Solar Cycle Driven by More than Sunspots; Sun Also Bombards Earth with High-Speed Streams of Wind
From an NCAR press release September 17, 2009
BOULDER—Challenging conventional wisdom, new research finds that the number of sunspots provides an incomplete measure of changes in the Sun’s impact on Earth over the course of the 11-year solar cycle. The study, led by scientists at the High Altitude Observatory of the National Center for Atmospheric Research (NCAR) and the University of Michigan, finds that Earth was bombarded last year with high levels of solar energy at a time when the Sun was in an unusually quiet phase and sunspots had virtually disappeared.
“The Sun continues to surprise us,” says NCAR scientist Sarah Gibson, the lead author. “The solar wind can hit Earth like a fire hose even when there are virtually no sunspots.”
The study, also written by scientists at NOAA and NASA, is being published today in the Journal of Geophysical Research – Space Physics. It was funded by NASA and by the National Science Foundation, NCAR’s sponsor.
Scientists for centuries have used sunspots, which are areas of concentrated magnetic fields that appear as dark patches on the solar surface, to determine the approximately 11-year solar cycle. At solar maximum, the number of sunspots peaks. During this time, intense solar flares occur daily and geomagnetic storms frequently buffet Earth, knocking out satellites and disrupting communications networks.
(Illustration by Janet Kozyra with images from NASA, courtesy Journal of Geophysical Research – Space Physics.) click for larger image”]
Gibson and her colleagues focused instead on another process by which the Sun discharges energy. The team analyzed high-speed streams within the solar wind that carry turbulent magnetic fields out into the solar system.
When those streams blow by Earth, they intensify the energy of the planet’s outer radiation belt. This can create serious hazards for weather, navigation, and communications satellites that travel at high altitudes within the outer radiation belts, while also threatening astronauts in the International Space Station. Auroral storms light up the night sky repeatedly at high latitudes as the streams move past, driving mega-ampere electrical currents about 75 miles above Earth’s surface. All that energy heats and expands the upper atmosphere. This expansion pushes denser air higher, slowing down satellites and causing them to drop to lower altitudes.
Scientists previously thought that the streams largely disappeared as the solar cycle approached minimum. But when the study team compared measurements within the current solar minimum interval, taken in 2008, with measurements of the last solar minimum in 1996, they found that Earth in 2008 was continuing to resonate with the effects of the streams. Although the current solar minimum has fewer sunspots than any minimum in 75 years, the Sun’s effect on Earth’s outer radiation belt, as measured by electron fluxes, was more than three times greater last year than in 1996.
Gibson said that observations this year show that the winds have finally slowed, almost two years after sunspots reached the levels of last cycle’s minimum.
The authors note that more research is needed to understand the impacts of these high-speed streams on the planet. The study raises questions about how the streams might have affected Earth in the past when the Sun went through extended periods of low sunspot activity, such as a period known as the Maunder minimum that lasted from about 1645 to 1715.
“The fact that Earth can continue to ring with solar energy has implications for satellites and sensitive technological systems,” Gibson says. “This will keep scientists busy bringing all the pieces together.”
Buffeting Earth with streams of energy
 Sarah Gibson [ENLARGE](©UCAR, photo by Carlye Calvin.) News media terms of use* |
For the new study, the scientists analyzed information gathered from an array of space- and ground-based instruments during two international scientific projects: the Whole Sun Month in the late summer of 1996 and the Whole Heliosphere Interval in the early spring of 2008. The solar cycle was at a minimal stage during both the study periods, with few sunspots in 1996 and even fewer in 2008.
The team found that strong, long, and recurring high-speed streams of charged particles buffeted Earth in 2008. In contrast, Earth encountered weaker and more sporadic streams in 1996. As a result, the planet was more affected by the Sun in 2008 than in 1996, as measured by such variables as the strength of electron fluxes in the outer radiation belt, the velocity of the solar wind in the vicinity of Earth, and the periodic behavior of auroras (the Northern and Southern Lights) as they responded to repeated high-speed streams.
The prevalence of high-speed streams during this solar minimum appears to be related to the current structure of the Sun. As sunspots became less common over the last few years, large coronal holes lingered in the surface of the Sun near its equator. The high-speed streams that blow out of those holes engulfed Earth during 55 percent of the study period in 2008, compared to 31 percent of the study period in 1996. A single stream of charged particles can last for as long as 7 to 10 days. At their peak, the accumulated impact of the streams during one year can inject as much energy into Earth’s environment as massive eruptions from the Sun’s surface can during a year at the peak of a solar cycle, says co-author Janet Kozyra of the University of Michigan.
