Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 9 5 2009 10.5194/acpd-9-20631-2009 http://www.atmos-chem-phys-discuss.net/9/20631/2009/ http://www.atmos-chem-phys-discuss.net/9/20631/2009/acpd-9-20631-2009.html http://www.atmos-chem-phys-discuss.net/9/20631/2009/acpd-9-20631-2009.pdf 20631 20675 2009-10-01 Ice nucleation and cloud microphysical properties in tropical tropopause layer cirrus E. J. Jensen eric.j.jensen@nasa.gov L. Pfister T.-P. Bui P. Lawson D. Baumgardner NASA Ames Research Center, Moffett Field, CA, USA SPEC Inc., Boulder, CO, USA Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Mexico In past modeling studies, it has generally been assumed that the predominant mechanism for nucleation of ice in the uppermost troposphere is homogeneous freezing of aqueous aerosols. However, recent in situ and remote-sensing measurements of the properties of cirrus clouds at very low temperatures in the tropical tropopause layer (TTL) are broadly inconsistent with theoretial predictions based on the homogeneous freezing assumption. The nearly ubiquitous occurence of gravity waves in the TTL makes the predictions from homogeneous nucleation theory particularly difficult to reconcile with measurements. These measured properties include ice number concentrations, which are much lower than theory predicts; ice crystal size distributions, which are much broader than theory predicts; and cloud extinctions, which are much lower than theory predicts. Although other explanations are possible, one way to limit ice concentrations is to have on the order of 50 L^−1 effective ice nuclei (IN) that could nucleate ice at relatively low supersaturations. We suggest that ammonium sulfate particles, which would be dry much of the time in the cold TTL, are a potential IN candidate for TTL cirrus. Possible implications of the observed cloud microphysical properties for ice sedimentation, dehydration, and cloud persistence are also discussed. Abbatt,~J P D., Benz,~S., Cziczo,~D J., Kanji,~Z., Lohmann,~U., and Möhler,~O.: Solid ammonium sulfate aerosols as ice nuclei: A pathway for cirrus formation, Science, 313, 1770–1773, 2006. Ackerman,~T P., Liou,~K N., Valero,~F P., and Pfister,~L.: Heating rates in tropical anvils, J Atmos. Sci., 45, 1606–1623, 1988. Anselmo,~T., Clifton,~R., Hunt,~W., Lee,~K.-P., Murray,~T., Powell,~K., Rodier,~S D., Vaughan,~M., Chometter,~O., Viollier,~M., Hagolle,~O., Lifermann,~A., Garnier,~A., Pelon,~J., Currey,~J C., Pitts,~M., and Winker,~D.: Cloud-Aerosol Lidar Infrared Pathfinder Satellite Observations Data Management System Data Products Catalog, PC-SCI-503, 2007. Archuleta,~C M., DeMott,~P J., and Kreidenweis,~S M.: Ice nucleation by surrogates for atmospheric mineral dust and mineral dust/sulfate particles at cirrus temperatures, Atmos. Chem. Phys., 5, 2617–2634, 2005. Bacmeister,~J T., Eckermann,~S D., Newman,~P A., Lait,~L., Chan,~K R., Loewenstein,~M., Proffitt,~M H., and Gary,~B.: Stratospheric horizontal wavenumber spectra of winds, potential temperature, and atmospheric tracers observed by high altitude aircraft, J Geophys. Res., 101, 9441–9470, 1996. Baker,~B., Mo,~Q., Lawson,~R P., Korolev,~A., and O'Connor,~D.: Drop size distributions and the lack of small drops in RICO rain shafts, J. Atmos. Sci., 1, in press, 2009. Baumgardner,~D., Jonsson,~H., Dawson,~W., O'Connor,~D, and Newton,~R.: The cloud, aerosol and