Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 9 24 2009 10.5194/acp-9-9647-2009 http://www.atmos-chem-phys.net/9/9647/2009/ http://www.atmos-chem-phys.net/9/9647/2009/acp-9-9647-2009.html http://www.atmos-chem-phys.net/9/9647/2009/acp-9-9647-2009.pdf 9647 9660 2009-12-23 Hydration and dehydration at the tropical tropopause C. Schiller c.schiller@fz-juelich.de J.-U. Grooß P. Konopka F. Plöger F. H. Silva dos Santos N. Spelten Forschungzentrum Jülich GmbH, ICG-1, 52425 Jülich, Germany High-resolution water measurements from three tropical airborne missions in Northern Australia, Southern Brazil and West Africa in different seasons are analysed to study the transport and transformation of water in the tropical tropopause layer (TTL) and its impact on the stratosphere. The mean profiles are quite different according to the season and location of the campaigns, with lowest mixing ratios below 2 ppmv at the cold point tropopause during the Australian mission in November/December and high TTL mixing ratios during the African measurements in August. We present backward trajectory calculations considering freeze-drying of the air to the minimum saturation mixing ratio and initialised with climatological satellite data. This trajectory-based reconstruction of water agrees well with the observed H₂O average profiles and therefore demonstrates that the water vapour set point in the TTL is primarily determined by the Lagrangian saturation history. Deep convection was found to moisten the TTL, in several events even above the cold point up to 420 K potential temperatures. However, our study does not provide evidence for a larger impact of these highly-localised events on global scales. Brunner, D., Siegmund, P., May, P. T., Chappel, L., Schiller, C., Müller, R., Peter, T., Fueglistaler, S., MacKenzie, A. R., Fix, A., Schlager, H., Allen, G., Fjaeraa, A. M., Streibel, M., and Harris, N. R. P.: The SCOUT-O3 Darwin Aircraft Campaign: rationale and meteorology, Atmos. Chem. Phys., 9, 93–117, 2009. Brunner, D. and Schiller, C.: Large fluctuations of tropopause moisture over the Maritime Continent induced by a Kelvin wave during the SCOUT-O3 campaign in Darwin, Australia, Atmos. Chem. Phys. Discuss., in preparation, 2009. Cairo, F., Pommereau, J. P., Law, K. S., Schlager, H., Garnier, A., Fierli, F., Ern, M., Streibel, M., Arabas, S., Borrmann, S., Berthelier, J. J., Blom, C., Christensen, T., D'Amato, F., Di Donfrancesco, G., Deshler, T., Diedhiou, A., Durry, G., Engelsen, O., Goutail, F., Harris, N. R. P., Kerstel, E. R. T., Khaykin, S., Konopka, P., Kylling, A., Larsen, N., Lebel, T., Liu, X., MacKenzie, A. R., Nielsen, J., Oulanowski, A., Parker, D. J., Pelon, J., Polcher, J., Pyle, J. A., Ravegnani, F., Rivière, E. D., Robinson, A. D., Röckmann, T., Schiller, C., Simões, F., Stefanutti, L., Stroh, F., Some, L., Siegmund, P., Sitnikov, N., Vernier, J. P., Volk, C. M., Voigt, C., von Hobe, M., Viciani, S., and Yushkov, V.: An overview of the SCOUT-AMMA stratospheric aircraft, balloons and sondes campaign in West Africa, August 2006: rationale, roadmap and highlights, Atmos. Chem. Phys. Discuss., 9, 19713–19781, 2009. Chaboureau, J.-P., Cammas, J.-P., Duron, J., Mascart, P. J., Sitnikov, N. M., and Voessing, H.