Авроральные явления - 75 : материалы наблюдений Полярного геофизического института за 1975 г. / Акад. наук СССР, Кол. фил. им. С. М. Кирова, Поляр. геофиз. ин-т ; [редкол.: Б. Е. Брюнелли (отв. ред.) и др.]. - Апатиты : Кольский филиал АН СССР, 1978.

5 changes are modulated by duirnai variation. ТПе moments or activity increasing are formed tne reccurent sequences. The sequences of 19/5 are listed on Table at page ^0 and included in .trigs 4 and 5» On both figures days ax>e ax'ranged according to Bartel' Solar rotation and the sequences are compared with the interplanetary sector structure and daily mean equatorial Dst. It is seen that almost all noticable changes of Dst are connected with listed sequences, but the efficiency of sequences is changed during the year. As it Will be seen from the following description all or almost all disturbances of the year can be connected with one of the five reccurent sequences (A j, А, В, С end D). In the first half of the year four of them are connected with the changes of IMF sector structure; D-sequence marks the end of the main negative sector and transition to additional positive. The transition to additional negative sector is marked by Aj-sequence. A and С sequence are connected with the start and the end of the шаід positive sector. Disturbances connected with + and - of IMP transitions are as a rule more intense tnan in reverse case. The highest level of activity is corresponded to C-sequence and main negative IMF sector. At the second naif of the year the character of connection between IMF and geomagnetic activity io changed! the more active periods become connected witn positive sector and the more clear activity increasings are accompanied to the - to + or IMF transitions. In accordance with increased activity -of positive sector B-sequence being weak in the beginning q f the year and existing inside main + sector Ьесоиез the most active in the second half of the year. The existence of the above mentioned sequences is improved by the activity development during each Sun's rotation. Од the Bot 1934 geomagnetic disturbances and increasings or ionospheric abgorption at 3.1, 8.1 (magnetic storm with SSC 23-22UT 07,1) and 13.1 are connected With A, Вand O-sequences, wnich o o n t m u e similar sequences of 1974 /6/. D-sequence is not; developed during this and following rotations. During Rot I9j5 A j , A and В sequences display in the disturbances at 27.1, 3 1 .1 and 4 . H j active period beginning at 9«IX ia connected with G-eequence. On Rot 1936 Aj, A and B-aequences are accompanied by the disturbances at 2 3 » H j 2b.II and 5 . 1 H respectively, SC- magnetic storm (9,111) and long active period roliowed it are connected with C- sequence. Small separate disturbance at 22.Ill may be considered as a first mark ОЙ D-sequence. The i n c r e a s i n g of activity at 24*IiI and 27.i n are connected with A-j and A-sequences Of Rot 19 *7. The В-disturbance is пот; seen, O-discurbance begins at 4 . 1 V as a rather moderate one, its ontensity increases and reaches maximum near 9-10,IV. IMJ ;1 during Hot l9j7 is not such stable as during previous rotations, the main negative sector starts before C-sequence, the increasing of activity at 9-Ю.ГѴ is coincided with appearance of positive IMif. On the Rot 193b the first period of increased activity starts at 20.IV (A^-sequence) and include А-sequence (presumable at 2 3 .IV). The period is not accompanied by change of IMF sign, fcne additional negative sector appeared to be absent. О-sequence, as on previous rotations gives rise a gradual increase of activity at 2.V with maximum near >.V. T h e level 01 activity is not so nigh and long as at previous rotations, disturbances cease inside negative sector. Moderate disturbance,(but still more intense than previous one.) arises in connection witn D-sequence ( 1 3 .V). A^-sequence 01 Kot -i9-)9 is developed as SC-magnetic storm (SSC at О 3 .О 8 UT 16.V). А-sequence is marked by double substorm (19»V), B-sequence - as a well developed disturbance (25»V)« With G-sequence is i connected long, but moderate disturbed period beginning at 1 .VI, The activity again is ceased inside the negative sector. With Drsequence may be connected moderate substora, though the disturbance arises some days early than it is typical for D -