Enjoy it while it lasts

The Sun Blog » Space Climate Symposium, Day 2 - Irradiance and Grand Minima

The Sun appears to spend about 1/6 of the time in a grand minimum state, and 1/10 in a grand maximum. What causes such states is unknown, and does not appear to happen in any predictable way. As noted in yesterday’s post, the solar cycle is at some level unpredictable, so this is not surprising.

Results by Jose Abreu (whose paper I have discussed elsewhere) suggest that the present grand maximum is going to end soon, within about 15 years. Whether the Sun will go into a grand minimum or merely a period of weaker cycles is not known. However, the extended nature of the present solar minimum points toward a weak Cycle 24, and there is at least one prediction of a very weak Cycle 25. Thus, significant evidence points toward a period of weaker solar activity or possibly an upcoming grand minimum. Could the Sun fool us? Of course, but we have to go with what the preponderance of the data says, and for now, weak activity is it. [Via Russ Steele]