Drift of Polar Prominences in Solar Cycles 13–24

Аннотация

A comparative analysis of the drift velocity of high-latitude prominences to the poles in solar cycles 13–24 is carried out. Data on the positions of prominences on weather maps from Wolfer (1887–1899) and (1904–1915) are used for the analysis. The data from digitized photographic plates with solar prominences obtained in the CaIIK line of the Kodaikanal Solar Observatory (India) for 1907–1956 are also used. These data are supplemented with daily observations of the prominences at Kislovodsk Mountain Astronomical Station (1957–2018). The dependence of the drift velocity of polar-crown prominences on the solar cycle strength is different for the northern and southern hemispheres. The drift velocity tends to decrease with increasing solar activity. This may be due to the fact that a strong large-scale magnetic field is observed at high latitudes before strong solar cycles. Its displacement rate, which is traced by the drift of polar prominences, then slows with the development of a cycle with an increasing polar field.