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Ogemaniac at 13:52 PM on 1 December 2010Renewable Baseload Energy
"The point of this post, that renewables can provide base load energy, is true. However, it is NOT accurate to claim that renewables can provide economically competitive base load energy" Economically competitive vs what? Subsidized-up-the-ying-yang fossil fuels, whose free public garbage dumping rights alone are worth something on the order of a trillion dollar per year? -
HumanityRules at 13:45 PM on 1 December 2010A basic overview of Antarctic ice
#69 muon Thanks for playing. I acknowledged later my data presentation was a distraction from V09 data but I don't think it really matters because as you say it's all about trends. So please stay with V09's original data. It's not just about whether there is a downward trend it's about whether there is an acceleration in that trend. I think V09 (along with Rignot 2008a) appear on the surface to be the strongest supporting data for that outlook based on the Copenhagen Diagnosis figure. So the blip matters here. Look I have to disagree with your final paragraph. Bad data analysis is bad data analysis. There's no running away from that, no matter how inconsequential you think it is. -
Daniel Bailey at 13:40 PM on 1 December 2010Twice as much Canada, same warming climate
Re: gallopingcamel (73) Let me know or send me a link. I'd be interested in hearing your ideas on those topics. Thanks! The Yooper -
gallopingcamel at 13:30 PM on 1 December 2010Twice as much Canada, same warming climate
Daniel Bailey, Thanks for your comment. This is a great blog as it does not censor non-conformists (such as camels and BPs). I visited NOAA in Asheville; the most senior person I met was Tom Peterson. What he told me was "very enlightening" and I am still trying to digest it all, especially climate change at high latitudes such as Greenland and arctic Canada. I hope to have my ideas organized in a few weeks with the idea of posting them on "Digging in the Clay". -
Tom Dayton at 13:14 PM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
damorbel, people have asked you, repeatedly, the simple and essential question "What happens to the photons from sources cooler than the target?" You have ignored those repeated questions, despite them being at the heart of the topic of this thread. Please answer my most recent version of that question: What happens to the photon named Greg? -
muoncounter at 13:07 PM on 1 December 2010A basic overview of Antarctic ice
#67: "nobody has even acknowledged whether they see that short-lived upturn around 2006." HR, I'll play. I see it! And I acknowledge it appears just as you describe: 'a short-lived upturn'. Unfortunately, your graph in #55 is in 'sea level equivalents (cm) anomalies', so there's some appling and oranging going on. However, this blip does not eclipse the downward trend, which is present no matter how you slice and dice these data. Trends, its all about trends. Agnostic at #43 made it quite clear that this is one complicated subject and we're trying to sum it up with one number. It's a bit like a conversation that someone might have over whether the stuff in their freezer is thawing evenly -- while their house burns down. -
Daniel Bailey at 13:03 PM on 1 December 2010A basic overview of Antarctic ice
Re: Steve L (26, 28, 65) Sorry I missed your earlier questions! You are correct in that austral summer solstice is important (due to the sun being the highest above the horizon at that point), but remember that summer minimum ice extent is also important, as even low-angle sun hitting open water late in the melt season still gets absorbed, contributing to warming. As you noted, this then contributes in the Arctic to an extension of the fall melt season (the fact that melt there is now actually lasting into fall is remarkable). In fact, Arctic area and extent have declined in every month:
and ice-edge latitude has moved poleward as well:
The money shot for the Antarctic is this: poleward retreat of sea ice goes only so far. The continent, with its lofty elevation and citadel of cold (buttressed by the ozone-hole-strengthened circumpolar vortex) is relatively immune for now to the summer suns' direct effects.
The Arctic has no such reinforcements at its back. Latitudinal retreat will continue until the pole is reached, and summer ice known to millennia of mankind will be no more. Cryosat-2 data will provide definitive data on Arctic ice mass & will be the final (until we get something better) arbiter for ice data for both poles.
Per Tamino's post, Antarctic summer ice minima increase is not statistically significant.
When the Southern Ocean warms enough, then we will see an early and longer melt season in the Antarctic (with trends growing similar to those I showed you for the Arctic). Which is bad news for the WAIS in general and the PIG in specific...
Thanks for reminding me about Tamino's post!