-J.: A numerical study of tropical cross-tropopause transport by convective overshoots, Atmos. Chem. Phys., 7, 1731–1740, 2007. Chemel, C., Russo, M. R., Pyle, J. A., Sokhi, R. J., and Schiller, C.: Quantifying the imprint of a severe Hector thunderstorm during ACTIVE/SCOUT-O3 onto the water content in the upper troposphere/lower stratosphere, 137, 2493–2514, doi:101175/2008MWR2666.1, 2009. Corti, T., Luo, B. P., Peter, T., Vömel, H., and Fu, Q.: Mean radiative energy balance and vertical mass fluxes in the equatorial upper troposphere and lower stratosphere, Geophys. Res. Lett., 32, L06802, doi:10.1029/2004GL021889, 2005. Corti, T., Luo, B. P., deReus, M., Brunner, D., Cairo, F., Mahoney, M. J., Matucci, G., Matthey, R., Mitev, V., dos Santos, F. H., Schiller, C., Shur, G., Sitnikov, N. M., Spelten, N., Vössing, H. J., Borrmann, S., and Peter, T.: Unprecedented evidence for overshooting convection hydrating the tropical stratosphere, Geophys. Res. Lett., 35, L10810, doi:10.1029/2008GL033641, 2008. Danielsen, E. F.: In situ evidence of rapid, vertical, irreversible transport of lower tropospheric air into the lower tropical stratosphere by convective cloud turrets and by larger-scale upwelling in tropical cyclones, J. Geophys. Res., 98, 8665–8681, 1993. de Reus, M., Borrmann, S., Bansemer, A., Heymsfield, A. J., Weigel, R., Schiller, C., Mitev, V., Frey, W., Kunkel, D., Kürten, A., Curtius, J., Sitnikov, N. M., Ulanovsky, A., and Ravegnani, F.: Evidence for ice particles in the tropical stratosphere from in-situ measurements, Atmos. Chem. Phys., 9, 6775–6792, 2009. Dethof, A.: Aspects of modelling and assimilation for the stratosphere at ECMWF, available via: www.atmosp.physics.utoronto.ca/SPARC/News21/21_Dethof.html, SPARC newsletter 21, 2003. Fueglistaler, S., Bonazzola, M., Haynes, P. H., and Peter, T.: Stratospheric water vapour predicted from the Lagrangian temperature history of air entering the stratosphere in the tropics, J. Geophys. Res., 110, D08017, doi:10.1029/2004JD005516, 2005. Fueglistaler, S. and Haynes, P. H.: Control of interannual and longer-term variability of stratospheric water vapor, J. Geophys. Res., 110, D24108, doi:10.1029/2006JD007273, 2005. Fueglistaler, S., Dessler, A. E., Dunkerton, T. J., Folkins, I., Fu, Q., and Mote, P. W.: Tropical tropopause layer, Rev. Geophys., 47, RG1004, doi:10.1029/2008RG000267, 2009. Gettelman, A., Salby, M. L., and Sassi, F.: Distribution and influence of convection in the tropical tropopause region, J. Geophys. Res., 107(D10), 4080, doi:10.1029/2001JD001048, 2002. Grooß, J.-U. and Russell III, J M.: Technical note: A stratospheric climatology for O₃, H₂O, CH₄, NO$_x$, HCl and HF derived from HALOE measurements, Atmos. Chem. Phys., 5, 2797–2807, 2005. Grosvenor, D. P., Choularton, T. W., Coe, H., and Held, G.: A study of the effect of overshooting deep convection on the water content of the TTL and lower stratosphere from Cloud Resolving Model simulations, Atmos. Chem. Phys., 7, 4977–5002, 2007. Holton, J. R. and Gettelman, A.: Horizontal transport and the dehydration of the stratosphere, Geophys. Res. Lett., 28, 2799–2802, 2001. James, R., Bonazzola, M., Legras, B., Surbled, K., and Fueglistaler, S.: Water vapor transport and dehydration above convective outflow during Asian monsoon, Geophys. Res. Lett., 35, L20810, doi:10.1029/2008GL035441, 2008. Jensen, E. J., Pfister, L., Ackerman, A. S., Tabazadeh, A., and Toon, O. B.: A conceptual model of the dehydration of air due to freeze-drying by optically thin, laminar cirrus rising slowly across the tropical tropopause, J. Geophys. Res., 106, 17237–17252, 2001. Jensen, E. and Pfister, L.: Transport and freeze-drying in the tropical tropopause layer, J. Geophys. Res., 109, D02207, doi:10.1029/2003JD004022, 2004. Jensen, E. J., Ackerman, A. S., and Smith, J. A.: Can overshooting convection dehydrate the tropical tropopause