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Comments 102401 to 102450:

  1. We're heading into an ice age
    Re: cjshaker This is a reply to your comment over on the 'It's a 1500 year cycle' thread: ---------------------------------------------------------------------------------------------------------- Re: cjshaker
    "I think the bottom line is that climate modelers don't really understand the glacial cycle, nor how it really works."
     And your source for that claim would be...? You may want to actually read up on models. Suggested starting points can be found here, here, here, here and here. The Yooper
  2. The human fingerprint in the seasons
    #31: "Greenhouse warming is primarily a land based effect. " Surely you would include the Arctic as a place where greenhouse warming is significant... that is the Arctic Ocean?
  3. Stratospheric Cooling and Tropospheric Warming
    Mighty Drunken - 90 In the steady state, which is what my blog was all about, there is not less IR energy reaching the stratosphere from below. The same amount of IR reaches the stratophere. However, the nature of this radiation is different. There is less in the frequency range that CO2 absorbs and more in the range that sails past the CO2 totally unaffected by it. Bob
  4. Stratospheric Cooling and Tropospheric Warming
    damorbel - 85 An editorial error on my part. I meant to say "Venus does have a stratosphere". http://adsabs.harvard.edu/abs/1983KosIs..21..205A
  5. The human fingerprint in the seasons
    Humanity Rules: "That means 40-60% of the warming trend from a doubling of CO2 comes from the water vapour feedback. 40-60% of the GHG fingerprint comes from water vapour. The water vapour effect is not specific to CO2 but is a consequence of a warming world. All things being equal, any process that warms the world is going to have this 40-60% water vapour feedback." That is a ridiculous over simplification. Insolation varies, when you reduce it, you reduce the energy. CO2 is present all the time and is a 'storage' mechanism. The two have different impacts on how they would effect water vapour production and retention. It is somewhat duplicitous to accuse John of over simplifying the issue, when you yourself make a faulty assumption.
  6. The human fingerprint in the seasons
    Figure 1 shows green house warming started in 1980. Cool. I wouldn't expect the tropics to necessarily warm as much in summer due to solar increases. After all if you look at the globe between the tropics you will see that you are dealing with predominantly water, not land. Greenhouse warming is primarily a land based effect. Oceans absorb almost all the solar radiation they receive and transport that heat via currents to other parts of the globe (very low albedo). Because oceans absorb almost all the heat they receive there is nothing re-radiated for CO2 to absorb. Heating of the air over the oceans is primarily driven by water temperature which is why the temperature record over the oceans is based on sea temperatures. Ocean heating due to solar activity extends to a depth of 50m-100m during the summer. This heat is not all available to heat the atmosphere immediately but is transported via various currents and usually northward and southward. So again, Figure 1 points to an effect possibly caused by a shift of some sort in ocean currents or the transport of heat from increased solar activity farther north. England is seeing this effect right now. Most of the big hurricane activity this fall was confined to the North Atlantic taking huge amounts of heat out of the Gulf Stream which warms England and northern Europe and makes it livable.
  7. We're heading into an ice age
    Re: cjshaker (142) From the literature I've read, the Vostok and Epica cores were sampled every 0.5 to 2 meters, depending upon the depth (I don't recall offhand the spacing intervals from Greenland cores). The final several hundred meters of the Vostok core was deemed unusable due to heat penetration upwelling from Lake Vostok lying underneath the borehole at that point. The larger sampling interval actually carries with it fewer questions about the resulting resolution, due to the spacing involved. More frequent sampling might yield more data, but the resulting data would not necessarily add anything new. Changes in CO2 and temps in the paleo record occurred much more slowly than what we are physically measuring today. The Yooper
  8. Mighty Drunken at 00:11 AM on 4 December 2010
    Stratospheric Cooling and Tropospheric Warming
    @Tom Curtis post 83 Looking at your post and some other explanations about stratospheric cooling I think your description is more accurate than the post. The dominating factor for the cooling is not less IR radiation reaching the stratosphere from below, but the increased emission by increasing CO2 concentration. The difference between fig. 2 and fig. 3 show the cooling effect from less IR coming from below can only be slight. Gavin's post at real climate does seems to suggest greater concentrations of greenhouse gases warm the atmosphere up to a certain altitude and above that they cool as the balance between absorption from the surface and emission into space changes, as convection dominates in the troposphere though you don't get to see this effect in the troposphere. My post is only my understanding and is probably wrong!
