New Zealand Local Weather Forum
Climate and Science => Space, Science and Nature => Topic started by: Mark on March 03, 2012, 12:00:49 PM
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Sunspot numbers dropping when they should be rising
We experienced “a dramatic fall in activity” in February, says Geoff Sharp on his “Beyond Landscheidt” website. “My predictions show that SC24 will be similar to SC5.”
The sunspot number for February from SIDC is down again, to 33.1,” agrees meteorologist Anthony Watts. “So far, cycle 24 is significantly lower in SSN number that the last three cycles, in addition to having a delayed start.” Cycle 24 is so far “on par with cycle 12 and cycle 6 in amplitude.”
If Sharp and Watts are correct that solar cycle 24 will be similar to solar cycles 5 or 6 – and I fear that they are – then we’re looking at another Dalton minimum … or worse.
In other words, we could be headed toward a little ice age.
http://www.landscheidt.info/?q=node/50 (http://www.landscheidt.info/?q=node/50)
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Read about the cycle 24 Mark and it sure is a bit of a worry.
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The sun is continuing its active streak this week, firing off another solar flare late Thursday (March 8) from the same region that produced this week's strong solar storm.
An M6.3-class solar flare — a mid-range eruption — spewed from the surface of the sun last night at 10:53 p.m. EST (0353 GMT March 9), according to an alert from the Space Weather Prediction Center, a joint operation by the National Oceanic and Atmospheric Administration (NOAA) and the National Weather Service.
Space weather scientists use five categories — A, B, C, M and X — to rank solar flares based on their strength and severity. A-class flares are the weakest types of sun storms, while X-class eruptions are the most powerful.
The M-class solar flare exploded from the same sunspot region, called AR1429, which has been particularly active all week. This dynamic region has already unleashed three strong X-class solar flares. On Tuesday (March 6), two powerful X-class eruptions triggered the strongest solar storm in eight years, Bob Rutledge, head of NOAA's Space Weather Forecast Office, told reporters today (March 9).
"When you take overall intensity and length — how long it persisted — we're confident in saying by some measures, it was the strongest storm we've seen since November 2004," Rutledge said. "That doesn't mean that between November 2004 and today we haven't had brief periods that were more intense. If you look at the storm overall for length and strength, it was the strongest storm since November 2004."
A fast-moving cloud of solar plasma and charged particles, called a coronal mass ejection, was triggered by the Tuesday X-class eruptions, and this wave of energetic particles hit Earth yesterday. The resultinggeomagnetic storm was weaker than expected, but solar physicists say there is a potential for conditions to escalate.
"We still have about a 40 percent chance of seeing another X flare," Rutledge said. "We still think it's fairly likely to see one later today, tomorrow or the next day. We're watching this region closely."
A coronal mass ejection from last night's flare is also approaching Earth, and while this one is expected to hit Earth directly on Sunday (March 11), experts at the Space Weather Prediction Center are not anticipating the effects to be very severe.
"[It] could cause storming levels that could reach the G3 (strong) level again, but we don't believe it will have quite the sustained intensity," Rutledge said.
Still, the massive sunspot region shows no signs of quieting down, and earlier today, NASA scientists said that it also appears to be growing.
"Sunspot AR1429 keeps getting bigger! It's more than 7 times the width of Earth," scientists with NASA's Solar Dynamics Observatory said via Twitter.
With this sunspot region now facing Earth, at the central meridian of the solar disk, strong solar eruptions have the potential to wreak havoc on the planet. Big coronal mass ejections that hit Earth head-on can potentially knock out power grids and disrupt other electronics infrastructure. Strong solar storms can also disrupt satellites in space and pose radiation risks for astronauts aboard the International Space Station.
This week's solar storm increased levels of solar radiation and caused geomagnetic storms on Earth, but the effects were milder than expected. As a precaution, commercial airliners re-routed flights over Earth's polar caps, but no other major disruptions were reported, Rutledge said.
Solar storms can also amp up displays of the northern and southern lights, enabling people to see them farther south than normal. Yesterday, skywatchers reported seeing auroras from states such as Wisconsin, Michigan and Washington, Rutledge said.
