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Marcus at 22:03 PM on 20 March 2011One of the best climate change ads I've seen
As JMurphy says-so you'd be OK with the Chinese withdrawing *all* investment from the US economy? If you do, then say good-bye to the US economy altogether. Secondly, does this support for energy sources that aren't dependent on foreign dictatorships also extend to *oil*, which comes largely from the most non-democratic nations in the World (like Saudi Arabia & the United Arab Emirates). Seems like you're cherry picking in order to create a straw-man argument, which is pretty much all you ever do. -
JMurphy at 21:52 PM on 20 March 2011One of the best climate change ads I've seen
Berényi Péter, does your aversion to Chinese investment extend to all of it or just that bit invested in renewables ? -
John Brookes at 21:43 PM on 20 March 2011Sea level rise: coming to a place near you
That wasn't a wise man, it was Bob Dylan! -
Berényi Péter at 20:34 PM on 20 March 2011One of the best climate change ads I've seen
#11 Marcus at 16:15 PM on 20 March, 2011 The second part of your argument is just naked racism I see. If one prefers a constitution based on checks and balances in order to secure the Blessings of Liberty to one built on people's democratic dictatorship and the principle of democratic centralism, that's naked racism. I have not heard this line of argument in more than two decades but I can't say it is unheard of. In fact I was fed this BS ad nauseam during my youth. -
R. Gates at 17:26 PM on 20 March 2011Zero Carbon Australia: We can do it
While I appreciate the optimism and logic you display in your article, from what I can see going on politically in the U.S. and elsewhere, I think the momentum for making serious changes has slowed to a near stand-still and in some respects reversed. To make the kinds of changes you suggest will require a different mind-set of the majority of citizens-- something akin to a "war footing" and that is not currently in place. It will only be to the extent that climate change related "inconveniences" impact the lives of the average person that they get a war-footing mentality and support the kinds of changes suggested. In short, even if the majority of politicians were behind what you suggest (which they aren't), they'd still need to convince the majority of voters to go along with these changes as their will be the upfront costs. -
Rob Painting at 16:36 PM on 20 March 2011Examining the impacts of ocean acidification
Gary Thompson @ 45 - Eye-balling the graph does indeed tend to convey similar pH levels to present during past interglacials, however that isn't the case. The graph simply lacks sufficient detail. Here's what the authors from Pelejero 2010 have to say: "The current human-induced perturbation of seawater pH starts at the low end of glacial–interglacial pH variability. From this perspective, and given that the surface oceans have already acidified by 0.1 pH units since the pre-industrial period, current conditions are already more extreme than those experienced by the oceans during glacial–interglacial cycles (Figure 2). Moreover, by the end of the twenty-first century, the projected decline in seawater pH might be three- times larger than perturbations observed as the Earth’s climate has oscillated between glacial and interglacial periods" Note that the 0.1 units referred to by the authors, represents almost a 30% increase in acidity over pre-industrial levels. Atmospheric CO2 (as contained in the ice cores) is a proxy for global ocean pH because of Henry's Law. More CO2 in the atmosphere dissolves into the oceans as concentrations in the atmosphere rise, causing pH to fall. (See the equations in the above post) . As atmospheric concentrations of CO2 fall (as in entering into a glacial period), CO2 dissolved in the oceans decline raising pH. The chemical reactions move in the other direction. Of course the ice cores only go back 800,000 years, and that's where the boron isotopes come into play as a paleo pH proxy. So your question as posed, is invalid. As stated earlier ocean pH levels have not been this low for millions of years. Here's what Pelejero 2010 have to say on that: "The average surface pH levels that oceans have reached today are already more extreme than those experienced by the oceans during the glacial–interglacial changes and beyond, probably being more extreme than at any time during the last 20 million years" Read the study, it summarizes the subject very well. -
Marcus at 16:17 PM on 20 March 2011One of the best climate change ads I've seen
Also, BP, though its true this doesn't represent peer-review science, it is *backed* by the vast bulk of peer-review science. Meanwhile, the propaganda being pushed out to the public, by the Contrarians, isn't backed by peer-reviewed science, but I bet you don't object to that-even when its funded by tax dollars? -
Marcus at 16:15 PM on 20 March 2011One of the best climate change ads I've seen
