Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 6 12 2006 10.5194/acp-6-4577-2006 http://www.atmos-chem-phys.net/6/4577/2006/ http://www.atmos-chem-phys.net/6/4577/2006/acp-6-4577-2006.html http://www.atmos-chem-phys.net/6/4577/2006/acp-6-4577-2006.pdf 4577 4589 2006-10-12 Mesoscale temperature fluctuations in the stratosphere B. L. Gary blgary@umich.edu Jet Propulsion Laboratory, Pasadena, CA 91109, 5320 E. Calle Manzana, Hereford, AZ 85615, USA An airborne instrument that measures altitude temperature profiles is ideally suited for the task of characterizing statistical properties of the vertical displacement of isentrope surfaces. Prior measurements of temperature fluctuations during level flight could not be used to infer isentrope altitude variations because lapse rate information was missing. The Microwave Temperature Profiler instrument, which includes lapse rate measurements at flight level as a part of temperature profiles, has been used on hundreds of flights to produce altitude versus ground track cross-sections of potential temperature. These cross-sections show isentrope altitude variations with a horizontal resolution of ~3 km for a >6 km altitude region. An airborne isentrope-altitude cross-section (IAC) can be compared with a counterpart IAC generated from synoptic scale data, based on radiosondes and satellite instruments, in order to assess differences between the altitudes of isentrope surfaces sampled at mesoscale versus synoptic scale. It has been found that the synoptic scale isentropes fail to capture a significant component of vertical displacement of isentrope surfaces, especially in the vicinity of jet streams. Under the assumptions that air parcels flow along isentrope surfaces, and change temperature adiabatically while undergoing altitude displacements, it is possible to compute mesoscale temperature fluctuations that are not present in synoptic scale back trajectory parcel temperature histories. It has been found that the magnitude of the mesoscale component of temperature fluctuations varies with altitude, season, latitude and underlying topography. A model for these dependences is presented, which shows, for example, that mesoscale temperature fluctuations increase with altitude in a systematic way, are greatest over mountainous terrain, and are greater at polar latitudes during winter. Bacmeister, J. T. and Gary, B. L.: Small-Scale Waves Encountered During AASE, Geophys. Res. Lett., 17, 349–352, 1990. Bacmeister, J. T.: Mountain-Wave Drag in the Stratosphere and Mesosphere Inferred from Observed Winds and a Simple Mountain Wave Parameterization Scheme, J. Atmos. Sci., 50, 377–399, 1993. Browell, E. V.: Differential Absorption Lidar Sensing of Ozone, Proc. IEEE, 77, 419–432, 1989. Carlsaw, K. S., Wirth, M., Tsias, A., Luo, B. P., Doernbrack, A., Leutbecher, M., Volkert, H., Renger, W., Bacmeister, J. T., Reimer, E., and Peter, T.: Increased stratospheric ozone depletion due to mountain-induced atmospheric waves, Nature, 391(6668), 675–678, doi:10.1038/35589, 1998. 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, 16 757–16 765, 1989. Doernbrack, A., Birner, T., Fix, A., Flentje, H., Meister, A., Schmid, H., Browell, E., and Mahoney, M. J.: Evidence for Inertia-Gravity Waves Forming Polar Stratospheric Clouds Over Scandinavia, J. Geophys. Res., 107(D20), 8287, doi:10.1029/2001JD000452, 2002. Farman, J. C., Gardner, B. G., and Shanklin, J. D.: Large Losses of Total Ozone in Antarctica Reveal Seasonal ClOx/Nox Interaction, Nature, 315, 207–210, 1985. Fueglistaler, S., Buss, S., Luo, B. P., Wernli, H., Flentje, H., Hostettler, C. A., Poole, L. R., Carslaw, K. S., and Peter, T.: Detailed Modeling of Mountain Wave PSCs, Atmos. Chem. Phys., 3, 697–712, 2003. Gage, K. S. and Nastrom, G. D.: Spectrum of Atmospheric Vertical Displacements and Spectrum of Conservative Scalar Passive Additives Due to Quasi-Horizontal Atmospheric Motions, J. Geophys. Res., 92, 13 211–13 216, 1986. Gao, R. S., Richard, E. C., Popp, P. J., et al.: Observational Evidence for the Role of Denitrification in Arctic Stratospheric Ozone Loss, Geophys. Rev. Lett., 28, 2879–2882, 2001. Gary, B. L.: Observational Results Using the Microwave Temperature Profiler During the Airborne Antarctic Ozone Experiment, J. Geophys. Res., 94, 11 223–11 231, 1989. Hoyle, C. R., Luo, B. P., and Peter, T.: The Origin of High Ice Crystal Number Densities in Cirrus Clouds, J. Atmos. Sci., 62, 2568–2579, 2005. Karcher, B. and Strom, J.: The roles of dynamical variability and aerosols in cirrus cloud formation, Atmos. Chem. Phys., 3, 823–838, 2003. Lovejoy, S., Schertzer, D., and Tuck, A.: Fractal aircraft trajectories and nonclassical turbulent exponents, Phys. Rev. E, 70, 036306, 2004. Mandelbrot, B. B.: Fractals and 1/f Noise, Berlin, Springer, 1998. 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. Mahoney, M. J. and Gary, B.: DC-8 MTP Calibration for SOLVE-2, SOLVE-2/Vintersol Science Team Meeting, Orlando, FL, 21–24 October 2003. Murphy, D. M. and Gary, B. L.: Mesoscale Temperature Fluctuations and Polar Stratospheric Clouds, J. Atmos. Sci., 52, 1753–1760, 1995. Nastrom, G. D. and Gage, K. S.: A Climatology of Atmospheric Wave Number Spectra Observed by Commercial Aircraft, J. Atmos. Sci., 42, 950–960, 1985. Schoeberl, M., Newman, P., and Lait, L.: Goddard Space Flight Center Code 916, XS mission exchange files, 1991 and 1994. Scott, S. G., Bui, T. P., Chan, K. R., and Bowen, S. W.: The Meteorological Measurement System on the NASA ER-2 Aircraft, J. Atmos. Oceanic Technol., 7, 525–540, 1990. Tabazadeh, A., Toon, O. B., Gary, B. L., Bacmeister, J. T., and Schoeberl, M. R.: Observational Constraints on the Formation of Type Ia Polar Stratospheric Clouds, Geophys. Res. Lett., 23, 2109–2112, 1996. Tuck, A. F., Hovde, S. J., and Bui, T. P.: Scale invariance in jet streams: ER-2 data around the lower-stratosphere polar night vortex, Quart. J. Meteorol. Soc., 130, 2423–2444, 2004. Voigt, C., Tsias, A., Doernbrack, A., Meilinger, S., Luo, B., Schreiner, J., Larsen, N., Mauersberger, K., and Peter, T.: Non-equilibrium compositions of liquid polar stratospheric clouds in gravity waves, Geophys. Res. Lett., 27(23), 3873–3876, doi:10/1029/2000GL012168, 2000. Wofsy, S. C., Gobbi, G. P., Salawich, R., and McElroy, M. B.: Vapor Pressure of Solid Hydrates of Nitric Acid: Implications for Polar Stratospheric Clouds, Science, 259, 71–74, 1993. Wu, D. L. and Waters, J. W.: Satellite Observations of Atmospheric Variances: A Possible Indication of Gravity Waves, Geophys. Res. Lett., 23, 3631–3634, 1996. Wu, D. L. and Waters, J. W.: Gravity-Wave-Scale Temperature Fluctuations Seen by the UARS MLS, Geophys. Res. Lett., 23, 3289–3292, 1996.