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CBDunkerson at 01:34 AM on 3 December 2010Renewable Baseload Energy
BP, yes yes... moving the goalposts. First it is completely impossible. When pointed out that it already exists suddenly the story is that it is evil and dangerous. Which is nonsense too, but whatever. There are none so blind as those who will not see. -
Daniel Bailey at 01:16 AM on 3 December 2010Stratospheric Cooling and Tropospheric Warming
Re: Joe Blog (57) Cool. But I think it's a bit like in the field of medicine, where there exists a world of difference between clinical studies and clinical practice. For radiative physics, CO2 and the stratosphere, I like the way Spencer Weart said it in the RealClimate post Spaceman Spiff (51) linked to earlier:"As for the stratosphere above the level where the heat is radiated out, who cares? It’s a very thin gas that doesn’t contain much heat energy and is easily influenced by anything. The real heat energy that we need to worry about is in the lower atmosphere. (In fact, still more in the oceans, where most of the new heat energy is going over the decades. At present we’re not radiating out quite as much as we take in, so there’s heat energy building up in the system.)"
But I do understand the need to know. :) The Yooper -
Berényi Péter at 01:14 AM on 3 December 2010Renewable Baseload Energy
#282 CBDunkerson at 23:37 PM on 2 December, 2010 For example, please explain the existence of 'Solar Energy Generating Systems' (SEGS). The largest solar power facility in the world (currently, several larger are now being built). Online for more than 20 years now. Built and operated without 'massive' government subsidies. Has been producing reliable baseload power for about a quarter of a million homes in southern California at competitive prices and making a profit since day one. I see. You mean the one where 4300 m3 "mildly toxic" coolant (called Therminol) exploded on February 26, 1999 (it was dismantled last year). Very safe, very green, very environmentally friendly.As for profitability, Federal and state investment tax credits, solar property tax exclusion & accelerated depreciation surely helped a lot. It is public money of course, payed for by American taxpayers. There's nothing sweeter under the Sun than money collected by IRS and going directly to private pockets, especially if you are not required to pay for damages in case of industrial accidents.
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CBDunkerson at 23:50 PM on 2 December 2010Renewable Baseload Energy
BTW, if 'never having been done' is "proof" that something can't be done... well then we can only conclude that commercial Thorium/IFR reactors are not feasible. After all, unlike commercial renewable energy projects those really haven't ever been done. -
CBDunkerson at 23:37 PM on 2 December 2010Renewable Baseload Energy
Peter Lang #272: "If you add wind power and solar power and biomass and geothermal and wave power and any more you want to add you raise the cost but still do not get the power reliability that society demands. The proof of this is that it has never been done" Which is simply untrue. For example, please explain the existence of 'Solar Energy Generating Systems' (SEGS). The largest solar power facility in the world (currently, several larger are now being built). Online for more than 20 years now. Built and operated without 'massive' government subsidies. Has been producing reliable baseload power for about a quarter of a million homes in southern California at competitive prices and making a profit since day one. Granted, SEGS is 30 year old technology so it relies on natural gas backup... for just 10% of the total energy produced. Your claims are provably false. -
Paul D at 23:36 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
Joe Blog: "So what some of us are contending, is that above the troposphere, CO2 is a net emitter, due to the pressure." I think it is obviously a combination of things. Reduced Pressure: photons have a lower probability of colliding with other molecules. Also fewer collisions between molecules. Closer to space and a thinner atmosphere: Assuming a photon missed hitting another molecule, it also has a better chance of escaping away completely into a 'vacuum'. It's all down to probabilities. -
CBDunkerson at 23:28 PM on 2 December 20102nd law of thermodynamics contradicts greenhouse theory
Tom Dayton #257: "Energy transferred by radiation down, warms the atmosphere below." damorbel #263: "Only if it exceeds the photon energy coming up." Nonsense. There is just no logical way to arrive at that conclusion. You aren't just spouting ridiculous violations of basic physics, but also basic math. Let's say the "photon energy coming up" is 5 units per time X and the energy going down is only 1 unit per time X. The down photons are less than the up photons so you claim they cannot result in a warmer surface. Put the starting energy at the surface at 100 units. Ignoring incoming energy for simplicity, after 1 X has elapsed this would yield; 100 - 5 + 1 = 96 You claim this is no warmer than; 100 - 5 = 95 Which is just wrong. 96 > 95 Adding an extra step for incoming energy would obviously yield the same result. The surface is warmer with the down photons than without them. Early grade school level mathematics. Inescapably true. Yet you deny it. That's just pathetic. -
Rob Painting at 23:20 PM on 2 December 2010Renewable Baseload Energy
Peter Lang - is this you (comment at 5.25pm 2nd Dec 2010) over at Brave New Climate?. The effect of cutting CO2 emissions to zero by 2050 -
