Another anemic solar cycle 23 sunspeck, could 19th century astronomers have seen it?
From Spaceweather.com
SUNSPOT 1016: A ring-shaped sunspot numbered 1016 has emerged near the sun’s equator. Its magnetic polarity identifies it as a member of old Solar Cycle 23. Until these old cycle sunspots go away, the next solar cycle will remain in abeyance.
Doubtful that they would have seen the spot, but it does not change the fact that the sun has been very, very quiet. More of a records and numbers thing for those of us watching. Do we have history in the making, more than likely, but so far our government has not figured out how to tax the event so they stay with AGW.
A thought about defining the minimum.
The sunspots that got counted this year in some cases lasted less than 24h but still got a count and even a 2 day duration count.
If we have a sunspot that last for less than 24h and it overlaps 2 days it could get a duration of 2 days. If it would fit perfectly in a calender day it might get only a 1 day count.
Isn’t there a great risk of getting an inaccurate definition of a solarminum when shortlived sunspot count could vary with up to 100% depending on which hour on the day it starts and ends?
At what point would this solar cycle (if the solar inactivity continues at this level) become something extraordinary?
I propose a test…we should try to replicate as accurately as possible the methods by which the 16th, 17th, 18th, and 19th astronomers would have used to determine the existence of a sunspot. The data collected should then be used to calculate a “sunspot sensitivity” number by which we can attempt to ascertain the intensity of the sunspot these pioneers in the field of solar astronomy could actually resolve.
just a suggestion………
They would have seen the spot(s). Yesterday there was more than one. It was a little cluster of spots, much like a pubescent teenager’s forehead. The spots would have been just ho hum stuff if cycle 24 had begun (cycles overlap by many, many months). The fact that this cluster of spots has occurred in the absence of cycle 24 polarity spots is interesting. So it looks to me like cycle 23 is just being normal. Cycle 24 not so much. But let’s be clear, the Sun is not cooler for lack of spots.
Just a query, and I have no expertise on Solar Physics. Since SC23 has been mostly “over” a couple of years back and we have had some SC24 spots. Is there any possibility that this spot is SC25? I was thinking of the analogy of a human heart, each heartbeat being a regular cycle, when a heart goes into fibrillation the cycle is weak and “fluttery”.
During a Solar Minimum could we lose the average 11 year cycle and what we are seeing is a fibrillating sun with many rapid weak cycles?
Watching the Sun spot up and the Catlin team freeze up is a bit like watching grass grow.
What if the few cycle 24 spots were all we get and what’s being called remnant cycle 23 spots are cycle 25?
well, sunspots or not, cooling or not, here we go using a red herring to chase another red herring…..the Montreal protocol was an abomination. now, since we can’t pass cap-and-tax, we will use the Montreal tax-us-all to fight non-existent AGW. maybe, with enough data, we can prevent one bad boondoggle and repeal another….
Obama Administration to Push For Major Initiative to Fight Global Warming
http://www.foxnews.com/politics/2009/04/30/obama-administration-push-major-inititative-fight-global-warming/
UNITED NATIONS — The Obama administration, in a major environmental policy shift, is leaning toward asking 195 nations that ratified the U.N. ozone treaty to enact mandatory reductions in hydrofluorocarbons, according to U.S. officials and documents obtained by The Associated Press.
“We’re considering this as an option,” Environmental Protection Agency spokeswoman Adora Andy said Wednesday, emphasizing that while a final decision has not been made it was accurate to describe this as the administration’s “preferred option.”
The change — the first U.S.-proposed mandatory global cut in greenhouse gases — would transform the ozone treaty into a strong tool for fighting global warming.
“Now it’s going to be a climate treaty, with no ozone-depleting materials, if this goes forward,” an EPA technical expert said Wednesday, speaking on condition of anonymity because a final decision is pending.
The expert said the 21-year-old ozone treaty known as the Montreal Protocol created virtually the entire market for hydrofluorocarbons, or HFCs, so including them in the treaty would take care of a problem of its own making.
I think it’s about time we all stand up and put an end to this eco-fascism before it destroys all of our liberties.
Aggie,
There actually is a corrective constant for “observatory factor” in the calculation for relative sunspot number. I believe that this was the formula (see below) invented by Wolf (1816-1893), the “Father” of Sunspot counts. With disciplined parameterization, that could compensate for improved instrumentation.
However, I reckon that the discipline was elusive. 😉
The relative sunspot number is computed using the formula (collected as a daily index of sunspot activity):
R=k(10g-s)
where R is the relative sunspot number, s is the number of individual spots, g is the number of sunspot groups, and k is a factor that varies with location and instrumentation (also know as the observatory factor).
I believe this is the reference for that:
http://www.ngdc.noaa.gov/stp/SOLAR/ftpsunspotnumber.html#international
…and with all due respect, Hook ’em Horns!
After months of research I have replicated how early astronomers would have viewed the sun. I propose that this method is the most accurate way to determine if a spot/spec should be counted.
From a distance of 3 feet view this image on your computer monitor, but for no more than a single second (you don’t want to burn your eyes!). If you can clearly see a spot, then it counts.
http://umbra.nascom.nasa.gov/images/latest_mdi_igram_thumbnail.gif
Perhaps we can get someone to host this image on a blog.
Trevor, new cycle spots always start at high latitudes. This is 23.
Cycle 23 is like the Energizer Bunny, it just keeps going and going and going, going, going, going, going, and going.
If the Sun really can affect Earth’s climate via affecting the SST’s we may see some rather cool oceans with the next La Nina comes around, considering SST’s have been dropping steadily since 2003.
WestHoustonGeo (18:08:27) :
Well, Mr. Horn, I think you miss my point 🙂
I was suggesting that the detection methods be compared, not the observed values. Using true-to-period replications of the types of equipment used, I was hoping to obtain correlations between the different types of equipment and observed sunspot values for each century. With all due respect and given your educational institution, I can understand how you missed my meaning 🙂
Gig ‘Em!
Whoop!
Last March three spots went by shouting the cry that cycle 23 still ruled. Now over a year later we have a SC23 region with several spots, putting most of the regions (specks) we’ve seen from cycle 24 to shame. Notably, from Febuary of this year, no cycle 24 region has reach a sunspot number of 15, but this region has. Where are your spots, cycle 24?
Sunspot numbers from:
http://www.solen.info/solar/
What is most important is that the sunspot was from cycle 23, which will be 13 years long now in May. The last cycle this long was in the 1790s, predating the Dalton Minimum. Cycle 24’s first sunspot was January 2008 and it has had very few spots. So a very long cycle 23, and an almost non existant cycle 24, bodes for a very cool 30 year period coming before us.
I nearly didn’t read this piece, because I don’t like Star Trek.
The spot did run away! It’s not visable in the latest SOHO image. Time to start another long spotless streak?
Trevor: No. The cycles last an average of 11 years. They have lasted as little as 9 years as well as longer than 13. I think there was a period where there were no sunspots during the Maunder Minimum, so one cycle was skipped, but that quiet period lasted over a decade.
The sun spots appear at the poles early in the cycle. The latitude at which they appear gradually decreases over the years until they only grow near the equator. There is no way that we can have a Solar Cycle 25 spot yet.
John M Reynolds
Global temperatures continue to run well above average and the sun remains quite. How much longer before we are willing to admit that this is entirely consistent with the enhanced greenhouse effect?
PS Awfully hot in Alaska ATM – http://www.wunderground.com/US/AK/Fairbanks.html . Perhaps worth a report?
NOAA counted 15 sunspots today:
http://www2.nict.go.jp/y/y223/sept/swcenter/sunspot.html
Looking forward to global warming update for April, what’s it going to be? Hottest April ever? Arctic to be ice free by June? Massive swing up in CO2 levels?
And isn’t that the real question. In order to have consistent data, I am surprised someone doesn’t have a reproduction instrument and see what spots can be observed.
We will never be 100%, but as with the hurricanes, the observation method is as important as the observed.
…..I saw a little black spot on the sun today!…… We are all going to be freezing are asses off for the next century!…..
My apologies to Sting and his music….
WestHoustonGeo (18:08:27) :k is a factor that varies with location and instrumentation
To be fair then “k” should be equalled to “0” 🙂
DJ (18:47:47) :
Thank you for the report on your planet, DJ. Tell me, what color is the sky there?
DJ-
1. 2009 is running cooler than every year since 2001, aside from 2008. STILL, no sign of global warming kicking in, so no…not consistent with popular notions of AGW/CO2 forcing.
2. Yes, Fairbanks is quite warm right now. They were due after 6+ months of well below normal temps in Alaska.
RE:
Pearland Aggie (18:03:56) :
“….
UNITED NATIONS — The Obama administration, in a major environmental policy shift, is leaning toward asking 195 nations that ratified the U.N. ozone treaty to enact mandatory reductions in hydrofluorocarbons, according to U.S. officials and documents obtained by The Associated Press.
“We’re considering this as an option,” Environmental Protection Agency spokeswoman Adora Andy said Wednesday, emphasizing that while a final decision has not been made it was accurate to describe this as the administration’s “preferred option.”….”
This is no doubt a prelude for the administration to harness EPA to the UN as the “environmental” governing body with respect to AGW.
They just keep coming– the solar cycle 23 spots. You must admit this one looks more impressive than anything coming from 24. Yesterday there was a cluster.
George, your wish is my command: http://whatcatastrophe.com/drupal/node/25
DJ (18:47:47) :
Global temperatures continue to run well above average and the sun remains quite. How much longer before we are willing to admit that this is entirely consistent with the enhanced greenhouse effect?
PS Awfully hot in Alaska ATM – http://www.wunderground.com/US/AK/Fairbanks.html . Perhaps worth a report?
And the temps in Australia/Nw Zealand?
I’ve asked this question before but never seen an answer.
In what year was an instrument invented that would have been able to see the most recent spot (1016, was it?)?
DJ(18:47:47)
Sorry DJ, high temperatures this time of year in Interior Alaska are not all that uncommon. I have been keeping track of weather in my yard for over 20 years, here in Fairbanks, and in 1994, 1995, 2003, 2004, and 2005, (just to name a few) we had temps in the mid to high 70’s on dates April 26 to May 1.
I still use these sunspot images to find specs on my LCD.
So far 5 specs, no sunspots.
Answering this question really isn’t very hard. All we need to is go to museums that have saved the tools that were used to count sunspots through history, make reasonable replicas of them and then take them out the next time there’s one of these specs and see what you see. Can we figure out what the sunspot measurement tool was in say 1613, 1713, 1813 and 1913? I’ll go first.
It seems that multiple people began observing sunspots in 1610/1611, including Galileo:
http://galileo.rice.edu/sci/observations/sunspots.html ,
here is a time line:
http://galileo.rice.edu/chron/galileo.html
and this is when our modern sunspot number tracking began: http://en.wikipedia.org/wiki/File:Sunspot_Numbers.png
Here’s some of the pictures of sunspots that Galileo drew: http://galileo.rice.edu/sci/observations/sunspot_drawings.html
and here are some of his writings on sunspots in 1613.
http://hsci.ou.edu/exhibits/exhibit.php?exbgrp=1&exbid=13&exbpg=2
One of the telescopes that Galileo used can usually be found in a museum in Florence:
http://joetourist.ca/Italy/FlorenceScienceHistory.htm , but it just so happens that its currently on loan, to the Franklin Institute in Philadelphia right now:
http://www.google.com/hostednews/ap/article/ALeqM5hZjQkA9hNcjEjaBvmKQNr1Zp3zBgD97AISR80
A team in Florence has actually recently recreated one of Galileo’s telescopes:
http://www.scientificblogging.com/news_releases/galileos_telescope_recreated
Perhaps we can ask to borrow the replica telescope in Florence to conduct a study or ask them for detailed instructions so that we can recreate our own? Is there someone, with a scientific background, who is interested in taking this on as a project?
Here’s something, a ‘reduce CO2 to save the planet’ game, centered around Green Propaganda
http://www.gamespot.com/pc/strategy/ecotycoonprojectgreen/index.html
Not to mention I found it as the comic ‘Sherman’s Lagoon’ was doing a week telling people about the melting Arctic and illustrating it as virtually Ice Free which it really was not quite last year and definate not this year.
Who can afford enough servants?
DJ (18:47:47) :
Global temperatures continue to run well above average and the sun remains quite. How much longer before we are willing to admit that this is entirely consistent with the enhanced greenhouse effect?
PS Awfully hot in Alaska ATM – http://www.wunderground.com/US/AK/Fairbanks.html . Perhaps worth a report?
In the weather isn’t climate mode after the last 2 years we will take all the
the global warming we can get. Since Jan 2008 Fairbanks is running about 1.4 below what the National weather service says is normal. Anchorage is -1.6 as of today. I love today’s weather, in the 50’s, short sleeve weather, as I look out my front window at a snow covered mountain and studiously ignoring the ice still on my favorite trout lakes.
All that’s left is a bright plage region, so this one lasted all of two days. A bit better than last week’s quicky from the 21st.
Forget climate change; give some big research bucks to the solar guys so they can get a handle on what’s not happening.
Pearland Aggie (18:03:56) wrote: “… here we go using a red herring to chase another red herring…..the Montreal protocol was an abomination. …”
Two immediate thoughts.
1. That this is a warning bell we would do well to heed and respond to.
2. That it is an indication of concern amongst the AGW promoters that not all is going to plan.
Leading to: This move must be watched carefully and broadcast widely. If “they” are feeling cornered their present level of extremes will be exceeded. This could lead to “their” implosion; but it could also lead to even greater damage to the world at large than “they” are threatening now.
The cornered rat…
Larry Sheldon (19:58:06) :
I’ve asked this question before but never seen an answer.
In what year was an instrument invented that would have been able to see the most recent spot (1016, was it?)?
Mt. Wilson’s 12″ F150 apochromat was somewhere around 1912.
One hundred years ago, 1909, 11016 could not be projected sucessfully.
I tried with a conventional similar to Wolf’s, and could not see the spot. It was far too faint.
I have sucessfully followed all the main spots from 2008 until late January. From then on, the spots are too faint to project with my instrument.
To answer the topic question: “Another anemic solar cycle 23 sunspeck, could 19th century astronomers have seen it?” the answer is……..
NO.
Today, April 30, Mt. Wilson saw the main spot, but has a question mark. Means to me that attendant microspots in the group were not clearly discerned.