  9. Stratospheric Cooling and Tropospheric Warming
    Re: Bob Guercio You are very much correct, sir. While I am aware that pre-1970 (or so) CO2 was primarily a lag/feedback to temps, I was remiss in not taking the time to point that out in my comment above. I will add verbiage to that effect in my comment. Apologies for adding to your workload. :) The Yooper
  10. Stratospheric Cooling and Tropospheric Warming
    Tom Curtis: "To see this, consider a hypothetical planet whose atmosphere is completely transparent at all wavelengths of electromagnetic radiation. In this case, its surface temperature will be its temperature as measured from space, ie, its effective temperature. The temperature at any point in the atmosphere above the surface will be less than the effective temperature, and the temperature profile of the atmosphere will be defined by the adiabatic lapse rate up to the thermosphere. (Like Venus, see graphic in 80 above, it will have no stratosphere.)" Not quite correct. Although this is an interesting game. If the atmosphere were transparent to electromagnetic radiation, the only way of transporting energy would be by conduction and convection. The only lapse rate would be as a result of convection and you may very well have an 'inverse' lapse rate, eg. hotter at the top over time. In fact it would get hotter and hotter, because the atmosphere wouldn't be able to emit the accumulating energy to space. Transparency = no absorption or emission
  11. The human fingerprint in the seasons
    HR, I think the disconnect here is that you aren't considering the fact that feedbacks must perforce follow the same 'fingerprints' as the forcings which cause them. That is, if a solar forcing were causing increased Summer temperatures that would indeed result in a water vapor feedback effect... during the Summer. When Winter arrived and the impact of the solar forcing declined the water vapor feedback would follow suit. Ditto geography... if a solar forcing were causing accelerated equatorial warming then we would indeed see increased water vapor feedback... near the equator. Yes, there is always going to be some overlap and 'flow' of feedbacks, but they must always be most pronounced in the same conditions the forcing causing them is. The law of cause and effect still applies.
  12. Renewable Baseload Energy
    Re: Ned (315) Quality words, ably spoken and spot-on; bravo, sir! More comments such as yours are needed to help maintain the decorum and high level of discussion already found on most of this blog, but lacking to some degree on this thread. On the other thread, being of like mind with you, I reached out to Peter and attempted to find common ground with him...and was rebuffed. The Yooper
  13. The human fingerprint in the seasons
    27 Argus: "How come, then, a majority of this year's heat records are from the tropics?" Perhaps because annual events are not climate trends.
  14. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel #270: "The idea that planetary temperature is affected by its albedo is quite mistaken." Your belief that you have any idea what you are talking about is quite mistaken. If albedo is irrelevant to temperature... why exactly is it that black asphalt gets hotter than white cement on sunny days? Or what magical property would be at work such that a planet with no atmosphere covered in white cement would be just as hot as an otherwise identical planet covered in black asphalt? That's the thing which gets me about nearly everything you say here... it isn't just that it is wrong, it is that any person capable of observing the world around them should know it is wrong. First you argue that a non-zero energy flow produces zero heating... now that reflection and absorption yield the same result. It's gibberish.
  15. Stratospheric Cooling and Tropospheric Warming
    Tom Curtis @83 " Therefore, I would have to conclude that stratospheric cooling with increased CO2 is primarilly due to increased efficiency at radiating away energy absorbed by ozone due to increased concentration of CO2. There would be a small additional boost due to reduced outgoing radiation of IR in the 15 micron (CO2) band; but that is ony a secondary cooling effect, and would have been a warming effect where it not for the presence of ozone in the stratosphere" vs my #79 "So are there two effects: 1) increased emission in the CO2 emissions bands increases thermal to radiative heat conversion and thereby reduces the temperature necessary to maintain overall heat balance AND 2) decreased absorption in the same spectrum because CO2 in the troposphere has already taken it out reduces the total heat input to the stratosphere " I think we are in agreement, so clearly we've both got something wrong ;-)
  16. Renewable Baseload Energy
    Peter Lang #292: "SEGS is a day time only plant." False. Didn't you read BP's post about how they are evil and dangerous because the heated fluid used to provide night time power caught fire once (though 0 people were harmed by this)? Seriously, if you guys are going to spread nonsense could it at least be consistent nonsense? Also: "This thread is about baseload. SCEGS is not baseload." Yes, it is. No other power plants are required to be 'on standby' to cover for them. They have natural gas power generation on site to make up for any shortfalls... but that's only 10% of total power generated.