But without any additional eruptions from the sun, and as this week's solar storm begins to taper off, the supercharged aurora displays will begin to decrease around the globe, he added.
The sun appears to be coming out of an extended lull in activity in its 11-year cycle. The current cycle is known as Solar Cycle 24 and solar activity is expected to ramp up toward its peak in 2013, NASA officials have said.
By Denise Chow, SPACE.com
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Third straight month of dropping sunspot numbers
Dropping. When they should be rising.
NOAA data also shows that, like the sunspot numbers, the 10.7cm flux is also down for the 3rd straight month.
Now it will be interesting to see what happens to our climate.
http://www.swpc.noaa.gov/SolarCycle/ (http://www.swpc.noaa.gov/SolarCycle/)
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NASA/Hathaway’s updated solar cycle prediction – smallest in 100 years
From: http://solarscience.msfc.nasa.gov/predict.shtml
The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 60 in the Spring of 2013. We are currently over three years into Cycle 24. The current predicted size makes this the smallest sunspot cycle in about 100 years.
The prediction method has been slightly revised. The previous method found a fit for both the amplitude and the starting time of the cycle along with a weighted estimate of the amplitude from precursor predictions (polar fields and geomagnetic activity near cycle minimum). Recent work [see Hathaway Solar Physics; 273, 221 (2011)] indicates that the equatorward drift of the sunspot latitudes as seen in the Butterfly Diagram follows a standard path for all cycles provided the dates are taken relative to a starting time determined by fitting the full cycle. Using data for the current sunspot cycle indicates a starting date of May of 2008. Fixing this date and then finding the cycle amplitude that best fits the sunspot number data yields the current (revised) prediction.
Click on image for larger version.
Predicting the behavior of a sunspot cycle is fairly reliable once the cycle is well underway (about 3 years after the minimum in sunspot number occurs [see Hathaway, Wilson, and Reichmann Solar Physics; 151, 177 (1994)]). Prior to that time the predictions are less reliable but nonetheless equally as important. Planning for satellite orbits and space missions often require knowledge of solar activity levels years in advance.
A number of techniques are used to predict the amplitude of a cycle during the time near and before sunspot minimum. Relationships have been found between the size of the next cycle maximum and the length of the previous cycle, the level of activity at sunspot minimum, and the size of the previous cycle.
Among the most reliable techniques are those that use the measurements of changes in the Earth’s magnetic field at, and before, sunspot minimum. These changes in the Earth’s magnetic field are known to be caused by solar storms but the precise connections between them and future solar activity levels is still uncertain.
Of these “geomagnetic precursor” techniques three stand out. The earliest is from Ohl and Ohl [Solar-Terrestrial Predictions Proceedings, Vol. II. 258 (1979)] They found that the value of the geomagnetic aa index at its minimum was related to the sunspot number during the ensuing maximum. The primary disadvantage of this technique is that the minimum in the geomagnetic aa index often occurs slightly after sunspot minimum so the prediction isn’t available until the sunspot cycle has started.
An alternative method is due to a process suggested by Joan Feynman. She separates the geomagnetic aa index into two components: one in phase with and proportional to the sunspot number, the other component is then the remaining signal. This remaining signal has, in the past, given good estimates of the sunspot numbers several years in advance. The maximum in this signal occurs near sunspot minimum and is proportional to the sunspot number during the following maximum. This method does allow for a prediction of the next sunspot maximum at the time of sunspot minimum.
A third method is due to Richard Thompson [Solar Physics 148, 383 (1993)]. He found a relationship between the number of days during a sunspot cycle in which the geomagnetic field was “disturbed” and the amplitude of the next sunspot maximum. His method has the advantage of giving a prediction for the size of the next sunspot maximum well before sunspot minimum.
We have suggested using the average of the predictions given by the Feynman-based method and by Thompson’s method. [See Hathaway, Wilson, and Reichmann J. Geophys. Res. 104, 22,375 (1999)] However, both of these methods were impacted by the “Halloween Events” of October/November 2003 which were not reflected in the sunspot numbers. Both methods give larger than average amplitude to Cycle 24 while its delayed start and low minimum strongly suggest a much smaller cycle.
