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"All Quiet Alert" Issued For the Sun
Posted by
kdawson
on Tue Oct 16, 2007 03:04 PM
from the that-would-fix-global-warming dept.
from the that-would-fix-global-warming dept.
radioweather writes "The phrase sounds like an oxymoron, and maybe it is, but the sun is extremely quiet right now, so much in fact that the Solar Influences Data Center in Belgium issued an unusual 'All quiet alert' on October 5th. Since then the sunspot number has remained at zero — solar cycle 24 has not yet started. There are signs that the sun's activity is slowing. The solar wind has been decreasing in speed, and this is yet another indicator of a slowing in the sun's magnetic dynamo. There is talk of an extended solar minimum occurring. There are a number of theories and a couple of dozen predictions about the intensity solar cycle 24 which has yet to start. One paper by Penn & Livingstonin in 2006 concludes: 'If [trends] continue to decrease at the current rate then the number of sunspots in the next solar cycle (cycle 24) would be reduced by roughly half, and there would be very few sunspots visible on the disk during cycle 25.' We'll know more in about six months what the sun decides to do for cycle 24."
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Solar Cycle 24 Has Started 258 comments
radioweather writes "Solar physicists have been waiting for the appearance of a reversed-polarity sunspot to signal the start of the next solar cycle. As of Friday, that wait is over. A magnetically reversed, high-latitude sunspot emerged on the surface of the sun. Just a few months ago, an 'All Quiet Alert' had been issued for the sun. This reversed-polarity sunspot marks the beginning of the sun's return back to Solar Maximum.
Solar Cycle 24 has been the subject of much speculation due to competing forecasts on whether it will be a highly active or a quiet low cycle. If it is a low cycle, it may very well be a test of validity for some CO2 based global warming theories. Only time will tell."
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Sunspot numbers (Score:5, Informative)
Here is a nice graph that shows sunspot data from 1620 to 2000
http://spaceweather.com/glossary/sunspotnumber.html [spaceweather.com]
We can see that this isn't anything new.
BTW - If you are interested in Auroras, keep watch on the 18th-19th. We are about to get hit with a solar wind stream.
Quick! Alert the scientific community! (Score:5, Funny)
We must take immediate and drastic steps to fight Global Darkening!
Maybe we can get that Kim Stanley Robinson person to write a book? 70 Days of Night?
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Re:Quick! Alert the scientific community! (Score:5, Informative)
So, if you want to draw a conclusion on this, if the sunspots are low, and the earth is still getting hotter... that means we really are getting hotter (disclaimer: sunspot numbers go up and down all the time in regular cycles. Global Warming is a very long term trend that is going up over several sunspot cycles. You can't really draw a conclusion on global warming based on a short term sunspot activity. I'm just saying, if you really wanted to draw one, that'd be it).
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Re:Quick! Alert the scientific community! (Score:5, Funny)
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Re: (Score:3, Funny)
Re: (Score:3, Interesting)
Since sunspots are dark it might be expected that more sunspots lead to less solar radiation and a decreased solar constant. However, the surrounding areas are brighter and the overall effect is that more sunspots means a brighter sun. The variation caused by the sunspot cycle to solar output is relatively small, of the order of 0.1% of the solar constant (a peak-to-trough range of 1.3 W m-2 compared to 1366 W m-2 for the average solar constant)[2][3]. This range is slightly smaller than the change in radiative forcing caused by the increase in atmospheric CO2 since the 18th century[4]. During the Maunder Minimum in the 17th Century there were hardly any sunspots at all. This coincides with a period of cooling known as the Little Ice Age. It has been speculated that there may be a resonant gravitational link between a photospheric tidal force from the planets, the dominant component by summing gravitational tidal force (75%) being Jupiter's with an 11 year cycle[5].
http://en.wikipedia.org/wiki/Sunspot [wikipedia.org]
Re:Quick! Alert the scientific community! (Score:5, Informative)
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Re: (Score:3, Informative)
Sunspots correspond to the amount of magnetic activity, which is the major driving force behind activity (flares, CMEs, filament eruptions,
(I work in the field)
Re: (Score:3, Informative)
Re: (Score:3, Interesting)
And in the last 10 years that's started to reverse. [straightdope.com]
(This time with a working link.)
Re:Quick! Alert the scientific community! (Score:5, Informative)
Global Darkening [wikipedia.org] is actually a moderate problem, though it's actually caused by particulate pollutants in the atmosphere, not sunspots. The amount of light energy reaching the Earth over the last hundred years has been dropping slowly, until recently, when it started going up again -- as dirty pollution has been regulated and replaced with "cleaner" CO2 pollution.
