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Comments 89351 to 89400:

  1. Dikran Marsupial at 08:02 AM on 11 April 2011
    Has sea level rise accelerated since 1880?
    daniel maris@72 smog is an urban phenomenon, I can't see how its removal can account for the warming of the U.K., which is also evident in rural locations. As for sea level rises, the Netherlands are wealthy and can afford to take measures to guard against sea level rises, Bangladesh is another matter entirely. The comment about dinosaur methane was about 10 days late, but it did make me laugh! ;o)
  2. Has sea level rise accelerated since 1880?
    Muoncounter - Referring to past times, I was meaning that climate modelling is pretty dodgy if you have no way of estimating say methane generation from dinosaurs (that's just one example). Climate modelling can only be valid I think on the basis of current data. My position on sea level rise is clear: that if it is in the order of less than say 5 mms per annum, then humanity can adapt to it without too much trouble. There may be some casualities of such a rate of change (just as there will be casualties from not letting sea level rise, given that land everywhere is either going up or down relative to the sea), but not many.
    Moderator Response: See, and comment on, the post "It's Not Bad." Enter that in the Search field at the top left of this page, or find it by browsing the Arguments you can see by clicking the "Arguments" link in the blue horizontal bar at the top of this page. Further off topic comments will be deleted, even if parts of them are on topic. You've already been politely warned, so now you're just getting on my nerves. [Dikran Marsupial] You also ought to read Are surface temperature records reliable?.
  3. How I lived through a carbon tax and survived to tell the tale
    @Gilles "the high price of FF will lead to a reduction of their use anyway, with or without tax - and much likely much more than with a tax." Eventually yes. We certainly agree on that, but the fact that eventually the price will be high enough to discourage FF use is mostly meaningless. At least in the context of climate. What matters is will that happen fast enough to avoid the significant costs associated with climate change? The answer is almost certainly no, because the price is artificially low (see my previous comment).
  4. Has sea level rise accelerated since 1880?
    Logicman, I think we have to move away from big hydro schemes. However, are you saying that agricultural production is LOWER now in Egypt following the Aswan Dam opening compared with before? I very much doubt that is the case, and that really is what I am saying - humanity is v. adaptable and will adapt if the rate of change is slow enough. You're making a prediction about what will happen over the next 90 years, which is fair enough, and we or our heirs will see whether and to what extent it comes true. As it is (I live in a tidal area) I have seen no evidence of the effects of sea level rise at all and have not read of any specific effects in the media (although you get erroneous connections made with such phenomena as coastal erosion which is always with us).
  5. Has sea level rise accelerated since 1880?
    Albatross, AS for Tamino's analysis, well it could be correct, but of course Tamino is arguing against a paper by "Houston and Dean" published in the Journal of Coastal Research I think. Presumably Houston and Dean are reputable scientists and would in turn come up with lots of counter-objections to Tamino's analysis. I know enough about statistics and surveys to know that by asking the right sort of questions in the right series and by tweaking confidence levels you can come up with the answers you want. I think there are just so many variables involved in this debate that it is impossible to say at the moment whether major AGW is taking place. I tend to focus on personal experience. There's no doubt that the British climate is a lot warmer than 50 years ago. But that might be explained by the removal of smog through air quality legislation. I am also aware through personal experiecne that London is much, much warmer than surrounding parts and also that weather stations taht were once in the countryside or in fairly isolated airports are now in built up areas. My main issue though with the sea level rise discussion was the assumption that it would have a catastrophic impact. I don't see that the rises most scientists are talking about would have such an impact. I think it is perfectly reasonable for me to point to the Netherlands - a fact in itself - as a country that suffers no discernible negative effects from being located in large part below sea level. What can be done in the Netherlands can be done elsewhere, if the worse comes to the worse. Of course a 9 metre rise over a short period would be a different matter. But most scientists don't seem to think the ice sheets will melt. So if we are sticking with majority scientific opinion, that has to be set to one side.
  6. How I lived through a carbon tax and survived to tell the tale
    "But it sounds like you are arguing that higher prices wont lead to a reduction of FF use. Is that correct?" Well, obviously I have some difficulties to be understood - because I'm arguing exactly the opposite - the high price of FF will lead to a reduction of their use anyway, with or without tax - and much likely much more than with a tax. The contradiction is by those who claim that a tax would be efficient to reduce it, but not the rise of extraction cost - because for the customer, the effects are the same and it is illogical to think that the demand would decrease in one case and not in the other one. So actually the tax is useful to avoid using FF... that wouldn't have been used anyway because they're much more expensive that the tax could produce.