The streams strike Earth periodically, spraying out in full force like water from a fire hose as the Sun revolves. When the magnetic fields in the solar winds point in a direction opposite to the magnetic lines in Earth’s magnetosphere, they have their strongest effect. The strength and speed of the magnetic fields in the high-speed streams can also affect Earth’s response.
The authors speculate that the high number of low-latitude coronal holes during this solar minimum may be related to a weakness in the Sun’s overall magnetic field. The Sun in 2008 had smaller polar coronal holes than in 1996, but high-speed streams that escape from the Sun’s poles do not travel in the direction of Earth.
“The Sun-Earth interaction is complex, and we haven’t yet discovered all the consequences for the Earth’s environment of the unusual solar winds this cycle,” Kozyra says. “The intensity of magnetic activity at Earth in this extremely quiet solar minimum surprised us all. The new observations from last year are changing our understanding of how solar quiet intervals affect the Earth and how and why this might change from cycle to cycle.”
About the article
Title: “If the Sun is so quiet, why is the Earth ringing? A comparison of two solar minimum intervals”
Authors: Sarah Gibson, Janet Kozyra, Giuliana de Toma, Barbara Emory, Terry Onsager, and Barbara Thompson
Publication: Journal of Geophysical Research – Space Physics
Related sites on the World Wide Web
Whole Heliosphere Interval (2008)
h/t to Leif Svalgaard
====================================
Leif adds some perspective to this press release:
IMHO this is just another PR stunt, ‘never seen before’, ‘overturns what we thought before’, etc.
It has been known for a long time [decades] that there are strong recurrent solar wind streams leading up to solar minimum [EVERY solar minimum]. Attached are plots of the solar wind speed prior to minimum for many minima in the past. The blue curve show the speed derived from geomagnetic measurement and the pink curve shows that directly measured by spacecraft, some of the differences between the curves is due to missing data from the spacecraft [at times they only measured a small percentage of the time]. The smooth curves are 13 rotation running means.Also attached is the Recurrence Index, a measure for the recurrence tendency of the flow. High values = a solar rotation is very much like the previous one [the cross correlation between the two]
Especially the minimum in 1944 is very much like the current one in the sense that there was high-speed solar wind close to the minimum, even closer, fact. It is amazing that each new generation of scientists will have to rediscover and relearn what was already known. But such is human nature, every generation has to do this.
Ulric Lyons (05:22:49) :
I can`t find the word climate either, I must have been reading too much into “Maunder minimum”. Silly me, that`s just very low SSN and nothing to do with climate!
She was referring to the effects she had already mentioned: geomagnetic storms, aurorae, etc and how they might have been affected. In fact, one could argue that she is arguing that there may have been more of those. Remember the title of the thread: “number of sunspots provides an incomplete measure of changes in the Sun’s impact on Earth”. That is: during low solar activity there can be more high-speed streams with all their effects.
kim (04:59:38) :
It is almost inevitable that the present paradigm of understanding will change. It is in the nature of understanding if not in the nature of nature itself.
No, the current paradigm holds that the Earth is not flat, but round. That will not change. That the Sun is 149 ,597, 871 km distant on average. That will not change [except on million-year time scales]. That the mean density of the Earth is 5.5 g/cc. That will not change.
Stephen Wilde (00:36:51) :
Could there be some feature of the space between stars and galaxies that changes the speed of light with time and/or distance so that all our redshift based assumptions are merely illusions ?
I’m asking a simple question, not peddling nonsense.
No. Now, you can always adhere to Last Tuesday-ism, and claim that nobody can disprove that the Universe was created last Tuesday, with everything in it just set up to give the illusion that is was created 13.8 billion years ago, and that everything is an illusion.
On a more serious note, there is a constant of nature called the fine-structure constant. It has the value a=1/137.035999070 and is defined as a=e^2/(hc) [apart from a factor of 4pi], where e is the elementary charge, h is Planck’s constant, and c is the speed of light. A physical interpretation of a is that it is the orbital speed of an electron in the Bohr model of the hydrogen atom compared to the speed of light, i.e. the electron orbits 137 times slower than the speed of light. The importance of a is that it regulates the spectra of the elements, so that even a small change in a will result in spectra that are different from what is observed in distant galaxies. There are other ramifications of a change, e.g. the rates of nuclear decay, and the stability of atomic clocks. All our measurements are consistent with no change in a. Now, one could postulate that all the other constants also change in such a way as to give the illusion that a is also constant, and so on, but then we are back in Last Tuesday-ism.