The Yooper
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HumanityRules at 12:43 PM on 1 December 2010A basic overview of Antarctic ice
64 Philippe Chantreau My point hasn't got as far as the wider perspective on the subject. It's specifically about the way the data is used in Velicogna 2009. If data is used badly in making an argument there is no defense for that work in the fact that it is in agreement with other studies. I don't disagree with your general argument that there is strength in independant well crafted analysis supporting a particular interpretation. My question is whether we have that in the first place. I'm still looking for a bold defence of V09's method of data analysis given that I recognise important variablity in the data. Of the few people who've responded to my post nobody has even acknowledged whether they see that short-lived upturn around 2006. Philippe please have a go at critiquing my specific criticisms of the data, I'm happy to discuss the merits of mutaully supporting evidence after I've got over the hurdle of whether the V09 estimates are meaningful. -
robert way at 12:41 PM on 1 December 2010A basic overview of Antarctic ice
HumanityRules, Perhaps the reason Velicogna uses 2006 as a start date is because the rate of ice loss after 2006 was greater and because Rignot et al. 2008 a,b measured accelerations in glaciers for sure between 2006 and 2007. I also noticed that you have yet to address the issue that multiple methods are supporting the same answer. It is because of the aforementioned uncertainties that we should look for independent measurements in agreement. That is the crux of science. We acknowledge there is the potential for error in analyis but when we see it repeated with similar conclusions and different methods then we conclude that there is a foundation upon which claims can be built. -
Renewable Baseload Energy
An Australian study (very small) on wind speed correlations: Gloor 2010 "Due consideration must be given to local conditions when assessing these correlations. Take Carnarvon and Geraldton for example. Though they are fairly distant from each other (446 km) they show a strong correlation (0.47) as they are in the same wind conditions of the Trade Winds that blow constantly and consistently over a wide area. So wind farms in Carnarvon and Geraldton would tend to go offline at the same time despite being quite well separated in distance. Contrast this with Perth Metro to Albany. Albany is in the southern ocean wind pattern, well out of the trade winds and has a lower correlation (0.33) with Perth Metro despite being only (375km) distant. So wind farms in Albany could continue to provide power to Perth when the wind farms around Perth would be at low output potentially. This is taking advantage of the different wind regimes. ... The graph of correlation with distance for these datasets does show a decreasing correlation with increasing distance however the spread of data is quite large. There is not a neat line of decreasing correlation but more a broad range. However it does support the idea that widely spread wind farms, taking into account the wind regimes of the sites, can be less correlated than closely spaced wind farms. If the correlation relationship held up then these wind farms, if connected together, could perhaps provide more reliable power than a single wind farm or group of closely grouped wind farms." -
Renewable Baseload Energy
Peter Lang - First, what you want is negative correlation between wind sites. If you use sites with negative correlations, when the wind dies at one site it's high at another - say sites on opposite sides of the country. And using a mix of renewables (solar and wind) reduces correlation of down times even more. Second, you are once again focusing on a single area of Australia, the South-East. As I stated in an earlier discussion, widely separated sites are required. I don't know the details of Australian wind samples, it may not be possible to get sufficient negative correlation to supply significant baseline. On the other hand, it quite possibly may. It certainly seems possible in Europe, but again I don't have detailed multi-site wind/sun surveys with correlations in Australia. Third, with sufficient negatively correlated sites, base capacity, and storage, your argument that wind farm backups would burn more gas than straight non-stop natural gas turbines is, frankly, simply ridiculous. That requires near-constant use of the turbines with stop/start cycle energy outweighing the time off due to wind input - and with uncorrelated sites and storage, that's not going to be the case. Personally, I consider Masterresource a strongly biased and poor source (like WUWT) - I would prefer seeing calculations by someone without an axe to grind. The article you pointed out on baseline requirements is interesting - instant loads covered by generators, intermediate by gas turbines. Solar cannot cover the 'generator spin' loads, although wind can. There are certainly some points worth considering there, points directly related to renewables. I would strongly suggest (Moderators - opinions?) that any discussion of nuclear energy pros and cons remain on What should we do about climate change?, where that has been hashed out over 379 comments to date. Please do not hijack this thread.Moderator Response: [Daniel Bailey] Agreed. This thread is about Renewable Baseload Energy. Comments about nuclear energy are off-topic here, and should more appropriately be posted on the What-should-we-do-about-climate-change thread. Thank you all in advance. -