  7. Has sea level rise accelerated since 1880?
    Muoncounter, You are making an assumption there. I have already made clear I support a rapid move to renewable energy production supported by carbon capture gas. So if CO2 is the cause of global warming then I am on your side of the argument. For me renewable energy is attractive for a wide variety of reasons but the precautionary approach to carbon addition is one. However, I am simply not impressed by a lot of the climatist arguments and the idea that a slow sea level rise will be a catastrophic I find unconvincing. I mean, we've already had a slow sea level rise according to you with absolutely no discernible effects. (Not to say there haven't been effects, just that they have not impinged on our national life.)
  8. How I lived through a carbon tax and survived to tell the tale
    Howard Seaward wrote : "Name just one example where socialism or communism solved anything. If FF are truly the issue that many think they are (and many don't), and there becomes a great demand for the solution, then some ingenuitive capitalist(s) will find a way to solve the problem." Coincidentally, I am currently watching a programme on UK TV about the Soviet space program and next week is the 50th anniversary of the first man in space - accomplished by the same country that put the first satellite in space. Can you remember what form of government they had then ? And I believe China is now leading the world in investment in renewables and is fast increasing the share of its energy coming from renewables. That should solve some problems. What system of government do they have in China and how do their figures compare with the Capitalist West ?
  9. How I lived through a carbon tax and survived to tell the tale
    @ Gilles " in other words, if a carbon tax is efficient to reduce the consumption, why wouldn't the consumption decrease with the mere influence of growing extraction costs - even without a tax" There are many reasons. First there is already a global infrastructure set up for FF use, which brings with it a whole lot of inertia that resists change. Add to that the massive political pressure that FF companies exert on politicians. And finally the cost of FFs are artificially low (even though they are rising), and still cheaper than the alternatives (which not only need to be cheaper but need to overcome the FF inertia). Why artificially low? Because the true cost of FF is externalized. No one (except in a few ares which have implemented carbon pricing) pays to dump GHG emissions in the atmosphere, despite the well established science that indicates that this will have severe costs in the not to distant future (actually there are costs even now). Add to that the cost of particulate emissions (mainly from coal) and you have massive externalities which are not reflected in the price of FF. That is the crux of the problem. But it sounds like you are arguing that higher prices wont lead to a reduction of FF use. Is that correct?
  10. How I lived through a carbon tax and survived to tell the tale
    Re: Canada fossil fuels. If it helps anyone, here are some resources: map of oil and gas producing areas: http://atlas.nrcan.gc.ca/site/english/maps/economic/energy/oilgas energy sector statistics: http://www.nrcan.gc.ca/eneene/statstat/index-eng.php energy use database 1990 to 2008. http://www.oee.nrcan.gc.ca/corporate/statistics/neud/dpa/comprehensive_tables/index.cfm?attr=0 I have noticed that many Canadian science-related sites are slow to update. I get the impression that this is a funding problem.
  11. A Plan for 100% Renewable Energy by 2050
    If anyone is interested in a little easy listening, here's an interview with Shai Agassi of Better Place electric car battery swapping station fame; and a CNN article for food for thought.
  12. The e-mail 'scandal' travesty in misquoting Trenberth on
    @19 Gilles: "Moderator : the only figure of this post has the following legend : "Figure 1. The global annual mean Earth’s energy budget for the March 2000–May 2004 period in W/m2. The broad arrows indicate the schematic flow of energy in proportion to their importance. From Trenberth et al.b"" Gilles; thank you for pointing out a typo in my footnote. It's been fixed.
  13. How I lived through a carbon tax and survived to tell the tale
    Gilles: "Marcus, but after all, if you're posting here, is it not to convince unconvinced people? because you would agree that it is a waste of time to convince already convinced people !" You are wasting time. You also contradict your own argument/views in your statement.
  14. How I lived through a carbon tax and survived to tell the tale
    "it is evident that the increase in gasoline prices has caused many consumers to buy more fuel efficient vehicles." That belongs to the "A" category only....
