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Mike Hillis at 09:21 AM on 19 June 2016Venus doesn't have a runaway greenhouse effect
Michael sweet @144
Keep in mind that Steve Goddard thinks CO2 can fall as snow at the south pole and be sequestered there forever.
That is an error. This is what Steve Goddard actually says:
https://stevengoddard.wordpress.com/2012/06/12/antarctic-temperature-drops-below-the-freezing-point-of-co2/#comments
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Mike Hillis at 09:01 AM on 19 June 2016Venus doesn't have a runaway greenhouse effect
@ 145
Are you saying that adiabatic processes can’t change the total heat content in the atmosphere of Venus (or any other planet) and that the high temperature near the surface is only caused by a redistribution of heat?
Yup. Only the sun can change the total heat content of the atmosphere.
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Mike Hillis at 08:51 AM on 19 June 2016Venus doesn't have a runaway greenhouse effect
@144
Heat and temperature are directly proportional in a given parcel of air.
Yes, as long as you don't change the pressure or volume, which can change the T without changing heat content. High school chemistry teachers should know this.
pV = nRT says if you increase PV, the T goes up even though you have not added heat. The work done to change the parcel's elevation and raise or lower the PV is uneven solar heating of the atmosphere.
I will not state my argument again because repeating oneself is against comments policy.
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RedBaron at 08:33 AM on 19 June 2016Human CO2 is a tiny % of CO2 emissions
William,
Most likely the soil causing it. That's good news and bad news. The good news is that it is reversable. The bad news is that we are fairly unlikely to do so. As although it really is easily reversable, there is a huge institutional resistance to even trying, and actually the trends are to accelorate it rather than mitigate it.
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RedBaron at 08:17 AM on 19 June 2016Timeline: How BECCS became climate change’s ‘saviour’ technology
Getting closer, not quite there yet. Next step is forget putting CO2 in geological formations. The carbon needs to be in the soils. But it is doable.
Technical Brief: The Liquid Carbon Pathway
Now the Liquid pathway alone gets you between 5-20 Gt CO2/ha/year. (the 32 Gt CO2 mentioned in the source is a bit of an outlier. Yes people are getting those results and even better in some cases, but 5-20 is more common) That alone if used on enough agricultural land would sequester long term in the soil between 62% to 250% world wide yearly fossil fuel emissions. But since biochar is carbon too, and in a stable form, there is even more. Since making biochar can produce energy too...... This would be the next step...if things like solar and nuclear couldn't keep up.
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HK at 08:07 AM on 19 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis @143:
"Adiabatic changes in temperature don't add or lose total heat...."Are you saying that adiabatic processes can’t change the total heat content in the atmosphere of Venus (or any other planet) and that the high temperature near the surface is only caused by a redistribution of heat?
(A short yes or no is sufficient)
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michael sweet at 07:31 AM on 19 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hills,
Your arguments started out interesting but have gone way down. I suggest you review basic chemistry and physics before you post again. You need to stop reading from the blog source you are getting your information from. Keep in mind that Steve Goddard thinks CO2 can fall as snow at the south pole and be sequestered there forever. If you want to convince readers here you have to get the High School Chemistry (which I teach) correct.
Heat and temperature are directly proportional in a given parcel of air. If the temperature increases as the parcel as it sinks, the heat increases. The heat has to come from somewhere. It cannot come from the parcel itself as that would violate the first law of thermodynamics. Glenn's explaination that the energy comes from the work the surroundings does (or that a rising parcel does on the surroundings) is the correct one. Read his post again if you are unclear about where the heat comes from.
Venus is the classic example of a runaway greenhouse effect. Arguing that Venus is not a greenhouse planet will not get you any converts at a scientific site.
Can you find a scientific reference (paper or textbook) that caims Venus is not a greenhouse (I note that you have not referred to any scientific papers in your arguments, only blog science)? If you cannot perhaps you should consider that it is because Venus really is a greenhouse and your blog science is incorrect.
Your claim that heat can be transferred from the cold upper atmosphere to the warmer lower atmosphere is also a violation of the laws of thermodynamics.
I will try not to comment again since dogpiling is against the comments policy.
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Ger at 01:32 AM on 19 June 2016Timeline: How BECCS became climate change’s ‘saviour’ technology
chriskoz @2: most CO2 plants do take in is from rotting materials in the ground/on the ground. Most agricultural residues represent for the larger part the fast amount needed: for England alone there is a 14 million tons a year, relative easy, to obtain mass representing a 140 million GJ in primairy energy. And most agricultural is still for food (arable lands for food are still available).
Hungry world is struggeling not that they don't have arable lands but that modern high productive crops do need far more water and fertilizers per ha for which the farmers lack investments. Furthermore they lack the means to create the risk mitigation measurements for a planet heating up, especially in regions where it is already hot and with less water.
Greenhouses in hot & dry areas near sea's can turn a dessert in a food production area. Any CO2 can be used to enhance growth of plants in hydrocultures. You don't need much more, except for a ship load of investments.