  17. Renewable Baseload Energy
    Thank you, Ned. You've said what I would have, had I the wit (and the patience).
  18. Stratospheric Cooling and Tropospheric Warming
    Bob, neither Venus nor Mars have a stratosphere: But, contra damorbel, the absorber of shortwave radiation does not have to be O3 (or O2), as shown by the examples of Titan and the gass giants:
  19. Renewable Baseload Energy
    Peter Lang writes: ... the strong resistance to nuclear as is being expressed on the SkepticalScience web site ... I know from previous discussions that there are many of us on SkepticalScience who support nuclear power and who think that investments in nuclear power will need to be greatly expanded in the next few decades. So why aren't any of these people contributing to the discussion? I can only speculate, but here are three possible reasons: (1) Many of us support both nuclear power and renewables. My expectation is that reducing our use of fossil fuels will involve increased reliance on nuclear and hydro and solar and wind and geothermal and tidal power and biomass and ... well, you get the point. But you seem to be at least as motivated by the desire to attack renewables as by the desire to promote nuclear. Your approach, of pitting one against the other, is going to drive away those who support both. (2) On a more personal note, the aggressively combative style of many of your comments here may well to inhibit others from posting pro-nuclear comments (and almost certainly drives fence-sitters away from your position). You ignore and insult those who disagree with you, and convey the impression that you're not willing or able to objectively consider different sides to the debate. Your comments are riddled with absolutist language; there's no recognition of shades of gray or of the possibility that others might have any valid points whatsoever. Again, as someone who wants to build support for nuclear power (and other non-fossil sources) I know we need all the allies we can get. Intemperate outbursts -- like insulting comments about "Greenies" and repeated implications that your opponents are "irrational" -- don't help. I'm pro-nuclear, but I'm also a very committed environmentalist ... why should I participate in this thread when the main pro-nuclear poster is busily insulting people whom I identify with? (3) Although this thread is about energy sources, it's in the context of a site that is primarily focused on the science of climate change. Like others, I've gotten the impression that your knowledge of and interest in climate science is minimal to nonexistent. Your only purposes in posting here seem to be to (a) aggressively promote nuclear power, and (b) aggressively run down renewable energy (not necessarily in that order). This perception naturally further reduces people's interest in joining the discussion. Of course, this is all just one person's opinion ... but I would suggest taking some time to reflect on what you're trying to accomplish here and whether your efforts are likely to be effective in accomplishing that.
  20. The human fingerprint in the seasons
    20 Albatross I haven't had time to fully take in what Braganza is saying but the quote you pick out does highlight a problem I had noticed. Let's limit ourselves to just the most recent trend. Braganza seems to investigate two possible scenarios. 1) The warming is solely from human GHGs. or 2) The warming is solely from solar and volcanics. He then tries to see which best fits the observed trends. The problem I have is that those two options aren't the only possibilities. 2) would demand the position that CO2 increases have no possible role in temperature trends. Some sceptics might hold that position but many more hold a more nuanced position where they accept the role of CO2 as a GHG but are critical of the magnitude of that effect expressed by the IPCC. That would mean that a third possible option exists where the recent warming trend is in response to multiple forcing factors. Simply positing the two extreme positions and asking the question which one is the better fit does not fully investigate the problem. As I said before, but in respect to another issue, this is not an all or nothing problem. In fact your quote highlights the problem I have with John's presentation. In Braganza's words this is "consistent" with human GHGs not a fingerprint of it.
  21. Stratospheric Cooling and Tropospheric Warming
    Re #84 you wrote:- "Venus does have an atmosphere." What I wrote was:- "Venus has no stratosphere."