  15. actually thoughtful at 03:36 AM on 11 April 2011
    How I lived through a carbon tax and survived to tell the tale
    Based on new car sales data for British Columbia since 2001, it is evident that the increase in gasoline prices has caused many consumers to buy more fuel efficient vehicles. The market share of subcompact and compact passenger car sales has increased steadily while the market share of larger cars, SUVs, pickups and minivans has declined. http://www.fin.gov.bc.ca/tbs/tp/climate/A6.htm {not much in the way of information...} This is where it should be: http://www40.statcan.ca/l01/cst01/manuf32k-eng.htm (energy information is censored) GREAT site! (especially in regards to my earlier point about the best way to change human behavior) http://scorecard.sightline.org/energy.html The best I found was this: http://www40.statcan.ca/l01/cst01/trade37c-eng.htm The upshot is gasoline up, diesel down (2009 compared to 2008) Canada apparently censors data on fuel and coal usage (and many other things).
  16. A Plan for 100% Renewable Energy by 2050
    Gilles - 1. I don't deny that we may be approaching the peak for oil, but oil is not the only hydrocarbon and the peak may still be decades away. Gas supplies look like they are nowhere near peak. 2. My problem is with people who read graphs as though they are causal factors themselves. All the supply and demand graph does is tell you how people are likely to react to the cost changes brought about by technology. In terms of future energy supply, supply and demand are not in my view that important. The key factors are what technologies can be delivered at what cost. Of course governments manipulate energy costs through taxes and subsidies. About 70% of the price of petrol (gasoline) in the UK is actually made up of government taxes. And people do reduce their mileage if petrol costs rise significantly. 3. You know of no government that is based its energy plan on energy storage of renewables? I agree that is the case, but things are moving fast. I think this will be the next stage - developing affordable storage. As for Iceland, I think that reflects the issue of political will. I presume a lot of their oil imports are going into petrol/diesel for road vehicles. There's no reason why they couldn't switch to electric road vehicles. Certainly both Israel and Denmark are investing in the battery changing technology which I think will revolutionise road transport as the problem of range is now solved. I know we can't do everything at once, but I think while we transform our energy base, we can use gas and coal with carbon capture as a stopgap.
  17. actually thoughtful at 02:51 AM on 11 April 2011
    How I lived through a carbon tax and survived to tell the tale
    Regarding hard data on BC greenhouse gas emissions, apparently there is a two year lag on emissions reporting (although one would think fuel purchases would be more readily available). So measured emissions results won't be available until sometime in 2012. While I am in favor of these regimes - their first effect will be a run-up in burning things - like wood and grass and.... It isn't clear that this will be a net positive (as bio burners exist that are inefficient).
  18. Christy Crock #2: Jumping to Conclusions?
    use the new firefox 4
  19. A Flanner in the Works for Snow and Ice
    Ken Lambert @55, I apologize to everyone. I have made an inadvertent error which sabotages my effort to give Ken Lambert everything he could possibly ask for his theory. To correct the error, I have proceeded as follows: 1) For each of May 21st 2011 and July 20th 2011, I have used the azimuth and altitude calculator referred to by KL to calculate the sun's altitude at 00:00, 01:30, 04:30, 07:30, 10:30, 13:30, 16:30, 19:30 and 22:30. 2) From one, I took the lowest altitude for each of the time intervals bracketed by those numbers, and including the interval from 22:30 to 01:30 as being one interval. I then rounded down to the nearest whole multiple of five degrees. This gives me altitudes for each of the time intervals of 5 (5.1) degrees for the three hours surrounding midnight; 5 (6.2) degrees for the three hours around 3 am and 9 pm; 10 (13.8) degrees for the three hours around 6 am and pm, 25 (25) degrees for the three hours around 9 am and 3 pm, and 30 (33.8) degrees the three hours around midday. (Numbers in brackets are the minimum values before rounding.) 3) I then compared these angles to the second table in 54 above to determine the reflectivity for each angle. Based on the curve for circular light (as light from the sun is not polarized), the albedo for a 5 degree angle of incidence is determined as being 0.6; for a 10 degree angle of incidence, 0.3, and for 25 and 30 degree angles of incidence, 0.05. 4) I then take the average of the values, which comes in at 0.31875 I shall round this up to 0.35, which compares to the 0.2 value I mistakenly calculated above. Because the two dates chosen are each 30 days seperate from the summer solstice, I believe this provides a reasonably conservative estimate of the average albedo over the summer period at 75 degrees latitude. If Ken Lambert thinks this is insufficiently biased in his favour conservative, he can let me know and I will do the calculation for 45 days before and after the solstice. Making this adjustment reduces the additional energy absorbed over the summer according to the conservative estimate from 2.2*10^21 to 1.7*10^21 That is still nearly double the 9.25*10^20 which we can expect from the additional forcing as calculated by Flanner over that period. It is still sufficient energy to melt 1.9 million square kilometers of 3 meter thick ice, or 25% of the remaining icecap. And it is still approximately 3 times the energy annual energy influx that Ken Lambert insists, "Therefore the Arctic must absorb less (much less) than the uniformly distributed portion of 6.4E20 Joules/yr." And it is still 17 times greater than the energy which Ken Lambert misrepresents Trenberth as indicating is the maximum absorbed in the arctic. Ken Lambert questions some of my other figures without being explicit. All are adequately explained - but if he feels my using a 90 day summer, or ignoring the effects of waves, or whatever, is insufficiently biased in his favour conservative, he again need only let me know. Ken Lambert would also do well to learn the meaning of "Gish gallop" before he makes a complete fool of himself.
