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On the Origin of Solar and Stellar Magnetic Fields
There is recent evidence that the solar magnetic cycle has been interrupted.
This is a link to Livingston and Penn’s paper that notes the magnetic field strength of newly formed sunspots is decreasingly linearly. Specifically, why the magnetic field strength of newly formed sunspots is decreasing is not known. There is in the paleoclimatic record evidence of unexplained cyclic abrupt climate changes (Bond events and Heinrich events) that correlate with abrupt cosmogenic isotope changes. The cosmogenic isotope changes are known to be caused by solar magnetic cycle changes and by geomagnetic field changes. It is time for the next 1470 year Bond climate change event and the next 8,000 to 10,000 year Heinrich event (It appears the Heinrich event is a very, very, strong Bond event). Assuming the sun was the cause of the past Bond and Heinrich events, the solar magnetic cycle from time to time is interrupted. Based on an assume mechanism that explains what is observed in the paleo record, the restart of the solar magnetic cycle is what causes the Bond and Heinrich events.
I am not interesting in discussing the fundamental mechanisms (solar, geomagnetic, and atmospheric) how a solar magnetic cycle interruption could physically cause what is observed unless there is definitive evidence that the solar magnetic cycle has been interrupted in an anomalous manner as opposed to a normal cyclic slowdown of the solar magnetic cycle. There may be a number of months or years before there is evidence to resolve this question.
I will however start a separate thread to discuss structured astronomical anomalies which appear to point to a possible theoretical explanation. (i.e. I have been specifically looking for astronomical evidence to construct and support a strawman mechanism. What I found is interesting regardless of whether it does or does not support a new mechanism for the generation of astronomical magnetic fields.)
http://arxiv.org/abs/1009.0784
There is a suite of recent astronomical and solar observational evidence that supports the assertion that the assumed fundamental mechanisms by which magnetic fields are created in stellar and very large astronomical bodies is incorrect. The seismological evidence that the solar convection is 20 to 100 times less than theoretically assumed which makes the assumed mechanism to generate the solar magnetic field not possible is only one of many.
http://www.nyu.edu/about/news-publi...-create-mri-of-the-suns-interior-motions.html
http://arxiv.org/pdf/1206.3173.pdf
There is recent evidence that the solar magnetic cycle has been interrupted.
This is a link to Livingston and Penn’s paper that notes the magnetic field strength of newly formed sunspots is decreasingly linearly. Specifically, why the magnetic field strength of newly formed sunspots is decreasing is not known. There is in the paleoclimatic record evidence of unexplained cyclic abrupt climate changes (Bond events and Heinrich events) that correlate with abrupt cosmogenic isotope changes. The cosmogenic isotope changes are known to be caused by solar magnetic cycle changes and by geomagnetic field changes. It is time for the next 1470 year Bond climate change event and the next 8,000 to 10,000 year Heinrich event (It appears the Heinrich event is a very, very, strong Bond event). Assuming the sun was the cause of the past Bond and Heinrich events, the solar magnetic cycle from time to time is interrupted. Based on an assume mechanism that explains what is observed in the paleo record, the restart of the solar magnetic cycle is what causes the Bond and Heinrich events.
I am not interesting in discussing the fundamental mechanisms (solar, geomagnetic, and atmospheric) how a solar magnetic cycle interruption could physically cause what is observed unless there is definitive evidence that the solar magnetic cycle has been interrupted in an anomalous manner as opposed to a normal cyclic slowdown of the solar magnetic cycle. There may be a number of months or years before there is evidence to resolve this question.
