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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. -
JMurphy at 03:39 AM on 1 December 20102009-2010 winter saw record cold spells
Argus wrote : "You, on the other hand, "do seem to be one of those who like to point out" hot temperature records (no matter how significant or relevant), as if they meant anything. And, at the same time, you like to neglect all cold temperature records (because they don't fit in nicely?)." None of that is true because : The temperature records I point out are significant - check the positions in the records and see how many are in the top 5, but mainly in the top 2. They are also mainly relative to global or regional records. Compare and contrast with your cold records. They are relevant because they are further evidence of a warming world, especially as hot records outstrip cold ones, and have been doing so since at least the 80s - as shown for America here. Cold records have been noted by myself on previous occasions, especially on the other thread I mentioned previously. Cold records are still possible in a warming world (why shouldn't they be ? Are cold days impossible during Summer ?), so there is no assertion by me that they "don't fit in nicely". Argus wrote : "The fact is that 2010 has been a very warm year, with many national records beaten, especially during the summer in the northern hemisphere. Wikipedia lists 14 heat records and no cold ones. Dr. Jeff Masters' WunderBlog lists 17 heat records and only one cold (in Guinea)." Actually, to be more updated, there were NO cold records. And 2010 just joins a long list of record-breaking years and decades. And October also joins the long list of record-breaking months, even under conditions that include a la Nina and an inactive sun. See the relevance again ? Argus wrote : "This is unusual, but how much does one year mean? What do you think? Does one year's weather constitute proof of a change in climate, or does it take several continuous years of records? What if 2011 turns out to be one of the coldest years ever? What will the climate experts say then (my guess is that it would become yet another proof of AGW, somehow)?" Not unusual at all, and when you add it to lots of years (not wanting to base everything on one year, of course), a pattern seems to be developing. And you can't see it yet ? There is nothing stopping 2011 being "one of the coldest years ever". Unlikey but certainly not impossible and certainly not another final nail in the coffin of AGW. For that, you will need..."several continuous years of records" - let's go for 30, shall we ? -
CBDunkerson at 03:33 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
BP, you are arguing (correctly) that not all rectangles are squares. Damorbel is arguing (incorrectly) that not all squares are rectangles. That is... yes, there is such a thing as non-thermal radiation. However, there is NOT such a thing as radiation from a source with no temperature. Two very different arguments. damorbel writes: "EM radiation starts and finishes with matter, it moves at the speed of light and it cannot be stored or otherwise conserved like energy." So... EM radiation is not energy. Fascinating stuff. However, setting that aside... your dodge about the vacuum of space being empty (it isn't) doesn't address the fact that sunlight travels through the Earth's atmosphere. 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. The whole 'broad spectrum' bit was nonsense to begin with because there is no reason a wide range of EM emissions should behave differently than a narrow band... and sunlight shows that it doesn't. There are countless examples of EM radiation traveling from cold areas to warmer ones... and it makes no difference whether it is individual wavelengths vs a wide band or the emissions source is thermal or non-thermal. Examples have been provided of ALL of these behaving the same way... there is no magical 'warmth barrier' to radiation. It's pure nonsense and observably so in the everyday world all around us. -
Albatross at 03:22 AM on 1 December 2010A basic overview of Antarctic ice
Hi Rob @50, The PDF linked in here may be just what we have been looking for. Here it is. -
2nd law of thermodynamics contradicts greenhouse theory
Berényi - Well written post on non-thermal radiation, thank you. Directly inferring temperature from EM spectra only works when the spectra is sufficiently similar to a blackbody curve, whether it has band-gaps or not. Monochromatic and 'cold-light' sources have an inherent energy, but since they are not thermal emitters that doesn't directly correspond to a temperature. However, when you say that "...Earth is a system very far from thermodynamic equilibrium", I would like to point out that as far as we can tell (again from Trenberth 2009, although I'm sure there are slightly different estimates out there) the balance sheet is currently tipped only about 0.9 W/m^2 from dynamic equilibrium. If we can reduce or prevent further GHG emissions, we can reduce that imbalance, and the resulting shift in global temperatures. -
Tom Dayton at 02:58 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