  20. Christy Crock #2: Jumping to Conclusions?
    Alexandre #1 - we'll address your question in Christy Crock #3. Stay tuned.
  21. How I lived through a carbon tax and survived to tell the tale
    [snip] Michael "-on the one hand you tell us that global fossil fuel consumption will continue to increase," Sorry but which post of mine are you referring to ? I don't remember having addressed this point. I said the oil consumption is to level off. For the other FF, there is still a margin for progression , but limiting the CO2 around 550 ppm at most - see Hansen et al. 2008 if you need a reference.
    Moderator Response: [Dikran Marsupial] attempted moderator trolling snipped.
  22. A Flanner in the Works for Snow and Ice
    Tom Curtis #54 Stick to facts rather than emotive terms such as 'bad' Tom. Before we start on your 'Gish Gallop' as this site is wont to say, please explain what you mean by 'zenith' angle? The angle which the sun's rays strike the surface of the Earth is usually called the 'angle of incidence', or 'altitude'. At 75 degrees N latitude, at the summer solstice (Noon, June 21) this angle would be 23.4+(90-75) = 38.4 degrees. At midnight it would be 23.4-(90-75) = 8.4 degrees. Yet you say: "Over the summer months, at 75 degrees North, the average Zenith angle is about 57 degrees, with the sun varying from 57 degrees to 3 degrees above the horizon during the 24 hour day. I will treat the sun as having an angle above the horizon of 55 degrees for 3 hours (around noon), 45 degrees for 6 hours (around 9 am and 3 pm), 30 degrees for 6 hours (around 6 am and 6 pm, 15 degrees for six hours (around 3 am and 9 pm), and 0 degrees for 3 hours (around 'midnight')." How did you get these numbers Tom?? Here is a calculator you can use to check my numbers if you like: http://jamesrbass.com/sunform.aspx
  23. How I lived through a carbon tax and survived to tell the tale
    well sorry for abusing of your patience, Marcus, but after all, if you're posting here, is it not to convince unconvinced people? because you would agree that it is a waste of time to convince already convinced people ! there're much more interesting things to do in the world ! now I come to the most weird aspect of the carbon tax , that I didn't address up to now. (Yes , there is worse ! ) if your "above facts" are true , why wouldn't the natural increase of extracting costs do exactly the same effect ? in other words, if a carbon tax is efficient to reduce the consumption, why wouldn't the consumption decrease with the mere influence of growing extraction costs - even without a tax - and why do all SRES scenarios predict a growing FF consumption, even after all cheap conventional resources would have been exhausted for a long time ?
  24. Arctic Ice March 2011
    so, any news from Nares ice bridge and Kane basin ? I presume that if it has not yet broken, the second prediction "Ice from Lincoln Sea will be advecting through Nares Strait by April 14th." is also less likely to happen ? that's unfortunate, because we would already be at a random chance of success (2 /4 ). Hope for logicman it won't be worse ...
    Moderator Response: [Dikran Marsupial] Google provedes this
  25. Christy Crock #2: Jumping to Conclusions?
    Daniel Bailey: I'm using Firefox 3.6.16. I don't think it's the browser... Maybe the Brazilian IP? Grypo: Thanks.
