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Comment on Groups and herds: implications for the IPCC by As We Are Wont | Skeptical Swedish Scientists
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Comment on Open thread: Thanksgiving edition by Tonyb
Ak
There is a fourth problem and that is environmental degradadation. In the uk many of thE proposed wind farms will be at sea but clearly visible from the shore and in some instances in world famous yachting areas such as this one in the Solent just off the south coast of England. There are numerous objections to it but the one that occurred to me- stealing wind from yachts and the land does- not seem to have been thought of
Tonyb
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Comment on Open thread: Thanksgiving edition by Jim D
Ragnaar, what we have now is not strictly a boundary-value problem either because we have a transient climate. That is, the forcing is changing rapidly and the earth system is trying to keep up. This kind of climate is sensitive to how the oceans and sea ice are modeled, for example, because they can go through transitions. This could explain part of the model divergence. A true boundary problem keeps the forcing steady and looks at the asymptotic climate. For example, from that we look look at the difference in the steady climate for a doubled CO2 as a guideline of where the climate is headed.
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Comment on Open thread: Thanksgiving edition by Ragnaar
“Their key discovery is that the ice-sheets that repeatedly formed on the Canadian Shield and extended further south than Chicago had such a huge mass that they changed the shape of the land surface beneath them so much it had an effect on climate as a whole. The reason for this is that glacial loading forces the lithosphere down by displacing the more ductile asthenosphere sideways. But when melting begins rebound of the rock surface lags a long time behind the shrinking ice volume – well displayed today in Britain and Scandinavia by continued rise of the land to form raised beaches. In the case of the North American ice sheet, what had become an enormous ice bulge at glacial maxima developed into a huge basin up to 1 km deep as the ice began to melt. Simply by virtue of its low elevation this sub-continental basin would have warmed up more and more rapidly as the ice-surface fell because of this ‘isostatic’ lag.” http://earth-pages.co.uk/2013/08/23/new-approach-to-the-milankovitch-mystery/
Make ice and more ice until the whole shooting match collapses. I wonder if this is how Hudson Bay formed?
h/t Science of Doom
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Comment on Open thread: Thanksgiving edition by kim
Gotta Little League Louisville Slugger out.
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Comment on Open thread: Thanksgiving edition by Jim D
oz4caster, the meteor impacts and volcanoes you mention would be blips of less than a millennium, or even a century, that would not show up on such a graph. What is needed is a lasting change to the atmospheric CO2 level, which is what these volcanic periods did, because they took deeply buried carbon and put it back into the atmosphere and ocean. That is the only way to get a lasting effect: to restore deeply buried carbon to the atmosphere (as in volcanoes or fossil fuels) or to rebury it as in weathering and natural biosphere sequestration. The exchange between deep and surface carbon is a major factor in explaining the climate of the last half billion years, and that has mostly been driven by plate tectonics, until now.
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Comment on Open thread: Thanksgiving edition by R. Gates
“Open threads are a free for all. well, in some universe they are.”
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Content should be open (within bounds of obscenity rules) but the presentation of that content should always be polite. There simply should be a zero tolerance for name calling of any sort.
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Comment on Open thread: Thanksgiving edition by AK
@Tonyb…
There are numerous objections to it but the one that occurred to me- stealing wind from yachts and the land does- not seem to have been thought of
Well, I’m not sure how many yachtsmen would really mind that much, it would just add to the challenge. Especially in a race, where, AFAIK, they’re allowed to steal wind from one another. Using a wind turbine as part of the race (starting line, finish line, or turning point) would probably just add to the fun when it casts a wind shadow.
Still, putting the turbines much higher, or using buoyant stratospheric CSP seems like a practical alternative (heh!).
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Comment on Open thread: Thanksgiving edition by oz4caster
@JimD
I did notice a sudden sharp drop of about 3C on the temperature graph at about 35 million years that presumably corresponds to the major meteor impacts around that time, but it was not annotated. The temperature decline that began about 50 mya halted during the very active volcanic period from 35 to 15 mya and then resumed a fairly steady decline into our current ice age. The beginning of the current ice age around 3 to 4 mya appears to coincide with the closing of the oceanic gap between North and South America by the formation of the Isthmus of Panama. Probably more than just a coincidence, and if it was causative that suggests the importance of oceanic circulations as at least a factor in driving the increasing amplitude and duration of the glacial cycles in our present ice age.