layer?, J. Geophys. Res., 112, D11209, doi:10.1029/2006JD007943, 2007. Jones, A., Urban, J., Murtagh, D. P., Eriksson, P., Brohede, S., Haley, C., Degenstein, D., Bourassa, A., von Savigny, C., Sonkaew, T., Rozanov, A., Bovensmann, H., and Burrows, J.: \mboxEvolution of stratospheric ozone and water vapour time series studied with satellite measurements, Atmos. Chem. Phys., 9, 6055–6075, 2009. Kelly, K. K., Proffitt, M. H., Chan, K. R., Loewenstein, M., Podolske, J. R., Strahan, S. E., Wilson, J. C., and Kley, D.: Water vapour and cloud water measurements over Darwin during the STEP 1987 tropical mission, J. Geophys. Res., 98, 8713–8723, 1993. Khaykin, S., Pommereau, J.-P., Korshunov, L., Yushkov, V., Nielsen, J., Larsen, N., Christensen, T., Garnier, A., Lukyanov, A., and Williams, E.: Hydration of the lower stratosphere by ice crystal geysers over land convective systems, Atmos. Chem. Phys., 9, 2275–2287, 2009. Kley, D., Schmeltekopf, A. L., Kelly, K., Winkler, R. H., Thomson, T. L., and MacFarland, M.: Transport of water through the tropical tropopause, Geophys. Res. Lett., 9, 617–620, 1982. Kley, D., Russell III, J., Phillips, C., edited by: Gettelman, A., Harries, J., Mote, P., Oltmans, S., Remsberg, E., Rosenlof, K., and Schiller, C.: SPARC Assessment of Water Vapour in the Stratosphere and Upper Troposphere, WCRP-113, WMO/TD No. 1043, SPARC Report No. 2, 2000. Konopka, P., Günther, G., Müller, R., dos Santos, F. H. S., Schiller, C., Ravegnani, F., Ulanovsky, A., Schlager, H., Volk, C. M., Viciani, S., Pan, L. L., McKenna, D.-S., and Riese, M.: Contribution of mixing to upward transport across the tropical tropopause layer (TTL), Atmos. Chem. Phys., 7, 3285–3308, 2007. Koop, T., Luo, B. P., Tsias, A., and Peter, T.: Water activity as the determinant for homogeneous ice nucleation in aqueous solutions, Nature, 406, 611–614, 2000. Krämer, M., Schiller, C., Afchine, A., Bauer, R., Gensch, I., Mangold, A., Schlicht, S., Spelten, N., Sitnikov, N., Borrmann, S., de Reus, M., and Spichtinger, P.: Ice supersaturations and cirrus cloud crystal numbers, Atmos. Chem. Phys., 9, 3505–3522, 2009. Lelieveld, J., Brühl, C., Jöckel, P., Steil, B., Crutzen, P. J., Fischer, H., Giorgetta, M. A., Hoor, P., Lawrence, M. G., Sausen, R., and Tost, H.: Stratospheric dryness: model simulations and satellite observations, Atmos. Chem. Phys., 7, 1313–1332, 2007. Liu, C. L. and Zipser, E. J.: Global distribution of convection penetrating the tropical tropopause, J. Geophys. Res., 110, D23104, doi:10.1029/2005JD006063, 2005. MacKenzie, A. R., Schiller, C., Adriani, A., Beuermann, J., Cairo, F., Corti, T., Gensch, I., Krämer, M., Kröger, C., Lepouchov, B., Lowe, D., Merkulov, S., Mitev, V., Oulanovsky, A., Peter, Th., Ravegnani, F., Rohs, S., Rudakov, V., Salter, P., Stefanutti, L., and Yushkov, V.: The tropopause and hygropause in the equatorial Indian Ocean during February and March~1999, J. Geophys. Res., 111(D18), D18112, doi:10.1029/2005JD006639, 2006. May, P. T., Allen, G., Vaughan, G., and Connolly, P.: Aerosol and thermodynamic effects on tropical cloud systems during TWPICE and ACTIVE, Atmos. Chem. Phys., 9, 15–24, 2009. Mote, P. W., Rosenlof, K. H., McIntyre, M. E., Carr, E. S., Gille, J. C., Holton, J. R., Kinnersley, J. S., Pumphrey, H. G., Russell III, J. M., and Watery, J. W.: An atmospheric tape recorder: The imprint of tropical tropopause temperatures on stratospheric water vapour, J. Geophys. Res., 101, 3989–4006, 1996. Newell, R. E. and Gould-Stewart, S.: A stratospheric fountain, J. Atmos. Sci., 38, 2789–2796, 1981. Peter, Th., Luo, B. P., Wirth, M., Kiemle, C., Flentje, H., Yushkov, V. A., Khattatov, V., Rudakov, V., Thomas, A., Borrmann, S., Toci, G., Mazzinghi, P., Beuermann, J., Schiller, C., Cairo, F., Di Donfrancesco, G., Adriani, A., Volk, C. M., Strom, J., Noone, K., Mitev, V., MacKenzie, R. A., Carslaw, K. S., Trautmann, T., Santacesaria, V., and Stefanutti, L.: Ultrathin Tropical Tropopause Clouds (UTTCs): I. Cloud morphology and occurrence, Atmos. Chem. Phys., 3, 1083–1091, 2003. Plöger, F., Konopka, P., Günther, G., Grooß, J.