  26. Call for beta testers of the latest SkS Firefox Add-on
    Hey, is it just me or the media is dropping the "balanced" attitude? I wonder what a Boykoff&Boykoff paper would find today if they did their study again.
  27. Christy Crock #2: Jumping to Conclusions?
    I was looking at my previous post and I realized that I might not have been entirely clear. I was referring to Dr. Christy, not Dr. Emanuel in the last sentence of my post.
  28. Christy Crock #2: Jumping to Conclusions?
    i see the images fine, no idea why you are seeing the frozen terror frog, maybe a bug with imageshack?
  29. Christy Crock #2: Jumping to Conclusions?
    The pictures are imageshack. I can only see the frozen frog unless I log in there. Why so few note this? Am I doing something wrong? (moderators, feel free to delete this post if you see fit)
    Moderator Response: [DB] Which browser are you using? They display fine with Firefox. [grypo] Thanks. I fixed this. I uploaded the pics to SkS server, which is what I'm supposed to do anyway. It should not be a problem in any browser, now.
  30. How I lived through a carbon tax and survived to tell the tale
    So, to get away from Gilles pointless distraction, the main point of this article is (a) a carbon tax can make the unit cost of fossil fuel energy more expensive-leading to people using it more efficiently. (b) if the per-capita use of fossil fuels decreases, & the cost of extracting them increases, then the incentive for extracting fossil fuels will decline (c) A carbon tax will also make renewable energy options more attractive which, coupled with improved energy efficiency, will reduce fossil fuel consumption even further still. (d) Obviously this will lead, ultimately, to the fossil fuels being increasingly left in the ground. All of Gilles Hand-waving & wishful thinking doesn't change the above facts.
  31. Christy Crock #2: Jumping to Conclusions?
    That comment by Dr. Emanuel certainly belongs in a list of memorable quotes. Isn't part of the goal of a theory to be able to predict future phenomena? I'd imagine it'd be more difficult with an inter-disciplinary study such as climate science, but from what I've been hearing/reading they've been constantly improving. You'd think a credible scientist would want help improve predictive accuracy by identifying and eliminating sources of error.
  32. Christy Crock #2: Jumping to Conclusions?
    I'd like to know what explanation for the recent warming Christy endorses, and how much evidence supports it. Considering all the evidence behind AGW is not enough for him, I wonder how much evidence his theory has...
  33. How I lived through a carbon tax and survived to tell the tale
    "This is a typical post of Gilles which should be deleted because it wastes everyone elses time to read it." I tend to agree. Gilles is a massive time waster, & I think we've *all* been far more patient than he deserves.
  34. How I lived through a carbon tax and survived to tell the tale
    "Michael sweet : for which facts are you asking for references ? I posted a number of graphics- unfortunately some of them disappeared quickly, but complain to the moderation." Gilles, posting graphics without a link-& in a tiny font to boot-is pretty dodgy, especially as we've already exposed your tendency to doctor graphics to suit your agenda. You see, it keeps coming back to this-on the one hand you tell us that global fossil fuel consumption will continue to increase, yet on the other you claim that there are insufficient fossil fuels to meet an increase in consumption-so *which is it*?!?! You seem to want to have it both ways. The fact is that there *is* enough fossil fuels in the world to create a massive increase in CO2 emissions-in the near term-& that the warming it causes will cause a release of CO2 from natural sources-which I'm pretty sure the SRES scenarios account for too. Seriously, Gilles, when are you going to contribute ( -Snip- ) to any of these blogs?
    Moderator Response: [DB] Do not let him make you angry; that is a mission objective.
  35. michael sweet at 22:05 PM on 10 April 2011
    How I lived through a carbon tax and survived to tell the tale
    This is a typical post of Gilles which should be deleted because it wastes everyone elses time to read it. If Gilles is unable to determine what BAU is he needs to do his homework. He is splitting hairs to make up arguments.
  36. How I lived through a carbon tax and survived to tell the tale
    "do you know an OECD country for which the CO2 consumption per capita could be generalized to all people in the XXIth century, yes or no?" This question *makes no sense at all*. Seriously, if you can't ask *real*, *sensible* questions, then I really don't know why you even bother posting at this site.
  37. How I lived through a carbon tax and survived to tell the tale
    So Marcus you contend that the set of SRES scenario is far from covering the whole set of possibilities ? Now it is unclear for me what you're really calling "BAU", since they already encompass a very large set of various trajectories. Could you please tell me what you mean exactly by "BAU" ? how do you recognize a "BAU" from a "non-BAU" scenario ? do you have a practical rule that I could apply without asking you, another time (when you may not be available to tell me if it is BAU or not ? ) Michael sweet : for which facts are you asking for references ? ( -Snip- ).
