[en] Images of the nightside limb of Venus have been obtained in the northern hemisphere with the VIRTIS multispectral infrared imager on board Venus Express between April 2006 and October 2008. We analyze the latitudinal distribution of the O2(a1D) airglow limb profiles at 1.27 lm to characterize its distribution and variability. We show that the instantaneous structure of the emission is very different from the statistical global view of an enhanced emission near the equator, decreasing in brightness and slightly increasing in altitude toward the poles. The peak intensity of the limb profiles varies by a factor up to 50 between the brightest spots and the darkest regions. The bright airglow spots correspond to regions of enhanced downward flow of oxygen atoms originating from the dayside. Considerable variations in brightness and morphology are observed in the altitude–latitudinal distribution over a 24-h period. Analysis of the limb profiles indicates that secondary airglow peaks located at altitudes higher than the mean value of 96 km are observed on about 30% of the latitudinal cuts, but they are concentrated in narrow latitude areas extending over a few hundred kilometers. Most of them occur in transition regions between two altitude regimes in the 50 to 60 N region, possibly associated with the drop of the cloud top altitude observed equatorward of the ‘‘cold collar’’. We interpret these results as an indication that
the strength of vertical transport in this mesosphere–thermosphere transition region is very variable both in location and time. This variability, also observed in nadir airglow images and wind measurements, is a key characteristic of the mesosphere–thermosphere transition region. It may be caused by fluctuations of the global day-to-night circulation generated by gravity waves. We show with a one dimensional model that local enhancements of eddy transport is a possibility. This variability is currently not accounted for by global circulation models that predict a single stable region of enhanced airglow in the vicinity of the antisolar point.
Research center :
Laboratoire de Physique Atmosphérique et Planétaire
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Gérard, Jean-Claude ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Département d'astrophys., géophysique et océanographie (AGO)
Soret, Lauriane ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
Piccioni, Giuseppe; IAPS > INAF
Drossart, Pierre; Observatoire de Paris > LESIA
Language :
English
Title :
Latitudinal structure of the Venus O2 infrared airglow: A signature of small-scale dynamical processes in the upper atmosphere
Alexander M.J. A mechanism for the Venus thermospheric superrotation. Geophys. Res. Lett. 1992, 22:2207-2210.
Alexander M.J., Dunkerton T.J. A spectral parameterization of mean-flow forcing due to breaking gravity waves. J. Atmos. Sci. 1999, 56:4167-4182.
Allen D., Crisp D., Meadows V.S. Variable oxygen airglow on Venus as a probe of atmospheric dynamics. Nature 1992, 359:516-519.
Altieri, F., Migliorini, A., Zasova, L., Shakun, A., Piccioni, G., Bellucci, G., 2014. Modeling of VIRTIS/VEX O2(a1δg) nightglow profiles affected by the propagation of gravity waves in the Venus upper mesosphere. J. Geophys. Res. (submitted for publication).
Bailey J., Chamberlain S., Crisp D., Meadows V.S. Near infrared imaging spectroscopy of Venus with the Anglo-Australian Telescope. Icarus 2008, 56:1385-1390.
Bougher S.W., Borucki W.J. Venus O2 visible and IR nightglow: Implications for lower thermosphere dynamics and chemistry. J. Geophys. Res. 1994, 99:3759-3776.
Bougher S.W., Roble R.G.E., Dickinson R.E., Ridley E.C. Venus mesosphere and thermosphere. III-Three-dimensional general circulation with coupled dynamics and composition. Icarus 1988, 73:545-573.
Bougher S.W., Gérard J.C.A.I.F., Stewart A.I.F., Fesen C.G. The Venus nitric oxide night airglow: Model calculations based on the Venus thermospheric general circulation model. J. Geophys. Res. 1990, 95:6271-6284. 10.1029/JA095iA05p06271.
Brecht A.S., Bougher S.W., Gérard J.-C., Parkinson C.D., Rafkin S., Foster B. Understanding the variability of nightside temperatures, NO UV and O2 IR nightglow emissions in the Venus upper atmosphere. J. Geophys. Res. 2011, 116:8004. 10.1029/2010JE003770.
Brecht A., Bougher S.W., Gérard J.-C., Soret L. Atomic oxygen distributions in the Venus thermosphere: Comparisons between Venus Express observations and global model simulations. Icarus 2012, 217:759-766.
Clancy R.T., Sandor B.J., Moriarty-Schieven G. Circulation of the Venus upper mesosphere/lower thermosphere: Doppler wind measurements from 2001-2009 inferior conjunction, sub-millimeter CO absorption line observations. Icarus 2012, 217:794-812.