damorbel, imagine there are two stars, named Miami and Anchorage. Both are 100,000 light years from our Sun. From hottest to coolest, Miami > Sun > Anchorage. Miami and Anchorage's radiation emission curves overlap, and intersect at a wavelength W, so the two stars emit the same number of photons having wavelength W. Simultaneously 100,000 years ago, Miami emitted a photon named Sally, and Anchorage emitted a photon named Greg. Sally and Greg both have wavelength W. 100,000 years later, Sally and Greg arrive at our Sun. Our Sun is cooler than Miami but hotter than Anchorage. All physicists in the world agree that both Sally and Greg are absorbed by the Sun. The Sun has no way of knowing that Sally's source was hotter than the Sun, and that Greg's source was cooler than the Sun, because Sally and Greg have the same wavelength W. I believe that in stark contrast you have been claiming that the second law of thermodynamics requires the Sun to absorb Sally but not absorb Greg. Here is a simple question for you: What happens to Greg? -
2nd law of thermodynamics contradicts greenhouse theory
damorbel - As I stated before, 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. The observed backradiation from lower atmosphere GHG's is part of the energy balance, which Trenberth listed in his 2009 paper - it's an energy exchange, part of the balance sheet including incoming solar, outgoing top of atmosphere (which as a point of demarcation is chosen as somewhere above the majority of GHG's), surface IR, back IR, thermals, etc etc. You are obviously familar with EM, heat, energy exchanges, etc. Your description of lapse rates, thermal radiation, etc., seem reasonable, except for your somehow deciding that backradiation doesn't have a role. You have, however, put up repeated strawman and red herring points, such as dying due to lack or H2O in thought experiments, quibbling about monochromatic sources, etc. At this point I consider you to just be objecting for the sake of objecting. If you have actual issues, fine - otherwise I'm leaving this thread. -
Paul Barry at 02:43 AM on 1 December 2010A basic overview of Antarctic ice
@CBDunkerson Thanks for the graph links - very consistent with article. I was merely thinking about showing rather than just telling about the albedo impacts. Come to think of it, it would be nice to have superimposed plots of ice-mass, ice-extent (area) and reflected energy (albedo) altogether - with separations of supported and unsupported ice even if the numbers had to be interpolated or estimated, just to illustrate all of these distinctions in a single picture. -
Albatross at 02:42 AM on 1 December 2010A basic overview of Antarctic ice
Humanity @55, You seem to be trying very hard to make something out of nothing, while at the same time making insinuations about poor science or something nefarious going on. The increase in loss (i.e., slope), over this short time window is indeed there-- but this is part of a longer record showing acceleration in Fig. 2 of Robert's post. I recommend that you redo your analysis, this time using all the data and then finding a model that provides the best fit (linear vs. quadratic). In other words reproduce their results. The answer to your question is the green line in Velicogna's Fig. 2 which you pasted in above. Velicogna's results (accelerated loss of ice)have been confirmed by Chen et al. (2009), Bamber and Riva (2010). Also see work by Rignot et al. (2008)". Again, Fig. 2 in Robert's article provides a nice summary of the bigger picture. Really, the lengths some people will go to to convince themselves that there is not a problem. -
quokka at 02:18 AM on 1 December 2010Renewable Baseload Energy
174 Alexandre The ZCA 2020 purports to be an achievable plan for zero carbon stationary energy using only renewables for Australia to be implemented by 2020. It is founded on spacial smoothing with biomass backup for the solar thermal part. Most importantly it has cost estimates - which are almost certainly very optimistic and time line which is absurdly optimistic. Nevertheless it is quite substantial and well put together. ZCA 2020 You should also read the critiques: http://bravenewclimate.com/2010/08/12/zca2020-critique/ http://bravenewclimate.com/2010/09/09/trainer-zca-2020-critique/ -
Berényi Péter at 01:48 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
#213 CBDunkerson at 00:13 AM on 1 December, 2010 All sources of radiation have a temperature... otherwise they couldn't be sources of radiation. The theoretical 'no temperature' of 0 Kelvin is defined as the point at which matter emits no radiation Which is an oxymoron. damorbel is obviously talking about radiation sources very far from thermal equilibrium. Such systems do not have a unique well defined temperature, yet they may emit radiation. Otherwise how would you explain laser cooling? (Heat never moves spontaneously from a cold place to a hot one, so in a sense laser light has to be cold indeed to be able to cool down things to several nanokelvins.) LED lamp is another example. Or is the common glow-worm (Lampyris noctiluca) hot?
