Solar Cycle Prediction

Author: Dr. David H. Hathaway

The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number V2.0 maximum of about 101 in late 2013. The smoothed sunspot number V2.0 reached a peak of 116.4 in April 2014. This will probably become the official maximum. This second peak surpassed the level of the first peak (98.3 in March 2012). Many cycles are double peaked but this is the first in which the second peak in sunspot number was larger than the first. We are currently over seven years into Cycle 24. The current predicted and observed size makes this the smallest sunspot cycle since Cycle 14, which had a maximum smoothed sunspot number V2.0 of 107.2 in February of 1906.
Predicting the behavior of a sunspot cycle is fairly reliable once the cycle is well underway (about 3 years after the minimum in sunspot number occurs [see Hathaway, Wilson, and Reichmann Solar Physics; 151, 177 (1994)]). Prior to that time the predictions are less reliable but nonetheless equally as important. Planning for satellite orbits and space missions often require knowledge of solar activity levels years in advance….READ MORE