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
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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.
scholraly
Great!
Leif:
Do you believe that the Maunder and Dalton minimums were colder epochs?
If the answer is yes, then these colder episodes were clearly linked to lower Sunspot activity, so what in the Sun’s output could be causing such temperature changes?
Electro-magnetic radiation, magnetic flux, solar wind – is there anything else we have missed? Nutrinos?
.
Is this not a pre-Copenhagen pre-emptive strike against any mention of a “quiet sun” during the conference? “See, lots of other energy stuff coming from the sun, CO2 is the problem”.
Leif,
On Dec. 15, 2008 NASA anounced there was a burst of regular protons that was preceeded by a stream of intact hydrogen atoms. How common do you think these are and what effect do you think they may have on the atmosphere?
Also, can you shed any light on what happens when a regular proton stream comes in, especially with the heavier ions present. I presume from the little I’ve read that the ozone layer takes an immediate hit but how much is reliably known about the chemistry that follows? The knock on effects seem like they could be very far reaching.
Set aside the science for a moment. The point of the press release wasn’t to add to anyone’s knowledge or understanding. It was a political tactic to preemptively discredit any hypotheses regarding the influence of the Sun on Earth’s climate. Thus, if/when the climate enters a long term cooling mode, they can say “Well, we’ve already shown it can’t be due to the Sun. Big mystery. But we better wreck the global economy because the planet is storing the heat somewhere.”
OT, anyone who can make a statement regarding the Heat being “stored” somewhere isn’t a scientist. They’re clowns.
Leif Svalgaard (02:35:37) :
Yet America [or more precisely USA] is also the place were an almost equal percentage believes that the Earth is only 6000 years old.
The difference being that those people cannot force their strange views onto the rest of the country (let alone the rest of the world), unlike warmists with their Cap’n’Trade legislation.
Bob Long (20:04:32) (Quoting Australia’s ABC’s “Lateline”): “So in the book we talk about how an anti-global warming blog called the What’s Up With That? actually won the award for “best science” blog, which was pretty outrageous…
…… Pfft, The ABC is outrageous, considering that the Australia’s ABC is a government funded propaganda organization that is 100% Labor party orientated and that the program “Lateline” has a host, Tony Jones who is a bolted on Socialist elite….. It is no wonder that they are critical of a privately owned and well run Science blog with good journalistic content like WUWT……
Leif,
“Yet America [or more precisely USA] is also the place were an almost equal percentage believes that the Earth is only 6000 years old.”
I wonder if it is these simple-minded people who are the reason we still have our freedom. It seems the more “scientific” and forward-thinking the society, the more likely they have fallen or will fall into bondage.
Lysenko is alive and well.
Mike
re, Leif (02:35:37:
“Yet America [or more precisely USA] is also the place were an almost equal percentage believes that the Earth is only 6000 years old.”
I can’t believe you said this Leif. Not only is it grossly wrong, it’s a stereotype spewed forth by many rabid warmers and extreme leftists.
Next time your in the USA, do an informal poll of your own. I bet you’ll find less than 1 out of 100 believes it.
What this says to me is that if the low activity of the sun, as measured by sunspots, has had anything to do with the lack of warming in the last few years, it doesn’t have to do with the Svensmark theory, which requires a lower solar wind to allow more cosmic rays to create more condensation nuclei.
Instead, if there has been any solar influence on the lack of warming the last few years, it much be through the mechanism proposed by Joanna Haigh: the 7% to 8% decrease of UV radiation at the minimum of the 11 year cycle causes less stratospheric ozone to be created, which through complex atmospheric processes causes a cooling. That effect was in fact just confirmed by the NOAA or NASA work using two different models.
That’s for the short term. What about a longer term period like the Maunder Minimum?
If the sun’s inactivity, marked by 70 years of very few sunspots, caused the Little Ice Age, what would the mechanism then be?
As Leif says, there is a strong solar wind leading up to every solar minimum (in the 11 year cycle), but it has now (finally) weakened. Suppose after weakening, the solar wind stays weak until sunspot numbers again ramp up? If this is the case, the possibility remains that over a long period such as the Maunder Minimum, the solar wind might indeed have been relatively weak for many decades. That would allow both the “Haigh effect” and the “Svensmark effect” to operate in tandem, and give us the Little Ice Age.
Leif, what do we know about the solar wind during the Maunder Minimum, if anything? It seems to me that the graphic from Judith Lean’s 1992 book for the NSF, the one showing Be10 and C14 isotopes as an indicator of solar activity, might provide backup for the “Svensmark effect” during that time, because clearly there were more cosmic rays creating increased levels of these isotopes during the Maunder Minimum.
I’m serious Leif — I really want your thoughts on this.
It would be beneficial if the impact of all these other solar variations could be fully explained.
