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protestant at 09:24 AM on 21 March 2011It cooled mid-century
And try comparing vs something else than GISS which is showing less cooling in mid 1900's and also less warming pre 1940. Like Hadcrut which has not been so heavily adjusted by the modelers. For example, look at the Model E outputs. Aerosols clearly do not explain the mid century cooling. GISS vs ModelE vs Hadcrut: http://i.picasion.com/pic38/0f6666b2060569d680da06c477670f9b.gif -
ranyl at 09:19 AM on 21 March 2011Zero Carbon Australia: We can do it
"CBDunkerson at 04:30 AM on 21 March, 2011 ranyl #46, keep in mind that the current CO2 level is 'artificially inflated' in the sense that it represents an overflow rather than equilibrium value. Basically, about half the CO2 we emit each year is currently being sequestered (mostly in the oceans). If we were to drop to zero emissions that sequestration would continue and the atmospheric concentration would start dropping... probably at a rate of about 2 ppm per year. Thus, even if we hit 450 ppm before zero emissions goes into effect, we would not stay at that level once emissions stopped. As to 2C vs 3-5C... the difference is between fast feedbacks and slow feedbacks. A doubling of CO2 (about 560 ppm) will likely cause about 3C warming from fast feedbacks (i.e. within a few decades), but more likely around 6C when slow feedbacks (i.e. within a couple of centuries) are considered. However, both of those would require that the atmospheric CO2 level remain elevated... which it would not if our emissions drop significantly below the rate at which atmospheric CO2 can be sequestered." Yet others have found on the subject of the removal of CO2 from the atmosphere that, “not only does anthropogenic CO2 in the atmosphere need to be removed, but anthropogenic CO2 stored in the ocean and land needs to be removed as well....meaning an additional amount of CO2 equal to the original CO2 captured would need to be removed” Long Cao and Ken Caldeira Env. Res. Lett, 5 (2010) 024011 (6pp) http://iopscience.iop.org/1748-9326/5/2/024011?fromSearchPage=true Dunford (Science May 2007), showed southern Ocean sink now releasing CO2. (Park Geo.Res.Lett. 2008), showed 50% Reduction of sink of coast of Japan, (Schuster Oct 2007 J. of Geo. Res), Ocean sink 50% reduced N.Atlantic. Lowe (Env.Res.Let 2009,http://iopscience.iop.org/1748-9326/4/1/014012?fromSearchPage=true) , seems to suggest that CO2 levels even with adrupt stops take a long time to come and at a slow rate,"HadCM3LC simulates very low rates of decline in atmospheric CO2 concentration. Mean (regressed) rates of change for the following hundred years are predicted as –0.2 ppm y–1, –0.4 ppm y–1 and –0.75 ppm y–1," an order of magnitude lower that the 2ppm a year rate suggested, and not taking into account the release of CO2 from a warming atmosphere due to permafrost melt, the general relationship that a warming trend causes a release of CO2 nor CO2e which is already at 460ppm, so really getting to 350ppm is a lot of carbon removal. Do realise that the 3-5C is the long term equilibrium sensitivity equivalent and that in 100years you get about 60% of the full equilibrium level temperature change. That suggests that if the Pliocene CO2 levels were ~350ppm, then the earth should heat up 60% of the way to 3-5C by 2100, so 1.8-2.4C, if CO2 levels were ~400ppm in the Pliocene then the earth should rise at least 1C to 1.78ppm at 350ppm but 1.8-2.4C at 400ppm. There is enough uncertainity in this paleoclimatological records to create an endless debate, however considering the ever growing evidence for a higher CS than 3C and the risks involved of too much CO2 maybe 350ppm asap induced by a massive CO2 withdrawn due to man's activties is a pragmatic approach. What carbon peak is safe? (considering that unless CO2 is actively withdrawn it will stay at that level for a long time and CO2e levels) 400ppm means removing 50ppm and more from the atmosphere to get to 350ppm. That is a considerable amount of carbon so is there potential for bioshpere enhancement to draw down that much CO2? If 400ppm is a peak that leaves a very tight budget to replace a whole enery, transport, farming, health, economic and building systems (which are all fossil dependent) to being fossil independent and CO2 sequestering and there are also adaptation needs and the ever increasing population demands. Is such a large challenge of human adaptive ingenuity even worth considering? How quickly can human activity become carbon negative and biosphere enhancing with a best effort from all concerned parties? -
protestant at 09:19 AM on 21 March 2011Pre-1940 Warming Causes and Logic
And STILL not accounting for the oceanic interdecadal variability, which is a good explanation for the 1940 blip and for part of the 2000's blip as well and this is what the current climate models are not accounting for. The models you cite do not reproduce this blip, and it definitely is a problem. It is NOT just about external forcing You should already be aware of that. Also, using linear relationships for temperature changes (delta T = lambda x delta F) is a gross oversimplification because we KNOW climate is nonlinear (and so are feedbacks). Just because the models do reproduce the last 30 years with the supposed sensitivity combined with human factors doesn't mean they would "know" what actually has happened.