  22. Stratospheric Cooling and Tropospheric Warming
    damorbel - Venus does have an atmosphere. http://adsabs.harvard.edu/abs/1983KosIs..21..205A
  23. Stratospheric Cooling and Tropospheric Warming
    After carefull consideration, I believe the explanation of stratospheric cooling given in the original post is simply wrong. To see this, consider a hypothetical planet whose atmosphere is completely transparent at all wavelengths of electromagnetic radiation. In this case, its surface temperature will be its temperature as measured from space, ie, its effective temperature. The temperature at any point in the atmosphere above the surface will be less than the effective temperature, and the temperature profile of the atmosphere will be defined by the adiabatic lapse rate up to the thermosphere. (Like Venus, see graphic in 80 above, it will have no stratosphere.) Now, as we introduce CO2 into the atmosphere, what happens is that the altitude of the effective temperature gradually increases in height. As the temperature profile is still defined by the lapse rate, the temperatures at every altitude up to the thermosphere will also increase. Even if we exclude convection as a means of transfering energy in the atmosphere, and hence exclude the adiabatic lapse rate as a temperature profile, radiative transfer in an optically absorbing atmosphere will generate a lapse rate, indeed, typically a shallower (greater change in temperature for a given change in altitude) lapse rate than the adiabatic lapse rate. Therefore this reasoning should still hold. Looked at differently, and using Earth as our model, we need to consider that the effective altitude of radiation, ie, the average altitude from which radiation reaches space, lies several kilometers below the tropopause. Therefore most outgoing radiation at the tropopause reaches space, and the Beer-Lambert law is an appropriate approximation of the effect of changing CO2 concentrations in the stratosphere. Given that, then if we double the CO2 concentration we also double the amount of IR radiation absorbed by CO2 in the stratosphere. The amount of IR radiation outgoing from the tropopause will not itself double, but infact will slightly fall because the atmosphere is optically thick below the tropopause. Consequently, although the net radiation entering the stratosphere will fall in this scenario, the amount absorbed in the stratosphere will increase. Of course, the amount of IR radiation emitted at a given temperature will also double with doubling of CO2 in the stratosphere. The result is that, if the temperature of the stratospheric CO2 is less than the brightness temperature radiation emitted by CO2 in the troposphere, it will warm. If it is greater it will cool. Of course, had the temperature in the stratosphere followed the adiabatic lapse rate, it would have been less than that of the troposphere; and increasing CO2 would warm the stratosphere, all else being equal. But all else is not equal - the stratosphere is much hotter than the upper levels of the tropospere because of the absorption of UV radiation by ozone. Therefore, I would have to conclude that stratospheric cooling with increased CO2 is primarilly due to increased efficiency at radiating away energy absorbed by ozone due to increased concentration of CO2. There would be a small additional boost due to reduced outgoing radiation of IR in the 15 micron (CO2) band; but that is ony a secondary cooling effect, and would have been a warming effect where it not for the presence of ozone in the stratosphere. Having said all that, I now hope some one will knock some holes in my reasoning.
  24. Renewable Baseload Energy
    Ogemaniac, @ #303, “If we were to scale solar to about one hundred times what it is now, prices would likely fall more than half from where they are now. This would also be enough production capacity to replace every fossil fuel plant within a generation. The scale of this industry would be similar to that of the auto industry...certainly not impossible” Several points to make here. 1 You have posed some really big ifs. Do you want to wait in the hope that solar might be able to do the job sometime in the future? Do you want to continue to ban nuclear, or continue to put such onerous restrictions on it that it is uneconomic, so we delay another 20 years or so? Do you want to take the risk? Because that is what is happening as a result of the strong resistance to nuclear as is being expressed on the SkepticalScience web site and other web sites dominated by contributors with similar beliefs. 2 “Scaling solar to one hundred times rimes what it is now” would not make a dent in the amount of generating capacity we would need in 20 or 30 years time. It would be insignificant. 3 If you halved the cost of solar thermal that has sufficient storage to do what the ZCA2020 report assumed (which is totally insufficient anyway), the cost would still be about five times the cost of nuclear. Gemasolar (Spain) Generating Capacity = 17MW Storage = 15h Energy pa = 100,000MWh Cost (2009 €) = €230 million (200 Cost (2010 A$) = $395 million Cost per kW = $23,225/kW Cost per average kW = $34,587/kWy/y For comparison nuclear = $4,500/kWy/y So, the cost for Gemasolar with 15h storage (not baseload) is about 8 times higher than nuclear Halve the solar (and don’t reduce the cost of nuclear) and solar is still 4 times higher than nuclear. Reduce the cost of nuclear over the same period too, and solar would still be around 6 times higher than nuclear. Make solar thermal baseload capable and solar would be probably 20 times higher cost than nuclear (if it is even possible to do it, which I doubt) I am sure someone