Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 8 1 2008 10.5194/acpd-8-1367-2008 http://www.atmos-chem-phys-discuss.net/8/1367/2008/ http://www.atmos-chem-phys-discuss.net/8/1367/2008/acpd-8-1367-2008.html http://www.atmos-chem-phys-discuss.net/8/1367/2008/acpd-8-1367-2008.pdf 1367 1413 2008-01-29 The Tropical Tropopause Layer 1960–2100 A. Gettelman andrew@ucar.edu T. Birner V. Eyring H. Akiyoshi D. A. Plummer M. Dameris S. Bekki F. Lefèvre F. Lott C. Brühl K. Shibata E. Rozanov E. Mancini G. Pitari H. Struthers W. Tian D. E. Kinnison National Center for Atmospheric Research, Boulder, CO, USA University of Toronto, Toronto, ON, Canada Deutsches Zentrum für Luft- und Raumfahrt, Oberpfaffenhofen, Germany National Institute for Environmental Studies, Tsukuba, Japan Canadian Centre for Climate Modeling and Analysis, Victoria,BC, Canada Université Pierre and Marie Curie, Service d'Aeronomie, Paris, France L'Institut Pierre-Simon Laplace, Ecole Normale Superieur, Paris, France Max Planck Institut für Chemie, Mainz, Germany Meteorological Research Institute, Tsukuba, Japan Physikalisch-Meteorologisches Observatorium Davos, Davos, Switzerland Universita degli Studi de L'Aquila, L'Aquila, Italy National Institute for Water and Atmosphere, New Zealand University of Leeds, Leeds, UK The representation of the Tropical Tropopause Layer in 13 different Chemistry Climate Models designed to represent the stratosphere is analyzed. Simulations for 1960–present and 1980–2100 are analyzed and compared to reanalysis model output. Results indicate that the models are able to reproduce the basic structure of the TTL. There is a large spread in cold point tropopause temperatures that may be linked to variation in TTL ozone values. The models are generally able to reproduce historical trends in tropopause pressure obtained from reanalysis products. Simulated historical trends in cold point tropopause temperatures and in the meridional extent of the TTL are not consistent across models. The pressure of both the tropical tropopause and the level of main convective outflow appear to be decreasing (increasing altitude) in historical runs. Similar trends are seen in the future. Models consistently predict decreasing tropopause and convective outflow pressure, by several hPa/decade. Tropical cold point temperatures increase by 0.2 K/decade. This indicates that tropospheric warming dominates stratospheric cooling at the tropical tropopause. Stratospheric water vapor at 100 hPa increases by up to 0.5–1 ppmv by 2100. This is less than implied directly by the temperature and methane increases, highlighting the correlation of tropopause temperatures with stratospheric water vapor, but also the complex nature of TTL transport. Akiyoshi, H., Sugita, T., Kanzawa, H., and Kawamoto, N.: Ozone perturbations in the Arctic summer lower stratosphere as a reflection of NOx chemistry and planetary scale wave activity, J. Geophys. Res., 109, D03304, \doi10.1029/2003JD003632, 2004. Austin, J.: A three-dimensional coupled chemistry-climate model simulation of past stratospheric trends, J. Atmos. Sci., 59, 218–232, 2002. Austin, J. and Butchart, N.: Coupled chemistry-climate model simulation for the period 1980 to 2020: ozone depletion and the start of ozone recovery, Q. J. R. Meteorol. Soc., 129, 3225–3249, 2003. Austin, J. and Wilson, R J.: Ensemble simulations of the decline and recovery of stratospheric ozone, J. Geophys. Res., 111, D16314, \doi10.1029/2005JD006907, 