And this is why Catania sees more:
Ha Lyot-filter (bandwidth of 0.25 – 0.50 Å, tunable filter range +/- 16 Å)
and a 1360 x 1200 Astromed TE4 CCD array. In patrol full-disk mode
the camera can taken images every 60 s, with a dynamical range of 16 bit.
It is CCD aided ?? You tell me what they are doing.
Says to me that they have machined aided drawing cheater bar.
Technically sophisticated, yes, historically accurate in this topic’s context, no.
And no surpise, then, that Catania sees both the main spot and a subspot in the group today, while Mt. Wilson’s 12″ F150 Perkin-Elmer apochromat only got the main spot undera a seeing of 3.
Catania only has a 6″ F/15.6 refractor ( probably an apochromat of advanced design).
Compare the instruments and the results for yourself.
I enjoy your blog. I have never posted here but I thought you might enjoy this some what off topic link.
http://forums.catholic.com/showthread.php?t=334268
You may have to scroll down a bit to read the question and the answer.
Flood Watch in effect through Saturday morning for the Tanana river in Salcha…
Ice jam Flood Warning has been cancelled for the Chatanika river…
Near record high temperatures through Friday…
In any year that I have found an abundance of record temps, they occur at both ends of the spectrum, record heat and record cold. The sine wave gets stretched both ways, preserving the median temperature. When the year is over, you take the whole record & examine it.
Which won out, record heat or record cold? What was the median temp?
Answer that and you answer the climate question for that particular year.
Leon Brozyna (21:00:19) :
Forget climate change; give some big research bucks to the solar guys so they can get a handle on what’s not happening.
Agreed. Hand PolyAnnaScience the pink slip. Even the most diehard Disaster Movie enthusiast tires of the same old flickers. Who’s up for Earthquake IV? Asteroid VI?
Pam says, “But let’s be clear, the Sun is not cooler for lack of spots.”
Which makes me ask, “What temp are you measuring? The average surface temp? The average volume temp?” It’s just one big ball of gas – nothing solid or liquid – just fuzzy stuff.
Are you saying that only the surface temp can affect the Earth? Or, is there some temp probe used to measure the internal temp of the sun? I’m guessing any temps are just theoretically calculated and not exactly measured.
There are about 3 things that drive me completely out of my mind – one is a marital thing, one deals with lib media, and the other one is the claim that the sun can’t drive Earth’s temp chages. AAAAHHHHHHHHH!!!!!!!
DJ (18:47:47) : “Global temperatures continue to run well above average and the sun remains quite….”
Quite? Quite what? Quite sun-like? Or quite like the marquee down at your old Bijou Theater? In case no one’s told you, DJ, the marquee switch is in that little panel above the popcorn machine.
Since late 2007 its been cooler, as compared to the previous few years. During this period we have had both la nina conditions (or more recently ‘la nina like’), and very low sun activity. So which caused the cooling? Or is it a bit of both?
Well a good test may be coming up. Nino 3.4 just crossed over to the warm side of zero a couple weeks ago, and it appears a reasonable chance that conditions will swing further towards el nino in coming months.
It can take a few months for temperature to follow ENSO, so assuming that ENSO conditions do continue towards el nino (very difficult to predict for sure), then us alarmists will no longer be able to point towards the recent La nina/cool ENSO conditions to excuse any further cooling.
At the same time I notice that Uah daily values have just nudged high enough to be greater than same day any year from 1999 to 2007 (but presumably lower than 1998 which was very high, but the uah site doesn’t display daily values for)….
I see another 23 forming center, a bit above the equator.
Pretty soon I will start telling fortunes.
The question of whether the sunspot number two hundred years ago was accurately determined has been solved 150 years ago. Solar activity creates more ultraviolet light that in turn creates and maintains the Earth’s ionosphere during the daytime as an electrical conducting layer(s). During the day the ionosphere heats up and thermal winds blow this electrical conductor across the Earth magnetic field which causes an electrical current to be induced. An electrical current as its own magnetic field and as the Earth rotates under this current [which is fixed under the Sun] an observer on the surface will see a compass needle be deflected about a 1/5th of a degree to one side in the morning and then returning to its normal position when night falls. This diurnal variation was discovered by George Graham in London in 1722 and was studied by several workers in the 1740s, 1760s, and from 1780 on to the present day. Back then, 1/5th of a degree could be readily measured and we have thus reliable data about the deflection of the ‘magnetic needle’ since the middle of the 18th century. It turns out the amount of deflection is a sensitive measure of the Extreme UV flux from the Sun, we therefore know what the EUV flux has been the past ~250 years. Modern data shows that the sunspot number [until now] is a good proxy for the EUV flux, so if we know one, we know the other. We therefore know what the ‘real’ sunspot has been the past 250 years. By comparing the numbers reported by a given observer [over some time] to what we know they should have been we can determine the ‘correction’ factor [the ‘k’ in the equation SSN = k * (10*g+s)] for that observer. It therefore does not matter how good his telescope was or his eyesight or if he only counted big spots or included the specks, or whatever other quirks there might be. We can determine what his count would have been had he used modern instruments and techniques.
This much was already known to Rudolf Wolf in 1859, who used this technique in his inter-calibration of different observers to produce his famous composite Wolf Number. Later observers had forgotten or had come to distrust the method using the magnetic needle [basically the ‘fault’ of the famous geophysicist Sidney Chapman who pointed out that relation Wolf had found between the sunspot number and the diurnal variation of the Declination – the angle between true North and the direction in which the compass needle pointed varied from station to station and with time such as to render the method suspect]. As a result the sunspot number calibration since then has changed when the primary observer changed without anybody noticing.
With our modern understanding of how the ionosphere is created and maintained we now know that the important parameter is not the Declination as Wolf thought [and as Chapman derided], but the additional magnetic force in the East-West direction created by the stationary ionospheric currents overhead as the observer rotates with the Earth. There is a simple relation between the East-West force and the Declination [F = H cos D], so one can readily compute one from the other, which means that the geomagnetic method becomes correct and useful if one uses the East-West deflection instead.
The result of all this is that there is a reliable way of gauging solar activity [e.g. as measured by the EUV] going back 250 years. And that we can then determine the calibration of the sunspot number from that.
There is one fly in the ointment: the sunspot number may not be a good proxy for solar activity at all times. Livingston and Penn have found that in the last decade sunspots have become harder and harder to see [and in fact predict them to become invisible by 2015]. The magnetic field of the spots [albeit a bit weaker] will still be there, the solar cycle will still operate, cosmic rays will still be modulted, 10Be in ice cores will still vary, there will still be an interplanetary magnetic field, there will still be a solar wind, comet tails will still point away from the sun, there will still be aurorae, and magnetic storms, and flares, and CMEs, etc [all possibly slightly subdued]. This means that the sunspot number will no longer be a good measure of solar activity. Perjaps this happened during the Maunder Minimum, as well. At the ongoing Space Weather Workshop, Ken Tapping, who measures the 10.7 cm radio flux from the sun, that in the past was an accurate proxy for the sunspot number [actually the other way around], has just presented this paper:
Title: The Changing Relationship Between Sunspot Number and F10.7
Abstract: Sunspot Number and the 10.7cm solar radio flux are the most widely-used indices of solar activity. Despite their differing nature and origins at different places in the Sun, these two indices are highly-correlated to the point where one can be used as a proxy for the other. However, during Solar Activity Cycle 23 we started to see a small but definite change in this relationship….
—–
This may be an indication that L&P are correct [or at least some change is happening], but it is still to early to tell. The coming cycle will be most interesting if these things are happening.
It also means that prediction of the sunspot number becomes a bit fuzzy. What almost all methods predict is the magnetic field expressed by the sunspot number proxy. The implicit assumption is, of course, that that relation does not change with time. If it does, the predictions will be of the ‘effective’ sunspot number [i.e. the ‘old’ number that such and such magnetic field would give].
All of this is somewhat speculative, but makes the coming cycle extremely important for our understanding of the cycle.
Leif Svalgaard (22:37:52)
Thank you Dr. Svalgaard for a most enthralling exposition.
I remember as a child visiting the Franklin Institute in Philadelphia. While I have no idea if it is still there, one of the exhibits was a solar observatory that projected an image of the sun from a telescope onto a white screen which appeared to be about like the stuff that artist’s canvas is made of. The image of the Sun seemed to be about three to four feet in diameter and I remember spots being clearly visible at the time. This would have been some time in the 1970’s.
Leif 22:37:52
Thanks for that bulletin. That ties a lot of things together. Marvelous. How’s that for a label, Anthony? And thank you, Anthony and moderators. It’s easy to support such a great team.
=============================================
This must be it. So on a day when there is one of these “specks”, maybe a reader in Philadelphia can go down there and see if they can see it at the solar observatory there. The equipment there would be comparable, I think, to what was available to scientists going back 100 to possibly 150 years. That is, unless they have replaced it with a downloaded image from a satellite now.
I have emailed Dr. Tony Phillips over at spaceweather.com three times now asking exactly these questions concerning instruments and methods used in the early 1900’s and how they compare to those used today. I specifically asked about the spot that broke the 22 spotless day run and minute spots over the past couple of weeks and whether or not those would have been visible in 1913. I have yet to get any response at all. I agree that a side by side comparison using old and new technology should be done.
BUT Leif Svalgaard (22:37:52) :
How many spots “should” there have been (April 2009) using 10.7cm or 1/5 flux of the magnetic…..
can you “show” us the invisible spots/specks with these methods?
And please refrain from the should is a weasel word analogy.
Thank you from a cantankerous old man! 🙂
I have to admit, I am perversely enjoying these Sun news and projected colder period. Some folks would deserve to be tarred and feathered, though. At the end, I love cold and snowy winters. For me, repeat of 1907 Damon minimum would be very welcomed!
Fluffy Clouds (Tim L) (23:43:27) :
How many spots “should” there have been (April 2009) using 10.7cm or 1/5 flux of the magnetic…..
can you “show” us the invisible spots/specks with these methods?
The relation between F10.7 and sunspot number is not from day to day, but more like from month to month, or even year to year. The standard relation between the two is
F10.7 = 63.74 + 0.727*SSN + 0.000895*SSN**2
which you can then solve for SSN, given that F10.7 right now is 70.5 flux units. From that you calculate SSN = 9.2, but as Tapping points out the standard relation may not be working anymore.
And please refrain from the ‘should’ is a weasel word analogy.
‘should’ is not a weasel word in science. Given a formula y = 10*x + 5, y ‘should’ be 25 for x = 2. ‘Should’ simply expresses that if the relationship holds then such and such value is expected. At least that is the meaning I attached to my usage of that word in my posting. “Words mean what I say they do, Humpty Dumpty declared. No more, and no less.”
I think that what Leif is saying is that (a) each observer needs to be treated differently. Consequently, given a specific small spot, you can’t say that it was invisible in 1900. Different observers have different capabilities. (b) Even if you did pick a particular observer, you really don’t know whether or not they could see that particular small spot. Maybe there would have been bad weather that day. (c) What you end up with is a statistical relationship between spots seen now and spots seen then. And finally, (d), don’t worry, the experts have spent far more time than the vast majority of us amateurs or dilettantes, and have taken care of these things.
In any case, we’re seeing very little sunspots and cycle 23 is lasting a very long time.
The thing I’d like to know is whether or not the sunspots stay in sync over longer time when they go through a period of complete inactivity. What I’m asking is “is there some sort of time keeping that goes on even when the spots are invisible”. From the deviation between F10.7 and number of sunspots, and the decreasing visibility of spots, I suspect that there is a long term continuity to the things. Too bad they couldn’t detect polarity 200 years ago.
After that, I’d be interested in what the Fourier transform of the sunspot cycles look like. I suspect that if I looked around, I’d find an article or two on this. But what I’d really like is more exact timing information. What is the point on a cycle that is steadiest, and what are the characteristics of that part of the cycle?
thanks for the formula…. now to plug it into the data!!! vs versa
F10.7 = 63.74 + 0.727*SSN + 0.000895*SSN**2
which you can then solve for SSN, given that F10.7 right now is 70.5 flux units. From that you calculate SSN = 9.2, but as Tapping points out the standard relation may not be working anymore.
>Until these old cycle sunspots go away, the next solar cycle will remain in abeyance.
Is there any scientific support for this theory, or are you just being creative here? My understanding was that the underlying process for each cycle was very weakly coupled, and each new cycle starts to form several years before it’s first spot is seen – not long after the peak of the previous cycle has passed. Cycle 23 is just twitching – maybe the emergence of 24 in anger will sweep up the remains, but that is all.
carlbrannen (00:20:06) :
After that, I’d be interested in what the Fourier transform of the sunspot cycles look like.
It looks like this:
http://www.leif.org/research/FFT-Power-Spectrum-SSN-1700-2008.png
Note that there are many curves. Since the sunspot cycle observations do not extend infinitely long in time there are going to be ‘end-effects’. We can get a handle of how disturbing they are by computing the FFT over the full interval, then over the full interval minus one year, then minus two years, etc [up to 20 years for this example]
@ Robert Bateman:
Catania uses an Ha filter and CCD camera to take daily HA images of the sun.
http://web.ct.astro.it/sun/solec.jpg
They do a projection of the sun to determine the SSN. Its impossible to use an HA filter and do a sunspot count.
Btw, sunspecks also get count during maximum. We see them, so we should count them. Everything you observe should be logged.
Leif Svalgaard (22:37:52) :
The question of whether the sunspot number two hundred years ago…
Thanks for the knowledgeable and complete answer. Your expertise is astonishing.
Anthony; I feel it would serve a useful purpose for the post by Leif Svalgaard (22:37:52) to be made available in “Resources” so that each time sunspots become a topic a poster can point to it when others begin reinventing the wheel.
Aside from the fact that it will save Leif’s (always so graciously given) time, it will cut a lot of chaff from such threads ─ and prevent some of us from making fools of ourselves with a new enlightenment we just have to thrust upon a world-in-waiting…
DJ: According to some sources, temp lags by +-7 years. Solar activity peaked in 1990, temps peaked in 1998, so this quiet of 08/09 should technically be felt on earth in +-2015/16; according to some.
As far as I can tell, this cycle 23 spots outweigh cycle 24 spots for april, so surely minimum can’t be established yet.
DJ (18:47:47) :
Global temperatures continue to run well above average and the sun remains quite. How much longer before we are willing to admit that this is entirely consistent with the enhanced greenhouse effect?
