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Climate Hustle

Do volcanoes emit more CO2 than humans?

What the science says...

Select a level... Basic Intermediate

Humans emit 100 times more CO2 than volcanoes.

Climate Myth...

Volcanoes emit more CO2 than humans

"Human additions of CO2 to the atmosphere must be taken into perspective.

Over the past 250 years, humans have added just one part of CO2 in 10,000 to the atmosphere. One volcanic cough can do this in a day." (Ian Plimer)

The solid Earth contains a huge quantity of carbon, far more than scientists estimate is present in the atmosphere or oceans. As an important part of the global carbon cycle, some of this carbon is slowly released from the rocks in the form of carbon dioxide, through vents at volcanoes and hot springs. Published reviews of the scientific literature by Mörner and Etiope (2002) and Kerrick (2001) report a minimum-maximum range of emission of 65 to 319 million tonnes of CO2 per year. Counter claims that volcanoes, especially submarine volcanoes, produce vastly greater amounts of CO2 than these estimates are not supported by any papers published by the scientists who study the subject. 

The burning of fossil fuels and changes in land use results in the emission into the atmosphere of approximately 30 billion tonnes of carbon dioxide per year worldwide, according to the EIA. The fossil fuels emissions numbers are about 100 times bigger than even the maximum estimated volcanic CO2 fluxes. Our understanding of volcanic discharges would have to be shown to be very mistaken before volcanic CO2 discharges could be considered anything but a bit player in contributing to the recent changes observed in the concentration of CO2 in the Earth's atmosphere.

Volcanoes can—and do—influence the global climate over time periods of a few years but this is achieved through the injection of sulfate aerosols into the high reaches of the atmosphere during the very large volcanic eruptions that occur sporadically each century. But that's another story...

Recommended further reading on CO2 and volcanoes can be found here: Terry Gerlach in Earth Magazine ; USGS

Last updated on 31 May 2014 by John Cook. View Archives

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Related Arguments

Further reading

Tamino has posted two examinations of the "volcanoes emit more CO2 than humans" argument by looking at the impact of the 1991 Pinutabo eruption on CO2 levels and the impact of past super volcanoes on the CO2 record.

The Global Volcanism Program have a list of all volcanoes with a Volcanic Explosivity Index (VEI) greater than 4 over the past 10,000 years.

Comments

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Comments 51 to 100 out of 282:

  1. Another way of putting 'it':

    That the 155 W/m2 LW 'forcing accounts for 33 K temperature difference is itself theoretical (not so much uncertain, but it is theoretical), and couldn't be observation evidence against a 0.3 K/(W/m2) no-feedback (or feedback included in 'forcing') sensitivity.
  2. "But the greatest heat transfer occurs in regular cycles at subduction zones and that is the interesting part. What besides tidal forces can cause these cyclic events?"

    But I've never seen anywhere any evidence or theorty to back up the first sentence there. The closest I've come to it was a website which seemed to be stating ENSO was caused by submarine geothermal activity, but it seemed to be (ill-informed) speculation - just guessing, really (and so I didn't bother to mention it until just now).
  3. CORRECTION:
    PARAGRAPH IN "Patrick 027 at 14:27 PM on 24 September, 2008":

    "Dissipation: heat - atoms have to move around in a phase transition; conceivably, even in a short period, some portion of the atoms near phase transitions in the mantle might be cycled through different arrangements (statistically - I wouldn't imagine the phase transition is knife-edge, or that on that timescale it could get near equilibrium (?), and there are the gradual phase transitions from or to garnet, so I wouldn't expect it's the same atoms each time around) - that might be a location where there is some relative concentration of tidal dissipation into heat energy. Not that it would be a significant source of heat. I would try comparing it to the radioactive heat generation in the mantle per unit volume if I had the time. "

    Some of the logic I used above should be correct, BUT not the part about phase transitions dissipating the forcing that drives them into heat - that was totally wrong. Atoms move around due to thermal energy - those that have enough energy (statistically some fraction will, depending on temperature) can reach some threshold and leave the energy well of their former position in the crystal lattice (or in other situations: overcome the kinetic barrier to chemical reaction or nuclear fusion, etc.) and then fall into another position - in this case, kinetic energy is converted into potential energy, and then back into kinetic energy. Lack of thermal energy simply reduces the number of atoms that are able to move around like that, and so reduces the speed at which a phase transition can occur.

    Of course, if the final energy well is shallower or deeper than the initial, then there will have been a net exchange between kinetic and potential energy, which tranlates to taking up or giving off latent heat.

    Since material properties are temperature and pressure dependent (which is of course why the thermodynamic stability of a phase is dependent on these things), there could be a net latent heating or cooling over a cycle if the phase transition in one direction and in the reverse are not occuring at the same T,p - which of course will happen if there is a time lag due to the kinetic barrier. However, the specific heat of the material will also vary, and I suspect the end result of all this is no net temperature change over time.

    Except in the case that there is a net change in the microstructure over the course of many cycles - crystal grains have to form and reform, and if the grain sizes over time shrink, then there will be an increasing number of atoms whose energy is not as it would be within the crystal lattice... (PS this might build up to a point of dynamic equilibrium, beyond which factors that tend to increase grain size over time (annealing?) would balance those tending to reduce grain size over time.

    But anyway, as interesting as it is to consider tidal cycling of phase transitions in the mantle, I expect this is a very, very, very minor effect in the scheme of things.
  4. "However, the specific heat of the material will also vary, and I suspect the end result of all this is no net temperature change over time."

    Well, now I'm not sure about that...
  5. ... I was thinking of the heat content of the material at a given temperature, and the the difference in heat capacity of two phases must be related to the latent heat of phase transformation - and it's dependence on temperature, by the requirement that whatever path is taken, taking one phase at T1,p1 and ending up at another phase at T2,p2, the same net change in heat content of the material must have occured. But that's an assigned temperature change.

    A cycle of out-of-equlibrium (time-delayed) phase transitions might concievably require a net mechanical energy input and so would produce heat...

    But see the last part of comment 53 (PS I had meant to identify that it was comment 46 which contained the paragraph I was correcting in comment 53).
  6. Because I mentioned the motion of charged particles in the Earth's magnetosphere ealier:

    (PS all the following (except stated formula) is just from visualization; so some uncertainty in some places)

    About motion (velocity v) of charged particles in magnetic field B, without other forces considered (if I'm not mistaken),

    where component of v parallel to B is vB, the component perpendicular to B is vp, all acceleration is is in direction of vector cross-product q(v x B) = q(vp x B), which is perpendicular to v, so that |v| is constant

    (q is electric charge (more generally, force F = q(E + v x B), where E is electric field (as a vector), and so acceleration is proportional to q/m, m being the mass);

    with E set to zero, let r be the radis of curvature of the trajectory projected onto the plane normal to B; so that
    |vp|^2/r
    = centrifugal acceleration
    = q/m * |vp x B|
    = q/m * |vp||B|

    r = (m/q) * |vp|^2 / (|vp||B|)

    r = (m/q) * |vp|/|B|

    1.
    Constant field B:

    helix on a cylindrical surface (field lines parallel to surface), would would appear as a straight line on the surface if unrolled. |vB| and |vp| are constant. Radius of cylinder proportional to |vp|.

    2.
    Change in magnitude of B in direction perpendicular to B (aside from 1., the easiest to visualize):

    The trajectory, or it's projection onto a plane normal to B, has tighter curvature in regions of higher B. This leads to a net displacement over the course of one revolution (to where v has the same direction). Their is thus a net drift in the direction that v has in the weaker B side of the field. Looking with B vectors directed toward you, positive charges revolve clockwise (turn to the right), and the net drift is directed with the stronger B field to the right. Negative charges: opposite. Smaller q/m ratio (as with proton compared to electron): larger radius of curvature, which itself means greater net displacement over each revolution, but also means greater variation in |B| over the range of each revolution, which means even greater net displacement over each revolution.

    3.
    Variation in field strength along B - convergence or divergence of field lines (also means, over distance perpendicular to B, change in direction of B in the same dimension):

    helix on a conical surface (or something like that) - vB shrinks to zero and then reverses as larger B is approached, so the trajectory is 'repelled' by larger B values. This means |vp| must rise approaching larger B. In the other direction, as B shrinks, vp also approaches shrinks as v becomes more parallel to B.

    4.
    Over distance perpendicular to B, change in direction of B, but in direction perpendicular to both B and to the direction along which the variation is detected:

    Suppose there is one field line, aligned with the z-axis, where x and y = 0, about which the particle is revolving in the same dimension.

    Case A: variation only in the x direction, all field lines parallel to y-z planes, where in the positive x axis, field lines have increasing slope dy/dz.

