Editorial Type:
Article
Article Type:
Research Article

Convectively Generated Internal Gravity Waves in the Lower Atmosphere of Venus. Part II: Mean Wind Shear and Wave–Mean Flow Interaction

R. David Baker Department of Earth and Space Sciences, University of California, Los Angeles, Los Angeles, California

Search for other papers by R. David Baker in
Current site
Google Scholar
PubMed Close
,
Gerald Schubert Department of Earth and Space Sciences, University of California, Los Angeles, Los Angeles, California

Search for other papers by Gerald Schubert in
Current site
Google Scholar
PubMed Close
, and
Philip W. Jones Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico

Search for other papers by Philip W. Jones in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Jan 2000
DOI:
https://doi.org/10.1175/1520-0469(2000)057<0200:CGIGWI>2.0.CO;2
Page(s):
200–215
Restricted access

Abstract

This paper is the second of a two-part study that numerically investigates internal gravity wave generation by convection in the lower atmosphere of Venus. Part I of this study considers gravity wave generation and propagation in the absence of mean wind shear. In Part II, the Venus westward superrotation is included, and wave–mean flow interaction is assessed.

Both lower-atmosphere convection and cloud-level convection play active roles in the dynamics of the stable layer from 31- to 47-km altitude when mean wind shear is present. This result contrasts with the simulation without mean wind shear presented in Part I where cloud-level convection was primarily responsible for gravity wave generation in the stable layer. In the presence of mean wind shear, upward entrainment from lower-atmosphere convection and downward penetration from cloud-level convection are comparable in magnitude. Convectively generated internal gravity waves have horizontal wavelengths (∼25–30 km) comparable to horizontal scales in both convection layers. Quasi-stationary gravity waves (with respect to the lower convection layer) occur in the lower part of the stable layer, while both eastward- and westward-propagating waves generated by cloud-level convection exist in the upper part of the stable layer. Simulated wave amplitudes and vertical wavelengths agree well with observations. Eastward-propagating waves generated by cloud-level convection experience critical level absorption in the stable layer and thus decelerate the Venus westward superrotation below the clouds. The deceleration is comparable in magnitude to zonal accelerations above the clouds by thermal tides.

* Current affiliation: NASA Goddard Space Flight Center, Universities Space Research Association, Greenbelt, Maryland.

Additional affiliation: Institute of Geophysics and Planetary Physics, University of California, Los Angeles, Los Angeles, California.

Corresponding author address: Dr. R. David Baker, NASA Goddard Space Flight Center, Code 912, Universities Space Research Association, Greenbelt, MD 20771.

Email: rbaker@agnes.gsfc.nasa.gov

Abstract

This paper is the second of a two-part study that numerically investigates internal gravity wave generation by convection in the lower atmosphere of Venus. Part I of this study considers gravity wave generation and propagation in the absence of mean wind shear. In Part II, the Venus westward superrotation is included, and wave–mean flow interaction is assessed.

Both lower-atmosphere convection and cloud-level convection play active roles in the dynamics of the stable layer from 31- to 47-km altitude when mean wind shear is present. This result contrasts with the simulation without mean wind shear presented in Part I where cloud-level convection was primarily responsible for gravity wave generation in the stable layer. In the presence of mean wind shear, upward entrainment from lower-atmosphere convection and downward penetration from cloud-level convection are comparable in magnitude. Convectively generated internal gravity waves have horizontal wavelengths (∼25–30 km) comparable to horizontal scales in both convection layers. Quasi-stationary gravity waves (with respect to the lower convection layer) occur in the lower part of the stable layer, while both eastward- and westward-propagating waves generated by cloud-level convection exist in the upper part of the stable layer. Simulated wave amplitudes and vertical wavelengths agree well with observations. Eastward-propagating waves generated by cloud-level convection experience critical level absorption in the stable layer and thus decelerate the Venus westward superrotation below the clouds. The deceleration is comparable in magnitude to zonal accelerations above the clouds by thermal tides.

* Current affiliation: NASA Goddard Space Flight Center, Universities Space Research Association, Greenbelt, Maryland.