This is a common error of thinking, that the momentaneous state of the Sun determines the momentaneous state of the planet. In fact, it’s the accumulated effect over time. Solar activity has been below average for the last 5-6 years, maybe longer. As a result the amount of heat received and stored in the Earth system has been decreased (through direct and, more importantly, indirect effects, such as cloud cover) and the accumulated effect of that over a long period, 10-15 years perhaps will drive the temperature down.
It has been estimated that the excess heat accumulated over the previous 30-40 years due to high Solar activity has now shrunk by 30-40% and is rapidly going down.
Thus, it can be expected that with continued low Solar activity in about 5 years we’ll be back at where the system was in 1950, and go downwards from there. If Solar activity picks up again, we’d see the effects 5-10 years later.
So it’s just the lag in the system, and no evidence whatsoever for the GH effect.
Something strange from the Independent
http://news.independentminds.livejournal.com/2281641.html
Full article
http://www.independent.co.uk/news/science/the-missing-sunspots-is-this-the-big-chill-1674630.html
Unless you have very good telescope optics and good “seeing” (i.e. seeing=disturbance in image quality due to local air turbulence) such specs are not visible at all.
This spot was slightly larger than some of the others we have (not) seen the last 6 months, so maybe it may have been noted by good observers in favourable locations. The ones in late March and early April would not have been seen by anyone on the ground.
Gerry (18:50:16) :
NOAA counted 15 sunspots today:
http://www2.nict.go.jp/y/y223/sept/swcenter/sunspot.html
More precisely, the sunspot number was 15. It was one group (10) with 5 spots, 10+5=15
Leif Svalgaard (22:37:52)
Thank you Dr. Leif Svalgaard
Carsten Arnholm, Norway (02:31:32) :
I agree. And you have to be projecting near zenith for such faint fuzzies.
carlbrannen (00:20:06) :
I think that what Leif is saying is that (a) each observer needs to be treated differently. Consequently, given a specific small spot, you can’t say that it was invisible in 1900.
I can, I have, and I will continue to say so.
If you are not an experienced observer, and are unaware of the the tremendous handicap offered by ccd detection, you have no idea.
To know before even beginning a task that there are X number of spots, the mind is pre-biased and determined to make the known outcome detected at the drawing.
We all know what happens to students caught cheating on an exam.
The test is invalid as far as the teacher is concerned, and so is the grade thereby given: Fail.
So too are spots purported to be observed that are in fact pre-biased towards detection by technological handicap.
M White (02:31:31) :
It is very tempting to use the sun as a public relations battering ram to counteract AGW. It is something the media can “understand” and probagete.
I think as skeptics we have to be skeptical of this too, i.e. a strong correlation of current sun condition to global temperature, until it is a proven fact.
Firstly because the correlation is not proven, it could be fortuitous that the Maunder minimum had low solar activity, and secondly there is fifty fifty chance that cycle 24 will pick up soon and we will be left with creme on our face, similar to the one the AGW have, though they still have to realize it.
Re: Leif Svalgaard (22:37:52) :
Wow, what a tour de force. When this guy finally flips to our side, look out warmists!
Leif Svalgaard (22:37:52) :
Thanks for detailed account. Very useful reference.
Some of you may have not opportunity to see actual records enumeration of sunspots during critical period of Maunder minimum. So here it is:
http://www.geocities.com/vukcevicu/MaunderSSN.gif
[i]Leif Svalgaard (22:37:52) :
This may be an indication that L&P are correct [or at least some change is happening], but it is still to early to tell. The coming cycle will be most interesting if these things are happening.[/i]
This may be, in Dr. Svalgaard’s words, entirely baseless and unfounded speculation, but falling Polar Field strength as measured at Wilcox SO
http://www.geocities.com/vukcevicu/L-P-project.gif
may be (just a speculation !) an indication what may follow.
Since Drs. Livingstone & Penn have no theory to explain the phenomena, I certainly can’t improve on that, but have added the comment as a purely personal observation.
Gerry (18:50:16) :
The sunspot number is not the number of sunspots.
Agree with those who question the counting of spots that only can be seen with modern telescopes generally placed on mountains. Europe, where most of the 17-19th century telescopes were located, is not noted for its continuous clear sunny days.
The best technical presentation I’ve come across of historical sunspots, how suspots are measured, and all the variations around the measurements and calculations is the article:
Dances with Wolf’s: A Short History of Sunspot Indices
Contributed by Carl E. Feehrer (FEEC)
Revised August 2000
http://www.aavso.org/observing/programs/solar/dances.shtm
He also disussses the benefits and problems with the 4 major indicies:
Wolf
(R) Zurich
(Rz) International
(Ri) American (Ra)
Best article on this subject that I’ve come across.
Since sunspots are crude surrogates for solar activity, modern solar instruments that measure total solar irradiance, mass ejections, and all other electromagnetic activities will, over extended time, replace this highly subjective measurement.
DJ asks: How much longer before we are willing to admit that this is entirely consistent with the enhanced greenhouse effect?
First you need to tell us what WOULDN’T be consistent with the “enhanced greenhouse effect”.
Agree with those who question the counting of spots that only can be seen with modern telescopes generally placed on mountains. Europe, where most of the 17-19th century telescopes were located, is not noted for its continuous clear sunny days.
The best technical presentation I’ve come across of historical sunspots, and how sunspots are measured, with all the variations around the measurements and calculations is the article:
Dances with Wolf’s: A Short History of Sunspot Indices
Contributed by Carl E. Feehrer (FEEC)
Revised August 2000
http://www.aavso.org/observing/programs/solar/dances.shtm
He also discusses the benefits and problems with the 4 major indices: Wolf, (R) Zurich, (Rz) International, (Ri) American (Ra).
Best article on this subject that I’ve come across.
Since sunspots are crude surrogates for solar activity, modern solar instruments that measure total solar irradiance, mass ejections, and all other electromagnetic activities will, over extended time, replace this highly subjective measurement.
Future generations will be puzzled with our intense divination of them for our use in solar predictions as we are with the Romans divination and prophecy using flights of birds (augary).
DJ (18:47:47) :
“PS Awfully hot in Alaska ATM – http://www.wunderground.com/US/AK/Fairbanks.html”
Awfully cold in northern Russia
http://www.wunderground.com/global/stations/23022.html
Whats your point?
Adam from Kansas (18:22:47)
The current state of space weather, and how the cycle is developing, favors an El Nino this year, and not La Nina. Even 2010-11 seems to look this way. But I would rather wait until early next year to make that official forecast, because of how fickle this transition period has been.
anna v 03:59:24 and
Leif 22:37:52
The interesting and instructive thing to watch, if sunspots disappear and other known manifestations of the solar dynamo continue, is if the earth cools and with what kind of lag. Of course, lacking a causative mechanism, even this won’t be definitive proof that the sun directs climate, but the correlated phenomena may well give a big clue to a linking mechanism.
One question I have, given our present ability to observe and measure, is whether or not the effects of a large volcanic explosion, or series of them, can be distinguished from whatever subtle effects a spotless sun might show. Are the various causes of varying albedo, if albedo be the means through which the mechanism acts, sufficiently distinguishable from each other?
====================================
Robert Bateman (03:25:18) :
I agree. And you have to be projecting near zenith for such faint fuzzies.
At 60N where I am the sun is rarely near zenith….
What I love about this odd solar cycle is the many new questions it raises. When so little is known about the sun, admittedly, they still use it as a constant in their superficial calculations and predictions. SURPRISE!
I hope it confounds the consensus scientists, the sycophantic politicians AND the Henny Penny public.
The scariest thing is that Obama seems to have a defunct truth/bs meter. I guess that comes from being a post modern liberal. WUWT helps us keep out own truth meters tuned.
Anecdotal:
Spring is late in Greece. About 20 days to a month. The winter was normal to mild, in my region, but April much cooler than average. I do not remember real heating needed in April , as happened the past month.
Swallows were about a month late in coming, middle of April instead end of March. Ants have not started walking around. Saw the first ant trail today. It means that seeds are late in coming, which is the result of lower temperatures than usual. Insect population is still low, no need for screens.
There has been snow at the 1000 meter height on mountains today.
M White (02:31:31)
anna v (03:59:24)
OK, Anna – but Hooray for The Independent having published the article by Dr Whitehouse!
Thanks Leif for your detailed explanation.
I have been noticing that the observed TSI variations being modulated by SC23 (every 27 days) are slowly modulating towards extinction. In fact from your own graph – http://www.leif.org/research/TSI-SORCE-2008-now.png
it can be predicted that we should reach extinction some time later this month.
I’m interested to see what will happen to SC24 when this occurs !
DJ (18:47:47) :
Global temperatures continue to run well above average and the sun remains quite.
– With respect to the current SSN. Your erroneous claims really are a case of the boy who cried “WOLF” !
‘PS Awfully hot in Alaska ATM – ‘
Apr 29 (74 F) and 30 (76 F) both set record highs for the date at Fairbanks. Normal high temps are now in the low 50’s and coming up a degree every two days. April as a whole came in at -0.4 of normal after a brutal first ten days.
But while way above normal for the end of April, those temps are not as hot as it can get up there around the time of the summer solstice with 22+ hours of daylight.
As I have mentioned before, I was stationed in and around Ft Wainwright for eighteen months. I arrived on 10 July, 1969, so I missed by a couple of weeks what must be a record heat wave for Fairbanks in terms of length. Date/High/Low. Normal high temps for the second half of June are in the low 70’s.
That 96 is not the all-time record, by the way, which is, I believe 100F.
06/12/1969 81 51
06/13/1969 82 56
06/14/1969 90 63
06/15/1969 96 62
06/16/1969 85 58
06/17/1969 82 53
06/18/1969 82 50
06/19/1969 84 50
06/20/1969 91 55
06/21/1969 86 57
06/22/1969 88 61
06/23/1969 81 60
06/24/1969 76 54
06/25/1969 78 47
06/26/1969 82 48
06/27/1969 88 55
kim (05:44:06) :
Are the various causes of varying albedo, if albedo be the means through which the mechanism acts, sufficiently distinguishable from each other?
Not from the value of the albedo itself, but we do know if there was a big volcanic eruption…
DJ (18:47:47) :
How about quite sun pushes Fairbanks April temperatures below 63 year average?
http://i599.photobucket.com/albums/tt74/MartinGAtkins/Fairbanks.jpg
Ancient Sun Spot Counting
The official sunspot number for April was 1.2, up from 0.7 for March. The smoothed sunspot number [for October – always 6 month behind] was 1.9. Have to go back to August 1913 to find a lower one [1.8 on my revised scale; 1.5 official]
Out… like a lamb? Some folks will surely disagree:
http://www.greatfallstribune.com/article/20090501/NEWS01/905010328
Ancient Sun Spot Counting – Since glass has been around for about 4000 years, the ancient astronomers probably used a darkened glass to look at the sun, like today. In addition, one of the fun things, as kids, we made a “camera obscura”. Basically a pinhole camera that can project a image on a table or wall, in a darkened room. The ancients were every bit as smart, or smarter then us. They knew what the sun could do to eyes.
Apropos?
History Channel International – Friday May 1, 2009 – 7pm (Central)
Documentary – Little Ice Age: Big Chill
i’m just sayin’…………
Pamela Gray 17:43 (4/30): “The fact that this cluster of spots has occurred in the absence of cycle 24 polarity spots is interesting. So it looks to me like cycle 23 is just being normal. Cycle 24 not so much. But let’s be clear, the Sun is not cooler for lack of spots.”
Geoff Pohanka 18:35:08 (4/30) : “What is most important is that the sunspot was from cycle 23, which will be 13 years long now in May. The last cycle this long was in the 1790s, predating the Dalton Minimum. Cycle 24’s first sunspot was January 2008 and it has had very few spots. So a very long cycle 23, and an almost non existant cycle 24, bodes for a very cool 30 year period coming before us.”
Is this the answer to the comments above?
Ed Zuiderwijk 1:45 (5/1): “This is a common error of thinking, that the momentaneous state of the Sun determines the momentaneous state of the planet. In fact, it’s the accumulated effect over time. Solar activity has been below average for the last 5-6 years, maybe longer. As a result the amount of heat received and stored in the Earth system has been decreased (through direct and, more importantly, indirect effects, such as cloud cover) and the accumulated effect of that over a long period, 10-15 years perhaps will drive the temperature down.
It has been estimated that the excess heat accumulated over the previous 30-40 years due to high Solar activity has now shrunk by 30-40% and is rapidly going down.”
Leif, anyone? Or did I misunderstand your post at 22:37, Leif.
vukcevic (04:14:39) :
This may be, in Dr. Svalgaard’s words, entirely baseless and unfounded speculation, but falling Polar Field strength as measured at Wilcox SO
Yes, such extrapolation is indeed baseless. Why not extrapolate the first two cycles on the left? Or extend the extrapolation another cycle to the right.
pyromancer76 (07:44:08) :
“It has been estimated that the excess heat accumulated over the previous 30-40 years due to high Solar activity has now shrunk by 30-40% and is rapidly going down.”
Leif, anyone? Or did I misunderstand your post at 22:37, Leif.
I don’t know what your question is, but the is no evidence that ‘heat has accumulated over 40 years due to solar activity’ and that it must now come down.
Nice to see a bit of balance on Discovery Channel’s Daily Planet show yesterday. They presented a piece on the quiet Sun and possible correlation to global cooling. Especially given that the shows presenter, Jay Ingram, is an AGW fan and seems to mention it on most shows. He even mentioned “skeptics” of global warming during the Sunspot piece.
Leif Svalgaard (22:37:52)
Thank you Dr. Svalgaard for a most enthralling exposition.Agreed. The number of times people ask “would this spot been seen xxx years ago” gets old after a while. There are some smart people doing this (counting SSN’s).
Leif Svalgaard (00:40:29) :
carlbrannen (00:20:06) :
After that, I’d be interested in what the Fourier transform of the sunspot cycles look like.
It looks like this:
http://www.leif.org/research/FFT-Power-Spectrum-SSN-1700-2008.png
Leif,
So this was done with annual data? Do you have a reason for using annual data rather than monthly data? Just curious.
Where’s the “Gleissberg” cycle in this analysis? I don’t see it, do you?
What’s the critical power factor for 0.05 significance, if you know?
Thanks.
Basil
Kath,
If we send complaints to Daily Planet, we may get balance. I do so. There is a contact link on their web site. He must have looked at the Danish National Space Center web site or Willie Soon’s statements. It really ticks me off that Soon is heard and Sallie Baliunas is not. That’s another issue. They work together! In any case, this is the first acknowledgement by Jay Ingram that there may be two sides to the story.
vukcevic (04:14:39) : your [] should be and with the “i ” inside
I meant “”
“Francis T. Manns (08:55:58) :
If we send complaints to Daily Planet, we may get balance. I do so. There is a contact link on their web site.”