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Daniel Bailey at 09:06 AM on 21 March 2011Most of the last 10,000 years were warmer
Chris: Not all interglacials are created equal. Looking at the past 10,000 years showed an overall decline in temperature
until the age of industrialization, when the decline halted and temperatures began their climb
We have now equaled the highest temperatures of this interglacial (the period known as the Holocene Maximum or the Holocene Altithermal), with yet more warming in the pipeline; even if CO2 emissions are held to zero for the next 40 years, we're still going to be on the receiving end of another 0.6°C warming.
The Yooper
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andthorne at 09:06 AM on 21 March 2011Pre-1940 Warming Causes and Logic
Wrong Reindeer. In 1941, just below the Arctic circle in Canada the temperatures reached the level of a Palm Springs summer, 101 degrees, if I remember correctly and that summer temperatures which normal average 50 degrees were way higher, 70 degrees if I recall correctly. I am away from my research at the moment. The cause, I say, was a methane hydrate explotion below in the Arctic area that leaked the great heat the hydrates contain out of an Arctic pingo during the summer. They began drilling in the Arctic at Norman Wells in 1921; they began extensive water flooding in the late thirties while gearing up for WW II. Fresh water makes methane hydrate. It is methane emmissions we need to stop not CO 2. Andrea Silverthorne -
scaddenp at 08:58 AM on 21 March 2011Sea level rise is exaggerated
For a disastrous multi-meter sea level rise you'd need acceleration but you simply don't have it. What we would EXPECT is surely what models predict. Looking at say Vermeer 2009 I dont think we do expect to much acceleration yet. 2050 will be different. -
Berényi Péter at 08:31 AM on 21 March 2011One of the best climate change ads I've seen
#32 les at 08:15 AM on 21 March, 2011 I'm really curious. Here you go. -
Berényi Péter at 08:28 AM on 21 March 2011Sea level rise is exaggerated
#30 under One of the best climate change ads I've seen les at 07:47 AM on 21 March, 2011 I wasn't sure because the first data points on both are not the same as yours... That's because folks at University of Colorado at Boulders for some obscure reason have omitted the first three data points at the end of 1992 from the graphs, although it's included in the text files. If you give the comparative fit qualities, we can all judge whether a linear fit is not appropriate compared to your function... You miss the point. A linear fit is insufficient to raise alarm, it only implies a 27 cm rise by 2100 which is entirely manageable. For a disastrous multi-meter sea level rise you'd need acceleration but you simply don't have it. -
damorbel at 08:20 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
Re #612 Tom Curtis you wrote:- "3) The molecules in a gas do need to have significant kinetic energy to stay aloft. That is the energy of motion that they have because of the temperature of the gas. If the gas cools" You are so close to an important fact about atmospheres in general. You write "if tha gas cools" - as a molecule rises in the atmosphere it loses kinetic energy(KE) to gravitational potential energy (GPE). But the KE of a gas (well, degree of freedom, DOF; actually) is its temperature, so when it loses KE to GPE it must cool. This is so important because it establishes the basic lapse rate of 6.5C/km(altitude). -
cjshaker at 08:18 AM on 21 March 2011Most of the last 10,000 years were warmer
The temperature proxy record extracted from the Vostok ice cores appears to show the same thing, a peak about 10,000 year ago, and a gradual cooling trend since then. Look at the right side of this graph. The furthest right sawtooth is our current interglacial. It shows a temperature spike, then appears to show a gradual temperature decline. It also shows that this interglacial is colder than all of the previous interglacials over the past 420,000 years http://www.skepticalscience.com/argument.php?p=1&t=235&&a=53 Chris Shaker -
les at 08:16 AM on 21 March 2011One of the best climate change ads I've seen
I mean 17... -
les at 08:15 AM on 21 March 2011One of the best climate change ads I've seen
12 Berényi - please do repost 12 + the required analysis details in the sea rise post. I'm really curious. http://www.skepticalscience.com/sea-level-rise-intermediate.htm -
les at 07:47 AM on 21 March 2011One of the best climate change ads I've seen
29 Berényi Fine, I wasn't sure because the first data points on both are not the same as yours... still, both have a similar rate and precision... so my questions hold. What the huge discrepancy in rate? What do you mean by "very high confidence" for your decceleration? which you seem to be able to include with high precision and, I suppose, confidence. If you give the comparative fit qualities, we can all judge whether a linear fit is not appropriate compared to your function...
