Solar Cycle Science Discover the Sun!

Check out our new Solar Cycle Science Forum!!!!

Discover the Predictions!

This page features our predictions and forecasts for the Sun. Currently, we have Solar Cycle predictions for Solar Cycle 24 (cycle amplitude and F10.7 flux) and Solar Cycle 25 (cycle amplitude). We also show our predictions for the evolution of the Sun's polar magnetic fields for the remainder of Solar Cycle 24, which were used to predict the amplitude of Cycle 25.

Discover the Cycle 24 Predictions!

Predicting the behavior of a sunspot cycle is fairly reliable once the cycle is well underway. Former MSFC Solar Physics Branch members Wilson, Hathaway, and Reichmann have studied the sunspot record for characteristic behavior that might help in predicting future sunspot activity. Among the most reliable techniques are those that use the measurements of changes in the Earth's magnetic field at, and before, sunspot minimum, e.g. "geomagnetic precursors". This prediction was created using a combination of geomagnetic precursors techniques. Details can be found here.

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.

Solar Cycle 24 Prediction. A larger version of this image can be found here. A basic plot (without the image of the Sun) can be found here in gif format and here in pdf format. The data used to make all of these is in this text file.
Another indicator of the level of solar activity is the flux of radio emission from the Sun at a wavelength of 10.7 cm (2.8 GHz frequency). This flux has been measured daily since 1947. It is an important indicator of solar activity because it tends to follow the changes in the solar ultraviolet that influence the Earth's upper atmosphere and ionosphere. Many models of the upper atmosphere use the 10.7 cm flux (F10.7) as input to determine atmospheric densities and satellite drag. F10.7 has been shown to follow the sunspot number quite closely and similar prediction techniques can be used. Our predictions for F10.7 are available in a text file, as a Jpeg image, and as a pdf-file. Current values for F10.7 can be found at:

Solar Cycle 24 F10.7 Flux Prediction. A pdf of this plot can be found here. The data used to make these plots are located in this text file.

Discover the Cycle 24 Polar Field Predictions!

We have used our AFT code to predict the amplitude and hemispheric asymmetry of the Sun’s polar magnetic fields at the start of 2020, approximately the next cycle minimum. (Recall that observations have shown that the strength of the polar fields is a good indicator of the strength of the next cycle.) While we do not know the details of the active region sources and transport flows that will occur between now and then, we use knowledgeable estimates, along with their known variability, to produce a series of 32 realizations for the evolution of the Sun’s surface magnetic field from the end of January 2016 to the start of January 2020.

Solar Cycle 24 Polar Field Predictions. The left plot shows 16 predictions with 8 variations in the convective flow pattern and 2 variation in the meridional flow profile. The right plot shows 16 predictions with 8 variations in the Joy's Law tilt and 2 variation in the meridional flow profile. All 32 realizations predict the polar fields for the coming minumun will be similar in strength (or slightly weaker) than the polar fields that were seen during the last solar minimum.
More information about these predictions can be found in this paper.

Discover the Cycle 25 Predictions!

We find that the average strength of the polar fields near the end of Cycle 24 will be similar to (or slightly weaker) that measured near the end of Cycle 23, indicating that Cycle 25 will be similar in strength (or slightly weaker) to the current cycle. After four years of simulation the variability across our ensemble indicates that the accumulated uncertainty is on the order of about 15%. This uncertainty arises from stochastic variations in the convective motion details, the active region tilt, and changes in the meridional flow. In addition, small cycles (like cycle 24) are typically preceded by long extended minima, and so we expect a similar long extended minimum before Cycle 25.

Solar Cycle 25 Prediction. We find that the polar fields indicate that Cycle 25 will be similar in size to (or slightly smaller than) the current small cycle, Cycle 24. Small cycles, like Cycle 24, start late and leave behind long cycles with deep extended minima. Therefor, we expect a similar deep, extended minimum for the Cycle 24/25 minimum in 2020.

More information about this prediction can be found in this paper.