The nonsense bit was in believing in the shells of galaxies centered on the Earth, which BTW would not result from a progressive change of c, but would require periodic changes in c [and all the other constants], contrary to what is observed.
Leif 7:10:57.
Do you purposely misunderstand? I don’t mean that all paradigms change at the same rate. Surely some paradigms aren’t very plastic. But to pretend to a perfect paradigm of cosmology is a bit absurd, really.
=========================
Leif Svalgaard (07:10:57)
Maunder minimum, low solar activity, more high-speed streams with all their effects, ~like London Frost Fairs. Confused? I get the feeling if I spoke to Sarah, we wouldn`t have to argue!
rbateman (17:33:27) :
Anything travelling along a curvature fundamentally possesses acceleration.
Process of light bent by gravity is very different mater from light bent by refraction. First has acceleration due to tangential and radial components, while in case of refraction changes speed within a single wavelength on the transition from one medium to the another. http://en.wikipedia.org/wiki/File:Snells_law.svg
http://en.wikipedia.org/wiki/Tangential_acceleration#Tangential_and_centripetal_acceleration
“Leif Svalgaard:
On a more serious note, there is a constant of nature called the fine-structure constant. It has the value a=1/137.035999070 and is defined as a=e^2/(hc) [apart from a factor of 4pi], where e is the elementary charge, h is Planck’s constant, and c is the speed of light. A physical interpretation of a is that it is the orbital speed of an electron in the Bohr model of the hydrogen atom compared to the speed of light, i.e. the electron orbits 137 times slower than the speed of light. The importance of a is that it regulates the spectra of the elements, so that even a small change in a will result in spectra that are different from what is observed in distant galaxies. There are other ramifications of a change, e.g. the rates of nuclear decay, and the stability of atomic clocks. All our measurements are consistent with no change in a.”
OK, thats fine. I see that there is a degree of cross correlation with other phenomena to verify that c at least appears to be a true constant.
I’m also content that one should only rely on that which can be demonstrated to be true even if that truth can only be demonstated in limited circumnstances.
However, I’m also aware that as far as the universe is concerned everything we see is constrained by our location and the limits to our perceptions. Thus I find it highly plausible that those constraints affect our perception of many variables simultaneously so that both a and c could well vary over time and/or distance and we would never be capable of discovering that from our limited point of view. Some undiscovered aspect of space could both alter the speed of light between far distant points and at the same time via the same process alter the appearance of the spectra reaching our instruments.
Still, I agree that that is not a scientific but rather a philosophical point. Nevertheless even the most strictly scientific mind should remain open to the most bizarre possibilities because, as Einstein and others have shown us, there are many aspects of the universe that would never have been ‘discovered’ if a strictly conventional scientific approach had been adopted.
There is a fine line between boffin and buffoon and those that stray over it should be indulged up to a point.
No smugness or self-congratulatory ignorance here. And this is a blog, not a scientific study, Leif. Lighten up.
Chris
Norfolk, VA
went to the bin?
[It’s not lost. I set it aside. It is awaiting final approval from Anthony. ~ Evan
P.S., Ook! Ook! (Scritch-Scratch) ]
i didn’t save it to a word pad—ouch
Vukcevic (09:18:18) :
Anything travelling along a curvature fundamentally possesses acceleration.
No, because the path is a geodesic in space, that is a straight line and there is no acceleration. That space is curved is another matter.
kim (07:43:12) :
But to pretend to a perfect paradigm of cosmology is a bit absurd, really.
Cosmology is not ONE paradigm: there are many paradigms and lots of established facts, among the latter that the Universe is 13.8 billion years old. That is in the same category as that of the age of the Earth is 4.55 billion years, or that my age is 67 years. It is not the nature of Nature to change these basic facts.
savethesharks (17:02:08) :
And this is a blog, not a scientific study, Leif. Lighten up.
It is also not the Jerry Springer show. And climate change is a serious thing.