Steve L at 12:08 PM on 1 December 2010A basic overview of Antarctic ice
Re #62 & 63, I posted comments similar to what Bill wrote here (see #26 and 38). My comments were ignored. :( DB(Yooper) -- the fact that Antarctic sea ice melts back to the continent by the end of the austral summer does not contradict the fact that there is sea ice there during the austral summer solstice. Cryosphere today says the current sea ice area there is 10.9 million sq km. There will still be millions on December 21 and even January 21. There could be as much as a half million sq km more ice than the 1979-2008 average over that time period (currently 0.3 million sq km). This anomaly in reflective area may not be as great as is observed in the Arctic during the boreal summer solstice (can someone check?), but we shouldn't pretend that it doesn't exist. -
Peter Lang at 12:01 PM on 1 December 2010Renewable Baseload Energy
Rob Honeycutt, Have you heard of the Pareto Principle. One application is to put most of your effort into what can have the largest effect. Non hydro renewables may provide 10% of future power supply - perhaps. Nuclear and pumped hydro can provide 100% now. It has been doing nearly that for the past 30 odd years in France and providing low cost electricity as well. We have a proven way to cut emissions at low cost. Why waste any more time chasing the renewable dream. @180 last paragraph you put out the often stated argument which in effect is "I am not against nuclear, but renewables will be part of the solution so let's focus on them". This has been going on for 20 years in Australia so no one is prepared to remove the impediments to nuclear in Australia. We need to put our main effort where we can get the biggest gains. That is on nuclear. So I'd urge all those who want to cut emissions to put their efforts into changing the opinions of the anti-nukes - the environmental NGOs, media (especially ABC), and the politicians. It is far more important, and urgent, to remove the impediments to nuclear than it is to implement a carbon price. Once a carbon price is implemented then the many impediments to nuclear and favouritism for fossil fuels and renewables will be very hard to remove. We need to focus first on removing the impediments to nuclear. -
Peter Lang at 11:51 AM on 1 December 2010Renewable Baseload Energy
Rob Honeycutt, Investor dollars are being poured into renewables because the government is mandating them and subsidising them. Wind power is subsidised by about 100% to 150% and solar by about 1000%. The investors are guaranteed the income from government and consumers for 20 years. Under such conditions of course investors will invest. The point I'd make is, people contributing on Skeptical Science think they can do objective research. But just wishing and wanting is not going to make renewables viable. They are not viable and probably never can be (at more than about 10% of the total generation). There is far too much to explain in the comments field. I'd urge those that are seriously interested to actually read the links from people in the industry, not just the renewable energy advocates. The anti nuclear protesters over the past 40 years (the same people as the renewable energy advocates), by blocking nuclear have caused CO2 emissions to be about 20% higher now than they would have been if the development of nuclear power had been allowed to progress in the Western democracies over the past 40 years. Not only are emissions 20% higher now than they could and should have been but they will remain much higher for many decades because the development process was stalled and it will take decades to recover to catch up. That is what irrational advocacy does. So, I urge you that think you can do objective research to start informing yourselves. Look beyond the spin propagated by the so called environmental NGO's like Greenpeace, WWF, FoE, and the Australian Conservation Foundation. -
Peter Lang at 11:39 AM on 1 December 2010Renewable Baseload Energy
KR, There is another really important point to understand. The claims about how much CO2 emissions are avoided by wind farms are bogus. It seems that wind farms avoid littel if any CO2 emissions and can actually cause more emissions than if there is no wind in the system. This explains: http://www.masterresource.org/2010/06/subsidizing-co2-emissions/ -
Peter Lang at 11:37 AM on 1 December 2010Renewable Baseload Energy
KR, To see the positive correlation across the Australian NEM wind farms look at the charts for - August 2010 (seven cycles of power output from 20% to 80% of capacity), http://windfarmperformance.info/documents/analysis/monthly/aemo_wind_201008_hhour.pdf - May 2010 (Capacity factor averaged less than 5% for a week and was negative on 65 5-minute intervals during that week) http://windfarmperformance.info/documents/analysis/monthly/aemo_wind_201005_hhour.pdf To get the data: http://www.landscapeguardians.org.au/data/aemo/ -
Philippe Chantreau at 11:36 AM on 1 December 2010A basic overview of Antarctic ice
HR says: "The conclusions in the Velicogna paper should stand on their on feet irrespective of what other authors have published." That only is to be understood in terms of its internal logic and how results are supported by data used. It does not go beyond that. When considering the field of study, the conclusions of a paper should always be weighed with what else has been published before and after on the subject. Why should it not? -