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chriskoz at 00:45 AM on 19 June 2016Timeline: How BECCS became climate change’s ‘saviour’ technology
Digby@1,
We made a little bit of progress with our ideas about CO2 capture. I think CCS (old term) and BECCS are diferent concepts. CCS, also refered to as "clean coal", was an excuse by mining moguls to promote burming more FF, becaue we can, in theory, burn it "clean" i.e. do not emit CO2 into atmosphere. The idea is best debunked and ridiculed by aSkS post Sequestering carbon nature's way: in coal beds, esp. its graphic.
Now, BECCS is something totally different: shows that it's possible to net remove CO2 from atmosphere - employing fast growing biomas - burn the biomass and store captured CO2. And the beauty of the concept is: you obtain energy from the process, unlike in "clean coal" where you assume to input energy into the process, presumably coming from the coal itself, reducing its thermal efficiency, so making it even more "dirty" than it was in the first place. However, I'm still skeptical how realistic is the deployment of BECCS on the scale needed. The amount of biomass cycling must be enormous, because the its energy density is smaller than that of quality coal (we sgopped burning wood to charcoal in favour of mining coal in 19th century precisely for that reason), and if there is enough land to grow said biomass, then an efficient way to gather it and bring to BECCS facilities and enough power is left to compress and store CO2 underground. That requires big infrastructure. Just raising such infrastructure requires lots of money and energy. How many years does it need to operate to break even on CO2 emissions?
The existing PV technology, although it's not negative emmsions, offsets its production emissions after ca. 1 year of its life. I'm not so sure about BECCS. In practice, BECCS may turn out to be utopia, because simply there is no enough land to start with B, while hungry world is struggling to turn every arable land for food production. Needless to say cobtinue with ECCS...
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Mike Hillis at 23:49 PM on 18 June 2016Venus doesn't have a runaway greenhouse effect
Adiabatic changes in temperature don't add or lose total heat, because when the volume goes down the T goes up so total heat in parcel remains the same. Just the temperature changes. The amount of heat in the parcel of air remains the same, all that changes in the temperature and volume according to
PV = nRT
So if PV goes up, T goes up, but when the temperature goes up the total heat contained stays the same because the volume goes down. That's how it works. Heat stays the same and volume goes down, the temperature goes up. Follow with me closely:
1. Parcel moves down and compresses
2. Heat stays the same but T goes up
3. Parcel equilibiates T with lower elevation surrounding air by adding heat to it
4. Parcel moves up and expands
5. Heat in parcel stays the same but T goes down
6. Surrounding air adds heat to parcel to equilibriate T
All heat added to parcel from surrounding air is at higher elevation, all heat lost from parcel is at lower, so heat is moved from high elevation towards low until it reaches the surface.
This is for ALL vertical motion of air, whether is be large air masses, small parcels, or brownian motion, and at any and all elevations.
And since horizontal motion of air is many times faster than vertical, the air parcels are quickly moving around the planet, which is why the poles on Venus are the same temperature as the equator, and the night side is at warm as the daylit side.
Glenn @ 142 says
this energy has to come from somewhere. And the only energy source available is the internal energy of the rising air parcel
No, the source of energy is the Sun
Moderator Response:[RH] Please avoid using all caps, per comments policy.
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Glenn Tamblyn at 18:05 PM on 18 June 2016Human CO2 is a tiny % of CO2 emissions
william
I would think its most likely an effect of El Nino. Even if carbon sinks start to shut down, they wont be that precipitous. -
Tom Curtis at 17:15 PM on 18 June 2016Climate scientists have warned us of coral bleaching for years. It's here
pjcarson2015 @4:
"Incidentally, in my previous post I referred to chapters in my site, “Planet Earth Climate Topics” at ..."
Yes. As always you spammed an add for your site which contains, as usual, a great paucity of facts, a significant number of inventions, and a curious refusal to correct errors. On this topic it contains no information in addition to the text of your post @3 and therefore is not an independent source of evidence, or indeed a source of evidence at all.
As to your post @3, yes coral recovers from bleaching. Recovery, however, takes time. If there are repeated impacts during that time, recovery will be slow, or not occur at all. As can be seen below, events causing damage to reefs have accellerated in recent times, and for the Great Barrier Reef, that has lead to a long term decline in coral cover (second figure):
(Source)
(Source)
As you can see, that decline has been precipitous for the southern most (and most disturbed) portion of the reef.
What is worse, as can be seen from calcification studies, that decline comes at the tail of a reversal of a century long increase in reef health in the mid 20th century (figure d):
Granted that bleaching events currently account for only 10% of reef damage. However, the GMST during the last bleaching event was less than the 2 C limitation on global warming aimed at by international agreements. If global warming is restricted that limit (currently very unlikely on present policies), that means we will be getting multiple equivalent bleaching events every decade within fifty years. That is far to rapid a pace to recover from, so that bleaching events alone would be sufficient to destroy most of the Great Barrier Reef.
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Digby Scorgie at 15:14 PM on 18 June 2016Timeline: How BECCS became climate change’s ‘saviour’ technology
Professor Kevin Anderson has some scathing things to say about BECCS. I'm also reminded of the article by Andy Skuce on 13 January 2016: "The quest for CCS". At best it is just a stopgap measure.