-U., and Müller, R.: Impact of the vertical velocity scheme on modeling transport in the tropical tropopause layer (TTL), J. Geophys. Res., doi:10.1029/2009JD012023, in press, 2009. Randel, W. J., Wu, F., Oltmans, S., Rosenlof, K., and Nedoluha, G. E.: Interannual changes of stratospheric water vapor and correlations with tropical tropopause temperatures, J. Atmos. Sci., 61, 2133–2148, 2004a. Randel, W., Uedelhofen, P., Fleming, E., Gelma, M., Hamilton, K., Karoly, D., Ortland, D., Swinbank, R., Chanin, M.-L., Keckhut, P., Labitzke, K., Remsberg, E., Simmons, A., Wu, D., Geller, M., Pawson, S., Wu, F., and Baldwin, M.: The SPARC intercomparison of middle-atmosphere climatologies, J. Climate, 17, 986–1003, doi:10.1175/1520-0442(2004)017<0986:TSIOMC>2.0.CO;2, 2004b. Randel, W. J., Wu, F., Vömel, H., Nedoluha, G. E., and Forster, P.: Decreases in stratospheric water vapor since 2001: links to changes in the tropical tropopause and the Brewer-Dobson circulation, J. Geophys. Res., 111, D12312, doi:10.1029/2005JD006744, 2006. Randel, W. J. and Park, M.: Deep convective influence on the Asian monsoon anticyclone and associated tracer variability observed with Atmospheric Infrared Sounder (AIRS), J. Geophys. Res., 111, D12314, doi:10.1029/2005JD006490, 2006. Randel, W. J., Park, M., Wu, F., and Livesey, N.: A large annual cycle in ozone above the tropical tropopause linked to the Brewer-Dobson circulation, J. Atmos. Sci., 64 (12), 4479–4488, 2007. Schiller, C., Krämer, M., Afchine, A., Spelten, N., and Sitnikov, N.: The ice water content of Arctic, mid latitude and tropical cirrus, J. Geophys. Res., 113, D24208, doi:10.1029/2008JD010342, 2008. Sherwood, S. C. and Dessler, A. E.: On the control of stratospheric humidity, Geophys. Res. Lett., 27, 2513–2516, 2000. Simmons, A. J., Untch, A., Jakob, C., Kallberg, P., and Unden, P.: Stratospheric water vapour and tropical tropopause temperatures in ECMWF analyes and multi-year simulations, Quart. J. Roy. Met. Soc., 125, 353–386, 1999. Vaughan, G., Schiller, C., MacKenzie, A. R., Bower, K., Peter, T., Schlager, H., Harris, N. R. P., and May, P. T.: SCOUT-O3 /ACTIVE: High-altitude aircraft measurements around deep tropical convection, B. Am. Meteorol. Soc., 89, 647–662, doi:10.1175/BAMS-89-5-647, 2008. Vömel, H., Barnes, J. E., Forno, R. N., Fujiwara, M., Hasebe, F., Iwasaki, S., Kivi, R., Komala, N., Kyrö, E., Leblanc, T., Morel, B., Ogino, S.-Y., Read, W. G., Ryan, S. C., Saraspriya, S., Selkirk, H., Shiotani, M., Valverde Canossa, J., and Whiteman, D. N.: Validation of Aura Microwave Limb Sounder water vapor by balloonborne Cryogenic Frost point Hygrometer measurements, J. Geophys. Res., 112, D24S37, doi:10.1029/2007JD008698, 2007. Zöger, M., Afchine, A., Eicke, N., Gerhards, M.-T., Klein, E., McKenna, D. S., Mörschel, U., Schmidt, U., Tan, V., Tuitjer, F., Woyke, T., and Schiller, C.: Fast in situ stratospheric hygrometers: A new family of balloonborne and airborne Lyman α photofragment fluorescence hygrometers, J. Geophys. Res., 104, 1807–1816, 1999.