Peter Lang at 11:27 AM on 1 December 2010Renewable Baseload Energy
KR, This talk about wind power and solar power being able to provide baseload generation is just nonsense. I'd suggest you and the others pushing this advocacy of renewables should take more notice of the people in the industry than of the academics wanting renewables at any cost. The Australian NEM is the largest grid in the world in arial extent (so I understand). Wind farms are distrobuted over the southern part in an area 1200km east-west by 800 km north-south. This grid demonstrates high correlation of wind power output. In May we went for a week with almost no output from all the wind farms spread over this area - at times the output was negative by up to 4 MW - thaty is the wind farms were drawing more power that they were generating. The same is being found throughout the world. However, even if positive correlation was the case over much larger areas, the cost of the transmission systems and of the grid power and frequency control systems is enormous. In Australia, the current capital cost of wind farms is aboiut $2900/kW. Grid enhancements allow $1000/kW. Gas back up about $1000/kW. Total about $4900/kW. That is for about 30% of the energy coming from wind power. If you want say 90% coming from wind power (on average) then the cost is three times higher for the wind farms and transmission. The total cost per average kW is 3x($2900+$1000)+$1000 = $12,700/kWy/y. For comparison, nuclear would be about $4,500/kWy/y. This is based on the newly contracted price for the 5400MW nuclear power station being built in UAE by a Korean consortium; the cost is $3,800/kW with say 85% capacity factor, $3,800/85% = $4,470/kWy/y. The comparison is not even close. If we could just throw off the blinkers and stop the wishful thinking about renewable energy, the answer to cutting emissions from electricity generation is obvious. Did you read the links I provided. Have you read the the "Zero Carbon Australia - Stationary Energy Plan - Critique"? Links were provided by Quokka at 2:18 this morning. I'd urge you and others who are objective to read the critiques. -
archiesteel at 11:05 AM on 1 December 2010Renewable Baseload Energy
@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 info while making sure that quokka and Peter Lang are repeating the same old arguments about why Nuclear is the *only* solution, disregarding the reality of what renewables have accomplished in just a few years while diminishing the real costs of nuclear... -
Rob Honeycutt at 10:45 AM on 1 December 2010Renewable Baseload Energy
As if right on cue Steven Chu spoke yesterday at the National Press Club. Dr Chu states that China is investing aggressively in renewables and expects to be drawing 20% of their electricity from renewables by 2020. Peter Sinclair posted an abbreviated version of his talk here. Or there is a full length video of his speech here. -
Daniel Bailey at 10:44 AM on 1 December 2010A basic overview of Antarctic ice
Re Billhunter (62) What part of: "In Antarctica, sea ice grows quite extensively during winter but nearly completely melts away during the summer" Do you not understand? The point of the post is that focusing on Antarctic Sea Ice (ASI) is a strawman argument. ASI offers little contribution to the global energy budget, unlike changes in Arctic Sea Ice cover."Even if we limit the argument to sea ice we can see that indeed it is gaining sea ice. "
Which then melts away come Antarctic summer. The Yooper -
Billhunter at 10:31 AM on 1 December 2010A basic overview of Antarctic ice
Your argument is strange. When one looks at the graphs you provide a good amount of sea ice remains in the southern summer, yet your argument turns on sea ice not melting in the summer thus providing no feedback. Sea ice not melting in the southern summer is patently false and can be seen clearly in your own graphics. Now perhaps when and if the antarctic actually does melt to the edge of the continent a month or two earlier than normal your argument will carry some weight. But for the moment it doesn't seem to explain what it purports to explain is some alleged oversight in skeptic arguments that Antarctica is gaining ice. Even if we limit the argument to sea ice we can see that indeed it is gaining sea ice. -
SNRatio at 10:28 AM on 1 December 2010Renewable Baseload Energy
#178, #179 I don't think base load is a precisely defined quantity - it is dependent on the energy system, energy use and incentives/price structures. If, for example, nighttime power were 10 times as expensive as daytime (think PV-based supply, high CO2-taxes for fossile backup), most persons and businesses would be able to adapt to that. (People charging their electric vehicles at daytime and partly running household applications off battery at nighttime, for example.) Most heating can be buffered, and process industry could have its own supply structure, etc etc. Without rather high-resolution wind data, it is, generally, impossible to give precise estimates of the coverage of a regional wind turbine system, but if a fossile-based generation capacity is already in place, the question will just be how much this backup will be run, not whether a system can be based on renewable energy as one main component. If the main variability is on short (hours) time scales, solar thermal could have a role, biomass could be used for longer time scales. -