damorbel at 23:10 PM on 2 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #257 Tom Dayton you wrote:- "So "adjacent" molecules include the ones below. Energy transferred by radiation down, warms the atmosphere below." Only if it exceeds the photon energy coming up. This should be obvious from the formation of the stratosphere where the energy absorbed by O2 & O3 warms the atmosphere with characteristic results, there is a consequent temperature inversion (the temperature rises in the stratosphere from about -50C to about 0C, depending on where you look) and suppression of convection. This stratospheric warming phenomenon when compared with the tropospheric lapse rate should make it very clear that the role played by absorption/emission via GHGs in the tropospheric temperature profile is non existent. -
Camburn at 22:42 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
What this model is trying to emulate is the atmosphere of Mars without pressure compensation. -
damorbel at 22:35 PM on 2 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #254 adelady you wrote:- " Your argument about insulating heat being "in" the container already is irrelevant." Not in reality. Read what Dr. Spencer puts in his OP:- "Imagine a heated plate in a cooled vacuum chamber, as in the first illustration, below. These chambers are used to test instruments and satellites that will be flown in space. Let’s heat the plate continuously with electricity" Dr. Spencer's model of a vacuum chamber makes nothing clear. I am familiar with the working of the type of chamber he shows. He shows an electric heat source, said to be at 160°F. How so? Lets say it is regulated but is its temperature uniform? Parts are much closer to the 0°F walls. The walls must be regulated to be a uniform 0°F over the inside surface (this is frequently done with liquid N2 but of course at −321 °F) Even if the heater is a perfectly uniform 160°F the temperature of the additional bar will only be uniform if it is a perfect (thermal) conductor, otherwise there will be a thermal gradient in it, a thermal gradient that depends greatly on the geometry of the entire installation. So is the 160°F source regulated? In which case the temperature is completely unaffected by the presence of the 2nd bar. In the case where the heater is a real heater i.e. it also has a geometrical thermal gradient, its temperature is not a uniform 160°F. But the nub of the matter is, what will change with the introduction of the brown bar? There are a number of scenarios:- 1/ Suppose the brown bar is a very good but not perfect coductor of heat and it is so big it touches the container wall and the heater so that heat has a fairly easy passage. The temperature between the heater and the bar now depends entirely where you measure it because it depends on the thermal conductivity of the materials of the heater and the bar. 2/ Let us now consider the case where the heater is a point and the bar also, so now conductivity has no role. This is a false proposition because a point has no surface area so it cannot, at 160°F or any other temperature, emit any energy. Lets ignore that and say there is a temperature gradient from a point at 160°F in the centre of Dr Spencer's container to the edge at 0°F. The temperature of the brown point in such an arrangement would depend on the position of the point and, since the point also has no surface area, it isn't affected by any emmission or absorption, just by the local photon intensity (the energy of the photons coming from the heater is not changed by the distance from the heater but the intensity i.e. photons per cm^2 is) falls according to the inverse square law. You will have noticed that there are many ifs and buts associated with my explanation but at least it tries to make something out of Dr. Spencer's quite unrealistic proposition. -
JMurphy at 21:55 PM on 2 December 2010Renewable Baseload Energy
A very informative article which is a breath of fresh air compared to some of the extreme pro-nuclear propaganda being posted here. As most of us agree, nuclear will take its place among a future supply which will eventually (sooner rather than later, hopefully) be dominated by renewables, because we need to ensure that renewables are the future - to get us away from dirty and dangerous carbon and nuclear. -
Peter Lang at 20:57 PM on 2 December 2010Renewable Baseload Energy
RSVP @275, Excellent post and so obvious too! -
Peter Lang at 20:53 PM on 2 December 2010Renewable Baseload Energy
swieder, It is you that should read the lead article. The opening paragraph poses the questions to be answerd on this thread: "A common argument against investing in renewable energy technology is that it cannot provide baseload power - that is, the ability to provide energy at all times on all days. This raises two questions - (i) are there renewable energy sources that can provide baseload power, and (ii) do we even need renewable baseload energy?" The answer to the question posed in the first sentence is NO!. Renewables (non hydro) cannot provide baseload power. Geothermal can in volcanic areas and biomass can but only small quantities. Geothermal and biomass are insignificant in the scheme of what is required. "(i) are there renewable energy sources that can provide baseload power" The answer is NO! if we exclude hydro which firstly is not approved by Greenies and secondly there is little viable capacity left to be developed, especially in Australia which is the location I am talking about. "(ii) do we even need renewable baseload energy?" Clearly the answer is that we Do need baseload generation. Since it cannot be provided by non hydro renewables it needs to be provided by something else - either fossil fules or unprintable. This is clearly explainded in the article "the case for baseload" posted @ #271. You have your answers. I look forward to your acceptance of them (or further loss of credibility and further demonstration of lack of capacity for objective analysis) -