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Glenn Tamblyn at 12:52 PM on 18 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis at @135
"as I already said, as the air moves down it adds heat to the air it decends to. As it ascends, it takes heat from the air it ascends to. In BOTH directions, it transfers heat from higher to lower"
Actually Mike, you have this back-to-front. As air moves down heat is added to it from the surrouning air. And as air rises heat is removed from it by the surrounding air. You are leaving important aspects of the problem out - potential energy changes and work.
A parcel of air that is rising in the atmosphere is being lifted by some force, air pressure, buoyancy, whatever. So work is being done on it. However, because it is rising, the air parcel is also gaining potential energy. When we work out the math, the work done on the parcel exactly matchs the potential energy gain. So conservation of energy says no net change in the energy of the parcel. At the scale of air movements in the atmosphere there is little mixing between parcels, so no scope for significant heat transfer between them And in a dense atmosphere radiative transfer is very poor. So the movement of the air parcel is essentially adiabatic - no net heat flow in or out.
So the parcel would rise to a higher altitude essentially unchanged same volume, same pressure, same temperature. However, pressure can't stay the same. At higher altitude air pressure is lower, and air pressure must equalise. So the parcel has to expand to equalise pressure with the surrounding air. But in order to expand the parcel has to push the other parcels around it aside to make room for its expansion. It has to do work on them. So there is an energy transfer from the rising parcel to the surrounding air as work. But conservation of energy says this energy has to come from somewhere. And the only energy source available is the internal energy of the rising air parcel. In order to supply the energy needed to push other air parcels aside, the rising parcel loses internal energy. Its temperature drops as it transfers energy to its surroundings.
For descending air parcel it is the reverse. as it descends, pressure equalisation means that the surrounding air compresses the parcel, doing work on it, adding to its total energy which since the situation is adiabatic can only manifest as an increase in the temperature of the parcel.
Rising air heats its surroundings and is thus cooled by them, falling air is heated by its surroundings and cools them. -
pjcarson2015 at 11:14 AM on 18 June 2016Climate scientists have warned us of coral bleaching for years. It's here
You replied as Moderator. Which facts and observations in my post are an issue?
[Incidentally, in my previous post I referred to chapters in my site, “Planet Earth Climate Topics” at pjcarson2015.wordpress.com]
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HK at 08:13 AM on 18 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis @136:
My point is that Venera’s measurements clearly show that the IR radiation escaping from Venus can’t come from near its surface, but from much colder and therefore much less radiating layers in its upper atmosphere.
If the high temperature was caused by any physical process that adds heat rather than slows down the heat loss to space (as the GHE does), the spectrum of the outgoing IR from Venus would look completely different. Using the wavenumber scale (as done in the graph), the peak radiation would be more than 20 times higher (thus the need to enlarge the y-axis!), and shifted to about 1440 cm-1.BTW, the 15 µm band (667 cm-1) is important for the Venusian greenhouse effect exactly because almost all the heat loss to space happens from the very cold, upper layers of the atmosphere and not from near the surface.
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william5331 at 07:40 AM on 18 June 2016Development banks threaten to unleash an infrastructure tsunami on the environment
To understand what is happening you can read the updated version of Confessions of An Economic Hit Man by John Perkins and The creature from Jekyll Island by Edward Griffin. The Secret History of the United States by Stone is also very revealing. In a sentence, The world Bank has little to do with the world except that it is a mechanism for America to exploit the world and increase its hegemony over it. Huge loans are made to countries that can't possibly repay them and when they default, America gets her pound (more like a ton) of flesh. Countries are forced to privatize their services which American corporations snap up. Favorable votes in the UN are also sometimes the currency of repayment. Right at the base of it is that banks hate when countries, businesses and individuals finance their advancement from their own profits. They want to give loans because that is how they make their money. They will put pressure on wherever they can to achieve this aim. Griffins book, in a very readable and clear fashion, shows what a scam the Federal Reserve (and other reserve banks) are.
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scaddenp at 07:39 AM on 18 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis, just to be clear here - do you believe that if you put venus atmosphere into an ordinary GCM using only known physics, then the temperature and isothermal structure of surface is not reproduced?
ie it is "unexplained" by known physics?
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Tom Curtis at 07:29 AM on 18 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis @135, you also said:
"Tidal forces and the friction it gererates will eventually stop the rotation of Venus, but until then, the motion, all motion, within its atmosphere, will continue to generate heat katabatically."
What you should have said is that, "until then, the motion, all motion, within its atmosphere, will continue to generate and remove heat in equal proportions katabatically" unless you take the delussory view that all atmospheric motion on Venus is downward.
What this mechanism does, and the only thing it does, is to generate the lapse rate in the troposphere. That is, it establishes a linear relationship between the temperature difference and distance along the vertical axis within the troposphere. It cannot, by itself, determine the exact value of the temperature at any point in the troposphere.