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Comment on Open thread: Thanksgiving edition by Jim D
oz4caster, I think the drop at 35 million years ago was due to the albedo effect of the first glaciation of Antarctica. The glaciation of Greenland a few million years ago preceded the descent into the Ice Ages, by providing another cooling stage, also with Arctic sea ice expanding around then. These glaciations have global temperature effects comparable with the more recent series of Ice Age glaciations.
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Comment on Open thread: Thanksgiving edition by Rob Ellison
This is just repeated from above – in relation to a comment that has since predictably disappeared.
http://judithcurry.com/2014/11/27/open-thread-thanksgiving-edition/#comment-651409
I am hardly likely to refer to myself as asshat ellison.
The comment was by springer. I have one name and it was always known – no matter what the literary game at the time was that went over springer’s head. And was used for opportunistic sniping by him and specific others. Just as it is yet again. The overwhelming tedium of this lowest common denominator free for all is the reason for so little range of inputs – and such poor quality.
You have no solution for this problem it seems Judy – and to delete my comment in an open thread pointing out the obvious yet again is frankly pathetic.
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Comment on Open thread: Thanksgiving edition by Asshat Ellison
Then again Asshat Ellison does have a ring to it.
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Comment on Gravito-thermal discussion thread by phi
Clivebest,
“There is an equal and opposite radiative flux throughout a 100% CO2 atmosphere without any gravity.”
Why is that? There is only one IR flux, it goes from the warm source (the surface) to the cold source (space).
“There can be no temperature gradient because there can be no lapse rate”
The temperature gradient is related to heat flux, not to gravity.
“Convection is meaningless.”
There is no convection and thus the heating effect of CO2 is even more important.
“Exactly the same number of 15 micron photons are absorbed at the bottom of the atmosphere as will be emitted from the top of the atmosphere to space.”
1. You must not limit to the center frequency.
2. The photon model is not suitable for thermodynamic reasoning.
3. The 15 micron frequency is practically saturated in your example, there is virtually no thermal effect on that wavelength throughout the thickness of the atmosphere. By cons, 15 microns emits very efficiently into space at the top.
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Comment on Gravito-thermal discussion thread by Joe Born
“The effect disappears, when the system is allowed to interact with the rest of the world. Any measurement performed on the system introduces so much interaction that nothing can be observed even in principle.”
I’ve never contended that the effect would be great enough to measure. But it will take more than Dr, Pirilä’s mere assertion for me to accept that the (admittedly immeasurable) effect that according to Velasco et al. does prevail will disappear suddenly when some interaction, however slight, is permitted. While it is true that the absolute isolation on which the microcanonical ensemble is based is not encountered in real life, neither is it true that the infinite-heat-capacity heat bath on which the canonical ensemble is based encountered in real life. Therefore, the exactly zero kinetic-energy gradient isn’t either. In any event we’re talking about ideal cases, not what we see in the world around us.
Consider two identical initially isolating containers of the same-molecular-weight ideal monatomic gas. The containers extend infinitely high in a uniform gravitational field. One of them has twice as much gas as the other. Velasco et al. says that the first should have a lower, but non-zero, kinetic-energy gradient than the second.
Now couple the two containers thermally, say at two different altitudes, without allowing the amounts of gas in either container to change. Will the interaction–which, notice, now permits a variation in each gas column’s total energy and therefore makes its possible microstates no longer constitute a microcanonical ensemble–cause either gas column’s kinetic-energy gradient suddenly to drop to zero?
Dr, Pirilä never seems to give me a straight answer to this. I say the answer is no, and I say that Roman, White, and Velasco demonstrate that it’s no. I don’t see how Dr, Pirilä’s quote above is correct if Roman et al. are right.
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Comment on Gravito-thermal discussion thread by Kristian
Pierre-Normand, December 1, 2014 at 12:23 pm:
<em>"The emission power from a surface only is a function of its temperature and emissivity. You can’t reduce it through allowing the surface to conduct heat away (or though latent heat release). If it’s allowed to conduct heat away, then it will just lose heat at an even higher rate. If this weren’t the case, one would think it would have been observed in the laboratory already."</em>
It should be a pretty obvious fact, almost to the point of being intuitive, that a body of water struck with the first round of a solar SW flux and thus heated to depth by it, will <em>not</em> be able to also <em>shed</em> this particular amount of energy within a similar period of time by radiating (LWIR) back out from its surface. Why? Because the energy coming in as SW is absorbed across the three dimensions of the volume of water, but the energy going back <em>out</em> as LW is only emitted from the two-dimensional surface.
