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Turbulence in the ionosphere and global warming

  1. Jun 10, 2008 #1
    A smooth surface aborbs less sunlight than a rough one because more light is reflected.
    It takes relatively little energy to disturb a smooth surface.If the sea becomes more turbulent because of a changing wind direction or wind speed does the sea heat up more by absorbing more sunlight.And similarly if the ionosphere is made more turbulent by solar radiation does it absorb more or less energy.Does the atmosphere below the ionosphere become hotter or colder? I ask because it seems to me that the recent (recent in geological timescales) cycle of ice ages and interglacials never used to exist.Something - a unique event - caused the cycle to start.And the Earth's temperature has been rising after each glacial closer to a maximum which corresponds with the temperature just before the glacial-interglacial cycle started.
    Since chemical reactions in the atmosphere of the Earth don't take tens of thousands of years to restore an equilibrium,a long term process must be at work.And the sun has to be the prime supsect because it being a star evolves and passes through a series of unique one-off stages.Also events such as El Nino (which has occurred over thousands of years) and the Pacific Decadal Oscillation seem to be increasing in intensity but not dependent on the total global temperature for their existence.So does the current trend in global warming merely reflect some process in the Sun that is gradually returning to equilibrium after the initial perturbation at the start of the first glacial period tens of thousands of years ago.If turbulence in the ionosphere is a major factor in solar radiation absorption then the sun's output of radiation would have to vary very little - just a small extra input of some particles into the Earth's upper atmosphere to cause turbulence and a large change in the overall absorption of solar energy.
    Last edited: Jun 10, 2008
  2. jcsd
  3. Jun 11, 2008 #2
    The interglacial -glacial cycle may be caused by acoustic waves in the sun which could alternately compress and decompress hydrogen gas and thus adjust the rate of helium production and therefore the surface temperature of the sun.These acoustic waves would have to be like slow-moving standing waves (the whole waveform would translate through space simultaneously) to have a long-term effect.Particles leaving the surface of the sun might by Newton's law cause a reaction force that then sends a shock wave to the centre of the sun and back again to the surface.Over time the radius of the sun would change and so a different part of the standing acoustic wave would be compressing or decompressing hydrogen and increasing or decreasing the rate of helium production.The glacial-interglacial record cannot be explained by milankovitch cycles alone or internal factors on the Earth.
    Last edited: Jun 11, 2008
  4. Jun 11, 2008 #3
    Sound energy can become highly concentrated as is demonstrated in the phenomenon of sonoluminescence where some researchers have said that temperatures of more than 20,000K have been achieved in small - 10^-6 metre wide - bubbles.If sound energy from the surface of the sun was to similarly become concentrated at the bubble at the centre of the sun where nuclear fusion is happening, then the temperatures could get high enough to cause more fusion to occur. During an ice age the temperature on earth only changes by about 5 K which is only about 0.02 per cent change in absorbed solar energy.So the nuclear fusion rate in the sun would only have to increase slightly.
    If there isn't enough sound energy created by mass being ejected from the sun's surface then perhaps sufficient energy is generated by collapsing cavities within the sun.
    The glacial-interglacial cycle of 41000 years ( obliquity of earth's axis drives this cycle) switched for some unknown reason to 100,000 years in the last 1 million years.
    The reason is not known.It may simply be the case that when the 41000k cycle is about to cause an ice age the sun's output of radiation increases because of an increase in nuclear fusion on account of acoustic compression of the sun's core ( presumably acoustic energy can bounce around in the sun for a long time).The postulated change in behaviour of the sun in the last 1 million years could result from the collapse of a cavity (ies) in the sun's interior.
    Last edited: Jun 11, 2008
  5. Jun 11, 2008 #4
    Another possibility for the 100,000 year glacial cycle could be that the core of the sun is behaving like a Cepheid variable star in which helium becomes doubly ionised.In cepheid variables the ions on and near the stars surface regain electrons and reach a lower energy state ( usually within days).This could take a much longer time at the centre of the sun ( energy would be released ) where the pressure and temperature are higher.But why and how the sun suddenly would switch to this "internal cepheid" is hard to fathom. Perhaps it has something to do with the age of the star and the amount of helium it has produced in its lifetime.
  6. Jun 12, 2008 #5
    To explain why the glacial-interglacial periodicity is so variable perhaps we should also invoke a second periodic mechanism - a cepheid type variation in the sun in which a layer of singly ionised helium alternates with a layer of doubly ionised helium and regulates the sun's luminosity ( by only 2 per cent or so) over the millennia.The evidence for most glacial-interglacials is that Milankovitch events cannot explain the intensity of the climate fluctuations on their own so some other mechanism is required.
    Last edited: Jun 12, 2008
  7. Jun 12, 2008 #6
    Hi battery

    You are speculating a lot. But indeed many of those problems are still as unsolved as a hundred years ago.