Moderator Response:[DB] OK, this has gone on quite enough. Anyone wishing to continue discussing sea level rise can carry this conversation over to the http://www.skepticalscience.com/sea-level-rise-intermediate.htm or similar thread of their choice. In a little bit I'm going to start removing all off-topic comments from this thread. Thanks!
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Berényi Péter at 07:35 AM on 21 March 2011One of the best climate change ads I've seen
#27 les at 07:20 AM on 21 March, 2011 I'm still curious about your fit It is actually this one (Inverted barometer applied, Seasonal signal included).
You can download numeric data from here. A linear fit is clearly not appropriate. But at least one can exclude any acceleration with very high confidence. Which contradicts Hansen's claim ("a disastrous multi-meter sea level rise on the century timescale").
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les at 07:32 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
707 RickG. I completely share your sentiments - although I hope not sufficiently as to violate the comments policy ;) There's been a lot of words attacking GHE... but no physics that I can discern. I'd suggest that those who feel there's a flaw in the GHE argument construct a clear, physics based, derivation - or find a flaw in explanations such as SoDs - until which time, IMHO, it's probably best to give it a rest. -
Paul D at 07:32 AM on 21 March 2011Zero Carbon Australia: We can do it
Interesting new development in vanadium redox flow batteries: http://www.sciencedaily.com/releases/2011/03/110317141418.htm -
les at 07:29 AM on 21 March 2011One of the best climate change ads I've seen
Moderators - and before you say it - I know, I know... should be in How much will sea levels rise in the 21st Century? -
RW1 at 07:26 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
Rick G, "Both of you take a perfectly legitimate and superbly illustrated schematic showing 'Earth's Global Energy Budget' and purposely misrepresent it out of context, completely ignoring the paper that describes it in detail." I've read the Trenberth 2009 paper, and yes, it misrepresents the most crucial aspect of the entire GHE. That is how much of the emitted surface radiation is from 'back radiation' from the atmosphere and how much is passing through unabsorbed and going straight out to space. The paper and diagram makes it look like of the 396 W/m^2 emitted at the surface, 333 W/m^2 of it is coming back from the atmosphere. This is incorrect. Using Trenberth's numbers, only 157 W/m^2 of surface emitted radiation is from 'back radiation'. The diagram also obscures what percentage of the surface emitted radiation absorbed and re-emitted by the atmosphere is downward emitted and what percentage is upwards emitted out to space. Using his numbers, 157 W/m^2 is downward emitted toward the surface and 169 W/m^2 is upward emitted, with 40 W/m^2 passing through the clear sky atmosphere and 30 W/m^2 passing through the cloudy sky atmosphere. The total transmittance of 70 W/m^2 is not referenced in the paper and seems to only be a rough estimate or guess. -
damorbel at 07:22 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
Re #705 RickG you wrote: "Your basic misconception concerning Trenberth's schematic appears to be about what the schematic is not about. It is not depicting the Stefan–Boltzmann Law and black body radiation." I suggest that you examine the document as closely as I have. All the power figures (W/m^2) e.g. 'Surface Radiation 390W/m^2' and 'Back Radiation 333W/m^2' appear to be derived by applying Stefan's formula (with an emissivity =1) to an estimate of the local temperature. Trenberth mentions 'real' temperatures (°C or K) only seven times and then only to explain how the figures were manipulated to make them more acceptable (see box on p315) The box also contains this unused information:- "The surface emissivity is not unity, except perhaps in snow and ice regions" which beggars belief. Snow certainly has a very low emissivity (and the corresponding low absorptivity) because that is why it takes a long time to melt as ground cover. It is only when the (absorptive) dark earth underneath begins to appear that radiation has a real effect melting the snow. You wrote further:- "The schematic is based on actual instrumental data showing how energy is distributed globally." I don't think you are right here. The only measurements that Trenberth uses are satellite measurments that even he admits are unreliable (because of instrument failure) and disagree violently e.g. compare the 'Solar reflected' (p316) for KT97(Trenberth) at 107W/m^2 and JRA(Japanese re-analysis) at 95.2W/m^2. Trenberth then goes on to use the difference of these measurements to calculate the extra heating due to radiation and the figure vary from positive to negative, depending on who is doing the measurements. Of course it isn't as simple as that; no, many of the figures used have all been re-analysed (aka - they didn't meet requirements) e.g. JRA aka Japanese re-analysis; NRA aka NCEP–NCAR re-analysis and ERA-40 aka 40-yr ECWMF Re-Analysis (p316). This kind of stuff reminds me strongly of [- snip -]Moderator Response: [muoncounter] Edited due to political accusations in violation of Comments Policy. -
