June 14, 2011
BUT I JUST KNOW WE'RE THE ONES CHANGING THE CLIMATE!:
Sun's Fading Spots Signal Big Drop in Solar Activity (Denise Chow, 6/14/11, SPACE.com)
In the second study, researchers tracked a long-term weakening trend in the strength of sunspots, and predict that by the next solar cycle, magnetic fields erupting on the sun will be so weak that few, if any, sunspots will be formed.
With more than 13 years of sunspot data collected at the McMath-Pierce Telescope at Kitt Peak in Arizona, Matt Penn and William Livingston observed that the average magnetic field strength declined significantly during Cycle 23 and now into Cycle 24. Consequently, sunspot temperatures have risen, they observed.
If the trend continues, the sun's magnetic field strength will drop below a certain threshold and sunspots will largely disappear; the field no longer will be strong enough to overcome such convective forces on the solar surface.
In a separate study, Richard Altrock, manager of the Air Force's coronal research program at NSO's facility in New Mexico, examined the sun's corona and observed a slowdown of the magnetic activity's usual "rush to the poles."
"A key thing to understand is that those wonderful, delicate coronal features are actually powerful, robust magnetic structures rooted in the interior of the sun," Altrock said. "Changes we see in the corona reflect changes deep inside the sun."
Altrock sifted through 40 years of observations from NSO's 16-inch (40 centimeters) coronagraphic telescope.
New solar activity typically emerges at a latitude of about 70 degrees at the start of the solar cycle, then moves toward the equator. The new magnetic field simultaneously pushes remnants of the past cycle as far as 85 degrees toward the poles. The current cycle, however, is showing some different behavior.
"Cycle 24 started out late and slow and may not be strong enough to create a rush to the poles, indicating we'll see a very weak solar maximum in 2013, if at all," Altrock said. "If the rush to the poles fails to complete, this creates a tremendous dilemma for the theorists, as it would mean that Cycle 23's magnetic field will not completely disappear from the polar regions. … No one knows what the sun will do in that case."
If the models prove accurate and the trends continue, the implications could be far-reaching.
"If we are right, this could be the last solar maximum we'll see for a few decades," Hill said. "That would affect everything from space exploration to Earth's climate."
Posted by oj at June 14, 2011 5:33 PM