Авроральные явления - 72 : материалы наблюдений Полярного геофизического института за 1972 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, 1975 (обл. 1976).

5 level of activity continues during several days gradually decreasing. On Loparskaja and Lovozero magnetograma the increase of activity desplaya only at oertain hours i in the f o r m of positive geomagnetic bays in tha evening, at night and early morning- in the form of negative bays. The magnetic storm usually appears as line of eubstorms overlapping each other. During the days after storm the distance between eubstorms grows,its activity becomes weak and finally the substorms are recorded as separate isolated phenomena. AE or A L indexes behaviour gives the chance to estimate the appearance and intensity of the planetary substorm. If this planetary substorm (increasing AE) takes place at late morning or at day hours the planetary substorm at Loparskaya is marked b y absorption increasing. This fact gives the occasion to think that we can obtain any information about mognetoapheric substorm appearance fr o m one observatory data even at those hours when the substorm does not influence the magnetic field variation. The seasonal variation of activity for 1972 is given at i'ig.2 (a - for geomag- netic activity, b - ionospheric activity,according to the calendar of Fig.1, с-auro- ras, d - planetary AL-index, e - sunspot numbers). It is interesting to note the un usual weakness of equinoctial maximum in rH behaviour in 1972, The seasonal changes of geomagnetic activity are small. The increasing of activity in August is connected with unusually severe storm. It із evident from Fig.2b that ionospheric activity decreased in summer and is maximum in winter. Planetary AL-index and sunspot number reduces tothe end of the year. A comparably hig h intensity 6300 X emission at the beginning of the year can be connected with the usually high fluxes of soft particles precipitated into F-region. Fig.3 presents the dependence of ionospheric activity (in accordance with Fig.1) on sunspot numbers (W) and the comparison of local hourly range r^ wi t h the planeta r y AL-index, It is evident that the correlation of ionospheric disturbances with the sunspot numbers are almost absent or even negative. The positive r^ - A L correlation is evident,though the cloud of values is rather widespread, Fig,4 shows a daily variation of different forms of activity for different sea sons of 1972 . The months are combined in the following wa y 1 winter - January,Novem ber .December} spring - February,March ,Ap.ril$aummer»- May,June,July}autumn - August, September.October. Ionospheric activity (Fig.4) ia maximum at night and minimum at noon. In winter months the maximum «irises earlier than in summer. The behaviour of most auroral emissions (Fig.4b) is characterized b y three maxima i the main and wide - near the midnight and two additional - in the morning and in the evening. Similar to ionospheric activity magnetic activity із characterized b y wide night maximum,the highest - in spring and autumn and the lowest - in summer. The additio nal minimum of magnetic activity appears in evening hours in summer, Inthe Russian text the description of activity behaviour during different months of the year are given. One can see how typical pecularities mentioned in the above description desplay in certain disturbances occurred in 1972.