RSVP at 20:53 PM on 2 December 2010Renewable Baseload Energy
archiesteel #183 @RSVP: "As to what other posters have said, and no lack of sincerity, it is precisely the great energy associated with fossil fuels that led to the population explosion in the first place." I'm sure you can provide scientific evidence that the two are directly correlated? I'm intrigued by this idea, because the countries that have had the biggest population increases are far from being the ones with the most gas-powered vehicles per capita. I'll be waiting for that..." Sorry to keep you waiting. It's a long story, and can be told many ways. It should be pretty obvious that unless a household, farm, or small village is able to survive on local subsistence, there are very real dependencies on transport. Transport to export, and inport goods. For instance, you just might need some rebarb, cement, bricks etc. for building as your population expands. Some places dont do too well living in tents. While not impossible, modern conveniences such as having a roof over your head provide free time for other ways of being productive, and have in so doing sustained expansion. (And by the way, that heavy metal normally comes from some far off fossile fuel driven foundry). Fossil fuels have facilitated growth regardless of whether the majority of a population owned its own motor vehicle or not. Ironically, after laying down rail, and opening and paving roads to make places more accessible, in many cases those same roads have served to ultimately de-populate many rural areas, as less hands have been needed on farms due to mechanized farming, (run by fossil fuels). As far as providing correlative evidence, simply consider the world population before the Industrial Revolution. Modern science tells us we've been homo sapiens for a few million years now. Plot fossil fuel consumption and population vs time, and see how it doesnt resemble the kinds of hockey stick graphs touted on this website making a case for correlation between CO2 and temperature. This one goes back two million years, not just two thousand. And by the way, the problem is not in the excesses of those water skiing off their yachts, but the ever so tenuous link for those whose meal unfortunately depend on the arrival of a container vessel somewhere, which in turn depends on the price of a barrel of oil. Most unfortunately, this includes about 99 percent of the human race. -
damorbel at 20:24 PM on 2 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #253 Riccardo you wrote:- " part of the spectrum. " Your argument is that something can be 'black' in part of the spectrum. No it can't. On that basis a bright yellow surface can be called 'black' because it has nothing in the blue part of the spectrum, green has nothing in the red or blue part of the spectrum. When doing thermal and energy calculations black must mean 100% of the spectrum or you will get a false answer. A black body absorbs 100% of the spectrum by definition. A black body (above 0K) emits (with different intensity) in 100% of the spectrum, by definition. 'Real' black bodies fall short of this 100% property for each of two possible reasons, they reflect like Earth or a mirror thus never quite 100%, or they transmit like glass or CO2 but never quite 100%. Glass is particularly interesting because it is obvious the reflection is where the refractive index changes. All materials, even gases, have a refractive index >1, consequently no material substance can behave according to the definition of a black body. -
swieder at 19:56 PM on 2 December 2010Renewable Baseload Energy
@Peter Lang "The proof of this [renewable baseload] is that it has never been done" I am not willing to accept this as an argument for this discussion, yet your insisting is entirely based on this. This attitude would have kept human mankind in stone-age or even in an earlier stage. And please apply it also to "your" solution of the 4th generation nuclear reactors and fusion. Much more important, though: this thread is not about "have renewable already demonstrated baseload capability?", would you please finally accept that? Maybe carefully read the intro article on top of this thread by dana1981. -
Peter Lang at 19:37 PM on 2 December 2010Renewable Baseload Energy
actually thoughtful, Quokka posted the EIA's projected levelised costs of electricity generation for the USA. However, you also need to read the assumptions. You cannot (should not) compare the costs of solar and wind power with the cost of baseload power. They are not comparable. Solar and wind do not provide baseload power. The costs provided are for wind power that is supplied when the wind blows (whether wanted or not) and for solar power that is supplied when the sun shines (wanted or not. The wind and solar energy have low value - almost valueless to the electricity industry. They are intermittent and cannot be dispatched on demand (mostly). They are a nuisance. They would not be built if not for the subsidies and government regulations that mandate their power be purchased. -