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william5331 at 07:22 AM on 18 June 2016Human CO2 is a tiny % of CO2 emissions
According to some reports, we didn't emit more Carbon dioxide in 2015 than in 2014. Perhaps our output has leveled off or may even decrease as more and more energy saving, renewable generation and a flat economy take hold. I find this frightening. If you look at the Mana Loa Carbon dioxide site for April, Carbon dioxide went up 4.16ppm despite this lack of increased carbon output. All things being equal one would have expected, possibly, a 2.5ppm increase. Apparently all things are not equal. Is this some effect of the strong El Nino we experienced or have one or more carbon sinks started to shut down. If this continues to the end of 2016 and into 2017, we just may be in a spot of bother. All things being equal, we would expect the line to revert to the long term increase and should see some quite small increases on into 2017.
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Mike Hillis at 07:20 AM on 18 June 2016Venus doesn't have a runaway greenhouse effect
And just to be clear on Tom Curtis @ 133:
"Given that, the idea that after 4.6 billion years there continues to be a net settling of the atmosphere that is needed to generate excess heat is absurd."
We are not talking about generating heat. We are talking about transferring heat, in this case, transferring it from every layer of the atmosphere to the surface. The heat comes from the sun, absorbed by the atmosphere so that only 10% of the light that falls on Venus ever reaches the surface. The bulk of the heat is transferred to the surface by the gravity heat pump mechanism I described.
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Mike Hillis at 06:11 AM on 18 June 2016Venus doesn't have a runaway greenhouse effect
2 and 3 and 4.5 I meant
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Mike Hillis at 06:10 AM on 18 June 2016Venus doesn't have a runaway greenhouse effect
HK @ 134 Venus is much hotter than Earth and radiates at shorter wavelengths, so we can pay more attention to the 2 and 3 4.5 micron bands and less to the 15 mike band. Take another look at the graph.
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Mike Hillis at 06:07 AM on 18 June 2016Venus doesn't have a runaway greenhouse effect
Tom @ 133 as I already said, as the air moves down it adds heat to the air it decends to. As it ascends, it takes heat from the air it ascends to. In BOTH directions, it transfers heat from higher to lower. Read again what I said.
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RedBaron at 03:27 AM on 18 June 2016Study: Most fossil fuels unburnable without carbon capture
There is somewhere between 35 and 40 Gt CO2 emissions yearly worldwide. To draw down CO2, (decrease the stocks in the atmosphere) we must adjust the flows into and out of the atmosphere until we achieve a net negative flux.
There are approximately 5 Giga Hectares of land in the world currently being used to produce food for human populations. (only ~1%+/- is in permaculture or other ecofriendly management) Agriculture has been proven to be capable of being an emissions source or a sequestration sink depending on the methods used. Currently right now agriculture is an emissions source. (99% being managed by either industrial or traditional subsistence methods)
Working backwards, for agriculture to offset emissions and achieve a net negative flux for atmospheric CO2 worldwide each hectare of agricultural land producing food would need to sequester long term into the soil over approximately 8t CO2/year. 8t CO2/ha/year X 5 Gha = 40Gt CO2/year
Can we do that? According to Dr. Christine Jones we certainly can.
Liquid carbon pathway unrecognised
The case studies mentioned by Dr. Christine Jones above show a range in results between 5 & 20 tonnes CO2e/ha/year increases in soil carbon by using permaculture pasture cropping methods. (direct seeding grain crops into perennial pasture and cell or pulse rotational grazing integrated together)
Why pasture cropping is such a big deal
In no way is this example alone or even out of the ordinary. There are multiple case studies on people getting similar results with other carbon farming practises.
So quite likely if done on enough land we could offset between 62% and 250% of all emissions worldwide. That is VERY conservative BTW, because it doesn't even include the oceans or the forests which already are removing about 1/2 of the ~35 to 40 Gt CO2 emissions yearly worldwide.
Makes me wonder why CCS technology is even being discussed? We know soil degradation is a very serious problem.
Only 60 Years of Farming Left If Soil Degradation Continues
We also know renerating degraded soils includes restoring Soil Organic Carbon (SOC)
So no, CCS technologies is a fail from the start whether it works or not. We actually need that carbon... But we need it in the soils worldwide, not some CCS technology. It's a very bad idea and pulling resources away from where it needs to be...implementing the infrastructure required to change agricultural models of production to regenerative systems.
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HK at 00:02 AM on 18 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis:
Did you check out KR’s link in @123? Look at figure 3c on page 4 (lower left). The red curve shows measurements by the Soviet Venera 15 probe of outgoing IR radiation from Venus.Do you have any idea of what that curve would look like if the extreme temperature on Venus was caused by gravitational compression – or any other heat source – rather than IR absorption in the atmosphere?
Hint: You would have to expand the y-axis a lot!
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Tom Curtis at 22:34 PM on 17 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis @132, don't be a fool. Downward motion of air heats the air, but upward motion of air cools it. If the same amount moves up as down, there is no net heat generated, and hence no possibility that this mechanism will raise temperatures above what they would have been from solar input alone. As it happens, convective equilibrium is achieved within hours in the troposphere. Given that, the idea that after 4.6 billion years there continues to be a net settling of the atmosphere that is needed to generate excess heat is absurd.
