Using the analysis of solar patrol H-alpha films and other solar data, a detailed coordination of geomagnetic activity phenomena with foregoing solar situations in the immediate vicinity of the center of the solar disk was carried out for 104 cases during February, March and April 1972. In the period considered the increases of geomagnetic activity depend mostly on the presence of variable filaments, whereas the cases of geomagnetic calm correspond to the presence of sunspot groups or flocculae without sunspots and are never associated with variable filaments or with the undisturbed area of the disk.
Electromagnetic Field of the Earth
- Pub Date:
- Solar Activity Effects;
- Solar Terrestrial Interactions;
- H Alpha Line;
- Solar Corona;
- Solar Flares;