The smoothed aa index reached its minimum (a record low) of 8.4 in September of 2009. Using Ohl’s method now indicates a maximum sunspot number of 70 ± 18 for cycle 24. We then use the shape of the sunspot cycle as described by Hathaway, Wilson, and Reichmann [Solar Physics 151, 177 (1994)] and determine a starting time for the cycle by fitting the latitude drift data to produce a prediction of the monthly sunspot numbers through the next cycle. We find a maximum of about 60 in the Spring of 2013. The predicted numbers are available in a text file, as a GIF image, and as a pdf-file. As the cycle progresses, the prediction process switches over to giving more weight to the fitting of the monthly values to the cycle shape function. At this phase of cycle 24 we now give 66% weight to the amplitude from curve-fitting technique of Hathaway, Wilson, and Reichmann Solar Physics 151, 177 (1994). That technique currently gives similar values to those of Ohl’s method.
Note: These predictions are for “smoothed” International Sunspot Numbers. The smoothing is usually over time periods of about a year or more so both the daily and the monthly values for the International Sunspot Number should fluctuate about our predicted numbers. The dotted lines on the prediction plots indicate the expected range of the monthly sunspot numbers. Also note that the “Boulder” numbers reported daily at www.spaceweather.com are typically about 35% higher than the International sunspot number.
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 GIF image, and as a pdf-file. Current values for F10.7 can be found at: http://www.spaceweather.ca/sx-4-eng.php.
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Fascinating - thanks Mark! When they say the "smallest" cycle - does that mean just in the peak sunspot numbers or also in period as judging by previous minimum date to peak, is not half of an eleven year period... it is slightly less. Unless the shape is non linear or not reflective about the max.
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Hi TokWW,
I think its the sunspot number.
I have heard that this may be a long Cycle with a lower sunspot number.
We just have to wait and see i think its all a bit new as this cycle is not the same as the past few cyces.
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26 September 2012 by Stuart Clark
Magazine issue 2884. Subscribe and save
For similar stories, visit the Solar System Topic Guide
WAITING for solar fireworks to reach a grand finale next year? Um, sorry, looks like you already missed them. Structures in the sun's corona indicate that the peak in our star's latest cycle of activity has been and gone, at least in its northern hemisphere.
The southern hemisphere, meanwhile, is on a sluggish rise to solar maximum and may not hit its peak until 2014.
This bizarre asymmetry strengthens a theory that has been bubbling among sun watchers for the past few years: our star is headed for hibernation. Having the sun's outbursts turned off for a while would provide a better baseline for studying how they influence Earth's climate.
Observations of magnetic footprints called sunspots revealed in the 1800s that the sun moves through a roughly 11-year cycle of activity. Around a solar maximum, the star ramps up production of sunspots, flares and ejections of plasma. During a solar minimum, things quieten down.
Following an unexpectedly deep minimum from 2008 to 2010, solar physicists predicted a weak maximum for 2013. These days, though, sunspots aren't the only tools for charting the solar cycle. Richard Altrock of the US Air Force Research Laboratory in New Mexico has been studying coronal structures called polar crown prominences, which stem from magnetic rumblings on the sun's surface.
These gaseous filaments form at mid-latitudes at the beginning of a solar cycle. As it progresses they drift polewards, and when they reach 76 degrees latitude, a solar maximum has arrived. Soon afterwards the prominences disappear, only to form again during the next cycle.
Based on the movements of this cycle's prominences, Altrock says that an especially weak solar maximum took place in the sun's northern hemisphere around July last year (arxiv.org/abs/1209.2969).
Bernhard Fleck, project scientist for NASA's and the European Space Agency's Solar and Heliospheric Observatory, calls the paper solid work, but adds that even if we missed the northern maximum, the southern hemisphere is still expected to put on a show.
According to Altrock, the southern prominences are still on the move, but slowly. If they continue at the current rate, he says, the south will not reach its maximum until February 2014.
Such a large asymmetry between hemispheres could be a sign of big changes ahead, says Steven Tobias, a mathematician at the University of Leeds, UK, who models what drives the sun's magnetic field. According to his models, such a situation precedes an extended quiet phase called a grand minimum. "Changes in symmetry are more indicative of going into a grand minimum than the strength of the cycle," he says.