2006. Austin, J., Wilson, R J., Li, F., and Vömel, H.: Evolution of water vapor concentrations and stratospheric age of air in coupled chemistry-climate model simulations, J. Atmos. Sci., 64, 905–921, 2007. Beagley, S R., de~Grandpré, J., Koshyk, J., McFarlane, N A., and Shepherd, T G.: Radiative–dynamical climatology of the first–generation Canadian Middle Atmosphere Model, Atmos–Ocean, 35, 293–331, 1997. Birner, T., Sankey, D., and Shepherd, T G.: The tropopause inversion layer in models and analyses, Geophys. Res. Lett., 33, L14804, doi:10.1029/2006GL026549, 2006. Bloom, S., da Silva, A., Dee, D., et~al.: Documentation and Validation of the Goddard Earth Observing System (GEOS) Data Assimilation System – Version 4, Tech. Rep. Technical Report Series on Global Modeling and Data Assimilation 104606, NASA, 2005. Bony, S., Colman, R., Kattsov, V. M., et~al.: How Well Do We Understand and Evaluate Climate Change Feedback Processes, J. Climate, 19, 3445–3482, 2006. Butchart, N., Scaife, A A., Bourqui, M., de~Grandpre, J., Hare, S. H E., Kettleborough, J., Langematz, U., Manzini, E., Sassi, F., Shibata, K., Shindell, D., and Sigmond, M.: Simulations of anthropogenic change in the strength of the Brewer-Dobson circulation, Clim. Dynam., 27, 727–741, \doi10.1007/s00382-006-0162-4, 2006. Dameris, M., Grewe, V., Ponater, M., et~al.: Long-term changes and variability in a transient simulation with a chemistry-climate model employing realistic forcings, Atmos. Chem. Phys., 5, 2121–2145, 2005. Dameris, M., Matthes, S., Deckert, R., Grewe, V., and Ponater, M.: Solar cycle effect delays onset of ozone recovery, Geophys. Res. Lett., 33, L03806, doi10.1029/2005GL024741, 2006. de Grandpré, J., Beagley, S R., Fomichev, V I., Griffioen, E., McConnell, J C., Medvedev, A S., and Shepherd, T G.: Ozone climatology using interactive chemistry: results from the Canadian Middle Atmosphere Model, J. Geophys. Res., 105, 26 475–26 491, 2000. Efron, B. and Tibshirani, R J.: An introduction to the Bootstrap, vol 57 of \em Monographs on Statistics and Applied Probability\/, Chapman and Hall, New York, 436 pp., 1993. Egorova, T., Rozanov, E., Zubov, V., Manzini, E., Schmutz, W., and Peter, T.: Chemistry-climate model SOCOL: a validation of the present-day climatology, Atmos. Chem. Phys., 5, 1557–1576, 2005. Eyring, V., Butchart, N., Waugh, D. W., et~al.: Assessment of temperature, trace species, and ozone in chemistry-climate model simulations of the recent past, J. Geophys. Res., 111, D22308, \doi10.1029/2006JD007327, 2006. Eyring, V., Waugh, D. W., Bodeker, G. E., et~al.: Multi-model projections of stratospheric ozone in the 21st century, J. Geophys. Res., 112, D16303, \doi10.1029/2006JD008332, 2007. Forster, P. M. d F. and Shine, K P.: Assessing the climate impact of trends in stratospheric water vapor, Geophys. Res. Lett., 29, 1086, doi:10.1029/2001GL013909, 2002. Fu, Q., Johanson, C M., Wallace, J M., and Reichler, T.: Enhanced Mid-Latitude Tropospheric Warming in Satellite Measurements, Science, 312, 1179, 2006. Garcia, R R., Marsh, D., Kinnison, D., Boville, B A., and Sassi, F.: Simulations of secular trends in the middle atmosphere, 1950–2003, J. Geophys. Res., 112, D09301, doi:10.1029/2006JD007485, 2007. Gettelman, A. and Forster, P. M F.: A Climatology of the Tropical Tropopause Layer, J. Met. Soc. Japan, 80, 911–924, 2002. Gettelman, A. and Kinnison, D E.: The impact of supersaturation in a coupled model, Atmos. Chem. Phys., 6, 