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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."
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.
Real Daleks don't climb stairs - they level the building.
We think of sunspots as following a fixed, 11-year cycle, but this may only be one part of the story.
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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Sunspots cool the suns surface though, so no.
There are two kinds of fool One says 'This is old therefore good' Another says 'This is new therefore better'- Dean Ing
"Mars has increased at the same rate as Earth for the last three or four years."
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 meta-analysis of data. While meta analysis has it's purpose, it can be filled with artifacts.
The problem points to the fact that we have released millions of years of carbon in a short 100 years.
The Kruger Dunning explains most post on
And in the last 10 years that's started to reverse.
(This time with a working link.)
Program Intellivision!
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.
As I understand a recent theory:
- Sunspots are associated with increased solar wind and coronal mass ejections,
- This improves the magnetic/plasma shielding of the earth from cosmic rays,
- Which reduces the nucleation of water droplets,
- Which reduces cloud cover,
- Which reduces reflection of sunlight,
and this reflection of sunlight totally swamps the minor change in the solar radiant output.
When the sun goes through a prolonged period of no sunspots the result is enough of an increase in reflection of sunlight to significantly drop the Earth's temperature.
If you compare the graph of sunspot numbers linked from the great-great-great-grandparent post to the wikipedia article on the "Little Ice Age" you'll see that the sunspots-went-away period from about 1650 to 1700 corresponds to the first - and drastically deepest - temperature drop. MAJOR global cooling - the temperature crash at the end of the medieval warm period which we've just recovered from.
Seems to me an "All Quiet Alert" is appropriate. This could be the start of some significant global cooling.
And that could be a problem. According to the orbit-based climate forcing models the peak of the last interglacial corresponded to the start of agriculture, and temperature should have begun a gradual but accelerating descent into the next ice age, which should have been moderately steep by now. Instead it pretty much leveled out (ignoring "minor" bumps like the two I just named and the recent upslope). If fossil-fuel greenhouse gasses are indeed holding back a downhill slide we could be in pretty sad shape in about four more centuries, when the fossil carbon runs out. And once that snow persists into summer it does a darned good job of reflecting sunlight, too.
Meanwhile, if we're going into a cold period and at the same time are cutting our carbon emissions in order to "stave off global warming" - with a resulting drastic hit on the economy - we could generate the scenario Niven and Pournelle described in _Angels Down_.
Bummer!
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Well, if we keep going, we can get it up more than a few degrees c. And 15 c would probably suffice to kill us all (a small fraction might be able to make it by moving north, but the infrastructure isn't there, and the fires would probably end civilization, leaving us vulnerable to all the other issues).
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
A little less scary if you will.In any case, during reversal the magnetic field does not go away, it only gets weaker and develops several more magnetic poles, at unpredictable locations.