Grand minima can last for decades. The previous one took place between 1645 and 1715, and has been linked to the little ice age in Europe. A new one might also cause localised cold periods, but many climate scientists see a silver lining to such a turn of events: a grand minimum offers ideal conditions for testing the effects of solar variability on Earth's climate (see "Our star's subtle influence").
But Michael Proctor, a solar physicist at the University of Cambridge, is not convinced that this will happen. "This present cycle is similar to the weak one that ended in 1913, and that was followed by a strong cycle," he says.
Only time will tell.
http://www.newscientist.com/article/mg21528843.700-solar-maximum-oh-you-just-missed-it.html
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Something strange, very strange, is happening on the sun. On October 8th, NOAA’s Solar Cycle Progression monthly update report came out.
Sunspot activity has dropped off to its lowest point in over 100 years, perhaps to its lowest since the Dalton Minimum of the early 1800s.
The sun is headed into a quiet phase. The evidence is mounting. Sunspot activity is down. Solar flux is down. The sun’s magnetic field is decreasing linearly toward zero by 2026. The long term trend points towards a less active sun.
Solar physicists believe a prolonged period of low solar activity lasting more than one cycle is coming.
This change in the sun’s behavior could have profound long-term implications for climate change over the next several decades.
What’s Happening on the Sun?
2012 Solar Sunspot Activity through September highlighted in Yellow
The trend for 2012 is set. According to NOAA, September’s sunspot number was 61.5. After a giant hiccup in solar activity late last year the sunspot number for 2012, so far, has settled down to only 59.5.
By international standard, the sunspot number is a measure of the average number of sunspots over time, usually a year. Monthly averages are also published during the year. That is what NOAA just reported. See 2012′s sunspot numbers highlight in yellow above.
Magnetic Field Trend Line
Its certainly possible sunspot activity could pick up. The sun is prone to wild fluctuations, but unlikely to go up much this time. The peak of sunspot activity this cycle has already passed for the sun’s northern hemisphere.
Even if 2013′s forecast high of 75 is reached it would still be among the lowest on record. It doesn’t look like even that will be reached.
The last sunspot cycle, cycle 23, had an unexpectedly long minimum extended nearly two years. Solar sunspot activity this cycle is half what it was last cycle.
The Great Solar Divide
Reporting on the Japanese Hinode mission to the sun, NASA says an asymmetry has developed between the sun’s northern and southern hemispheres.
During every solar cycle sunspot activity begins at its equator and advances toward the poles until it peaks at about 76º north and south. What is different about this cycle is the northern progression has already peaked and turned around. The south still has a ways to go before it peaks. Its flattening out solar maximum.
This flattening asymmetry is turning the world of solar physics upside down. The current model will have to change. Space weather forecasting, an infant science, is evolving rapidly.
As recently as August 2004, NASA’s David Hathaway forecast the current solar cycle would peak at 145 in 2010! Every time since then he (and others) have lowered the peak and pushed it further out. Hathaway’s current prediction is down to 75 that peaks in late 2013.
Its exciting! Hinode and other instruments are studying the current solar cycle, cycle 24, to a deeper level of detail than ever before. That promises to increase our understanding of solar physics and greatly advance the ability to predict the sun’s future behavior.
Trends in Solar Activity
Yellow highlight shows current solar cycle (24) near solar max as of October 2012
In 1700 the sun was just coming out of the longest period of sunspot inactivity known. It is called the Maunder Minimum. The Dalton Minimum followed closely on its heels. It lasted for two solar cycles in the early 1800s.
That was followed by the Modern Maximum that peaked the middle of last century. That maximum is among the highest periods of solar activity of the last 11,500 years going back to the last ice age.
Solar activity has been on the decline ever since.
Now solar physicists tell us to expect another minimum lasting more than one cycle.
Solar Activity and Climate Change
The Maunder and Dalton minimums share one thing in common. Both are associated with cold periods in Earth’s climate history. The time of the Maunder Minimum is often referred to as the “Little Ice Age“.
It is probably not entirely by chance that the Modern Maximum and another earlier period of high solar activity, the Medieval Warm Period, both correspond to warmer temperatures in Earth’s recent climate history.
