Okay ... so it's a big picture. I still thing that this is such a beautiful
picture, taken by the Swedish Observatory, that I was compelled to show it in
a large format. Be glad that I shrunk it down to a fourth of the original. This
amazing sunspot photograph is here to lead into a lesson tied to global warming
and an interesting prediction. Every 11 years, on average, the Sun experiences
a peak in solar activity and a reversal of the magnetic field. The last reversal
of the magnetic field was completed by February,
2001. This peak is called "SolarMax" and the violence that occurs
within the Sun and out from its "surface" is now the subject of such
intense study that I have devoted a page to this peak of activity.
In this page, you will learn that the Sun has an 11 year period of low or
no sunspot activity and high sunspot activity. At the peak of solar activity,
the entire Sun undergoes a dramatic shift of his global magnetic field. The
north pole becomes magnetic south, and the south pole becomes magnetically north.
The ferocious action of the Sun during this time poses great dangers to any
electronic instruments we have in space, as well as on the ground.
The Connection Between the Sunspot Cycle and the Stradivarius Violin
may have made his name famous with his discovery of the Sunspot Cycle, and he
even has a 70 year period of history named after himself ... "The
Maunder Minimum." Well, another individual benefitted from this unusual
period of time between 1645 and 1715. It appears possible that the famous Italian
violin-maker Stradivari, may have made perfect-sounding violins, in part, because
he used perfect trees grown during the Maunder Minimum. Read below and click
on the sites for more.
and climatologist Lloyd Burckle of Columbia University in New York have come
up with an (interesting) hypothesis. They suggest that climatic cooling over
many decades affected rates of tree growth and may have contributed to the acoustic
quality of the violins produced by Stradivari and his contemporaries. Dense
wood with narrow growth rings may help to "instill a superior tone and
brilliance in violins," the researchers wrote, adding that wood grown under
fast conditions is less resonant and unlikely to survive the stresses placed
on a violin."Much of Europe was gripped by the little ice age between around
1400 and 1800," said Grissino-Mayer, noting that the period of cold weather
and long winters peaked between 1645 and 1715. Trees growing during that peak
period, the so-called Maunder Minimum, "showed the slowest growth rates
of the entire last 500 years," he said.
Intriguingly, Stradivari was born one year before the start of the Maunder
Minimum. He produced violins from 1666 until his death in 1737. Other studies
have shown that Stradivari used violins built from spruce wood contemporary
to his lifetime, and Grissino-Mayer believes this would have been locally obtained.
Still, scientists like Grissino-Mayer don't discount the unique talents Stradivari
and his contemporary artisans brought to producing wonderful-sounding violins.
"They didn't only have better materials
the skills of the maker
will have a considerable effect on the tonal quality of the final instrument,"
Basically, what the printed words in the article are saying is that the complete
lack of sunspots for 70 years resulted in an unusually consistent solar output.
It is believed that the trees that were growing at this time would have experienced
consistent growth seasons for 70 years, and would have nearly identical tree
rings for that 70 year period of time. In other words, the tree wood would be
perfect. When Stradivari cut the wood for his violins, the tone produced would
be more pure than with wood cut from trees that had irregular growth rings.
Certainly his technique of soaking the wood, cutting, and bending the wood are
marvelous, but these techniques have been reproduced many times and yet never
with the same tones of the original violins.
The Danger of Solar Flares
Solar Flares, associated with Solar Maximum are powerful eruptions that can
do tremendous damage to space satellites and ground-based power systems. Read
the articles below, and click on the links, to learn about the damage that a
powerful flare can wreak upon the Earth.
"Astronomers rank solar flares into five categories according to the
extent to which they emit X-rays. Class X is the most powerful, being tens times
the intensity of M-class flares. Flares are characterized by their brightness
in X-rays (X-Ray flux), the GEOS Class. The biggest flares are X-Class flares.
M-Class flares have a tenth the energy and C-Class flares have a tenth of the
X-ray flux seen in M-Class flares.
The sun has an 11-year cycle of behavior which peaked in 2000. One on March
6, 1989 knocked out power to the Canadian province of Quebec. In 1997, an AT&T
Telestar 401 satellite used to broadcast television shows from networks to local
affiliates was knocked out during a solar storm. In May 1998 a solar blast disabled
PanAmSat's Galaxy IV. Among the casualties: automated teller machines; gas station
credit card handling services; 80 percent of all pagers in the United States;
news wire service feeds; CNN's airport network; and some airline weather tracking
A space storm also heats the upper level of Earth's atmosphere, causing it
to expand. That's no good for satellites that can get caught up in air that
didn't used to be there. Communication disruptions can occur without actually
damaging satellites. Even cell phone towers can be zapped, causing dropped calls.
