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Comments 80201 to 80250:

80201. Stevo at 15:18 PM on 6 July 2011
       History Matters: Carbon Emissions in Context
       daisym @7 Isn't mitigating the effect of sea level rise, ice cap melt, extreme weather events, agricultural losses and population displacement a good enough swag of benefits fow you?
80202. scaddenp at 15:15 PM on 6 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Norman, when you are talking about "cycles", then there needs to be a clear distinction between unforced cycles, which have no external driver, and forced changes. ENSO and thus any downstream influences is example of unforced cycle. The interesting question is whether there is any evidence for unforced cycles with periods longer than 30 years. These are postulated - notably Tsonis and Swanson. However, other supposed "cycles" are more likely forced by variations in TSI and aerosols. On top of that, is the question as to whether warming increases the severity of weather effects within the normal cycles. La Nina's now are warmer than El Nino's of decades past - what does that do to weather? So merely saying that there has been periods of drought,storms, etc in the past is uninteresting. The postulate is that when there are extremes, then these are on average worse/more frequent etc. The most robust prediction would be about severe precipitation events and the Min et al paper, and the papers on flood events in IPCC would both appear to bear that out. I reiterate though that it is consistent with predictions, not "proof". Now 2010 events might indeed be linked to natural cycles but the severity of them is may be increased.
80203. Chris G at 14:42 PM on 6 July 2011
       Glickstein and WUWT's Confusion about Reasoned Skepticism
       Umm, from Watts' paper: "... no matter what CRN class is used, the estimated mean temperature trend for the period 1979-2008 is about 0.32ºC/decade." Did I read that right? That rate is slightly higher than the GISS US surface rate, ~0.30ºC/decade, over the same period. He is co-author of a paper that contradicts one of his main themes, that warming is not really happening? I know this is only US surface station data, and not accounting for lag, or getting too particular about logs, but if he says we are getting 0.32/decade out of ~335 to 380 ppm, would that not put Watts himself in the category of 'warmist'?
80204. Norman at 14:20 PM on 6 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       scaddenp @ 245 "I would say that you are making the hypothesis that there is unforced cycles in the weather pattern and these alone are enough to explain weather. An alternative hypothesis which doesnt require unexplained cycles is to use existing physics and postulate that these are result of global warming." Good point, my objection is that when I go searching for articles on past climate (and I have only hit the tip of the iceberg) I see cycles and no strong evidence (except temperature graphs) that climate (long term weather patterns in a specific region) is shifting to a new more severe pattern because of forcing caused by warming. Here is another example. Most the time I post these I am accused of cherry-picking. It would be a valid point if it was just one article. But when you find numerous articles with much the same evidence, I do not know how the cherry-picking charge remains valid. Precipitation patterns for Mid-Atlanctic region. Look at the graphs. They show cycles. I can get more. Maybe I should just compile 10 or 20 links on one post that show cycles and when going back further in time, the extremes are no longer that disturbing as for some reason this extreme pattern was able to form in a non globally warmed world. At this time I plan on researching Dikran Marsupial's concept that the proof of Global Warming being a driver in extreme weather is the frequency of the extreme events. I have been focused on intensity of events. Next study is to see if the long term historical record indicates extreme patterns are taking place more often than they did in a cooler world.
       Response:

       [DB] "when I go searching for articles on past climate (and I have only hit the tip of the iceberg) I see cycles" and "Look at the graphs.  They show cycles."

       This becomes tiresome.  Seeing "cycles" without proposed physical causatives mechanisms to explain them is little different than numerology/superstition or tilting at windmills. Your preconceptions are blinding you, despite the able help of some of the august contributors to this thread.  Eg., you can't see the forest due to all the trees in your way.

       Please refer back to the OP for this Dr. Masters quote:

       "A warmer planet has more energy to power stronger storms, hotter heat waves, more intense droughts, heavier flooding rains, and record glacier melt that will drive accelerating sea level rise. I expect that by 20 - 30 years from now, extreme weather years like we witnessed in 2010 will become the new normal."

       and this cited by Dr. Masters:

       "those who deny a human-caused impact on weather need to pose a viable mechanism of how the Earth can hold in more energy and the weather not be changed. Think about it."

       Emphasis added (to both quotes); that last bit is good advice. As for this last bit from your comment:

       "I can get more."

       Please don't.  You don't want to accept the premise of the OP, that we may be witnessing the human-caused impacts on weather now, and that extreme conditions of the present may be the new norm in 20-30 years; we get that. 

       But unless you can prove that these extremes currently being experienced are NOT due to human-influence and that you have physics-based hypothesis' supplemented by solid statistical analysis to back up your contentions, then you are just being contrarian and most here will no longer waste any of their valuable time trying to help you gain understanding.