    In this case, when v is in the positive x direction, B is changing so that ... well, to make a long story short, I think the result is a helix on a cylinder, but the cylinder (whose axis is the z axis) is flattened in the x direction (?).

    Case B: braided (twisted) field lines. In this case, if one starts with vB in the positive z direction, then if the field lines curve around each other going in the postive z direction in the same direction as vp, then vp is less than otherwise, vB is more than otherwise, and the result is a helix on a cylinder (??) with a larger radius than otherwise for the same velocity in the x-y plane. If B is twisted in the opposite direction, the cylinder would have a smaller radius for the same velocity in the x-y plane.

    5. Change in direction of B along B (curved field lines)

    This one is trickier to visualize... Locally one may consider approximately constant field strength and field line curvature; but when the radius of curvature is small enough or the range of positions large enough, constant curvature of field lines requires change in field strength along field lines, while constant field strenght requires increasing field line curvature toward a center of curvature, unless field direction is also changing as in case 4. above.

    ---

    There are someone conically shaped regions above each polar region; With B directed from the south pole to the north pole, if one visualizes the Earth with north pole pointing up, then within the ~ conic regions, B is downward, while outside the ~ conic regions, B is upward; B should increase in field strength toward the Earth. Thus, protons should have a net westward and electrons a net eastward drift especially outside of polar regions due to effect 2., many are 'repelled' from the poles due to effect 3. Effect 5 will also come into play (not sure of effect); 4, or at least 4B, is not a feature of a basic dipole field but I suppose it might occur due to disturbances or to the motions of charged particles themselves (and also within the core?).
  7. Patrick
    Sorry, I have read your argument a dozen times trying to see your logic but I simply can't. I am afraid it's too abstract for me.
  8. "I have read your argument a dozen times"

    Wow! Thanks for the effort!

    I suppose it would have been helpful if I had written a summary.

    TIDES ON EARTH: Outside of oceanic effects (and maybe a few glaciers at sea level), too weak to expect a significant effect on:

    1. mantle convection and the overall rate of plate motions (which can't change fast anyway).

    2. earthquakes and volcanic activity - at least in the longer term trends (as opposed to variations over cycles of 1/2 day, day, 1/2 month, month, etc.), if not even in those shorter term cycles.

    3. the Geodynamo and outer core motion

    4. the atmosphere, ionosphere (including E-region dynamo, in the base of the thermosphere), and magnetosphere (except in the magnetotail at those times of the month when the moon actually would get near or intersect it, although even then, on further reading it seems the magnetic forces on charged particles with the kinds of energies involved would overwhelm gravitational effects - and also, outside of the monthly and ~18-year cycles, what effect could that have, and even then, what would the significance of that be to Earth?)

    And where the tides have a significant effect, how would that effect relate to climate changes over a ~100 year period (as opposed to a ~ 20 year period or especially a 1/2-month (spring to neap to spring again)period)?

    TIDES CENTERED ON SUN (due to planets): far too weak to expect significant effect on:

    1. solar convection or solar dynamo, and hence, 11-year sunspot cycle, other related phenomena including TSI variations
    2. solar wind and interplanetary magnetic field (except, for effects on Earth, perhaps when Earth get's near the wake of Venus or Mercury, - **although most of that effect wouldn't actually be from the gravity of Mercury or Venus - and what effect could it be?) - this is especially considering the case considering the much much larger variations that do occur in solar wind density and velocity...

    TIDES ON SUN VS 'SOLAR JERK', FAIRBRIDGE CYCLE:

    I had thought that if the there was a correlation of solar TSI or solar wind and magnetic field to the solar jerk, it would be because they would both be correlated to the tides on the sun, which might have an effect on solar TSI, wind, and magnetic field (though an insigificant effect for our purposes, from my reasoning). The solar jerk is just the changing free-fall of the sun so it is hard to see how that would affect solar activity (as I explained elsewhere).

    However, it is interesting that while both such tides and 'jerk' depend greatly on Jupiter, the jerk depends also on the other gas giants due to their mass and distance, and the contribution of the 4 inner planets is tiny in comparison, whereas the three most important planets after Jupiter for the tides on the Sun are Venus, Earth, and Mercury.

    ----

    ... Further reading on magnetosphere, solar wind...:
    (PS I have only browsed many of the following, with one noted exception):

    http://en.wikipedia.org/wiki/Magnetosphere
    http://en.wikipedia.org/wiki/Magnetosphere_particle_motion
    http://en.wikipedia.org/wiki/Guiding_center

    but of course one must be careful with wikipedia (their article on tides suggests the human menstrual period could be an evolutionary artifact of distant sea-dwelling ancestors' adaptations to tidal cycles, when in fact this doesn't seem likely at all, particularly considering the menstrual cycle periods of our closer relatives - it is just a coincidence) - on the other hand, it is possible to figure out whether or not the math and physics work out as such.

    But also:

    http://www-ssc.igpp.ucla.edu/ssc/tutorial/magnetosphere.html
    (which I have read completely)

    http://farside.ph.utexas.edu/teaching/plasma/lectures/lectures.html

    http://www-istp.gsfc.nasa.gov/Education/Intro.html

    -----

    On a possible connection of oceanic tides to climate:
    http://www.pnas.org/content/94/16/8321.full

    I think there was a related article to the above, which focussed on a correlation of shorter term variability to oceanic tidal forcing. I haven't read through these closely enough to see just how much variability in tidal forcing there is relative to the tidal forcing itself - the largest I do expect is the spring-neap variation, but there are other variations... but I expect they are smaller especially in the long term variations - so I am arguing that oceanic tidal variations are significant in climate variations on the multidecadal to century to millenial or beyond timescale, but it is interesting to consider. I don't think the authors would or could argue that this could account for the warming of the last few decades...
  9. ... aside from that:

    1.
    Unclear that recent changes in Earth's magnetic field are anything unusual over the same time period in which recent climate changes are unusual. (**PS I'd be curious to see if the previous changes in magnetic field, either in strength of dipole or actual reversals, correspond in any significant way with the paleoclimatic record, or anything else. One would think it could affect some species (birds, turtles?), though there is no evidence of enhanced extinction rates during reversals, as far as I know).

    2.
    While new discoveries are made about submarine volcanic activity, there hasn't been a discovery of temporal changes in this, either significantly correlated to ENSO or other climate variability, or to global warming, and the same for volcanic activity in general - (except perhaps for the going into and out of a ~quiet period with respect to explosive volcanism above water, which wouldn't explain global warming of the last 100 years but apparently has influence (But not control) over ENSO).

    3.
    As far as I know, the torques on Earth that contribute to two of the Milankovitch cycles do not result in true polar wander - the rotational axis changes orientation but the whole body of the Earth shifts with it, so the North pole remains in the Arctic over such cycles.

    4.
    anthropogenic greenhouse forcing may be a little less than 2 % of the total greenhouse 'forcing' (including water vapor and clouds), but the small size of that proportion may not mean what some may think; a total forcing (greenhouse + albedo) that in terms of globally averaged radiative forcing would be somewhere between 3 % and 5 % of the same total greenhouse 'forcing' accounts for the global warming between the last ice age and preindustrial climate.
  10. Patrick
    Much better, thank you.
    Re: 1
    Magnetic orientation for birds etc. may simply be lines of force rather than a true polarity orientation. A reversal likely has little effect but shift does to some extent, I would not expect extinctions however.
    Re: 2
    I disagree here. But as with any hypothesis there is room for doubt. This is under study so I am content to wait on the outcome.
    Re: 3
    The pole remains in the Arctic yes but the amount of direct sunlight changes with the angle of attack.
    Re: 4
    I am uncertain of this, which is why I am here.
  11. Quietman,

    "Re: 3
    The pole remains in the Arctic yes but the amount of direct sunlight changes with the angle of attack."

    Yes - this much is a widely understood aspect of Milankovitch cycles.

    "Re: 2
    I disagree here. But as with any hypothesis there is room for doubt. This is under study so I am content to wait on the outcome."

    If you could find articles which specify changes in time (of geologic activity, aside from major eruptions above water, of course) correlated with any climate changes on the scale of years to millenia, I'd very much like to see it.

    Clarification - as I recall now, there was some speculation about possible temporal changes in geothermal heating of ice at two locations - somewhere in northern Greenland, and somewhere in West Antarctica. In each case it appeared to be only speculation, though. And I don't think those could have enough regional or global significance to account for much of recent climate changes. (With all the volcanos in the world, certainly a few could just happen to change just as anthropogenic emissions are becoming a big player, but it would seem quite a coincidence if enough volcanos in the right areas happened to change activity to have regional and global climatic significance at this time and yet not for some longer period of time prior to now (as inferred by paleoclimatic records and ice sheet conditions, etc.))
  12. Patrick
    You still assume AGW is a big player and I do not. See the sensitivity thread.
  13. ... will post response at: http://www.skepticalscience.com/climate-sensitivity.htm
  14. Satellite Data Reveals Extreme Summer Snowmelt In Northern Greenland
    ScienceDaily (Oct. 10, 2008) — The northern part of the Greenland ice sheet experienced extreme snowmelt during the summer of 2008, with large portions of the area subject to record melting days, according to Dr. Marco Tedesco, Assistant Professor of Earth & Atmospheric Sciences at The City College of New York (CCNY), and colleagues.
  15. Interesting article.