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Mike Hillis at 21:51 PM on 17 June 2016Venus doesn't have a runaway greenhouse effect
Tom Curtis 131
The atmospheres of rocky planets, including Earth and Venus are very thin, and have reached quasi-equilibrium a long time ago. Ergo, no net conversion of potential energy to kinetic energy, and no overall warming of the atmosphere by gravitation. End of story. Your explanation is a non-starter, and shows all the accumen demonstrated by various inventors of perpetual motion machines (which it would allow, if valid).
Quasi equilibrium is not equilibrium. Small motion, even brownian motion, is enough. All small parcels of gas, even single molecules, generate heat on the way in and release it on the way out. Gas moves in, compresses, heats up, releases heat to the neighboring gas at lower elevation, moves back up, cools, absorbs heat from neaghboring gas at higher elevation, moves back down, etc. If you don't understand how vertical movement of gas generates heat and transfers it in a downward direction, then you probably don't understand why Death Valley is so hot, or why the San Gabriel and Santa Ana winds heat up as the elevation decrease, even at night. These are called katabatic winds https://en.wikipedia.org/wiki/Katabatic_wind and happen all over Antarctica. In the extreme, as on Venus and Jupiter, they explain everything. Taken to the extreme extreme, near the core of Jupiter, the temperature is 20,000 K. and the Kelvin Helmholtz theory isn't even necessary (that theory requires permanent compression....not needed).
Please no talk about perpetual motion machines. The solar system has been in motion for only 4.6 by, and that's a long time but not perpetual. Tidal forces and the friction it gererates will eventually stop the rotation of Venus, but until then, the motion, all motion, within its atmosphere, will continue to generate heat katabatically.
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Tom Curtis at 17:47 PM on 17 June 2016Venus doesn't have a runaway greenhouse effect
Returning to Mike Hillis @ 121:
1)
"The greenhouse effect doesn't explain why the dark and sunlit sides of Venus are the same temperature, and why the poles are as hot as the equator."
Actually, it has been predicted since Svante Arrhenius in 1896 that increasing the greenhouse effect will warm the poles more than the equator, in winter more than in summer, and it has also been shown that the greenhouse effect warms nights more than days. Carried to extremes, these features easilly explain why Venutian nights should be as warm as days, and polar regions as warm as tropical regions in the lower troposphere. In contrast, no presentation of the theory you appeal to purports to show the same thing.
2)
"This does"
The blog post for which you provide a link appeals to a paper showing temperature hotspots at high altitudes to prove that the adiabatic lapse rate applies throughout the entire atmosphere. That is, it appeals to a paper that falsifies its claim as proof of that claim. It further claims the existence of the adiabatic lapse rate (where it exists) is proof of their preferred theory (of which more in a later post) even though it is a well known feature, and an important feature of the standard greenhouse theory since Manabe and Wetherald (1967), and a well known feature of all atmospheres in regions dominated by convection long before that.
3)
"Venus is not like earth, in that its atmosphere directly absorbs sunlight on the way in, via the H2SO4 clouds."
In fact measured solar flux on the Venutian surface is between 35 and 40 W/m^2 at the surface (see figure 6). On the other hand, global mean net solar flux (accounting for differences in latitude, season and the day night cycle) in only about 8 W/m^2. Both of these are substantially smaller than is the case on Earth, due to the thick cloud, but they are more than sufficient to generate an adiabatic lapse rate in the Venutian troposphere (as is proven by its existence). If all solar heating was dissipated in the clouds, as you claim, the surface would be cooler than the clouds, just as the tropopause is cooler than the stratosphere due to the heating of ozone in the stratosphere by UV radiation on Earth. That is, if you were right about this point, the very precondition for validity of your preferred (in not understood) theory would be false.
4)
"The reason the temperature everywhere on Venus is the same is, gravity is the same all around Venus."
The only way gravity 'generates' energy, and hence raises temperatures, is the conversion of gravitational potential energy to kinetic energy by masses falling towards the surface. For an atmosphere in equilibrium, there is no net infall of material, and hence no net energy conversion from potential to kinetic forms. The atmospheres of rocky planets, including Earth and Venus are very thin, and have reached quasi-equilibrium a long time ago. Ergo, no net conversion of potential energy to kinetic energy, and no overall warming of the atmosphere by gravitation. End of story. Your explanation is a non-starter, and shows all the accumen demonstrated by various inventors of perpetual motion machines (which it would allow, if valid).
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Glenn Tamblyn at 15:54 PM on 17 June 2016Venus doesn't have a runaway greenhouse effect
Also Mike.
The forcing effect of CO2, at so much per doubling, isn't the same ratio all the way up to those very high concentrations. Additional wavelengths come into play at those higher concentrations, a process called Continuum Absorption comes into play, and the Lapse Rate of the atmosphere of Venus is more like 10.4 Deg C per km vs 6.5 here on Earth. Also there is SO2 present on venus that isn't present here on Earth. And since there is cloud covering the entire planet, not just part of it even though SO2 clouds aren'e as effective as emitters as water clouds, this still produces a bigger GH effect from clouds than here on Earth. Since the Bond Albedo of Venus is around 0.9 - 90% reflection, much from those clouds, the GH effect impact of those clouds would also be substantial.
