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J.Peralta, D.Luz, P.Machado CAAUL/Observatorio Astronómico de Lisboa (Universidade de Lisboa, PORTUGAL) Contribution from simultaneous wind measurements with VMC and ground-based observations
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Global-scale Waves: Tides -Persistent global oscillations found in wind, temperature, pressure, etc… -Global-scale atmospheric gravity waves excited by different sources.
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K=2 and K=4. Mean Amplitudes: ~ 2 m/s [K=2] ~ 5 m/s [K=4] (≤ 20% zonal comp.) K=4 dominant at lower latitudes. Retrograde acceleration at midday. Solar Tides in the Zonal Wind
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K=1. Mean Amplitudes: ~ 6 m/s [K=1] (>>100% merid. wind) Variations with the Latitude. Poleward acceleration at midday. K=1. Mean Amplitudes: ~ 6 m/s [K=1] (>>100% merid. wind) Variations with the Latitude. Poleward acceleration at midday. Solar Tides in the Meridional Wind
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Zonal Disturbances: Effect weaker than meridional. Absence for Diurnal Tide. Zonal Disturbances: Effect weaker than meridional. Absence for Diurnal Tide. Diurnal Tides: Main implications Meridional Disturbances: Strong effect of Diurnal Tide. DAY: Poleward acceleration NIGHT:Equatorward acceleration Meridional Disturbances: Strong effect of Diurnal Tide. DAY: Poleward acceleration NIGHT:Equatorward acceleration
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Diurnal Tides: Spatial Structure Wave fronts matching lines of constant SZA explains absence of K=1 on Zonal Wind.
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Mesoscale Waves: Cloud Tops
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Mesoscale Waves: Lower Clouds
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Mesoscale Waves: Characterization Packet Lenght Wavelength Packet Width Packet Orientation Phase Velocity Average Zonal Wind Packet Location
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Role of Ground-based Observations concerning the Waves GLOBAL-SCALE: Winds from Doppler technique allow accuracy enough to measure Tidal effects. Characterize Solar Tide at lower latitudes. MESOSCALE WAVES: Nowadays enough spatial resolution to resolve mesoscale wave effect on winds. Waves could be the reason for the wind disturbances. (Machado, 2012)
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Simultaneous Wind Measurements Ground-based and Remote Sensing (I) GROUND-BASED: ESPaDOnS high-resolution echelle spectrograph [DOPPLER EFFECT] REMOTE SENSING (VEX): VMC Camera with an UV filter to sense cloud tops [CLOUD TRACKING] Simultanous Observations: (ongoing work by Machado et al.) 2007 May 24 (20 VMC images) 2007 July 2-4 (8 VMC images) 2007 Sept 30 (11 VMC images)
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Simultaneous Wind Measurements Ground-based and Remote Sensing (II) GROUND-BASED: TNG/NICS (NIr Camera Spectrometer) to sense the nightside lower clouds [CLOUD TRACKING] REMOTE SENSING (VEX): VMC Camera with an UV filter to sense cloud tops [CLOUD TRACKING] Principal Investigator: D.Luz Images to be taken 2012 July 6-21 3D Winds after VIRTIS-IR failure Principal Investigator: D.Luz Images to be taken 2012 July 6-21 3D Winds after VIRTIS-IR failure
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Simultaneous Wind Measurements Ground-based and Remote Sensing (III) GROUND-BASED: YET TO BE CONFIRMED ! [DOPPLER EFFECT] REMOTE SENSING (VEX): SOIR IR high-resolution spectrometer to sense cloud tops and mesosphere [DOPPLER EFFECT] Ongoing work by J.Peralta, D.Luz, P.Machado, T.Widemann, A.Mahieux and A.C. Vandaele. First fine characterization of the circulation in the upper atmosphere. Ongoing work by J.Peralta, D.Luz, P.Machado, T.Widemann, A.Mahieux and A.C. Vandaele. First fine characterization of the circulation in the upper atmosphere. ?
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