    Is meltwater perculating up from below to heat the ice? Geothermal heating would melt the bottom first; even with infinite thermal conductivity, the melting point of ice is lower at higher pressure. Depending on the thickness of the ice at that location, it might take considerable time for a change in heating to propogate upward.

    I think a majority is from AGW.
  16. Patrick
    In the Greenland thread I have added an abstract that is applicable in answer.
  17. PS
    I posted a link in comment 267 in Arctic sea ice melt - natural or man-made? which is also applicable as a response.
  18. correction: comment 257 (not 267).
  19. Patrick
    In other words it would appear that the arctic is subject to some very unusual weather causing much of the problem for the past half century. The question now becomes, what caused the change in pattern. My tectonic argument based on "the solar jerk" offers an explanation for this change while the IPCC argument does not.
  20. "My tectonic argument based on "the solar jerk" offers an explanation for this change while the IPCC argument does not."

    1.
    But the 'IPCC argument' (also the argument of many others) may very well explain it... (more on that later)

    2.
    How 'on earth' is the tectonic argument linked to the solar jerk?

    a. is it that tides, which may be correlated with solar jerk, are acting on either the geodynamo or tectonics or volcanism (all of which I strongly doubt (tidal variations weak, variations over relavent time periods weaker still), outside butterfly effects that take time and are not discernable as predictable links among individual causes and effects)?

    or

    b. that solar activity affects Earth's magnetic field, which of course does happen, BUT - I am very doubtful (with the same caveats as in a.) of any significant role of solar jerk or tides on the sun in changing solar activity, or of any significant link between changes in the outer core geodynamo and tectonics on the relavent timescales (mantle is very slow and reacts very slowly to changes in outer core convection), or of much effect, at least on the relavent timescales, that solar and space 'weather/climate' perturbations on Earth's magnetosphere and E-region dynamo could have on motions and magnetic field in the core, considering how much much much more massive the core is and how much more intense the field is in the core (yes, there is a lot of momentum and energy per unit mass in the magnetosphere, but still I expect much more total momentum and kinetic energy within the outer core), and also that, at least as far as I know, the strongest (relative?) perturbations of the magnetic field due to space weather occur at greater distances, where the field is even weaker still.

    ------------

    Back to 1:

    Greenland article abstract (referenced in comment 66): the effect of meltwater is to lubricate the base of the glacier causing faster flow; sudden changes can occur as water flows. Effect may be limited. Nowhere does it state that the meltwater has increased due to geothermal heating - not that that's not a possibility but - without actual eruptions or sudden magma movement up through cracks, changes in geothermal heating must be slow - could it account for a significant change over only decades? How much heat would be necessary to account for the amount of water melting? Wouldn't there be some indication of volcanic activity (from a pattern of earthquakes (discernable from icequakes or quakes due to changing ice mass and isostatic adjustments??); sulfur concentration in meltwater outflow????)...

    I think this phenomenon of basal lubrication of the ice is not limited to the area where a underlying hotspot is thought to be.

    ---

    Arctic sea ice loss article:

    "Rising Arctic Storm Activity Sways Sea Ice, Climate
    ScienceDaily (Oct. 6, 2008)"
    http://www.sciencedaily.com/releases/2008/10/081006180815.htm

    What I got from that is:

    There was an expectation from climate theory ("derived from model results") that a warmer climate would lead to a northward shift in storm tracks and increased storminess in the arctic.

    This expectation has been verified from the observations.

    Observations also indicated that the changing circulation patterns have affected, through wind, the Arctic Ocean circulation, via movement of sea ice.

    Transport of sea ice:

    "The team found that the pace of sea ice movement along the Arctic Ocean's Transpolar Drift Stream from Siberia to the Atlantic Ocean accelerated in both summer and winter during the 55-year period."

    "Progressively stronger storms over the Transpolar Drift Stream forced sea ice to drift increasingly faster in a matter of hours after the onset of storms."

    (I'm not sure how similar this flow pattern is to the flow of ice associated with the 2007 circulation anomaly that pushed warmer air into Siberia - in that case, however, the atmospheric circulation pattern was not unprecedented, but resulted in record minimum ice because it was acting on top of an overall warmer atmosphere and thinner sea ice, etc. - because of ongoing global warming. There will be highs and lows; on top of an upward trends the highs and lows with both be higher, except potentially for the trend's effect on the shorter term variability itself.)

    Ocean mixing:

    "The moving sea ice forces the ocean to move which sets off significantly more mixing of the upper layers of the ocean than would occur without the "push" from the ice. The increased mixing of the ocean layer forces a greater degree of ocean convection, and instability that offers negative feedback to climate warming."

    That last part is potentially great! - that more CO2 might go into the oceans - BUT it is also potentially worrisome - will it speed up ice loss? Will it make it harder for new ice to form each winter as the fresher meltwater is mixed into the saltier water? - and of course because of the ice albedo feedback?
  21. Patrick
    But in fact the thinned crust is the northern end of Greenland (in the articles linked in this thread) and surrounding Arctic ocean and that is exactly where the largest glacial melt is AND IT IS FROM THE BOTTOM.
  22. Ice albedo will remain until all the ice is gone. Soot in the top layers lower the albedo so fresh ice will have a higher albedo if we control the output of soot.
  23. They do not say if it is AGW either. In fact they do not say why at all (in that article). But top down melting would not produce the same results, nor would it be restricted to only northern Greenland where the crust is thin (they DO describe it as a "hot spot" in the other article and suggest that vulcanism is a "contributer" in an earlier article. I do think they are at last on track.
  24. Patrick
    Keep in mind that while you and I can speak openly for or against the AGW concept. there are others who need to be politically correct or they will lose their jobs or grant money and therefore skirt the issue. Then there are those, like one poster at this site, that are environmental fanatics who look upon AGW as a bible thumper looks to the word of God. Hopefully we will get to the truth behind all this regardless of their attempts to "enlighten" us "deniers" (that is their demonization of skeptics vocabulary, not mine).
  25. Patrick
    To save time and server space, I ask you to read the comments in "Arctic sea ice melt - natural or man-made?"
    as that is where I presented my hypothesis en todo. It technically should have been placed here, but I got angry and a little carried away when I got double teamed. But there were some good points made by all in my opinion.
  26. SO how/why would global warming alter storm tracks?

    I know a good amount about circulation patterns in the atmosphere and yet there is A LOT I don't know, but what I know, have been able to deduce, or otherwise have gotten the impression of, is:

    Remember hot air tends to rise and cold air tends to sink; this happens because of the pressure variations caused by the variations in air density. For a column of warmer air, the pressure is either lower than otherwise below it, higher than otherwise above it, or some combination of the two (at least for the hydrostatic approximation). The coriolis effect, on the large scale more than on smaller scales, tends to impede the simple 'thermally direct' circulation just described by causing wind to blow nearly parallel to isobars (or lines of constant geopotential on isobaric surfaces).

    The atmosphere is generally at least somewhat stable to dry vertical motion; this means that dry adiabatic cooling and warming are such that, the rising/sinking induced by a warm/cold anomaly tends to reduce the anomaly.

    Midlatitude storms do get some energy from latent heating (as with tropical storms), but unlike tropical cyclones, midlatitude storms get much of their energy from the available potential energy of a background horizontal thermal gradient. This thermal gradient supports a vertical wind shear (hence the jet streams).

    In the hydrostatic approximation (which is a good approximation in the asence of significant vertical acceleration, which is generally the case of larger scale motions), horizontal divergence/convergence must occur along with vertical compression/stretching (in pressure coordinates), respectively, which implies variations in vertical velocity with height (in pressure coordinates).

    In order to conserve angular momentum, which is the case in the absence of friction (and friction is generally weaker than the pressure gradient and coriolis forces in the midlatitudes), horizontal convergence/divergence must occur with an increase/decrease in the magnitude of vorticity - vorticity is a measure of the air's 'spin'. It's important to realize that this pertains to absolute vorticity, which is the sum of planetary vorticity (which is proportional the coriolis effect itself) and relative vorticity. Relative vorticity can be cyclonic or anticyclonic, such as in cyclones or anticyclones, respectively (although horizontal shear also contributes to vorticity). But the absolute vorticity is never anticyclonic except near the equator. Thus, vertical stretching, such as below rising motion or above sinking motion, tends to cause cyclonic motion, which requires a low pressure area to be balanced; and the opposite tends to cause anticyclonic motion, etc.