You can't extrapolate simply from the current climate on Earth, you actually need to run the radiation modelling programs with venus's atmosphere to get the correct result.
From the post above "In the dense Venusian CO2 atmosphere, pressure broadening from collisions and the presence of a large number of absorption features unimportant on modern Earth can come into play (figure 1b), which means quick and dirty attempts by Goddard to extrapolate the logarithmic dependence between CO2 and radiative forcing make little sense."
A better way of thinking about it, is to use the radiation calculations to determine what the effective radiating height for the atmosphere is, the average altitude that radiation to space originates from. For the Earth that is around 5 km up, for Venus it is over 50 km up. The average temperature at that altitude will be at around the effective radiating temperature the planet needs to be at to be in energy balance. For the earth that is -18C. For Venus it is more like -80 - -90 C. So a lapse rate of 6.5, over a 5km altitude makes the surface of the Earth around 32.5C warmer than the effective emission level so around 14-15C.
For Venus, a lapse rate of 10.2 approximately and an effective emission height of over 50 km gives a surface temperature something of the order of 510-550 C warmer that the effective emission level, so the surface temperature should be something like 420-470C. -
Tom Dayton at 14:42 PM on 17 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis, Skeptical Science is not intended to be an encyclopedia. You need to exert A little independent effort before posting your off topic diatribes.
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Mike Hillis at 13:56 PM on 17 June 2016Venus doesn't have a runaway greenhouse effect
How many times would we have to double Earth's CO2 to be the same as Venus, which is 96% CO2 and is 93 times denser than Earth's? The answer is 18. Starting at 400 and doubling:
800
1600
3200
6400
12800
25600
51200
100k
200k
400k
800k
1.6m
3.2m
6.4m
12.8m
25m
50m
100mWith a climate sensitivity of 2C per doubling, Earth would only be 2 x 18 or 32 C warmer than it is now, using the greenhouse effect of CO2
Moderator Response:[RH] Try using central estimates for CS of 3°C.
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Mike Hillis at 13:38 PM on 17 June 2016Venus doesn't have a runaway greenhouse effect
Lots of posturing, yet no explanation why the poles of Venus are as hot as the equator, why the night side is as hot as the day side, and why Jupiter, which has an atmosphere made of H2 and He which are not greenhouse gases, has a temperature of 260 F at a depth in the atmosphere where the P is 11 bars.
Moderator Response:[RH] Need I remind you that you are currently skating on thin ice with regards to your commenting privileges. Posting links to blog posts instead of published research and then calling published research "posturing" does not help you. Stick to the published research, if there is any, to support your position, please.
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Glenn Tamblyn at 12:44 PM on 17 June 2016Venus doesn't have a runaway greenhouse effect
It always amazes me how many people get the Ideal Gas Law wrong with the 'Pressure causes Temperature' idea. But explaining it never helps, they just don't get it.
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pjcarson2015 at 10:39 AM on 17 June 2016Climate scientists have warned us of coral bleaching for years. It's here
Currently there is anxiety about coral bleaching, affecting particularly the northern Great Barrier Reef. Valerie Taylor had a short informal interview in The Weekend Australian’s Magazine, May 14. You may recall she made many documentaries with her husband Ron about sharks. She’s now 80, and still dives. [Current researchers would/should have been aware of their well known documentaries.] She says of the GBR,
“In 1965 we went from one end of the reef to the other, over six months, and we found bleaching then. In the ‘70s we went back and you’d never know it happened. The coral had recovered; nature had taken care of it. I’ve seen reefs in PNG that were as white as snow and I’ve just come back from there and they’re terrific.”
She thus observes that bleaching is reversible. (Presumably spores from unaffected corals can flow in again to re-colonise affected areas once the cause has departed.)
Coral bleaching and repair occur independently of atmospheric CO2 levels.
As it is mainly the relatively untouched northern areas of the GBR affected, it is unlikely that run-off is the cause. The current bleaching decreases towards the south, flowing on the north-to-south counter-clockwise current from Vanuatu, and becoming depleted in the process. Upstream undersea volcanic activity around Vanuatu produces toxic H2S (Chapter 4a, Cyclone Pam), in time oxidising to sulphuric acid, which may also be a concern; Chapter 5 shows acidity produced by CO2 is not.
Other coral bleaching areas around the globe, eg Seychelles, Caribbean, Maldives, etc are downstream from undersea volcanic areas.
Moderator Response:[Rob P] Coral reefs are dying out at the rate of 1-2% per year, and it's very much 'settled science' that the mass coral bleaching and subsequent mortality that we are observing is as a result of sea surface temperatures rising above their normal summertime maximum. See Ove Hoegh-Guldberg's 1999 paper for a detailed rundown.
This why NOAA's Coral Reef Watch program can reliably predict bleaching events some months in advance. The bleaching of the Great Barrier Reef, and elsewhere, was predicted 3-4 months before it happened, and their climate model-based projections anticipate extraordinary bleaching in the Coral Triangle later this year. -
Rolf Jander at 08:43 AM on 17 June 2016Development banks threaten to unleash an infrastructure tsunami on the environment
"Good Bye Mother Nature"
The Guess Who.
