Physics of auroral phenomena : proceedings of the 33rd Annual seminar, Apatity, 02 - 05 March, 2010 / [ed.: A.G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2011. - 206 с. : ил.

Fig. 4. a) TEC fluctuations azimuth distribution at Antardtic stations at ~ 18 UT; b) Auroral oval over Antarctica at Q = 6. Fig. 5. a) Normalized vector azimuth diagram o f the number of ionospheric irregularities (TEC patches) occurred inside 30° sectors (the sector radius is proportional to the number of TEC patches), b) The diagram of the areas covered by the auroral oval in the 30° sector ( the sector radius is proportional to the area square). Conclusions The GPS measurements of northern and southern hemispheres were used to study storm-time development of TEC fluctuations at conjugate area in polar cap, auroral and subauroral ionosphere. During storms the intensity of irregularities essentially increases and strong TEC fluctuations can be registered at subauroral ionosphere. Maximal activity of TEC fluctuations took place when IMF Bz component was large negative. Storm-time development of TEC fluctuations caused by ionospheric irregularities was controlled by UT. At polar cap stations TEC fluctuations more expressed at southern (winter) hemisphere. Over auroral and subauroral stations the difference of TEC fluctuations occurrence was less expressed. Auroral oval presentation as azimuth vector diagrams could be used for a study of GPS signals propagation.The GPS technique can be effectively use for probing of the oval irregularities of high-latitude ionosphere near real time and auroral technique can be used for control o f GPS signal. A cknow ledgem en ts. The authors thanks to O.Antonenko for preparation work and to the Research Council of Norway through the project named: Norwegian and Russian Upper Atmosphere Co-operation on Svalbard part 2 #196173/S30 (NORUSCA2), the Nordic Council of Ministers grant number i A09161 and the Russian Fund of Basic Research grant 10-05-98800-r-sever_a for the support of this study. References Aarons, J , Global positioning system phase fluctuations at auroral latitudes, J. Geophys. Res., 102 (A8), 17219- 17231, 1997. Aarons, J , Lin, B , Mendillo, M , Liou K , Codrescu M , 2000, GPS phase fluctuations and ultraviolet images from the Polar satellite, Journal Geophysical Research., 105, 5201-5213. Afraymovich E .I, Perevalova N .P , 2006, GPS-monitoring of the Earth's upper atmosphere, Irkutsk: SC RRS SB RAMS, 480 p. Feldstein,Y.I, Starkov G.V. and Zverev V .L , 1974, Conjugacy of auroral oval. Proceedings o f Antarctic review meeting, Tokyo, NIPR, pp.29-37. Shagimuratov I , Efishov I , Ruzhin Yu, Tepenitsyna N , 2006, Storm-time occurrence o f TEC fluctuations associated with polar patches using GPS measurements. In Physics o f Auroral Phenomena, Proceedings of XXIX Annual Seminar, Apatity, Kola Science Centre RAS, pp. 61-64. Shagimuratov, I.I, I.I. Ephishov, N.Yu. and Tepenitsyna, Similarities and Differences o f storm time occurrence of GPS phase fluctuations at northern and southern hemispheres, In Proceeding EUCap 2009. Zverev V .L , Starkov G.V. 1975. Synoptic maps of the auroral oval in the South Hemisphere. In Antarctic, 14, Nauka, Moscow, pp. 5-33 (in Russian). 154 a 12 06 У. Shagimuratov at a l b b 12 06 01