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"All Quiet Alert" Issued For the Sun
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."
Here is a nice graph that shows sunspot data from 1620 to 2000
http://spaceweather.com/glossary/sunspotnumber.html
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.
It could be worse, it could be Monday.
I see you, and several others in the comments, making connections to sunspots and global warming. There really isn't one, or rather, it's the opposite of what you'd think. The more sunspots the sun has, the hotter it gets. Indeed a prolonged period of low sunspot activity is one of the (unproven, competing) theories on what caused the Little Ice Age.
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).
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.
In this case, you can.
Notice any kind of pattern here?
Real Daleks don't climb stairs - they level the building.
Bollocks !
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).
Sunspots are local areas of cooling on the solar surface. However, a less immediately obvious but highly significant factor is that the area around sunspots is warmer than the natural solar temperature. The net result is an increase in total solar output during times of high sunspot activity. Thus there is a positive correlation between sunspot activity and the energy which is delivered to earth. I'm lazy and can't immediately find a better reference than the relevant Wikipedia page, but I'm sure someone with more diligence could dig up something better.
I know you're joking, but there really IS a "Global Darkening" phenomenon, at least according to THIS episode of NOVA.
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))
ok so the 'water vapor picture' is not clear but the fact the earths oceans can with a change a few tenths of a degree soak up or spew out more co2 than man can produce in a decade does not render co2 questionable? H2O is a bigger factor in global warming than co2, its a fact... They both happen to be naturally occurring gases one just has a worse publicist..
Global Darkening 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.
Don't blame me, I voted for Baltar.
Sunspots are areas of intense magnetic field concentration that suppress local convection in the area, and are thus are relatively cooler and darker than the surrounding area.
...).
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)
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.
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.
Six Sigma is used by a lot large Companies usually in manufacturing process. It is basically a method to insure their product meet a particular quality level. So you make your process in a way that the variation in your products is so tight that the probability that there will be a defective product is 6 standard deviation from the mean. Unfortunately a lot of companies with PHB usually who left GE tried implement it in other segments of business and cause huge overhead massive training cost and benefited nothing because the process is only good for manufacturing, not things that deal with people like service. Six Sigma Training usually takes a good amount of work to become certified, and more work for it to be implemented. The joke was attended that sun spots (which are cooler areas of the sun) are caused from errors occurring the fusion. So by taking 6 sigma training they will reduce the number of errors thus relieving sun spots. At the time I thought it was funny... But I was working in a company that was use to be GE a couple months ago.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
I'm assuming when you state that the 'sun is closer during the winter' that you're talking about Earth's orbital eccentricity (non-circular orbit) resulting in the entire planet being about 5 million kilometres closer to the sun during winter. Living in the northern or southern hemisphere would make no difference.
If however you're talking about Earth's rotatational axis then you might want to look at your facts again. Earth axial tilt is ~23degrees which during summer means the North pole is tilted towards the sun, resulting in the northern hemisphere being (on average) closer to the sun.
Wish there was a -1 slightly-wrong tag. Some posts just deserve it. [/joke - but you did ask for it!]
As an aside, just thought I'd mention that the eccentricity results in Earth being about 2 degrees cooler during perihelion (closest point during orbit).
Windows in 6 Bytes (IA-32) : 90 90 90 90 CD 19
You might want to rephrase that or look at the facts again.
I'm assuming when you state that the 'sun is closer during the winter' that you're talking about Earth's orbital eccentricity (non-circular orbit) resulting in the entire planet being about 5 million kilometres closer to the sun during winter. Living in the northern or southern hemisphere would make no difference.
It makes all the difference in (either half of) the world!
To be absolutely clear. The perhelion currently occurs around the begining of January. In the nothern hemisphere January is in winter, whereas in the southern hemisphere January is in summer. The Aphelion occurs around the begining of July. In the southern hemisphere July is in winter, whereas in the northern hemisphere July is in summer. Thus "[i]f you live in the northern hemisphere the sun is closer during the winter than during the summer." Conversely if you live in the southern hemisphere the sun is closer during summer than it is during winter. Can you now understand what the OP wrote, and why it is correct?
That being said, Earth's orbit is only slightly elliptical, so the difference (and climatic effects) between perhelion and aphelion is slight. By contrast the effects are significant on planets (eg. Mars) which have greater eccentricity.
Better to be despised for too anxious apprehensions, than ruined by too confident a security. --Edmund Burke
According to http://www.census.gov/ :
WORLD 2007 Total, all ages 6,602,236,753
According to http://www.math.hawaii.edu/~ramsey/People.html :
[...] one estimates that 96,100,000,000 people have lived on the earth.
The dead outnumber the living roughly 15 to 1.
So chances are you are already dead!
You can attach boosters to anything. It just costs more. -
Anonymous Coward on Sunday November 07, @12:26PM