here will pull out some other figures from another plant. Please do but try to keep a sense of perspective. Differences between plants are not significant unless they are at least a factor of five lower cost per kWy/y, given the size of the discrepancy between solar an nuclear. Please provide the source of your figures, present the equivalent figures to those I’ve shown above and show how you calculated them. By the way, the new solar PV station recently commissioned at Windorah in Queensland cost $4.5 million for 130kW, 360MWh/a, = A$34,625/kW, = A$109,500/kWy/y. Key Point: Solar thermal is totally uneconomic, and probably can never be a viable baseload technology. Even if we halve the cost of solar thermal it is many time more costly than nuclear. If we could make it capable of baseload generation it will be many times more expensive still. This is why I say there is no realistic prospect of solar thermal being economically viable as a baseload technology. Sources: http://www.nrel.gov/csp/solarpaces/project_detail.cfm/projectID=40 http://europa.eu/rapid/pressReleasesAction.do?reference=BEI/09/224&type=HTML http://www.solarpaces.org/Tasks/Task1/Task%20I.pdf http://ecogeneration.com.au/news/windorah_solar_farm/011780/
  25. Stratospheric Cooling and Tropospheric Warming
    Daniel Bailey - 78 garythompson - 77 This graph does show a correlation between CO2 and temperature. However, it may not show the correlation that you want. In this graph, temperature changes occur a few hundred years before CO2 changes. CO2 does contribute to the temperature increase but as a feedback rather than a forcing. This is often used by contrarians to debunk the present day issue of CO2 causing the temperature to rise. Bob
  26. The human fingerprint in the seasons
    Quoting from top post: "Solar warming should result in the tropics warming faster than the poles. What we observe instead is the poles warming around 3 times faster than the equator." How come, then, a majority of this year's heat records are from the tropics?
  27. The question that skeptics don't want to ask about 'Climategate'
    Physics based models still make a host of assumptions? All models make a host of assumptions, including those written by the atmospheric particle modelers. Chris Shaker
  28. The question that skeptics don't want to ask about 'Climategate'
    "actually thoughtful": If we saw a temperature change that exceeded that from the historic glacial cycle, it'd be a lot easier to believe in AGW. So far, the global warming that we're seeing appears to be a natural part of the warm phase of the glacial cycle. We reached 4.5C warmer than today (1950) during the previous warming phase, 130,000 years ago. http://news.nationalgeographic.com/news/2007/07/070705-antarctica-ice.html Chris Shaker
  29. 2nd law of thermodynamics contradicts greenhouse theory
    Re #266 KR you wrote: "Photons don't have temperatures (cold, warm), they have energies." The temperature associated with photons comes from the Planck energy distribution, the peak of the curve tracks the Wien displacement law In the same way as a gas has a distribution of energies following the Maxwell-Boltzmann distribution according to its temperature; photon energy follows Planck's law. But, since the bulk gas has the average temperature of all the molecules, this also means that the individual (isolated) molecule has its own temperature. In the same way a photon also has its own temperature, related of course, to its energy. This goes further; a planet orbiting a star is immersed in photons emitted by the Sun, the number of photons intercepted by a planet is reduced by the inverse square law but this is the only reduction, making the equilibrium temperature of a planet a function only on the Sun's (photon) temperature and the planet's distance from the Sun. The idea that planetary temperature is affected by its albedo is quite mistaken.
  30. It's a 1500 year cycle
    My further comments are posted at We're heading into an ice age http://www.skepticalscience.com/argument.php?a=53 Chris Shaker
  31. We're heading into an ice age
    Thank you for the explanations about the graph. What you say makes sense. I think this implies that the cores are sampled for analysis every so many mm? Chris Shaker
  32. The human fingerprint in the seasons
    16 Daniel Bailey I guess a definition of a 'human fingerprint' would help. Maybe John (or you) could provide one? For me it means evidence that stands alone in identifying a human component and excludes all other possibilities. Without both of these it's just evidence that's consistent with CO2 warming. A discussion of whether there is or isn't a TSI trend will not get us any closer to understanding why this is a fingerprint. More back of the envelope calculations. Solar warming would contain a 40-60% GHG component from water vapour. What about IPCCs estimates of CO2 warming? 0-33% comes from albedo and other non-GHG warming forcings and feedbacks and 66-100% from the GHG component (about half that from the water vapour feedback the rest directly from human GHGs). Can John's graph differentiate between a 40-60% GHG warming signal and a 66-100% GHG signal? If it can't then it's not a fingerprint of human warming. As I said before, in John's written description of what a solar fingerprint will look like he seems to ignore feedback and focus solely on the direct effect from changes in TSI. DB you seem to be taking two steps forward. John introduces the mythical "solar fingerprint' to the the discussion. I'm only going with John's flow here. If there is a problem with considering a solar fingerprint then maybe you should direct your criticism toward him.