In the satellite era it has been found the sun varies in radiant energy from 0.1% to 0.2% over a solar cycle. It is hottest during maximum solar activity. That could be a forcing mechanism driving historical climate change, just like the IPCC says CO2 is today.
It is unknown what the cooling effect of a prolonged period of inactivity might be. Physics cannot yet answer that question, but a long history of anecdotal empirical evidence suggests it does.
Conclusions
There is little doubt that human CO2 emissions have played a significant role in Earth’s current warm period. The Earth is about 1°C warmer than it was in 1880.
The IPCC has considered but rejected solar activity as a cause. The IPCC has rejected all possible causes of current global warming except AGW – Anthropogenic (human caused) Global Warming.
Times are a changin’! The impact of solar variation is becoming clearer.
The amount of irradiance change so far directly measured on the sun is insufficient to explain the global warming observed. But direct radiant energy variations have only been measurable since about 1975, a period covering three of the highest solar cycles ever seen.
It is completely unknown how much cooling happens during prolonged periods of inactivity like we are entering now. That has yet to be measured. The lesson of history teaches us there will be a noticeable effect.
Here is the $100 trillion question:
Will AGW or solar variation dominate climate change in the coming decades?
http://informthepundits.wordpress.com/2012/10/11/climate-change-and-the-quiet-sun/
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October 24, 2012 – SPACE – New sunspot AR1598 has erupted again. On Oct. 23rd at 0322 UT, Earth orbiting satellites detected a strong X1-class solar flare. NASA’s Solar Dynamics Observatory recorded the extreme ultraviolet flash: Radiation from the flare created waves of ionization in the upper atmosphere over Asia and Australia (the daylit side of Earth) and possibly HF radio blackouts at high latitudes. The blast did not, however, produce a significant coronal mass ejection (CME). No auroras are expected to result from this event. This is the 4th significant flare from AR1598 since it emerged over the southeastern limb only three days ago. This means more flares are probably in the offing, and they will become increasingly Earth-directed as the sunspot turns toward our planet in the days ahead. –Space Weather
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Have we hit solar max?
NOAA’s SWPC recently updated their solar metrics graphs, and it seems to me like we may have topped out for solar cycle 24. There doesn’t seem to be any evidence of resurgence in any of the three metrics. Granted one month does not a cycle make, but it has been over a year now since the peak of about 95 SSN in October 2011, and there has been nothing similar since. Unlike the big swings of last solar max around 2000-2001, there’s very little variance in the signals of the present, demonstrating that the volatility expected during solar max just isn’t there
It has been 7 years since the regime shift was observed in the Solar Geomagnetic Index (Ap) in October 2005, and the sun seems to be in a generally quiet magnetic period since then with no hint of the volatility of the past cycle.
UPDATE: Another indicator that we are at solar max is that the polar magnetic fields are about to flip, as tracked in this graphic from Dr. Leif Svalgaard. Click image to enlarge:
http://www.swpc.noaa.gov/
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you could argue that the peak already, and not a very good peak, is why El Nino has struggled to get going this year
(El Nino's tend to be best around peak sun spot years (i.e when the sun is more active))
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December 30, 2012 – SPACE – SOLAR CYCLE UPDATE: 2013 is only days away, and according to most forecasters, Solar Max should be approaching as well. But is it? Barely-increasing sunspot counts and anemic solar activity suggest an interesting possibility: Perhaps Solar Max is already here. (Below) This plot of measured vs. predicted sunspot numbers illustrates the idea: The blue curve traces monthly sunspot numbers measured since 2000. The red curve is the prediction of the NOAA-led Solar Cycle Prediction Panel. So far, Solar Cycle 24 is underperforming even compared to the panel’s low expectations. There is still a strong chance that Cycle 24 will rebound and peak in 2013 as expected. It might even be a double-peaked cycle like the cycle before it. As 2013 nears only one thing is certain: we don’t know what will happen. Stay tuned. –Space Weather
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The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 69 in the Fall of 2013. The smoothed sunspot number has already reached 67 (in February 2012)due to the strong peak in late 2011 so the official maximum will be at least this high and this late. We are currently over four years into Cycle 24. The current predicted and observed size makes this the smallest sunspot cycle since Cycle 14 which had a maximum of 64.2 in February of 1906.