    *A1*.(Notice that if continued to extremes, relative anticyclonic vorticity can be at most equal and opposite to planetary vorticity, whereas there isn't such an upper bound to cyclonic vorticity, aside from the limits of the vertical stretching itself). Related to that, centrifugal forces allow for, for a given wind speed, greater pressure gradient around a low center than around a high center. (?? Another potential reason for assymetry is that divergence is ultimately limited by space but convergence is not ??, and also, a divergent air mass is growing larger in area whereas a converging air mass is shrinking ??, although air diverging from one point must ultimately also be converging toward another. ??)

    PS the measure of absolute angular momentum that is conserved during any inviscid (frictionless) adiabatic motion is isentropic potential vorticity. With constant static stability, potential vorticity (PV) is higher where absolute vorticity is higher; with constant absolute vorticity, PV is higher where static stability is greater.

    AND THEN:

    Disturbances in a region of vertical shear that are tilted into the shear - that is, if the vertical shear is westerly (eastward) with increasing height, the tilt of the pressure perturbations is westward with height - and moving at an intermediate speed between the extremes that occur higher and lower in the troposphere - can grow because the configuration allows for ...(Baroclinic instability) ... okay, well that's too complicated to go into right now, but to summarize:

    I think these disturbances can grow faster when the vertical static stability is lower - that is, when the laspe rate is higher. At the same time, higher lapse rates favor shorter-wavelength systems for maximum growth rates. Development is enhanced by greater horizontal temperature gradients and associated vertical wind shear.

    Although these disturbances could start out sufficiently small that linearized equations may describe them initially, they may eventually grow to the point that nonlinearities become important, and nonlinearities may be important to start with depending...

    so surface low pressure systems develop east of developing upper level troughs (assuming overall westerly average winds) and west of developing upper level ridges, and high pressure systems at the surface would develop east of upper level ridges and west of upper level troughs. There are also fronts. warm air heads poleward east of the low and rises, cold air west of the low heads equatorward and sinks. The configuration is such that (generally**) the low pressure system itself will tend to build poleward, eventually with the center attached to the warm air mass at the surface by an occluded front that underlies warmer air aloft. The high pressure will build equatorward. The pressure systems eventually lose some of their tilt, and thus their ability to strengthen vanishes. At this point, due to the sorting out of surface highs and lows, there is an overall westerly flow at lower levels in between them. If the north-south transport of heat by these systems was fast enough relative to the gradients in radiative and latent heating, vertical shear will have been reduced within the heart of the storm track, though it and the temperature gradient may actually have increased on the edges of the storm track as the warm fronts push into the cold air and the cold fronts push into the warm air. The overall effect of the disturbances may generally be to concentrate westerly momentum at upper levels into the storm track but also to transfer westerly momentum from upper levels to lower levels. Eddy potential energy and kinetic energy have both been produced from some of the available potential energy of the original horizontal thermal gradient, but also some has been produced from eddy-correlated latent heating and perhaps radiative heating (??) patterns, although radiative heating in the absence of cloud or humidity variations will tend to reduce eddy energy; some eddy kinetic energy is transferred back into the kinetic energy of an average across disturbances, and some of this kinetic energy is actually converted back into available potential energy by a thermally indirect circulation. I think this is because as the lows and highs 'sort out' and the warm air and cold air masses move past each other, the rising motion is shifted to the cold side of the storm track and the sinking motion is shifted to the warm side of the storm track. One way of quantifying this is with something called the EP flux, which is related to a potential vorticity flux. Factors, such as the horizontal shear of the average state, may affect the 'sorting' out process and the life cycles of the disturbances...

    Energy generated in the troposphere in these disturbances is spent in the lower stratosphere by lifting colder air and 'pulling' warmer air down. I'm not sure whether this energy is lost (radiatively ?) or is transferred back into the troposphere (to the extent the stratosphere acts like a trampoline). The thermal pattern produced in the lower stratosphere acts to reduce the strength of the disturbances at yet higher levels, thus they do not penetrate much above the lower stratosphere (though larger scale features do).

    Larger scale features (longer wavelength troughs and ridges) exist which do not grow in strength from baroclinic instability (although different waves can interact through nonlinearities), but rather propogate westward throw the air at all levels in the troposphere. These larger scale features may be excited by the wind's flow over topography and by some variations in temperature, and also by propogation around the globe of barotropic Rossby waves that are produced by convection over tropical sea-surface temperture anomalies, etc.

    These features affect the distribution/patterns of storm track activity.

    -------

    So with global warming (in general, not generally specific to cause):

    The expected pattern in the Northern hemisphere (which would, I think, be expected in both hemispheres in the longest-term equilibrium states) is enhanced warming in the mid-to-upper troposphere in low-latitudes and, especially in the colder seasons, in the lower troposphere and surface at higher latitudes. This is because:

    At high latitudes, there is a strong albedo feedback, associated with reduced seasonal snow where there is some sunlight in winter, and summer sea-ice loss nearer the pole, which has a warming effect in winter by absorbing summer sun and taking longer to freeze while giving off more heat in the process during winter. The atmosphere is generally more stable at higher latitudes, especially in colder months, so the additional heat at lower levels may not be transfered to the rest of the troposphere by convection so much as it otherwise would. At low latitudes, there is a negative feedback over the ocean and moist surfaces (so long as they remain moist) as evaporation is faster at higher temperatures; the upper level heating is from the corresponding condensation of moisture. Some of that heat can be transported out of cloudy areas by circulation, of course. The changing lapse rate can be related to the temperature dependence of the moist adiabat.

    Thus the equator-to-pole temperature gradient, and thus the vertical wind shear at some point in between, is reduced at lower levels (except perhaps in summer or around that time of year) and increased at upper levels.

    These trends won't be distributed at both levels in the same way and won't be distributed evenly at all latitudes and longitudes, but starting with an even distribution assumption:

    1.
    Due to the temperature gradient changes in the lower troposphere, one would expect reduced midlatitude storm track activity overall (except perhaps in or around summer, when it is not as great to start with, although mesoscale circulation (thunderstorms, squall lines, MCCs, etc.) do produce severe weather and intense precipitation events at that time, and severe thunderstorms are aided by vertical wind shear as well as moisture and moisture contrasts **). It might also perhaps allow for greater poleward-penetration of conditions that allow tropical cyclone development.

    HOWEVER:

    2.
    Due to the temperature gradient trend at upper levels, one might expect greater midlatitude storm track activity (although this may be more sensitive to lower level thermal gradients and wind shear than upper level thermal gradients and wind shear), and also perhaps limit the regions that allow tropical cyclone development.

    3.
    Interesting feedbacks: greater thermal gradients tend to enhance storm track activity which itself mixes the air on large scales which ultimately reduces the thermal gradient, so changes in storm track activity can be a negative feedback to changes in thermal gradients.

    If the reduced thermal gradient at lower levels reduces storm track activity, heat transport may be reduced at all levels, allowing the thermal gradient to increase at upper levels.

    If the increased thermal gradient at upper levels increases storm track activity, heat transport may be increased at all levels, reducing the thermal gradient at lower levels.

    Although of course the heat transport for a given circulation pattern will be greatest where the thermal gradient is greatest.

    (note that general circulation models, although not perfectly, will incorporate these effects, so the expected pattern of temperature change described before wouldn't necessarily be different because of storm track activity feedbacks).

    4.
    Greater overall moisture in the atmosphere will also enhance storm track activity by adding to eddy available potential energy (and through that, to kinetic energy) by greater latent heating.

    *A2*. Since this affects essentially only precipitating systems, it's effect is asymmetrical between cyclones and anticyclones (as might also be the case with eddy-correlated cloud feedbacks). However, the more intense latent heating tends to be concentrated on smaller scales, so I'm not to what degrees it would enhance the synoptic-scale system, enhance mesoscale features, or change the character of the low pressure system, perhaps by making it more intense but more compact with more intense precipitation over a smaller area (?). Would there be more subtropical storms?

    PS more moisture overall in the air may also imply greater moisture transport across a given moisture gradient, and if temperature were rising equally everwhere, the moisture concentration gradients would increase - except of course, the temperature is not rising evenly everywhere. But temperature increases could increase the effect on regional and global circulation patterns of any given SST (Sea Surface Temperature) anomaly, such as that associated with ENSO (which itself may increase due to the delayed warming of upwelling cold water). Mesoscale humidity contrasts (drylines) are important in many severe thunderstorms, including tornadic storms.