The greatest solar storm on record (prior to the Nov. 2003 storm) occurred in
1859, shorting out telegraph wires and starting fires in the United States and
Europe. Paal Brekke, SOHO deputy project scientist, told SPACE.com this week's
storm, if it hooks up with Earth in just the right way, would be about one-third
as strong as the 1859 tempest. "
On March 13, 1989, at 2:44 am, a transformer failure on one of the main power
transmission lines in the HydroQuebec system precipitated a catastrophic collapse
of the entire power grid. The string of events that produced the collapse took
only 90 seconds from start to finish. There was no time for any meaningful intervention.
The transformer failure was a direct consequence of ground induced currents
from a space weather disturbance high in the atmosphere. 6 million people lost
electrical power for 9 or more hours.
The SMM (Solar Maximum Mission) satellite dropped 3 miles from its normal
orbit due to increased drag.
Local radio transmissions in Minnesota were overpowered by California Highway
Geomagnetically-induced-currents caused a major power failure at the Hydro-Quebec
Power Company leaving 6 million people without electricity for 9 hours and a
$26 mllion transormer melted down at a New Jersey Public Service Company plant.
The space weather disturbance that produced this devastation was a great magnetic
storm. Great magnetic storms are awesome disturbances in the near-Earth space
environment that occur relatively rarely. The last five occurred in February
1986, March 1989, March 1991, November 1991 and May 1992. The frequency of large
and great storms increases markedly as we enter the maximum in the solar activity
cycle. The latest maximum was in the year 2000 (the previous solar maximum was
in 1989). Better warning of impending space weather events would allow power
companies to take steps to reduce the load on sensitive circuits, delay maintenance
and equipment replacement, prevent the development of large potential drops
by selectively grounding sensitive devices and inteligently deal with systems
designed to automatically protect the network during the duration of the event.
This is the best way to prevent costly and dangerous black out situations triggered
by space weather events.
At a news conference earlier in January during the annual meeting of the American
Astronomical Society in Austin, Tex., Schaefer and his colleagues reported that
nine stars on which superflares have been observed during the past century are
disturbingly similar to the Sun in size, age, luminosity and rotation speed.
(Other collaborators on the research were Jeremy R. King, Space Telescope Science
Institute, Baltimore, Md.; and Constantine P. Deliyannis, Indiana University,
"It's only natural to ask what would happen on Earth if such a superflare
were to suddenly occur on our Sun, or to speculate why such flares apparently
have not happened here," Schaefer says. He notes that a superflare -- a
flare 100 to 10 million times larger than the largest flare ever seen on the
Sun -- would severely disrupt radio communication, burn out all orbiting satellites,
black out power grids worldwide and create spectacular auroras visible from
the poles to the equator.
"Large superflares could warm a cold winter day into a hot summer day,"
he says. "But the primary damage would come from high energy radiation,
which would react in the Earth's upper atmosphere to destroy the protective
ozone layer for several years, thereby exposing the Earth's surface to harmful
ultraviolet radiation with subsequent collapse of the food chain."
Fortunately, such grim possibilities appear to be unlikely, the researchers
agree. Any superflares on the Sun during the last 150 years of scientific monitoring
would certainly have been noted, while any superflare within the last two millennia
would likely have appeared in the historical record as a sudden heat wave or
global aurora, Schaefer says. Furthermore, a large superflare probably would
have melted the icy surfaces of moons around Jupiter and Saturn, forming vast
flood plains. The absence of smooth frozen surfaces on these moons means that
large superflares have not occurred in the last billion years or so.
"Despite the myth of Phaëthon, our Sun apparently has only rare
superflares, if any," Schaefer concludes.
Stars like the Sun have superflares an average of about once a century, the
researchers calculate, and it is just this type of star around which planets
recently were discovered, opening the door to the possibility of organic life
flourishing elsewhere. It is unknown whether recurring superflares would encourage
evolution by providing an energy source for prebiotic chemical reactions or
would prevent new lifeforms from gaining a foothold.
What is all of this telling us?