Peter Lang at 19:25 PM on 2 December 2010Renewable Baseload Energy
Swieder, I agree with you the discussion is fruitless and tedious. But the reason is that you are tied to a belief that renewables must be able to provide baseload power because you want them to, because ... well you just want them to. "Firstly, you constantly ignore all the hints given in this thread where mutliple times it was explained to you that none of the renewable as individual source or as individual generator is intended or ment to provide baseload power." Clearly you are not listening or not reading. I have addressed this - over and over again. I'll explain it simply for you. If you add wind power and solar power and biomass and geothermal and wave power and any more you want to add you raise the cost but still do not get the power reliability that society demands. The proof of this is that it has never been done despite the mantra you are repeating having been repeated over an over again for over 40 years. (except in unusual places like Iceland which sits on the Mid Atlantic Ridge and Norway with huge hydro potential). Work it out for yourself. If you assume $3,000/kW for each of these technologies (that is being generous because that is the cost of land-based wind power in Australia now and most of the others are far more expensive) then the cost of the five I mentioned is $15,000/kW. Add $1,000/kW for transmission for each and the total is $20,000/kW. But still you don't have a reliable power suppy, so you need to add the cost of fossil fuel back up (assume gas at $1,000/kW). So we are up to $21,000/kW to do what gas alone could do for $1,000/kW. However, in most places it is cheaper over all to do it with you know what rather than gas. Is any of this getting through to you? -
Peter Lang at 19:08 PM on 2 December 2010Renewable Baseload Energy
actually thoughtful, here it is again: “The case for baseload” . Pity you didn't read it any of the times Quokka and I posted it previously at least three times so far). Perhaps you (and others who still don’t understand what baseload means) will read it and try to understand it this time. Is it any wonder my tone is not to yours and other liking. “The case for baseload” -
VeryTallGuy at 19:06 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
This is a topic which I've never been able to understand to my own satisfaction. Let me test if I've got this right. 1) The stratosphere features very little convection, so radiative heat transfer dominates 2) The stratosphere is heated by UV absorption by ozone and also somewhat by IR absorption by CO2. 3) Due to higher CO2 levels, more IR is absorbed in the troposphere, so less in the stratosphere, resulting in cooling of the stratosphere as CO2 rises. Is this correct ? It begs one question, which I think needs a full heat transfer model to answer: Consider a thought experiment with CO2 at zero. There is no CO2 IR absorption either in the troposphere or stratosphere. Now allow CO2 to rise. Initially, despite increased (from zero) tropospheric CO2 IR absorption, there will also be increased stratsopheric absorption (by definition, as it was zero) So we initially expect a rise in stratospheric temperature, peaking at some level of CO2, then falling as increased tropospheric absorption blocks stratospheric IR absorption by CO2. Is this correct ? And if so what's the CO2 level at which stratospheric temperatures start to fall ? -
Gareth at 18:50 PM on 2 December 2010The Climate Show #3: Cancun and cooling
The URL is a dead giveaway... ;-) -
Joe Blog at 18:47 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
Daniel Bailey Its really more a question of optical depth for a given wavelength, the probability of it absorbing vrs emitting. Which is basically due to the number of molecules in a given area. If a molecule absorbs more than it emits, it increase its energy. If it emits more than it absorbs, it decrease its energy. So the further apart the molecules are, the greater the probability a given photon will travel further before it is absorbed. Its decreasing the probability of absorption vrs distance... Now if the atmosphere is opaque to say UV, but transparent to 15 micron... the UV will heat the other gases(well O3, and the O3 will heat the other gases) through absorption, and collisional energy transfer, but the probability is that energy that is lost by a molecule(O3) through emitting is replaced by absorption of radiation from a neighboring molecule. However, the heating of the other gases by the excited O3 will also heat CO2, causing it to emit, but if the probability is greater for it to emit more than it absorbs, just due to the distance a photon can travel between emission and absorption, it will cause a net energy loss from a given area through radiation. So what some of us are contending, is that above the troposphere, CO2 is a net emitter, due to the pressure. -
quokka at 18:44 PM on 2 December 2010Renewable Baseload Energy
267 actually thoughtfull EIA distinguishes between PV and CSP on the summary page for 2016 cost projections. I have already posted this once before on this thread. 2016 Levelized Cost of New Generation Resources PV is assessed as the most expensive of all technologies. -
swieder at 18:11 PM on 2 December 2010Renewable Baseload Energy