  33. Stratospheric Cooling and Tropospheric Warming
    Humanity Rules: "That in a nutshell seems to be the problem." Then I hope you are not a teacher. You don't go in guns blazing and teach someone who knows nothing about science, the complexity of a subject that only an experienced scientist knows. You start with simplicity and add complexity as the student has learnt the simpler principles. That applies just as much to climate science, as it does to carpentry, stonemasonery or welding.
  34. We're heading into an ice age
    scaddenp said at 07:05 AM on 23 March, 2010 "I hate to be reiterating an old point but its all about rate. The transition into and out of ice age is extremely slow by human terms. (around 10,000 years). The rate of warming we are creating is by comparison very fast. Rates of change that overwhelm species capacity to adapt are the danger." It seems that these claims are incorrect. Natural systems have caused huge and rapid temperature change in the recent past. http://www.scientificamerican.com/article.cfm?id=ice-core-reveals-how-quickly-climate-can-change "Following this abrupt shift, as much as 20 degrees Fahrenheit (10 degrees Celsius) of warming occurred over the subsequent decades—a change that ultimately resulted in at least 33 feet (10 meters) of sea-level rise as the ice melted on Greenland." http://www.sciencedaily.com/releases/2008/06/080619142112.htm "The ice core showed the Northern Hemisphere briefly emerged from the last ice age some 14,700 years ago with a 22-degree-Fahrenheit spike in just 50 years, then plunged back into icy conditions before abruptly warming again about 11,700 years ago. Startlingly, the Greenland ice core evidence showed that a massive "reorganization" of atmospheric circulation in the Northern Hemisphere coincided with each temperature spurt, with each reorganization taking just one or two years, said the study authors." Note that the Woolly Mammoth, giant sloth, and Sabre tooth tiger went extinct during one of the most recent temperature excursions, only 12,900 years ago. Chris Shaker
  35. The human fingerprint in the seasons
    Daniel Baily #16 "all other forcings have been flat or declining " Correction. Albedo has changed. Human waste heat has only been increasing. Urban heat islands are unfortunately real. Waste heat is real energy, over and above that provided by the sun. (i.e., unlike the flash-in-the-pan diurnal greenhouse effect.)
    Moderator Response: [Daniel Bailey] Please do not reprise the waste heat discussion here. 356 comments on that topic and counting; if you feel you have something to add that shows waste heat amounts to more than 1% of GHG forcings, go back to that thread and comment on it there. UHI has been thoroughly debunked and rebunked, both here at SkS and by Tamino, to mention but two places. Use the search function to find the most appropriate UHI thread. Waste heat and UHI comments are off-topic on this thread.
  36. Renewable Baseload Energy
    scaddenp, I should have explained for others that a small proportion of wind power with a large proportion of hydro generating and storage capacity can work because when the wind is blowing the water stored in the reservoir (stored potential energy) is saved because the hydro generators are turned down when the wind is blowing. When the wind power decreases the hydro power is turned up to meet the demand. In short, wind power avoids using stored hydro energy. Whether this is economic or not, is another question. It can be, in some situations, just! In New Zealand you, like Australia, have a ban on (unprintable), so we have no way of knowing if your generating system is the least cost option.
  37. Renewable Baseload Energy
    scaddenp, I agree that wind can make an economically viable contribution where it is matched with large hydro generating capacity. This is the case in Denmark/Norway, New Zealand, China, Brazil and parts of Canada (although they are beginning to realise that it is not economically viable at all even with huge baseload hydro generating capacity).
  38. Renewable Baseload Energy
    People, This discussion is silly. The questions posed in the lead article have been answered - and supported in previous posts. Read back through the posts and the links provided. 1. Yes, baseload generators are essential. (about 75% of our electricity demand is baseload). 2. No. Non-hydro renewables cannot provide a significant proportion of baseload generation (except where there is volcanic geothermal) 3. There is little likelihood that non-hydro renewables (and volcanic geothermal) will ever be commercially viable (at the scale required to make a significant contribution). All the sources to substantiate these statements are provided in earlier posts.