les at 07:20 AM on 21 March 2011One of the best climate change ads I've seen
12 Berényi I'm still curious about your fit. You link to http://sealevel.colorado.edu/results.php I guess this data?
who show a rate of 3.1 ± 0.4 mm/ year, rather than your 18.8 cm / century 1.88 mm/year ... Why the discrepancy of 1.6? and how did you manage to get that extra significant figure of precision?!?!
Their rate is from a straight line fit. what function have you used?
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Henry justice at 07:15 AM on 21 March 2011Visual depictions of Sea Level Rise
The IPCC AR4 report projects a sea level rise for this century of 18-59 cm. While the edges of both Greenland's and Antarctica's ice caps have obviously melted a bit, this should balance out by the predicted increase in snow in the greater interior for both icecaps. It will take thousands of years of continuous warming for both of them to melt even at the present rate of emissions of CO2. By the way, these emissions are projected to peak by 2100 and then decline. There is no near term threat of unprecedented sea level rise.
Moderator Response:[DB] Umm, not so much. Greenland has been losing ice overall, with the rate of loss increasing each year:
With Antarctica losing ice in a similar fashion:
No one is saying that these great ice sheets will disappear overnight. But the negative effects on sea levels will become apparent far before then, causing great distress to coastal populations throughout the world.
"By the way, these emissions are projected to peak by 2100 and then decline."
Got a source for that? Because as it now stands, with no firm limits on global GHG emissions in sight it has about a snowflakes chance in...
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Rob Painting at 07:11 AM on 21 March 2011One of the best climate change ads I've seen
The distance is some four thousand kilometers and Greenland is losing ice in recent years at an annual rate of not more than 0.01%. It is negligible So you haven't bothered to do the math, or are unable to?. I'm not really interested in your opinion that it's negligible BP, I'd like to see if you have actually addressed this issue. If you don't know how to account for the effect, just say so. -
Berényi Péter at 07:00 AM on 21 March 2011One of the best climate change ads I've seen
#23 Rob Painting at 06:03 AM on 21 March, 2011 Have you calculated this?. Is it negligible for New York? Come on, get real. The distance is some four thousand kilometers and Greenland is losing ice in recent years at an annual rate of not more than 0.01%. It is negligible. BTW, anyone can visit the PSMSL (Permanent Service for Mean Sea Level) site. You are free to cherry pick a station which shows considerable acceleration during the last several decades provided it- does not sit on the side of a volcano
- there is no major tectonic fault line there
- it is not swampland
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RickG at 06:46 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
RW1 & damorbel, Well guys, there is no doubt that neither of you are the slightest bit interested in discussing any science with the intent of sharing information and understanding. Both of you take a perfectly legitimate and superbly illustrated schematic showing 'Earth's Global Energy Budget' and purposely misrepresent it out of context, completely ignoring the paper that describes it in detail. If you are still troubled with Trenberth's schematic and paper, I suggest you contact him personally. His email address, fax and phone number are listed prominently the NCAR site to which I have previously linked. As for me, I am through with your hand waving and obfuscation. -
Paul D at 06:15 AM on 21 March 2011Zero Carbon Australia: We can do it
idunno@49 It is common practice now to work out life cycle emissions as grammes of CO2 per kilowatt hour. These figures include materials used, manufacture, installation and decommissioning. Whether a fan or not, the world nuclear association has compiled quite a good list of research papers that analyse the CO2 footprints of different energy sources: http://www.world-nuclear.org/info/inf11.html Regarding wind turbines. The pad is largely concrete and then the tower is prefab steel bolted to it. On top of that is the nacelle/generator and blades. Tidal turbine farms are probably about 10 years behind wind in development, so the first small scale installations are just being planned/constructed. A 10 turbine farm has been approved this week in Scotland: http://www.independent.co.uk/environment/green-living/tides-to-power-whisky-distilleries-2245207.html -