There's a lot of concern among climatologists that global darkening has been masking the effects of global warming, and that as solar radiation on the surface goes up again, the effects of global warming might come upon us more severely and faster than our previous estimates.
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Re:Sunspot numbers (Score:5, Insightful)
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Re:Sunspot numbers (Score:5, Funny)
The other side would be dead.
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That's the Maunder Minimum (Score:5, Interesting)
I don't think the 'experts' necessarily know anything more at this point, either; just a few years ago, NASA was predicting that the next cycle would be the strongest ever, and that got a lot of people (especially folks that do a lot of shortwave/HF radio) very excited. Now, it looks like we may have a very small cycle, or no cycle at all -- it's anybody's guess.
The dead spot on some sunspot charts from 1650-1700 is called the "Maunder Minimum". During that period, rather than talking about sunspots, observers of the day would write about the appearance of a particular sunspot (very much singular!). Unfortunately, the data prior to the beginning of the minimum is pretty sparse, and exactly when it started is under some dispute.
There was also another minimum in the early 19th century, called the Dalton Minimum, although it wasn't as severe and it only lasted about 25 years.
So that's two minima separated by a 150-year gap. But at 150 years after the 1800 minimum, rather than another minimum, we actually get a maximum in 1950. There's just not enough historical data to make a good prediction, because we don't know how complex the cycle is. But it's clearly more complex than just 11 years.
I can't find a link to it online, but I heard a talk recently about a group that was using geological evidence to try and track the sunspot cycle further back than we have human observations. Not sure quite what the method is, or if it's yielded any results. But that would certainly be interesting, if you could get some real historical perspective instead of the piddling 7 centuries (at most) that you can find written records of. That might give us some idea of what's been going on, on very long timescales, as well as perhaps filling in the gaps in the historical record in more recent times (not sure what kind of resolution you can get).
To use a water analogy, the 11-year cycles might be waves lapping at the shore, but there might be scores of other forces acting on them at higher levels, like tides, wind, and the seasons, all on vastly different time-scales.
All in all, for something that we spend the majority of our waking lives under, our understanding of the sun is surprisingly poor. Particularly given how much modern technology (radio communications is the obvious one, but there are others) can be affected by the solar cycle, it seems to be ignored until it does something unexpected.
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Re:That's the Maunder Minimum (Score:4, Insightful)
The problem is, of course, trying to model this in a meaningful way - thanks to Fourier transforms we know that you can build any given pattern out of a sufficiently large collection of cyclic processes, which makes these cycles upon cycles upon cycles feel a bit iffy to me. Feels much more like a chaotic process with long periods of stable equilibrium, which means that while cycles may be useful for general short-term work, their predictive power is always hampered by the fact that the system may abruptly change in unpredictable ways.
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Re:That's the Maunder Minimum (Score:4, Insightful)
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Re:That's the Maunder Minimum (Score:5, Insightful)
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Re:That's the Maunder Minimum (Score:5, Funny)
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Re:That's the Maunder Minimum (Score:5, Funny)
This message brought to you by the Society for the Brutal Abuse of Misleading Statistics.
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Selective perception (Score:3, Insightful)
no sunspots huh? (Score:3, Funny)
Re: (Score:3, Interesting)
Specifically, at 11 years since the last solar minimum. And 22 years since the one before that. And 33 years since the one before that.
Meanwhile, as you say, the globe warms up.
Re:no sunspots huh? (Score:4, Insightful)
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Re: (Score:3, Informative)
Greenhouse gases include in the order of relative abundance water vapor, carbon dioxide, methane, nitrous oxide, and ozone. (http://en.wikipedia.org/wiki/Greenhouse_gas)
The major greenhouse gases are water vapor, which causes about 36-70% of the greenhouse effect on Earth (not including clouds) ((http://en.wikipedia.org/wiki/Greenhouse_gas))
Re:no sunspots huh? (Score:4, Informative)
Water vapor tends to be rather self-regulating on a very short timescale. It has this tendency to saturate and condense out of the atmosphere during a phenomenon we call "rain". It also can form clouds which may or may not increase albedo and lead to cooling. It can also form snow cover and increase albedo and lead to cooling. Additionally, owing to it's very short mean lifetime in the atmosphere, it tends to have very localized effects on weather.
To put it simply, water vapor tends to track the global climate rather than set it. If there were no other greenhouse gasses the Earth would have frozen into a snowball long ago (and it actually has done this before in Earth's history). Research tends to show water definitely provides feedback mechanisms which can amplify the effects of other forcings, but it is too volatile to be the driving factor all on its own.