Rob Honeycutt at 10:22 AM on 1 December 2010Renewable Baseload Energy
Peter @ 177... I've not read the entire article you linked to but I would suggest that is one case against renewables for baseload. There are obviously huge investor dollars going into renewables right now, and I don't think those dollars are being put in just out of the goodness of people's hearts. They are in this because they think this will be the future of energy generation. Think about it this way: One, we have peak oil either here or coming soon. People can try to wiggle around about that idea and what it means but it's going to affect the future energy mix. Two, at some point climate change is going to become dreadfully obvious to everyone. If we price carbon early it's going be a relatively painless transition. If we put it off, we're still going to have to price carbon but it's going to have to be very aggressive and very painful. There is just no getting around it. Eventually we are going to end up with a carbon free baseload. A large part of that may be nuclear. But I would certainly bet a % of my investment dollars that a sufficient chuck of that baseload is going to be renewables as well. -
Paul D at 10:15 AM on 1 December 2010Solving Global Warming - Not Easy, But Not Too Hard
Not what a lot of skeptics would expect (or want to hear): http://www.bbc.co.uk/news/science-environment-11881663 CBI (Confederation of British Industry) supportive of carbon counting and most companies say it is beneficial. -
HumanityRules at 10:03 AM on 1 December 2010A basic overview of Antarctic ice
59 Phila I think if I made those sort of accusations about climate scientists that you make about "skeptics" my post would be deleted. I see no comspiracy and don't suffer from nihilism. What I see is data and interpretations that are put forward by Velicogna for critical analysis. That's the way normal science works. Rather than trying to get to the heart of "skeptics" mental state why not try looking at the data critically. You can make a much better defence of the data by doing that. -
HumanityRules at 09:55 AM on 1 December 2010A basic overview of Antarctic ice
56 Albatross Albatross thanks for recognizing I tried hard with that analysis. The one thing I didn't do is insinuate anything or suggest anything nefarious. I did think about doing that but tried to stick with John's comment policy and stick to a critique of the authors results. I think we all know that a difficulty with describing rates of change from very short data sets is that variability can lead to very different trends depending on where you start and stop your analysis. I don't really know why I'm describing this to you because I know you have the skill set to appreciate this very basic point already. Please ignore my data presentation, it was only intended to illustrate my points but know I see it's just a distraction. Look at the Velicogna graph (red x's) I show in #55. Tell me around 2006 there isn't a short term slowdown and reverse in the trend. Tell me that if you start and end analysis then that this won't affect the value of your rates. Please tell me the slope of the data is signficantly different before (2003-2005) and after (2007-2009) this 2006 blip. This can all be done by just eyeballing Velicogna's graph, remember she is suggesting rates of ice mass loss have more than doubled over this time period. Do you see that? The conclusions in the Velicogna paper should stand on their on feet irrespective of what other authors have published, I'm really happy to look at the quality of those other results but I relly think if you are going to defend what Velicogna writes then do it based on the merits of her methods not on what others have done. Look I would turn your own comment back onto you in relation to looking at the quality of Velicogna's interpretation of this data. "Really, the lengths some people will go to to convince themselves that there is not a problem." -
Renewable Baseload Energy
Peter Lang - You might want to look at the link Alexandre posted, noting low and even negative correlation between power available when generating stations are widely enough separated. This includes a fairly detailed case study for Europe. It's worth noting that the correlation between windmills separated by as few as couple hundred meters show extremely low values over the <1 minute scale, and proper site selection around Europe shows negative correlation sufficient to handle even seasonal irregularities without a dropout - thus supplying baseline power. I don't know if the same analysis would apply to Australia (due to area and local variations - that would take a sufficiently detailed wind/solar survey), but it would be interesting to look into. You had complained about intermittent power at a particular wind farm - but sufficiently separated wind farms mixed with sufficiently separated solar farms might be quite capable of complete baseline power for Australia too. Yes, long distance DC lines and power storage are important requirements for renewables. But if we have sufficient power and low correlation between sites, your concerns about huge natural gas burners for backup essentially go away. Power storage for short term variations is required for coal and nuclear too - they simply don't ramp up/down fast enough for those variations. If you wish to go on about nuclear (as opposed to the renewables discussed here), I would suggest directing people to the threads where that conversation has already taken place - no need to repeat it here. -