Additional affiliation: Institute of Geophysics and Planetary Physics, University of California, Los Angeles, Los Angeles, California.

Corresponding author address: Dr. R. David Baker, NASA Goddard Space Flight Center, Code 912, Universities Space Research Association, Greenbelt, MD 20771.

Email: rbaker@agnes.gsfc.nasa.gov

Save
Cover Journal of the Atmospheric Sciences
Journal of the Atmospheric Sciences

  • Alexander, M. J., and J. R. Holton, 1997: A model study of zonal forcing in the equatorial stratosphere by convectively induced gravity waves. J. Atmos. Sci.,54, 408–419.

  • Andreassen, O., C. E. Wasberg, D. C. Fritts, and J. R. Isler, 1994: Gravity wave breaking in two and three dimensions. 1. Model description and comparison of two-dimensional evolutions. J. Geophys. Res.,99, 8095–8108.

  • Asai, T., 1970: Three-dimensional features of thermal convection in a plane Couette flow. J. Meteor. Soc. Japan,48, 18–29.

  • Baker, R. D., and G. Schubert, 1992: Cellular convection in the atmosphere of Venus. Nature,355, 710–712.

  • ——, ——, and P. W. Jones, 1998: Cloud-level penetrative compressible convection in the Venus atmosphere. J. Atmos. Sci.,55, 3–18.

  • ——, ——, and ——, 1999: High Rayleigh number compressible convection in Venus’ atmosphere: Penetration, entrainment, and turbulence. J. Geophys. Res.,104, 3815–3832.

  • ——, ——, and ——, 2000: Convectively generated internal gravity waves in the lower atmosphere of Venus. Part I: No wind shear. J. Atmos. Sci.,57, 184–199.

  • Booker, J. R., and F. B. Bretherton, 1967: The critical layer for internal gravity waves in a shear flow. J. Fluid Mech.,27, 513–539.

  • Clark, T. L., T. Hauf, and J. P. Kuettner, 1986: Convectively forced internal gravity waves: Results from two-dimensional numerical experiments. Quart. J. Roy. Meteor. Soc.,112, 899–925.

  • Counselman, C. C. I., S. A. Gourevitch, R. W. King, G. B. Loriot, and E. S. Ginsberg, 1980: Zonal and meridional circulation of the lower atmosphere of Venus determined by radio interferometry. J. Geophys. Res.,85, 8026–8030.

  • Del Genio, A. D., and W. Zhou, 1996: Simulations of superrotation on slowly rotating planets: Sensitivity to rotation and initial condition. Icarus,120, 332–343.

  • ——, ——, and T. P. Eichler, 1993: Equatorial superrotation in a slowly rotating GCM—Implications for Titan and Venus. Icarus,101, 1–17.

  • Droegemeier, K. K., and R. B. Wilhelmson, 1987: Numerical simulation of thunderstorm outflow dynamics. Part I: Outflow sensitivity experiments and turbulence dynamics. J. Atmos. Sci.,44, 1180–1210.

  • Eliassen, A., and E. Palm, 1961: On the transfer of energy in stationary mountain waves. Geofys. Publ.,22, 1–23.

  • Esposito, L. W., 1984: Sulfur dioxide: Episodic injection shows evidence for active Venus volcanism. Science,223, 1072–1074.

  • Fovell, R., D. Durran, and J. R. Holton, 1992: Numerical simulations of convectively generated stratospheric gravity waves. J. Atmos. Sci.,49, 1427–1442.

  • Gierasch, P., 1975: Meridional circulation and the maintenance of the Venus atmospheric rotation. J. Atmos. Sci.,32, 1038–1044.

  • ——, and Coauthors, 1997: The general circulation of the Venus atmosphere: An assessment. Venus II, S. W. Bougher, D. M. Hunten, and R. J. Phillips, Eds., University of Arizona Press, 459–500.

  • Hauf, T., and T. L. Clark, 1989: Three-dimensional numerical experiments on convectively forced internal gravity waves. Quart. J. Roy. Meteor. Soc.,115, 309–333.