For that matter neither has OLR (Outgoing Longwave Radiation) at TOA (Top of Atmosphere) a well defined blackbody temperature. Partly because Earth is not a blackbody, partly because due to heavy frequency dependence of atmospheric transparency, layers of very different temperature give contributions to OLR. Again, Earth is a system very far from thermodynamic equilibrium.
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damorbel at 01:47 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
Re #213 CBDunkerson you wrote:- "So... 'sunlight'. Which is the broad spectrum of radiation given off by a thermal source known as the Sun. Yet sunlight travels from the cold of space to the warmer upper atmosphere to the warmer still lower atmosphere." Of itself a vacuum contains no material so it can have no temperature, since temperature is a measure of the heat content of molecules and atoms. Electromagnetic (EM) radiation is produced by the vibration (more accurately the acceleration) of electric charge (electrons and protons), so it always is associated with matter how ever far away that matter happens to be. EM radiation starts and finishes with matter, it moves at the speed of light and it cannot be stored or otherwise conserved like energy. Since EM radiation is produced by matter which in turn has a temperature there is a sort of connection between temperature and radiation. But only a connection. If the connection is to be strong the radiation must at least have a spectrum according to the Planck radiation formula. Just having the spectrum is not sufficient, it must have the right intensity also. If the intensity is weakened, say because a star is at a distance then, even though the spectrum remains the same, the temperature is reduced because the intensity is no longer that given by Planck's formula. Further you wrote:- "The important point is that not all sources of radiation have a temperature." Which is an oxymoron. All sources of radiation have a temperature... otherwise they couldn't be sources of radiation." Lasers, radio and television transmitters, microwave ovens are all sources of radiation that does not conform to the Planck spectrum, so the source is not related to matter having a temperature (be careful, the radiation output of a microwave oven etc. is (more or less) independent of its physical temperature). When this 'non-Planckian' radiation is absorbed (by matter) the temperature of the absorbing matter increases - the stored energy is thermal in character, the matter has a temperature. -
Argus at 01:46 AM on 1 December 20102009-2010 winter saw record cold spells
JMurphy, You, on the other hand, "do seem to be one of those who like to point out" hot temperature records (no matter how significant or relevant), as if they meant anything. And, at the same time, you like to neglect all cold temperature records (because they don't fit in nicely?). The fact is that 2010 has been a very warm year, with many national records beaten, especially during the summer in the northern hemisphere. Wikipedia lists 14 heat records and no cold ones. Dr. Jeff Masters' WunderBlog lists 17 heat records and only one cold (in Guinea). This is unusual, but how much does one year mean? What do you think? Does one year's weather constitute proof of a change in climate, or does it take several continuous years of records? What if 2011 turns out to be one of the coldest years ever? What will the climate experts say then (my guess is that it would become yet another proof of AGW, somehow)? As for the suggestion, "Perhaps this should be discussed over on 'Does cold weather disprove global warming?'" - well, I don't know. I have already been directed to this thread once, from another one that wasn't appropriate enough. Perhaps there are too many threads on this site. -
muoncounter at 01:21 AM on 1 December 20102nd law of thermodynamics contradicts greenhouse theory