Thanks Francis, I will do so.
Leif 06:46:48
Excellent and thanks. Now, are we observing clouds carefully enough and measuring the input of haze from Asia’s burning and other sources to distinguish these two contributors to albedo?
============================================
“Future generations will be puzzled with our intense divination of [sunspots] for our use in solar predictions ”
Well divined and appropriately struck. Choreography by the augurers themselves from obvious self-interest.
“I think it’s about time we all stand up and put an end to this eco-fascism before it destroys all of our liberties.”
Is the eco-fascism the real worry or only a ceremonial sidearm, like Patton’s pearlhandled revolvers? The wielders of power have simply instigated a world conflict to whip up fervor among the masses, Gaia’s patriots. Useful idiots.
It’s past time.
Carsten: My apologies. I goof up my terms a lot. Local transit time would be better. It would be better to try and observe theses “Faint Fuzzy” umbraless SSN’s near local noontime to put atmospheric extinction at the minimum.
I am at 43N and I have to observe between 1 hour before to 1 hour after solar transit in the sky. Even that doesn’t work any more. If I had adaptive optics hooked up, maybe.
The first thing out of people’s mouths after learing of Deep Solar Minimum is “How does that affect global warming”. Laymen & Politician alike. Warming is intuitively associated with the Sun.
Solar inactivity is associated with cooling.
You don’t even have to say it.
Therefore, Deep Solar Minimum puts AGW on the defensive….at the basic Human instinct level.
Basil (08:53:53) :
So this was done with annual data? Do you have a reason for using annual data rather than monthly data?
Just that the record is longer.
Here is the monthly FFT [raw and smoothed – exercise for student: which is which?]:
http://www.leif.org/research/FFT-SSN-Monthly-1755-2007.png
Doesn’t make any difference.
Where’s the “Gleissberg” cycle in this analysis? I don’t see it, do you?
There is a lot of power out in the 50-120 year range. That is the Gleissberg cycle. But it is not a real ‘cycle’ just a ‘tendency’ [spots were low 1700s, 1800s, 1900s, and 2000s].
What’s the critical power factor for 0.05 significance, if you know?
I tend not to pay attention to this as the series does not conform to the assumptions behind that measure. A better criterium is to do the FFT on the first half and the second half of the data and see what difference it makes:
http://www.leif.org/research/FFT-SSN-two-halves.png
Judge for yourself.
Adolfo Giurfa (09:19:56) :
I meant “”
this is hard to get right. To make an < sign use ampersand, the two letters lt, and a semicolon. For > use gt as the two letters.
kim (09:36:03) :
Now, are we observing clouds
People are trying. We shall see. Eventually they will get it right.
Leif Svalgaard (08:12:45) :
vukcevic (04:14:39) :
[“This may be, in Dr. Svalgaard’s words, entirely baseless and unfounded speculation, but falling Polar Field strength as measured at Wilcox SO.
Yes, such extrapolation is indeed baseless. Why not extrapolate the first two cycles on the left? Or extend the extrapolation another cycle to the right.”]
No problem sir.
http://www.geocities.com/vukcevicu/LP-project1.gif
Extrapolation to the left:
As you know Wilcox SO data starts in 1976, so prior data are from Mnt. Wilson Observatory which is available since 1967.
One should necessarily assume that reduction in the intensity is absolutely linear and that it should have started from an excessively high level. Amplitude envelope is most likely another longer term cycle, which may take us back to SC13 and further back (cyclically) to Dalton and Maunder, and forward to New Dalton in the late 2020s.
Extrapolation to the right:
No data beyond 2009, so if you forgive me taking the liberty to follow course of my (Vukcevic) formula.
I suspect aforementioned cyclical envelope will take off in the late 2020s, and solar activity will accordingly intensify.
But of course, this is not science, it is just peace of NAÏVE ART !
It is all in the eyes of the beholder!
pyromancer, if cycle 24 were acting like a normal active cycle, and a cycle 23 spot showed up just like it did this week, that would be normal. There would be no sudden discussion of this weird occurrence. Old spots do that. Overlap is normal. This spot is normal. We make the mistake of saying something is abnormal about cycle 23 just because cycle 23 spots show up every now and then. What is interesting is the lack of a ramp for Cycle 24. The rather arbitrary Minimum measurement happens more because of the ramp of the next cycle, not the old one. Cycle 23 is acting quite normal.
Basil (08:53:53) :
“Leif,
Where’s the “Gleissberg” cycle in this analysis? I don’t see it, do you? ”
The FFT Spectrum analysis chart is an important reference. Thanks Dr. Svalgaard.
I do not see “Gleissberg” cycle either.
But I do see the second most powerful cycle (after 11 year one) with period of approx 107 years, with its half period of 53.5 years. This concurs in an excellent manner with another product of NAÏVE ART of mine.
http://www.geocities.com/vukcevicu/SSNanomaly1.gif
This clearly identifys all known mayor anomalies of recorded SSNs.
Trigonometric transformation dictates fundamental period of 107 = (118+96)/2
Leif 22:37:52
What does the earth’s weakening magnetic field together with the reduced solar wind portend bedsides the increased GCRs? Have you been analyzing the newly discovered breaches in the earth’s magnetosphere by the THEMIS spacecraft?
The FFT Spectrum analysis chart
http://www.leif.org/research/FFT-Power-Spectrum-SSN-1700-2008.png
vukcevic (10:13:52) :
But of course, this is not science, it is just peace of NAÏVE ART
Perhaps there is [another] blog for that
It is all in the eyes of the beholder!
A famous American ball player, Yogi Berra (known for his marvelous sayings) has this to say about that:
“If I hadn’t believed it, I wouldn’t have seen it”.
vukcevic (10:33:59) :
“I do not see “Gleissberg” cycle either.”
The ~108 year period is the Gleissberg ‘cycle’
Pamela Gray (10:15:25) :
Cycle 23 is acting quite normal.
Absolutely, and so is cycle 24 [for a small cycle].
vukcevic (10:13:52) : and further back (cyclically) to Dalton and Maunder
We are waiting for it 🙂
Dj asks
“Global temperatures continue to run well above average and the sun remains quite. How much longer before we are willing to admit that this is entirely consistent with the enhanced greenhouse effect?”
Well firs off what the heck is “average” mean in this context? Are you only counting periods of widespread famine? Or how about have you ever heard of thermal inertia? did you really think the change would be instant? Perhaps you think temperature should have declined 800 years ago in response to this months quiet sun? Kinda like the claim that CO2 drives temperature in the historic record?
That’s my answer then, using the AGW standard the cooling of the little ice age was caused byn the weak sunspot cycle 24. Perfect and that answer has all the scientific rigor of the AGW theory.
vukcevic (10:13:52) :
Why not extrapolate the first two cycles on the left?
I meant take the two cycles to the left and extrapolate those to the right.
No problem sir.
http://www.geocities.com/vukcevicu/LP-project1.gif
Extrapolation to the left:
As you know Wilcox SO data starts in 1976, so prior data are from Mnt. Wilson Observatory which is available since 1967.
The MWO data for the first cycle are not any higher that the WSO data for the second cycle, so the extrapolated line should not go up on the right, if the goal is for it to match the data.
As I said, there is no base for your linear extrapolation.
vukcevic (10:13:52) :
“Why not extrapolate the first two cycles on the left?”
I meant take the two cycles to the left and extrapolate those to the right.
No problem sir.
http://www.geocities.com/vukcevicu/LP-project1.gif
Extrapolation to the left:
As you know Wilcox SO data starts in 1976, so prior data are from Mnt. Wilson Observatory which is available since 1967.
The MWO data for the first cycle are not any higher that the WSO data for the second cycle, so the extrapolated line should not go up on the right, if the goal is for it to match the data.
As I said, there is no base for your linear extrapolation.
Robert Bateman (09:45:19) :
Carsten: My apologies. I goof up my terms a lot. Local transit time would be better. It would be better to try and observe theses “Faint Fuzzy” umbraless SSN’s near local noontime to put atmospheric extinction at the minimum.
No worries. Yes that makes sense, at your latitude it the difference between transit is and zenith passage is small. Local noontime should indeed be local, disregarding summertime, adjusted for longitude etc. Local transit time works for all latitudes and longitudes.
I am at 43N and I have to observe between 1 hour before to 1 hour after solar transit in the sky. Even that doesn’t work any more. If I had adaptive optics hooked up, maybe.
One year ago I captured an SC24 spot
http://arnholm.org/astro/sun/sc24/sc24_spot_20080504_1010ut.jpg
http://arnholm.org/astro/sun/sc24/sun_20080503.jpg
Now the sun is high enough to try again, but I wonder if I will ever get the chance to see another one big enough….
Pamela Gray and Leif Svalgaard, thanks and I understand from you that Cycle 23 is “acting normally” and we are waiting and waiting on #24. My question is has the small variance in TSI declined in some small significant way such that there has been less heat/energy/irradiance for earth climate systems to use. As I look at Leif’s TSI Reconstruction Chart, it seems that total TSI might have declined since 1992.5. I feel certain this issue has been studied many times, but are there articles examining the tiny changes in TSI over time and the time lag of any consequences? I realize that this is only variable among many, but it seems like an essential one in any gathering of influences on climate. We focus so much on sunspots —
DJ (18:47:47) :
PS Awfully hot in Alaska ATM – http://www.wunderground.com/US/AK/Fairbanks.html . Perhaps worth a report?
Does it matter that Fairbanks ended the month of April below normal as a whole? Or would that be the ‘conveniently left out of the article’ in the alarmist “Fairbanks breaks April record; global warming cited” news stories that are circulating
DJ, check out the jet stream as to why Fairbanks is warm and Russia is cold just across the strait.
Yes it has and no it doesn’t. Just do a search on solar output and global temperature. You will find lots of articles. Doesn’t mean they are any good. Read with a discerning eye. Slop does and always will get published. Climate models actually have a tiny little calculation (using the wrong TSI) for solar input. But even if they used the right one, it wouldn’t make a difference. The noise is too great.
Leif Svalgaard (10:41:01) :
vukcevic (10:13:52) :
…….. it is just peace of NAÏVE ART
Perhaps there is [another] blog for that
Ok, I will call it ‘Solar Naïve Art’ ; even NASA has space for some arty stuff.
I thought it would brake monotony while some of us are waiting for a paltry inadequate sunspot to make its appearance.
Leif Svalgaard (10:41:01) :
The ~108 year period is the Gleissberg ‘cycle’
Mine is 107 years, so to be true to my immodest self I will call it ‘Vukcevic Cycle’
It precisely defines alternative occurrences of long min followed by reduced cycle in regular sequence, that is what I call a cycle.
http://www.geocities.com/vukcevicu/SSNanomaly1.gif
But, I am confused, not long ago you were saying G’s cycle is 82 or 89 years, now 108. As you know, cycle is something that repeats itself regularly, so it can’t be 82 and 108 years at the same time.
By the way, what is your definition of the Gleissberg ‘cycle’, I hope it is as nice and neat, as my definition of 107 year cycle and represented by my formula (is there one for the Gleissberg cycle ? ). Perhaps you could tell us when did last Gleissberg cycle started and finished.
Leif Svalgaard (11:07:52)
I meant take the two cycles to the left and extrapolate those to the right.
Sorry, failed to understand ! My brain is wired for an obscure dialect of a miner South European language.
Leif Svalgaard (11:07:52)
The MWO data for the first cycle are not any higher that the WSO data for the second cycle, so the extrapolated line should not go up on the right, if the goal is for it to match the data.
I am lost again, did you mean to the left? However, here is part of my post you may have missed in your hasty call ‘burn the heretic’.
vukcevic (04:14:39) :
One shouldn’t necessarily assume that reduction in the intensity is absolutely linear and that it should have started from an excessively high level. Amplitude envelope is most likely another longer term cycle, which may take us back to SC13 and further back (cyclically) to Dalton and Maunder, and forward to New Dalton in the late 2020s.
http://www.geocities.com/vukcevicu/LP-project1.gif
Leif Svalgaard (11:07:52)
As I said, there is no base for your linear extrapolation.
But it does look pretty good, don’t you agree ?
May I conclude this exchange with my expression of thanks and gratitude, your challenges are great inspiration to me, if you persevere, I may even take up proper science.
That Independent article is a real cracker, suggestive of public perception paradigm shift in the offing IMO
Maybe I missed it but if compass needle deflection and solar flux are proxies for sunspot activity and those records go back 250 years (well at least the compass needle deflection), then how much of the sunspot activity were they missing by direct observation back then as compared to today (excluding the flies in the ointment)?
Thanks Leif
I had forgotten Wolf etc. I should have remembered.
Ancient Sun Counting Revisited – Looks like my last post was contracted. Anyway, the ancients probably used colored glass, since it was avialable about 4000 years ago. They also could have used a device we made as kids, called the “camera obscura” . It’s like a pinhole camera, that projects a image on a surface in a darkened room. By a simple mirror one can project the image on a table. They were well aware of what would happen by gazing at the sun to long.
vukcevic (12:25:59) :
But, I am confused, not long ago you were saying G’s cycle is 82 or 89 years, now 108. As you know, cycle is something that repeats itself regularly, so it can’t be 82 and 108 years at the same time.
Even you has used the phrase ‘solar cycle’, in spite of the period being anywhere from 7 to 17 years.
One shouldn’t necessarily assume that reduction in the intensity is absolutely linear and that it should have started from an excessively high level.
In that case the line should not have been drawn to be linear.
But it does look pretty good, don’t you agree ?
No, it looks lousy as per the above comments.
if you persevere, I may even take up proper science.
God forbid 🙂
Leif Svalgaard (22:37:52) :
Dr Svalgaard
Thank you for the erudite explanation.
Here is the link to Leif’s comment for reference:
http://wattsupwiththat.com/2009/04/30/see-speck-run/#comment-124646
John G (12:55:41) :
how much of the sunspot activity were they missing by direct observation back then as compared to today (excluding the flies in the ointment)?
about 40% before 1890s and 20% up to 1945. see http://www.leif.org/research/Napa%20Solar%20Cycle 24.pdf
Leif Svalgaard (15:26:46) : Your comment is awaiting moderation
John G (12:55:41) :
how much of the sunspot activity were they missing by direct observation back then as compared to today (excluding the flies in the ointment)?
about 40% before 1890s and 20% up to 1945. see http://www.leif.org/research/Napa%20Solar%20Cycle%24.pdf
better link
Hello Leif
Neither link worked for me. I’d like to see.
vukcevic (12:25:59) :
One shouldn’t necessarily assume that reduction in the intensity is absolutely linear and that it should have started from an excessively high level.
