophys. Res., 112, D11209, doi:10.1029/2006JD007943.

    • Search Google Scholar
    • Export Citation
  • Jones, C. D., and et al. , 2011: The HadGEM2-ES implementation of CMIP5 centennial simulations. Geosci. Model Dev., 4, 543570, doi:10.5194/gmd-4-543-2011.

    • 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, doi:10.1002/jgrd.50649.

    • Search Google Scholar
    • Export Citation
  • Kirk-Davidoff, D. B., , E. J. Hintsa, , J. G. Anderson, , and D. W. Keith, 1999: The effect of climate change on ozone depletion through changes in stratospheric water vapour. Nature, 402, 399401, doi:10.1038/46521.

    • Search Google Scholar
    • Export Citation
  • Korolev, A. V., , and G. A. Isaac, 2005: Shattering during sampling by OAPs and HVPS. Part 1: Snow particles. J. Atmos. Oceanic Technol., 22, 528542, doi:10.1175/JTECH1720.1.

    • Search Google Scholar
    • Export Citation
  • Lacis, A., , D. Wuebbles, , and J. Logan, 1990: Radiative forcing of climate by changes in the vertical distribution of ozone. J. Geophys. Res., 95, 99719981, doi:10.1029/JD095iD07p09971.

    • Search Google Scholar
    • Export Citation
  • Madronich, S., , R. L. McKenzie, , and M. M. Caldwell, 1995: Changes in ultraviolet radiation reaching the earth’s surface. Ambio, 24, 143152.

    • Search Google Scholar
    • Export Citation
  • Martin, G. M., , M. A. Ringer, , V. D. Pope, , A. Jones, , C. Dearden, , and T. J. Hinton, 2006: The physical properties of the atmosphere in the new Hadley Centre Global Environmental Model (HadGEM1). Part I: Model description and global climatology. J. Climate, 19, 12741301, doi:10.1175/JCLI3636.1.

    • Search Google Scholar
    • Export Citation
  • Martin, G. M., and et al. , 2011: The HadGEM2 family of Met Office Unified Model climate configurations. Geosci. Model Dev., 4, 723757, doi:10.5194/gmd-4-723-2011.

    • Search Google Scholar
    • Export Citation
  • Maycock, A. C., , M. M. Joshi, , K. P. Shine, , and A. A. Scaife, 2013: The circulation response to idealized changes in stratospheric water vapor. J. Climate, 26, 545561, doi:10.1175/JCLI-D-12-00155.1.

    • Search Google Scholar
    • Export Citation
  • Maycock, A. C., , M. M. Joshi, , K. P. Shine, , S. M. Davis, , and K. H. Rosenlof, 2014: The potential impact of changes in lower stratospheric water vapour on stratospheric temperatures over the past 30 years. Quart. J. Roy. Meteor. Soc., 140, 21762185, doi:10.1002/qj.2287.

    • Search Google Scholar
    • Export Citation
  • McKenzie, R., , B. Connor, , and G. Bodeker, 1999: Increased summertime UV radiation in New Zealand in response to ozone loss. Science, 285, 17091711, doi:10.1126/science.285.5434.1709.

    • Search Google Scholar
    • Export Citation
  • Morcrette, C. J., 2012: Improvements to a prognostic cloud scheme through changes to its cloud erosion parametrization. Atmos. Sci. Lett., 13, 95102, doi:10.1002/asl.374.

    • Search Google Scholar
    • Export Citation
  • Morgenstern, O., , P. Braesicke, , F. M. O’Connor, , A. C. Bushell, , C. E. Johnson, , S. M. Osprey, , and J. A. Pyle, 2009: Evaluation of the new UKCA climate-composition model—Part 1: The stratosphere. Geosci. Model Dev., 2, 4357, doi:10.5194/gmd-2-43-2009.

    • Search Google Scholar
    • Export Citation
  • Mote, P. W., and et al. , 1996: An atmospheric tape recorder: The imprint of tropical tropopause temperatures on stratospheric water vapor. J. Geophys. Res., 101 (D2), 39894006, doi:10.1029/95JD03422.