    In cases like this, it's better to drop all conclusions and start from scratch. Scratch would be: why do we think that the isotope stages are indeed ice ages and interglacials? Obvious? But not if you see large herds of mammoths roaming the productive steppes in North Siberia around the last glacial maximum, where there is now high arctic tundra desert, unable to sustain more than an odd musk ox.
  8. Jun 12, 2008 #7
    This is a good argument.However the absence of ice in the steppes doesn't mean it wasn't colder than normal on the Earth as a whole. The distribution of energy among the ocean currents and air currents can change dramatically in one given region but the amount of energy on the globe as a whole can still be consistent with glacial-interglacial periods.
    Last edited: Jun 12, 2008
  9. Jun 13, 2008 #8
    Perhaps, but there are still a few issues. Mind that this concept is based on the affirming the consequent fallacy. The idea of glacial-interglacial periods is consistent with the ice core and oceanic cores isotopes but then again, for instance Hubberten et al show three glaciations in the late Pleistocene (Weichselian) for North Europe, fossil evidence suggesting more or less complete retreats in between, with little evidence of that in the isotope stages and the 100 ka cycle.

    Furthermore, there are several more anomalies, like oceanic reorganisations during the last transition, suggesting indeed a much bigger role for the ocean than generally assumed. But if it is the ocean, why would it be the sun too? You can't use evidence twice, unless of course you can demonstrate how the sun gets the deep ocean on the move.
  10. Jun 13, 2008 #9

    There can be atypical behaviour in one part of the world - Northern Europe - but is it statistically significant behaviour? The isotope ratios of O16 to O18 or of C14 to C12 depend on what is happening in the rest of the world too and air currents may have been bringing in air rich in O16 and C14 from other parts of the world.The complete retreats of the glaciation suggests it was warmer than normal and this would favour higher concentrations of light isotopes in the air throughout the rest of the world.The oceanic reorgnisations would have to happen often and in synchrony with just about every glacial-interglacial period because the magnitude of most glacial-interglacial climate fluctuations is larger than anyone has yet been able to explain.
    A sun with a constantly oscillating radiation output would be a more likely candidate to explain the fluctuations.Even if the sun affected the deep ocean currents it would be a remarkable coincidence if it affected them in such a way as to release CO2 from the ocean floor in a big pulse each time.
    I should also add that as the earth goes around the sun every year we don't seem to get a dramatic increase or decrease in solar radiation ( apart from the changes attributable to our changing distance from the sun ) and this shows the sun - even allowing for convection currents within its mantel is fairly uniform.Significant changes in solar radiation output are likely therefore to come from a slow, long-term, symmetrical and perhaps oscillating process - luminosity in cepheid variable stars is an oscillating and symmetrical process ( the gas envelope expands uniformly).Because gravity is so strong in the sun the expansion of a helium gas shell around the core would be tiny but could still be associated with a large amount of energy.
    Last edited: Jun 13, 2008
  11. Jun 14, 2008 #10
    Wow you cover way too many ground in that little post.

    Some things to ponder about: if for some reasons the sun fainted during the periods we call glacials, how is it possible that Mammoths, horses, aurox, etc trived on productive grassy steppes, with only moderate winterhardy plant species like the Greater Burnet (found in the stomach of the Yukagir Mammoth). Now with the sun on 'high' again there is only snow and some very slow growing tundra vegetation with freezing temperatures most of the year. What would the situation out there have to be when the sun was really low?

    Next, we take isotopes for granted all to easily, since Willi Dansgaard discovered the relationship between isotope ratios of water (dD and d18O) and temperature. But it is basically an affirming the consequent fallacy. If it rains the streets are wet but if the streets are wet, does it rain? So if the temperature is high, the isotopes are high, but if the isotopes are high, was the temperature high?

