Posted on 06/30/2008 5:22:02 PM PDT by Libloather
Where are the Sunspots? Are we in for a Quiet Solar Cycle?
Written by Ian O'Neill
So what's up with our Sun? Is it going through a depression? It seems as if our closest star is experiencing a surprisingly uneventful couple of years. Solar minimum has supposedly passed and we should be seeing a lot more magnetic activity, and we certainly should be observing lots more sunspots. Space weather forecasts have been putting Solar Cycle 24 as a historically active cycle… but so far, nothing. So what's the problem? Is it a ticking bomb, waiting to shock us with a huge jump in solar activity, flares and CMEs over a few months? Or could this lack of activity a prelude to a very boring few years, possibly leading the Earth toward another Ice Age?
It's funny. Just as we begin to get worried that the next solar maximum is going to unleash all sorts of havoc on Earth (i.e. NASA's 2006 solar storm warning), scientists begin to get concerned as to whether there is going to be a solar maximum at all. In a conference last week at Montana State University, solar physicists discussed the possibility that the Sun could be facing a long period of calm, leading to the concern that there could be another Maunder Minimum. The Maunder Minimum (named after the late 19th Century solar astronomer Edward W. Maunder, who discovered the phenomenon) was a 17th Century, 30-year period when very few sunspots were observed on the disk of the Sun. It is thought by many scientists that this period contributed to what became known as the "Little Ice Age" here on Earth. As the Sun provides Earth with all its energy, during extended periods when the solar output is lower than average, it seems possible a lack of sunspots on the Sun (i.e. low activity) may be linked with periods of cold down here.
"It continues to be dead. That's a small concern, a very small concern." - Saku Tsuneta, National Astronomical Observatory of Japan and program manager for the Hinode solar mission.
However, solar physicists are not too worried about this possibility, after all, it's only been two years since solar minimum. Although activity has been low for the beginning of Cycle 24, sunspots have not been non-existent. In January of this year, a newborn spot was observed, as expected, in high latitude regions. More spots were seen in April. In March, sunspots from the previous solar cycle even made an appearance, putting on an unexpected show of flares and coronal mass ejections (CMEs).
As pointed out by David Hathaway, a solar physicist at NASA's Marshall Space Flight Center, the fact that sunspots have already been observed in this new cycle means that it is highly unlikely we face anything as extreme as another Maunder Minimum. Hathaway says there is nothing unusual about having a relatively understated solar cycle after several particularly active cycles. Solar Cycle 23 was a very active period for the Sun with a greater than average number of sunspots observed on the solar surface.
It appears there are two different predictions for the activity level of the next solar cycle. On the one hand we have scientists that think this cycle might be below average, and on the other hand we have scientists who believe the next cycle will be the biggest yet. We certainly have a long way to go before we can begin making any accurate solar forecasts…
11 years: Most obvious is a gradual increase and decrease of the number of sunspots over a period of about 11 years, called the Schwabe cycle and named after Heinrich Schwabe. The Babcock Model explains this as being due to a shedding of entangled magnetic fields. The Sun's surface is also the most active when there are more sunspots, although the luminosity does not change much due to an increase in bright spots (faculae).
22 years: Hale cycle, named after George Ellery Hale. The magnetic field of the Sun reverses during each Schwabe cycle, so the magnetic poles return to the same state after two reversals.
87 years (70–100 years): Gleissberg cycle, named after Wolfgang Gleißberg, is thought to be an amplitude modulation of the 11-year Schwabe Cycle (Sonnett and Finney, 1990).Braun, et al, (2005)
210 years: Suess cycle (a.k.a. de Vries cycle). Braun, et al, (2005).
2,300 years: Hallstatt cycle
http://en.wikipedia.org/wiki/Solar_variation
It’s probably a normal dip. Humans have been studying it for such a short time that it’s surprising to us due to lack of real observational data.
Maybe the socialist environmentalists can move the Polar Bears to the Sun since the Polar ice caps are melting.
What I want to know is, Where the H&LL are the KILLER BEES?
We were warned about them in 1978!
From BBC News [yr: 2004]:
"A new [2004] analysis shows that the Sun is more active now than it has been at anytime in the previous 1,000 years. Scientists based at the Institute for Astronomy in Zurich used ice cores from Greenland to construct a picture of our star's activity in the past. They say that over the last century the number of sunspots rose at the same time that the Earth's climate became steadily warmer."..."In particular, it has been noted that between about 1645 and 1715, few sunspots were seen on the Sun's surface. This period is called the Maunder Minimum after the English astronomer who studied it. It coincided with a spell of prolonged cold weather often referred to as the "Little Ice Age". Solar scientists strongly suspect there is a link between the two events - but the exact mechanism remains elusive."
http://news.bbc.co.uk/1/hi/sci/tech/3869753.stm
It's really hard to imagine how this little ball of fire could have any impact on our climate at all.
