Physics of auroral phenomena : proceedings of the 36th Annual seminar, Apatity, 26 February – 01 March, 2013 / [ed. board: A. G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2013. - 215 с. : ил., табл.

GPS/TECfluctuations at high latitude during geomagnetic storm o f 11 October 2010 12 UT. It is necessary to note that the strong TEC fluctuations were observed on different azimuth directions over stations. For both stations maximal intensity took place simultaneously, but in some cases fluctuations intensity peaks was observed over subauroral station later than over auroral station. 5. Latitudinal and temporal occurrence of TEC fluctuations As a measure of the fluctuation activity the Rate of TEC Index (ROTI) based on standard deviation o f ROT was used [Pi et al., 2009]. The ROTI was estimated on 10-minute interval. r o t i = ^I( r o t 2) - ( r o t ) 2 The occurrence of TEC fluctuations essentially depend on geomagnetic latitude. Latitudinal behavior of TEC it was analyzed using ROTI measurements over stations located at different latitudes. To obtain spatial and temporal distribution of the TEC fluctuations it was formed images ROTI in Corrected Geomagnetic Latitude (CGL) and Magnetic Local Time (MLT) coordinates (Fig. 4). Stations were chosen due to their location relative to auroral oval. Over subauroral NNVN station during quiet day the low fluctuations were observed at evening time that indicates that the station locates out side auroral oval. During driven phase of storm strong the fluctuations were observed after 12 MLT when Bz is persistently kept negative. The TEC fluctuations development next days were occurred according to development substorm activity on recovery phase storm and strong fluctuations were observed near local midnight. RINK (71.739/77.74, -50.99/46.14) 2010 October, 11 12 t- O 0£ KUAQ (68.45/71.45, -33.05/61.23) 2010 October, 11 12 _ 0.3 I 0.2 - 0.0 I 0.1 0.0 NNVN (61.47/66.59,-44.90/44.10) NNVN (61.47/66.59,-44.90/44.10) 2010 October, 10 2010 October, 11 0.0 0 NNVN (61.47/66.59, -44.90/44.10) 2010 October, 12 Fig. 4 The occurrence of TEC fluctuations at different latitudes. At station KUAQ the low TEC fluctuations were observed during all day. The fluctuations intensity increased during storms. Generally the development of fluctuations was similar to subauroral NNVN station but intensive fluctuations were detected during more continuous time. Increase of TEC fluctuations were detected at the same UT time, similar NNVN stations. On the Fig. 4 the occurrence TEC fluctuations at RINK station also are presented. This station on dayside corresponds to the cusp region. Over this station the behavior o f TEC fluctuations rather differ ^ o . o о KUAQ (68.45/71.45, -33.05/61.23) 2010 October, 10 I 0.3 0.2 - h- o : 0.1 * RINK (71.739/77.74, -50.99/46.14) 2010 October, 10 1 0.2 — ( - О 10.1* 10.2 — K o 10.1“ 00 RINK (71.739/77.74, -50.99/46.14) 2010 October, 12 I 0.3 0.2 - ь 18K4fSH - 1 I. 1 о o.i K L—— 0.0 0 KUAQ (68.45/71.45, -33.05/61.23) 2010 October, 12 I 0.3 ! 0.2 - « н а кат i - и . l a &jB ■ о 168