Аскаплоты советских станций за 1982 год : (оперативно-информационный материал) / Акад. наук СССР, Кол. фил. им. С. М. Кирова, Поляр. геофиз. ин-т. – Апатиты : Кольский филиал АН СССР, 1989.

го Methods of ascaplotting. Information about aurorae for every station according to /1,2/ is encoded in 5 lines divided by vertical lines. One vertical dividing corresponds to a half-an-hour interval centered to the beginning and the middle of each hour (UT). The local geomagnetic midnight is marked by a circle under the ascaplot. Three upper lines show aurorae location in the sky. The upper blackened line demonstrates that in a given half-an-hour interval aurorae were observed within the scale of zenith angles from 60° to 80° N. The second blackened line corresponds to aurorae in the zenith (from 60° N to 60° S) and the third one shows aurorae in the south (from 60° to 80° S). Occurence of auroras in the corresponding part of the sky was marked when an aurora was observed during a single minute in a given time interval. The auroral location was defined by its bottom edge. Suppose that the height of the lower edge is equal to 100 km then we get that all three zenith angle intervals have approximately sufficient extent along the meridian corresponding to 3 degrees of latitude. Thus, ascaplots give inform ation on spatial distribution of aurora in 9-degree-latitude range with its centre in the zenith of the station. It should be taken into account that the sensitivity of all-sky cameras is maximum for the zenith and it diminishes when the zenith angle increases, i.e. to the frame edge. The presence of stars on the films makes it possible to judge on meteo rological conditions in every latitude interval. According to /1,2/ the dot in the middle of the square shows weak cloudiness or cloudiness with rents in the given part of the sky and in the given time-interval. The vertical line denotes complete cloudiness. The tick inside the square of the third line points to a bad quality of the ascafilm caused by some technical reasons (inaccurate focusing, poor quality of development, etc.). TJie horizontal line denotes that no observations were carried out. To mark moon lightning which sufficiently reduces the quality of ascafilms we used an additional designation, i.e. the horizontal line over the ascaplot. Two bottom lines of squares carry the information about auroral activity. Blackening of the very bottom line means that 2 ball aurora was observed. Blackening of the two bottom lines refers to 3 ball auroral activity. It should be noted that the activity in ascaplots does not entirely coincide with brightness of forms. The ball of activity also includes such parameters as the type of the form and its life-time within the given half-an-hour interval. Since the compresion of the angle range for the north and the south does not permit similar determinations of peculiarities of auroral forms, the auroral activity in ascaplots was estimated only for the zenith region. The series of auroral activity, which was offered in /7/, characteriz ing the connection between the substorm phase and substorm intensity on one hand, and the type of the form on the other, was taken as a basis. The table for estimating the activity is given in Figure 1. Here the balls of activity are marked at the bottom, horizontal lines denote the types of the forms (corresponding to the international classification) as well as brightness of forms (W - weak, M - mean, В - bright). Two circles denote duration of observations, the left circle means that the observation period was more than 15 minutes shorter than that denoted by the right circle. The indices by which the balls of activity are calculated are given at the top of the table. Indices 1-3 correspond to the first ball, whereas indices 4-6 and