@Peter Lang, #263 Your strategy here is twofold it looks to me: Firstly, you constantly ignore all the hints given in this thread where mutliple times it was explained to you that none of the renewable as individual source or as individual generator is intended or ment to provide baseload power (it is obvious that this is of course not the case, exception might be solar thermal plants if storage size is adequatly). But everybody else seem to understand that the fluctuations in time differ from geographic location to anther location and that thereby distributed sites across a country very well technically provide true baseload power if properly managed (as already demonstrated). And secondly, you constantly suggest that nobody other then you has a clue what baseload power is. I have not read any new statement/information from your side in your (at least) last 5 posts - and i said already: repeating the same thing over and over again does not add value to the information behind. I'd say this is fruitless and tedious. -
actually thoughtful at 17:41 PM on 2 December 2010Renewable Baseload Energy
Peter Lang, I personally would prefer you not post again until you provide your definition of baseload power. So far, reading your posts, I presume baseload power means "electricity generated from nuclear." Have I got that right? I didn't realize that two different sources would overwhelm you. -
actually thoughtful at 17:38 PM on 2 December 2010Renewable Baseload Energy
I checked the 2010 report - it shows wind cheaper than nuclear in 2020, and cheaper by a larger margin in 2035. http://www.eia.doe.gov/oiaf/aeo/pdf/0383(2010).pdf (report page 67, PDF page 76) Why do I say DOE/EIA is biased against renewables: 1) Because they are 2) No mention of concentrating solar power in the 2010 report 3) No mention of peak oil 4) Doesn't distinguish between solar PV and concentrating solar power 5) They underestimate cost reductions for renewables 6) They are structured to support old energy, not new energy. 7) Climate change is mentioned 2 (two) times in the "Annual Energy Outlook 2010" Proof - watch how renewables do in reality compared to the 2010 outlook. -
Peter Lang at 17:18 PM on 2 December 2010Renewable Baseload Energy
actually thoughtfull, You are mixing so many different figures this is simply nonsense. You mix 2006 costs with current costs and mix the cost of baseload and non baseload power. The post is totally irrelevant. For heavens sake are you simply ignoring everything you've been told about making proper comparisons? -
actually thoughtful at 17:03 PM on 2 December 2010Renewable Baseload Energy
KR, As you requested - here is DOE/EIA data showing the costs of various fuels: "The lifetime cost of new generating capacity in the United States was estimated in 2006 by the U.S. government: wind cost was estimated at $55.80 per MW·h, coal (cheap in the U.S.) at $53.10, natural gas at $52.50 and nuclear at $59.30. However, the "total overnight cost" for new nuclear was assumed to be $1,984 per kWe[38] — as seen above in Capital Costs, this figure is subject to debate, as much higher cost was found for recent projects." http://en.wikipedia.org/wiki/Economics_of_new_nuclear_power_plants#Cost_per_kW.C2.B7h [Note that the N(unprintable) figure seems to be 1/3 of reality for the United States] So what about Solar PV? http://www.renewableenergyworld.com/rea/blog/post/2010/06/solar-photovoltaics-pv-is-cost-competitive-now (I know the source looks biased - read the article and decide for yourself). OK, convert the .10-.40/kWh to per MW·h as above = kWhX1,000 = $100-$400 per MW h (note that these come from different sources - so it looks like apples-to-apples but it might be crab apples-to-granny smith apples. -
Spaceman Spiff at 16:44 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
I've just recently bought the 3rd edition of John Houghton's textbook, "The Physics of Atmospheres". I've done some perusing (which is nowhere near enough) and found that my suggestion in the first paragraph of comment #33 regarding the possible state of LTE (or non-LTE) in the stratosphere wrt the 15 micron band transitions is incorrect. For these transitions LTE is still a good approximation up to an altitude of at least ~70 km. However, the second paragraph of the same comment (#33) appears to be on firm (if somewhat muddy) ground. In section 4.8 of Houghton's book, "Cooling by carbon dioxide emission from upper stratosphere and lower mesosphere", it mentions that for these atmospheric levels: 1) the temperature distribution is mainly determined by a balance between radiative cooling in the IR from CO2 and heating by photo-absorption of O3 by incoming solar radiation. 2) an approximation known as "the cooling to space" approximation may be employed, "in which the exchange of radiation between layers is neglected in comparison with the loss of radiation direct to space". To me, this latter comment seems to imply that the stratosphere is largely optically thin to CO2's main IR band centered near 15 microns. Adding to Tom Curtis' post (#55), the stratosphere is definitely in radiative equilibrium, so your findings from Archer's radiative equilibrium model ought to be reasonable. -
Tom Dayton at 16:36 PM on 2 December 20102nd law of thermodynamics contradicts greenhouse theory