les at 06:10 AM on 21 March 2011One of the best climate change ads I've seen
To validate this "decelerations" one would need to know the function fitted, the R^2, and the equivalent for a Log function and a straight line, at least. -
Rob Painting at 06:03 AM on 21 March 2011One of the best climate change ads I've seen
BP - Now, in New York rate of sea level rise is decelerating steadily during the last 85 years at about 0.3 m/cy2. During the last twenty years this deceleration, if anything, is more pronounced, not less so. Much of the contribution to sea level rise is now coming from the Greenland ice sheet. This would be expected to cause a reduction in sea level rise in areas adjacent to Greenland, and perhaps have an effect on SLR at New York, as the local gravitational attraction diminished. Have you calculated this?. Is it negligible for New York?. -
r.pauli at 05:39 AM on 21 March 2011Pre-1940 Warming Causes and Logic
In the decades after 1945 there were over 500 nuclear bombs exploded in atmospheric tests. Sometimes averaging 2 per week. All that stratospheric injection of dust and soot suggests a mini nuclear winter. -
Berényi Péter at 05:27 AM on 21 March 2011One of the best climate change ads I've seen
#19 Marcus at 23:11 PM on 20 March, 2011 BP @ #17-as if to prove my previous point, there you go with your Cherry Picking. Why 18 years BP? Unfortunately it happens to be the case we have global satellite altimetry only for the last 18 years. Before that time we have tide gauge data distributed unevenly along the coastlines and nowhere else. Do you really think it is cherry picking to use all the data available? However, we also have some pretty long datasets for various geologically stable environments like New York. Rate of sea level rise at individual spots does not have much to do with global ocean volume, as land itself has vertical motion depending on location. However, the acceleration term in the absence of major earthquakes or volcanism is telling, since rate of isostatic rebound is stable on millennial scale.
Now, in New York rate of sea level rise is decelerating steadily during the last 85 years at about 0.3 m/cy2. During the last twenty years this deceleration, if anything, is more pronounced, not less so.
Therefore any talk about accelerating sea level rise is rooted in fantasy, not facts.
Of course fantasy is a great resource for advertising, but for highways and countryside to actually get under water as claimed by your celebrated ad above a bit more is needed. Some considerable acceleration, that is. And sorry, it is not observed so far.
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RW1 at 04:53 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
damorbel (RE: 700), "Trenberth's diagram is deficient in so many ways it is beyond revision. The so-called 'back radiation' has the concept behind it that there is a place in the atmosphere from where 'back radiation' comes; but even John Tyndall knew that this is not the case. He measured both the emission and absorption by GHGs and found that their emitted radiation was completely absorbed by gases at a lower temperature." Yes, the Trenberth diagram is a confusing and misrepresents many things. What Trenberth refers to as 'back radiation' is really mostly downward emitted radiation - some of which last originated from the Sun, some of which last originated from the surface emitted, and some of which last originated from the kinetic energy (latent heat and thermals) moved from the surface into the atmosphere. As I was trying to explain earlier in this thread, the proper definition of 'back radiation' is the downward emitted radiation from the atmosphere that last originated from the surface emitted radiation. "This last means radiation emitted by GHGs is immediately absorbed and re-emitted by adjacent GHGs. This is so when the pressure and temperature gradient are zero; in the atmosphere the density reduces with altitude so the upwardly emitted radiation is not completely reabsorbed, an increasing %age gets ever higher until it escapes completely; that is the mechanism for heat radiation from the Earth." The key thing to note is that the 239 W/m^2 of post albedo energy entering becomes about 390 W/m^2 at the surface. The absorption and isotropic re-emission of the outgoing surface emitted infrared by GHGs and clouds is slows down the rate at which energy can leave, causing a 'back up' of energy at the surface. Essentially, what this means is it takes a 'back up' of 390 W/m^2 at the surface to allow 239 W/m^2 to leave the system, offsetting the 239 W/m^2 coming in from the Sun. -