Yes, Beranyi, & how much tax-payers money do you think the US Coal & Nuclear industries get-in spite of being "mature" technology? Lets just say that it is way, way more than $450 million. So you're really just putting up a straw-man argument right there. The second part of your argument is just naked racism, which I'm sure you'd hate were it directed towards you. I see that, after months of posting bogus arguments, you're finally just scraping the bottom of the barrel. -
Marcus at 16:06 PM on 20 March 2011Zero Carbon Australia: We can do it
I think there's something we need to ask in relation to the title of this post-how are we defining "Zero Carbon"? I mean, are we talking net zero CO2 (i.e. where the amount of CO2 put out is at least matched by the CO2 soaked up by new & existing sinks), gross zero CO2 (i.e. no CO2 emitted from Human Sources at all), or net/gross CO2e (i.e. where the amount of *actual* CO2 produced is offset by a reduction in the production of other, worse, greenhouse gases). If its defined as net CO2e, then I think Bio-gas is an oft overlooked option for base-load energy production. After all, human waste streams are *always* going to produce methane, which is an 8 times worse GHG than CO2. So every tonne of methane converted to a tonne of CO2 means 7 tonnes of CO2e effectively saved (at least as I understand it). Also, every tonne of CO2 produced from burning bio-gas to generate around 2 MW-h of electricity saves around 2t of CO2 produced by burning coal to generate the same amount of electricity. So, unless I misunderstand it, burning 1t of methane to generate around 2 MW-h of electricity saves approximately 9t CO2e. Of course, this benefit can be extended further by (a) using any waste heat to heat local buildings or heat for industrial uses & (b) if the bulk of the CO2 gets captured in algal biomass, which can then be gasified & re-used to produce electricity/heat. Anyway, just a thought. -
garythompson at 15:52 PM on 20 March 2011Examining the impacts of ocean acidification
It is without question that the atmospheric CO2 now is much greater than prior interglacials. But the ocean pH now is very similar to the pH in past interglacials (about 120,000 years ago) as shown by the graph below which was taken from the pelejero paper. So my question was regarding what was the impact on oceanic species and the possible extinction as related to now. And the fact that the pH in past interglacials was equal to the pH now seems to point to something else that changed the pH since the atmospheric CO2 now is much greater than in the past. -
HuggyPopsBear at 15:30 PM on 20 March 2011Zero Carbon Australia: We can do it
Thanks -
Daniel Bailey at 15:26 PM on 20 March 2011And so castles made of sand fall in the sea, eventually
Apologies for being away: Had to deal with this crazy thing called life, the universe & everything. Charlie A, I'm sorry if you have taken exception to my phraseology. I apologize for a lack of clarity in my thoughts. While indeed in the historical, paleo, record coral atolls have managed (with mixed success) to survive periods of sea level variability, for the majority of those periods the rates of change will be exceeded by those to come. For your observation about land reclaimed from the sea or created out of whole cloth: point taken. I would submit that the areas reclaimed have been quite small in comparison to the existing land surface, however. And that rates of people creation have vastly exceeded those of land area creation. I would also point out that reclamation of areas/land creation is an expensive proposition in an era of stable sea levels; given 1-5+ meters SLR projected to possibly occur over the next 100 years it would seem likely that efforts will shift to protecting as much as possible of what exists via sea walls and tide surge barriers. Given a 5 meter SLR and a 5 meter storm surge, how much can be protected before the cost of protection becomes economically unviable? Napoleon once faced such as onslaught...and fared non-too-well. The Yooper -
Rob Painting at 14:42 PM on 20 March 2011And so castles made of sand fall in the sea, eventually
CharlieA - "It makes the basic point I was trying to make, that there is indeed creation of new real estate going on in many areas" OK. Point taken. -
Rob Painting at 14:36 PM on 20 March 2011Sea level rise: coming to a place near you
Charlie A -"Corals don't grow very fast if submerged more than a few 10's of meters. The existence of coral atolls through the many past changes in sea level are a testament to the resiliency of the coral atoll systems." It's very likely Dan Bailey is correct and the Maldives will be submerged in the future. Like Pacific atolls, the Maldives were subjected to higher than present sea levels earlier in the Holocene. See Kench 2008. Accordingly these atolls too will have solid reef flats that formed during this period of higher sea level. These serve to protect them from long-term sediment loss. However once the reef flats are submerged by the rising high tide, the coral rubble, sediment and thin soils which have accumulated, will be subject to wave damage. Add ocean acidification & coral bleaching into the mix and the future looks a bit dicey. It's a fallacy that atolls, as they now appear, have existed for a long time. They only began forming once the rising sea level, coming out of the last glacial maximum, submerged the atoll summits which formed during the previous interglacial. Something Darwin was unaware of when he first proposed his reef formation hypothesis. -