Really, the other major greenhouse gas is methane, which is also increasing in the Earth's atmosphere (albeit not as quickly). It has a much shorter lifetime than CO2 does, so it tends not to accumulate without a constant source (which is a good thing). There is some evidence that the rise of agriculture may have had some impact on global climate thousands of years ago. Essentially the cultivation of rice and domestic animals are both non-negligible sources of methane which is extremely potent as a greenhouse gas, but in this case the warming was likely much more moderate than the current trend.
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Re:no sunspots huh? (Score:5, Informative)
Yes, and yet no. CO2 sources/sinks are not purely temperature dependent, unlike water. Yes, the ocean is a huge temperature sensitive repository of CO2, but carbonate rocks and volcanos, not so much. Many of the large changes in CO2 concentration that correlate with climate tend to also correlate with other events in the geologic record (i.e. periods of increased volcanic activity, snowball earth, mountain uplift, etc.). So to answer you and the first response to you, CO2 is both the cause and the effect. If you could magically raise the temperature of the oceans by 10 degrees, yes, you'd release a lot of CO2 and the opposite if you lowered it. However, the total amount of CO2 the ocean can dissolve is rather small compared to the total amount of potential CO2 contained in the geologic carbon cycle (i.e. not just the highly mobile part contained in biomass and oceans).
On short time scales you can ignore the long timescale sources/sinks and just consider the ocean/biosphere/atmosphere CO2 cycle as oscillating about some equilibrium. What's happening here is the long timescale sources/sinks are slowly nudging the equilibrium of the system. What we're currently doing at the moment is releasing massive quantities of trapped carbon that had been removed from the system over millions of years. As a byproduct we're nudging up temperatures globally which are in turn altering the equilibrium states of the highly mobile parts of the system.
If you look at it purely from a standpoint of carbon budgeting it becomes pretty clear we have to be having some impact with the amount of carbon we've returned to circulation over the past 150 years. The greater sources/sinks operate on much slower timescales, and we've effectively put more carbon in circulation. Arguing over whether CO2 is a cause or an effect is kind of a moot point. It's both.
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Re: (Score:3, Informative)
Obviously (Score:5, Funny)
Re:Obviously (Score:4, Informative)
Nice flamebait. In response I'd like to point out the following.
a)There are direct measurements of incoming solar radiation, making all questions as to if we understand the sun irrelevant. We know that the incoming energy has not changed enough to continuously accelerating warming ( in fact, even while incoming radiation has decreased the earth has kept warming quicker and quicker).
b)Satelites sweep out the entire earth's surface measuring incoming and outgoing radiation. This has been going on for some time now. Surprise surprise, the main change is a major reduction in light leaving the earth at wavelengths which correspond to the fringes in CO2's absorption spectrum ( the peaks have saturated already ).
c)Analysis of the ratio of C14 to C12 has confirmed that a huge fraction of the increased CO2 concentration is from a fossil origin. The remainder is believed to be due to deforestation.
d)The oceans have been absorbing more and more CO2 which lowers the sea water pH, leading to "ocean acidification". This is a well documented problem, so the oceans emitting CO2 due to increased solar radiation is ruled out as a cause of recent warming.
e)We know to great detail how much CO2 ( and other greenhouse gases) we have emitted. Since the only other fossil source of carbon is volcanic and geological activity, this together with the C12/C14 analysis tells us volcanos are not to blame. This is also in agreement with our present understanding of geology.
So, in summary:
a)We know the change in radiative forcing is due to greenhouse gases.
b)We know the major amount of extra CO2 is from fossil sources.
c)We know we emit CO2 much more rapidly than volcanos and geologic activity.
You are arguing against the facts, I imagine that is why you insist on resorting to sarcasm and bad jokes rather than addressing the issue at hand.
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Re:Obviously (Score:5, Interesting)
Previously, when humans had little impact, the earth's climate did indeed vary according to solar cycle variations. That, however, does not appear to be the cause now. In particular, the earth has continued to warm at accelerating rates even while solar output has decreased. While being at a high solar activity as compared to a long time before today could perhaps explain some warming, it cannot explain why this warming is accelerating even while solar input decreases. Rather one would expect the rate of warming to decrease as the earth gets hotter, since higher temperatures should result in a greater amount of radiation being emitted by the earth.
The present theory is roughly as follows:
1)Warming from increased solar output causes increased CO2 release from the oceans.
2)The extra CO2 blocks outgoing infrared radiation
3)The shift in radiative forcing gives rise to more warming, resulting in ice-age termination.
It is worth noting that the oceans are presently absorbing a lot of CO2, leading to ocean acidification. Thus while oceans warming due to increased solar activity causes the CO2 spike under ice-age termination, this is not what is happening today.