  39. It's a 1500 year cycle
    The numbers I see for temperature increase caused by man claimed by the IPCC is about .7C. We reached 4.5C higher during the previous glacial cycle. I think the bottom line is that climate modelers don't really understand the glacial cycle, nor how it really works. Chris Shaker
  40. Stratospheric Cooling and Tropospheric Warming
    Re #40/41 Bob Guercio you wrote:- "the fictitious planet that I am using is a physical impossibility" You don't need to imagine a fictitious planet to see that O2 is essential for a 'stratosphere effect'. Venus has no stratosphere, the image below is a temperature profile of the Venusian atmosphere from 30km to 100km. (the lower part contains various extrapolations to the surface, further, you can open the image in another application to get a better quality). The green/red horizontal lines 2/3 up on the left are at 50-60km altitude and a pressure detween 1000 and 2000mB - thus the profile is similar in pressure terms to Earth.
  41. The human fingerprint in the seasons
    I like this post showing strong data supporting the AGW argument. Do the people arguing WV claim that the sun evaporates more water in the summer and then wind blows it to the other hemisphere so that it is warmer in winter? The WV would rain out on the way. WV would enhance solar warming during the summer but not during the winter. This is the opposite of CO2 warming that is observed. Can the WV people clarify the mechanism whereby WV causes warming similar to CO2 which is always present in the atmosphere. Please provide a link to a detailed argument that supports your claims.
  42. Renewable Baseload Energy
    muoncounter @392 and referring to my post #297. You are correct in that my statement in #297 is loose and not correct. I should not have said the "consumer pays" 5 to 20 times more for electricity from renewable generators. What I should have said is that the distributor must pay a higher price for electricity for renewables. The LCOE (cost) of electricity is 5 to 20 times higher from renewable generators than from conventional power stations. The cost must be recouped by the power station so, over time, on average, the wholesale price paid by the distributor must be at least that much higher for electricity generated by renewable energy generators than by conventional power stations. The distributors higher cost must be passed on, with profit and all the other costs, to the consumer as a higher price. I hope this clarifies my too brief statement that you so rightly picked up on :)
  43. Renewable Baseload Energy
    Ogemanic, "Solar has been tracking right along this path the last several years, and prices are lower than ever." I see. (sarcasm alert) In that case, why did the cost of solar generated electricity in the USA increase 30% beteween 2009 and 2010 (part of an ongoing upward trend), and why did the cost of Solar Tres / Gemasloar (Spain) increase by 250% from 2005 to 2009? Furthermore, why did the NEEDS analysis project that costs would fall by about 30% (from memory) between 2007 and 2010, yet they have increase by over 100% (in real terms). You might also apply your argument of decreasing cost with increasing roll outs to the unprintable technology. Once we get over the fear factor and remove the impediments in the western democracies, the cost will reduce for this technologuy too. China is now building it NPP's for $1,500/kW in 52 months. Ogemanic, I do no what you are getting at, but it is based on the price of solar panels not the full cost of commercial scale solar power stations (200 - 1000MW) with 24 hour generating capability including through prolonged periods of overcast weather and short winter days.
  44. It's a 1500 year cycle
    I don't have any idea where the 1500 year cycle claims come from. I take exception to the claim that "Ancient natural cycles are irrelevant for attributing recent global warming to humans." Chris Shaker
  45. Renewable Baseload Energy
    Peter, Your claim that renewables must currently generate 24/7 in order to supply 24/7 in the future is absurd. Why should we build expensive storage today when it will not be needed for decades? Demonstration plants have shown that it is possible to store the energy. It is currently not stored because storage is not needed with the current grid. Solar plants generate power during peak demand, why would they store the energy to sell later at a lower price? When you make absurd claims like this no-one listens to what you say and it makes nuclear proponents look bad. I have moved further away from nuclear due to your arguments. If your arguments are the best nuclear can do, nuclear is not worth much. You have made your point numerous times on this thread that you think that renewables cannot supply baseload. You have not provided convincing arguments or links to peer reviewed studies. I suggest you stop posting more of the same, the rest of us know what you think and disagree. If you try to link a new study every time you post you will contribute much more to the discussion. If you cannot link to a new study, you are just repeating yourself and wasting everyone elses time. I am still paying monthly for an unapproved nuclear plant which will not generate electricity for at least 10 years. If nuclear is so good why do I have to subsidize it for 10 years? I pay for renewables only when I get the electricity. We agree that wind generates GWhrs of electricity, without subsidy, economically in Texas using wind. We agree that nuclear cannot be used in much of the developing world. You have made no suggestions of how to deal with the nuclear waste. You are a proponent of thorium reactors that have not yet been built and cannot contribute to electricity generation for at least 20 years. I am not convinced by your repeated rants. Post on the what should we do about renewable energy thread that you previously hijacked for nuclear discussion if you want to continue the debate, not here. I notice that you have stopped responding to the questions raised there. Do you find them impossible to answer?
