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Investigating impact of weather on atmosphere dynamics and troposphere-to-ionosphere energy transfer in Antarctic Peninsula. Analysis of weather factors influencing ionospheric disturbances and AGW conditions.
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Interaction between Atmospheric and Space Weather Systems A.V. Zalizovski Institute of Radio Astronomy, NAS, Ukraine. Chervonopraporna str., 4. Kharkiv Antarctic Peninsula is a very suitable area for experimental investigations of troposphere-to-ionosphere energy transfer because this place characterized by the extremely high cyclonic activity, quiet background of mid-latitude ionospheric disturbances, magnetic anomaly, and rapid variations in the total ozone content. Analysis of long-term data sets obtained at Akademik Vernadsky station (former Faraday) has allowed to discover numerous facts showing the weather impact on the dynamics of middle and upper atmosphere. Among them are the correlation between atmospheric fronts and occurrence of sporadic structures in the E and F ionospheric regions, influence of large-scale cyclones on the ozone hole location and geometry, impact of the ozone layer on the troposphere-to-ionosphere energy transfer, etc.
Where the troposphere impact on the ionosphere could be measured? • Atmospheric gravity waves (AGW) are the principal agent that can transfer the energy from troposphere. So, that should be the region with optimal… • Conditions for generation of AGW in the troposphere; • Conditions for energy transfer from movements of neutral atmosphere to the ionospheric currents and/or plasma characteristics; • Quiet background of ionospheric disturbances; • Conditions for propagation of AGW on the ionospheric heights.
Conditions for generation of AGW in the troposphere are the best in the cloud systems The radiation balance of the atmosphere Гилл А. Динамика атмосферы и океана/ А.Гилл– М: Мир, 1986 г. В 2-х т. Т.1– 397с.
Mechanism of energy transfer from the neutrals to the plasma movement is the ion drag Longitudinal distribution of efficiency of ion drag mechanism in the Northern and Southern hemispheres along the 65 degree of latitude
Antarctic Peninsula • Unique interference conditions • Big difference between geographic and geomagnetic latitudes • Middle geomagnetic latitudes • High cyclonic activity • Geomagnetic anomaly • Weddell sea anomaly • Quick variations of total ozone content at the spring time
Geographic coordinates: 65.25S, 64.27WGeomagnetic coordinates (CGM): 50S, 9 E Akademik Vernadsky station
Background variations of the environment parameters at the Vernadsky station Surface temperature Critical frequency of the ionosphere Weddell sea anomaly
Results of modeling of the global distribution of velocity of vertical transport of ionospheric plasma by thermospheric winds а) b) • Daily variations of critical frequencies and ionospheric plasma vertical velocity in January • for the year of low solar activity, • (b) for the year of high solar activity. Maps of allocation of vertical velocity of ionospheric plasma for January, 15 from 0 to 12 UT 4:00 (top to bottom) in the year of low (left) and high (right) solar activity
Ozone observations Farman J.C. Large losses of total ozone in Antarctica reveal seasonal ClOx/NOx Interaction /J.C. Farman, B.D. Gardner, J.D. Shanklin // Nature – 1985. – vol. 315. – P. 207-210. By using variations of ozone content during the ozone hole, it is possible to estimate the role of ozone layer inthe energy transfer between the atmospheric layers
Geomagnetic observatory AIA PROVISIONAL K INDICIES FOR ARGENTINE ISLANDS NOVEMBER 1998 DAY E1 E2 E3 E4 E5 E6 E7 E8 SUM 1 1 1 1 2 1 1 2 2 11 2 2 1 0 1 1 1 3 2 11 3 2 1 0 2 1 2 2 3 13 4 2 0 1 2 2 1 1 2 11 5 2 1 1 2 2 3 3 2 16 6 3 3 4 3 3 2 3 3 24 7 3 2 3 3 4 3 4 3 25 8 5 7 6 4 3 3 4 5 37 9 5 6 6 6 4 3 5 5 40 10 3 2 2 2 1 2 1 1 14 11 1 0 0 2 1 1 2 2 9 12 0 1 2 1 1 1 2 2 10 13 6 4 5 5 4 4 5 5 38 14 5 5 4 5 4 3 4 3 33 FREQUENCIES OF K MAX 0 1 2 3 4 5 6 7 8 9 Missing 6 42 100 57 15 14 5 1 0 0 0 Magnetic anomaly. Century variations of magnetic field
Sporadic E-layers 16 DenseEs Transparence Es High pressure High pressure Low pressure Low pressure December а) b) Difference in probabilities of Es appearance under the high and low surface pressure а) May-August; b) November-February June Daily variations of dense and transparent Es Daily variations of Es appearance: а) all, b) dense,c) transparence
Spread-F effect as a detector of impact of neutral atmosphere on the ionospheric irregularities Dependence of the spread-F appearance on the disturbance level of geomagnetic field а c b d Daily variations of spread-F at the Akademik Vernadsky for January (а), April (b), July (c), and October (d). Seasonal variation of spread-F over Akademik Vernadsky estimated by 13-years sequence of data (1993-2005) Dependence of the spread-F appearance on the disturbance level of geomagnetic field in the different seasons
Daily variations of spread-F dependence on the surface pressure and wind. Difference of conditional probabilities North-east High pressure South-west Winter Low pressure North-east High pressure Summer Low pressure South-west
The role of ozone layer inthe troposphere-to-ionosphere energy transfer
The role of ozone layer inthe troposphere-to-ionosphere energy transfer September 11 – October 5, 1995-2004 TOC < 180 D.U. TOC > 180 D.U.
Modeling. Temperature and wind profiles in frames of NRLMSISE-00 for 65S 65W
Summary • The energy transfer from the troposphere to higher atmospheric layers is effectively provided by propagation of internal atmospheric waves. • Analyzing the processes in the geospace we should take into account the disturbances in low atmosphere, especially in winter time.
Interannual variability RWM - UAS 9996 kHz, 2010 May May June July July August August September September June 73.9, 13.61 73.9, 13.61 72.6, 12.27 72.6, 12.27 79.9, 8.74 79.9, 8.74 79.7, 12.23 79.7, 12.23 81.1, 8.77 81.1, 8.77 2011 2011 CHU - UAS, 07850 kHz 2010 95.7, 14.48 95.8, 14.07 94.3, 14.16 101.8, 11.45 134.5, 19.30 95.7, 14.48 95.8, 14.07 94.3, 14.16 101.8, 11.45 134.5, 19.30
Impact of Es of tropospheric origin on the very-long distant propagation of HF radio signals Surface pressure variations 23-25.06.2010 according to data obtained at UAS meteoobservatory Daily logarithmic spectrograms of signals on RWM-UAS radio line. а) month-averaged daily spectrogram calculated without 24.06.2010, b) Daily for the 24.06.2010. Ionograms over the RWM stationreceived on 23.06.2010, 24.06.2010, and 25.06.2010 03:30 UT Ionograms over UAS received on 23.06.2010, 24.06.2010 , and 25.06.2010 at 03:30 UT