Clancy R.T., Sandor B.J., Moriarty-Schieven G. Thermal structure and CO distribution for the Venus mesosphere/lower thermosphere: 2001-2009 inferior conjunction sub-millimeter CO absorption line observations. Icarus 2012, 217:779-793.
Collet A., Cox C., Gérard J.C. Two-dimensional time-dependent model of the transport of minor species in the Venus night side upper atmosphere. Planet. Space Sci. 2010, 58:1857-1867.
Connes P., Noxon J.F., Traub W.A., Carleton N.P. O2(1δ) emission in the day and night airglow of Venus. Astrophys. J. 1979, 233:29-32.
Crisp D., Meadows V.S., Bézard B., deBergh C., Maillard J.P., Mills F.P. Ground-based near-infrared observations of the Venus nightside: 1.27μm O2(a1δg) airglow from the upper atmosphere. J. Geophys. Res. 1996, 101:4577-4593.
Dickinson R.E., Ridley E.C. Venus mesosphere and thermosphere temperature structure: II. Day-night variations. Icarus 1977, 30:163-178.
Drossart P., et al. Scientific goals for the observation of Venus by VIRTIS on ESA/Venus Express mission. Planet. Space Sci. 2007, 55:1653-1672.
Drossart P., et al. Infrared spectral imaging observations of Venus by VIRTIS reveal a dynamical upper atmosphere. Nature 2007, 450:641-645.
Garcia R.F., Drossart P., Piccioni G., López-Valverde M., Occhipinti G. Gravity waves in the upper atmosphere of Venus revealed by CO2 nonlocal thermodynamic equilibrium emissions. J. Geophys. Res. 2009, 114:E00B32. 10.1029/2008JE003073.
Gérard J.-C., Stewart A.I.F., Bougher S.W. The altitude distribution of the Venus ultraviolet airglow and implications on vertical transport. Geophys. Res. Lett. 1981, 8:633-636.
Gérard J.-C., Cox C., Saglam A., Bertaux J.-L., Villard E., Nehmé C. Limb observations of the ultraviolet nitric oxide nightglow with SPICAV on board Venus Express. J. Geophys. Res. 2008, 113:E00B03. 10.1029/2008JE003078.
Gérard J.-C., Saglam A., Piccioni G., Drossart P., Montmessin F., Bertaux J.-L. Atomic oxygen distribution in the Venus mesosphere from observations of O2 infrared airglow by VIRTIS-Venus Express. Icarus 2009, 199:264-272.
Gérard J.-C., et al. Concurrent observations of the ultraviolet nitric oxide and infrared O2 nightglow emissions with Venus Express. J. Geophys. Res. 2009, 114:E00B44.
Gérard J.-C., Soret L., Saglam A., Piccioni G., Drossart P. The distributions of the OH Meinel and O2(a1δ-X3σ) nightglow emissions in the Venus mesosphere based on VIRTIS observations. Adv. Space Res. 2010, 45:1268-1275.
Gérard J.-C., Soret L., Piccioni G., Drossart P. Spatial correlation of OH Meinel and O2 infrared atmospheric nightglow emissions observed with VIRTIS-M on board Venus Express. Icarus 2012, 217:813-817.
Hoshino N., Fujiwara H., Takagi M., Takahashi Y., Kasaba Y. Characteristics of planetary-scale waves simulated by a new Venusian mesosphere and thermosphere general circulation model. Icarus 2012, 217:818-830.
Hueso R., et al. Morphology and dynamics of Venus oxygen airglow from Venus Express/Visible and Infrared Thermal Imaging Spectrometer observations. J. Geophys. Res. 2008, 113:E00B02.
Huestis D.L., et al. Cross sections and reaction rates for comparative planetary aeronomy. Space Sci. Rev. 2008, 139:63-105.
Ignatiev N.I., et al. Altimetry of the Venus cloud tops from the Venus Express observations. J. Geophys. Res. 2009, 114:E00B43. 10.1029/2008JE003320.
Kasprzak W.T., Niemann H.B., Hedin A.E., Bougher S.W., Hunten D.M. Neutral composition measurements by the Pioneer Venus Neutral Mass Spectrometer during Orbiter re-entry. Geophys. Res. Lett. 1993, 20:2747-2750. 10.1029/93GL02241.
Krasnopolsky V.A. Venus night airglow: Ground-based detection of OH, observations of O2 emissions, and photochemical model. Icarus 2010, 207:17-27.