    5.
    IF the lapse rate were to remain constant, the greater latent heating would reduce the static stability effect on cyclones, which might then develop more rapidly, especially those with smaller horizontal sizes, but not on anticyclones. The greater latent heating itself may reduce the lapse rate, perhaps reducing but not eliminating the changes in cyclone development, while also slowing the development of anticyclones, especially smaller anticyclones. (If larger anticyclones are preferred ??, would that lead to larger airmasses, with reduced thermal gradients across some regions but enhanced thermal gradients around the edges of anticyclones, perhaps if wind is delivering air from longer distances without getting side-tracked, and hence over shorter times ??).

    6.
    Note also that the overall expected temperature change pattern is such that vertical static stability is increasing at lower latitudes, but is decreasing at higher latitudes. This could concievably account in part for a tendency to shift the storm track activity poleward Notice this may mean a poleward expansion of subtropical dry regions into the midlatitudes as well as an increase in precipitation at higher latitudes on top of what might be expected from higher humidity alone.

    7.
    Interesting feedbacks. When the overall thermal gradient is increased from a low value, the circulation due to synoptic scale eddies (includes storm track extratropical cyclones) increases. This includes vertical motion. Hence, there is greater vertical heat transport, which tends to increase vertical static stability, which slows the development of these baroclinic disturbances (baroclinic eddies; a.k.a. midlatitude storms and anticyclones), especially those of shorter wavelengths. In actual 'dishpan' experiments (a spinning pan filled with fluid and differentially heated and cooled), when the thermal gradient is very low, there is a Hadley cell; when it is increased, baroclinic disturbances form, when it is increased further, the wavelengths of the disturbances increase (as I recall), up to a point, until the wavelength of unstable disturbances is too large to fit into the pan, and so the Hadley cell resumes. However, there isn't an actual short wave cutoff in the atmosphere, although some simplified mathematical descriptions produce one - but it is true that the most unstable wavelength increases with increasing vertical stability.

    In the actual atmosphere one can also have small scale overturning as in cumulus clouds and thunderstorms. If the large scale overturning of either the Hadley cells or the extratropical circulations or both were reduced, one might expect that the vertical stability would decrease until and causing the smaller scale overturning to pick up the slack.

    8.

    The coriolis effect is of course also very important. The coriolis effect varies with latitude, increasing away from zero at the equator.

    The variation of the coriolis effect over a north-south distance is called beta, and beta effects tend to cause disturbances, especially larger horizontal wavelength disturbances, to propogate westward relatively to the air flow; this produces a long-wave cutoff where some wavelengths are too large to develope by baroclinic instability. If the wavelengh, beta, and windspeed are right, a wave may remain nearly stationary - such quasistationary planetary waves can be excited by topography and variations in temperature, as mentioned before.

    I think beta also reduces the mechanism by which baroclinic disturbances grow through baroclinic instability, by contributing to convergence where there is divergence and vice-versa - at upper levels, anyway (maybe the opposite at lower levels, however - do the effects cancel?). Perhaps not as much if the overall flow is somewhat northward or southward over a whole wavelength of ridges and troughs...? - actually, this might turn out to be mathematically equivalent to some fraction of the other beta effect in the prior paragraph.

    Beta decreases away from the equator, to zero at the poles.

    So if the storm tracks move, the coriolis and beta effects will vary as applied to the storm track activity.

    Also, the tropopause is expected to rise. But the tropopause slopes downward toward higher latitudes. So it is unclear what happens to tropopause height at a moving storm track. A higher tropopause could affect storm track activity - for example, for a given wind shear, the total variation in wind would be greater across the troposphere. Perhaps the effect of topography would be slightly reduced at the upper levels ???? - And a given level of divergence in the air through the troposphere could increase the surface pressure fall if occuring through a greater thickness of air ????. And the relationship to the stratospheric circulations... the energy generated in the troposphere relative to that expendended in the stratosphere, that relationship would change.... More generally, deeper convection = more intense precipitation, and higher cloud tops increase the cloud's contribution to the greenhouse effect.

    9.
    So the storm track activity changes. This changes the average wind patterns. That affects the way quasistationary planetary waves develope from topography and temperature variations, which again affects the wind and thus the storm tracks. Changes in SST affects how the SST anomalies (which themselves could change in frequency/intensity/location/etc.)affect all of the above (including but not limited to ENSO, PNA?). Etc. One way storm track activity can change is by changing the motion of storms - if storms move more slowly or are farther apart, for example, one could have greater risks of floods or droughts, and the opposite for the reverse; a greater portion of precipitation coming in intense events may lead to greater runoff; the frequency and locations of blocking events could change; blocking anticyclones are associated with dry spells and heat waves; I suppose they might lead to the opposite somewhere else since cyclones may be rerouted around such anticyclones...Etc. Changing winds, wind shear, and static stability, affect the distribution of gravity waves and whether and how they propogate vertically, which would affect transfer of momentum from the troposphere to the mesosphere; the vertical propogation of planetary waves into the stratosphere could also be affected and that is associated within 'Sudden Stratospheric Warmings', and stratospheric circulation can then affect the troposphere. Related: would NAM, SAM, NAO, and QBO be affectd? Etc.

    I might be wrong about some things - especially towards the end, some of that was speculation (where I was unsure I tried to indicate as much). But at least I hope to have given you a sense of how global warming can alter weather patterns.
  27. *A3*. If anticyclones are larger horizontally they will then tend to propogate westward relative to the wind faster than cyclones (beta effect), so cyclones will tend to move eastward with the overall wind faster than anticyclones, or in order to move at the same speed, anticyclones would have to be closer to a westerly jet ... etc... AND as anticyclones sort out equatorward of stormtracks, they would experience higher beta and so their eastward movement would be slower for that reason as well - unless there is another effect that counteracts this.

    PS to be clear,

    My understanding is that:

    In baroclinic instability, eddies grow by taking available potential energy (APE) from the average state (averaged along a storm track across a full eddy wavelength, for example, or a full zonal average across all longitudes for the overall midlatitude storm track activity) and thus creating eddy APE, essentially by moving the cold air and warm air into each other (creating a wave pattern in the isotherms or isentropes along a horizontal or near horizontal surface) - at the same time, this disrupts geostrophy so that a thermally direct circulation occurs, with winds moving from high to low pressure horizontally, with warmer air rising and colder air sinking. This converts some of that eddy APE to eddy kinetic energy (KE), which enables the eddy to distort the isotherms even more, and thus continue to grow - for small disturbances, growth can initially be exponential.

    Two things: when warm air is pushed as a protrusion into colder air, the resulting pressure perturbation is initially unbalanced by the coriolis effect and so the warmer air rises - warmer air that was initially surrounded (horizontally) by air of a more similar temperature is now surrounded by colder air, and so rises, just as actually adding heat to a region of air tends to make it rise. However, depending on the geometry, some of the surrounding colder air may also sink as it is now next to warmer air. The effect may not be as strong as in the warmer air since the colder air is not surrounded by the warmer air, however (mathematically, it depends on the laplacian of the temperature advection). But if new warm air continues to flow from the main warm air mass into the cold air, the cold air will eventually adjust and stop sinking while the warmer air is still coming into a new situation and will still rise. IF the temperature gradient is initially constant from warmer to colder, than, for the sake of clarity, assuming an initially north-south temperature gradient (east-west isotherms), a wave pattern of flow that is limited from north to south will pull isotherms apart in the warmer side while pushing them together in the colder side, or vice versa, and where isotherms are pulled apart, a thermally indirect circulation will develop, converting KE to APE. However, where isotherms are pushed together, the thermal gradient can get higher and higher (until some ageostrophic effects associated with frontal zones get strong), whereas the pulling apart of isotherms can at most reduce the gradient to zero (PS I haven't actually calculated this but I would assume this means the thermally direct circulation eventually dominates while the themally indirect circulation dies out). Also, if the initial thermal gradient is concentrated near or along the storm track, there might not be so much pulling apart of isotherms even initially to cause a balancing thermally indirect circulation.