dana1981 at 04:46 AM on 21 March 2011Zero Carbon Australia: We can do it
Ken #40 - the report suggests combining solar thermal with biomass burning. You can use much of the same infrastructure, and then you can still provide power during long periods without sunshine. -
Gilles at 04:42 AM on 21 March 2011Zero Carbon Australia: We can do it
MattJ#19 : In #3, I just gave some facts and asked some questions - so I don't know which "claims" you're talking of. Concerning Iceland, this is the most recent news I heard from "hydrogen economy" http://www.eenews.net/public/climatewire/2009/07/01/1 That's interesting, because my claim is that modern economies is possible only with cheap and convenient energy. So "alternatives" are not really interesting if they're neither cheap, nor convenient. A corollary is that when cheap and convenient energies (and despite their drawbacks, FF ARE cheap and convenient) will exhaust, economy will sink - and it just happened that some years after the peak of conventional oil , the barrel went up to the stratosphere, and western economy plunged into the deepest recession since the war -including Iceland, Denmark , and Spain, despite their high level of renewable electricity - which didn't help them at all to resist the economic tsunami. So for the moment, I just considering facts , and facts support my claims. -
CBDunkerson at 04:30 AM on 21 March 2011Zero Carbon Australia: We can do it
ranyl #46, keep in mind that the current CO2 level is 'artificially inflated' in the sense that it represents an overflow rather than equilibrium value. Basically, about half the CO2 we emit each year is currently being sequestered (mostly in the oceans). If we were to drop to zero emissions that sequestration would continue and the atmospheric concentration would start dropping... probably at a rate of about 2 ppm per year. Thus, even if we hit 450 ppm before zero emissions goes into effect, we would not stay at that level once emissions stopped. As to 2C vs 3-5C... the difference is between fast feedbacks and slow feedbacks. A doubling of CO2 (about 560 ppm) will likely cause about 3C warming from fast feedbacks (i.e. within a few decades), but more likely around 6C when slow feedbacks (i.e. within a couple of centuries) are considered. However, both of those would require that the atmospheric CO2 level remain elevated... which it would not if our emissions drop significantly below the rate at which atmospheric CO2 can be sequestered. -
RickG at 04:07 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
damorbel @ 703 Your basic misconception concerning Trenberth's schematic appears to be about what the schematic is not about. It is not depicting the Stefan–Boltzmann Law and black body radiation. The schematic is based on actual instrumental data showing how energy is distributed globally. Once again, please read the Trenberth et al paper. Earth's Global Energy Budget. -
idunno at 03:49 AM on 21 March 2011Zero Carbon Australia: We can do it
Hi several people, I retract. I had assumed that most of the pylon of a wind-generator was also concrete. If anybody else has published correct info, ignore that bit of my comment #41. I still do think there may be more potential in water-driven generation, specifically subsurface marine and/or tidal. As I say, I have really no idea if the claims made for thorium are credible. About the whisky and the cricket though, ;p -
Alexandre at 03:41 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
damorbel #703 Just a reference about emissivity values. ε=1 is not that bad an assumption at all.
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damorbel at 03:34 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
Re 701 RickG you wrote:- "Since I asked you to post your revised edition correcting Trenberth's short-comings on how it should appear, I gather your above comment is code for you can't support your claims?" Looking at the Trenberth pdf you cite: on p5 he has:- "At the surface, the outgoing radiation was computed for blackbody emission at 15°C using the Stefan–Boltzmann law R = εσT4, (1) where the emissivity ε was set to 1." Emissivity set to 1? As John McEnroe might have said "he can't be serious" Using such a figure for the Earth's surface inevitabl gives the wrong answer because the Earth's surface does not, by any stretch of the imagination, match the specifications of a black body. Worse still he claims 333W/m^2 from clouds. Clouds are even further from being black bodies. You make no reference to the fact that GHGs absorb and emit radiation only as a function of their temperature, not of their altitude. You must attach some importance to this. These things are the very essence of heat transfer in the atmosphere and anywhere else; I do think they should be examined by climatologists. -