  46. Renewable Baseload Energy
    muoncounter, scaddenp is correct. The relationship between cost and price is extremely complex. For example, in the Australia system coal generated electricity may be around $30/MWh but the price bid ranges from -$1,000 to +$12,500/MWh. The price changes rapidly and by very large amounts. That is the wholesale price. The retail price includes the transmissions and grid operating costs, distribution, retail operating costs (including managing and paying the fees for mandated renewable energy, profit, etc. Price is extremely complicated. Better to stick with Levelised Cost of Electricity (LCOE).
  47. Renewable Baseload Energy
    scaddenp, Yes, France is required by EU requlations to build 20% renewable by 2020 (or something like that) despite it already having near zero emission electricity. France is required to buy electricity from the renewables first (obviously - otherwise they wouldn't be built). That shows how dumb all this renewable energy advocacy is. I'm with you regarding dumping subsidies and market distortions. I argue to dump all subsidies, all regulations that favour one technology over another, all tax breaks and remove all market distortions. Once that has been done, and not until it has been done, then consider what else needs to be done. However, I expect if that is done properly, there may be no need to do much more because low emissions electricity would be cheaper than fossil fuel generation and would become even cheaper as time progresses. If we do need to give some extra shove then, as a first step, I favour regulating emissions for new generators, with the increasingly restrictive emissions requirements being phased in between now and 2025. For existing generators I'd advise them they will have to meet increasingly stringent emissions rates from a date to be determined. Once the G20 countries reach agreement on a way to price emissions then we would, of course, be part of that international agreement.
  48. The human fingerprint in the seasons
    The final sentence of the article reads … What we observe instead is the poles warming around 3 times faster than the equator. I have read that Canadian/Alaskan temps have risen by 5C, a lot more than 3 times the increase at the equator – or does the “3 times” refer to Antarctic temp increase rather than Arctic? Can anyone refer me to material which explains difference between average global temps and polar arctic temps please.
    Moderator Response: [Daniel Bailey] This post by Ned covers much of that. The use of Arctic-only stations relative to the global datasets shows the ongoing polar amplification present in the Arctic.
  49. Stratospheric Cooling and Tropospheric Warming
    Sphaerica 71 "it could/would still be a net emitter in the end, but just with a smaller differential, and with some IR redirected back to the surface." I wouldn't dispute this, but if it is true, why do we need to consider the troposphere at all, as in the original post? Surely if CO2 is always a net emitter, then adding it will always reduce the temperature, regardless of what spectrum of radiation comes up from the troposphere? Your explanation was also my original understanding of statospheric cooling - that CO2 made the stratosphere more efficient at radiating than a blackbody by converting thermal energy to radiation at the absorption bands. To maintain the same overall emission, the temperature drops. But Bob's post says it's a whole lot more complex than that. Actually, as I write the last paragraph, maybe that's it - the internal radiative emission from the stratosphere (as opposed to mere transmission of ground level or troposheric radiative heat) actually falls because of reduced tropospheric tranmission in the CO2 absorption band. So are there two effects: 1) increased emission in the CO2 emissions bands increases thermal to radiative heat conversion and thereby reduces the temperature necessary to maintain overall heat balance AND 2) decreased absorption in the same spectrum because CO2 in the troposphere has already taken it out reduces the total heat input to the stratosphere
  50. Stratospheric Cooling and Tropospheric Warming
    Re: garythompson (77) Try this: (BTW, the zero-year baseline is 1950) Source here. Note that there exists much more than mere charts establishing a link between rising CO2 levels and rising temperatures. ----------------------------------------------------------------------------------------- [ - Edit - : In the graph I supplied, temperature changes occur a few hundred years before CO2 changes. CO2 does contribute to the temperature increase but as a feedback rather than a forcing. CO2 can act as a forcing (and has, post-1970 or so), but it's effects as documented in the paleo-record have been as a feedback to temperatures. The biggest exception to this is the PETM, which (unfortunately) is beginning to look more and more like the best comp for the modern era. Time will tell. - End Edit - ] ----------------------------------------------------------------------------------------- The Yooper

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