80205. Norman at 14:03 PM on 6 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Dikran Marsupial @ 257 I am wondering what you are getting at by bringing up chaotic systems. Looking at the little animations of the pendulum by DB and Riccardo. Maybe you are pointing out that if you increased the energy of this system (made the pendulum swing faster), the frequency of the various cycles would increase (based upon your point that the return rate is a way to measure extreme events: "Extreme events already have a good statistical definition, namely the return period, for instance an event might have a return period of 100 years, in laymans terms, a "once in a hundred year event". This definition has the advantage of automatically taking into account the skewness of the distribution.") My question, if that is the case, is the 0.8C temp increase and 4% moisture increase of the atmosphere enough of difference to be noticeable? That is the conclusion of Jeff Masters of which this thread is about. He belives the extremes of 2010 and 2011 (not anyone event but the aggregate of all the events) are enough to determine the pendulum is moving faster.
80206. Mark Harrigan at 13:45 PM on 6 July 2011
       Over the tipping point
       I wish Beyond Zero Emissions were realistic - but it isn't, as this critique shows. beyond zero critique Wishful thinking won't solve our problems. We need to confront the realities of renewables not (yet) being ready to provide the full answer and focus on what needs to be done to get them there while we put in place bridging solutions. It would be good to see Mark Diesendorf's plans Baseload renewable plan put to the test somewhere with a "utility" that uses a mix of wind (with intelligent predictive anemometering) and solar thermal supported by gas/biofuel turbines (or similar) to manage the variability Or perhaps there are other variations on this theme? A plan to make a relatively modest investment as a sort of "demonstrator" seems smarter to me than trying to push a whole of industry transformation plan that lacks credibility and won't get support because of entrenched interests and easily attacked heroic assumptions. We need to put up proposals that acknowledge we don't know all the answers and need to find out rather than grand schemes that purport to "fix" the problem.
80207. Norman at 13:44 PM on 6 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Tom Curtis @ 258 I do not think you are correct on this one about severe thunderstorms. I have been checking around for the type of thunderstorms that dominate the ITCZ. I am not sure your lightning proxy is totally valid for detemining the severity of a thunderstorm when dealing with the different kinds (like comparing apples to oranges). No doubt an air-mass thunderstorm with more lightning strokes is more severe than an air-mass thunderstorm with fewer strokes. But it would not be as severe as a super-cell thunderstorm. From article on the ITCZ: "The ITCZ is formed by vertical motion largely appearing as convective activity of thunderstorms driven by solar heating, which effectively draw air in; these are the trade winds.[2]" Article source of above quote. A quote from another article: "Supercells are the most powerful thunderstorms. By their definition, supercells are always severe. Supercells are responsible for a disproportionate amount of damage and casualties." Article source for supercell quote. The air mass storms can be intense for short periods of time but not nearly as long as a supercell. Another quote from above article link: "The air mass thunderstorm is a common and usually non-severe phenomenon that forms away from frontal systems or other synoptic-scale disturbances. They form where moist and unstable conditions exist in the atmosphere. Air mass thunderstorms are usually produced in areas of very little vertical shear. As a result, the threat for severe is small. When they do reach severe limits, the thunderstorms may produce brief high winds or hail which develop because of high instability. These storms are know as pulse severe storms. Although several storm cells can develop, each individual cell lasts about 30-60 minutes and has three stages." Another article on Thunderstroms similar to the others. Article on thunderstorms. And yet another article. Air Mass Thunderstorms are usually weak. From what I was able to find out about thunderstorms, I cannot agree with your concluding statement. "Consequently, every element of "severe" thunderstorms, with the possible exception of tornadoes, is expected to increase globally with a warming climate, though not in all regions. That is, we can expect more damaging winds, more large hail, more flash floods, and more lightning strikes. And tornado frequency is also predicted to increase, though I can't lay out the logic of it the way I can for thunderstorms in general." The following information just about goes opposite of your concluding statement. Most severe storms in US occur in spring and early summer.
80208. sentient at 13:12 PM on 6 July 2011
       The Last Interglacial - An Analogue for the Future?
       Philippe Chantreau I tend to find that speculating on things which have happened is decidedly more comfortable than speculating on things which have not happened yet, as in model speculations. Especially when one is frequently engaged to dig into the opposition's modeling in toxic torts and insurance litigation related to same. Fascinating work, by the way. On Dansgaard-Oeschger oscillations. There were 24 Dansgaard-Oeschger oscillations between this interglacial, the Holocene, the interglacial in which all of human civilization has occurred, and the last one, the Eemian, and yes, we were indeed there as our stone-age selves. D-O oscillations average 1,500 years, and have the same characteristic sawtooth temperature shape that the major ice-age/interglacials do, a sudden, dramatic, reliable, and seemingly unavoidable rise of between 8-10C on average, taking from only a few years to mere decades, then a shaky period of warmth (less than interglacial warmth), followed by a steep descent back into ice age conditions. Each D-O oscillation is slightly colder than the previous one through about seven oscillations; then there is an especially long, cold interval, followed by an especially large, abrupt warming up to 16C (a Bond cycle). During the latter parts of the especially cold intervals, armadas of icebergs are rafted across the North Atlantic (Heinrich events), their passage recorded reliably by the deep ocean sediment cores which capture the telltale signature of these events in dropstones and detritus melted out of them. D-O events may indeed be caused by changes in oceanic circulation. Indeed many workers agree with this paradigm, however it would seem as many suggest other mechanisms, however I tend to agree with Sole, Turiel and Llebot (quoted in my first post) when they conclude "However, a cause for this regular arrangement of cycles, together with a justification on the abruptness of the warming phase, is still absent in the scientific literature.” Then again, Michael Shultz, writing in PALEOCEANOGRAPHY, (VOL. 17, NO. 2, 10.1029/2000PA000571, 2002) states in the abstract "During this interval the spacing of the Dansgaard-Oeschger onsets varied by ±20% around the fundamental 1470-year period and multiples thereof. The pacing seems unaffected by variations in the strength of North Atlantic Deep Water formation, suggesting that the thermohaline circulation was not the primary controlling factor of the pacing period." Which would tend to suggest that not only may we really not know what causes them, but as also quoted in the initial post, T1 exhibits the same characteristic, and we still do not know exactly why the terminations occur. Yet again, we continue to discover that even on things which have happened, the science is not that particularly well settled. Evidence was early presented for the presence of D-O signal within the Holocene, which is best preserved. Bond et al (SCIENCE, VOL. 278, 14 NOVEMBER 1997) (the Bond the cycles were named after)state in their abstract: "Pacings of the Holocene events and of abrupt climate shifts during the last glaciation are statistically the same; together, they make up a series of climate shifts with a cyclicity close to 14706500 years. The Holocene events, therefore, appear to be the most recent manifestation of a pervasive millennial-scale climate cycle operating independently of the glacial-interglacial climate state. Amplification of the cycle during the last glaciation may have been linked to the North Atlantic’s thermohaline circulation." I think you are partially correct in that there is at least a probability that "Whatever else is "naturally happening" according to Sentient is bound to be profoundly affected." so long as we critically examine the term "bound to be". This, by definition, is speculation. Speculation about events which have not happened yet. We have mathematically guessed that it should happen, but that does not mean that it is bound to happen. Though it very well might. The evidence I presented in my first post suggests that at least in the B and C cycles of Sole Turiel and Llebot, "profoundly" does indeed figure in to the precautionary principle calculus.
80209. Dave123 at 12:21 PM on 6 July 2011
       OA not OK part 2: Thermodynamic duo
       Doug, Are you going to use Rustum Roy's work as examples in this for the biological side of things? Anyhow good with the peanuts, but it may not carry the speed or extent to which individual atoms and molecules can move from one side to the other, while the numbers remain constant on each side at equilibrium.
80210. Doug Mackie at 11:56 AM on 6 July 2011
       OA not OK part 2: Thermodynamic duo
       @4JosHag: 1) No simple K for this reaction as calcification is biological and multistep. 2) Yes, calcite and aragonite are different. We cover both of these later. Right now we are just getting a few basics straight.
80211. The Inconvenient Skeptic at 11:43 AM on 6 July 2011
       The Last Interglacial Part Two - Why was it so warm?
       Steve and Chris, Since the answers are related I will address you both. Chris misses the point that the Earth's overall temperature is in phase with the seasons and not in phase with the TSI. That makes the Earth's temperature dependent on the seasons and not the TSI. If the Earth's temperature was in phase with the TSI the warmest temperature would ALWAYS take place within a month of the perihelion. That is not the case. The standard measure of the Earth's temperature is the atmosphere. Chris takes issue the the Southern Ocean and comments on heat capacity, but that high heat capacity simply prevents as much change in temperature. Therefore the Earth is coolest when the SH is in summer even though the Earth as a whole gets the most energy. The data on the Earth being warmest is from the CRU. Hardly a skeptical bastion. That leads back to Steve. If you look at the temperature spike of the Eemian it ramps up to the peak temperature ~128,000 years ago and then dropped as insolation peaked. The main vegetation peak could not have happened that quickly. The forests of the Eemian dwarf those of today. They could not have filled the void that quickly. Far more likely from the reconstructed temperature data is that the vegetation filled in and caused the temperature drop that happened ~126,000 years ago. The question is does the positive (albedo) or the negative (evapotranspiration) dominate. Here is your conundrum. You require a far more complex theory to explain what is simply explained by insolation. 14% extra summer energy is significant in the NH. If insolation is the correct answer, that causes significant problems for your current theory of global warming. Hence you must find an alternate solution and must discard the simple and most probable conclusion. You disregard the current climate data (NH summer causes warmer Earth by 4C) in favor of the far more complex and unprovable solution. The solution is readily available. The Holocene experienced ~10C temperature change with a 50 W/m2 change in 65N insolation. The Eemian experienced a 71 W/m2 change which is ~14C change in temperature. That would also be how much the temperature warmed up in the early Eemian according to the EPICA data. Northern Hemisphere Climate Sensitivity
80212. adelady at 09:56 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       BBD "Realistic projections must reconcile with a sharp increase in overall electricity demand over coming decades as the wholesale electrification of personal, commercial and public transport really gets underway. " I don't see this increase in overall electricity demand as inevitable. In fact, I'd see investment in negawatts expanding in parallel. A home or business building can be its own source of power using the grid as a battery. As long as the structure is progressively improved with more insulation and other retrofits, recharging electric vehicles should not draw more power than is provided - esp if the vehicles' batteries export power when required. A city with several thousand (or tens of thousands) vehicles should have access to a fair amount of power in those batteries. When we're talking about supplying power to established cities and communities, we must always remember that there's a huge benefit in investing in negawatts by upgrading structures for not much outlay. Combining this with import/export of power through a grid connected to other areas which don't suffer simultaneous loss of wind/solar input relieves a lot of the stress on the local system.
80213. Bob Lacatena at 09:40 AM on 6 July 2011
       Antarctica is too cold to lose ice
       5, Steve, I'm not sure what your point is, but it's important to read everything, and not just stop when you find something you like. That's not what I'd call "skeptical." I have a lot more research to do, but after just a few minutes work... First, remember the report was released in 2007, meaning it was based on data compiled before then. In particular, however, the section you linked to includes these words:

       Further accelerations in ice flow of the kind recently observed in some Greenland outlet glaciers and West Antarctic ice streams could increase the ice sheet contributions substantially, but quantitative projections cannot be made with confidence (see Section 10.6.4.2).

       Just a year later, a study found that ice lose in Antarctica was in fact accelerating: Antarctic is losing ice ‘nearly twice as fast as ten years ago’ In addition, I don't know what GRACE data was available at the time. The satellite was only launched in 2002, and some years would be needed to identify a trend -- a very serious and bad trend, it turned out. From NASA's GRACE pages:

       Gravity data collected from space using NASA's Grace satellite show that Antarctica has been losing more than a hundred cubic kilometers (24 cubic miles) of ice each year since 2002. The latest data reveal that Antarctica is losing ice at an accelerating rate, too.

       At the same time, the numbers in the IPCC AR4 report do not seem to have used GRACE data at all (although they could have). They were instead based on models that apparently predicted mass gain in the Antarctic (if we are interpreting that table correctly). But it was based on model runs, and so limited by assumptions made in constructing the models. It would appear that the models then did not take into account what has since been discovered, and explained fairly clearly in the above post. Appendix 10.A: Methods for Sea Level Projections for the 21st Century
80214. BBD at 08:52 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       My views on renewables are shaped by the UK experience. As I said at the outset, the UK chief scientific advisor to DECC provides a rigorous assessment of what this will entail. In 2009, Dieter Helm wrote an article in the Times in which he said:

       Instead of a coherent, integrated policy, we have piecemeal support for particular technologies. Politicians want to be seen to be “doing something” for the various interested parties — especially for renewables and clean coal. So each gets its own set of supports. Take wind. Britain has one of the most expensive support packages in the developed world. Customers have to buy a proportion of energy from renewable sources, paying the usual price and a premium that the Government guarantees. And that has been doubled for offshore wind. The costs are far greater than conventional technologies, and make even nuclear look cheap. If, as a result, overall emissions were cut on a significant scale, it would at least meet the carbon objective. But because the wind does not blow all the time, there has to be back-up — carbon-emitting coal and gas. Next, take clean coal. It too has its own government support. Carbon sequestration (CCS) — storing carbon in the ground — will be subsidised by a new levy on customers — linked to the price of carbon in the European Emissions Trading Scheme. What the customer gets is not, however, just clean coal technology — they will support several large new coal stations, most of which will not have to store carbon emissions until 2025. We need coal now because otherwise we will be too dependent on gas — and to back up the intermittent wind. Now take nuclear. Unlike with wind power, customers are not obliged to buy it, and there is no special subsidy or levy. Nuclear is left to the market, but wind and clean coal are not. The result is a mess, driven by the dangerous combination of the Government choosing the winners and lobbyists trying to capture subsidies. For all the good intentions, the result will be high cost and low impact. Instead of starting with the cheapest ways of reducing carbon emissions, Britain has started with the most expensive. So far success has been limited: We not only pay among the highest bills for wind, but in Europe only Cyprus and Malta generate a lower proportion of their electricity from it. Old nuclear is closing, but new nuclear is unlikely to appear much before 2020, and coal will not come to the rescue any time soon. The result is more gas, and, but for the recession, real risks to the security of supply.