    Anyway, an east west cross section of an idealized series of such growing eddies may show alternating high and low pressure centers tilting westward with height, regions of rising and sinking motion, strongest in midlevels (air won't rise into space or go down into the surface) which also tilt westward with height but not as much, and regions of warmer and colder air that tilt eastward with height. The air flows through these features from west to east higher up and from east to west closer to the surface. Because the temperature and vertical motion patterns don't tilt the same way with height, there can be some pockets of thermally indirect circulation, but overall it is mostly thermally direct. What is really interesting about these kinds of systems - you might well wonder, how can they grow - how can the pressure systems get stronger - when the thermally-direct motions that create the kinetic energy associated with the wind requires that air is on average flowing into low pressures and out of high pressures? The answer: by temperature advection (transport of air)(not actually by heating, although that will occur but is not part of this explanation), the air in between the highs and lows is warmed or cooled because of the north-south flows. But the east-west flows through the system act on this pattern, so that the resulting temperature field doesn't tilt as much as the pressure field and actually tilts the other way. The vertical motion reduces the growth of the temperature pattern by adiabatic cooling and warming of the warmer and colder air, respectively, and this effect is greatest at midlevels (or tends to be, but will also be greater at levels with higher static stability). Near the surface, warmer air is closer to lower pressure; at higher levels it is closer to the higher pressure (opposite for colder air). Pressure drops faster with height through colder denser air than through warmer air, so the low pressure tilts with height over the colder air to its west, and the high pressure tilts with height over the warmer air to its west. The temperature field explains the way pressure changes with height, but what explains the actual pressure field at any one level, such as the surface? There has to be some total divergence through the whole column of air above the surface low pressure to result in lowering the pressure (assuming flat topography - pressure systems can also be produced by motion over slopes). There has to be convergence into the low pressure on average in order to increase kinetic energy. But with height, the high pressure tilts part of the way over to above the surface low, so divergence from that high pressure can lower the pressure at the surface, while convergence at the surface increases the high pressure aloft. What about angular momentum? Air is vertically stretched beneath warm rising air at midlevels, while also being transported by relative westward motion (relative to this whole pattern) into the low pressure at low levels levels; so cyclonic relative vorticity is created that can nearly balance the pressure - but not quite, or else their could not be net convergence into the low (actually, there could also be some effect of centrifugal force, which affects high and low pressures asymmetrically - although centrifugal force depends on the trajectories, whereas vorticity is determined from streamlines**), and at upper levels, air is vertically stretched above sinking motion while being transported westward into the low pressure at that level. And so on for the growth of anticyclonic vorticity in the high pressure areas. The whole pattern can grow exponentially, up to a point. When the flow pattern of the disturbances is stronger, the warmer air is not just moved east west toward low and high pressure centers, but continues to move north and south more significantly due to the wind of the disturbances. Thus warm air flows northward from south of the low (did I mention I'm describing a Northern Hemisphere version) east of the low and westward relative to the low, into the low as the low moves east, but also continues northward and goes north of the low. Rising motion and the surface low itself will follow. Another way of looking at it is that the flow of air above the low is not just westward but northwestward, between a trough and a ridge at mid-to-upper levels... and generally, features at one level in the atmosphere tend to propogate with the wind at another level because the wind at that level must adjust to the feature, and the feature must adjust to that adjustment...

    So in the 'sorting out' process where the highs and lows at the surface tend to end up on different sides of the jet stream and temperature contrast associated with the storm track, when the motions are averaged along the length of the storm track, it may appear that colder air is rising and warmer air is sinking, but this may largely be (?) the result of warmer air rising while surrounded by colder air, and colder air sinking that is surrounded by warmer air. Mathematically this can be worked out as a thermally direct eddy circulation which is producing more kinetic energy than is being taken back by the weaker thermally indirect averge motion. At some point, though, I could imagine that even while the warmer air and colder air are still warmer and colder than their immediate surroundings, they may have cooled and warmed enough, respectively, that they are no longer warmer and colder than each other, respectively; at that point the average thermally indirect motion would be stronger than the eddy thermally direct motion, I think, so that in total kinetic energy is being converted to APE. Of course, the eddy motion itself might start converting some KE to APE at some point during the decay stage (?)- perhaps frictional dissipation may force cold air up in the lower levels of the low pressure system, for example - which would strengthen the low pressure aloft but reduce it at the surface (although the convergence at the surface would reduce it at all levels, but at higher levels the disruption of geostrophy would induce flow to counteract whatever pressure tendency there is - not entirely unlike the way electric currents respond to a changing magnetic field).

    I did see your most recent comments and I'll get back to you about that.
  28. Re #66, 67, 71, 73 etc.


    The notion of significant volcanic/tectonic contribution to polar ice melting simply isn't supported by the evidence, Quietman, and most of the articles that you link to don't support that notion either.

    Much of the analysis of enhanced melt/glacial runoff that is contributing to nett mass loss in Greenland is from regions far from the Gakkel ridge in the far NE region N of Greenland where some tectonic activity has been found.

    It's already been pointed out by Patrick that the surface melt highlighted by Tedesco et al in their EOS article is incompatible with the effects of undersea tectonic activity. This is highlighted by Tedesco himself who indicates that the snow melt is associated with surface/air maximum temperatures 3 oC above average. Clearly that cannot be the result of undersea volcanos.

    The situation is similar to the article you linked to on the Greenland thread (your link in post #66 above). It's easy to see that this article (citation below) discusses surface melt on the Western region of the Greenland ice sheet, and specifically concerns surface melt in the ablation zone 1500-2000 metres high up in the ice sheet. This enhanced surface melt cannot be the result of undersea volcanic activity 1000 miles away.

    and so on. The papers you link to are inconsistent with the effects of undersea tectonic activity.

    An additional problem relates to the question whether this activity (undersea tectonics) has increased in a manner that is consistent with the timescale of enhanced warming. You linked to a paper in your post #13 above which you consider to be some sort of support for a contribution from tectonic activity to the very marked enhanced warming of the last century and especially the last 30-0dd years.

    However this paper (Loyd et al, 2007; citation below) simply doesn't support that notion. The specific point of the Loyd paper that you link to is that the release of thermal heat from the earth's tectonic activity has steadily decreased over the last many million years. Now it may be that there is some evidence for enhanced tectonic activity, but the paper you linked to certainly doesn't provie any. If anything it provides completely contrary evidence to your hypothesis.



    R. S. W. van de Wal (2008) “Large and Rapid Melt-Induced Velocity Changes in the Ablation Zone of the Greenland Ice Sheet” Science 321, 111 – 113.

    S. J. Loyd et al (2007) "Time variability in Cenozoic reconstructions of mantle heat flow: Plate tectonic cycles and implications for Earth's thermal evolution" Proc. Natl. Acad. Sci. USA 104, 14266-14271.
  29. Re #74:

    The suggestion that scientists "skirt the issue" because of worries about funding/grant money or political correctness is ludicrous and isn't a scientific argument. It's a conspiracy theory.

    The essential element of science and one that allows us to address difficult and complex issues relating to real world phenomena is that it is evidence-based.

    All discoveries/interpretations that are supported by the evidence have a place in science and are likely to appear in the peer-reviewed scientific literature. If interpretations are not supported by real world evidence they are very unlikely to appear in the literature or to be taken very seriously, especially be scientists who are pretty skeptical people. And of course we should all be skeptical of assertions/arguments without an evidence-base. Of course we're free to discuss unsupported hypotheses to our hearts content, but unless evidence accrues to support these, one should remain skeptical.

    Castigating individuals as "environmental fanatics who look upon AGW as a bible thumper looks to the word of God", seems more like an insult that a scientific argument! I haven't posted here that long and haven't come across any people that seem to have unreasonable concern for the environment. However surely one should address their argument/evidence rather than insult them.

    In science it's all about the evidence Quietman.
  30. In science it's all about the evidence Quietman.
    Yes but first you have to examine it instead of dismissing anything you don't like off hand or because you don't like the author or what he/she says. You can't skip through and ignore key words and phrases the way you like to and you can't assume that a paper is fact, peer reviewed or not. It is an argument, ie. a hypothesis.
  31. Patrick
    That was directed at chris. You put forward a good argument regardless of what points I disagree with and do so using logic rather than a peer review bible. Keep it up, you do a good analysis.
  32. PS
    Re: "SO how/why would global warming alter storm tracks?"
    I thought that you made a good explanation or at least a good argument for that in the Bertha thread.
  33. Patrick

    "Sandwiched between Earth's crust and molten outer core, the vast mantle accounts for 83 percent of the planet's volume. It is filled with solid rock but, heated by the core and by its own radioactive decay, it circulates like a pot of impenetrable soup. That circulation is the driving force behind the surface motion of tectonic plates, which builds mountains and causes earthquakes."
    Ref:
    Geophysicists Propose A New Model Of Earth's Mantle ScienceDaily (Mar. 19, 1999) - Earth's mantle, a region as scientifically remote as outer space and the object of the most heated debate in geophysics, gets a remodeling this Friday by researchers at UC Davis and MIT

    PS I would remind you that the capacity for "sudden" changes was covered in my post 36. But I found a good link for the article at ScienceDaily (June 20, 2008) — Surprisingly Rapid Changes In Earth’s Core Discovered " The movements in the liquid part of the Earth’s core are changing surprisingly quickly, and this affects the Earth’s magnetic field, according to new research from DTU Space." ... “What is so surprising is that rapid, almost sudden, changes take place in the Earth’s magnetic field. This suggests that similar sudden changes take place in the movement of the liquid metal deep inside the Earth which is the reason for the Earth’s magnetic field,” Nils Olsen explains.
    Ref: The Abstract in Nature.

