VARIATION IN NORTH-SOUTH ASYMMETRY OF SUN SPOT AREA

The existence of the North-South asymmetry of the solar activity is widely accepted even though the phenomenon is not yet satisfactorily understood. We have studied the temporal variations in the North-South asymmetry of the sunspot area during the period from May in 1874 to April in 2007. The combined data have been examined for periodicity in the solar activity North-South asymmetry. We have found that (i) solar northern and southern hemispheres show an asymmetric behavior, in terms of a sunspot area, (ii) sunspot areas in northern and southern hemispheres show clearly the 11 year periodicity when they were analyzed separately, as they do when analyzed together, (iii) in addition to the general 11 year periodicity in both northern and southern hemisphere solar activities, there are also noticeable shorter periodicities other than the 11 year periodicity in the asymmetry in North-South activity. Finally, we conclude by pointing out the importance of studying the North-South asymmetry of the solar activity.