       Helm, like MacKay is serious, and should be taken seriously. I recommend reading the rest - it's short.
80215. Steve Case at 08:49 AM on 6 July 2011
       Antarctica is too cold to lose ice
       Chapter 10 Figure 10.7 in the IPCC's AR4 shows negative numbers across the board for the contribution of the Antarctic Ice sheet to Sea level rise which would indicate that Antarctica is gaining ice. http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-6-5.html All the other numbers in table 10.7 are positive.
80216. JosHagelaars at 08:49 AM on 6 July 2011
       OA not OK part 2: Thermodynamic duo
       @Doug Mackie, I appreciate the topic very much, but I hope you go more in depth later on. What is the value of the dissociation constant (pK) of this calcification reaction ? Is there a difference in pK for the two main forms of calcium carbonate, aragonite and calcite ?
80217. BBD at 08:04 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       JMurphy Perhaps we are losing our way. There is no doubt that nuclear and renewables are all low-emissions generation technologies. Lifecycle emissions profiles are relevant, but not decisive. We can argue all night about the details but what would be the point? I can only remind everyone that the EU is conspicuously committed to emissions reductions and to renewables, and is unlikely to use bad data that misrepresents the relative lifecycle emissions of nuclear, wind and solar plant. Which is why I provided the link to EU documentation. The essential question (as we are reminded by the moderator) is whether or nor renewables can actually deliver reliable large-scale baseload capacity sufficient to meet the needs of an industrialised economy. Realistic projections must reconcile with a sharp increase in overall electricity demand over coming decades as the wholesale electrification of personal, commercial and public transport really gets underway. The shift from gas (and to a lesser extent oil) to electricity for domestic heating is a major factor in the UK. No doubt it will be elsewhere. Here and elsewhere, an energy-hungry surge in urban AC is projected to manage increasingly extreme urban temperatures. And so on. Nothing I have seen on this thread demonstrates a plausible case for high-renewables scenarios as things stand, never mind over decades of increased demand. I wish it were otherwise, but we have to play with the cards on the table.
80218. Rob Painting at 07:55 AM on 6 July 2011
       Great Barrier Reef Part 1: Current Conditions and Human Impacts
       John Bruno - I wonder how those researchers would react in the following situation: Say for instance Sweatman was feeling poorly; stomach cramps, nausea, headaches and a high fever. Off he trundles to the doctor (Bob Carter), who hasn't treated him before and isn't aware of his normal physical condition. Dr Bob Carter diagnoses and prescribes various medications. A week later he hasn't improved at all, so back he goes to the doctor. Dr Bob examines him again and, based on Sweatman's condition in the first visit, finds his condition hasn't deteriorated any further, whereupon he declares "You're in fine fettle Mr Sweatman!" I think that little analogy reflects the absurdity of the claims. And I hope none of your poorly informed colleagues make it into practicing medicine!
80219. BBD at 06:55 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       Moderator #153 I am now even more painfully embarrassed. Link. For the record here: The original head-face gaffe was both careless and unintentional. I fully accept your criticism wrt a poor choice of simile in a sensitive discussion. I apologise unreservedly to TC for the apparent slur.
80220. Tom Curtis at 06:44 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       JMurphy @155, Barry Brook cites a study by Bilek et al which shows whole of fuel cycle emissions for nuclear power as 60 gCO2e/kWh for light water reactors (10-130), and 65 (10-120) for heavy water reactors. The study quotes other studies using comparable methods to show 21 gCO2e/kWh (13 – 40) for wind, and 106 (53 – 217) for photovoltaics. Having now gone through the methodology, I can confirm that Bilek and all do cover all major inputs and make reasonable assumptions and methodological choices, so the 60 gCO2e/kWh looks like a reasonable figure from which to make comparisons. Brook makes the reasonable point "...for fast spectrum reactors like the IFR, it would be substantially lower, since we skip the mining, milling and storage steps", but does not comment on how much lower. Brook does not give a figure for how much lower, but from the report it appears missing those steps would save from 10 to 25% of emissions, giving us emissions of 60 gCO2e/kWh for old reactors, and 45 gCO2e/kWh for generation III and IIIplus reactors. These figures should be reduced for countries with primarily low emission power generation (as, of course, should the equivalent figures for renewable power).
80221. Patrick 027 at 06:32 AM on 6 July 2011
       The Planetary Greenhouse Engine Revisited
       Re Michele - as the results of my simulation show, You're simulation was designed based on your assumptions; it doesn't show those assumptions to be correct. I think that if you continue to argue about the total radiative balance we could leak the true causes leading to actual temperature profiles (GH effect). I and others already did. You refused to accept it. Of course the radiation/evaporation also takes place on the way but it seems to be very tiny as its contribute to the lapse rate seems to be negligible: if it had a real weight the lapse rate of troposphere, e.g., would be always hyper-adiabatic, whereas we well know it is, at large scale, adiabatic or at least hypo-adiabatic. No. We've been over that. The lapse rate is in radiative disequilibrium; the troposphere has to have net radiant cooling. See Real Climate thread - June 2011 Unforced Variations. Aside that, it is undeniable that the atmosphere, by means of the temperature gradients, behaves as a scavenger which sweeps and collects The temperature profile shapes the radiant flux profile. There's no 'scavenging', 'sweeping', 'collecting', except in limited analogy; - the radiation just goes where it goes; it's emitted at higher rates at higher temperatures, at lower rates at lower temperatures; optical properties determine the rate of emission per unit volume or for a given temperature; they also determine the rate of absorption per unit volume for a given incident flux. Radiation from all levels can reach space in so far as the intervening layers are transparent - but they can't be transparent if they can also emit, hence, greater fractions of what are emitted from higher layers can reach space. If you can't be bothered to distinguish reality from fantasy, I can't help you. I'm done.
80222. Neven at 06:27 AM on 6 July 2011
       Trouble Brewing in the North
       Why, don't they have any good wine where you live? :-P
80223. Chris G at 06:18 AM on 6 July 2011
       The Last Interglacial Part Two - Why was it so warm?
       TIS, I have some quibbles: a) "When the NH is in summer, the Earth is the warmest." By what measure, total heat content or atmospheric temperature? Oceans have a higher heat capacity than common rocks; it takes more Joules to heat them by mass. The same amount of energy received over the ocean would show less temperature change than it would over land. Plus, oceans tend to circulate more than rock. So, it makes a difference. b) "TSI does not dictate when the Earth is warmest or coldest, only the season of the NH." It would be news to me that a greater or lesser amount of energy coming in has no effect on the energy content (and temperature) of a body. If it is "only the season of the NH", then it is nothing else. c) I think you are arguing against TSI having an effect over many years by showing that it doesn't have much effect within a year. That doesn't make a great deal of sense.
80224. John Hartz at 06:13 AM on 6 July 2011
       Trouble Brewing in the North
       When will the Vikings be able to plant vineyards on Baffin and Ellesmere islands?
80225. JMurphy at 05:53 AM on 6 July 2011
       German Energy Priorities
       quokka wrote : "You ask what else is wrong with the shopping list of Table 1." Not quite. I asked about the rest of the article.
80226. JMurphy at 05:51 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       Mark Harrigan wrote : "I agree it is hard to find reliable life cycle emissions data that most would accept life cycle emissions is one source but many would discount it because it's the industry talking. I think it is pretty reasonable though and here is an independent source that suggests nuclear is on a par with Wind emiisions comparisons" Unfortunately, even your second link could be seen as "the industry talking", stating : Prof Lenzen has just completed a study, commissioned by the uranium industry... And that source differs from the Savacool link given on the German Energy Priorities thread, i.e. : Nuclear 66 gCO2e/kWh Wind 9-10 gCO2e/kWh Different from BBD's figures too - although, presumably, he/she will tell us why he/she is right ! ;-) And it ends with these wise words : Rather than detail the complexity and variation inherent in the greenhouse gas emissions associated with the nuclear lifecycle, most studies obscure it; especially those motivated on both sides of the nuclear debate attempting to make nuclear energy look cleaner or dirtier than it really is.
80227. Steve Brown at 05:48 AM on 6 July 2011
       The Last Interglacial Part Two - Why was it so warm?
       I'm afraid that orbital forcing cannot be used as an explanation in isolation for the warming of the Last Interglacial. Feedback effects from vegetation and albedo change as well as GHG composition of the atmosphere will make a contribution. If you read the Crucifix & Loutre paper that I link to, they find from modelling studies that albedo feedback from vegetation changes quadruple the direct effect of the orbital forcing.
80228. les at 05:37 AM on 6 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       260 - now Normal might like to google something like "lyapunov exponent double pendulum" and discover some amazing, real science, behind "unpredictable" chaotic systems.
80229. BBD at 05:32 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       Tom Curtis #150 You say:

       2) Every single claim you have made about me and my beliefs to date has been false. You will no doubt ignore this and continue constructing falsehoods because it suites your debating style. But other participants should be aware that your ability to correctly understand an interlocuter closely approximates zero.

       And also:

       That already exceeds the 0.04 figure. Perhaps the nuclear industry does not count cancer deaths from radiation exposure in their figures. No doubt they will also assure us that smoking does not cause lung cancer.

       Your discussion of an outline plan for renewables generation at (4) is essentially Jacobson & Delucchi, and I linked to a comprehensive critique when I first joined this thread. Coincidentally, new evidence is coming to light about the lacklustre results from the Colorado Integrated Solar Project which has a direct bearing on our disucssion.
80230. BBD at 05:15 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       Moderator #148 I stand surprised and corrected. I should have said Janus-headed. My apologies.
       Response:

       [DB] Your link is bad.  Not that any even oblique reference to Janus at all would be needful in a comment thread on climate change.

       This entire tangent of the dialogue is getting out of hand.  All parties, please focus on the topic of the discussion.  Thanks!

80231. Albatross at 05:10 AM on 6 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       OK, Make that tonight, need to take care of some work.
80232. Tom Curtis at 05:01 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       CBDunkerson @149, shutting down the old power stations before you know you can get permits for a new station means cutting of your revenue stream with no guarantee that it can be renewed. It is not a viable business model.
80233. Tom Curtis at 04:57 AM on 6 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Albatross @261, I'll certainly look forward to it :)
80234. Tom Curtis at 04:55 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       DB @148, lest there be any doubt, this is the definition of "two faced" as used in the definition you refer to.
80235. Tom Curtis at 04:53 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       BBD @147 1) I am still not interested in discussing anything with you. You repeatedly ignored my direct statements in previous posts to try to construe me as a straw man. I consider that sort behaviour discourteous, and a refusal of rational debate. Where I a moderator, I would invite you to post elsewhere as the only opposing views you appear willing to respond to are those you construct yourself. 2) Every single claim you have made about me and my beliefs to date has been false. You will no doubt ignore this and continue constructing falsehoods because it suites your debating style. But other participants should be aware that your ability to correctly understand an interlocuter closely approximates zero. 3) In particular your claim about what I have read and haven't read have on all occasions been false. In this particular instance I had read table 3.3, and the introductory remarks. I had followed up on two of the five (or was it six) references, but one was in german, and the other only available on a cd-rom. I intend to follow up on the others tomorrow, time permitting. As it stands, I still have no information as to whether mining and processing costs are included in the lifetime CO2 emissions for nuclear power. Indeed, I have no idea, for it is not specified how the EU Communication Commission took a range of 3 - 40 from their source documents and turned it into a value of 15. Seeing you are either unwilling or unable to cite original studies that actually specify their methodology, you are tacitly arguing from authority, and I will certainly, and happily point that out. 4) (And finally), it is certainly possible to build a power generation system consisting entirely of solar thermal and wind power generation with the following features: a) The solar thermal peak generating capacity can meet the full system needs; b) The solar thermal plants have back-up gas or biofuel heating capable of generating peak capacity; c) The wind capacity can handle 50% of peak load under normal wind conditions; d) When wind power is being generated, solar power in excess of demand is diverted to thermal storage (or pumped storage); e) When wind capacity falls, solar power is picks up the load if possible; f) If combined wind and solar capacity falls below demand, thermal (or pumped) storage picks up the load; and g) When wind, solar and stored capacity cannot handle the load, the auxiliary gas or biofuel is used to meet system load. The system has the virtue that it can always meet designed load requirements, but that it only emits CO2 when renewable sources do not meet current load requirements. It has the further advantage that the gas or biofuel auxiliary, when called upon, is only maintaining heat in a system already brought up to operating capacity by solar or stored thermal, and hence requires no "spin up" time. I make no claim that this is the best or most efficient way to deploy renewables, only that it is possible. Because it is possible, renewables can meet almost all power requirements in most countries, supplemented by either gas or better biofuel. The question is then, not is that possible. The question is is it the best way to go, ie, is nuclear cheaper, and/or does it have a lower emissions profile overall, and/or is it safer. I do not have the answer to that question, though I would like to. On the other hand, I don't need to in that if governments would leave both renewables and nuclear as open options with no subsidies including on research, or equivalent subsidies, and with a carbon price, the power companies will quickly find the cheapest combination of technologies. In the mean time I do not trust nuclear advocates who tell me renewables cannot work, and feed me obviously false data (such as the mortality rate data), and who ignore obvious questions and evade the onus of rationally supporting their views just as I distrust greenpeace advocates who do the same sorts of thing in the other direction (although probably on a larger scale).
80236. CBDunkerson at 04:46 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       BBD wrote: "This is absurd. The main reason older plant is kept running is that anti-nuclear activism makes it difficult to get new plant built." You say my position is absurd... and then seem to agree with it. Yes, nuclear power companies are continuing to use outdated power plants because they want to make money and can't get newer ones built... because a few of the outdated ones have had nuclear accidents which have turned many people against nuclear power. If you want people to trust that your technology is safe you shouldn't continue using older versions of it which are known to be unsafe long after they were supposed to be decommissioned. What part of that (seemingly obvious) analysis is to you "absurd"?
80237. Albatross at 04:26 AM on 6 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Hello Tom et al., With reference to the ongoing confusion about thunderstorms...I'll write up something this afternoon that I hope will clarify matters.
80238. BBD at 04:05 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       Moderator While I am well aware of the likely counter-productive results of arguing with you, I am baffled here. No accusation of deceit was made. Another analogy might be 'two sides of the same coin'. Perhaps there has been a misunderstanding?
       Response:

       [DB] This (the exact term you used) is what I based that on.

       "two-faced; hypocritical; deceitful"

       To use the term that you used is to invite any of those three interpretations, including deceit by implication.  Clarity is best, leaving naught for misinterpretation.
       

80239. BBD at 03:59 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       Tom Curtis #145

       Given that, claims that CO2 emissions for nuclear are a third of that for photovoltaics, and a ninth of that for concentrated solar need to be defended. And simply citing a table with no detailed methodology is not a defence.

       You will be relieved to know that the EU doesn't formulate pan-European energy policy on the basis of guesswork. Please see p13 III in the linked document, which you evidently have not read. It is a synopsis of the methodology. There, you will be referred to Table 3.3, which in turn will direct to to the relevant sources and references in the literature.
80240. BBD at 03:49 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       Mark Harrigan # 144 30% by 2050 is essentially the conclusion of the recent IPCC SRREN study. This is broadly in line with other projections. Unfortunately, the elephant remains firmly in the room. WRT TC's comment on spin-up is puzzling.In fact I can't really make clear sense of it. What happens at the end of a cloudy week of relatively high demand? Molten salt is a clever idea for thermal storage, but not a free pass to unlimited backup. This kind of plant design strategy is going to lead to capacity shortfalls. Baseload capacity shortfalls. I completely agree with you that this is an invitation to do more research. I completely disagree that it will ever make renewables suitable for large-scale baseload.

       Tom @ 139 I think makes a couple of good points. One is that the debate is made poorer by campaigners from any side (nuclear, anti-nuclear, renewable, anti-renewable, denialist etc) overstating issues to shore up their perspectives.

       TC is, in my view, being disingenuous. He is clearly anti-nuclear and continuously deploys FUD in furtherence of his stance. And he also seems to be treating you exactly as he treated me when I disagreed with him upthread. I will restate what I said above: Anti-nuclear sentiment is ( -Snip- ); its other aspect is ill-founded renewables advocacy. The policy 'missing link' is the frankly naive claim that western democracies will somehow turn to austerity and energy poverty and deindustrialise to make it all work. It's wishful thinking on a par with AGW scepticsim - and similarly dangerous. You conclude with a commendable appeal to reason:

       But let us not make the perfect the enemy of the good - or to extend the phrase - can we take what is good in any option and strive through logic and reason to make it better? (sorry - I'll stop preaching now ;-)

       This is laudable, but there are constraints. We do not have unlimited budgets, and the problem of opportunity cost must be addressed before a major policy mistake sends us down the wrong track. Not only can we not afford to do the whole thing twice, once for renewables, once for nuclear, the projected acceleration in warming does not allow the luxury of time. This is why I (and many others) argue that unless renewables can absolutely confound their critics and achieve near-physics-defying efficiency improvement within the next decade, they will at best give us 30% of the global energy mix by 2050. Coal is projected to be a big player - ca 40% or higher - and that's simply unacceptable. So what's on the table? Nuclear. I wish we could power a world of ca 9 billion in 2050 with renewables and fairy dust, but we can't. And this requires urgent but absolutely logical consideration.
       Response:

       [DB] Accusations of deceit are a Comments Policy violation (unless you have incontrovertible proof).

80241. John Bruno at 03:20 AM on 6 July 2011
       Great Barrier Reef Part 1: Current Conditions and Human Impacts
       I mean their inference matched their results. They did not try to make points about time periods not covered by their data. They didnt engage in unsupported arm-waving. Regarding the longer-term decline on the GBR, they did not come to the same conclusion as Sweatman et al. I was trying (sorry if I was not clear enough) to respond to the query by jmsully (#2): "My initial thought was that it focused on too narrow a question, but otherwise seemed OK. Of course this is being used by denialists to claim that "coral reefs are OK! Nothing to worry about!", but I'd be interested in your take" I agree jmsully. Fine paper. Reasonable interpretation. Everything OK. Yet, the paper - neither the text nor the results - support the argument that "coral reefs are OK! Nothing to worry about!" UNLESS you assume that the GBR was pristine 1995. And why on earth would anyone do such a silly thing? Sound familiar? Cherry picking a very short time period to argue no change has taken place, period? Inferring the absence of statistical evidence for change over a short time period means there indeed was no change (falsely assuming failure to reject the null is support for the null). Assuming 1995 (or 1998 as in surface temps) is the "baseline"?
80242. Tom Curtis at 03:18 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       Mark Harrigan @142, please note again my final @138:

       "Please note that these costs to health and in CO2 emissions pale in comparison to equivalent figures from coal. There is no basis from these considerations to get rid of nuclear power in favour of any fossil fuel, or to not introduce nuclear power as a substitute for fossil fuels. But the selective statistics used for comparison data make a proper comparison between nuclear and renewable options difficult, and significantly overstate the advantage of nuclear, if any."