Stephen Wilde (10:09:28) :
Einstein and others have shown us, there are many aspects of the universe that would never have been ‘discovered’ if a strictly conventional scientific approach had been adopted.
The conventional scientific approach includes and embraces the brilliant insights and conceptual leaps. And progress still has to be coherent and compelling, not of the ‘isn’t it conceivable that …’, or ‘since we don’t know anything, anything can happen’ kind.
P.S., Ook! Ook! (Scritch-Scratch)
Is that you feeling around at the bottom of the bin?
Did you ever get bit by anything down there?
Gene Nemetz (20:45:54) :
Google “Whale Hind Feet”
Leif Svalgaard (20:05:13) :
Vukcevic (09:18:18) :
Anything travelling along a curvature fundamentally possesses acceleration.
“No, because the path is a geodesic in space, that is a straight line and there is no acceleration. That space is curved is another matter.”
Excuse me Lief anything travelling along a curved path DOES possess acceleration. Unless classical mechanics is wrong.
Roger Carr (04:05:53) :
Discipline is not always easy, but I believe is called for here. Without trying to put words into Anthony’s mouth, nor to pre-empt him in any way, I do believe WUWT has a well defined and important mission: to foster and present reason within the sciences involved for the purpose of defeating misinformation and propaganda which will adversely affect all mankind.
Welcome to the self policed parade
Welcome to the days you’ve made
The tendency of institutional science to fall in step and cover it’s ar*e is a lot of the reason we are here.
Asking people who refused to accept the mainstream dogma about climate to fall in line in order to present some kind of ‘united front’ is just daft. The whole point is that there are so many factors and unknowns in climate that no-one is in a position to offer a complete or fully consistent theory.
In any case a good old fashioned brainstorming session around cosmology isn’t going to derail WUWT’s credibility on the climate science front, so lighten up.
tallbloke (00:42:57) “… a good old fashioned brainstorming session around cosmology isn’t going to derail WUWT’s credibility…”
In a perfect world, tallbloke, but in the present climate even minor fissures are exploited beyond proportion to project major splits appearing in the sceptical camp. The carpetbaggers are seemingly getting rather shrill, certainly desperate, and are playing a no-holds-barred game (or should that be, war?). If this was science and there were simply two “camps” tussling over theory then science would be being done. In this case it is actual-science v. control-science and the rules are different.
The implications of extremism are too serious for me to accept your advice, which in other situations I would.
Richard (22:49:01) :
Excuse me Lief anything travelling along a curved path DOES possess acceleration. Unless classical mechanics is wrong.
Which it is. The general theory of relativity supersedes classical mechanics. In General Relativity, geodesics are the trajectories of objects in freefall. For example, the moon’s trajectory around the earth is a geodesic, as is the earth’s path around the sun. All of these astronomical bodies appear to be following a curved path, but in reality are following a straight line in curved space*. This curvature is caused by the presence of a very large amount of matter, and is a phenomenon commonly known as gravity. As mentioned before, these freefall trajectories are such that no acceleration is felt. Thus, an observer in freefall feels no forces, just as if she were floating freely in outer space, in the absence of gravity. Anyone who has experienced freefall on a rollercoaster, for example, knows what this feels like.
The point here is, according to the General Relativistic model, gravity is not truly a force. Mass curves space, and curved space causes “curved” trajectories (not actually curved, just apparently curved). Thus this fundamental “force” can be described entirely by geometry, a remarkable feat indeed. For example, when the path of a light ray is “bent” by some gravitational field, it is not because gravity is “pulling” the light ray towards the source (photons are massless, and so do not “feel” a gravitational “force”). The light ray merely seeks out the shortest possible path, which may not be what we perceive to be a “straight line”.
tallbloke (00:42:57) :
In any case a good old fashioned brainstorming session around cosmology isn’t going to derail WUWT’s credibility on the climate science front
And it may be useful to take this opportunity to teach you some real science. The damage comes in when you refuse to learn and thus show a pseudo-scientific bias.
Roger Carr (02:19:25)
Hi Roger,
A serious problem for AGWers is their failing predictions. Even though the skeptics, deniers, realists, whatever they are called, may not find agreement it doesn’t matter (IMO) because the weight of obviously failing AGW predictions is what is changing the game. I think the general population doesn’t pay close attention to scientists. But they know a failed prediction when they see it.
I don’t think there has ever been perfect agreement in science about much.