Charlie A at 14:22 PM on 20 March 2011And so castles made of sand fall in the sea, eventually
#27 Rob Painting. I agree with the above post. It makes the basic point I was trying to make, that there is indeed creation of new real estate going on in many areas. This sequence of several back and forth comments all go back to comment #16 by Skeptical Scientist author Dan Baily, where he stated that "Creation of new real estate (at all, let alone that above future SLR) = slim to none (outside of new volcanic islands)." and my response in #19 that said his statement was contrary to the historical record for coral atolls, the historical growth in seashore land area in urban areas, and the historical growth of some deltas. I didn't think that was a particularly controversial statement, although it drew an immediate contrary response from you. Unless you want to challenge that portion of my assertion that is most relevant to this article ... which is that almost all urban areas have added real estate over the last 100 or 200 years, even as the sea level continued to rise; then this exchange has reached its end. -
Marcus at 14:12 PM on 20 March 2011Zero Carbon Australia: We can do it
Tom @28. I've read about a number of low-carbon building techniques over the years-in a purely amateur fashion of course. Like I said, the Romans made their cement out of Aluminium Silicate-which was to be found in abundance on at areas of high volcanic activity. Ironically, fly-ash waste from burning coal is also a rich source of aluminium silicate as well (& there must be *billions* of tonnes of the stuff buried around the world after at least 30 years of the stuff being collected in flue stacks, rather than released into the atmosphere). Anyway, the stuff we've been using since the 19th century makes use of Calcium Carbonate which, when baked at high temperature, releases CO2 & leaves behind Calcium Oxide-which is what they actually use to make the cement. Aluminium Silicate, by contrast, releases no CO2 when it is made into cement-so is effectively CO2 free. Another area is steel manufacture. It's just common sense that steel containing a large amount of material from recycled material will require less energy to manufacture than making it from raw iron ore. Arc Furnaces are also more efficient than blast furnaces, requiring just 1/3rd of the energy to melt iron & steel than blast furnaces. Also, I've read of attempts by the some steel manufacturers to capture the waste heat from making steel, & converting it into electricity (so-called co-generation). All combined, this could make the manufacture of renewable energy generation systems much less CO2 intensive. -
Marcus at 13:52 PM on 20 March 2011Zero Carbon Australia: We can do it
"I was in iceland last year. I saw a BP hydrogen station in Reykjavik (actually I think there are a few of them). Very nice green paints. Unfortunately, not a single car stopping at them. May be some buses stop there from time to time , but I missed the time;" Yes, & how old is this technology Gilles? From my reading its barely been around more than 5 or 6 years. Sheesh, I reckon if I went back in time about 120 years, I'd be able to gleefully "predict" that petroleum & Internal Combustion Engines were a total dead end-because there would have been no petroleum distribution network yet & very few people making use of what little petroleum dispensing centers currently existed at that time. We all know how useful that little prediction would be though, wouldn't we? This highlights how pointless *all* of your questions regarding *current* use of renewable fuels actually is. It doesn't *matter* what the current situation is, as the technology is still relatively new-only the future potential of the technology is what matters. Coal & Oil were, in their beginnings, the only real game in town, yet they took several *decades*, even with 100% government support, to go from the drawing boards to commercial viability-& even today these industries enjoy very healthy subsidies courtesy of tax payers. Yet people like you frequently *demand* that renewable energy technologies be 100% commercially viable, subsidy free, *yesterday*. -
Marcus at 13:41 PM on 20 March 2011Zero Carbon Australia: We can do it