       (emphasis added) Your response seems to me to spend most of its time arguing against a position I explicitly disavow. I have to say that for you to follow BBD's example of arguing straw men as a substitute for actually reading the post that is supposedly being responded to is not a good sign. Please do not continue doing so as I find it very uninteresting to discuss issues with people that discourteous. When it happens once, I assume it was just an error. If it happens repeatedly, I assume the person is incapable of a polite and reasoned discussion. Having said that, I agree that mineral mining is safer than coal mining, and open cut mining safer than underground mining; but was unable to get figures for open cut mineral mining (which would be directly comparable). I can say from experience in the mining industry that deaths from mining are comparable in rate to deaths from surface workings (concentrators, smelters,maintenance facilities), so while the figures are inaccurate, they will be of the right magnitude. That however, is not the point. The point is that even deaths from Chernobyl alone more than exceed the listed deaths per terraWatthour you listed. Arguably the deaths from construction equal or exceed those listed. Deaths from mining and processing are also likely to be a significant fraction of those listed, and possibly exceed them. Consequently the value listed is simply not plausible. Because the value is much smaller than the value for coal, these problems are not a problem in that comparison. However, they call into question the very dubious (IMO) claim that Nuclear power is eleven times safer than Photovoltaic Solar power, and nearly four times safer than off shore wind. With regard to emissions, I am less sure the comparisons made are inaccurate, and would not question them except for the repeated examples of glib dismissals of any concerns by nuclear advocates (not to mention the attempts to shoe horn anyone who raises concerns as a greenpeace radical). However, there is a distinct difference between wind and solar power and nuclear. They both have CO2 emissions from construction, and these emissions can in principle be eliminated (except perhaps from concrete construction). But in addition to that, nuclear has a fuel cycle, which wind and solar do not. Given that, claims that CO2 emissions for nuclear are a third of that for photovoltaics, and a ninth of that for concentrated solar need to be defended. And simply citing a table with no detailed methodology is not a defence.
80243. The Inconvenient Skeptic at 03:18 AM on 6 July 2011
       The Last Interglacial Part Two - Why was it so warm?
       I am going to disagree that the difference in insolation was not sufficient to cause the warmer Eemian Interglacial. We agree at the 14% higher summer insolation that took place 126,000 YBP. You state that TSI is not sufficient to account for the warming, but that ignores the geographical bias that currently exists for the temperature of the Earth based on where the peak energy intersects the Earth's surface. Under the current orbital parameters the peak energy takes place on January 5th. The minimum energy is taking place right around today (July 5th). The difference is about 6% in total TSI between those two points. So in about a month the Earth should be at it's coldest point of the year if TSI was the determining factor. It should be noted that today is the coldest day on the Moon because TSI is the main factor there. The Moon will be about 6K warmer on January 5th when it is closest to the Earth. So TSI only would dictate that the Earth behave in the same manner, but the Earth's temperature cycle is independent of TSI and is dependent on the season of the NH. When the NH is in summer, the Earth is the warmest. When the NH is in winter the Earth is the coldest. TSI does not dictate when the Earth is warmest or coldest, only the season of the NH. The 65N simply acts to amplify the effects of the natural temperature cycle that the Earth currently displays. That 14% higher summer insolation would have caused the summer time temperatures to be MUCH higher than the NH experiences today. Jones Annual Temperature Dr. Jones is the one that described the annual temperature swing of the Earth and it is strictly seasonally based and not TSI based. The Milankovitch cycle really just amplifies the natural cycle that exists each year by either increasing the decreasing the amplitude of the yearly cycle. The peak summer energy 126,000 years ago is more than sufficient to fully explain the much warmer temperatures at the time.
80244. Mark Harrigan at 02:57 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       BDD @ 136 Thanks for your comments I think an important point to pursue in any discussion of safety is the separation of risk from hazard. Too often they are conflated and mean the discussion gets derailed. Regardless of how much lower risk new technology is (and I agree it is) the hazard is not really mitigated. I think we are in agreement the real issue to make Nuclear an acceptable option is that management and regulation must be rigorous, transparent and accountable. In my opinion until that happens, and is proactively addressed by the Nuclear industry the politics against it as an option will simply prove insurmountable. A pity but that's the political reality. On renewables and what sparked this whole thread I may share your views about the current state of renewable but the 30% limitation you mention seems somewhat arbitrary to me? Tom @ 139 I think makes a couple of good points. One is that the debate is made poorer by campaigners from any side (nuclear, anti-nuclear, renewable, anti-renewable, denialist etc) overstating issues to shore up their perspectives. I would like to move beyond that insofar as it is humanly possible. I also think his framing of the "spin-up time" issue makes good sense. What is needed I think is a "utility" that uses a mix of wind (with intelligent predictive anemometering) and solar thermal supported by gas/biofuel turbines (or similar) to manage the variability.(gasp - they might even have some nuclear too!) The trouble is (as I see it - so just a hunch) that everyone wants to push their own barrow and there's very little evidence of anyone using a multi-pronged approach There is a plan in Australia (one I think that makes some brave/unrealistic assumptions and is way beyond our current capital investment capabilities) here beyond zero which has been thoroughly critiqued here beyond zero critique Does that mean the idea is dead in the water? No, it means it needs more work. My point is that our challenge in the debate is not simply to point out what is wrong with any proposal (though that is important) but to use our skills and creative energies to try and suggest better ways to move forward and create improvements. We need to move past everyone just pushing their particular hobby horse of a solution. Given that we can move past the denialist vs AGW is real debate (which is maybe only just starting to happen in Australia I'm sorry to say), the problem in the debate moving forward , as I see it, is that (as I said above in #142) we need to acknowledge that the world is full of lesser evil choices. Wishful thinking for renewables don't make them any more real but also just attacking renewable options doesn't make them any better. Similarly denying the nuclear option based on FUD seems unwise to me but we also need to confront the difficulties head on. I am interested in Mark Diesendorf's proposal (the article that sparked this whole thread) because it is a serious attempt to do that - I agree it may not be perfect (probably far from it). But let us not make the perfect the enemy of the good - or to extend the phrase - can we take what is good in any option and strive through logic and reason to make it better? (sorry - I'll stop preaching now ;->)
80245. KR at 02:40 AM on 6 July 2011
       It's the sun
       JoeRG I believe the correct Stott reference is to Stott et al 2006, Transient Climate Simulations with the HadGEM1 Climate Model: Causes of Past Warming and Future Climate Change. A very similar work, although more focused on predicting than back-casting, that isn't pay-walled is Stott et al 2006, Observational constraints on past attributable warming and predictions of future global warming. Figure 1 of the second link shows a similar pattern, with current warming not explainable without anthropogenic influence. "...you argued -using this figure- that the models are 'excellent'. I showed -using the same figure as well- that they are not, at least if modified by the IPCC, because of mismatches to reality and, as shown by pointing out the difference to Stott, wrong adaptations." The models, with anthropogenic forcings included, track observed temperatures quite well. They seem to include a fairly accurate internal representation of the physics and the effects - I don't think you have any basis for stating otherwise. As to ocean warming (a completely different topic, mind you, and you should look at the appropriate links using the Search box), keep in mind that (a) our measurements of OHC are far from complete, especially at depth, and (b) circulation variances in the oceans are expected to show variations on a 5-10 year timespan.
80246. BBD at 02:27 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       CBDunkerson #140

       If they instead continue to operate poorly designed reactors decades past their originally intended 'end of life' more nuclear accidents, and thus continued public opposition, are guaranteed.