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MA Rodger at 08:27 AM on 17 June 2016Venus doesn't have a runaway greenhouse effect
KR @123.
The Nikolov and Zeller poster is not entirely make believe. Their initial modelling of a planet with zero GH-effect is correct but is so silly with its assumptions I wasn't bothered to look further into their arguments. So I cannot speak for how bad the rest of it is.
That initial model in 2.1A is for a planet with its day-side locked to always face the sun. The average temperature will thus be a little over half the black body temperature. And this should not be a great surprise; with its dark side permanently unheated, half the planet has a temperature effectively at absolute zero. Smith (2008) helpfully have done these sums & show the effects of rotation & thermal inertia.
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scaddenp at 07:32 AM on 17 June 2016Venus doesn't have a runaway greenhouse effect
Gee, I am surprised this rubbish keeps coming up, when it was laughed at even in "skeptic" circles. You might like to read what Roy Spencer has to say on the subject as I suspect you would trust that source rather than "warmistas" here or say physics textbooks. This has come up here before and even our friend Camburn wouldnt buy it. If you think this is plausible, then I think he has a bridge he would like to sell you.
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william5331 at 06:10 AM on 17 June 2016New study finds evidence for a 'fast' dinosaur extinction
Pretty convincing. The Iridium data from his site would be pretty well the clincher.
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knaugle at 05:53 AM on 17 June 2016Development banks threaten to unleash an infrastructure tsunami on the environment
Consider that there is some thought that Biscayne Bay area of Miami will be uninhabitable in 30 or 40 years because of rising sea levels and the rather porous substrate. Yet right NOW there is a building boom. Why? I've read that it's because developers calculate that it takes 20 years for them to turn a profit and they will be long gone before it's a problem.
So the question is. Did I get this right? Or am I making it up? -
Alexandre at 04:18 AM on 17 June 2016Development banks threaten to unleash an infrastructure tsunami on the environment
There's a hydroelectric dam here in Brazil that's been a long controversial issue. It's the Belo Monte Dam, that is on a flat land in the middle of the Amazon forest, and therefore needs a large flooded area for a relatively small amount of electricity generated.
Even before the present political crisis (president Rousseff is in the middle of an impeachment process), the environmental issues were quite low down the priority list: the minister who was responsible for the dam was one of the few overt climate denialists in Brazilian politics.
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KR at 03:02 AM on 17 June 2016Venus doesn't have a runaway greenhouse effect
That Nikolov and Zeller poster, not to mention the related Hockeyschtick blog post, could best be summarized as:
"We didn't like GHG physics, so we made up our own."
In short, utter nonsense. If you want actual physics, I would suggest reading the quite approachable Pierrehumbert 2001 article, "Infrared radiation and planetary temperature".
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MA Rodger at 02:46 AM on 17 June 2016Venus doesn't have a runaway greenhouse effect
Mike Hillis @121.
You are incorrect in presenting that link to a denialist webpage while proclaiming "The greenhouse effect doesn't explain why .... . This does:" The link you provide offers no explanation but rather presents unsubstantiated assertion spruced up with a couple of sweeps of Ockham's broom. The nonsense is explained however (as much as such things can be explained) by Nikolov and Zeller's 2011 conference poster.
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dvaytw at 00:40 AM on 17 June 2016Temp record is unreliable
Thanks guys. Scaddenp, I looked up the Monte Carlo method, but that stuff is way over my head. The main issue of the guy you suggested is being willfully-ignorant (I agree) is that he doesn't see how a single fact about the past can be expressed as a probability. He quoted the definition of probability to me:
A number expressing the likelihood of the occurrence of a given event, especially a fraction expressing how many times the event will happen in a given number of tests or experiments.
and asked how such an expression could fit the definition. I suggested to him that here, "probability" means something like, 'given similar amount and kinds of evidence plus measurement uncertainty, if we ran the calculation multiple times, what percentage of the time would the calculation be correct'. Is this basically right?
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Mike Hillis at 23:20 PM on 16 June 2016Venus doesn't have a runaway greenhouse effect
The greenhouse effect doesn't explain why the dark and sunlit sides of Venus are the same temperature, and why the poles are as hot as the equator. This does:
http://hockeyschtick.blogspot.com.au/2016/06/new-paper-demonstrates-gravito-thermal.html
Venus is not like earth, in that its atmosphere directly absorbs sunlight on the way in, via the H2SO4 clouds. That heat absorced by H2SO4 is transferred to the surface via the gravity pump described here.
The reason the temperature everywhere on Venus is the same is, gravity is the same all around Venus.
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Glenn Tamblyn at 18:41 PM on 16 June 2016The Grand Oil Party: House Republicans denounce a carbon tax
Just throwing in my two-penn'th worth.
Cap and Trade has one really good feature and one really bad feature.
Cap is good because it is directly targetting what we need to do - capping emissions. Carbon taxes in contrast don't actually target that. They put a price on emissions and basically hoe that will achieve the effect of a cap.