Krasnopolsky V.A. Nighttime photochemical model and night airglow on Venus. Planet. Space Sci. 2013, 85:78-88.
Lellouch E., Paubert G., Moreno R., Moullet A. Monitoring Venus' mesospheric winds in support of Venus Express: IRAM 30-m and APEX observations. Planet. Space Sci. 2008, 56:1355-1367.
Migliorini A., Piccioni G., Gérard J.-C., Soret L., Slanger T.G., Politi R., Snels M., Drossart P., Nuccilli F. The characteristics of the O2 Herzberg II and Chamberlain bands observed with VIRTIS/Venus Express. Icarus 2013, 223:609-614.
Nair H., Allen M., Anbar A.D., Yung Y.L. A photochemical model of the martian atmosphere. Icarus 1994, 111:124-150.
Niemann H.B., Kasprzak W.T., Hedin A.E., Hunten D.M., Spencer N.W. Mass spectrometric measurements of the neutral gas composition of the thermosphere and exosphere of Venus. J. Geophys. Res. 1980, 85:7817-7827. 10.1029/JA085iA13p07817.
Ohtsuki S., et al. Distributions of the Venus 1.27μm O2 airglow and rotational temperature. Planet. Space Sci. 2008, 56:1391-1398.
Piccioni, et al. South-polar features on Venus similar to those near the north pole. Nature 2007, 450:637-640.
Piccioni G., et al. Near-IR oxygen nightglow observed by VIRTIS in the Venus upper atmosphere. J. Geophys. Res. 2009, 114. 10.1029/2008je003133.
Royer E., Montmessin F., Bertaux J.L. NO emissions as observed by SPICAV during stellar occultations. Planet. Space Sci. 2010, 58:1314-1326.
Sander et al., 2003. Chemical Kinetics and Photochemical Data for use in Atmospheric Studies. Evaluation Number 14. JPL Publication 02-25.
Schubert, G. et al., 2007. Venus Atmosphere: A Continuing Enigma, Exploring Venus as a Terrestrial Planet. American Geophysical Union, pp. 101-120.
Soret L., Gérard J.-C., Piccioni G., Drossart P. Venus OH nightglow distribution based on VIRTIS limb observations from Venus Express. Geophys. Res. Lett. 2010, 37:L06805. 10.1029/2010GL042377.
Soret L., Gérard J.C., Montmessin F., Piccioni G., Drossart P., Bertaux J.L. Atomic oxygen on the Venus nightside: Global distribution deduced from airglow mapping. Icarus 2012, 217:849-855.
Soret, L., Gérard, J.C., Piccioni, G., Drossart, P., 2014. Time variations of O2(a1δ) nightglow spots on the Venus nightside and dynamics of the upper mesosphere. Icarus (in press). doi:10.1016/j.icarus.2014.03.034.
Stewart A.I.F., Gérard J.C., Rusch D.W., Bougher S.W. Morphology of the Venus ultraviolet night airglow. J. Geophys. Res. 1980, 85:7861-7870. 10.1029/JA085iA13p07861.
Stiepen A., Gérard J.-C., Dumont M., Cox C., Bertaux J.-L. Venus nitric oxide nightglow mapping from SPICAV nadir observations. Icarus 2013, 226:428-436.
Svedhem H., et al. Venus Express-The first European mission to Venus. Planet. Space Sci. 2007, 55:1636-1652.
Taylor F., et al. Structure and meteorology of the middle atmosphere of Venus: Infrared remote sensing from the Pioneer orbiter. J. Geophys. Res. 1980, 85:7963-8006. 10.1029/JA085iA13p07963.
Titov D.V., et al. Venus Express science planning. Planet. Space Sci. 2006, 54:1279-1297.
Von Zahn U., Fricke K.H., Hunten D.M., Krankowsky D., Mauersberger K., Nier A.O. The upper atmosphere of Venus during morning conditions. J. Geophys. Res. 1980, 85:7829-7840. 10.1029/JA085iA13p07829.
Zalucha A.M., Brecht A.S., Rafkin S., Bougher S.W.M., Alexander J. Incorporation of a gravity wave momentum deposition parameterization into the Venus Thermosphere General Circulation Model (VTGCM). J. Geophys. Res. 2013, 118:147-160. 10.1029/2012JE004168.
Zhang S., Bougher S.W., Alexander M.J. The impact of gravity waves on the Venus thermosphere and O2 IR nightglow. J. Geophys. Res. 1996, 101:23195-23205. 10.1029/96JE02035.