As I mentioned above the oceans are net-absorbers of CO2 at the moment, leading to ocean acidification as the CO2 is transformed into carbonic acid when it dissolves in water. This is in contrast to ice-age termination where oceans are believed to emit a lot of CO2 due to solar cycle variations. In shallow waters this is actually causing a lot of problems since many marine habitats are sensitive to changes in the pH of the water, and the acidification could kill important parts of the ecosystem.
Plants also release a lot of CO2 when they die, but they also absorb the same amount as they grow, so unless you permanently kill them and prevent new ones from growing, the overall emission will be nil. I can't comment on the 6% figure as it doesn't say what it is talking about. Is it perhaps gross CO2 emitted before reabsorption is taken into consideration? Both the oceans and plants emit a lot of CO2, but they absorb even greater amounts, so if you fail to account for the absorption you may arrive at very low amounts of CO2 emitted by humans, while in reality the net emission is largely due to human activities. Methane is indeed an important greenhouse gas, but we emit CO2 in much larger quantities, making it overall more important as far as emissions are concerned.
As I mentioned before, we have satelite measurements of outgoing radiation, and detailed measurements of the CO2 and Methane absorption spectrum, and this tells us that CO2 is by quite a large margin the most important of our emissions as far as warming is concerned ( thou the other gases have an impact as well ). Also, as C-14 decays with a very long half-life fossil carbon contains significantly less C-14 than carbon from plants and the oceans, and this shows up in CO2 concentration measurements. Following nuclear bomb tests inthe 60ies the overall C-14 concentration spiked. This concentration has rapidly declined, despite C-14's very long halflife, suggesting that large quantities of C-14 has been absorbed while C-12 has been emitted. The C-14 concentration, in combination with the records of our fossil emissions, therefore allows one to estimate how much of the increase in atmospheric CO2 is from fossil sources and how much is from plants and the oceans. It appears the vast majority is caused by humans.
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Simple (Score:4, Funny)
Re: (Score:3, Funny)
Re:Simple (Score:4, Informative)
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Sum it up for me (Score:4, Funny)
Layman's terms? (Score:5, Funny)
Re:Layman's terms? (Score:4, Funny)
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Re:Layman's terms? (Score:5, Funny)
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Re: (Score:3, Funny)
> I'm just a software geek. I know nothing of this "sun" you speak of.
It's another name for the NYF, i.e., the Nasty Yellow Face that appears periodically in the Really Big Room. It's also called the "Burning Face", the "Great Yellow Disc", "Sol", "Masaka", or "Daystar".
In some ways it's a very powerful monster, but in practice it's not a very important one, because there's no need to ever defeat it (if that's even possible). Mostly you ca
ZOMGS! (Score:4, Funny)
try to keep on its good side (Score:5, Funny)
Please stop anthromorphising astonomical bodies. It just makes them angry.
Maybe God's dog peed on it? (Score:3, Funny)
Maybe the Sun is confused... (Score:4, Funny)
A: 42!
It cannot be a coincidence that this magical number popped up here as well. The Sun needs some time to find itself before it decides what to do for the next quart^H^H^H^H^H solar cycle.
Re: (Score:3, Informative)
In this case, you can.
Notice any kind of pattern here? [wikipedia.org]
Re: (Score:3, Informative)
For the first 18 years of my life, I never went into a pub.
The next 20 years of my life I was in there every weekend, for 3 days.
Am I in the pub now ? Please, enlighten me. And bear in mind that the sun has a lot longer life cycle than me. (and I have access to the net anywhere due to 3G telephony).
Re:So in other words.. (Score:4, Funny)
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Re:Holy crap goreman! (Score:4, Funny)
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Re: (Score:3, Funny)
Given that the Sun is itself a large ball of incandescent gas, a gigantic nuclear furnace in which hydrogen is built into helium at a temperature of millions of degrees, and on the surface of which flares and eruptions with the energy of millions of times the entire nuclear arsenal of the planet Earth go off more or less daily, I'd say it's a pretty damn noisy place all the time.
Re:Let me be the first to say... (Score:5, Insightful)
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Re: (Score:3, Interesting)
completly ignoring some facts:
The sun has been experiencing a cooling trend over the last 14 or so years.
Mars is farther away from the sun then earth, and as such isn't impacted by the sun as much. This means mars should not be warming at the same rate in fact, I believe it should be at about 1/4 the impact.
Ignores Mars's dust storm cycle.
Ignores the thinner atmosphere of mars.
This data is data that is cherry picked out of a me
Re:Oh really? (Score:5, Funny)
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