SNRatio at 09:44 AM on 1 December 2010Renewable Baseload Energy
I think it is important to differentiate between investment and operating costs. With sufficiently high calculation interest rate, any sustainable project can be made "too expensive", and with sufficiently low rate, a lot of impractical projects may become "profitable". Because this rate is so essential to all calculations, I tend to distrust purely theoretical analyses. To me, it is much more important what kind of track record the different systems have. So far, it seems to me that renewable technologies are more expensive to implement, but I don't know if the operating costs always have to be that high. I think we need quite a lot of operation data for full-scale systems to make safe judgments. Experience from Scandinavia, where Denmark has a very high coverage of wind power, Sweden has started utilizing biomass for energy production on a large scale (in an ecologically rather safe manner), and Norway traditionally has ca 50% coverage of _total_ energy consumption from hydroelectric power, indicates that sustainability doesn't necessarily come at extremely high costs. -
Peter Lang at 09:26 AM on 1 December 2010Renewable Baseload Energy
I've only just spotted this thread and haven't been following it. Others may have already posted this link to "The Case for Baseload": http://www.eei.org/magazine/EEI%20Electric%20Perspectives%20Article%20Listing/2010-09-01-BASELOAD.pdf This explains why the concept of baseload is rock solid and intermittent renewables cannot meet the requirements. Baseload comprises over 75% of our electricity demand and generation in Australia. It cannot be ignored. David Mills, Mark Diesnedorf, Mark Jacobson and many other renewable energy advocates have been arguing for over 20 years that solar and wind power can meet our needs for reliable power. It is just not true. This is also an excellent article pointing out the reality of how much intermittent renewable energy generation can be accommodated in the grid. Rupert Soames Speach to Scottish Parliament, 12 November 2010: http://www.aggreko.com/media-centre/press-releases/speech-to-scottish-parliament.aspx There is reality and there is wishful thinking. We've had 40 years of anti-nuclear protesting and 30 years of renewable energy advocacy and wishful thinking. It is time for some reality. -
philipm at 09:05 AM on 1 December 2010Greenland ice mass loss after the 2010 summer
There is no fixed concept of how many data points you need for statistical significance. When you try to relate two data sets where you have reason to believe one is causally related to the other, you need to use two measures:- strength of the relationship, measured by correlation
- significance of the relationship, measured by the t-test of the correlation
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2nd law of thermodynamics contradicts greenhouse theory
damorbel - Also, you're incorrect in your statement about equilibrium temperature being unconnected to albedo. Even a simple climate model indicates about a 1°C temperature change for 3.3% change in albedo, 1.4% change in solar constant, or 1.4% in emissivity (for independent changes of a single value). -
2nd law of thermodynamics contradicts greenhouse theory
damorbel - You are incorrect when you state that IR from the Earth without GHG's (at current temperatures) would be anything but 396 W/m^2. -
2nd law of thermodynamics contradicts greenhouse theory
Emissivity of the ground is in the range of 0.96 to 0.99, with cloud albedo at 0.5 accounting for a combined emissivity (relative to a blackbody) of ~0.612. An effective emissivity change of 1.4% (from that same link, with a very simple climate model) will result in a 1°C temperature change. And greenhouse gases directly affect the emissivity of the Earth. As to your "helium atmosphere", total removal of greenhouse gases is a Gedankenexperiment. It's not intended to fully determine an end state, but rather serve as an illustration of how changing a parameter would cause a change from the current state, thus illustrating the importance of that parameter. Arguing about the endpoint of a Gedankenexperiment is quite simply a red herring. -
damorbel at 08:37 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #230 KR You write:- "Actually, damorbel, the surface IR emissions are measured observational data, as are the downward back-radiation numbers. You are quite simply incorrect." Measured or not, the net radiation is from the surface to the atmosphere, is that what you mean when you say "You are quite simply incorrect."? -
damorbel at 08:33 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #227 KR You write:- "Without greenhouse gases to radiate from the upper atmosphere, the 17 convection and 80 evaporative W/m^2 would quickly saturate and cycle back to the ground, reducing net" This is not very sensible, is it? How can you write about "absence of GHGs" and "80 evaporative W/m^2" in the same breath - so to speak? The "80 evaporative W/m^2" comes from the oceans, you know! A completely passive atmosphere, let us say helium (and no water), would still have a temperature gradient due to compression by gravity and it would still circulate heat from the tropics to the poles, it may not be so efficient as water vapour and there would be no liquid water to perform the same circulation but a helium atmosphere would not be some sort of passive participant. -