    • Search Google Scholar
    • Export Citation
  • NOAA/Earth Systems Research Laboratory, 2014: Stratospheric Water and Ozone Satellite Homogenized dataset, version 02.1. NOAA/Earth System Research Laboratory Chemical Sciences Division, accessed 29 April 2014. [Available online at http://www.esrl.noaa.gov/csd/groups/csd8/swoosh/.]

  • Nowack, P. J., , N. L. Abraham, , A. C. Maycock, , P. Braesicke, , J. M. Gregory, , M. M. Joshi, , A. Osprey, , and J. A. Pyle, 2015: A large ozone-circulation feedback and its implications for global warming assessments. Nat. Climate Change, 5, 41–45, doi:10.1038/nclimate2451.

    • Search Google Scholar
    • Export Citation
  • O’Connor, F. M., and et al. , 2014: Evaluation of the new UKCA climate-composition model—Part 2: The troposphere. Geosci. Model Dev., 7, 4191, doi:10.5194/gmd-7-41-2014.

    • Search Google Scholar
    • Export Citation
  • Orbe, C., , M. Holzer, , and L. M. Polvani, 2012: Flux distributions as robust diagnostics of stratosphere–troposphere exchange. J. Geophys. Res., 117, D01302, doi:10.1029/2011JD016455.

    • Search Google Scholar
    • Export Citation
  • Pope, V. D., , M. L. Gallani, , P. R. Rowntree, , and R. A. Stratton, 2000: The impact of new physical parametrizations in the Hadley Centre climate model—HadAM3. Climate Dyn., 16, 123146, doi:10.1007/s003820050009.

    • Search Google Scholar
    • Export Citation
  • Priestley, A., 1993: A quasi-conservative version of the semi-Lagrangian advection scheme. Mon. Wea. Rev., 121, 621629, doi:10.1175/1520-0493(1993)121<0621:AQCVOT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Rienecker, M. M., and et al. , 2011: MERRA: NASAs Modern-Era Retrospective Analysis for Research and Applications. J. Climate, 24, 36243648, doi:10.1175/JCLI-D-11-00015.1.

    • Search Google Scholar
    • Export Citation
  • Roscoe, H. K., , and J. D. Haigh, 2007: Influences of ozone depletion, the solar cycle and the QBO on the southern annular mode. Quart. J. Roy. Meteor. Soc., 133, 18551864, doi:10.1002/qj.153.

    • Search Google Scholar
    • Export Citation
  • Rosenlof, K. H., and et al. , 2001: Stratospheric water vapor increases over the past half-century. Geophys. Res. Lett., 28, 11951198, doi:10.1029/2000GL012502.

    • Search Google Scholar
    • Export Citation
  • Rothman, L. S., and et al. , 2013: The HITRAN2012 molecular spectroscopic database. J. Quant. Spectrosc. Radiative Transfer, 130, 4–50, doi:10.1016/j.jqsrt.2013.07.002.

  • Russell, J. M., III, and et al. , 1993: The Halogen Occultation Experiment. J. Geophys. Res., 98 (D6), 10 77710 797, doi:10.1029/93JD00799.

    • Search Google Scholar
    • Export Citation
  • Seiki, T., , C. Kodama, , A. T. Noda, , and M. Satoh, 2015: Improvements in global cloud-system resolving simulations by using a double-moment bulk cloud microphysics scheme. J. Climate, 28, 24052419, doi:10.1175/JCLI-D-14-00241.1.

    • Search Google Scholar
    • Export Citation
  • Sherwood, S. C., 2002: A microphysical connection among biomass burning, cumulus clouds, and stratospheric moisture. Science, 295, 12721275, doi:10.1126/science.1065080.

    • Search Google Scholar
    • Export Citation
  • Solomon, S., , R. R. Garcia, , F. S. Rowland, , and D. J. Wuebbles, 1986: On the depletion of Antarctic ozone. Nature, 321, 755758, doi:10.1038/321755a0.

