Polar coronal holes and solar cycles

✍ Scribed by Paul A. Simon

• Publisher: Springer
• Year: 1979
• Tongue: English
• Weight: 534 KB
• Volume: 63
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00174544

✦ Synopsis

The relationship between the geomagnetic activity of the three years preceding a sunspot minimum and the peak of the next sunspot maximum confirms the polar origin of the solar wind during one part of the solar cycle. Pointing out that the polar holes have a very small size or disappear at the time of the polar field reversal, we suggest a low latitude origin of the solar wind at sunspot maximum and we describe the cycle variation of solar wind and geomagnetic activity. In addition we note a close relationship between the maximum level of the geomagnetic activity reached few years before a solar minimum and its level at the next sunspot maximum. Studying separately the effects of both the low latitude holes and the solar activity, we point out the possibility of predicting both the level of geomagnetic activity and the sunspot number at the next sunspot maximum. As a conclusion we specify the different categories of phenomena contributing to a solar cycle.