Leif Svalgaard (15:23:07)
In that case the line should not have been drawn to be linear.
Remember something called Taylor/Maclaurin series:
Sin x = x – (x exp 3)/3! +….. etc
The rest is inconsequential chat, one just might have over glass of Napa white.
Just The Facts (20:17:13) :
Hello Leif
Neither link worked for me. I’d like to see.
I think this is the URL Leif tried to post twice, but unsuccessfully.
http://www.leif.org/research/Napa%20Solar%20Cycle%2024.pdf
This one works here.
vukcevic (12:25:59) :
One shouldn’t necessarily assume that reduction in the intensity is absolutely linear and that it should have started from an excessively high level.
Leif Svalgaard (15:23:07)
In that case the line should not have been drawn to be linear.
I suspect by invoking the Taylor/Maclaurin for small value of x
Sin x = x – (x exp 3)/3! +….. etc
Dr. Svalgaard (true and consistent scientist as he is, the guardian of the classical solar science thought) may not be entirely satisfied.
Taking up his challenge, by modifying my already quoted SSN Anomaly formula
http://www.geocities.com/vukcevicu/SSNanomaly1.gif
I have produced (another example of naïve solar art) an approximation to show that the Solar Magnetic Field have a (non linear) cyclical oscillations. The graph covers period of 300 years 1750 – 2050.
http://www.geocities.com/vukcevicu/SMF-strength.gif
Y = A (1.5+COS(3pi/2+2pi(t-1941)/118)+0.5COS(2pi(t-1941)/(3*96)))
This is only an initial attempt, but it clearly shows near linear change from 1980 – 2020 as suggested previously:
http://www.geocities.com/vukcevicu/LP-project1.gif
If you follow my posts, I will combine two in the next few days.
Note: Solar magnetic field will never ‘drop and stay at zero’ (result may be longer period random surface field with multi polarity distribution).
If this chart is an approximate reflection of reality ( nonsense! says Dr. S. ) than it is to be expected that ‘new Dalton’ wouldn’t be as low as Dalton proper, but deeper than SC14.
Thanks for the link Leif. 40% early on and 20% later are pretty big discrepancies. Do they use your recalibrated sunspot numbers now?
vukcevic (04:26:33) :
I have produced (another example of naïve solar art) an approximation to show that the Solar Magnetic Field have a (non linear) cyclical
I don’t think you get the point. Any short enough piece of a curve can be approximated by a straight line, it is just that there is no physical basis for assuming that the Sun follows that line (especially since the fit isn’t that good to begin with).
John G (07:08:18) :
Thanks for the link Leif. 40% early on and 20% later are pretty big discrepancies. Do they use your recalibrated sunspot numbers now?
No, and that may take twenty years or more. A case in point is the Group Sunspot Number by Hoyt and Schatten. It differs a lot from the Wolf number and people cherry pick which one of the series to use depending on what they want to show. A definition of ‘good’ data has always been the set that supports one’s pet ideas the best.
Leif Svalgaard (07:41:02) :
I don’t think you get the point…. it is just that there is no physical basis for assuming that the Sun follows that line…
http://www.geocities.com/vukcevicu/SMF-strength.gif
You are convinced that there is no physical basis to it. I got that point some time ago.
On the other hand, as you often say, “sun is a messy place”, so just it might be.
The problem here is:
I’ve shown that there might be something to it, too many coincidences in the formulae to be ignored. I accept: “there is no physical basis as far as the current science knows”, but that leaves tiny possibility that I am right, and that wouldn’t do.
On the plus side, according to this ‘astrology’ your estimate of SC24 is close to the mark but SC25 may be a bit too optimistic. I feel privileged that our predictions more or less agree, even if methods do not, but I am sorry that as a result, our exchanges could not be a bit more productive.
Thanks for keeping my brain awake.
vukcevic (09:36:39) :
You are convinced that there is no physical basis to it.
No, this is totally wrong. I’m not convinced there is no basis. You have to show that there is and convince me there is.
On the other hand, as you often say, “sun is a messy place”, so just it might be.
‘might be’ is not correct. If a prediction is right for the wrong reason, it is actually wrong.
I’ve shown that there might be something to it, too many coincidences in the formulae to be ignored.
As I have pointed out many times, the number of degrees of freedom is so low that coincidences could easily be ignored by people with even a minimum of statistical training or knowledge.
our estimate of SC24 is close to the mark but SC25 may be a bit too optimistic.
SC25 cannot be predicted yest [it can be guessed at].
Thanks for keeping my brain awake.
Then put it to use…
Leif Svalgaard (09:57:31) :
No, this is totally wrong. I’m not convinced there is no basis. You have to show that there is and convince me there is.
I have to convince myself first.
M.V. Thanks for keeping my brain awake.
L.S. Then put it to use…
That is easier said than done.
vukcevic (10:38:23) :
L.S. “Then put it to use…”
That is easier said than done.
It shows 🙂
Leif Svalgaard (07:32:49) :
Geoff Sharp (04:21:01) :
I would like hear Leif’s account of how much CO2 is affecting world temps. His past statements to the press would suggest quite a bit?
I would estimate a few tenths of a degree at the most.
Recent CO2 data suggests an increase of
388ppm-280ppm = 108ppm increase
108/280 doubling = ~39%
Estimated effect of doubling CO2 on global temps ~1.0-1.2 degrees (without feedback) 39% X 1.1 (ave.) = .43 degrees.
Considering your recent revelation (to me at least) of expertise in atsmospheric physics, I would like your opinion on the above disparity between IPCC estimated effect and yours. Or is .43 essentially equivalent to a few tenths.
Respectively submitted,
Tim
That should read “Respectfully”, Leif always intimidates my typing.
Tim Clark (10:46:22) :
Considering your recent revelation (to me at least) of expertise in atmospheric physics, I would like your opinion on the above disparity between IPCC estimated effect and yours. Or is .43 essentially equivalent to a few tenths.
Mine is just a rough calculation [guess even], while they claim theirs is ‘settled science’. What I meant was that I’m comfortable with a claim [by others] of a few tenths, but not with ten times as much.
Although Central England is not Global, it does sport one of the longest temperature reconstructions. One can compare that with the logarithm of the CO2 concentration: http://leif.org/research/CET2.png and note that increases like the one recently have been seen in the past. I have singled those out and plotted the temperature and CO2 for each: http://leif.org/research/CETandCO2.pdf
I don’t see more than a ‘few tenths’ if even that.
BTW, the above plot was what me banned at tamino’s http://tamino.wordpress.com/
Thanks, Leif.
Spotless days page has just been updated
SC24 has crossed the 600 spotless days limit and still climbing fast as ever
http://users.telenet.be/j.janssens/Spotless/Spotless.html#Evolution
Smoothed spotless days is getting very high indeed
http://users.telenet.be/j.janssens/Spotless/Spotless.html#Wolf
Main characteristics per solar cycle
http://users.telenet.be/j.janssens/Spotless/Spotless.html#Main
“… if SC24 belongs in the category of the old cycles, then minimum would take place mid-2009 (March 2009 at the earliest). But then SC23 would have last over 13 years, making it one of the longest solar cycles over the last 250 years (SC04: 169 months). Though unlikely, if SC24 is not going into a higher drive soon, then SC23 is certainly ready to make an assault on this over 200-year old record.”
We live in interesting times.
Leif Svalgaard (11:08:54) :
Although Central England is not Global, it does sport one of the longest temperature reconstructions. One can compare that with the logarithm of the CO2 concentration: http://leif.org/research/CET2.png and note that increases like the one recently have been seen in the past. I have singled those out and plotted the temperature and CO2 for each: http://leif.org/research/CETandCO2.pdf
Leif Not sure you saw these I posted before
they are temperature vs co2 and temperature vs tsi/ssn
There is some correlation between temp and co2 (but does temp cause co2 increase or vice versa). using a linear curve fit (not shown) gives approx 0.01deg C per ppm!
There is little correlation between tsi and temperature
bill (15:38:02) :
they are temperature vs co2 and temperature vs tsi/ssn
No, just temperature and CO2. Scroll down on http://leif.org/research/CETandCO2.pdf to see the last plots of ‘global’ temperatures.
Carsten Arnholm, Norway (11:32:09) :
then SC23 is certainly ready to make an assault on this over 200-year old record.”
SC21 lived on 3 years after the official minimum, and SC22 lived on 2 years after the official minimum, so no wonder that SC23 is still with us [as it will be for another2-3 years]. See page of of http://www.leif.org/research/Most%20Recent%20IMF,%20SW,%20and%20Solar%20Data.pdf
We live in interesting times.
Nevertheless true.
Leif Svalgaard (20:25:27) :
bill (15:38:02) :
“they are temperature vs co2 and temperature vs tsi/ssn”
No, just temperature and CO2. Scroll down on
Sorry, scratch that. I misread your comment [self-centeredly] thinking it referred to my plot.
Leif Svalgaard (20:28:57) :
See page 4 of http://www.leif.org/research/Most%20Recent%20IMF,%20SW,%20and%20Solar%20Data.pdf
Leif Svalgaard (22:37:52) :
If I understand you the effect of the UV induced ionization on the earth’s magnetic field is the product of the charge density and the thermal wind induced charge velocity. Do we have an independent estimate of thermal wind velocity? Is it constant? or does it vary enough to affect the currents generated?
By the way, that was one of the best posts I’ve ever seen.
Bob Meyer (21:35:22) :
Is it constant? or does it vary enough to affect the currents generated?
The variation is quite regular and has a strong [but predictable] dependence on the Sun’s zenith angle [i.e. seasonal variation]. You can f.ex. go to this website: http://www.gfz-potsdam.de/portal/-?$part=CmsPart&docId=2215117 and ask for 30 days of data. The top plot shows the diurnal variation of the Declination. Select ‘plot’. The ‘noise’ generally cancels out over a month, but one can in any case remove two or three days of strongest activity [which usually happens at night and is unrelated to the UV]
By the way, that was one of the best posts I’ve ever seen.
Thanks for the kind words. One tries…
Bob Meyer (21:35:22) :
Is it constant? or does it vary enough to affect the currents generated?
I forgot to mention that we don’t need to know the density or velocity of the charges. We simply measure their magnetic effect on the ground. But we do know from rocket and/or radar measurements how things vary and depend on each other. Our knowledge here is extensive and this phenomenon is well understood [at least for the use we make of it for the sunspot calibration].
Leif Svalgaard (22:35:42)
Thanks for the informative reply.
Leif Svalgaard (20:28:57) :
SC21 lived on 3 years after the official minimum, and SC22 lived on 2 years after the official minimum, so no wonder that SC23 is still with us [as it will be for another2-3 years]. See page of of http://www.leif.org/research/Most%20Recent%20IMF,%20SW,%20and%20Solar%20Data.pdf
I think you mean to say page 4. The difference is if course that both SC23 and SC24 activity is now very, very low. If we assume that SC23 keeps on going for another 2-3 years as you suggest. and as it has tried the last couple of months, while at the same time SC24 remains in the waiting room, we might end up with a very long SC23.
Carsten Arnholm, Norway (02:43:31) :
The difference is if course that both SC23 and SC24 activity is now very, very low. If we assume that SC23 keeps on going for another 2-3 years as you suggest. and as it has tried the last couple of months, while at the same time SC24 remains in the waiting room, we might end up with a very long SC23.
Yes, but my point is that the length of cycle 23 is really determined by a property of cycle 24, rather than of 23.
Dr. Svalgaard
Is Dr. Hathaway challenging accuracy of polar field prediction method;
Polar Field Strength gives 75 ± 30.
(Svalgaard, Cliver, & Kamide, 2005 give an error of ±8 but this represents the error in the measurement of the polar field, not the error in the accuracy of the prediction)
Dr. David H. Hathaway http://solarscience.msfc.nasa.gov/presentations/20090207Astrofest_SunspotCycle.ppt
I hope not, since my polar fields tracking formula depends on your method to project forward to SC24 and beyond.
I just noticed this sunspot adjustment from NOAA
Note: The Solar Influences Data Center in Belgium reports two small, previously unnumbered sunspots on April 6th and April 22nd. Accordingly, we have reduced the number of spotless days for 2009 by 2.
What is going on here ?
What is the minimum criteria for defining whether or not a SSN should be assigned ?
This kind of behaviour from NOAA seems to be more common in recent times. To my thinking, this is a distortion of the SSN in terms of the historical reporting method.
The current doppler images show how long SC23 will go…sunspots are tied to the differential flows and SC23 shows scope for more sunspots to come.
http://users.beagle.com.au/geoffsharp/comb2.gif
Anthony, I also second the motion to keep Leif’s explanation in the : Leif Svalgaard (22:37:52) : post someplace permanently where one could refer repetitious questions.
Maybe another tab , like the “projects” tab. A FAQ on sun and various facts as far as this blog knows them.
vukcevic (05:12:28) :
Is Dr. Hathaway challenging accuracy of polar field prediction method;
David is of his rocker with this. The measurement error of the polar fields is very small (of the order of 1 microTesla). Estimating the error bar on a prediction is as hard as [or harder than] the prediction itself. In our paper we estimated the error from the differences between predicted and observed values and found it to be very small (or the order of 2, so 75+/-2). We arbitrarily increased that to 8 because at the time, we only had the first year of the polar year data, rather than the three we would have liked. David’s +/-30 is out of the blue, but may be chosen because that would allow him [in due time] to claim that he agreed with our prediction.
Ozzie John (05:19:27) :
I just noticed this sunspot adjustment from NOAA
Where did you see that. NOAA does not keep track of spotless days…
Ozzie John (05:19:27) :
I just noticed this sunspot adjustment from NOAA […]
What is going on here ?
Never mind I saw it on:
http://www.spaceweather.com/
That site is not an official NOAA site, so nothing is going on, just the site maintainer adjusting his own interpretation of the data.
Geoff Sharp (05:28:58) :
The current doppler images show how long SC23 will go…sunspots are tied to the differential flows and SC23 shows scope for more sunspots to come.
The current Doppler images etc have nothing to do with this [and if anything, the torsional oscillation is a consequence of the activity, not the cause of it]. Every solar cycle drags on for some time after the official minimum.