    Moderator Response: [DB] Moderation complaints removed.

    [mc] Another thread driven radically off-topic as predicted. Further comments that do not include some 'carbon tax' content will be deleted.

  38. How I lived through a carbon tax and survived to tell the tale
    I see the "FF running out soon" issue again. Oil should run out soon (decades). There is about 6+ times more carbon in the form of coal, though.
  39. How I lived through a carbon tax and survived to tell the tale
    "Marcus , you said it was impossible to sustain the current consumption. The CO2 emissions level off but at a much higher level than the current one. How is it possible if even the current one is unsustainable ?" What I meant was that it couldn't be sustained over the *long term*-seriously, your comprehension skills are utterly appalling. We can "sustain" a significant, global increase in fossil fuel consumption over the next 50 or so years (especially oil), but an increase in consumption *will* cause the fossil fuels to run out quicker than would otherwise be the case. The point is that we cannot *afford* to increase our consumption of fossil fuels-yet we are. Nations like the US can-& should-do more to reduce their consumption of fossil fuels-through energy efficiency & renewable energy measures. We should also be doing our level best to help the developing nations to do the same. This is a point which you *still* seem utterly unable to grasp.
  40. michael sweet at 21:56 PM on 10 April 2011
    How I lived through a carbon tax and survived to tell the tale
    I am astonished that Gilles at 80 is asking for a reference when he never supplies references. A search of the current threads of this website would find this peer reviewed article of generating all energy in the entire world (including developing countries) with renewables. Of course Gilles has limited his request to only official documents which have not been written yet. Gilles blather and the responses to him have dominated this site for the past month. Gilles never cites references to his claimed "facts". The comments policy should be altered to require citation of data by frequent posters so that if he continues to troll without any references he can be limited to one or two posts a day, or banned from the site if his posts continue to be unsupported. His posts are simply his uninformed, unsupported opinion and this site is supposed to evaluate the science and relevant measured data. He will never change his mind, he does not care what the data says.
  41. How I lived through a carbon tax and survived to tell the tale
    Marcus , you said it was impossible to sustain the current consumption. The CO2 emissions level off but at a much higher level than the current one. How is it possible if even the current one is unsustainable ?
  42. How I lived through a carbon tax and survived to tell the tale
    "Yet when in 1970ish carbon emissions were below current land based natural sink absorption (3 billion tonnes carbon) yet atmospheric CO2 was still rising and it shouldn't have been according to your premise" You're right , ranyl, I forgot to answer this one.... it is totally incorrect to think that if we lower the CO2 production, the natural sinks will keep absorbing the half of the current production : they will absorb the half of the actual production - in a linearized model. That's because in a linearized approach as the Bern model, you should convolve the input emission by a "impulsive response" that behaves linearly with the emissions. If we lower the emissions, CO2 will first start to decrease, and then stabilize at a level when about one half of the real emission is absorbed (with an infinite absorption time, the amount of CO2 that will never be absorbed is about 20 % in the Bern model). This is irrespective of the rate at which we emit the CO2 - the final value will only depend on the total amount burnt.
    Moderator Response: [Dikran Marsupial] That is not correct, to a first approximation environmental uptake is proportional to the difference between current atmospheric CO2 and its equilibrium concentration. The airborne fraction is only constant because our emissions are increasing approximately exponentially. The factor of about a half is only true while our emissions increase exponentially, it has no other significance. Stabilisation depends only on rates - to reach a new equilibrium our rate of emissions cannot exceed environmental uptake - that ought to be obvious. This is true regardless of how much has been emitted. Total emissions do dictate the maximum rate of emissions that allows stabilisation. The final level of CO2 in the atmosphere is pretty much irrelevant, if we take care to minimise the disruption over the next 100 years, the residual disruption hundreds of thousands of year hence will take care of itself. BTW the Bern model is non-linear, if it was linear they could evaluate it by simply performing the convolution rather than by a computationally expensive simulation.