2nd law of thermodynamics contradicts greenhouse theory
Actually, damorbel, the surface IR emissions are measured observational data, as are the downward back-radiation numbers. You are quite simply incorrect. And greenhouse gases still reduce emissivity to space, sending just under 50% of the Earth emissions back down rather than to space. -
2nd law of thermodynamics contradicts greenhouse theory
Here's an analogy to the greenhouse effect, that incorporates a few critical items: Imagine a reservoir behind a dam. There is a constant stream running into the dam (solar input), output pipes at the bottom of the dam (size = Earth area), with some fractional screens (emissivity) over them. Outflow rate is determined by area of the pipes, screen blockage, and primarily by water pressure/reservoir depth (temperature), which for the sake of discussion will scale with depth^4th. Flow = screen * constant * Area * depth^4 We'll start with the reservoir at a level where water pressure pushes an output flow through the pipes and screens equal to the amount coming in from the stream. Leaves block parts of the output screens (greenhouse gases), reducing output flow (cooling energy flow to space). The leaves increase the back-pressure at the output pipes (back-radiation). What happens? Well, output flow is now lower than input flow, and the reservoir level rises until increased pressure makes output flow equal to input again (temperature rises). That, in a nutshell, describes the greenhouse gas effect. -
damorbel at 08:22 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #223 bis KR You write:- "the surface of the Earth at current temperatures would still radiate upwards to space at net 356 W/m^2," I have done detective work on this and it is based on "the Earth emitting like a black body", yet another piece of GHE folklore that has no foundation. It is very obvious that the Earth is not a black body radiator at any wavelength. A blackbody radiator would have an emissivity (e) of 1, whereas the Earth has an emissivity of 1-a, where 'a' is the albedo. Thus the Earth's emisivity is about 0.7, giving an equilibrium temperature of about 279K Yet another shocker for you to think about, the Earth's equilibrium temperature (279K) is completely independent from the albedo! In support of this you can look at the Trenberth diagram where you will find that the total power absorbed by the Earth from incoming Sunlight is 161+78 = 239W/m2, the same as the total outgoing 239W/m2 - even with a surface temperature of 288K! Pure blackbody radiators do not exist, they are a hypothetical concept introduced to distinguish absorption from reflection (or scattering - to use a better term). -
2nd law of thermodynamics contradicts greenhouse theory
damorbel - Without greenhouse gases to radiate from the upper atmosphere, the 17 convection and 80 evaporative W/m^2 would quickly saturate and cycle back to the ground, reducing net transport to space via those pathways to zero, as it would have nowhere to go - the 169 emission from the atmosphere would be zilch without GHG's. And the 396 W/m^2 IR would go straight into space, rather than the 239 W/m^2 currently. Net would be 156-157 W/m^2 imbalance towards space, as opposed to the current 1 W/m^2 imbalance towards the ground. What do you think - would a negative balance of 156 W/m^2 have (as you seem to claim) no effect, or would it rather cool the earth about 150x faster than it's currently warming? -
damorbel at 07:43 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #223 KR You write:- "So, without the 333 W/m^2 backradiation, the surface of the Earth at current temperatures would still radiate upwards to space at net 356 W/m^2, not net 26 W/m^2. Don't you think this would have a cooling effect?" The real cooling effect of radiation is the 239W/m^2 leaving the top of Trenberth's diagram for deep space. The net 26W/m^2 due to GHGs is trivial in comparison with the 175W/m^2 total contributed by the sun (78W/m^2), water vapour (80W/m^2) and convection (17W/m^2). -
scaddenp at 07:36 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
Other have covered some of your points BUT "Heat transfer by radiation can only be from a hot body (gas etc.) to a cooler, no different from conduction diffusion or convection. " Missing word in here is NET heat transfer. Energy is transferred from cold to hot - a photon isnt magically not absorbed because the absorption surface is hotter than its source. The energy warming from surface of earth is from sun, the ghg are merely backscattering outgoing radiation.Moderator Response: Sorry to nag, but please refrain from using all caps. -
muoncounter at 07:23 AM on 1 December 2010It's the sun
#733: "you should be comparing the daily maximum temperature with the daily minimum " Yes. See the post here. -
damorbel at 07:23 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #221 CBDunkerson You write:- "How does sunlight hit gas molecules in the stratosphere, which is very cold, and then continue from there down to the troposphere, which is much warmer? Your argument would make this impossible... yet it obviously happens. Sunlight travels from a cold region of the atmosphere to a warmer one... indisputable fact." When sunlight hits the atmosphere the UV component at 200 microns and below splits the O2 molecules into two O atoms which then join other O2 molecules to form ozone - O3 O3 further absorbs UV at 300 microns and shorter, thus the sunlight proceeds to the surface shorn of its dangerous UV. But what do you mean when you write this:- "Sunlight travels from a cold region of the atmosphere to a warmer one... indisputable fact."? The sunlight that passes through the atmosphere is not affected by it. The absorbed UV heats the stratosphere and generates the Ozone layer. The heating by UV causes a massive temperature inversion which makes the stratosphere very calm in comparison with the troposphere. Oh, and the temperature at the stratopause is not that low, just about freezing, 0C. -