"However, in addition to demand being substantially lower at night (about 40% lower, according to the figures I downloaded), you have to look at how that 7.5hrs of storage is achieved - it's a big insulated tank full of molten salt." A couple of points Bern. Firstly, if the majority of our street lights were solar powered (i.e. powered by batteries charged by sunlight during the day) & if owners of office buildings didn't feel the need to leave the whole office block lit up like a Christmas Tree, then I reckon night-time demand for mains electricity could be cut to little more than 20% of day-time peak demand. Secondly, Molten Storage is great, but I'm surprised there isn't more work going into so-called "Thermo-chemical storage". A number of ubiquitous chemicals-like Methane, sulfur trioxide, ammonia & apparently even water-can be broken down into their constituent components at the temperatures achieved by Concentrated Solar Power (though its true that some require a catalyst as well). Methane can be broken down to CO2 & H2, Sulfur Trioxide can be broken down to SO2 & O2, ammonia can be broken down into N2 & H2 & even water can (with a nickel catalyst) apparently be broken down into H2 & O2. Now, once broken down, the energy can be retained as long as you want, until you re-react them together again-which will, of course, re-release the heat as an exothermic reaction. Not only does it represent an excellent source of long-term storage of solar heat for night time & very cloudy days, but some of the by-products can even be used as feedstock for other industrial processes. Just a thought. -
Marcus at 13:31 PM on 20 March 2011Zero Carbon Australia: We can do it
"if you understand that I'm claiming that it is not worth improving our energy efficiency and save FF, you totally misunderstand me. I'm sorry you're not able to get what I'm really saying - although as a teacher I am somewhat used to this kind of situation." Wow, you're a *teacher*? I really pity your students is all I can say. Every single post you extol the virtues of fossil fuels & tell everyone how civilization can't exist without them. You constantly assert-or at best imply-that energy efficiency is a worthless endeavour-so I'm not sure what there is to misunderstand? Maybe if you want to be better understood, you need to be a more effective communicator of what your actual views are on this subject, because so far you've done an exceptional job of portraying yourself as an unreconstructed supporter of all things fossil fuel. -
cjshaker at 13:01 PM on 20 March 2011We're heading into an ice age
"it looks as though", not "it look as those" Chris Shaker -
cjshaker at 12:59 PM on 20 March 2011We're heading into an ice age
I see the same thing in the graph at the top of this page, we appear to be cooler than the peak during all of the previous interglacials on the graph. Also, it looks as those the temperature has previously been higher during this interglacial, and is slowly cooling overall? The line is quite thick, but it seems to trend down over the past 15,000 years or so. Chris Shaker -
cjshaker at 12:53 PM on 20 March 2011We're heading into an ice age
I am also curious as to whether other people seeing the same things in the graph that I am seeing, ie - is the temperature delta over the 100,000 year glaical cycle 10 to 11 C, as it seems to me? Does someone have a better number for the current temperature than the one provided in that National Geographic article? Chris Shaker -
Bern at 12:51 PM on 20 March 2011Zero Carbon Australia: We can do it
MattJ @ 19: yes, the prototype / pilot plants constructed so far only had 7.5hrs of storage. However, in addition to demand being substantially lower at night (about 40% lower, according to the figures I downloaded), you have to look at how that 7.5hrs of storage is achieved - it's a big insulated tank full of molten salt. You want more storage? Build a bigger tank... Of course, that also requires an increase in the size of the collector to heat it up during the day, but it's not an intractable problem. -
cjshaker at 12:49 PM on 20 March 2011We're heading into an ice age
I'm looking at the graphs again, to see what is really there, instead of what I assume is there. Chris Shaker -
Rob Painting at 12:48 PM on 20 March 2011Examining the impacts of ocean acidification
Gary Thompson @ 43 - CO2 was high in prior intergacials as well as now so I can only assume that the oceans experienced a similar drop in carbonate ions and hence drops in calcification No Gary, you have that wrong. Previous interglacial CO2 levels were much lower than present (no industrial civilization). See ice core graph below: The peak atmospheric CO2 level during past interglacials is generally around 280 - 290 ppm. We are now at 390 ppm. So ocean pH was higher, and less acidic, during the previous interglacials. Thats what the boron isotopes tell us too. Earth has not experienced this level of ocean pH for at least 15 million years. Perhaps longer. See Tripati 2009Moderator Response: [DB] The last time I looked at the ice core data, the peak CO2 levels attained during any interglacial over the past 800,000 years was 298.7 ppm, IIRC. -
Tom Curtis at 11:49 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