1629–1643, 2007. Gettelman, A. and Birner, T.: Insights on Tropical Tropopause Layer Processes using Global Models, J. Geophys. Res., 112, D23104, doi:10.1029/2007JDS008945, 2007. Holton, J R. and Gettelman, A.: Horizontal transport and dehydration in the stratosphere, Geophys. Res. Lett., 28, 2799–2802, 2001. Hu, Y. and Fu, Q.: Observed poleward expansion of the Hadley circulation since 1979, Atmos. Chem. Phys. Discuss., 7, 5229–5236, 2007. IPCC: Special Report on Emission Scenarios, Cambridge University Press, New York, 2000. Johns, T C., Durman, C. F., Banks, H. T., et~al.: The new Hadley Centre climate model Had-GEM1: Evaluation of coupled simulations, J. Climate, 19, 1327–1353, 2006. % %Jourdain, L., Bekki, S., Lott, F., and Lefevre, F.: The coupled chemistry model % LMDz Reprobus: description of a transient simulation of the period % 1980–1999, Ann. Geophys., submitted\blackbox\bf status?, 2008. Kalnay, E., Kanamitsu, M., Kistler, R., Collins, W., Deaven, D., Gandin, L., Iredell, M., Saha, S., White, C., Woollen, J., Zhu, Y., Chelliah, M., Ebisuzaki, W., Higgins, W., Janowiak, J., Mo, K C., Ropelewski, C., Wang, J., Leetmaa, A., Reynolds, R., Jenne, P., and Joseph, D.: The NCEP/NCAR 40-year reanalysis project, B. Am. Meteorol. Soc., 77, 437–471, 1996. Kerr-Munslow, A M. and Norton, W A.: Tropical Wave Driving of the Annual Cycle in Tropical Tropopause Temperatures. Part I: ECMWF Analyses, J. Atmos. Sci., 63, 1410–1419, 2006. Kurokawa, J., Akiyoshi, H., Nagashima, T., Masunaga, H., Nakajima, T., Takahashi, M., and Nakane, H.: Effects of atmospheric sphericity on stratospheric chemistry and dynamics over Antarctica, J. Geophys. Res., 110, D21305, doi:10.1029/2005JD005798, 2005. Lott, F L., Hourdin, F., and Levan, P.: The stratospheric version of LMDz: Dynamical Climatologies, Arctic Oscillation and Impact on the Surface Climate, Clim. Dynam., 25, 851–868, \doi10.1007/s00382-005-0064-x, 2005. Manzini, E., Steil, B., Brühl, C., Giorgetta, M A., and Krüger, K.: A new interactive chemistry climate model. 2: Sensitivity of the middle atmosphere to ozone depletion and increase in greenhouse gases: implications for recent stratospheric cooling,, J. Geophys. Res., 108, 4429, doi:10.1029/2002JD002977, 2003. Pawson, S. and Fiorino, M.: A comparison of reanalyses in the tropical stratosphere, Part 3, Inclusion of the pre-satellite data era, Clim. Dynam., 15, 241–250, 1999. Pitari, G., Mancini, E., Rizzi, V., and Shindell, D.: Impact of future climate and emission changes on stratospheric aerosols and ozone, J. Atmos. Sci., 59, 414–440, 2002. Randel, W J., Wu, F., Vomel, H., Nedoluha, G E., and Forster, P F.: Decreases in stratospheric water vapor since 2001: links to changes in the tropical tropopause and the Brewer-Dobson Circulation, J. Geophys. Res., 111, D12312, \doi10.1029/2005JD006744, 2006. Rozanov, E., Schraner, M., Schnadt, C., Egorova, T., Wild, M., Ohmura, A., Zubov, V., Schmutz, W., and Peter, T.: Assessment of the ozone and temperature variability during 1979–1993 with the chemistry-climate model SOCOL, Adv. Space. Res., 35, 1375–1384, 2005. Santer, B D., Wehner, M F., Wigley, T M L., Sausen, R., Meehl, G A., Taylor, K E., Ammann, C., Arblaster, J., Washington, W M., Boyle, J S., and Brüggemann, W.: Contributions of Anthropogenic and Natural Forcing to Recent Tropopause Height Changes, Science, 301, 479–483, \doi10.1126/science.1084123, 2003. Santer, B D. et~al.: Amplification of Surface Temperature Trends and