The SW flux is after all not instantly able to warm the body of water up to the point where its surface temperature correlates to a LW emission flux equal to the originally absorbed SW one.
In a hypothetical, <strong>purely radiative setting</strong>, this would pose no problem. The system would simply move towards a steady state (dynamic equilibrium), by incoming (SW) energy gradually accumulating inside the volume, until the point where the surface temperature <em>did</em> finally reach exactly that level. At this point, the incoming and outgoing radiative fluxes would match and there would be no more warming.
(This is how normal, real-world objects warm, after all, by energy gradually accumulating inside them (internal energy, U, growing), fast at first, then progressively slower up to the point of balance between heat (Q) IN and heat OUT. Then the increase in U, and in T, stops.)
On our planet, however, there's an atmosphere on top of the solar-heated body of water, and the ocean releases most of its absorbed energy back out into this atmosphere by way of evaporation to stay in balance with its incoming from the Sun.
This means that on real Earth, the water surface will reach its steady state temperature long before <em>radiative</em> balance has been accomplished, i.e. as much energy is released from the surface as taken up by the volume of water per unit of time even at much lower temperatures than the ideal Stefan-Boltzmann blackbody situation would seem to demand. Courtesy of the release of latent heat through evaporation.
So yes, it would seem that putting an atmosphere on top of a water surface would enable it to reach its heat IN/OUT balance point at a lower steady state temperature than without such an atmosphere. This, however, is not because the evaporative loss comes IN ADDITION TO the radiative loss. It is because it comes INSTEAD OF a large part of the previous radiative loss.
You see, emissive power from a surface is only a function of its temperature and emissivity alone if that surface happens to be a pure/ideal emitter, that is, its entire heat loss comes via radiation, meaning it's isolated in a vacuum at 0 K or simply very much hotter than its surroundings. There is nothing in the Stefan-Boltzmann equation suggesting otherwise. The S-B law applies only to purely radiative situations. Just like Planck's and Kirchhoff's laws do. The idea that it applies no matter what has no empirical basis and it ignores simple energy budgetting principles.
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Comment on Gravito-thermal discussion thread by Ragnaar
Is it true that this is like talking about balance sheets and income statements? Starting with Eschenbach’s example a 3 watts incoming planet. Adding any kind of gas at most delays radiation back to space. Any GHG effect is simply borrowing. It’s having a policy of holding all bills for two weeks before paying them so that we have short term cash or heat. Assume the gas has some vertical gas circulation. That’s not income. It is a transfer like from a money market to a checking account. In the end I think the books must balance. Beginning stuff plus changes equals ending stuff.
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Comment on Gravito-thermal discussion thread by DocMartyn
Why use a vacuum?
Why not use CO2 to reflect the IR back into the thermos?
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Comment on Gravito-thermal discussion thread by Rob Ellison
The atmosphere – not active in the IR bands by assumption – would be warmed by conduction and convection. The energy would accumulate until emissions again balanced incoming energy. You would need to know the makeup of the ‘atmosphere’ to have any idea of the atmospheric physics which is where it all becomes inuterably ridiculous.
What you need to do is divest yourself of the notion that strange little thought experiments explain anything interesting at all.
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Comment on Gravito-thermal discussion thread by Stephen Wilde
Yes, if you add GHGs they allow radiation to space from within the atmosphere which is earlier expenditure than if it were returned to the surface in convective descent before being radiated out to space.
Then the energy having been lost to space (spent) the convective descent returns less to the surface than was taken up in the ascent so there is net deficit (cooling).
But the convective overturning having been weakened the atmosphere contracts a little which increases density at the surface and that increased density picks up more energy from the surface (earned) and that balances the expenditure from GHGs.
But since it is all about mass in the first place you would never notice the variation caused by GHGs. It would disappear in the rounding.
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Comment on Gravito-thermal discussion thread by Rob Ellison
This topic is so endlessly silly – even Miskolczy is a welcome distraction.
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