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Title: Predict the amplitude and timing of solar cycle 26
Plain: Space weather depends on how active the next solar cycle will be, and past forecasts have often missed.
Precise: Predict the 13-month smoothed maximum sunspot number (SILSO version 2) of cycle 26 and its date, using polar magnetic field precursors at the cycle 25/26 minimum, surface flux transport models and dynamo data assimilation. Answer: a forecast with uncertainty registered before the minimum and scored against the observed maximum.
Settled by: Comparison of forecasts registered before the cycle 25/26 minimum with the observed cycle 26 maximum.
Kind: well-posed
Answer type: value
References: (empty)
Literature status: open
Status note: 2024: cycle 25 reached its maximum in October 2024 with a smoothed sunspot number of about 161, above the 2019 NOAA-NASA panel forecast of 115.
Posed since: (empty)