    There is also for instance the 10Be and 14C relationship, which is attributed to solar activity. An active sun with more solar rays etc also increases 14C and 10Be production in the atmosphere, which can be traced back in the geologic records. Now, during the Holocene, several 14C and 10Be spikes match closely, supporting that idea. But not during the last glacial transition at the end of the Pleistocene. Several 14C spikes but no 10Be spike between 20 and 11,500 years ago. Then there is a big 10Be spike at 26,000 years ago (Mono Lake geomagnetic excursion?) but no 14C spike.

    Also the temperature regime around the Younger Dryas proves to be a lot more complicated than the simple ice core isotope spikes suggest.

    There are more things in heaven and earth, Horatio, Than are dreamt of in your philosophy.
  12. Jun 14, 2008 #11
    You make some good points and I don't think that some sort of helium oscillator exists at the sun's heart now anyway because it would be difficult to explain why the oscillator would take so long to oscillate.

    Dealing with the points you make:
    I am not suggesting the sun would have to change its output dramatically.

    The strange behaviour of the beryllium and carbon isotopes you mention may have nothing to do with temperature but chemical environment.A 14C spike when beryllium is low could be due to beryllium being absorbed by gravel etc. preferentially in a specific chemical environment that existed at a particular time.And the same goes for the anomaly with the carbon isotope.You mention Mono Lake - this is a very specific chemical environment.
    Last edited: Jun 14, 2008
  13. Jun 14, 2008 #12
    The core of the sun is poorly understood because it is hidden from us.If the rotating core of the sun has a magnetic field and this changes with time then this magnetic field could affect the distribution of electric charges in the sun's other regions and thus the ability of light to escape from the sun to the Earth.I think it is an important observation that as the earth travels around the sun on a yearly basis we do not measure dramatic changes in solar energy reaching the Earth (that cannot be accounted for by changing distance of the Earth from the Sun).This suggests that the core is uniform and so is its magnetic field.Perhaps the strength of the core's magnetic field is what changes with time but this would require a change in temperature.To conserve angular momentum its speed of rotation could change over time if,as it uses hydrogen, it heats up and expands,then cools and heats up and expands again.A faster rotating magnetic field would exert a greater force on charged particles within the sun.
    Last edited: Jun 14, 2008
  14. Jun 14, 2008 #13
    Because it takes one million years for heat from the core to reach the sun's surface the change in glacial-interglacial frequency over the last 1 million years may have been initiated by changes in the core at least 1 million years ago.The rest of the sun may also be going through an expansion/cooling cycle in response to the heat from the core.The two processes won't be acting in synchrony (because of the million year gap) and this could generate some complexity in the climate records.If the core expands because of increased heating as hydrogen is used up, then its magnetic field will probably get weaker as the temperature drops again and less energy is available to accelerate electrons.
    The action of the magnetic field on the charges in the outer part of the sun would affect the amount of light able to get to the Earth and add further complexity to the climate records.
  15. Jun 16, 2008 #14
    Because the interglacial/glacial cycle has a frequency of 100,0000 years for the last 1 million years there have been 10 such cycles.If the cause of them is an oscillating core of the sun , alternately expanding and cooling and then contracting and heating up,
    then we would expect there to be 10 alternating bands of high and low density material in the sun because it takes one million years for heat at the sun's core to reach the sun's surface.These bands ould have a width of about 10^6- 10^7 metres. Acoustic waves in the sun of similar wavelength would be be diffracted by these bands.Perhaps there is some evidence of this in satellite and observational data where the surface of the sun has been affected.
    Although I have heard that the solar neutrino problem has been solved we can't be sure of this because half the missing neutrinos may be getting expelled from the sun at some preferred angles that do not coincide with the Earth or its orbit around the sun. There may also be a deficit of neutrinos because the core is currently larger and cooler than it can be.Also I would think that acoustic waves in the sun, of similar wavelength to the core's width, would have energy absorbed by the core (causing the core to vibrate a little ) and would thus have a weaker amplitude than waves of other wavelengths.
    Last edited: Jun 16, 2008
  16. Jun 16, 2008 #15
    Too many things here at the same time.