precipitation spectrometer (CAPS): A new instrument for cloud investigations, Atmos. Res., 59, 59–60, 2001. Borrmann,~S., Luo,~B., and Mischenko,~M.: Application of the T-matrix method to the measurement of aspherical (ellipsoidal) particles with forward scattering optical particle counters, J Aerosol. Sci., 31, 789–799, 2000. Brock,~C A., Hamill,~P., Wilson,~J C., Jonsson,~H H., and Chan,~K R.: Particle formation in the upper tropical troposphere: A source of nuclei for the stratospheric aerosol, Science, 270, 1650–1653, 1995. Chepfer,~H. and Noel,~V.: A tropical \qutNAT-like belt observed from space, Geophys. Res. Lett., 36, L03813, doi:10.1029/2008GL036 289, 2009. Comstock,~J M., Ackerman,~T P., and Mace,~G G.: Ground based remote sensing of tropical cirrus clouds at Nauru Island: Cloud statistics and radiative impacts, J Geophys. Res., 107, 4714, doi:10.1029/2002JD002 203, 2002. Corti,~T., Luo,~B P., Fu,~Q., Vömel,~H., and Peter,~T.: The impact of cirrus clouds on tropical troposphere-tostratosphere transport, Atmos. Chem. Phys., 6, 2539–2547, 2006. Davis,~S M., Hlavka,~D., Jensen,~E., Rosenlof,~K., Schmidt,~S., Borrmann,~S., Frey,~W., Lawson,~P., Vömel,~H., and Bui,~T.-P.: In situ and lidar observations of subvisible cirrus clouds during TC4, J Geophys. Res., submitted, 2009. Denning,~R F., Guidero,~S L., Parks,~G S., and Gary,~B L.: Instrument description of the airborne microwave temperature profiler, J Geophys. Res., 94, 16757–16765, 1989. Field,~P R., Wood,~R., Brown,~P R A., Kaye,~P H., Hirst,~E., and Greeaway,~R.: Ice particle interarrival times measured with a fast FSSP, J Atmos. Ocean. Tech., 20, 249–261, 2003. Field,~P R., Heymsfield,~A J., and Bansemer,~A.: Shattering and particle interarrival times measured by optical array probes in ice clouds, J Atmos. Ocean. Tech., 23, 1357–1371, 2006. Fritts,~D C. and Nastrom,~G D.: Sources of mesoscale variability of gravity waves. Part II: Frontal convective, and jet stream excitation, J. Atmos. Sci., 49, 111–127, 1992. Froyd, K. D., Murphy, D. M., Lawson, P., Baumgardner, D., and Herman, R. L.: Composition of cirrus-forming aerosols at the tropical tropopause, Atmos. Chem. Phys. Discuss., 9, 20347–20369, 2009a. Froyd,~K D., Murphy,~D M., Sanford,~T J., Thomson,~D S., Wilson,~J C., Pfister,~L., and Lait,~L.: Aerosol composition of the tropical upper troposphere, Atmos. Chem. Phys., 9, 4363–4385, 2009b. Fu,~Q., Hu,~Y., and Yang,~Q.: Identifying the top of the tropical tropopause layer from vertical mass flux analysis and CALIPSO lidar cloud observations, Geophys. Res. Lett., 34, L14813, doi:10.1029/2007GL030099, 2007. Fueglistaler,~S., Bonazzola,~M., Haynes,~P H., and Peter,~T.: Stratospheric water vapor predicted from the Lagrangian temperature history of air entering the stratosphere in the tropics, J Geophys. Res., 110, D08107, doi:10.1029/2004JD005516, 2005. Fueglistaler,~S., Dessler,~A E., Dunkerton,~T J., Folkins,~I., Fu,~Q., and Mote,~P W.: The tropical tropopause layer, Rev. Geophys., 47, RG1004, doi:10.1029/2008RG000267, 2008. Gensch,~I V., Bunz,~H., Baumgardner,~D G., Christensen,~L E., Fahey,~D W., Herman,~R L., Popp,~P J., Smith,~J B., Troy,~R F., Webster,~C R., Weinstock,~E M., Wilson,~J C., Peter,~T., and Krämer,~M.: Supersaturations, microphysics and nitric acid partitioning in a cold cirrus cloud observed during CR-AVE 2006: an observation-modelling intercomparison