Variability in the Tropical Atmosphere, Science, 309, 1551–1556, \doi10.1126/science.1114867, 2005. Seidel, D J. and Randel, W J.: Recent Widening of the Tropical Belt: Evidence from Tropopause Observations, in Press, J. Geophys. Res., 2007. Seidel, D J., Ross, R J., Angell, J K., and Reid, G C.: Climatological characteristics of the tropical tropopause as revealed by Radiosondes, J. Geophys. Res., 106, 7857–7878, 2001. Shibata, K. and Deushi, M.: Partitioning between resolved wave forcing and unresolved gravity wave forcing to the quasi-biennial oscillation as revealed with a coupled chemistry-climate model, Geophys. Res. Lett., 32, L12820, \doi10.1029/2005GL022885, 2005. Shibata, K., Deushi, M., Sekiyama, T T., and Yoshimura, H.: Development of an MRI chemical transport model for the study of stratospheric chemistry, Papers in Met. and Geophys., 55, 75–119, 2005. % %Son, S W., Polvani, L M., Waugh, D W., Birner, T., Garcia, R R., Gettelman, % A., and Plummer, D A.: The tropopause in the 21st century as simulated by % stratosphere-resolving Chemistry-Climate Models, J. Climate, submitted, 2008. Steil, B., Brühl, C., Manzini, E., Crutzen, P J., Lelieveld, J., Rasch, P J., Roeckner, E., and Krüger, K.: A new interactive chemistry climate model. 1: Present day climatology and interannual variability of the middle atmosphere using the model and 9 years of HALOE/UARS data, J. Geophys. Res., 108, 4290, \doi10.1029/2002JD002971, 2003. Stephens, G L.: Cloud Feedbacks in the Climate System: A Critical Review, J. Climate, 18, 237–273, 2005. Stolarski, R S., Douglass, A R., Steenrod, S., and Pawson, S.: Trends in Stratospheric Ozone: Lessons Learned from a 3D Chemical Transport Model, J. Atmos. Sci., 63, 1028–1041, 2006. Struthers, H., Kreher, K., Austin, J., Schofield, R., Bodeker, G E., Johnston, P V., Shiona, H., and Thomas, A.: Past and future simulations of NO2 from a coupled chemistry-climate model in comparison with observations, Atmos. Chem. Phys., 4, 2227–2239, 2004. Thuburn, J. and Craig, G C.: On the temperature structure of the tropical substratosphere, J. Geophys. Res., 107, 10.1029/2001JD000448, 2002. Tian, W. and Chipperfield, M P.: A new coupled chemistryÐclimate model for the stratosphere: The importance of coupling for future O3-climate predictions, Q. J. R. Meteorol. Soc., 131, 281–304, 2005. Uppala, S., Kallberg, P., Simmons, A., Andrae, U., da~Costa~Bechtold, V., Fiorino, M., Gibson, J., Haseler, J., Hernandez, A., Kelly, G., Li, X., Onogi, K., Saarinen, S., Sokka, N., Allan, R., Andersson, E., Arpe, K., Balmaseda, M., Beljaars, A., van~de Berg, L., Bidlot, J., Bormann, N., Caires, S., Chevallier, F., Dethof, A., Dragosavac, M., Fisher, M., Fuentes, M., Hagemann, S., Holm, E., Hoskins, B., Isaksen, L., Janssen, P., Jenne, R., McNally, A., Mahfouf, J.-F., Morcrette, J.-J., Rayner, N., Saunders, R., Simon, P., Sterl, A., Trenberth, K., Untch, A., Vasiljevic, D., Viterbo, P., and Woollen, J.: The ERA-40 re-analysis, Q. J. R. Meteorol. Soc., 131, 2961–3012, 2005. World Meteorological Organization: Scientific Assessment of Ozone Depletion: 2002, WMO Report 47, World Meteorological Organization, Geneva, 2003. World Meteorological Organization: Scientific Assessment of Ozone Depletion: 2006, WMO Report 50, World Meteorological Organization, Geneva, 2007. Yin, J H.: A consistent poleward shift of the storm tracks in simulations of 21st century climate, Geophys. Res. Lett., 32, L18701, \doi10.1029/2005GL023684, 2005.