Without question, cycle 24 is
confounding theory and the hard won data from the past few decades. We should be roaring into a classic solar
maximum, yet it appears to be bobbling and now weakening. It could well be that sunspot activity will
now simply die down for a few decades.
It certainly cannot be discounted.
The failure of key indicators of
the next cycle to appear three years ago strongly indicates a long delayed
cycle 25 and suggests a stretching out of the cycles into a long period of quiescence
comparable to the Maunder Minimum. We
may well be mapping this behavior for the first time and it may well be way
more important than any ever imagined.
Maunder did coincide with the
sharp onset of the little ice age, but that could well be a simple coincidence
of overlapping time periods not to be taken as cause and effect. However the slow onset of the cycle 24 does coincide
very well with the disturbed weather conditions we have recently exposed to and
the related weakening of our magnetic shield allowing a greater influx of cosmic
rays leading to increased precipitation.
These are coincidences that I do
not like.
Sun's Fading Spots Signal Big Drop in Solar Activity
by Denise Chow, SPACE.com Staff Writer
Date: 14 June 2011 Time: 03:50 PM ET
A photo of a sunspot taken in May 2010, with Earth shown to scale. The
image has been colorized for aesthetic reasons. This image with 0.1 arcsecond
resolution from the Swedish 1-m Solar Telescope represents the limit of what is
currently possible in terms of spatial resolution.
CREDIT: The
This story was updated at 3:54 p.m. EDT.
Some unusual solar readings, including fading sunspots and weakening
magnetic activity near the poles, could be indications that our sun is
preparing to be less active in the coming years.
The results of three separate studies seem to show that even as the
current sunspot cycle swells
toward the solar maximum, the sun could be heading into a more-dormant
period, with activity during the next 11-year sunspot cycle greatly reduced or
even eliminated.
The results of the new studies were announced today (June 14) at the
annual meeting of the solar physics division of the American Astronomical
Society, which is being held this week at New Mexico State University in Las
Cruces.
"The solar cycle may be going into a hiatus," Frank Hill,
associate director of the National Solar Observatory's Solar Synoptic Network,
said in a news briefing today (June 14).
The studies looked at a missing jet stream in the solar interior,
fading sunspots on the sun's visible surface, and changes in the corona and
near the poles. [Photos:
Sunspots on Earth's Star]
"This is highly unusual and unexpected," Hill said. "But
the fact that three completely different views of the sun point in the same
direction is a powerful indicator that the sunspot cycle may be going into hibernation."
Spots on the sun
Sunspots are temporary patches on the surface of the sun that are caused
by intense magnetic activity. These structures sometimes erupt into energetic
solar storms that send streams of charged particles into space.
Since powerful charged particles from solar storms can occasionally
wreak havoc on Earth's magnetic field by knocking out power grids or disrupting
satellites in orbit, a calmer solar cycle could have its advantages.
Astronomers study mysterious sunspots because their number and
frequency act as indicators of the sun's activity, which ebbs and flows in an
11-year cycle. Typically, a cycle takes roughly 5.5 years to move from a solar
minimum, when there are few sunspots, to the solar maximum, during which
sunspot activity is amplified.
Currently, the sun is in the midst of the period designated as Cycle 24
and is ramping up toward the cycle's period of maximum activity. However, the
recent findings indicate that the activity in the next 11-year
solar cycle, Cycle 25, could be greatly reduced. In fact, some scientists
are questioning whether this drop in activity could lead to a second Maunder
Minimum, which was a 70-year period from 1645 to 1715 when the sun showed
virtually no sunspots. [Video:
Rivers of Fire Inflame Sunspots]
Hill is the lead author of one of the studies that used data from the
Global Oscillation Network Group to look at characteristics of the solar
interior. (The group includes six observing stations around the world.) The
astronomers examined an east-west zonal wind flow inside the sun, called
torsional oscillation. The latitude of this jet stream matches the new sunspot
formation in each cycle, and models successfully predicted the late onset of
the current Cycle 24.
"We expected to see the start of the zonal flow for Cycle 25 by
now, but we see no sign of it," Hill said. "The flow for Cycle 25
should have appeared in 2008 or 2009. This leads us to believe that the next
cycle will be very much delayed, with a minimum longer than the one we just went
through."
Hill estimated that the start of Cycle 25 could be delayed to 2021
or 2022 and will be very weak, if it even happens at all.
The sun's magnetic field
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
.
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."
You can follow SPACE.com staff writer Denise Chow on Twitter @denisechow. Follow
SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.
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