2nd law of thermodynamics contradicts greenhouse theory
damorbel - Aha, I think I see the issue you're having. Without greenhouse gases, the atmosphere would not emit much IR at all - nitrogen and oxygen don't have the structure to emit in the thermal IR bands. So, without the 333 W/m^2 backradiation, the surface of the Earth at current temperatures would still radiate upwards to space at net 356 W/m^2, not net 26 W/m^2. Don't you think this would have a cooling effect? If greenhouse gases were to go away the Earth would rapidly cool towards -18C, where outgoing top of atmosphere IR would be in balance with incoming solar energy, rather than the current +14C average temperature. Of course, that would lead to glaciation, increasing albedo, and reducing the temperature even further - the -18C thought experiment is just a first pass example. Backradiation greatly reduces cooling efficiency of the Earth - it has to be hotter to remain in energy balance with the sun. Backradiation doesn't have to exceed surface radiation in order to change the net heat loss, which you yourself have shown. The whole issue of backradiation and thermal balance is still based upon energy coming in from the sun, net energy flow to space, and the temperature of the Earth. Reduce the net cooling energy flow to space (reduced emissivity from GHG's), and the system is imbalanced until the temperature rises to compensate. I've pointed you to the very straightforward Thermal Radiation writeup on this, and the governing equation P = e * s * A * T^4. To put it bluntly, if you don't understand that, I don't think I can help you. -
kdfv at 07:10 AM on 1 December 2010It's the sun
Far be it for me a mere mortal to criticise scientists but if you are looking for the effects of CO2 on heat retention you should be comparing the daily maximum temperature with the daily minimum and compare one year another. i.e the daily heat loss. If the rise in temperature is due to the sun then the days maximum will be high but the amount of heat lost over the night will be constant. If it's due to CO2 then less heat will be lost at night. -
damorbel at 06:56 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #218 KR You write:- "greenhouse gases reduce cooling of the surface, which has the result of the Earth's surface heating up in order to radiate in balance with the incoming solar energy." And:- "The observed backradiation from lower atmosphere GHG's is part of the energy balance, which Trenberth listed in his 2009 paper" And crucially:- "except for your somehow deciding that backradiation doesn't have a role" Back radiation would have a role in raising raising the surface temperature if it exceeded the output from other sources. But Trenberth himself has back radiation at 333W/m^2 and the surface sourcing 356W/m^2 to the atmosphere, thus the net upward radiation to the atmosphere is just 26W/m^2 and since it 'is net upward radiation' it is cooling the surface, not heating it! Trenberth has a total of 198W/m^2 going into the atmosphere and 169W/m^2 plus 30W/m^2 = 199W/m^2 leaving to deep space; leaving 1W/m^2 to raise the temperature of the surface by 30K. I may have got some of the figures wrong but without any temperatures on the diagrams it is quite impossible to make any check of the claimed warming effect, so without any question it is a scientifically unsound explanation, I have no idea how you manage to have such faith in it. -
dhogaza at 06:45 AM on 1 December 2010Climategate: Impeding Information Requests?
"Yeah, it will be another "whitewash", eh? :)" That probably reads as though I'm suggesting Mikel will claim it's a whitewash, which wasn't my intent. I'm just pointing out the certainty that the usual suspects in the denialsphere will call any conclusion short of felonies carrying long terms of imprisonment a "whitewash". -
Phila at 06:36 AM on 1 December 2010A basic overview of Antarctic ice
Albatross: Really, the lengths some people will go to to convince themselves that there is not a problem. Or to be more precise, that the problem is with most of the world's scientists. I think the conspiratorial worldview and epistemological nihilism that informs the thinking of most "skeptics" is at least as bleak and alarming as AGW. It's kind of amazing that they find it within themselves to accuse anyone else of pessimism. -
Rob Honeycutt at 06:21 AM on 1 December 2010Renewable Baseload Energy
Kevin @ 162... Bear in mind there are two ways to look at the cost of base load. One with carbon pricing and one without. People can cover their eyes to the future costs of continued CO2 emissions and get one answer. Or, people can grit their teeth, open their eyes and start looking seriously at what the costs of business as usual are going to be. Each of these will result in vastly different economics for the cost of base load power. Either way the costs are there. One priced into energy. One priced into society.
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