damorbel, you wrote "Since emitting (GH) gases absorb also there is no chance that any imbalance in thermal energy transfer will arise as described by 'back radiation.'" You are wrong. Greenhouse gases do not absorb 100% of the radiation they emit; they do not create a closed cycle that traps the energy within the greenhouse gases. They emit radiation in all directions, including down. If other greenhouse gas molecules in that downward direction absorb that radiation, those molecules in turn radiate in all directions including down. That downward cascade of radiation continues all the way to the bottom of the atmosphere, where due to the closeness of the surface, a substantial amount of the downward radiation avoids reabsorption by other greenhouse gases and so makes it to the surface. Also, greenhouse gas molecules transfer the energy they acquire not just by radiation but also by conduction. As KR explained on another thread, a CO2 molecule on average has 1000 collisions with other molecules in which it transfers energy, before it emits a photon. Those collisions are with not just other greenhouse gas molecules, but with any molecules--non-greenhouse gas molecules, liquid molecules, solid molecules. The recipients of those energy transfer in turn collide with other molecules of all kinds, thereby transferring the energy again. Thus collision (conduction) is an additional path for greenhouse gases causing warming. -
Tom Curtis at 15:50 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
For what it is worth, I ran the Modtran model at Archer's website with the following values: CH4 = 0; tropospheric ozone = 0; stratosperic ozone scale = 1; Ground T offset = 0; Hold water vapor = pressure; Water Vapor Scale = 0; Tropical Atmosphere; and No clouds or rain. I then set an altituded of 18 km (the tropopause) and compared Iout for both 100ppm and 1000 ppm CO2, both looking up and looking down. By looking down, we measure the effect of changes in outgoing radiation, and hence of IR radiation in the CO2 absorption band entering the stratosphere. The effect was to reduce the outgoing IR radiation by 18 watts/meter^2. By looking up, we measure the change in IR radiation emitted by the stratosphere. The amount emitted downwards changed by 4 watts/meter^2, so the total change (both radiation directed to the surface and to space) would have been 8 watts/meter^2. None of these figures represent an equilibrium responce, as surface temperature is held constant in the model. As the atmosphere approaches equilibrium, the decrease in outgoing radiation from the troposphere would reduce as the surface warmed; and the difference outgoing radiation sourced from the stratosphere would also reduce as the stratosphere cooled. Further, it is not possible to simply compare the two values and say that because one is larger than the other it has a dominant effect. The decrease in IR warming of the stratosphere would be a function of the wave length specific emissivity times the reduction in incoming IR radiation, and the emissivity would be less than 1. Testing that later point, I checked Iout for 70 km, looking down. There was around 14 watts/meter^2 difference in the two cases. That suggests very little of the outgoing IR radiation from the troposphere is absorbed in the stratosphere, which in turn suggests improved efficiency in cooling the stratosphere with increased CO2 is the dominant effect. To the extent that we can trust this model for this (which is to say, not very far), that would indicate that: Both effects are active, and relevant for cooling; and Improved efficiency of cooling is the more important of the two effects. Having said that, Gavin certainly appears to prefer the theory that stratospheric cooling is predominantly because of reduced IR radiation from the troposphere. I would certainly appreciate if he were to have another attempt at explaining the effect. -
Spaceman Spiff at 15:14 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
Knutti & Hegerl (2008): The equilibrium sensitivity of the Earth's temperature to radiation chanages -- the most relevant of which is Figure 1. However, not much ink is expended in explaining the change in the stratospheric temperature profile. It's based on similar plots appearing in several of Hansen's papers. -
Daniel Bailey at 15:01 PM on 2 December 20102nd law of thermodynamics contradicts greenhouse theory
FWIW, posted some molecular visualizations of the various states of the CO2 molecule here. The Yooper -
Daniel Bailey at 14:56 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
Managed to pull out those molecular visualizations of CO2 from the GIF's (from Timothy Chase's website): Ground State Mode********************************************************************************* Pure Symmetric Stretching Mode The pure symmetric stretching mode v1 of CO2. While this is a mode that may gain and lose energy collisionally it is not infrared (IR) active as there is no transient electric dipole.
********************************************************************************* Bending Mode V2 The bending mode v2 of CO2, responsible for the 15.00 μm (wavenumber 667 cm-1) band -- the mode dominating the enhanced greenhouse effect and that primarily used by AIRS. This is infrared (IR) active due to a transient dipole: bending results in charge being asymmetrically distributed with net positive near the carbon atom and negative near the two oxygen atoms.
And
********************************************************************************* And Asymmetic Stretching Mode V3 The asymmetric stretching mode v3 of CO2 is responsible for the 4.26 μm (wavenumber of 2349 cm-1) band. The asymmetic stretch result in a net positive charge near the carbon atom and a net negative charge with the isolated oxygen atom, creating an electric dipole and making it infrared (IR) active. Given the range of atmospheric temperatures and concentrations of CO2 the bending mode v2 plays a greater role in climate change.