I will however start a separate thread to discuss structured astronomical anomalies which appear to point to a possible theoretical explanation. (i.e. I have been specifically looking for astronomical evidence to construct and support a strawman mechanism. What I found is interesting regardless of whether it does or does not support a new mechanism for the generation of astronomical magnetic fields.)
http://arxiv.org/abs/1009.0784
Long-term Evolution of Sunspot Magnetic Fields
Independent of the normal solar cycle, a decrease in the sunspot magnetic field strength has been observed using the Zeeman-split 1564.8nm Fe I spectral line at the NSO Kitt Peak McMath-Pierce telescope. Corresponding changes in sunspot brightness and the strength of molecular absorption lines were also seen. This trend was seen to continue in observations of the first sunspots of the new solar Cycle 24, and extrapolating a linear fit to this trend would lead to only half the number of spots in Cycle 24 compared to Cycle 23, and imply virtually no sunspots in Cycle 25...
We reported in Penn & Livingston (2006) that a time series of this magnetic field data showed a decrease in the umbral magnetic field strength which was independent of the normal sunspot cycle. Also, the measurements revealed a threshold magnetic field strength of about 1500 Gauss, below which no dark pores formed. A linear extrapolation of the magnetic field trend suggested that the mean field strength would reach this threshold 1500 Gauss value in the year 2017. Furthermore, analysis of the umbral continuum brightness showed another linear trend, and extrapolation showed the umbral brightness would be equal to the quiet Sun brightness at about the same year. Finally, the molecular line depths showed a decreasing strength with time, and again the trend suggested that molecular absorption lines would disappear from the average sunspot umbra near 2017.
There is a suite of recent astronomical and solar observational evidence that supports the assertion that the assumed fundamental mechanisms by which magnetic fields are created in stellar and very large astronomical bodies is incorrect. The seismological evidence that the solar convection is 20 to 100 times less than theoretically assumed which makes the assumed mechanism to generate the solar magnetic field not possible is only one of many.
“If these motions are indeed that slow in the Sun, then the most widely accepted theory concerning the generation of solar magnetic field is broken, leaving us with no compelling theory to explain its generation of magnetic fields and the need to overhaul our understanding of the physics of the Sun’s interior.”
http://www.nyu.edu/about/news-publi...-create-mri-of-the-suns-interior-motions.html
Anomalously Weak Solar Convection
Once the scientists captured the precise movement waves on the Sun’s surface, they were able to calculate its unseen plasma motions. This procedure is not unlike measuring the strength and direction of an ocean’s current by monitoring the time it takes a swimmer to move across the water—currents moving against the swimmer will result in slower times while those going in the same direction will produce faster times, with stronger and weaker currents enhancing or diminishing the impact on the swimmer.
What they found significantly departed from existing theory--specifically, the speed of the Sun’s plasma motions were approximately 100 times slower than scientists had previously projected.
“Our current theoretical understanding of magnetic field generation in the Sun relies on these motions being of a certain magnitude,” explained Shravan Hanasoge, an associate research scholar in geosciences at Princeton University and a visiting scholar at NYU’s Courant Institute of Mathematical Sciences. “These convective motions are currently believed to prop up large-scale circulations in the outer third of the Sun that generate magnetic fields.”
“However, our results suggest that convective motions in the Sun are nearly 100 times smaller than these current theoretical expectations,” continued Hanasoge, also a postdoctoral fellow at the Max Plank Institute in Katlenburg-Lindau, Germany. “If these motions are indeed that slow in the Sun, then the most widely accepted theory concerning the generation of solar magnetic field is broken, leaving us with no compelling theory to explain its generation of magnetic fields and the need to overhaul our understanding of the physics of the Sun’s interior.”
http://arxiv.org/pdf/1206.3173.pdf
Anomalously Weak Solar Convection
Convective velocities are 20-100 times weaker than current theoretical estimates. This suggests the prevalence of a didifferent paradigm of turbulence from that predicted by existing models, prompting the question: what mechanism transports the heat flux of a solar luminosity outwards? Advection is dominated by Coriolis forces for wavenumbers ` < 60, with Rossby numbers smaller than 102 at r=R = 0:96, suggesting that the Sun may be a much faster rotator than previously thought, and that large-scale convection may be quasi-geostrophic. The fact that iso-rotation contours in the Sun are not co-aligned with the axis of rotation suggests the presence of a latitudinal entropy gradient.