LJR 698, I get 3.4249 * 10^-19 Joules per photon myself, and hence four times that energy contained in the box. I have to wonder, however, why are you just feeding the box 1 photon at a time. If the feed rate is 1 photon per second, that represents a temperature of just 0.0016 degrees K, ie, beyond the range of experimental detection. Even if the box is one meter thick so that you are feeding in 299,792,458 photons per second, the temperature of the lid will still only be 0.2 degrees K. That is perfectly fine for a thought experiment, but in that case why not just set the incoming energy as 1 Joule per time unit, and set the time unit as 1/300,000,000 of a second for convenience. For a practical experiment, the values you have chosen are two small to be measurable. -
Sense Seeker at 11:36 AM on 20 March 2011Zero Carbon Australia: We can do it
@MattJ Well, Europe has ambitious plans for renewable energy, but I don't see any JFKs around there. We may not need a Superman to get this done. -
garythompson at 11:27 AM on 20 March 2011Examining the impacts of ocean acidification
Thanks Alan Marshall for the extra details and that helped me with understanding your post better. Also thanks to the yooper in #40 and for the recent paper from Pelejero. This is a very interesting and under reported topic - at least on the web sites I frequent. CO2 was high in prior intergacials as well as now so I can only assume that the oceans experienced a similar drop in carbonate ions and hence drops in calcification. Any idea how current ocean conditions compare with proxy data from the past? My apologies if the answer is in the link provided by the hooper - it's a long paper and I haven't finished yet. -
Rob Painting at 11:12 AM on 20 March 2011And so castles made of sand fall in the sea, eventually
The peer reviewed paper on recent increase in land area of Tuvulu can be found at Webb & Kench 2010 Yes, familiar with the paper. I have no reason to doubt the results of their survey. Seems reasonable to me, we have only seen small rises in sea level thus far. A 2mm average rise in that Pacific region over the last 60 years (although this is higher in recent times) is not enough to inundate the solid reef foundations which formed during a regional sea level highstand there 4-2000 years ago. That's expected to happen mid to late 21st century. Once local high tide overtops the reef flats, the coral rubble and sediments will be subject to wave attack and erosion. See Dickinson 2009. There is a rate of rise for which coral atolls can adapt. Which is variable depending on the ambient conditions. Even before the advent of the industrial revolution many coral reefs drowned when we would have expected them to cope with sea level rise going on at the time. There is, for example, a vast relict reef off the Great Barrier Reef complex. Why did it drown during the Holocene?. We don't yet know. And of course, many reefs back-stepped during the Holocene too. Given all the harm humans are inflicting upon coral reefs, it's unreasonable to expect them to grow to match sea level rise, especially as studies trickle in showing that reef growth is declining around the world. -
L.J. Ryan at 11:03 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
Tom Curtis 697 Part I Working with your model 3 lets assign a starting wavelength of 580 nm at the input which converts to 3.43 e-19 J = A The emissions of < 580 nm via the back wall, radiate through the filter lid. 580 nm and longer are re-radiated via the filter lid. If the physics work as you suppose, the energy is accumulating within the box. The subsequent absorption, radiation and re-radiation will result in equilibrium, whereby 4A = 1.37 e-18 J of accumulated energy. Do you agree? -
Rob Painting at 10:51 AM on 20 March 2011And so castles made of sand fall in the sea, eventually
CharlieA - Are you unfamiliar with the depth of coral/limestone at the typical atoll? Yes, and no doubt so will you, seeing as many of them have not been drilled to the underlying basalt base. The ones that have can indeed be many hundred of meters thick, only the top 10-15 meters being the result of Holocene growth. The coral atolls that have not managed to remain at sea level are generally cases such as the far northwestern Hawaiian Islands Yes, as they migrated into cooler waters. But many reefs "drowned" during the Cretaceous period when they bleached as the atolls were transported into hot tropical waters. And the point you should be taking away from this is that ocean acidification and coral bleaching are going to seriously diminish the ability of coral reefs to keep pace with sea level rise. -
Rob Painting at 10:38 AM on 20 March 2011Maize harvest to shrink under Global Warming