study, Environ. Res. Lett., 3, 1–9, 2008. Gettelman,~A., Randel,~W J., Wu,~F., and Massie,~S T.: Transport of water vapor in the tropical tropopause layer, Geophys. Res. Lett., 29, 1009, doi:10.1029/2001GL013818, 2002. Heymsfield,~A J.: Ice particles observed in a cirroform cloud at −85\unit\degree C and implications for polar stratospheric clouds, J Atmos. Sci., 43, 851–855, 1986. Heymsfield,~A J.: On measurements of small ice particles in clouds, Geophys. Res. Lett., 34, L23812, doi:10.1029/2007GL030951, 2007. Huffman,~G J., Adler,~R F., Bolvin,~D T., Gu,~G., Nelkin,~E J., Bowman,~K P., Hong,~Y., Stocker,~E F., and Wolff,~D B.: The TRMM Multi-satellite Precipitation Analysis: Quasi-global, multi-year, combined-sensor precipitation estimates at fine scale, J Hydrometeor., 8, 38–55, 2007. Jensen,~E J. and Drdla,~K.: Nitric acid concentrations near the tropical tropopause: Implications for the properties of tropical nitric acid trihydrate clouds, Geophys. Res. Lett., 29, D02207, doi:10.1029/2002GL015190, 2002. Jensen,~E J. and Pfister,~L.: Transport and freeze-drying in the tropical tropopause layer, J Geophys. Res., 109, L01808, doi:10.1029/2003JD004022, 2004. Jensen,~E J. and Toon,~O B.: Ice nucleation in the upper troposphere: Sensitivity to aerosol number density, temperature, and cooling rate, Geophys. Res. Lett., 21, 2019–2022, 1994. Jensen,~E J., Toon,~O B., Selkirk,~H B., Spinhirne,~J D., and Schoeberl,~M R.: On the formation and persistence of subvisible cirrus clouds near the tropical tropopause, J. Geophys. Res., 101, 21361–21375, 1996. Jensen,~E J., Pfister,~L., Ackerman,~A S., and Tabazadeh,~A.: 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, 17273–17252, 2001. Jensen,~E J., Pfister,~L., Bui,~T.-P., Weinheimer,~A., Weinstock,~E., Smith,~J., Pittmann,~J., Baumgardner,~D., and McGill,~M J.: Formation of a~tropopause cirrus layer observed over Florida during CRYSTALFACE, J Geophys. Res., 110, 4010, doi:10.1029/2004JD004671, 2005. Jensen,~E J., Pfister,~L., Bui,~T V., Lawson,~P., Baker,~B., Mo,~Q., Baumgardner,~D., Weinstock,~E M., Smith,~J B., Moyer,~E J., Hanisco,~T F., Sayres,~D S., Clair,~J M S., Alexander,~M J., Toon,~O B., and Smith,~J A.: Formation of large ($\simeq100\unit\mu m$) ice crystals near the tropical tropopause, Atmos. Chem. Phys., 8, 1621–1633, 2008. Jensen,~E J., Lawson,~P., Baker,~B., Pilson,~B., Mo,~Q., Heymsfield,~A., Bansemer,~A., Bui,~T.-P., McGill,~M., Hlavka,~D., Heymsfield,~G., Platnick,~S., Arnold,~T., and Tanelli,~S.: On the importance of small ice crystals in tropical anvil cirrus, Atmos. Chem. Phys., 9, 5519–5537, 2009. Kärcher,~B. and Lohmann,~U.: A~parameterization of cirrus cloud formation: Homogeneous freezing of supercooled aerosols, J Geophys. Res., 107, L10809, doi:10.1029/2001JD000470, 2002. Kärcher,~B. and Ström,~J.: The roles of dynamical variability and aerosols in cirrus cloud formation, Atmos. Chem. Phys., 3, 823–838, 2003. Kay,~J E. and Wood,~R.: Timescale analysis of aerosol sensitivity during homogeneous freezing and implications for upper tropospheric water budgets, Geophys. Res.Lett., 35, l10809, doi:10.1029/2007GL032628, 2008. Koop,~T., Luo,~B., 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., Boormann,~S., de Reus,~M., and Spichtinger,~P.: Ice supersaturations and cirrus cloud crystal numbers, Atmos. Chem. Phys., 9, 3505–3522, 2009. Lawson,~R P., O'Connor,~D., Zmarzly,~P., Weaver,~K., Baker,~B