pohjois at 03:21 AM on 21 March 2011Zero Carbon Australia: We can do it
@energy storage I would like to draw your attention to the interesting storage technology from the British startup called Isentropic. They store electric energy as a heat, claiming 80% accuracy of energy recovery. They use two storage tanks filled with gravel. One is heated to 500C and the other cooled to -150C, with the argon that is heated and cooled by heat pumps powered by electricity. Then, when the electricity is needed the heat pump works as generator recovering energy from the gravel. As far as I know they have built two small scale prototypes, working according to specs. They claim the storage costs between $55 and $10 per kWh, the latter for a large scale installations, which quite impressive. Certainly it could be very interesting alternative to the molten salt heat storage. Their web page. -
RW1 at 02:55 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
Tom Curtis (RE: 635), "RW1 @630, as it is difficult to carry on two discussions at once on the same thread, do you mind holding of on the discussion of the relevance of the light box until we have settled that it does not violate any law of thermodynamics? And to that end, do you agree that the light box does not violate any law of thermodynamics?" I'm not sure why you are asking me this. I do not believe that the GHE effect violates any of the laws of thermodynamics. -
Tom Curtis at 02:37 AM on 21 March 2011Zero Carbon Australia: We can do it
Further to my 44, at a reasonable efficiency (35%), the CO2 from the concrete foundation would be fully compensated for after 75 days. Of course, I have assumed that the foundations are entirely cement, whereas concrete consists mostly of steal and gravel, much reducing that figure. Also, some turbines require up to 800 tonnes of concrete for their foundations, increasing the time required by a factor of five. All in all, three months is about the top time that should be required. -
ranyl at 02:28 AM on 21 March 2011Zero Carbon Australia: We can do it
Rahul #23 - the plan is based on limiting warming to 2C, which is about 450 ppm, but only if every other major emitter follows suit. Dana but isn't that wishful thinking, that 450ppm is 2C, when the pliocene was 3-5C warmer at 350ppm? Basically 450ppm means we won't even be able to adapt! -
Tom Curtis at 02:10 AM on 21 March 2011Zero Carbon Australia: We can do it
idunno, further to your 41: Fluvial water power could not supply even a very small fraction of Australia's power needs. Hydroelectric power, on the other hand, already supplies a significant amount, but opportunities for new stations are limited. On the other hand, I personally believe that wave power is the way forward for much of Australia's renewable power needs. It is, however, an undeveloped technology and is unlikely to be readily available by 2020. (2040 is a bit different.) Finally, I have seen a number of people pushing Thorium as a magic bullet for nuclear safety. I have seen exactly the same people come out on mass a few days ago to declare that the problems at Fukujima power station were very minor and would not lead to significant exposure to radiation for anyone. That, in fact, the event was a squib and wouldn't even rate with Three Mile Island. Jokes were made comparing the expected radiation exposures from the event to those experienced from eating a banana (which are very slightly radioactive because of their phosphorous content). I take it with a grain of salt, or perhaps a grain of iodine. -
Tom Curtis at 02:00 AM on 21 March 2011Zero Carbon Australia: We can do it
idunno: CO2 emissions from fossil fuel power generation: Pollutant CO2 (Tonnes/GJ) Hard coal 0.0946 Brown coal 0.101 Fuel oil 0.0774 Other oil 0.0741 Gas 0.0561The average CO2 intensity ranges from 0.65 to 0.92 tonne of CO2 per tonne of cement across countries with a weighted average 0.83 t CO2 /t. The global average CO2 intensity in cement production declined by 1% per year between 1994 and 2003.
Around 150 tonnes of concrete are used in the foundations of a single wind turbine.