CharlieA @ 53- If the graph in the middle of the post your refer to if Figure 1, then you are incorrect. The figure in the middle of the post is for all areas, not the areas currently under cultivation. Both wrong and clearly doesn't make any sense. I think willful contrarianism is clouding your thinking. Read the study and the caption again. The graph, the one I placed in the middle of the post, is the average growing season temperature for the trials. The trials, quite obviously (but not to you) were carried out in areas already conducive to maize cultivation. Clear enough?. CharlieA -1. Look at your comment #24. The 2nd graph. (D) current maize growing land (% of land area) chart. Please note the the heavy green area in South Africa, just north of Lesotho. 2. Now go to your comment #26 and look at those same areas. Note the blue, indicating INCREASED yield, not decreased? Yes, as my comment at @26 points out, 65% of current maize growing areas decline under managed rain-fed conditions with 1°C of warming, not all areas. And your point is?. -
Tom Curtis at 10:38 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
LJR @696, once the box reaches equilibrium, the amount of energy in each box as radiation is 4 times the energy carried into the box in the time to takes for light to travel from the front to the back of the box (1 time unit). It is two times the amount of energy in an equivalent space above the box one time unit after the box has reached equilibrium. Whether this should be expressed as the box "accumulating" four times or two (or possibly three) times the amount of energy that enters the box in one time unit, I'm not sure. It certainly contains four times the radiant energy entering in one time unit. The third model also contains (and accumulates) an additional amount of energy depending on the thermal capacity of the back and sides, and the lid. Whether the radiant energy accumulated is 4, 3, or 2 times the energy entering the box in one time unit depends on the precise definition of "accumulate" that we us, and as you evidently want to run through this with a ultra-fine tooth comb, we do need to be very precise. Whatever the definition of accumulate we use, however, the facts stated at the start of this post are sufficient to allow any disproof (or proof) of my claims. -
Tom Curtis at 10:22 AM on 20 March 2011Zero Carbon Australia: We can do it
Dana, I was thinking more in terms of alternative forms of concrete that do not release CO2 to the atmosphere as they set; or alternative transport solutions, such as solar powered derigibles instead of passenger ships, or modern automated sail for shipping. Somebody also mentioned non-fossil fuel based plastics and fertilizers. There are a large range of issues in decarbonizing an economy, but only power generation seems to get much discussion. A discussion of other options would be interesting (and very informative to me, so I'm not the one to write it). -
Berényi Péter at 10:09 AM on 20 March 2011One of the best climate change ads I've seen
#9 Tshane3000 at 06:36 AM on 18 March, 2011 Greed is a far easier sell than altruism. Yes. And I didn't know ads are supposed to go under the umbrella term peer reviewed science. However, if we are at icons, this one is right on spot (click on image). Spinning Star Wind Energy Project in Texas gets $450 million (30% of its financing) from U.S. stimulus funds (taxpayers' money), the rest comes from state owned Chinese banks (controlled by CPC, that is). A bargain. -
Rob Honeycutt at 09:37 AM on 20 March 2011The True Cost of Coal Power
Phila... That's a great article. Best I've read in a while. -
L.J. Ryan at 09:37 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
Tom Curtis 695 You said: "By accumulate I mean: A) Once the incoming light starts, it takes more time than the time it takes for light to transit the box twice for equilibrium to be reached; B) If the incoming light is removed, it would take more time than it takes for light to transit the box twice for outgoing energy to cease; and C) The total energy inside the box once equilibrium is reached is greater than the total energy in an equal volume of vacuum immediately above the box through which only the incoming radiation and outgoing radiation transit, ie, there are no extraneous bodies." What about the specific quantifier of accumulate, as stated by you: "5) The accumulated energy in the box in the form of radiation will be four times the energy carried into the box by incoming light in the time it takes for light to travel from the lid to the back of the box." Acceptable or not? -
dana1981 at 09:32 AM on 20 March 2011Zero Carbon Australia: We can do it
Tom #25 - perhaps renewables can't provide baseload power? -
dana1981 at 09:28 AM on 20 March 2011Zero Carbon Australia: We can do it
Rahul #23 - the plan is based on limiting warming to 2C, which is about 450 ppm, but only if every other major emitter follows suit. -
RickG at 09:25 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
damorbel: It is difficult to believe that a diagram showing emission of thermal radiation (W/^m2) can be considered useful when no indication is given of the temperature of the emitting body; why else would the Stefan-Boltzmann equation (E= rhoT^4) be so widely deployed in thermal physics? All I can say is I don't know of a single climatologist on the planet when describing the Earth's Energy Budget, uses anything other than W/m^2. If you are unwilling to accept that simple fact, then I suggest you redo Trenberth's schematic in your terms of temperature and show everyone how it should done. -
