It was announced at the recent annual meeting of the Solar Physics Division of the American Astronomical Society (AAS/SPD) at New Mexico State University that the next 11-year solar sunspot cycle, Cycle 25, will be greatly reduced or will not occur at all. Magnetic fields erupting from the sun will be so weak that few if any sunspots will form. The current sunspot cycle, Cycle 24, started out late and slow and will likely produce a very weak solar maximum in 2013.

This report from the National Solar Observatory (NSO) and the Air Force Research Laboratory at Kitt Peak in Arizona indicates that the familiar sunspot cycle may be shutting down for a while, causing global cooling.

Migration of Internal Current Flows

Frank Hill, associate director of the NSO’s Solar Synoptic Network, was the lead author on one of three papers presented at the conference on sunspot cycles.1 Using data from six observing stations in the Global Oscillation Network Group (GONG), his team translated pulsations caused by sound waves reverberating in the sun using models of its internal structure.

They found that east-west zonal currents inside the sun, called the torsional oscillation, migrate toward the equator and match new sunspot formations for each cycle. They successfully predicted the late onset of the current Cycle 24. Hill said in an AAS/SPD press release:

We expected to see the start of the zonal flow for Cycle 25 by now, but we saw no sign of it. This indicates that its start may be delayed to 2021 or 2022, or may not happen at all.2

Weak Sunspots

In a second paper, William Livingston, Matt Penn, and L. Svalgard saw a long-term weakening trend in the strength of sunspots, and predicted that by Cycle 25 magnetic fields erupting on the sun will be so weak that few if any sunspots will be formed.3 Sunspots are formed when intense magnetic flux tubes erupt from the interior and keep cooled gas from circulating back to the interior. For typical sunspots, this magnetism has a strength of 2,500 to 3,500 gauss (earth’s magnetic field is less than 1 gauss at the surface). The field must reach at least 1,500 gauss to form a dark spot….

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