Doug (14:18:02) :
Is this “high-speed stream within the solar wind that carry turbulent magnetic fields out into the solar system” the “current sheet”?
No, the streams occur on either side of the current sheet. In the current sheet itself the solar wind speed is the lowest.
I am very interested in this topic. Can you provide links for what you are saying please?
“Leif Svalgaard:
“All of these astronomical bodies appear to be following a curved path, but in reality are following a straight line in curved space*. This curvature is caused by the presence of a very large amount of matter, and is a phenomenon commonly known as gravity. As mentioned before, these freefall trajectories are such that no acceleration is felt. Thus, an observer in freefall feels no forces, just as if she were floating freely in outer space, in the absence of gravity. ”
I can see that and I think the freefall point was one that came up in a discussion of the fabled barycentre idea which postulates a gravitational interaction between the sun and the planets that can supposedly affect the energy output of the sun over time by creating variability within the sun’s interior.
Well all the planets and the sun are presumably in free fall together but that does not preclude the likelihood of a gravitational interaction between them all does it ?
Two large bodies each with a gravitational influence would still interact via gravity even though they might be in free fall together. I am thinking of the sun and Jupiter here because it is primarily the effect of Jupiter that is supposed to exert a gravitational influence on the materials of which the sun is composed.
Or have I missed something ?
.
Gene Nemetz (06:11:45) :
There are no cases of order transforming in to another order.
That is not how it works. A new order evolves from an old one, which still continues. All this is well-known, and I should not really waste everybody’s time educating you on the basics.
Stephen Wilde (10:47:09) :
Or have I missed something ?
The masses cause space to curve and the masses to follow geodesics in that curved space.
Gene Nemetz (05:59:51) :
Did you do a quick google search and come up with this?
Of course. Saves me a lot of typing.
Leif Svalgaard:
“The masses cause space to curve and the masses to follow geodesics in that curved space.”
Reply:
I know that. My question was whether multiple masses whilst in free fall together and whilst following geodesics together could nevertheless experience an interaction of forces between themselves due to the difference in their masses.
To make my point clearer, the Earth and moon are in free fall together along a geodesic curve around the sun but the moon is additonally on a geodesic curve around the Earth and all three are moving tgether on a geodesic curve through the universe.
Yet the moon nevertheless exerts tidal forces on the Earth’s oceans and I have read that the sun exerts a small tidal influence on the Earth’s interior.
Thus I have a problem ignoring the barycentric theory relating to the solar system simply on the grounds that all the components are in free fall along a geodesic curve. That may be true but I cannot see why it precludes tidal interactions between sun and planets affecting the materials which comprise each of them.
Please could you explain your objection to the concept of a solar system barycentre in view of the above.
Stephen Wilde (23:25:13) : …the moon… exerts… the sun exerts…
I have to agree with you Stephen—it seems there is gravity. 😉 That apple still falls to the ground out of the tree.
And it seems there’s a little more complexity to gravity in the universe than to simply say we are in a free fall. I think there’s something more beautiful, more ‘elegant’, going on. But that’s just how I roll.
To simply say everything is in a free fall seems primitive.
——
I remember a few months ago Anthony saying something to the effect, if I am remembering right (if I am remembering wrong moderators correct it), that he doesn’t want barycentrism discussed in WUWT anymore and that Lucy Skywalker still likes to discuss it, so to go to her blog.
Leif Svalgaard (18:18:02) :
As I already said, we have observed hundred times as many galaxies since 1990 and this large material does not show any periodicity in the redshifts.
This is because the error on those more recent studies is +-85km/s which is greater then the 72km/s observed by Tift, Arp Narliker, Guthrie and many others.
When the data with better accuracies is used, and the rest frame shfted to our galaxiy’s centre, the periodicities are there and real.
Periodicity in redshift would imply that galaxies be concentrated in concentric shells around the Earth, thus that the Earth is the center of the universe.
Wrong again. You are only forced to this conclusion if you are already assuming that the periodicities in redshift are related to velocities. It’s circular reasoning and it doesn’t hold up to scrutiny.
The evidence from the quantised redshift periodicities backs up the thesis that galaxies are not receding from us as the result of a ‘big bang’ but are revolving around their centres at fixed distances from us.
More info here :
http://ray.tomes.biz/b2/index.php/a?cat=19
And here :
http://www.bautforum.com/against-mainstream/63170-quantized-redshift-revisited.html