Tom Curtis at 09:22 AM on 20 March 2011Zero Carbon Australia: We can do it
Moderators, could we have a thread about zero or low carbon alternatives to fossil fuels. Some of the alternatives here I have never heard of before, and it would be convenient to have a list with references in one location. Also, it would provide a place to send Gilles when he tries to derail a thread. -
Tom Curtis at 09:13 AM on 20 March 2011Zero Carbon Australia: We can do it
Bern @11, one factor that needs to be considered is the impact of clouds on domestic solar photo voltaic cells and solar hot water systems. We have the former at my house, and over the last few months in Brisbane, it has not been very effective. As domestic solar becomes more prevalent, increased cloud cover will see an increase in demand on mains power to run essentials like fridges and computers ;) -
johnd at 08:46 AM on 20 March 2011Maize harvest to shrink under Global Warming
Charlie A at 23:32 PM, my first post on this thread began questioning whether the study told us anything not already known. It appears that the weak point in that statement centres on the word "us", so before the question was addressed I should have defined "us", however I think this thread has done that along the way. For myself, "us" means those people whose understanding is based on what is so readily evident and verifiable in the real natural world, the real physical world. For others, "us" means those to whom the same understanding only becomes real if it has been presented in a peer review study. It's not a matter of the first group ignoring that what the second group depends on, it's a matter of deciding what comes first, getting the job done with the paperwork to follow, or the other way around. This is often a point that defines the perspective of those who are in private enterprise and those who are not. In this particular case, if one wanted to understand how maize responds to changing temperatures, that question was being readily answered in the real world by observing where it is most prolific, and then observing how the growing of it diminishes as conditions change moving away from where they are optimum. If one wanted to know how a 1°C warming or drought conditions affected the crop, that evidence is provided by those who grow the crop under those conditions. If one wanted to know the limits to growing maize, then that will be found by observing where the cultivation ceases. Possibly one of the most authoritative sources as to what that limit is will be any peasant farmer who has avoiding perishing, perhaps merely (significantly?) by growing a different variety. Consider each peasant farmer a source of data. Collectively they yield the most meaningful data of all. It is therefore not dependent on conducting a study to identify those areas that are already beyond where maize is able to be cultivated to discover that if it warms even further that the yield of the non-existent maize will be even less. What would have been of value would be a study tracking the progress of the best of the new varieties being developed by measuring whether they are extending successful cultivation into those more marginal areas or if the pace of new development is failing and the marginal areas are advancing. Only with that knowledge would we be able to make projections into the future. There are two variables involved, the climate, and plant genetics. This study effectively froze plant genetics at a point more than a decade ago. -
Tom Curtis at 08:29 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
LJR @689:"I've already challenged your more simplified models...remember "practical difficulties do not prevent us from exploring theoretical possibilities in ideal cases." And your absurd conclusion of 360 kJ of "boxed" light. Then you walked back your conclusion by saying the light would "decay." post 647"
To start with, that was your simplified model, not mine. Second, I did not "walk back" from my conclusion. I distinguished between the ideal case (3600 kJ accumulated) and every possible practical case (the light would escape or be absorbed by the mirrors before internal storage could be measured or stored). What I was noting was that it would be impossible to set up an experiment that tested your model. In contrast, in each of my models, an experiment could be set up which would be able to test the conclusion (even though they would not match exactly the ideal case) Your inability to master simple reading comprehension is not my problem."Because model three incorporates surfaces with emissivities >0, specifically blackbody surfaces, "accumulated" energy can actually be calculated. Further, because blackbody represents the maximum thermal conversion of all radiation, it also represents the maximum "accumulated" energy of your three models. That is, emissivities <1 absorb less radiation then blackbody therefore "accumulate" less energy...ergo if model 3 is proved to have zero "accumulate" energy models 1&2 also have zero accumulated energy.