    • Search Google Scholar
    • Export Citation
  • Solomon, S., , K. H. Rosenlof, , R. W. Portmann, , J. S. Daniel, , S. M. Davis, , T. J. Sanford, , and G.-K. Plattner, 2010: Contributions of stratospheric water vapor to decadal changes in the rate of global warming. Science, 327, 12191223, doi:10.1126/science.1182488.

    • Search Google Scholar
    • Export Citation
  • Son, S.-W., and et al. , 2008: The impact of stratospheric ozone recovery on the Southern Hemisphere westerly jet. Science, 320, 14861489, doi:10.1126/science.1155939.

    • Search Google Scholar
    • Export Citation
  • Staniforth, A., , and J. Côté, 1991: Semi-Lagrangian integration schemes for atmospheric models—A review. Mon. Wea. Rev., 119, 22062223, doi:10.1175/1520-0493(1991)119<2206:SLISFA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Stenke, A., , V. Grewe, , and M. Ponater, 2008: Lagrangian transport of water vapor and cloud water in the ECHAM4 GCM and its impact on the cold bias. Climate Dyn., 31, 491506, doi:10.1007/s00382-007-0347-5.

    • Search Google Scholar
    • Export Citation
  • Taylor, K. E., , R. J. Stouffer, , and G. A. Meehl, 2012: An overview of CMIP5 and the experiment design. Bull. Amer. Meteor. Soc., 93, 485498, doi:10.1175/BAMS-D-11-00094.1.

    • Search Google Scholar
    • Export Citation
  • Telford, P. J., and et al. , 2013: Implementation of the Fast-JX Photolysis scheme (v6.4) into the UKCA component of the MetUM chemistry-climate model (v7.3). Geosci. Model Dev., 6, 161177, doi:10.5194/gmd-6-161-2013.

    • Search Google Scholar
    • Export Citation
  • Toon, O. B., , R. P. Turco, , J. Jordan, , J. Goodman, , and G. Ferry, 1989: Physical processes in polar stratospheric ice clouds. J. Geophys. Res., 94, 11 35911 380, doi:10.1029/JD094iD09p11359.

    • Search Google Scholar
    • Export Citation
  • Walters, D. N., and et al. , 2011: The Met Office Unified Model Global Atmosphere 3.0/3.1 and JULES Global Land 3.0/3.1 configurations. Geosci. Model Dev., 4, 919941, doi:10.5194/gmd-4-919-2011.

    • Search Google Scholar
    • Export Citation
  • Walters, D. N., and et al. , 2014: The Met Office Unified Model Global Atmosphere 4.0 and JULES Global Land 4.0 configurations. Geosci. Model Dev., 7, 361386, doi:10.5194/gmd-7-361-2014.

    • Search Google Scholar
    • Export Citation
  • Waters, J. W., and et al. , 2006: The Earth Observing System Microwave Limb Sounder (EOS MLS) on the Aura satellite. IEEE Trans. Geosci. Remote Sens., 44, 10751092, doi:10.1109/TGRS.2006.873771.

    • Search Google Scholar
    • Export Citation
  • Williamson, D. L., 1990: Semi-Lagrangian moisture transport in the NMC spectral model. Tellus, 42A, 413428, doi:10.1034/j.1600-0870.1990.t01-3-00002.x.

    • Search Google Scholar
    • Export Citation
  • Wilson, D. R., , and S. P. Ballard, 1999: A microphysically based precipitation scheme for the UK meteorological office unified model. Quart. J. Roy. Meteor. Soc., 125, 16071636, doi:10.1002/qj.49712555707.

    • Search Google Scholar
    • Export Citation
  • Wilson, D. R., , A. C. Bushell, , A. M. Kerr-Munslow, , J. D. Price, , and C. J. Morcrette, 2008: PC2: A prognostic cloud fraction and condensation scheme. I: Scheme description. Quart. J. Roy. Meteor. Soc., 134, 20932107, doi:10.1002/qj.333.