    1: "Mono Lake" is about a geomagnetic field collapse (excursion) 26000 years ago, first seen in sediment cores taken from Mono Lake, hence the name. The extend of this collapse is uncertain because the symptoms are not globally reproduced. However there was a 10Be spike not a 14C spike concurrent with that effect. During a magnetic field collapse the intensity of cosmic rays is supposed to increase, which would lead to more 10Be prodcution.

    2. The 100,000 years cycle. A solution to that cycle should also include the reason for the sudden emerging one million years ago and why it is not seen nowhere else in the ODP (Oceanic Drill program) sediment cores. It would also be nice if all of this could be linked to the enigmatic Mid Pleistocene http://digital-library.canterbury.ac.nz/data/collection3/etd/adt-NZCU20070227.155625/02whole.pdf [Broken].

    It's in the ocean where we see all those changes, so why can't the cause of the 100,000 years cycle be in the ocean?
    Last edited by a moderator: May 3, 2017
  17. Jun 16, 2008 #16
  18. Jun 16, 2008 #17
    The beryllium 10 may be increasing because of emission of more gamma rays by the sun and not because of magnetic field collapse on Earth.Also I 'm not sure how accurate the Beryllium data is given that Be10 is only found in trace amounts.
    The 100,000 year cycle may not be present earlier in the Oceanic Drill Program because
    volcanoes could have been emitting gas to compensate.But the volcanoes are unlikely though to have such good timing! Perhaps the core of the sun had a shorter oscillating cycle before the 100,000 year switch and in future the cycle will get longer than 100,000 years or shorter.The cause of the sudden change in frequency of oscillation could be the speeding up of the core's rotation speed -a slower moving spinning object experiences a greater force from external sources than a quicker moving one and so can be compressed more quickly.The magnetic field of the core may be interacting with the magnetic field of the rest of the sun in a periodic cycle which can slow it down or speed it up.
    The stilostomella extinction in my opinion was caused by a change in temperature of deep ocean currents.Silostomella of bigger surface area /volume ratio, lived or died preferentially.
    The ocean currents could have warmed up because of the sun (stilostomella may also have been affected by chemical changes in the sea).It is important to realise that the intensity of most glacial-interglacial fluctuations cannot be explained by internal processes on the Earth alone.The sun is always present as a possible explanation.
    Last edited by a moderator: May 3, 2017
  19. Jun 16, 2008 #18

    I don't think this is likely now, given that the sunspot cycle -also associated with magnetic changes in the sun -is only eleven years.

    If a fixed solar hot/cold cycle of 100,000 years has always existed throughout history but has been suppressed by some phenomenon on the Earth until 1 million years ago then what
    stopped the suppression.The one thing that is rarely discussed is the possibility that the plate boundaries could be removing/adding solutes and gases in the oceans,changing the solute concentration of seawater and hence the vapour pressure of gases at the sea surface.Perhaps 1 million years ago the plate boundaries removed more solutes from the sea than had ever happened before and allowed more CO2 to escape into the air heating up the atmosphere.Because so much is hidden and unexplained about what is below the Earth's crust we rarely think of the mantle as a contributing to what happens to the atmosphere.
    The ice age started 2 million years ago probably because of the higher elevation of land masses lowering temperatures.The pressure in the mantle beneath must have changed radically and this could be what promoted an increase in solute removal after convection currents in the mantle,perhaps 1 million years later,brought changes in mantle composition to the plate boundaries.
    I personally believe that El Nino and The Pacific Decadal Oscillation are caused when mid-ocean ridges and subduction zones change the solute concentration in deep ocean currents resulting in changes in gas vapour pressure at the sea surface and hence changes in air temperature and sea temperature.
    Last edited: Jun 16, 2008
  20. Jun 18, 2008 #19
    This is all somewhat speculative. We have some pretty good geologic records over the last 100 million years, considering the Maritieme Isotope Stages (MIS) -without the 100ka cycle in the first 99 million, there many more things like, paleo magnetics, fossils, etc.

    That's certainly not the same as saying that we do understand what happened the last 100 millions years. Especially when we cannot begin to explain the last 20,000 years of that. Sure, you can run suppositions along the known data, but that would require using all those data and not bringing solutes and gasses in the equation, which happens all the time.
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