    Viewed with the article of Tectonics acting as the Earths thermostat it can be seen how the thermostat can become suddenly reset for periods of time.
  34. Re #80/#81

    That makes no sense at all. The reason I questioned your choice of links is that I downloaded and read each paper thoroughly (rather than just the press releases). So I certainly "examined it"! In fact I thought the papers were excellent (papers have to be pretty good to be accepted in Proc Natl Acad Sci or Science and so on...). I thought the authors were fine and I was perfectly happy with what they said (male and female alike!). So your odd accusations don't apply and one wonders why you don't address the critique of your interpretations, rather than reply with inappropriate insults. There's clearly valid questions of whether (a) undersea volcanic/tectonic activity has increased in a manner that could have a causal relationship with the rather large global-scale warming of the last 100 years, especially the last 30; (b) whether tectonic activity has made a significant contribution to widescale polar ice melt. A skeptic should like to see some real world evidence.

    The point is that the papers that you cited don't support your notion. In other words you can't use as evidence of undersea tectonic contributions to Greenland melt, a paper that describes high level ice sheet surface melt at the ablation zone 1500-2000 metres in altitude in Western Greenland. That's not the result of undersea tectonic activity. It's a consequence of enhanced atmospheric warmth.

    Likewise one cannot use as evidence of enhanced tectonic contributions to global warming a paper whose essential analysis is to describe the continual steady decrease in thermal heat from plate boundaries due to their consolidation from previously smaller fragments over millions of years. And it's obvious that every paper about tectonics does not willy-nilly constitute an "argument" about tectonic contributions to global warming! We all know that plate tectonics is a fundamental element of the earth system. The question with respect to largescale global warming is whether this activity has increased recently.

    So there's nothing wrong with the papers - you've just chosen to cite papers that provide data and evidence that contradicts the notion that you are pursuing.

    And one should be careful in relying on press releases for scientific information.
  35. "But in fact the thinned crust is the northern end of Greenland (in the articles linked in this thread) and surrounding Arctic ocean and that is exactly where the largest glacial melt is AND IT IS FROM THE BOTTOM. "

    I only read the abstract. It sounds like chris may have read more. Is he incorrect about the article?

    "But top down melting would not produce the same results"

    It depends on what exactly the results are.

    Meltwater could come from the surface, flowing down into the glacier through moulins - this source would explain the seasonality of any meltwater-induced lubrication of the glacier.

    (Of course, however the ice is melted or induced to flow, the resulting thinning would lower the ice surface and cause warming of the ice surface that way.)

    --

    "Ice albedo will remain until all the ice is gone. Soot in the top layers lower the albedo so fresh ice will have a higher albedo if we control the output of soot."

    Dark aerosols are/have contributed to arctic warming and melting in that way; that is true. tropospheric ozone has also contributed to Arctic warming and melting. So has CO2, CH4, etc.

    However, the highest albedo is from fresh snow. Old snow and ice tends to have a lower albedo. When snow melts and refrezes or otherwise changes to form larger particles, the reflectivity is reduced - light may penetrate deeper before being reflected, giving it greater chance to be absorbed. Aerosols (and rocks), natural or anthropogenic, will be concentrated as the ice volume is reduced. Sea ice will become more transparent and thus darker when it gets thin enough to see the water beneath.

    The loss of sea ice will likely have a warming effect (in the winter, at least) on the region, not just where the ice was lost.

    --

    "suggest that vulcanism is a "contributer" in an earlier article"

    Potentially so but only in a few locations, whereas the ice mass loss and general warming are far far far more widespread and general.

    "They do not say if it is AGW either."

    I think at least some of the articles you referenced did say that, not about some of the specific locations but about much of the other warming.

    ____________________________________
    Entering danger zone?

    "Keep in mind that while you and I can speak openly for or against the AGW concept. there are others who need to be politically correct or they will lose their jobs or grant money and therefore skirt the issue."

    Scientists and politicians and everyone else are only human. However, if a scientist does work that has errors, and especially if it is a matter of interest to people, I expect some other scientist would want to capitalize on the opportunity to point out those errors. Can scientists be friends with each other? Yes, but that doesn't prevent them from pointing out each other's errors - especially if they don't take it personally. There may be actual examples to back up that point but I'll leave that to others.

    What about money and prestige? If there were no 'climate crisis', then there would be less money available to study AGW and climate in general, right? Well, I hardly think there's a Higg's particle crisis (that we know of :) ), and yet we've got a Large Hadron Collider now. Still, though, the argument is plausable. Then again, if there were more controversy than there would need to be more work done to resolve it, so...

    Still, though, whereever the bulk of the money and attention are going, there could be some scientists out there who would like to make a big name for themselves by successfully overturning the conventional wisdom of the day. If they are not able to do so, then there might be a reason why. And unless scientists are actually making up the data, the data is what it is, the potential error in that data and all, the theory (logic) is what it is, and any scientist, or student, with sufficient education can ask, does this make sense?

    There are people with an interest in overturning the current accepted science of global warming. Some of them have lots and lots and lots of money. Yet, rather than having funded real science on the matter (at least any that would successfully accomplish their goals), they instead lobby the government while launching silly propaganda campaigns about how CO2 'is life' (or that any effort to reduce CO2 emissions will harm the poor (often arguments ironically made by people who would rather not have the government do the poor any special favors, I think), or that free market capitalism will solve everything and any government involvement works against innovation - when in fact a carbon tax or some equivalent, etc, could help spur innovation and may be justified by (market) economic principles) ... Meanwhile, my impression is that, if anything, the IPCC summary for policymakers is watered down in favor of anti-alarmism, rather than hyped in the other direction.

    "Then there are those, like one poster at this site, that are environmental fanatics who look upon AGW as a bible thumper looks to the word of God."

    I can't help but wonder if this is the result of misunderstanding (not that I would pretend to know how your conversations with others have gone - I don't know). Not that it can't happen - many people don't understand science, regardless of what they have come to believe or accept as true (although the people who do understand science are more likely to accept or lean towards the accepted science or at least one or more promising contenders). But sometimes people who do know stuff just get tired and impatient from explaining and explaining and explaining and explaining and explaining and explaining and explaining and explaining and explaining again, especially when so many turn a deaf ear towards it or come back with accusations of communism, or just keep making the same arguments over and over and over and over and over and over and over and over and over and over and over and over and over and over and over and over and over, no matter how well it's been refuted to them (and maybe in some cases, being caught telling other people something totally false about what you told them - this has happened to me).

    Then what may happen is that people misread each other, assuming that the other guy is a member of the group of ignorant jerks s/he's become accustomed to dealing with. It may happen in particular when a new face advances an argument that the other person has seen before, perhaps from an actual 'denier/contrarian'. Or to save time, a person might refer to the 'scientific consensus', from which the other person may unfairly conclude that the other is just arguing 'from authority', rather than understanding the significance of such a consensus (ie sure, we can't be 100% sure about much, but there comes a time when we've got to make a decision - what do we put in our science textbooks? What do base public policy on? While there are loose ends still being worked out, relativity and quantum mechanics are scientific consensus. Many details have not been found, but the general picture of biological evolution by natural selection and some other things is scientific consensus. That the Earth is ~ 4.5 billion years old ... etc. PS Relativity didn't overturn Newtonian mechanics entirely (we still use the later for many things), and aside from that, if the argument is made that Einstein successfully overturned a consensus, 1. does that mean we could expect that Einstein will also be shown to be wrong someday, and 2. for every Einstein, how many had an idea that didn't pan out?) Although it is unfair, it is sometimes understandable why a person may make an assumption about someone's attitude to reality.

    There is also the time constraint - if a person smells 'silly' in an argument, they may decide (rationally) to not bother with it, hence, dismissing it.

    Certainly if I didn't have the time I couldn't have been discussing/arguing with you about the merits of various possibilities. I myself am quite satisfied that 'it' (you know what I mean) is mainly AGW. There are many arguments I won't look into further, because I judge them ahead of time to be wild-goose chases that will lead nowhere - I can do that with some confidence because of the arguments I have looked into that turned out to be just that, empty fluff. Occasionally I will look into such an argument though, just to debunk it - but of course, if I can't debunk it, that will tell me something, won't it? (Either that it may be possible, or that it is beyond my knowledge). Another aspect to this - perhaps an application of Occam's razor - there are so many things that are known, that lead to an expectation of significant CO2 causing significant warming - that Arrhenius (sp?) predicted as much long before CO2 emissions ever rose to such a level - the understanding of how radiation transfer actually opperates has been refined since then, as have the radiative properties of gases, etc, - but not in a way to discredit the basic idea, rather just to refine the theory. Then there is paleoclimatology, the computer models, the observations so far, etc. - they all inform each other, of course, but even taken independently they point in the same general direction. Given all that, some of these alternative explanations - it seems like throwing in extra Rube Goldberg devices and lasers to explain how the toaster works, after you've already seen the nichrome wires glowing red... Now, I may still want to learn about some things for other reasons - I don't think the tidal-driven ocean mixing will account for much of recent changes but I find it interesting as a phenomenon all by itself, for example.