The prediction method has been slightly revised. The previous method found a fit for both the amplitude and the starting time of the cycle along with a weighted estimate of the amplitude from precursor predictions (polar fields and geomagnetic activity near cycle minimum). Recent work [see Hathaway Solar Physics; 273, 221 (2011)] indicates that the equatorward drift of the sunspot latitudes as seen in the Butterfly Diagram follows a standard path for all cycles provided the dates are taken relative to a starting time determined by fitting the full cycle. Using data for the current sunspot cycle indicates a starting date of May of 2008. Fixing this date and then finding the cycle amplitude that best fits the sunspot number data yields the current (revised) prediction.
NOAA’s Space Weather Prediction Center
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The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 69 in the Fall of 2013. The smoothed sunspot number has already reached 67 (in February 2012)due to the strong peak in late 2011 so the official maximum will be at least this high and this late. We are currently over four years into Cycle 24. The current predicted and observed size makes this the smallest sunspot cycle since Cycle 14 which had a maximum of 64.2 in February of 1906.
The prediction method has been slightly revised. The previous method found a fit for both the amplitude and the starting time of the cycle along with a weighted estimate of the amplitude from precursor predictions (polar fields and geomagnetic activity near cycle minimum). Recent work [see Hathaway Solar Physics; 273, 221 (2011)] indicates that the equatorward drift of the sunspot latitudes as seen in the Butterfly Diagram follows a standard path for all cycles provided the dates are taken relative to a starting time determined by fitting the full cycle. Using data for the current sunspot cycle indicates a starting date of May of 2008. Fixing this date and then finding the cycle amplitude that best fits the sunspot number data yields the current (revised) prediction.
http://solarscience.msfc.nasa.gov/predict.shtml
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looks like alarm bells were going off that did not need to be as much
still going to be a low peak by the looks
and yet the world is still warmer than normal...
if we had another big peak like 1999/2000, then would have passed the hottest year being 1999 instead of equalling it or so for the globe, ?
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The strongest solar flare in quite some time took place within the past couple of hours around Sunspot 1719. The moderately strong event measuring M6.5 took place at 07:16 UTC. A Coronal Mass Ejection (CME) is now visible in the latest STEREO Ahead and STEREO Behind COR2 imagery. Because 1719 is now squarely facing Earth, the plasma should be directed this way. This will raise the chances of geomagnetic storming by this weekend. Stay Tuned to SolarHam.com for the latest information.
http://www.solarham.net/
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Sunspot count is virtually unchanged from last month :
It seems possible that we’ve seen the double peak, and it will be downhill after this.
A similar status quo in radio flux – little change from last month.
The Ap magnetic index dropped 4 units from last month, suggesting a slowing in the solar dynamo.
About the only significant even in the last month is that the solar polar fields have begun their reversal, indicating we are at “solar max”, which seems like a misnomer given the low activity observed at the moment. That’s why I think we may have seen the “double peak” and it is downhill from here.
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Something is up with the sun.
Scientists say that solar activity is stranger than in a century or more, with the sun producing barely half the number of sunspots as expected and its magnetic poles oddly out of sync.
The sun generates immense magnetic fields as it spins. Sunspots—often broader in diameter than Earth—mark areas of intense magnetic force that brew disruptive solar storms. These storms may abruptly lash their charged particles across millions of miles of space toward Earth, where they can short-circuit satellites, smother cellular signals or damage electrical systems.
Based on historical records, astronomers say the sun this fall ought to be nearing the explosive climax of its approximate 11-year cycle of activity—the so-called solar maximum. But this peak is "a total punk," said Jonathan Cirtain, who works at the National Aeronautics and Space Administration as project scientist for the Japanese satellite Hinode, which maps solar magnetic fields.
"I would say it is the weakest in 200 years," said David Hathaway, head of the solar physics group at NASA's Marshall Space Flight Center in Huntsville, Ala.
Researchers are puzzled. They can't tell if the lull is temporary or the onset of a decades-long decline, which might ease global warming a bit by altering the sun's brightness or the wavelengths of its light.
http://online.wsj.com/news/articles/SB10001424052702304672404579183940409194498