We still have a Faint Young Sun paradox to explain. It is very likely that solar wind was much, much stronger in the distant past. It is likely that the Sun had a much stronger magnetic field and produced more x-ray and UV emissions in its early stages. There are even theories that the Sun lost more mass in its early evolution than the standard model indicates.
Generally, if these other changes can be shown to actually impact the climate, it might help explain why the early earth climate was warmer than it should have been.
Leif,
As I am relatively new to WUWT, you may have already answered these questions:
What is your position on how much of a role the sun has had in the climate change observed since the Industrial Revolution?
What role do you think human greenhouse gas emissions have had?
Leif Svalgaard (02:31:19) :
tallbloke (00:05:17) :
Are they coming out perpendicular to the solar surface in fairly narrow streams or is there sufficient ’spread’ that they still ‘cover’ the matter in the orbital plane?
Near the Sun the streams expand laterally to fill all of space, so there are no ‘empty’ spots. When there are few and weak low-latitude coronal holes, plasma from the polar regions is bent ‘down’ towards the equator. For details see:
http://www.leif.org/research/A%20View%20of%20Solar%20Magnetic%20Fields,%20the%20Solar%20Co
Fascinating. So would assymetry in ligher latitude coronal holes between northern and southern solar hemispheres influence the ‘flatness’ (notwithstanding the ‘waviness’) of the heliospheric current sheet? Would this mean planets might spend more time on one side of the sheet than the other as it sweeps round each 27 days, as an effect separate from (but adding to or subtracting from) their declination relative to the solar equatorial plane?
Complicated sentence – sorry.
I got a kick out of this story from a year ago
“Sun Shows Signs Of Life: Long-Awaited Solar Cycle 24 Starting To Take Off”
http://www.sciencedaily.com/releases/2008/11/081111230341.htm
ralph, I am a skeptic, and don’t buy some of the stuff that Leif is selling but “If the answer is yes, then these colder episodes were clearly linked to lower Sunspot activity, ” is just not a logical statement in any sense. It is rhetorical, and nobody every proved a scientific fact with rhetoric.
Richard111 (04:30:30) :
Duality of purpose. Pre-emptive strike borne out of sheer terror. The Sun today bears little resemblance to what it was at any time in 1996/97, therefore they have no clue as to what comes next.
When in doubt, stall for time.
Won’t do any good.
6 mos. from now the hole they now dig will be dug that much deeper.
gtrip (01:41:20) :
“We used to use God as a driver of mankind purpose. Now we use the earth as our driver. It seems we are taking a big step backwards.”
Interesting point you make. Been thinking about it all day
From: http://www.science27.com/Earth/index.htm
“According to the Danish physicist Henrik Svensmark (Danish National Space Center) the variation of Earth’s temperature is (in brief) caused by the intensity of the solar wind.
For the first time in history, we therefore have a serious common denominator that can explain both the variation of Earth’s temperature as well as the cause of the (real) dynamo of Earth’s magnetic field.”
Aligner (04:32:22) :
On Dec. 15, 2008 NASA anounced there was a burst of regular protons that was preceeded by a stream of intact hydrogen atoms. How common do you think these are and what effect do you think they may have on the atmosphere?
Rare [happens in connection with strong flares], and little or no effect as the flux of atoms is much smaller than the normal solar wind.
Also, can you shed any light on what happens when a regular proton stream comes in
They do not ‘come in’, as they cannot cross the Earth’s magnetic field, see my reply to anna upthread.
ralph (03:52:46) :
Do you believe that the Maunder and Dalton minimums were colder epochs?
Not specifically, rather, several centuries were cold and it is probably just a coincidence that there was low solar activity embedded in that period.
Leif: my appreciation for your time answering what are often the same questions over and again, and in providing links – you have great patience and dedication, I cannot imagine how you do this and have time for anything else!
And also, to America and WUWT, for commitment to truth and politely done too!
Leif – on the GCR since 1950 – the four major troughs during solar maxima show a deepening through cycles 20-22. If you assess the area in the trough as a measure of any (potential) cumulative impact, you will see trough 22 is about 35% greater than trough 20. There is then a 15% recovery during cycle 23.
I make the supposition (in ‘Chill: a reassessment of global warming theory’ – chapter on cosmic rays – for which I would be keen to get your feedback) that it is this cumulative effect that would be important if Svensmark’s theory is right and Usoskin’s confirmation of that with additional latitudinal effects toward the poles – and in this case, there would be cloud thinning in three pulses through cycles 20-22, leading to ocean surface warming and storage in the upper oceans – as registered by satellite data on radiation flux (short-wave at the surface), and upper ocean heat storage data (also reviewed in my book). The final consequence of this build up of heat – which is shuffled in the oceans into two major storage areas in the northern Pacific and northern Atlantic gyres with a few years lag, could have been the enhanced El Nino of 1998.