What are the huge dark areas in the center of the sun in
http://sohowww.nascom.nasa.gov/data/realtime/realtime-update.html
In EIT1771 EIT195 and EIT284
??
Nothing showing in the MDI
EIT (Extreme ultraviolet Imaging Telescope) images the solar atmosphere at several wavelengths, and therefore, shows solar material at different temperatures. In the images taken at 304 Angstrom the bright material is at 60,000 to 80,000 degrees Kelvin. In those taken at 171 Angstrom, at 1 million degrees. 195 Angstrom images correspond to about 1.5 million Kelvin, 284 Angstrom to 2 million degrees. The hotter the temperature, the higher you look in the solar atmosphere.
anna v (09:43:00) :
What are the huge dark areas in the center of the sun
It is a ‘coronal hole’. An area of the Sun where the magnetic field is largely weak and of one polarity, thus ‘open’ to the solar wind, that simply lifts the corona away from the Sun in such areas. You see similar ones around the poles. The solar wind speed is high in coronal holes, we would expect such high speed wind to impact the Earth in about 4 days producing geomagnetic storms and aurorae. This is a very good prediction.
Leif Svalgaard (09:50:18) :
The solar wind speed is high in coronal holes, we would expect such high speed wind to impact the Earth in about 4 days producing geomagnetic storms and aurorae. This is a very good prediction.
I just looked at the image. The coronal hole is not quite at disk center yet, so add another day to the prediction.
Leif Svalgaard (11:08:54)
Hmmm…. Leif Svalgaard is banned by Tamino but TCO still enters almost 1/5 of all the comments. Interesting world we live in.
Leif Svalgaard (07:57:16) :
Geoff Sharp (05:28:58) :
The current doppler images show how long SC23 will go…sunspots are tied to the differential flows and SC23 shows scope for more sunspots to come.
—————————————————
The current Doppler images etc have nothing to do with this [and if anything, the torsional oscillation is a consequence of the activity, not the cause of it]. Every solar cycle drags on for some time after the official minimum.
Interesting comment….The slower regions are produced at the Tachocline and rise to the surface, separating and stretching in the process due to the Sun’s angular momentum from rotation. Could you explain how the sunspot cycle has a hand in this process of forming the torsional oscillation bands.
rephelan (16:37:15) :
Hmmm…. Leif Svalgaard is banned by Tamino but TCO still enters almost 1/5 of all the comments. Interesting world we live in.
Perhaps because my insightful and penetrating analyses were seen by tamino to be a much greater threat than TCO’s 🙂
Geoff Sharp (17:54:57) :
Could you explain how the sunspot cycle has a hand in this process of forming the torsional oscillation bands.
It seems that with you I have to explain everything several times over:-)
One of the better models is by Spruit:
Origin of the torsional oscillation pattern of solar rotation
H.C. Spruit (Submitted on 9 Sep 2002 (v1), last revised 19 Oct 2002 (this version, v2))
A model is presented that explains the `torsional oscillation’ pattern of deviations in the solar rotation rate as a geostrophic flow. The flow is driven by temperature variations near the surface due to the enhanced emission of radiation by the small scale magnetic field. The model explains the sign of the flow, its amplitude and the fact that the maxima occur near the boundaries of the main activity belts. The amplitude of the flow decreases with depth from its maximum at the surface but penetrates over much of the depth of the convection zone, in agreement with the data from helioseismology. It predicts that the flow is axisymmetric only on average, and in reality consists of a superposition of circulations around areas of enhanced magnetic activity. It must be accompanied by a meridional flow component, which declines more rapidly with depth.
Paper here: http://arxiv.org/abs/astro-ph/0209146
Leif Svalgaard (18:32:40) :
It seems that with you I have to explain everything several times over:-)
I dont recall discussing this precise question before, perhaps you could enlighten me or maybe its an attempt at humor?
Spruit’s model is another interesting observation, but it is just that and cannot be stated as fact. To suggest surface variations are driving this oscillation to the tachocline seems at odds with Dr. Howes work.
Another observation is the oscillations are created at the tachocline in the shear layer between the convective and radiative zones from torque applied from acceleration and deceleration (explaining polarity changes). This extends and breaks up on its way to the top of the convective zone until we get the observed patterns and lays the ground work for future sunspots. This theory could be disproved if the Sun or the core was shown to be completely static. On the small amount of data I have been able to find, it does suggest the Sun’s rotation rate does vary?
http://users.beagle.com.au/geoffsharp/howefig25.png
http://users.beagle.com.au/geoffsharp/comb2.gif
thanks to a moderator for correcting my typos.
Reply: de nada. ~dbs
Geoff Sharp (19:44:15) :
I dont recall discussing this precise question before, perhaps you could enlighten me or maybe its an attempt at humor?
I have pointed out many times that the TO is the result of activity, not the cause of it. It is not funny to have to state this important fact again and again. If you want to be taken seriously, perhaps you should stop the comedy act.
To suggest surface variations are driving this oscillation to the tachocline seems at odds with Dr. Howes work.
Spruit and other’s explanations are theoretical understanding, not observations. The actual data is not good enough to discriminate which way it goes.
Another observation is the oscillations are created at the tachocline in the shear layer between the convective and radiative zones from torque applied from acceleration and deceleration (explaining polarity changes).
This is not observation, but speculation. Perhaps explain how the polarity changes…
We have ourselves studied this problem, e.g. http://www.leif.org/research/ast10867.pdf
Both the observations and the theory are still incomplete, but there is general convergence of thought as to the importance of the magnetic field and/or temperature variations acting back on the flow. Section 8.5 of http://solarphysics.livingreviews.org/Articles/lrsp-2005-1/ has more on this.
There is little, if any, evidence that the TO is driving the solar cycle.
Leif Svalgaard (20:53:38) :
Like I said i dont recall such discussions, maybe you had them with someone else.
All we have is observations, theory and speculation and Spruit’s paper is extremely speculative and is full of weasel words. To put this paper forward as some sort of evidence that TO is a product of the sunspot cycle is not convincing.
I would think a better method would be to accept the gaping hole of knowledge in this area and not discount other theories unless obviously flawed.
In my speculation I suggest the the polarity change comes about by the magnetic fields created at the tachocline, change occurring on the deceleration/acceleration change over. But it all comes down to rotation rates of the Sun which seems hard to come by (or could be an internal rotation of the core). This is an area of science not well catered for, which surprises me as it would answer many questions.
What is happening with the solar rotation rate???
Geoff Sharp (22:12:47) :
Like I said i dont recall such discussions…
March 9th, 2009 Solarcycle24.com
Spruit’s paper is extremely speculative and is full of weasel words..
I just re-read Spruit’s paper. Spruit is one of the World’s foremost investigators of solar motions and convection. His work carries great weight. To get a feeling for his work: http://adsabs.harvard.edu/cgi-bin/nph-basic_connect?qsearch=spruit&version=1
The paper is not speculative. On the contrary it is quantitative and makes detailed predictions, most are which match the meager data we have. ‘Weasel words’ are normal in this kind of work, and are not meant as a way of ‘weaseling out’. The paper makes very detailed and testable predictions.
In my speculation I suggest the polarity change comes about by the magnetic fields created at the tachocline, change occurring on the deceleration/acceleration change over.
This is no explanation at all. How does the change over ‘change the polarity’, and the ‘polarity’ of what?
But it all comes down to rotation rates of the Sun which seems hard to come by…[…]
What is happening with the solar rotation rate???
And again, the TO has little to do with the rotation or its rate. The TO is a zonal flow, a narrow ‘wind’ or ‘jet’, like the jet stream in the Earth’s atmosphere.
The clearest clue is that the energy in the flow is much, much smaller than the energy in the magnetic field it is supposed to create or control. The tail wagging the dog it would be.
Leif Svalgaard (23:00:13) :
March the 9th you made 4 statements….but there was no discussion.
1: the Doppler images do not show solar rotation, but ‘zonal flows’ i.e. winds in the atmosphere.
2: the low-latitude sunspots of cycle 23 help generate the faster flow
3: the wind is a consequence of solar activity, not the cause of it.
4: explain to us how the angular momentum disturbance would cause the wind in such a narrow belt, or the wind at all.
Point 3 being the total of the discussion.
Spruit’s paper in his intro uses the word “could” 7 times. You might hold him in high regard but his paper is nothing but unproved theory. I would prefer to hedge my bets on this one.
The clearest clue is that the energy in the flow is much, much smaller than the energy in the magnetic field it is supposed to create or control. The tail wagging the dog it would be.
It is also very likely that a lot of the flow strength has dissipated by the time it reaches the surface (2 years later) but retains it magnetic properties. But lets see if we can get an answer to my previous question.
What is happening with the solar rotation rate???
Leif Svalgaard (23:00:13) :
March the 9th you made 4 statements….but there was no discussion.
1: the Doppler images do not show solar rotation, but ‘zonal flows’ i.e. winds in the atmosphere.
2: the low-latitude sunspots of cycle 23 help generate the faster flow
3: the wind is a consequence of solar activity, not the cause of it.
4: explain to us how the angular momentum disturbance would cause the wind in such a narrow belt, or the wind at all.
Point 3 being the total of the discussion.
Spruit’s paper in his intro uses the word “could” 7 times. You might hold him in high regard but his paper is nothing but unproved theory. I would prefer to hedge my bets on this one.
The clearest clue is that the energy in the flow is much, much smaller than the energy in the magnetic field it is supposed to create or control. The tail wagging the dog it would be.
It is also very likely that a lot of the flow strength has dissipated by the time it reaches the surface (2 years later) but retains it magnetic properties. But lets see if we can get an answer to my previous question.
What is happening with the solar rotation rate???
Am late as usual but I had to mention this. Seems that the Belgium spot counters are worried about the lack of spots so they added the two un-numbered specks on the 6th and 22nd to their count!!! That puts 25 spotless days in April, 105 this year and 616 this lull.
Geoff Sharp (23:52:51) :
What is happening with the solar rotation rate???
Is anything happening?
Leif Svalgaard (06:06:39) :
Geoff Sharp (23:52:51) :
What is happening with the solar rotation rate???
———————————–
Is anything happening?
Apart from you ducking the question I am not too sure. There does not look to be too much information in this area….was hoping with your incredible knowledge you could inform?
Geoff Sharp (06:48:15) :
Apart from you ducking the question I am not too sure. There does not look to be too much information in this area….was hoping with your incredible knowledge you could inform?
I never duck a question. Nothing is happening. Can’t inform on nothing.
Geoff Sharp (06:48:15) :
Apart from you ducking the question I am not too sure.
Reanalysis of MDI data shows a significantly slower TO during solar cycle 23, but since the TO [zonal flows or winds] has nothing to do with the the rotation rate, it is fair to say that nothing is happening with the rotation rate.
Leif Svalgaard (07:28:47) :
Geoff Sharp (06:48:15) :
Apart from you ducking the question I am not too sure.
———————————————-
Reanalysis of MDI data shows a significantly slower TO during solar cycle 23, but since the TO [zonal flows or winds] has nothing to do with the the rotation rate, it is fair to say that nothing is happening with the rotation rate.
That is your (and others) speculation. Zonal flows might have nothing to do with rotation rate. But the interesting point is that we have a “confirmed” change of rotation of the Sun. If this is the case like the earth/moon system there must be a trade off in relation to conserving angular momentum….this should be able to be determined.
Do you have a link for the SC23 rotation reanalysis?
Today is May 4
I looked at the current sunspot graphic on the home page and said “aha! finally a well-defined sunspot has appeared!”
then I realized it was a dark speck on my laptop screen. Perhaps a piece of cookie.
Leif Svalgaard (07:15:32) :
Geoff Sharp (06:48:15) :
Apart from you ducking the question I am not too sure. There does not look to be too much information in this area….was hoping with your incredible knowledge you could inform?
I never duck a question. Nothing is happening. Can’t inform on nothing.
And yet a paper you co produced states otherwise….I am confused.
http://www.leif.org/research/ast10867.pdf
Geoff Sharp (16:15:18) :
But the interesting point is that we have a “confirmed” change of rotation of the Sun.
Nobody has ever said that. The TO that Howe shows is not ‘the rotation of the Sun’, no matter how many times you repeat it is.
Do you have a link for the SC23 rotation reanalysis?
Of course. Page 3 of http://leif.org/research/SolarCycleMinima.ppt shows Howe’s re-analysis. Beware that these measurements are difficult.
So,
1) not rotation
2) no good evidence TO has changed, if anything decreased
3) “case like the earth/moon system”: the E/M system works with a one-way coupling that always slow down the Earth, and can never speed the Earth up.
Leif Svalgaard (17:29:39) :
You are all over the place on this one.
First you state:
Reanalysis of MDI data shows a significantly slower TO during solar cycle 23
Then once questioned on the data thats looks weak you state:
no good evidence TO has changed, if anything decreased
When questioned on the solar rotation rate you say there has been none and try to confuse the issue by involving differential rotation, but a paper produced by yourself states in the conclusion:
“A secular deceleration of the mean solar rotation in the 20th
century was found by tracing sunspot groups. This variation
also shows a finer modulation indicating a connection
with the phase of the 11-year solar cycle. In the years 1902
and 1913 we have found possible rotational signatures of
two weak solar activity cycles (Gleissberg minimum). The
rotation velocity residual increased in these years for about
0.4 ◦/day. This is in a qualitative and quantitative agreement
with a similar rotational behaviour during the Maunderminimum.
A qualitatively similar behaviour was also found on
a shorter time scale for the period 1998–2000. As solar activity
was increasing, the equatorial rotation velocity determined
tracing coronal bright points was decreasing (in this
part of analysis monthly values were used).
A dependence of the solar rotation velocity measured by
magnetic tracers and solar activity and interplanetary magnetic
field was found. An interplay between the Reynolds
and the Maxwell stresses is proposed for the interpretation.
As stated by R¨udiger & Hollerbach (2004), the more magnetic
the Sun is, more rigid is its rotation.”
This paper also shows graphs of rotation change and includes a graph of sidereal equation rotation speed changes.
http://www.leif.org/research/ast10867.pdf
You have also had quite a bit do with a paper by J K Lawrence
Rotational quasi periodicities and the Sun – heliosphere connection, where if I am not mistaken they produce fluctuating solar rotation periods determined from the IMF.
On Solarcycle24.com you responded to a question from “atra” on the 4th May (Oz time):
“Is it possible that weak cycles and grand minimums are related to solar rotation, mainly the slowing down of the equatorial rotation?
