Measures of Solar Activity

Polar Solar Magnetic Field

The solar polar field is plotted to the right. The observations were made at Wilcox Solar Observatory, Stanford.

Heavy solid line represents smoothed average. Red solid is North. Dashed blue is -South.

The North pole has now changed its polarity from + to -. The South pole has also changed its polarity from - to +.

This is what is expected to happen around the solar maximum.

The amplitude of the polar field during solar cycle minimum has been used to predict the amplitude of the coming solar maximum.