It is telling us that the Sun is not a constant star and that changes on the
Sun's surface, changes in the Sun's magnetic field, and changes in the Sunspot
Cycle can have global effect on the Earth, and may have played a role in the
development of life. This last article is extremely intriguing for it holds
the possibility that large flares may have happened in the past, not once per
century, but once every few millions of years. The fossil record of life is
NOT a continuous record of gradual change over time, but full of gaps. Individual
rock strata have representative fossils found in no other strata. Is it possible
that large flares happened in the episodic past, wiped out much of the ozone
layer, caused organisms to experience high mutation rates, and evolve rapipdly?
Is this a potential mechanism to support Stephan Jay Gould's "punctuated
equilibrium" method of evolution and the cause of so many missing links?
If you want to know more, go to Fossil
Record in this course, or take AP Biology where this topic is taught more
The Sunspot Cycle had a glitch in 2000 when it dropped through 2002, but then
rose again to form a second hump in 2004 (seen above). And if these solar flares
and extended Solar Maximums are not enough to get your attention and wonder
about the effect that the Sun has on this planet, check out the Solar
Storm of October 26, 2003 within the pages of this course. I was outside
to watch the brillian green and red auroras on this evening, and my students
called my cell phone (fortunately it was working) to tell me what they were
seeing from their homes. My point in these pages is to alert you to the possibility
of damage from a major solar eruption. Just when you think you are safe in the
friendly confines of your home ... bang ... the Sun erupts. Since we see the
eruption visually before the damage arrives, we will at least have 36 hours
or so to wait in peace before much of the ozone layer is destroyed. See what
else happened as a result of this 2003 Solar Storm in your reading below!
Solar Flares Can Destroy Parts of the Ozone Layer Too
A dramatic thinning of Earth's protective ozone layer above the Arctic last
year was the result of intense upper-level winds and an extra dose of space
weather, scientists said Tuesday. Ozone, which screens out some of the Sun's
harmful ultraviolet radiation, declined by up to 60 percent in the stratosphere
over high northern latitudes in the spring of 2004. Officials issued a health
warning earlier this year for residents of the far North. In a new study, scientists
conclude that an intense round of solar storms around Halloween in 2003 was
at the root of the problem. Charged particles from the storms triggered chemical
reactions that increased the formation of extra nitrogen in the upper stratosphere,
some 20 miles up. Nitrogen levels climbed to their highest in at least two decades.
A massive low-pressure system that confines air over the Arctic then conspired
to deplete ozone.
The most extreme solar flare ever recorded erupted on Nov. 4, 2003. The flare
spawned this coronal mass ejection, which hurled charged particles into space.
The storm was one of 10 major solar eruption to occur in an unprecedented two-week
span of solar storminess. Upper-atmosphere winds associated with the system,
called the polar stratospheric vortex, sped up in February and March of 2004
to the fastest speeds ever recorded, the new study found. The spinning vortex
allowed nitrogen gas to sink from the high stratosphere, some 20 miles up, to
lower altitudes. The nitrogen gas is known to destroy ozone.
"This decline was completely unexpected," said Cora Randall, a physicist
at the University of Colorado, Boulder who led the study. "The findings
point out a critical need to better understand the processes occurring in the
ozone layer." Researchers from Canada and Europe contributed to the study,
which drew data from seven satellites. The results are detailed in the March
2 online issue of Geophysical Research Letters, published by the American Geophysical
Union. Ozone is a form of oxygen. Its protective qualities make life as we know
it possible. (Near the ground, ozone plays the opposite role, being the main
component in smog.) The upper-level ozone layer has thinned dramatically in
the Southern Hemisphere in recent decades, creating a dangerous hole through
which UV rays stream. The decline is due largely to man-made chlorofluorocarbons
released into the atmosphere.
The new study suggests a better understanding is needed of how the Sun itself
alters the ozone layer. "No one predicted the dramatic loss of ozone in
the upper stratosphere of the Northern Hemisphere in the spring of 2004,"
Randall said. "That we can still be surprised illustrates the difficulties
in separating atmospheric effects due to natural and human-induced causes."
The thinning of the Arctic ozone layer continues, owing in part to cold temperatures
in the stratosphere, according to a separate recent study that suggests a northern
hole could develop as a twin to the southern one.
Oh, and just to make you fear some more, scientists just predicted that the
next SolarMax will be significantly more powerful and dangerous than past cycles
... 30 to 50% more powerful!. Check this out at Science
Okay ... enough of the doom and gloom around Solar Storms and Solar Max. At
least we will see some pretty auroras:) Time to move on in your learning be
returning to the Sun Features Unit,
or to the Syllabus.
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