Is there any data on this?”
Your Answer:
“Whatever data we have suggests that solar rotation is faster when activity is low, i.e. that solar activity slows down solar rotation. E.g. Figure 2 of http://www.leif.org/research/ast10867.pdf”
I find this all very confusing and if the mentioned papers are only taking about differential rotation then they are very badly written and should be considered misleading. “atra’s” question does not look to be addressing differential rotation.
Geoff Sharp (20:30:52) :
You are all over the place on this one.
As you point out the terminology is confusing. And several authors [including some of my co-authors] contribute to the confusion. Some of this is historical. Terms often survive past their ‘sell-by date’. My recent comments were an attempt to cut through the maze and haze and set things straight. Give you the right terminology to use.
Wrong [or sloppy] terminology abounds. E.g. one talks about ‘superrotation’ of the Venusian upper atmosphere, it ‘rotates’ 60 [sixty!] times faster than the solid planet. This is clearly not rotation, but a superfast wind. A current suggested explanation goes something like this: the superrotation is produced by interaction between meridional circulation and planetary-scale waves. Thermally induced waves produce equatorward momentum fluxes in the middle atmosphere, while the planetary-scale pattern of two different gravity and Rossby waves with the same frequency is found to produce the equatorward momentum flux in the lower atmosphere.
Similar processes probably take place in the Sun, except on a much smaller scale [speed-wise, that is].
Leif Svalgaard (22:12:30) :
I am still confused, maybe we need to coin a new phrase to cut thru the haze. I am looking for data on the whole mass of the Sun in relation to rotation speed, how long it takes to do a complete revolution at the equator as viewed from the Sun showing any variance over time….lets call this “Overall Solar Rotation Velocity”.
What type of rotation are you referring to in the paper:
http://www.leif.org/research/ast10867.pdf
A secular deceleration of the mean solar rotation in the 20th
century
Also what type of rotation is shown in the graphs in that paper.
Is the paper by J K Lawrence
Rotational quasi periodicities and the Sun – heliosphere connection, talking about overall solar rotation or something different?
http://arxiv.org/abs/0803.3260v1
Geoff Sharp (23:40:28) :
I am looking for data on the whole mass of the Sun in relation to rotation speed, how long it takes to do a complete revolution at the equator as viewed from the Sun showing any variance over time….lets call this “Overall Solar Rotation Velocity”.
Since most of the solar mass resides in the core, that would be close to the rotation of the core, but since the speed depends on position you have to integrate the rotational profile weighted by mass to get am ‘average’ rotation. Nobody really cares much for what the precise result is, so you won’t find a handy number anywhere.
What type of rotation are you referring to in the paper:
http://www.leif.org/research/ast10867.pdf
The residuals are the deviation from the average rotation period integrated over all latitudes. If the differential rotation was the same over time, this difference would be zero. A larger number means a stronger differential rotation, not really that the whole sun is rotating faster.
Is the paper by J K Lawrence
Rotational quasi periodicities and the Sun – heliosphere connection, talking about overall solar rotation or something different?
That is the ‘recurrence period’ of magnetic activity which might be close to the rotation period at the location where the magnetic field is generated or located. This may not be the same as the rotational period of the non-magnetic parts of the Sun.
Since there is a [historically based] tendency to call all of these ‘rotation’ even if only referring to ‘wind’ speeds, there are fertile grounds for confusion of the ‘uninitiated’. It should be clear from the context what is what, though. To calculate the total angular momentum you integrate the product of mass and speed over all locations. That number will slowly decrease over time [eons] due to magnetic ‘friction’ with the solar wind but cannot otherwise vary, so the precise number is of little interest. An approximate value is easy the get, e.g. as here: http://physics.ucsd.edu/students/courses/fall2002/physics1a/homework/1AHW7Sub.html
Leif Svalgaard (04:44:06) :
I get your drift…overall solar rotation velocity is not something easy to measure.
Geoff Sharp (05:05:01) :
I get your drift…overall solar rotation velocity is not something easy to measure.
Especially not when one mixes concepts and not keep a clear distinction [and many of us are sinners in that regard] between ‘rotation’ and ‘flows’ or ‘winds’.
A recent review of all this is here:
Large Scale Flows in the Solar Convection Zone
Brun, Allan Sacha; Rempel, Matthias
Space Science Reviews, Volume 144, Issue 1-4, pp. 151-173
Publication Date:04/2009
Keywords: convection, rotation, mean flows, magnetism, torsional oscillations
DOI: 10.1007/s11214-008-9454-9
Abstract
We discuss the current theoretical understanding of the large scale flows observed in the solar convection zone, namely the differential rotation and meridional circulation. Based on multi-D numerical simulations we describe which physical processes are at the origin of these large scale flows, how they are maintained and what sets their unique profiles. We also discuss how dynamo generated magnetic field may influence such a delicate dynamical balance and lead to a temporal modulation of the amplitude and profiles of the solar large scale flows.
Leif Svalgaard (09:12:43) :
So have you ever seen an attempt to measure the overall solar rotation velocity?
Geoff Sharp (16:17:00) :
So have you ever seen an attempt to measure the overall solar rotation velocity?
Provided that you can agree to distinguish correctly between rotation and flows, the data exists for that, as helioseismology provides up with the Doppler data needed for this. Since there a [almost] discontinuous changes in the profile it may not may much sense to compute an average, much as it does not make much sense to say that the average temperature on the Moon be computed by averaging the night time temperature and the day time temperature, giving an average result like -10C and then basing your heating/cooling need on that average.
You know the data I am looking for, but I dont expect you to arm the opposition. Computing an average is probably not going to get close, but there will be another method besides helioseismology that may provide the data. Trying to establish a datum line on a viscous surface does seem a challenge.
Maybe I might investigate something a bit more obscure like solar satellite orbit data and search for a trade off etc.
Geoff Sharp (22:10:07) :
You know the data I am looking for, but I dont expect you to arm the opposition.
Of course, I would if I could. That is just basic scientific decency [although according to Paul Vaughan, I not a decent scientist 🙂 ]. But it will be a hard, frustrating slug to search for something that violates physical laws, but then the reward would be commensurate with the misery.
Leif Svalgaard (22:29:56) :
I am just looking for solar rotation data similar to earths LOD measurements. Neither of these violate any physical laws, on the contrary I would have thought.
Geoff Sharp (02:26:56) :
I am just looking for solar rotation data similar to earths LOD measurements. Neither of these violate any physical laws, on the contrary I would have thought.
You stated that your are doing this in a “search for a trade off”. It is the trade off that is the violation. I don’t think you care about what the solar LOD is if it would show no ‘trade off’.
Leif Svalgaard (06:37:15) :
You stated that your are doing this in a “search for a trade off”. It is the trade off that is the violation. I don’t think you care about what the solar LOD is if it would show no ‘trade off’.
You make many assumptions and dont need to make such statements…it does you no credit. The trade off I was talking about was in relation to searching for a LOD type measurement on the Sun. An angular momentum trade off or conservation because of solar rotation change that could occur with a solar satellite as seen with the earth/moon system. I take offense at what you think I care about, contrary to your thoughts I have no barrow to push or life’s work to protect, and only seek knowledge.
Geoff Sharp (07:14:32) :
I take offense at what you think I care about
Fair enough.
Geoff Sharp (07:14:32) :
An angular momentum trade off or conservation because of solar rotation change that could occur with a solar satellite as seen with the earth/moon system.
If you change solar rotation, it would have absolutely no effect on a solar satellite. This is the important point you are ignoring [not missing, as it has been pointed out repeatedly].
Leif Svalgaard (08:07:33) :
If you change solar rotation, it would have absolutely no effect on a solar satellite. This is the important point you are ignoring [not missing, as it has been pointed out repeatedly].
Lets assume the Sun slows its rotation because of friction at the Tachocline…would we not see an increase in the semi-major axis of its satellite?
Geoff Sharp (15:33:43) :
Lets assume the Sun slows its rotation because of friction at the Tachocline…would we not see an increase in the semi-major axis of its satellite?
Only if it is the satellite that is causing the friction, never if the friction is due to, say, tides raised by another planet, e.g. Jupiter
There are two additional problems:
1) the energy available to slow the Sun down by friction is minuscule because the tides are so small and would not be concentrated just at the tachocline if due to planets far away.
2) the friction is always one-way, so you never get a speed-up of the Sun [to make a cycle].
Geoff Sharp (15:33:43) :
Lets assume the Sun slows its rotation because of friction at the Tachocline…would we not see an increase in the semi-major axis of its satellite?
To clarify: if the friction is internal to the Sun [i.e. not caused by planetary tides] then there would be no change in the orbit of the satellite, but the two layers rubbing against one another at the tachocline because there is shear there, would equalize their rotation rates, one would slow down, the other would speed up to maintain constancy of angular momentum. So, the shear and the friction will over time disappear.
Only if it is the satellite that is causing the friction, never if the friction is due to, say, tides raised by another planet, e.g. Jupiter
There are two additional problems:
1) the energy available to slow the Sun down by friction is minuscule because the tides are so small and would not be concentrated just at the tachocline if due to planets far away.
2) the friction is always one-way, so you never get a speed-up of the Sun [to make a cycle].
Leif Svalgaard (16:48:57) :
The area that is not clear to me is: why is it only the satellite that is causing the friction, experiencing the orbit trade off. Your saying the increase in semi-major axis is a result of friction and conservation of angular momentum and not conservation alone?
Geoff Sharp (18:09:44) :
The area that is not clear to me is: why is it only the satellite that is causing the friction, experiencing the orbit trade off. Your saying the increase in semi-major axis is a result of friction and conservation of angular momentum and not conservation alone?
For something to change its speed [a change in speed is acceleration] a force must be applied [Newton’s second law: Force = Mass x Acceleration (F=M a), or a = F/M. No force, no change. The friction provides that force: no friction, no force, no change.
Now, consider a planet [satellite] in orbit, call it A. There is a gravitational force [general relativity aside – Newton is good enough for this] between the Sun [S] and A. Let A raise a tide on the Sun giving rise to another force [at right angle to the gravitational force between S and A] slowing S down and increasing the distance of A. Consider another planet B and let it be much smaller than A [or much farther away]. Its tidal force working at right angles to the gravitational force between S and B will be much smaller than that of A and cause a much smaller friction and thus a much smaller slowdown of S and therefore a much smaller increase of distance to B. In the limit that B is VERY small [a small artificial satellite], the effect on B will be negligible.
The salient point is that the system comprised of S and A is independent from the system comprised of S and B. This may be the sticking point for you. If the above consideration is correct then we can consider the case where Moon did not raise a tide [e.g. if the Moon were much farther away]. The Sun still raises a tide [half of the Moon’s present tide] and there is still friction due to the solar tidal bulge, and that friction will cause the Earth to rotate slower and the Sun to recede [very little] to preserve angular momentum in the Sun-Earth system, but will not cause the Moon to recede any further, because the Moon is no longer tidally coupled to the Earth [remember we considered the case [far in the future] where the Moon had receded to the point of its tides being negligible].
The treatment above was a little bit sloppy, because the mechanism is slightly more complex. The Earth rotates much faster than the Moon revolves so the tidal bulge is actually carried forward [in the sense of Earth’s rotation] and it is the gravitational force on the bulge that slows the Earth. The friction serves only to make the bulge move forward. On the Earth, this is a trivial detail and can be glossed over in a simple explanation. But there is another system where the precise mechanism becomes crucial, and that is Mars and its two satellites Deimos and Phobos. Deimos is the furthest away and its orbital period is longer than Mars’ day, so everything works just as in the Moon-Earth system. The interesting part is that Phobos is so close to Mars that its orbital period is shorter than mars’ day. This means that the bulge will not [as on Earth and Deimos] be carried forward by the faster rotation, but will lag behind, so the Phobos is not moving away from Mars [as Deimos and the Moon from the Earth], but is moving closer to Mars. So in the Martian system, the two satellites behave independently: one moves away and the other moves closer. So, the movement of one does not influence the movement of the other. And that is the crucial point.
You can get a feel for the math behind this by following these lectures:
http://iapetus.phy.umist.ac.uk/Teaching/SolarSystem/Lecture1.pdf
change ‘Lecture1’ to ‘Lecture2’ to get the next one, and so on. Tides are discussed in number 7 and on.
Leif Svalgaard (19:19:56) :
I appreciate your detailed response, and it has set the seed for more questions.
What stood out most was your statement:
The Sun still raises a tide [half of the Moon’s present tide] and there is still friction due to the solar tidal bulge, and that friction will cause the Earth to rotate slower and the Sun to recede [very little] to preserve angular momentum in the Sun-Earth system
I take it you mean the semi-major axis will increase, can you expand on your reasoning here or provide a link that describes the process. The Sun receding is the real meat on the bones in my opinion.
Geoff Sharp (04:17:53) :
I take it you mean the semi-major axis will increase, can you expand on your reasoning here or provide a link that describes the process. The Sun receding is the real meat on the bones in my opinion.
The process is the same as for the Moon. As far is the process is concerned, you can consider the Sun to be a satellite around the Earth. There is not much meat on that bone as the effect is unmeasurably small because the Sun’s mass is so huge. The important point is that [just as with Deimos and Phobos] the tidal effects of the Sun and the Moon are independent. So tides on the Sun raised by Jupiter will not have any effect on the orbit of another planet. Note also that if your satellite is close to the Sun [orbital period less than 27 days] the effect [as for Phobos] goes the other way. Anyway, one more time: tides on the Sun raised by one planet will not have any effect on the orbit of another planet.
Leif Svalgaard (06:36:19) :
I asked the question because there seemed to be 2 schools of thought on the earth/moon system. The one outlined in your referenced lecture notes does not attribute the outward movement of the moon to angular momentum but suggests the forward bulge accelerates the moon which moves it out (which seems opposite to Kepler’s law).
I am not sure if your Martian example is applicable as there are many differences, the only bulge involved would be a very thin atmosphere and the shape of Mars itself. The moons themselves are not spheres and are very small but still we see a fairly big movement in the orbit reduction of Phobos of around 20 meters per century…the numbers dont look right?
I also have an interesting thought experiment re bulges. If we go on the bulge theory (I dont think its generally accepted) eventually over time the earth’s rotation would slow to match the lunar period which would only leave the Sun as a tidal mechanism. The earth would slow further putting the moon in a faster orbit than the rotation of earth which would generate a bulge behind the moon thus dragging the earth into a faster rotation and equalizing again. So maybe there is a possibility of tides increasing rotation?