By accumulate I mean: A) Once the incoming light starts, it takes more time than the time it takes for light to transit the box twice for equilibrium to be reached; B) If the incoming light is removed, it would take more time than it takes for light to transit the box twice for outgoing energy to cease; and C) The total energy inside the box once equilibrium is reached is greater than the total energy in an equal volume of vacuum immediately above the box through which only the incoming radiation and outgoing radiation transit, ie, there are no extraneous bodies. I believe these stipulations follow from the standard definition of "accumulate", but I believe in your case it is necessary to be precise. Given the above meaning of "accumulate", yes, energy accumulates in all three boxes, and, if you can prove that there is zero accumulated energy in any box, you have proved it in any (as every proposition follows from a contradiction). -
dana1981 at 08:24 AM on 20 March 2011Christy's Unconvincing Congressional Testimony
Citizen - Ben Santer did send a letter to Congress calling out Christy's misuse of Douglass et al. And asking him to defend his associated statements. I don't know if he'll be required to reply. -
damorbel at 08:21 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
Re #668 Ricardo "given that you know how to calculate temperature from the energy flux" I'm afraid I don't; it is temperature calculation that defines the whole 2nd law objection. The 2nd law is about energy transfer and it states that it is a function of two temperatures. To know the rate of energy transfer between two places, as an absolute minimum both the energy source temperature and the energy sink temperature must be known. The sink temperature may be 0K, that is the basis of Stefan's law, it gives the maximum possible energy transfer because no object can have a lower temperature than 0K. If the sink temperature is not 0K the energy transfer is less than the figure given by Stefan's law. If you think of it this way you will see this is the reason why bodies with the same temperature do not exchange energy, neither of them can be an energy source or an energy sink; thermal equilibrium exists! There is another reason why Trenberth's diagram tells us nothing. Yes I noticed that the figures he gives could be derived from Stefan's law, but only if you assume the places he gives as sources, e.g. TOA, act like black bodies. This is simply not possible; the TOA is quite transparent, so it can't possibly meet the definition of a black body. Just having the spectrum of a black body, like a grey body (it's a gas! It doesn't even have that!) is not sufficient to qualify the TOA as a black body; so any figures for enegy transfer in the atmosphere based on Stefan's law will be quite misleading. -
ranyl at 08:18 AM on 20 March 2011Zero Carbon Australia: We can do it
How far above 350ppm does a total zero by 2020 get us? 410-420ppm? "A windmill is made of steel (or carbon fibers) and concrete. How do you produce them without FF (and even dissociation of calcium carbonate produce CO2) ? electricity is transported by copper (or aluminium) wires : how do you produce them without FF ? how do you carry and erect the windmills without FF ? how do you travel across Australia without FF ? how do you power trucks, boats and planes ? how do you make isolators, paints, elastomers, fertilizers ?" (Gilles 2011)post 3. What is possible without FF and at a low carbon cost? -
dana1981 at 08:17 AM on 20 March 2011Zero Carbon Australia: We can do it
MattJ #19 - the study addresses your CST overnight storage concern by noting that overnight demands are low. The 7.5 hour storage estimate is based on daytime power demands. The benefit of CST with storage is that output can easily be ramped down, unlike many traditional sources, which just waste the extra overnight production. Hence the "better than baseload" comment in the article. -
damorbel at 07:35 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
Re My Posts. To those who have noticed:- A number of my posts appear twice, I regret this very much, it is nothing personal but for most of today my attempts to post have failed; I tried the usual rebooting without success. Now I have reinitialised through the home page and see that some these posts now appear more than once; seems to be a glitch somewhere. Rather embarrassing; sorry. -
damorbel at 07:24 AM on 20 March 20112nd law of thermodynamics contradicts greenhouse theory
Re 650 RickG :- "For what Trenberth is demonstrating temperature is neither necessary or relevant in that diagram. I have no problem understanding the diagram myself." It is difficult to believe that a diagram showing emission of thermal radiation (W/^m2) can be considered useful when no indication is given of the temperature of the emitting body; why else would the Stefan-Boltzmann equation (E= rhoT^4) be so widely deployed in thermal physics? You say you 'have no difficulty understanding the diagrams', then it is probably my fault, I must be looking at them the wrong way; would you mind saying just what it is that you understand, please?
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