********************************************************************************* Now the hard part: understanding it...(if I've mis-attributed any of these, let me know) The Yooper
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Tom Dayton at 14:53 PM on 2 December 20102nd law of thermodynamics contradicts greenhouse theory
damorbel, you wrote "Heat transfer due to radiation goes only in one direction only, out into deep space." Yes, but the energy (via radiation) transfer in the direction down to the surface reduces the heat (net transfer of energy) from the surface up toward space. Which means that activity by greenhouse gases slows the cooling of the surface. Without greenhouse gases providing that offsetting (dare I say "back"?) radiation toward the surface, the heat (net transfer of energy) from the surface up would be larger, so the surface would cool faster, outstripping the replenishment of energy from the Sun, and consequently the surface would end up colder. -
Spaceman Spiff at 14:44 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
fyi: the author of comment #17 in the RealClimate link noted above, is Andy Lacis, who is a colleague of Gavin's. -
Tom Dayton at 14:41 PM on 2 December 20102nd law of thermodynamics contradicts greenhouse theory
damorbel, you wrote:Even higher up in the atmosphere the gas density becomes so low and the chance of a photon being reabsorbed becomes correspondingly low. For thin atmospheres many photons emitted by H2O & CO2 do not get reabsorbed by adjacent H2O & CO2 molecules, some are reabsorbed by the surface but others are absorbed by deep space.
I'm not sure you are thinking three dimensionally. Even way high up in thin atmosphere, H2O and CO2 molecules are emitting radiation in all directions, including down. So "adjacent" molecules include the ones below. Energy transferred by radiation down, warms the atmosphere below. That layer of atmosphere also radiates in all directions, including down, thereby warming the atmosphere below it. That cascade continues down to the surface. -
Spaceman Spiff at 14:34 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
Sphaerica @47 et al. Have a look at commments #17 and #19 in the RealClimate link mentioned by Andy S (@35): Why does the stratosphere cool when the troposphere warms?" -
muoncounter at 13:42 PM on 2 December 2010A basic overview of Antarctic ice
#84, #85: HR, you objected to V09's use of a few years of data to generate a trend. Yet you use a self-described 'blip', one year long, to conclude that no 'strong assertions' can be made. "It really all does hinge on the anomalous 2006 data". How is what you are saying any better than what you say Velicogna has done? I merely drew an analogy to the 1998 'blip' of high temperatures, alluding to those who claim that one year will determine that 'it hasn't warmed' -- until that one year's temperature is exceeded. (And then the goal posts will be moved again, but that's a separate story). "and the fact the author choose to start and end her trends on that year." Read the portions I quoted in #73. It doesn't appear arbitrary: We fitted two straight continuous lines through the data, i.e., connected in the middle. We find that the Radj^2 for the two lines regression model is 0.97, the same than for the quadratic model I grant that your points about rebound velocities in #85 are legit and maybe the GRACE estimates are high. However, any rebound in Antarctica is not truly post-glacial in the sense of PGR from the Wisconsin ice sheet, as the ice in Antarctica is still there. If there is rebound in Antarctica, there must in fact be ice loss, because ice loss is what causes rebound. Searching 'antarctic ice loss' in Google Scholar, I find studies documenting measurements made by a wide range of technologies other than gravitational satellite: radar interferometry, shelf glacier acceleration, calving, rapid proliferation of crevasse systems and meltwater ponds, etc. None of these features are consistent with ice gain. -
Daniel Bailey at 13:21 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
You guys have left me behind on a subject I thought I've kind of understood... ...so you made me start looking around. Fortunately, the Rabett has a timely post on the subject that may hopefully shed some light on the issue. Or obscure it (you tell me). Also ran across this video linked by Timothy Chase (from his discussion of his avatar page - TIP: has some neat GIFs of the energy states of CO2). HTH, The Yooper -
Joe Blog at 13:00 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
Sphaerica at 11:51 AM I would interpret the tropopause as a result of pressure/transparency(in LW), reaching a level where the balance of energy is lost..ie its no longer effectivly opaque to the passing of terrestrial LW, more energy is lost from here than what is received both above and below it from SW and LW absorption. So adding more co2, should increase opacity vrs altitude, raising the level of the tropopause, simply put, because there are more opaque molecules in a given area than prior to the rise. But the change in incoming and out going energy, is only going to be small, it will require a rise in T at all levels below the tropopause to enable the transport of energy up, but the difference in quantity of LW emitted will be inside the margin of error for measurements at the now, but an accumulation of energy should occur. Its lengthening the path length for the escape of energy, not stopping it until it reaches an overflow point. But the tropopause, marks the altitude, where the atmosphere is no longer effectively opaque to the passing of LW. -
Peter Lang at 12:45 PM on 2 December 2010Renewable Baseload Energy