Geoff Sharp (07:59:27) :
I asked the question because there seemed to be 2 schools of thought on the earth/moon system. The one outlined in your referenced lecture notes does not attribute the outward movement of the moon to angular momentum but suggests the forward bulge accelerates the moon which moves it out (which seems opposite to Kepler’s law).
There is only one school of thought. The ‘angular momentum’ is not a mechanism per se, but a constraint on what can happen [whatever process works must keep the AM the same]. Only a force can change anything. And that the Moon moves out when accelerated is what is supposed to happen. Think of the space station having to fire its engines now and then to attain a higher orbit, whenever atmospheric drag has lowered it. If you want to even higher, e.g. to the Moon, you have to let the engine burn a lot longer.
The Martian example: tidal effects work no matter what shape the bodies have and they don’t have to be fluid or gases. The effect is so large because the moons are so close. If you move our Moon in to 1/10th the distance, the tidal effects go up thousand fold as they depend on the cube of the distance [which is why even mighty Jupiter raises such a minuscule tide on the Sun].
I am not sure if your Martian example is applicable as there are many differences, the only bulge involved would be a very thin atmosphere and the shape of Mars itself. The moons themselves are not spheres and are very small but still we see a fairly big movement in the orbit reduction of Phobos of around 20 meters per century…the numbers dont look right?
I also have an interesting thought experiment re bulges. If we go on the bulge theory (I dont think its generally accepted) eventually over time the earth’s rotation would slow to match the lunar period which would only leave the Sun as a tidal mechanism. The earth would slow further putting the moon in a faster orbit than the rotation of earth which would generate a bulge behind the moon thus dragging the earth into a faster rotation and equalizing again. So maybe there is a possibility of tides increasing rotation?
If we go on the bulge theory (I dont think its generally accepted)
the only one there is and accepted by all, except pseudo-scientist peddling stuff on the Internet 🙂
eventually over time the earth’s rotation would slow to match the lunar period which would only leave the Sun as a tidal mechanism. The earth would slow further putting the moon in a faster orbit
Once the Sun is the only tidal mechanism, any further slowing of the Earth will have no effect on the Moon. I think I may have failed completely in getting that across; perhaps one more time: tides raised by one body will not have any effect on the orbit of another body.
So maybe there is a possibility of tides increasing rotation?
I think I said that several times. If the orbital revolution is faster than rotation, it goes the other way [Phobos], but in the solar system all planets have periods greater than 27 days. Interesting enough, in the early solar system when the planets were forming, friction between a planet and the solar system protoplanet disk caused the planet to loose energy and migrate closer to the Sun. Some exoplanets are very close to their suns, not because they formed there [it is too hot], but because they moved there by tidal forces. Tides are very important in the universe and are well-understood. The crucial point is that one must calculate what their sizes are to establish how important they are for any particular case, and for the present solar system, the tides raised by the planets are just too small to have any effect.
Preview would help…
Geoff Sharp (07:59:27) :
I asked the question because there seemed to be 2 schools of thought on the earth/moon system. The one outlined in your referenced lecture notes does not attribute the outward movement of the moon to angular momentum but suggests the forward bulge accelerates the moon which moves it out (which seems opposite to Kepler’s law).
There is only one school of thought. The ‘angular momentum’ is not a mechanism per se, but a constraint on what can happen [whatever process works must keep the AM the same]. Only a force can change anything. And that the Moon moves out when accelerated is what is supposed to happen. Think of the space station having to fire its engines now and then to attain a higher orbit, whenever atmospheric drag has lowered it. If you want to even higher, e.g. to the Moon, you have to let the engine burn a lot longer.
The Martian example: tidal effects work no matter what shape the bodies have and they don’t have to be fluid or gases. The effect is so large because the moons are so close. If you move our Moon in to 1/10th the distance, the tidal effects go up thousand fold as they depend on the cube of the distance [which is why even mighty Jupiter raises such a minuscule tide on the Sun].
If we go on the bulge theory (I dont think its generally accepted)
the only one there is and accepted by all, except pseudo-scientists peddling stuff on the Internet 🙂
eventually over time the earth’s rotation would slow to match the lunar period which would only leave the Sun as a tidal mechanism. The earth would slow further putting the moon in a faster orbit
Once the Sun is the only tidal mechanism, any further slowing of the Earth will have no effect on the Moon. I think I may have failed completely in getting that across; perhaps one more time: tides raised by one body will not have any effect on the orbit of another body.
So maybe there is a possibility of tides increasing rotation?
I think I said that several times. If the orbital revolution is faster than rotation, it goes the other way [Phobos], but in the solar system all planets have periods greater than 27 days. Interesting enough, in the early solar system when the planets were forming, friction between a planet and the solar system protoplanet disk caused the planet to loose energy and migrate closer to the Sun. Some exoplanets are very close to their suns, not because they formed there [it is too hot], but because they moved there by tidal forces. Tides are very important in the universe and are well-understood. The crucial point is that one must calculate what their sizes are to establish how important they are for any particular case, and for the present solar system, the tides raised by the planets are just too small to have any effect.
Leif Svalgaard (09:12:12) :
“eventually over time the earth’s rotation would slow to match the lunar period which would only leave the Sun as a tidal mechanism. The earth would slow further putting the moon in a faster orbit…”
Once the Sun is the only tidal mechanism, any further slowing of the Earth will have no effect on the Moon.
Perhaps a clarification: as long as the Sun is the only tidal mechanism this holds, but if you slow down the Earth further, the Earth’s rotation and the lunar period would no longer match and lunar tidal effects would pick up again. One has to be VERY precise in these things.
Leif Svalgaard (09:12:12) :
If we go on the bulge theory (I dont think its generally accepted)
the only one there is and accepted by all, except pseudo-scientists peddling stuff on the Internet 🙂
The reason I said not generally accepted is I dont think the science is settled on this one. The bodies responsible for collecting LOD measurements seem to be very non committal on the causes of slowing process mentioning external tides and other internal processes. Tidal friction due to continents is mentioned on several websites. This from the USNO
http://maia.usno.navy.mil/eop.html
” The secular variation of the rotational speed seen by the apparently linear increase in the length of the day is due chiefly to tidal friction. The Moon raises tides in the ocean diminishing the speed of rotation. This effect causes a slowing of the Earth’s rotational speed resulting in a lengthening of the day by about 0.0015 to 0.0020 seconds per day per century.
The irregular changes in speed appear to be the result of random accelerations, but may be correlated with physical processes occurring on or within the Earth. These cause the length of the day to vary by as much as 0.001 to 0.002 seconds. Irregular changes consist of “decade fluctuations” with characteristic periods of five to fifteen years as well as variations which occur at shorter time scales. The decade fluctuations are related apparently to processes occurring within the Earth. The higher frequency variations with periods less than two years are now known to be related largely to the changes in the total angular momentum of the atmosphere.
Periodic variations are associated with periodically repeatable physical processes affecting the Earth. Tides raised in the solid Earth by the Moon and the Sun produce variations in the length of the day with amplitudes on the order of 0.00005 seconds and with periods of 18.6 years, 1 year, 1/2 year, 27.55 days, 13.66 days and others. A standard model including 62 periodic components, can be employed to correct the observations for tidal effects. Changes in the total angular momentum of the atmosphere have also been shown to be correlated with changes in the length of the day.
The rotational speed of the Earth remains essentially unpredictable in nature due to incompletely understood variations. Because of this, astronomical observations continue to be made regularly with increasing accuracy, and the resulting data are the subject of continuing research in the field. ”
Leif Svalgaard (09:36:05) :
Perhaps a clarification: as long as the Sun is the only tidal mechanism this holds, but if you slow down the Earth further, the Earth’s rotation and the lunar period would no longer match and lunar tidal effects would pick up again. One has to be VERY precise in these things.
Perhaps this might be one area where a tidal effect from one body can have a knock on effect to another body, the moon would have acceleration and orbit changes because of the Sun’s tide. But my main point is that you could get a two way result because of friction, the earth could increase and decrease its rotation because of tidal effects. But having said that, both of my scenario’s are secondary processes.
Your earlier point re AM is more a background process that must be conserved and only forces can make actual changes ie rotation etc is interesting. We have discussed friction but there must be other forces at play. Looking at elliptical orbits and orbit velocity changes which result from gravity alone is one area, and what happens with the movement of the Sun in its orbit and how angular momentum must be conserved in relation to the bodies orbiting the Sun is an intriguing question that perhaps has more answers to come.
Geoff Sharp (17:02:34) :
The reason I said not generally accepted is I dont think the science is settled on this one. The bodies responsible for collecting LOD measurements seem to be very non committal on the causes of slowing process mentioning external tides and other internal processes.
As far as external tides are concerned the science was settled 100 years ago. There are internal changes to the Earth’s moment of inertia due to movements of magma inside the Earth, and to friction at the interface between the core and both the mantle and the inner core. All of this are just details that becomes observable as our ability to measure these things increase. They do not reflect uncertainty in the physical underpinning of these phenomena. It is like, because we can’t predict the weather a year from today does not mean that the physical laws are incomplete or unknown.
But my main point is that you could get a two way result because of friction, the earth could increase and decrease its rotation because of tidal effects.
Don’t cling to this one because for all current planets at this time friction in the Sun is a one-way process. And it is not your point, I explained to you.
Your earlier point re AM is more a background process that must be conserved
It doesn’t matter in which direction the vectors point. Our physical understanding of this is solid and three hundred years old. If you postulate other [unknown] physical laws to be operating, anything goes, of course, but that was the hard slug I was referring to. but there must be other forces at playwell, none we know of.
It all boils down to this: there are only three mechanisms within known physical laws that can transfer angular momentum:
1) tides with friction
2) magnetic torques due to stretching of file lines
3) the Poynting-Robertson effect caused by absorption [from one direction] and re-emission [in all directions] of light.
All of these are much too small at the present time to have any measurable effect on the Sun [for 1 and 2] or planets [3].
If one wants to stick to the correlations being caused by angular momentum transfer, one must postulate that in spite of these shortcomings it somehow works anyway. This is an acceptable position as long as it is not coupled with a claim that these things are science-based.
Leif Svalgaard (19:03:57) :
As far as external tides are concerned the science was settled 100 years ago.
I have seen some some questions re the bulge theory, if we go back in time and reverse the current moon recession rate it would enter the destruction zone in 1.2 billion years. If the earths slowdown was purely based on tidal friction the recession rate would be slower when there was only one continent etc.
It all boils down to this: there are only three mechanisms within known physical laws that can transfer angular momentum:
1) tides with friction
2) magnetic torques due to stretching of file lines
3) the Poynting-Robertson effect caused by absorption [from one direction] and re-emission [in all directions] of light.
Dont forget Kepler’s 2nd Law.
Leif Svalgaard (19:03:57) :
If one wants to stick to the correlations being caused by angular momentum transfer, one must postulate that in spite of these shortcomings it somehow works anyway.
That’s a big statement…..the message is getting through.
Geoff Sharp (20:05:37) :
I have seen some some questions re the bulge theory, if we go back in time and reverse the current moon recession rate it would enter the destruction zone in 1.2 billion years.
Stop squirming 🙂 These calculations that depend on assuming that the boundary conditions were the same are not very precise. The point is, we know how this works. To use theat knowledge to accurately predict things we need data, which we don’t have. Like predicting the weather: we know the physics, the mechanisms, ect, but need the data.
Dont forget Kepler’s 2nd Law.
I’m not. It has nothing to do with transfer of Angular Momentum and friction, etc. Kepler’s 2nd law states [equivalently] that the orbital AM of a planet is constant, so when the planet is closer to the Sun, it has to move faster [AM=distance*speed]
Geoff Sharp (22:06:57) :
“If one wants to stick to the correlations being caused by angular momentum transfer, one must postulate that in spite of these shortcomings it somehow works anyway.”
That’s a big statement…..the message is getting through.
Well, it’s you making that statement. And there is nothing wrong with that, once it is admitted that that is a violation of physical laws as we know them [and that one therefore must assume there are unknown laws controlling this, thus appealing to such unknowns].
Leif Svalgaard (22:24:08) :
Stop squirming 🙂 These calculations that depend on assuming that the boundary conditions were the same are not very precise. The point is, we know how this works. To use theat knowledge to accurately predict things we need data, which we don’t have. Like predicting the weather: we know the physics, the mechanisms, ect, but need the data.
The boundary conditions might be favorable…if we go back the moon is closer and the bulge bigger…that’s the problem.
Dont forget Kepler’s 2nd Law.
——————————————————-
I’m not. It has nothing to do with transfer of Angular Momentum and friction, etc. Kepler’s 2nd law states [equivalently] that the orbital AM of a planet is constant, so when the planet is closer to the Sun, it has to move faster [AM=distance*speed]
That’s my point…transfer of angular momentum without friction.
Geoff Sharp (07:27:34) :
The boundary conditions might be favorable…if we go back the moon is closer and the bulge bigger…that’s the problem.
Why is that a problem? The exact size of the bulge depends on things [boundary conditions] we don’t know and can only estimate.
Kepler’s 2nd law:
That’s my point…transfer of angular momentum without friction.
You must be particularly think today. Kepler’s 2nd law specifies that the AM cannot change. Kepler didn’t know this, but Newton knew. You are back to Kepler as if Newton and physicist since him never existed.
Leif Svalgaard (08:34:05) :
You must be particularly think today. Kepler’s 2nd law specifies that the AM cannot change. Kepler didn’t know this, but Newton knew. You are back to Kepler as if Newton and physicist since him never existed.
If you want to ignore the transfer of orbit speed to a planet through AM conservation, do so. But remember the Sun’s velocity changes too as it takes its 2 distinctively different paths, this may not turn out to be chicken feed.
Geoff Sharp (23:56:29) :
But remember the Sun’s velocity changes too as it takes its 2 distinctively different paths, this may not turn out to be chicken feed.
It seems you have not learned anything at all.
Leif Svalgaard (00:49:06) :
It seems you have not learned anything at all.
I must be in the wrong universe 🙂
Geoff Sharp (10:58:57) :
I must be in the wrong universe 🙂
No, just ignorant about physics and statistics and basic data analysis and about how this Universe works and unwilling to learn.
Leif Svalgaard (11:41:45) :
No, just ignorant about physics and statistics and basic data analysis and about how this Universe works and unwilling to learn.
Considering I showed you that tidal friction can cause acceleration and deceleration of a planetary body, after you saying for months its only one way, I consider myself capable….I hope you are learning something.