A., Mo,~Q., and Jonsson,~H.: The 2-D-S (Stereo) probe: Design and preliminary tests of a new airborne, high-speed, high-resolution imaging probe, J Atmos. Ocean. Tech., 23, 1462–1477, 2006. Lawson,~R P., Pilson,~B., Baker,~B A., Mo,~Q., Jensen,~E J., Pfister,~L., and Bui,~P.: Aircraft measurements of microphysical properties of subvisible cirrus clouds in the tropical tropopause layer, Atmos. Chem. Phys., 8, 1609–1620, 2008. Massie,~S., Gille,~J., Craig,~C., Khosravi,~R., Barnett,~J., and Read,~W.: HIRDLS and CALIPSO observations of tropical cirrus,~J. Geophys. Res., in press, 2009. McFarquhar,~G M., Heymsfield,~A J., Spinhirne,~J., and Hart,~B.: Thin and subvisual tropopause cirrus: Observations and radiative impacts, J Atmos. Sci., 57, 1841–1853, 2000. McFarquhar,~G M., Um,~J., Freer,~M., Baumgardner,~D., Kok,~G L., and Mace,~G.: The importance of small ice crystals to cirrus properties: Observations from the tropical warm pool international cloud experiment (TWP-ICE), Geophys. Res. Lett., 57, L13803, doi:10.1029/2007GL029865, 2007. Möhler,~O., Field,~P R., Connolly,~P., Benz,~S., Saathoff,~H., Schnaiter,~M., and Wagner,~R.: Efficiency of the deposition mode ice nucleation on mineral dust particles, Atmos. Chem. Phys., 6, 3007–3021, 2006. Möhler,~O., Benz,~S., Saathoff,~H., Schnaiter,~M., Wagner,~R., Schneider,~J., Walter,~S., Ebert,~V., and Wagner,~S.: The effect of organic coating on the heterogeneous ice nucleation efficiency of mineral dust aerosols, Environ. Res. Lett., 3, 1–8, 2008. Murphy,~D M.: Dehydration in cold clouds is enhanced by a~transition from cubic to hexagonal ice, Geophys. Res. Lett., 30, 2230, doi:10.1029/2003GL018566, 2003. Reagan,~J A., Wang,~X., and Osborn,~M T.: Spaceborne lidar calibration from cirrus and molecular backscatter returns, IEEE Trans. Geosci., 40, 2285–2290, 2002. Scott,~S G., Bui,~T P., Chan,~K R., and Bowen,~S W.: The meteorological measurement systemon the NASA ER-2 aircraft, J Atmos. Ocean. Tech., 7, 525–540, 1990. Selkirk,~H B.: The tropopause cold trap in the Australian monsoon during STEP$/$AMEX 1987, J Geophys. Res., 98, 8591–8610, 1993. Sherwood,~S C., Horinouchi,~T., and Zeleznik,~H A.: Convective impact on temperatures observed near the tropical tropopause, J Atmos. Sci., 60, 1847–1856, 2003. Spichtinger,~P. and Gierens,~K.: Modelling of cirrus clouds – Part 1b: Structuring cirrus clouds by dynamics, Atmos. Chem. Phys., 9, 707–719, 2009. Takahama,~S., Pathak,~R K., and Pandis,~S N.: Efflorescence transitions of ammonium sulfate particles coated with secondary organic aerosols, Environ. Sci. Technol., 41, 2289–2295, 2007. Wang,~P.-H., Minnis,~P., McCormick,~M P., Kent,~G S., and Skeens,~K M.: A~6-year climatology of cloud occurrence frequency from stratospheric aerosol and gas experiment II observations (1985–1990), J Geophys. Res., 101, 29407–29429, 1996. Wise,~M E., Baustian,~K J., and Tolbert,~M A.: Laboratory studies of ice formation pathways from ammonium sulfate particles, Atmos. Chem. Phys., 9, 1639–1646, 2009. Yang,~Q., Fu,~Q., and Hu,~Y.: Radiative impacts of clouds in the tropical tropopause layer, J Geophys. Res., in press, 2009. Young,~S A. and Vaughan,~M A.: The retrieval of profiles of particulate extinction from cloud aerosol lidar infrared pathfinder satillite observations (CALIPSO) data: Algorithm description, J Atmos. Ocean. Tech., 26, 1105–1119, 2009.