But the main arguments being made for a solar-climate connection is not so much to do with the heat of the Sun but rather with its magnetic cycles. When the Sun is more magnetically active (typically around the peak of the 11 year sunspot cycle --we are a few yrs away at the moment), the Sun's magnetic field is better able to deflect away incoming galactic cosmic rays (highly energetic charged particles coming from outside the solar system). The GCRs are thought to help in the formation of low-level cumulus clouds -the type of clouds that BLOCK sunlight and help cool the Earth. So when the Sun's MF is acting up (not like now), less GCRs reach the Earth's atmosphere, less low level sunlight-blocking clouds form, and more sunlight gets through to warm the Earth's surface...naturally. Clouds are basically made up of tiny water droplets. When minute particles in the atmosphere become ionized by incoming GCRs they become very 'attractive' to water molecules, in a purely chemical sense of the word. The process by which the Sun's increased magnetic field would deflect incoming cosmic rays is very similar to the way magnetic fields steer electrons in a cathode ray tube or electrons and other charged particles around the ring of a subatomic particle accelerator.-ETL
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There's a relatively new book out on the subject titled The Chilling Stars. It's written by one of the top scientists advancing the theory (Henrik Svensmark).
And here is the website for the place where he does his research:
2008: "The Center for Sun-Climate Research at the DNSC investigates the connection between variations in the intensity of cosmic rays and climatic changes on Earth. This field of research has been given the name 'cosmoclimatology'"..."Cosmic ray intensities – and therefore cloudiness – keep changing because the Sun's magnetic field varies in its ability to repel cosmic rays coming from the Galaxy, before they can reach the Earth." :
http://www.spacecenter.dk/research/sun-climate
100,000-Year Climate Pattern Linked To Sun's Magnetic Cycles:
ScienceDaily (Jun. 7, 2002) HANOVER, N.H.
Thanks to new calculations by a Dartmouth geochemist, scientists are now looking at the earth's climate history in a new light. Mukul Sharma, Assistant Professor of Earth Sciences at Dartmouth, examined existing sets of geophysical data and noticed something remarkable: the sun's magnetic activity is varying in 100,000-year cycles, a much longer time span than previously thought, and this solar activity, in turn, may likely cause the 100,000-year climate cycles on earth. This research helps scientists understand past climate trends and prepare for future ones.
http://www.sciencedaily.com/releases/2002/06/020607073439.htm
July 1st in a few hours and a low of 60 tonight and high of 82 tomorrow here in NC. I could live with this all summer.
Whewww! Looks like MY house is safe!
They did come out but only on Saturday nights. Weren't there supposed to be KILLER FRUIT FLYS? (Something illegally migrated from Mexico.)
Nice article. It goes into good detail, yet is easily comprehensible to non-solar physicists. Thanks.
Wired Magazine’s Incoherent Truths
Global warming on Free Republic
Our carbon-burning era will be a fart in the wind compared to that, timewise and effect-wise.
"Solar output"? Energy? In case the author cares, sunspots are cooler, therefore less energy reaches earth. There are certainly some intruiging theories of solar effects on weather which ultimately affect climate (e.g. electrical, UV, galactic cosmic rays), but the notion expressed above is a nonstarter.
Not exactly. Although sunspots ARE cooler than the rest of the sun's surface, as you say, there are other solar phenomena which accompanies sunspots. These phenomenon are known as 'faculae'. They are lighter, much hotter regions. However, even though there is more heat being emitted from the sun during sunspot outbreaks, it isn't believed to be all that much to make much of a difference in terms of climate on earth.
From NASA's Solar and Heliospheric Observatory's "Not So Frequently Asked Questions" section:
Q-Does the number of sunspots have any effect on the climate here on Earth?
A-Sunspots are slightly cooler areas on the surface of the Sun, due to the intense magnetic fields, so they radiate a little less energy than the surroundings. However, there are usually nearby areas associated with the sunspots that are a little hotter (called falculae), and they more than compensate. The result is that there is a little bit more radiation coming from the Sun when it has more sunspots, but the effect is so small that it has very little impact on the weather and climate on Earth.
However, there are more important indirect effects: sunspots are associated with what we call "active regions", with large magnetic structures containing very hot material (being held in place by the magnetism). This causes more ultraviolet (or UV) radiation (the rays that give you a suntan or sunburn), and extreme ultraviolet radiation (EUV). These types of radiation have an impact on the chemistry of the upper atmosphere (e.g. producing ozone). Since some of these products act as greenhouse gases, the number of sunspots (through association with active regions) may influence the climate in this way.
Many active regions produce giant outflows of material that are called Coronal Mass Ejections.
These ejections drag with them some of the more intense magnetic fields that are found in the active regions. The magnetic fields act as a shield for high-energy particles coming from various sources in our galaxy (outside the solar system). These "cosmic rays" (CRs) cause ionization of molecules in the atmosphere, and thereby can cause clouds to form (because the ionized molecules or dust particle can act as "seeds" for drop formation).
If clouds are formed very high in the atmosphere, the net result is a heating of the Earth - it acts as a "blanket" that keeps warmth in.
If clouds are formed lower down in the atmosphere, they reflect sunlight better than they keep heat inside, so the net result is cooling.
Which processes are dominant is still a matter of research.
http://sohowww.nascom.nasa.gov/classroom/notsofaq.html#SUNSPOT_CLIMATE
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