#206: "GHGs are distributed more or less uniformly up to 80km except for water, by far the dominant GHG, which drops to a low concentration above 15-20km. ... the atmospheric temperature falls steadily with height according to the lapse rate (-6.5K/km), the atmospheric density also falls with height." Multiple sources show CO2 and H2O concentrations vary considerably with altitude. Temperature isn't uniformly decreasing with altitude. Density isn't linear with altitude. #209: "surely these loops do not have a uniform temperature all the way round?" Who suggested that they did? You said 'convection won't work downwards'; most people associate 'convection' with some sort of circulation - including the return trip down. There's no subduction of lithospheric plates without it. "I suggest you put some indication of the temperature distribution on your diagram," The 'heat input' on the bottom and 'fluid cools' at the top would be enough for Wikipedia-level readers to get the point. Apparently you require additional notation? "Isn't it the GHGs that are supposed to cause the GH effect?" Duh; but without solar heat input, there's no surface IR radiation for GHGs to absorb. Deflecting the discussion with these irrelevancies was just tedious some hundred comments ago; now it's pointless clutter, but I suspect that's your actual goal here. -
HumanityRules at 01:15 AM on 1 December 2010A basic overview of Antarctic ice
I wonder if anybody would like to comment on Velicogna 2009? It seems particularly important given that it is one of the most recent and the largest Antarctic estimates in Fig2? I think Robert is picking some of the numbers in his final paragrqaph from it as well. I wonder if anybody could explain the reasoning behind the way she divides up the data? Here is the Antarctic data graph from the original paper.
The data runs from 2002-2009. This is how she describes the early and later rates of ice mass loss in the abstract.
“In Antarctica the mass loss increased from 104 Gt/yr in 2002–2006 to 246 Gt/yr in 2006–2009, i.e., an acceleration of 26 ± 14 Gt/yr2 in 2002–2009.”
Can anybody give me a logic reason why you would separate the time period the way she did i.e. 2002-2006 and 2006-2009? Especially when the Greenland data for the same period is separated to derive rates for 2002-2003 and 2007-2009.
I think I have an explanation. Look at Velicogna fig2 above. Notice the slow down around 2006, you can see it best in the smoothed data (red x's)? You can actually play around with the GRACE data here. I downloaded the data and had a look at the trends and annual changes. In fact if you look at the estimates for ice mass loss on an annual basis then the early years (2003-2005) don’t look so different to the later years (2007-2009). The only way you can generate such large differences in the rate of ice mass loss in Antarctica is by estimating the trends around the year 2006.
Below is the annualised data I generated from GRACE for Antarctica from the POET website (link above). The annualised data is simpler than Velicogna, but you can still see the slow down (actually reverse) in 2006. The units are in sea level equivalents (cm) anomalies and GIA and corrections aren’t removed but this doesn’t matter as it’s the trends that are important and as Velicogna says most corrections are the same throughout the time series. The only varying correction is for atmospherics and this is very small.
Have a play with the data yourself and let me know whether it's the 2006 data only that is giving such large differences in Velicogna's early and late ice mass loss rates.
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JMurphy at 01:02 AM on 1 December 2010A basic overview of Antarctic ice
fydijkstra wrote : "So, the increase of Antarctic sea ice is also antropogenic? This looks like immunization of the AGW-theory. It does not matter which new evidence is found, it always supports the theory. When a theory reaches this stage, there is no need for further research. The billions of dollars can better be used to build dikes in Pakistan." Sounds very similar to creationist views of evolution : So they accept quill knobs as being evidence of feathers when it fits with their evolutionary paradigm, but they reject such reasoning when it overturns their theories. Inconsistent Reasoning Governs Evolutionary Interpretations of Feathered Dinosaurs -
Alexandre at 00:44 AM on 1 December 2010Renewable Baseload Energy
swieder #161 That Kombikraftwerk link is very interesting. Combining different renewable sources seems to smooth the output enough to have a reliable baseload source. The smoothing effect of a continental-wide grid of windmills would be achieved by a country-wide grid of different renewables.
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