    "Hopefully we will get to the truth behind all this regardless of their attempts to "enlighten" us "deniers" (that is their demonization of skeptics vocabulary, not mine)."

    This is messy. Take out the 'offensive words', and what is left behind essentially describes, in my mind, what I hoped to accomplish - enlighten you.

    Why wouldn't I call you a denier or contrarian? Well, because you've been polite and seem willing to listen, you haven't accused me of being a communist, a dumb parrot, or having malice or indifference towards innocent people, and you aren't trying to cast yourself as a climatologist or a scientist in some related field.

    I was actually afraid I've 'led you on' when you implied someone else might consider me a denier, so now - in jest - I will say that some of those I have argued with would call you a communist.

    As for those words - denier, contrarian - there are people out there to whom I think they would justifiably apply. For example, dare I say Fred Singer and Richard Lindzen. I don't say this just because they say things I disagree with - I say it because they say things that can't be backed up, they make arguments that are shot full of holes, and especially in Fred Singer's case, I am tempted to doubt whether he himself could possibly buy into his own arguments - or else, I think he must be horribly confused and sloppy - yet, perhaps some of his sleight-of-hand reasoning is too clever for that explanation? Other people - whether they knowlingly lie or just want to believe in those things that help them politically - Rush Limbaugh, Michael Crichton, Ann Coulter, James Inhoffe, James Dobson, CEI, etc... and even Jon Stossel and Glenn Beck, - well, ... they don't identify themselves as scientists, but in some cases they are quite biased in their work, and in some cases there furosity ...

    Some would say 'denier' is offensive because it may have been inspired by the use of the word next to 'Holocaust'. I can see that, however, I can also see that it is a word, like red, and certainly no one thinks cherries are communist. Does a person 'deny' in an irrational or dishonest way?

    Your response to chris:

    "Yes but first you have to examine it instead of dismissing anything you don't like off hand or because you don't like the author or what he/she says. You can't skip through and ignore key words and phrases the way you like to and you can't assume that a paper is fact, peer reviewed or not. It is an argument, ie. a hypothesis."

    Actually, I think chris may have been saying somewhat the same thing to you. Aside from that, of course one shouldn't assume a paper, even having passed peer review, reaches the correct conclusions. But there are so many many papers ... the balance of evidence tilts clearly toward significant AGW. That there are uncertainties in feedbacks - this applies to any climate forcing, so AGW still 'has a leg up on' various alternatives (in the sense of contenders to being the major forcing of relevant changes), and the 'burden of proof' doesn't fall all the way back to showing CO2, et. al., as big players, just because of feedback uncertainties.

    In particular with 'dismissing offhand' - see somewhere above...
  36. "To save time and server space, I ask you to read the comments in "Arctic sea ice melt - natural or man-made?""

    ... will do, eventually...

    --------

    a few loose ends:

    quasistationary planetary waves - they don't tilt much with height - at least not relative to their wavelengh.

    Systems can/could also grow through barotropic instability, which is an instability caused by larger horizontal wind shear (such as on the sides of a jet stream). I don't know as much about that.
  37. Patrick (and chris)
    The papers (all papers, peer reviewed or otherwise) present an argument. That state their observations, methods used (so you can duplicate the test) and references to avoid restating prior arguments. The argument is presented largely in the "conclusions".
    The papers are all worth reading but it must be remembered that the paper IS AN ARGUMENT, attempting to persuade others to see the authors viewpoint.

    Accepting the authors conslusions is not mandatory. Peer review indicates that at least one other person in the same field of research agrees, it does not make it fact. If you read the papers carefully, in particular the methods and results you can often come to a totally different conclusion using a wider bas of information.

    All of the articles cited are related but the authors have not connected the dots. Ignore their conclusions, connect the dots and draw your own conclusions. THAT is what science is all about.
  38. Patrick
    Re: My response to chris.
    It is exactly what he/she? has accused me of on several occasions because I often do not accept an authors conclusions, especially Hansens.
  39. Re: "Dark aerosols are/have contributed to arctic warming and melting in that way; that is true. tropospheric ozone has also contributed to Arctic warming and melting. So has CO2, CH4, etc.

    However, the highest albedo is from fresh snow. Old snow and ice tends to have a lower albedo."

    Agreed.
  40. Re: "Meltwater could come from the surface, flowing down into the glacier through moulins - this source would explain the seasonality of any meltwater-induced lubrication of the glacier.

    (Of course, however the ice is melted or induced to flow, the resulting thinning would lower the ice surface and cause warming of the ice surface that way.)"

    Agreed.
  41. Re: "Potentially so but only in a few locations, whereas the ice mass loss and general warming are far far far more widespread and general."

    Of those known or recognized at this point in time. All of these articles are findings after the IPCC had decided the cause was AGW.

    Re: "I think at least some of the articles you referenced did say that, not about some of the specific locations but about much of the other warming."

    Yes some cite AGW but without making it an argument (ie. it is assumed from the start). They did not look at the issue without the background assumption that it could only be AGW. Look at the facts, not the assumptions.
  42. Re: Your comments on plausibility.
    Yes the senate has even looked into the matter. If the scientist has a position like Spencer he can speak out, it's only reputation at stake. If the scientist is junior he can be fired or asked to resign. It has in fact happened. Polotical correctness is a disease of society that has been with us since the commie hunt back in the 1950s. That is why I said to read carefully. When a scientist skirts the issue it means that he/she does not agree but will not say so.
  43. Excuse the spelling, my attention is somewhat divided today with a sick grandson.
  44. PS
    I suggest that you read this BBC November 2007 article as it does explain the skeptic attitude on this issue.
  45. The link in 94 did not work. I think I put a slash after stm so heres a copy and paste version:

    http://news.bbc.co.uk/2/hi/science/nature/7081331.stm
  46. - started reading comments in "Arctic sea ice melt - natural or man-made?" - up to 119 so far... will return later...
  47. - now up to 158. Interesting. Not necessarily in a good way... :)?

    (PS there has not been an overall warming trend in the last five million years - if anything an overall cooling trend (PS NOT claiming it is a constant linear trend) - superimposed on which are glacial-interglacial fluctuations.)
  48. - now up to 170...

    will comment more later but a brief note...

    Do the math. Do the math. Do the math. Do the math. Do the math. Do the math.
  49. Re Quietman 186 (Arctic sea ice melt...):

    Many different people at different times may use any given word. People change. It's not even the same people around today as back then. In today's world, the worst treatment of returning soldiers and their families of which I am aware is by a far-right-wing reverend from - Kansas? - who goes around protesting at funerals, and by the government itself, but of course none of this is pertinent to the subject at hand.

    I was once told in high school by an aquaintance not to say 'pasta' because it's a 'yuppie word'. I was a bit puzzled by her concern on the matter - sure it's from a foreign language and may sound 'fancy' (if you're not used to it), but ... (doesn't my using it make it not so much of a yuppie word anymore?)
  50. Echoing Philippe 190:

    Your complaints about abuse of peer review - this really doesn't prove anything regarding AGW but it may be worthwhile to note that one line of attack by creationists/ID proponents is to complaign about how their side is 'shut out' by the scientific establishment.

    ----

    I can see why you would have gotten upset by the tone of your opponents; however, I can see why your opponents overall could have gotten very frustrated with you and why they would have labelled you a contrarian/denier. Also, your references to bibles and fundamentalists and evolution, and suggesting that a person should think for him/herself, were offensive because they imply things about your opponents which I don't think were generally true (certainly not anymore than they would apply to yourself - no offense.).

    More on that later...

    --

    I can see why you (Quietman) and chris were having a hard time discussing the conclusions/interpretations of the paper(s) which used observed responses to solar forcing to figure out a climate sensitivity, which would then apply to CO2 forcing. What would have been helpful would have been for you to explicitly state one or more of the following (whichever applies to your thoughts):

    1. the efficacy of the forcings could be different (** more on that later)

    2. the solar forcing may extend beyond TSI (**although I would point out the authors apparently went on to find evidence for TSI being most/all of the solar (or solar-cycle-correlated??) forcing - I am only infering this from a quoted portion in the comments).

    3. solar forcing may be correlated with some other forcing.

    4. CO2 forcing is significantly overestimated (which is highly unlikely, I think - refer back to our earlier discussions).

    Any of these might have yielded some interesting conversation?

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