    • Search Google Scholar
    • Export Citation
  • WMO, 1957: A three-dimensional science: Second session of the commission for aerology. WMO Bull., 6, 134138.

  • Wood, N., and et al. , 2014: An inherently mass-conserving semi-implicit semi-Lagrangian discretization of the deep-atmosphere global non-hydrostatic equations. Quart. J. Roy. Meteor. Soc., 140, 15051520, doi:10.1002/qj.2235.

    • Search Google Scholar
    • Export Citation
  • Zahn, A., , E. Christner, , P. F. J. van Velthoven, , A. Rauthe-Schch, , and C. A. M. Brenninkmeijer, 2014: Processes controlling water vapor in the upper troposphere/lowermost stratosphere: An analysis of 8 years of monthly measurements by the IAGOS-CARIBIC observatory. J. Geophys. Res. Atmos., 119, 11 50511 525, doi:10.1002/2014JD021687.

    • Search Google Scholar
    • Export Citation
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Processes Controlling Tropical Tropopause Temperature and Stratospheric Water Vapor in Climate Models

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  • 1 * Met Office, Exeter, Devon, United Kingdom
  • | 2 Centre for Atmospheric Science, Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
  • | 3 National Centre for Atmospheric Science, Cambridge, United Kingdom
  • | 4 College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom
  • | 5 Commonwealth Scientific and Industrial Research Organisation, Aspendale, Victoria, Australia
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Abstract

A warm bias in tropical tropopause temperature is found in the Met Office Unified Model (MetUM), in common with most models from phase 5 of CMIP (CMIP5). Key dynamical, microphysical, and radiative processes influencing the tropical tropopause temperature and lower-stratospheric water vapor concentrations in climate models are investigated using the MetUM. A series of sensitivity experiments are run to separate the effects of vertical advection, ice optical and microphysical properties, convection, cirrus clouds, and atmospheric composition on simulated tropopause temperature and lower-stratospheric water vapor concentrations in the tropics. The numerical accuracy of the vertical advection, determined in the MetUM by the choice of interpolation and conservation schemes used, is found to be particularly important. Microphysical and radiative processes are found to influence stratospheric water vapor both through modifying the tropical tropopause temperature and through modifying upper-tropospheric water vapor concentrations, allowing more water vapor to be advected into the stratosphere. The representation of any of the processes discussed can act to significantly reduce biases in tropical tropopause temperature and stratospheric water vapor in a physical way, thereby improving climate simulations.

Corresponding author address: Steven C. Hardiman, Met Office Hadley Centre, FitzRoy Road, Exeter, Devon, EX1 3PB, United Kingdom. E-mail: steven.hardiman@metoffice.gov.uk

Abstract

A warm bias in tropical tropopause temperature is found in the Met Office Unified Model (MetUM), in common with most models from phase 5 of CMIP (CMIP5). Key dynamical, microphysical, and radiative processes influencing the tropical tropopause temperature and lower-stratospheric water vapor concentrations in climate models are investigated using the MetUM. A series of sensitivity experiments are run to separate the effects of vertical advection, ice optical and microphysical properties, convection, cirrus clouds, and atmospheric composition on simulated tropopause temperature and lower-stratospheric water vapor concentrations in the tropics. The numerical accuracy of the vertical advection, determined in the MetUM by the choice of interpolation and conservation schemes used, is found to be particularly important. Microphysical and radiative processes are found to influence stratospheric water vapor both through modifying the tropical tropopause temperature and through modifying upper-tropospheric water vapor concentrations, allowing more water vapor to be advected into the stratosphere. The representation of any of the processes discussed can act to significantly reduce biases in tropical tropopause temperature and stratospheric water vapor in a physical way, thereby improving climate simulations.

Corresponding author address: Steven C. Hardiman, Met Office Hadley Centre, FitzRoy Road, Exeter, Devon, EX1 3PB, United Kingdom. E-mail: steven.hardiman@metoffice.gov.uk
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