Trade, not so good. In the simplistic world of economists, trade, markets etc produce 'efficiency'. Often this efficiency doesn't actually translate to social utility. And there is one key problem. A lot of very smart people get up every day to strive as hard as they possibly can to subborn the market, twist it, break it to their advantage. Trade is probably just a huge 'employment opportunity' for financial engineers.
The idea of making any approach revenue neutral is sounc. Cap and Dividend, conceptually seems the right approach. Cap gives certainty and Dividen makes it revenue neutral.As to using regulation, there are good arguments for regulations, highly targetted, in very specific contexts. They actually need to be simple regulations, targetting key industry sectors. Two key ones:
- Electricity generation. We don't need masses of regulations, just some simple rules and clarity.
- Fuel Efficiency standards. By simply saying that vehicle efficiency standards need to rise steadily, ultimately they are saying a switch to non fossil fuels is needed. Petrol to Hybrid to Electric delivered via an indirect measure. Unleash the California Air Resources Board (CARB) to set standards for California, and that becomes the defacto standard for the US, which then becomes a defacto standard for the world. CARB has done this before.
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Tom Curtis at 10:19 AM on 16 June 2016The Grand Oil Party: House Republicans denounce a carbon tax
CSM @16, with respect, the US does not have a significant debt crisis. The measure of whether or not your debt is unmanagable is your ability to pay of the interest, which is currently 223 billion US dollars (6% of the Federal budget). That is an affordable amount, and just paying of the interest will result in a 2-3% decrease in the debt/GDP ratio per annum on average based on economic growth. If most of the debt is in US dollars, inflation will decrease the real value of the debt even quicker.
The US is portrayed as having a debt crisis by comparing its national debt to its national income. However, for private corporations and individuals, the comparisons made are total debts to total assets (the later typically being ten times the value of income); or of repayments to income (where the former need only include interest repayments). The use of debt to GDP comparisons represents a double standard. If applied to industry, for example, it would require that businesses by wound up if their debt exceeds their income, which would be ridiculous.
The US does need to balance its budget, but it needs to do so in a way that will keep the budget balanced in the long term and over the course of the economic cycle. Temporary budget measures are not the way to achieve that, and certainly a measure which is designed to decrease its revenue to zero over time will not achieve that except temporarilly. Further, if it is revenue neutral, it will not accomplish that in any event.
What using such a measure to balance the budget would achieve, however, is to generate a long term structural need to decrease revenue or reimpose other taxes. As we can see the US Congress's inability to do either, it achieves a structural pressure generating future deficits.
If you want to pay down US government debt quickly, you would be far better of imposing a temporary Tobin tax, (or as a tobin tax is a good idea in any event, a temporary Tobin tax surcharge).
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scaddenp at 10:08 AM on 16 June 2016The Grand Oil Party: House Republicans denounce a carbon tax
"This means balancing the budget on average; i.e., surpluses during boom years and balanced budgets on average years."
Here in NZ, this is called the Fiscal Responsibility Act 1994
I think a lot of nations should try it. *smug*. Cant help myself.
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CSM at 09:31 AM on 16 June 2016The Grand Oil Party: House Republicans denounce a carbon tax
@Tom Curtis: I respectfully disagree. We have 19 TRILLION dollars in debt and the Baby Boomers are starting to retire! If a carbon tax produces a temporary surge in revenue, so be it. We need some temporary surpluses to offset 80+ years of crises. I would use some of the revenues as a citizen dividend just to keep a carbon tax from being too regressive.
And for the record I am a smaller government guy. I usually vote Libertarian. But I do believe in paying for the government we have, and the government we had. Even with a half trillion dollar cut in annual spending, we still could use some tax increases.
General environmental note: if you desire a future where progress means more leisure vs. more environmentally degrading stuff, you want an economy that doesn't require ongoing artificial stimulus. This means balancing the budget on average; i.e., surpluses during boom years and balanced budgets on average years.
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Tom Curtis at 09:07 AM on 16 June 2016The Grand Oil Party: House Republicans denounce a carbon tax
knaugle @14, IMO the opposite is the case.
Carbon taxes should be imposed on the fee and dividend basis because, by their nature, they are intended to dry up over time. Ideally, within 34 years, a carbon tax will provide zero revenue to government because we will have zero net emissions. If the carbon tax is not distributed back to the populace on a fee and dividend basis, that means the service it funds will have had its revenue dry up. In a worst case scenario, the tax will have been used to widely replace income and/or sales taxes which would then of necessity need to be reimposed gradually over time to replace the diminishing return from the carbon tax, with the consequent political battles to do so, both in elections and in the legislature. The most likely outcome would be a dimishment of general revenue, and hence of government services.
Ergo, to keep government services well funded, carbon taxes should be revenue neutral on a fee and dividend basis, or at worst used for short term, non-ongoing measures that will accelerate ending carbon dependence in the economy. (Note that ongoing subsidies of renewables does not fall into this category, for the funding of such subsidies must be drawn from general revenue as the carbon tax dries up, again creating a potential budget crisis.)
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