Электродинамические процессы в высоких широтах: материалы междунарордного симпозиума «Полярные геомагнитные явления», 25-31 мая 1986 г., Суздаль, СССР / Междунар. геодез. и геофиз. союз, Междунар. ассоц. геомагнетизма и аэрономии ; Акад. наук СССР, Кол. фил. им. С. М. Кирова, Поляр. геофиз. ин-т ; [редкол.: О. М. Распопов (отв. ред.). и др.]. - Апатиты : Кольский филиал АН СССР, 1988.

Figure 1. Relationship of Svalbard an d H eiss Island stations to the auroral oval (Q » 4) (cf.Feldstein and Starkov,1967) a n d the sunlit earth in D e c e mber at magnetic n o o n ( ~ 09 UT). The No r t h A merican observing chains are indicated to show the possibility of simultaneous observations of devel oping substorms on the nightside an d the mi d d a y aurora f r o m Svalbard and Heiss Island. observations at magnetic mi d d a y (cf. F i g . 1), the cusp aurora lias received m a rked l y less attention than the night-time aurora. The only site in the n o rthe r n hemisphere w h i c h satisfy the above requirements f or optical observ ations of the mi d d a y auroras are Svalbard (Norway) a n d Franz Josefs Land (including He i s s Island) (USSR). I n this study the data sets from bo t h places are presented. One set is obtained f r o m Svalbard by N o r wegian a n d A merican groups (cf.Sections 2 and 3). The other set consists of observations b y Soviet scientists from Heiss Island an d Svalbard (of. Sections 4 and 5). The topic of b o t h data sets is the dynamics of dayside polar cusp aurora i n relation to IMF variations and m a g n e t oapheriс substorms. As set N o 1 is focused on individual cases only, the Soviet contribution also includes a statistical analysis. Different possible influences on the location and dynamics of the day- side polar cusp aurora have be e n extensively discussed in the past (e.g. re v i e w b y B u r c h , 1979} S h e p h e r d , 1979). H owever no general agreement exists on the relative importance of the IMF B a component and internal magnetospheric processes like substorms an d storms (ring current). A l l-sky camera observa tions of day- and nightside auroral dynamics in relation to substorm activi ty were reported by Feldstein and Starkov (1967), V orobjev et a l , (1975,19761 117