During cycle 23, the trough recovered by about 15% – and satellite data registers a step change in global cloud cover of about 2% during 2001, since maintained. This correlates to a flattening of the upper ocean heat storage (initially reported as a drop, but data since corrected), and of course, the current ‘cooling’ or flatline, as it may prove with the latest ENSO waxing strong.
Of course, these are all correlations – but it would be wrong to dismiss them, as indeed the European Space Agency acknowledge with their appointment of Svensmark to lead a $60m team of investigators at the CERN research centre who will look at potential mechanisms of cloud seeding.
There are other ways of affecting cloud cover – it can be changed spatially, without necessary altering global percentage cover, or even ocean basin percentage cover. And as the upper ocean heat stores are not distributed homogenously, the pattern of cloud above them become very significant.
In the north Atlantic gyre for example, a significant percentage of the warm water lies sufficiently far north for cloud insulation to be important during the northern winter. If cloud banks moved south by a couple of hundred kilometres, there could be an accelerated heat loss.
We know that each ocean basin has an oscillation linked to sea level pressure, and that this will be reflected in cloud cover and wind patterns – and also therefore, sea surface temperatures. I suspect the cool phases of both the PDO and NAO are determined by phase-shifts in cloud cover. I also suspect that the track of cyclones across these heat stores also shifts and that they are essentially heat extraction processes that have similar shifts – at some point extraction dominates over accumulation, and a major shift will occur when the excess heat is depleted.
The direction of the storm tracks is influenced by the jetstream – and it is known that the jetstream is sensitive to the magnetic status of the sun (mechanism not know – but may be linked to UV emission and solar maximum/minimum, which can be substantial variation of about 8%) – there may be other mechanisms that would influence the polar vortex and feedback to the jetstream. Research by Shindell at NASA concluded that during the Maunder Minimum the jetstream shifted southward (sediment data support this).
Let us suppose, theorise, that during a prolonged minimum, the ocean system moves into longer term depletion – over 50 years it would lose 0.5 C globally (equivalent to the whole of the global warming period 1950-2000), and that it might take some time to recover. We would have a mechanism for the 400/800 year cycles noted through the late Holocene, of which the last LIA trough was the deepest, and the recent warming one of the highest. How to falsify this hypothesis? – collect data on the historical track of the jetstream in relation to solar cycles and test for correlations; check upper ocean heat storage for correlation with cloud patterns; research mechanisms for solar factors affecting the polar vortex and feedback to the jetstream; analyse regional cloud data by cloud type and compare to GCR flux and other factors (though I suspect the jetstream effect to be dominant).
Until this work is done, I would argue it is unwise to dismiss solar-cloud or any solar-climate correlations (noting the importance of time-lags and feedbacks with ocean oscillations). By assuming random internal variability, climatologists have not sought to answer these questions. This is poor scientific practice.
A couple of questions, please:
1) I heard that the Earth’s magnetosphere has recently developed a large ‘hole’ – does this mean that plasma can come in?
2) Was the gamma ray burst of solar or galactic origin?
3) Was there anything unusual about the sun when the Carrington event occurred? How does the sun’s status then compare to today?
4) How does the magnetic field of a star transmit the mechanical energy of angular momentum from its satellites – as astrophysicists believe is the case (I have never understood how the gravitational force is actually transmitted and the whole orbital ‘rope’ anchored in the sun!).
Stephen Wilde:
I think the cloud effects, if real, would readily transmit to the oceans and create a signal, with some time-lags due to currents and storm track shifts.
@Kevin
“Sarah Gibson is cute. Therefore, I believe her analysis. Sorry scientists.”
You are right. She would be a good person for a little bit PR in TV for our cause.
I’m sure people prefer to see here instead of Joe Romm.
Any information if she is still single? 😉
Leif 2:31:19
The information stream is stopped about 10 amplifier radii away from the speakers. A complicated system of electric currents are induced and a complicated system of speaker parts movements results that eventually leads to visible shaking and aural disturbances.
And there’s a big fat logical fallacy sitting in your insinuations to Frank Lansner at 2:35:37. Can you find it?
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Scott 3:11:51
There is a much simpler explanation for why the ‘scientists’ aren’t getting their message across to the general public. It is because they lie, and their message is false.
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kim 7:03:00
Leif, there is a bitterness in tone in my comment about your’s to Frank, that I do not personally feel toward you. It is among the most hackneyed of the alarmists’ criticisms to equate climate skepticism with evolution skepticism. It is a fallacious charge, particularly since the CO2 true believers are becoming the new deniers, the new flat earthers. I’m just trying to keep you off that thin ice.
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How do those few electrons make all those people dance and spin? Well, I know for sure, CO2 is involved.
::grin::
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