So, in the least efficient case, when we substitute wind for gas power generation, the cement in the wind power station would produce the same amount of CO2 as the Gas power station would produce after producing 2,460 GJoules. So, over 30 years, and assuming no power production due to maintenance for two days in every 7, the wind turbine would have to produce all of 3,650 Watts on average during operational times. For a 1.5 MW wind turbine, that represents an efficiency of 0.24%. Somebody was feeding you a furphy. And just a minor point, how much cement do you think there is in a gas fired power station? -
idunno at 01:42 AM on 21 March 2011Zero Carbon Australia: We can do it
Hi RickG, Sorry, absolutely no idea. -
RickG at 01:29 AM on 21 March 2011Zero Carbon Australia: We can do it
Idunno: 1. About 5% of all anthropogenic CO2 is generated by cement production. 2. So much cement goes into a wind turbine that it takes 30 years to save the equivalent in CO2 emissions. But how much of total cement production is used to construct wind turbines? -
idunno at 01:08 AM on 21 March 2011Zero Carbon Australia: We can do it
Hi all, I have a bit of a gripe against wind turbines. In your article, John, you say at one point "...zero-carbon, not counting emissions from construction."... Well, a couple of points of information, of dubious accuarcy, as I quote from a fallible memory: 1. About 5% of all anthropogenic CO2 is generated by cement production. 2. So much cement goes into a wind turbine that it takes 30 years to save the equivalent in CO2 emissions. I also strongly suspect that there is something to be learned from our forefathers here. Windmills were historically only ever widely built where there was absolutely no other choice, in areas such as Holland and the English Fens. Wherever anybody ever had a choice between building a watermill or a windmill, you see very few windmills. Now, I'm not at all sure that fluvial water power would be adequate to supply Oz's power needs, though it would be more reliable than wind, where available. But there might be a good deal of point you lot keeping a very close eye on the latest developments in tidal and otherwise maritime power generation. The latest scheme I heard of is to supply the Island of Islay in Scotland with all of its household power needs, and enough to run 8 single malt distilleries, entirely from submerged marine generators of some kind. Given that loads of Ozzies seem to have settled along the coasts, so you can practice surfing and being bad at cricket, and that the Roaring Forties of the Southern Ocean aren't that far away... Anyway, I'm no expert, and unlikely to be one any time soon, but just thought I'd say. Also, I only just came across this yesterday, and haven't looked into it at all, but I have seem it claimed that thorium is the magic bullet. Safe nuclear. Hmmmmmmmm... P.S. Anybody wishing to encourage Islay in its efforts to go carbon zero can probably find a most enjoyable way to express your appreciation in the most expensive section of the drinks aisle. -
RickG at 00:39 AM on 21 March 20112nd law of thermodynamics contradicts greenhouse theory
domorbel @ 700: Trenberth's diagram is deficient in so many ways it is beyond revision. Since I asked you to post your revised edition correcting Trenberth's short-comings on how it should appear, I gather your above comment is code for you can't support your claims? The data that goes into the schematic is massive and from numerous independent sources including ISCCP-FD, NRA, ERA-40, JRA, WHOI and HOAPS. It is not an ad-hoc meaningless diagram as you claim. "Again", read and absorb the paper (Earth's Global Energy Budget) by Trenberth et al that displays and explains the schematic in vivid detail. Here's the link: http://www.cgd.ucar.edu/cas/Trenberth/trenberth.papers/BAMSmarTrenberth.pdf -
Ken Lambert at 00:07 AM on 21 March 2011Zero Carbon Australia: We can do it
Original Post Has James considered the situation of a large weather system such as has deluged Queensland this summer where heavy cloud and rain persist for several days (up to a week or more) - and there is much reduced solar and not much wind. The molten salt would not cover more than 12-15 hours storage. Looking at the map - 4 or 5 power towers and some of the wind would not be producing much at all. What would be available to avoid power cuts and disruption to nearly all our work and domestic life? -
Bern at 23:51 PM on 20 March 2011The Climate Show Episode 9: Nuclear power and hot spots
Well, it was worth the time. Nice interview with Barry Brook, and John, I thought you did quite well explaining the tropical tropospheric hotspot (that *is* a mouthful!), but, yes, Gareth's one-line summary was a pearler. I hope you'll be putting that into the basic version of that rebuttal? :-) -
damorbel at 23:30 PM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
Re #695 RickG you wrote:- "All I can say is I don't know of a single climatologist on the planet when describing the Earth's Energy Budget, uses anything other than W/m^2." Is this a reason to accept it? Doing it the W/m^2 way without temperatures has, from the thermal physics point of view (even Newton knew it was wrong), never been justified; it is unjustifiable. Again, you wrote:- "If you are unwilling to accept that simple fact, then I suggest you redo Trenberth's schematic in your terms of temperature and show everyone how it should done." Trenberth's diagram is deficient in so many ways it is beyond revision. The so-called 'back radiation' has the concept behind it that there is a place in the atmosphere from where 'back radiation' comes; but even John Tyndall knew that this is not the case. He measured both the emission and absorption by GHGs and found that their emitted radiation was completely absorbed by gases at a lower temperature. This last means radiation emitted by GHGs is immediately absorbed and re-emitted by adjacent GHGs. This is so when the pressure and temperature gradient are zero; in the atmosphere the density reduces with altitude so the upwardly emitted radiation is not completely reabsorbed, an increasing %age gets ever higher until it escapes completely; that is the mechanism for heat radiation from the Earth.Moderator Response: [muoncounter] The only thing deficient in this thread is your continued repetition of the same 'objections' to the same accepted body of work. What is preventing you from taking your comments to Dr. Trenberth, rather than belaboring them here?
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