scaddenp, Regarding "economically" people are already getting annoyed about the increasing costs of electricity and we are talking about 30% so far. If we went with renewables the cost of electricity would increase by a factor of 5 to 10 and we'd still have to maintain the fossil fuel plants because renewables cannot supply reliable power. There is no way people are going to accept their electricity prices (and all the other flow on costs) increase that much, especially when there is a much lower cost (and more environmentally benign) way odf supplying our electricity. Nuclear is banned in Australia. Even if the bans were removed it is likely that most of the impediments to nuclear would not be removed. The impediments would make N more costly than coal in Australia unless the impediments are removed. The impediments are a result of the western democracies' way of allowing public opinion and anti nuclear fears to override good policy. That is why the estimated cost of new nuclear nuclear power station in USA, Canada, UK etc is up to 4 times more costly than in China (cost of local labour is a small component of the cost). The sort of impediments and regulatory distortions to the market that are blocking nuclear in Australia are: 1. ban on nuclear power 2. high investor risk premium because of the politics 3. Renewable Energy Targets 4. Renewable Energy Certificates 5. Feed in Tariffs for renewables 6. Subsidies and tax advantages for renewable energy 7. Subsidies and tax advantages for fossil fuel electricity generators 8. subsidies for transmission and grid enhancements to support renewable energy 9. massive funding for research into renewable energy 10. massive subsidies for research into carbon capture and sequestration (CCS) 11. Guarantees that the government will carry the risk for any leakage from CCS 12. No equivalent guarantee for management of once used nuclear fuel 13. Massive subsidies and government facilitation for the gas industry, coal seam gas and coal to gas industries (despite the latter putting toxic chemicals into the ground water and the Great Artesian Basin water) 14. Fast tracking of the approvals process for wind power, solar power, gas industry, coal industry while nuclear industry remains band from even fair comparative studies by Treasury, Productivity Commission, ABARE, Department of Climate change and more. We can just imagine what the approvals process would be like for a nuclear power plant!! -
Peter Lang at 12:30 PM on 2 December 2010Renewable Baseload Energy
Rob Honeycutt, @261, I don't understand why you don't understand that wind power cannot supply to meet basle load. Do you understand what baseload means? I am convoinced you don't. Until you do, there is no point in you posting here. Your comments are off topic because they are not about basload. Wind power could only generate to meet basload if it had enormous amounts of storage - like 50 days at full power. I've explained this previously. The costs of any storage to try to make wind power baseload are totaly uneconomic - too high by orders of magnitude. -
scaddenp at 12:13 PM on 2 December 2010Renewable Baseload Energy
Peter - thanks, I make mistakes too and much more likely to take an interest in the opinion of people who admit it. As to "economically" - well what people pay for energy is something of a choice. If you have a people that say no to nuclear for various reason and no to fossil for various reasons, and so are prepared to pay a massive hike for energy, then sure its economic. I wouldnt, but then I live in a place with base-load hydro and geothermal and no subsidies. If you wanted to build nuclear, then you would have to raise the financial interest and apply for resource consent (which i would imagine to be a very involved process). The arguments about safety would wash out in the consent hearing and the economics in the raising of the capital. What's stopping someone doing this in Australia? -
Rob Honeycutt at 12:09 PM on 2 December 2010Renewable Baseload Energy
Peter... Once again, "does not" is not the issue at hand. Whether it can and whether it will is another matter. China IS at the crux of the issue you seem to want to avoid because they are on track to do exactly what you say can not be done. Is it your position that China is on track to do something that will ultimately fail? -
Bob Guercio at 12:05 PM on 2 December 2010Stratospheric Cooling and Tropospheric Warming
Sphaerica - 47 I've actually emailed Gavin asking him to take a look at this blog. All I could do is hope that he responds. I'll keep you guys posted. Bob -
Peter Lang at 12:04 PM on 2 December 2010Renewable Baseload Energy
Rob Honeycutt, Why do you keep on talking about the capacity of wind in China. This discussion is about baseload renewables. Wind does not and cannot supply base power. -
Peter Lang at 12:00 PM on 2 December 2010Renewable Baseload Energy
scaddenp, "Peter Lang's argument seems to me that he think nuclear and fossil are the only ones capable of providing base-load power NOW and that they do this much cheaper than any future renewable (non-hydro, non-geothermal) means. This is not exactly the same as "can renewables provide base-load energy" (for a given definition of "base-load"). " That is a fair summary. But I need to clarify. I say "non-hydro renewables cannot provide significant quantities of baseload generation NOW, and probably will never be able to economically." If you leave out the "economically" the whole discussion becomes an irrelevant, theoretical exercise. -
Rob Honeycutt at 11:59 AM on 2 December 2010Renewable Baseload Energy
quokka... Just found the 112 GW figure in another China Daily article.
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