  • Hinson, D. P., and J. M. Jenkins, 1995: Magellan radio occultation measurements of atmospheric waves on Venus. Icarus,114, 310–327.

  • Holton, J. R., 1979: An Introduction to Dynamic Meteorology. 2d ed. Academic Press, 391 pp.

  • ——, and R. S. Lindzen, 1972: An updated theory for the quasi-biennial cycle of the tropical stratosphere. J. Atmos. Sci.,29, 1076–1080.

  • Hou, A. Y., and B. F. Farrell, 1987: Superrotation induced by critical-level absorption of gravity waves on Venus: An assessment. J. Atmos. Sci.,44, 1049–1061.

  • Hurlburt, N. E., J. Toomre, and J. M. Massaguer, 1986: Nonlinear compressible convection penetrating into stable layers and producing internal gravity waves. Astrophys. J.,311, 563–577.

  • Jenkins, J. M., P. G. Steffes, D. P. Hinson, J. D. Twicken, and G. L. Tyler, 1994: Radio occultation studies of the Venus atmosphere with the Magellan spacecraft 2. Results from the October 1991 experiments. Icarus,110, 79–94.

  • Kerzhanovich, V. V., and M. Y. Marov, 1983: The atmospheric dynamics of Venus according to Doppler measurements by the Venera entry probes. Venus, D. M. Hunten et al., Eds., University of Arizona Press, 766–778.

  • Knollenburg, R. G., and D. M. Hunten, 1980: The microphysics of the clouds of Venus: Results of the Pioneer Venus particle size spectrometer experiment. J. Geophys. Res.,85, 8039–8058.

  • Leroy, S. S., and A. P. Ingersoll, 1995: Convective generation of gravity waves in Venus’s atmosphere: Gravity wave spectrum and momentum transport. J. Atmos. Sci.,52, 3717–3737.

  • Lindzen, R. S., 1990: Dynamics in Atmospheric Physics. Cambridge University Press, 310 pp.

  • Mason, P. J., and R. I. Sykes, 1982: A two-dimensional numerical study of horizontal roll vortices in an inversion capped boundary layer. Quart. J. Roy. Meteor. Soc.,108, 801–823.

  • Newman, M., and C. Leovy, 1992: Maintenance of strong rotational winds in Venus’ middle atmosphere by thermal tides. Science,257, 647–650.

  • Schubert, G., 1983: General circulation and the dynamical state of the Venus atmosphere. Venus, D. M. Hunten et al., Eds. University of Arizona Press, 681–765.

  • Seiff, A., D. B. Kirk, R. E. Young, R. C. Blanchard, J. T. Findlay, G. M. Kelly, and S. C. Sommer, 1980: Measurements of thermal structure and thermal contrasts in the atmosphere of Venus and related dynamical observations: Results from the four Pioneer Venus probes. J. Geophys. Res.,85, 7903–7933.

  • ——, R. E. Young, R. Haberle, and H. Houben, 1992: The evidences of waves in the atmospheres of Venus and Mars. Venus and Mars: Atmospheres, Ionospheres, and Solar Wind Interactions, Geophys. Monogr., No. 66, Amer. Geophys. Union, 73–89.

  • Walterscheid, R. L., and G. Schubert, 1990: Nonlinear evolution of an upward propagating gravity wave: Overturning, convection, transience and turbulence. J. Atmos. Sci.,47, 101–125.

  • Woo, R., J. W. Armstrong, and A. J. Kliore, 1982: Small-scale turbulence in the atmosphere of Venus. Icarus,52, 335–345.

  • Young, R. E., R. L. Walterscheid, G. Schubert, A. Seiff, V. M. Linkin, and A. N. Lipatov, 1987: Characteristics of gravity waves generated by surface topography on Venus: Comparison with the VEGA balloon results. J. Atmos. Sci.,44, 2628–2639.

  • ——, ——, ——, L. Pfister, H. Houben, and D. L. Bindschadler, 1994: Characteristics of finite amplitude stationary gravity waves in the atmosphere of Venus. J. Atmos. Sci.,51, 1857–1875.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 283 67 5
PDF Downloads 116 33 2