       This is absurd. The main reason older plant is kept running is that anti-nuclear activism makes it difficult to get new plant built.
80247. Mark Harrigan at 02:19 AM on 6 July 2011
       A Detailed Look at Renewable Baseload Energy
       @Tom 138 I'm sorry Tom but it is totally fallacious to extrapolate from an average figure of deaths for all mining to a figure for uranium mining. All mining profiles are different but perhaps the most important is that the majority of Uranium mining is either open cut (stripping off overburden and refining) or in-situ leaching as opposed to Under Ground (such as in long wall coal mining). Underground mining is inherently more dangerous. So I dispute your figures - they are not logical I agree it's hard to get precise figures but even if you allow a significant increase in the figure I quoted - and say it is wrong by a factor of 100 - it is still two orders of magnitude better than coal. And this doesn't take into account the 100,000's of early deaths the UN attributes each year to the use of extractive fossil fuels. So I do not think you can pretend that Nuclear is a real problem on the basis of its comparative mine safety. As to my statement "The technology is CO2 free in operation" - well - it IS. I meant exactly what I said - the issues you raise of CO2 emissions relate to extraction (which I made clear) so I feel you either misunderstood or are being disingenuous. The Green movement often slanders uranium as somehow producing more CO2 than alternatives over the lifetime of the plant by pumping up figures involved in mining and processing. Really this is a furphy. Of course there are emissions associated with mining and extraction - just as there are associated with the extraction of metals and refining, forging and fabrication of Wind Turbines and Silicon for Solar Panels (which is actually quite energy intensive!). That all depends on what methods you use to power those processes and should really be the subject of a separate comparison. What matters is that once the Nuclear Plant is in place it is essential CO2 emissions free. I agree it is hard to find reliable life cycle emissions data that most would accept life cycle emissions is one source but many would discount it because it's the industry talking. I think it is pretty reasonable though and here is an independent source that suggests nuclear is on a par with Wind emiisions comparisons Regardless I think it is hard to conceive of any logic that would make Nuclear a "bad" CO2 option - I think it's a furphy raised by those who are ideologically opposed to nuclear power - It's the same sort of misrepresentation that denialists use only from a different direction. I prefer to be data and logic driven and not come from an ideological view point of support or oppositiion The real issue with Nuclear as an option is, I believe, as I have stated. On the plus side it's reliable and will contribute to enormous CO2 emissions reduction - It's proven technology and generally able to be implemented in most geographies (excluding those that are seismically at risk) - which put' it ahead of hydro and geothermal which have severe geographical limitations. With modern technology designs the risk are frankly extremely low BUT - the hazard is enormous -and if something does go wrong humans have not demonstrated an ability to manage it. This compounded with the human fallibility issue I mentioned earlier is a very big negative. The only way I can see forward for nuclear is if it is highly regulated AND the industry steps up to the plate and imposes on itself a rigorous accountability, management discipline and transparency to better manage itself. I'm not sanguine about that happening but I see it as the only way forward for Nuclear if we want to reduce CO2 emissions by as much as the science says we need - because (as I will post elsewhere) renewables are simply not (YET) up to the task - or at least it is not proven that they are - again part of the debate that is needed The cold truth is that the world is full of lesser evil choices. We need the debate to mature to that fact and have a sensible informed discussion about the nuclear option and renewable options- not one based on fear or poor logic or data or wishful thinking.
80248. BBD at 02:17 AM on 6 July 2011
       German Energy Priorities
       dana1981 #31 It's also vital to consider what is coming. Electrification of personal transport (with overnight charging the norm) and increased use of day/night AC in cities will drive baseload demand upwards significantly. High-renewables scenarios invariably require much reduced demand in order to 'work'. It's another reason to be extremely sceptical of such claims.
80249. Tom Curtis at 02:16 AM on 6 July 2011
       German Energy Priorities
       quokka @33, what is the discount rate? Also, I consider the idea of discounting future costs for calculation of levelized costs dubious. Assuming we are looking at a long term energy solution, then eventually power plants will exist in all phases of their cycle in about even numbers. Therefore the ongoing cost of the industry will include all features including decommissioning at current values, and that is the cost we are interested in. In this our perspective is different from that of an investor (for whom discounting is appropriate).
80250. JoeRG at 02:15 AM on 6 July 2011
       It's the sun
       ... in (a) as obtained from 58 simulations produced by 14 models with both anthropogenic and natural forcings. ... The simulated global mean temperature anomalies in (b) are from 19 simulations produced by five models with natural forcings only. Well, this is taken from the caption of the figure (and I do not expect that all of the models were made by the autors). So what would you expect from one who's reading this, unable to find any description (because of dead links, just a hint that leads to Stott) and finally realizing that the graphs did match neither the original model nor the physical behaviours that are to expect? Should he say "hurray, it's from the IPCC, it's fine"? Of course, very amazing. I suggest you check the various reports for links to the original works. I would, if you can give me the list of the used models. I can't get it from the IPCC page. Regrettably there is no 'Appendix 9C' -for whatever reasons- where the underlying papers/reports would have been listed. Besides, you argued -using this figure- that the models are 'excellent'. I showed -using the same figure as well- that they are not, at least if modified by the IPCC, because of mismatches to reality and, as shown by pointing out the difference to Stott, wrong adaptations. (Of course, it's a completely different topic.) Back to topic. You are right, the flares are quite a hypothesis. But, perhaps you can give another possible explanation (eventually a paper) for the needed ~3W/m² of positive radiative imbalance. With the value of Trenberth 2006/2009 (0.8..0.9W/m²) it would need about 5 years to get the observed OHC-rise (by 6*10^22J) that obviously occured within a single year - given that the measurements are correct.

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