  43. How I lived through a carbon tax and survived to tell the tale
    "as you can see, the overwhelming majority of scenarios don't predict any "run out" with levels of consumption much higher than the current one. So can you explain me the discrepancy ? are you holding that the set of SRES scenarios is strongly biased towards unrealistic high consumption levels ?" Clearly you can't read a graph. The majority of those scenarios show a leveling off of CO2 emissions before the end of the century. Given that the bulk of the rise in CO2 emissions are expected to occur *before* 2050, I don't think they're based on "unrealistically" high consumption levels. Also, don't forget that deforestation is adding to CO2 emissions too-& that there is the CO2 currently stored in the oceans which warming will cause to be released. So the SRES scenarios are *not* based purely on fossil fuel consumption-which wants again highlights how your previous statements are based on a complete ignorance of what the SRES scenarios *actually* represent.
  44. How I lived through a carbon tax and survived to tell the tale
    "The total amount of FF consumed integrated over time is not the correct metric to look at. The natural environment has been taking up about half our emissions every year; if the rate of our emission remain below the level that the natural environment can absorb (loosely speaking), then atmospheric CO2 will not rise at an unmanagable rate. Thus if alternatives cut the rate of our emissions sufficienlty, the consumption of FF consumed integrated over time is essentially irrelevant. Burning all the FF is fine, provided we don't do it faster than the environment (possibly with our help) can cope with. " Yet when in 1970ish carbon emissions were below current land based natural sink absorption (3 billion tonnes carbon) yet atmospheric CO2 was still rising and it shouldn't have been according to your premise. Also it is generally accepted that the world is going warm up another 0.6C at least whatever happens. Everytime in the past when the world has warmed the amount of CO2 in the atmopshere (with all the natural sinks intact and larger (there were more forests bach then)!) has risen, so why now should the sinks act in a way to draw down CO2 when the world is warming and absorb any extra CO2 emitted by man? Also when the oceans warm they can hold less CO2, the ice melting over the Arctic is most liklely to create an additional CO2 source, plant pests are increasing which decreases land sinks and causes releases of CO2, as the temperature rise and autumn extends respiration increases releasign more CO2, the boreal forest in Canada has been a CO2 source since 2000, the 2010 Amazon drought just released a huge amount of carbon, the oceanic sink of Japan, Northern Atlantic and Southern ocean have all decreased their rate of CO2 removal and the Southern westerlies are heading south which again should turn the southern ocean from a sink to a source as the warming contiues. C4 plants (most grasses) don't respond to CO2 fertilization and large amounts of land have been converted to grassland rather than forest, the permafrost is melting, peat bogs are emitting more and more CO2, and as the climate changes it is predicted that many climatic systems will shift again stressing the natural sinks, add in all the other destruction of the natural sinks (deforoestation, pesticides, massive over fishing etc) and suggesting that natural sinks mean we can continue to burn fossil fuels just at the correct rate is at best dangerous. Also considering the Pliocene 350ppm is where we need to get and asap to avoid 2C in 100years, so don't we need every single drop of natural sink CO2 absorption to get anywhere near that and cease all FF emissions asap as well. And lastly all renewables and nuclear are not carbon neutral and are not environmentally neutral either, I would suggest looking up tri-nitro flouride and the fate of migratory bats in the US just reported in science express and impacts this will have farmland pests. And also look up the CO2 costs of biofuels as it is most commonly found they have a larger CO2 legacy than oil! Now don't get me wrong I in no way advocate using FF either, the crux of the matter is we need to use a lot less power and stop consuming none necessaries. So basically impossible, so maybe we should start planning for the consequences of >2C and that does mean....not worth even saying is it.
  45. How I lived through a carbon tax and survived to tell the tale
    Marcus : "For the record, yet again, I don't think we can sustain our current levels of fossil fuel consumption world wide, simply because it probably *will* run out before the end of this century. " Right. On this point I fully agree with you. Now I remind you the set of SRES scenarios http://www.bbc.co.uk/sn/hottopics/climatechange/climate_challenge/images/illustration1.gif as you can see, the overwhelming majority of scenarios don't predict any "run out" with levels of consumption much higher than the current one. So can you explain me the discrepancy ? are you holding that the set of SRES scenarios is strongly biased towards unrealistic high consumption levels ?
    Moderator Response: [DB] Enlarged image and added source link.
  46. The e-mail 'scandal' travesty in misquoting Trenberth on
    Moderator : the only figure of this post has the following legend : "Figure 1. The global annual mean Earth’s energy budget for the March 2000–May 2004 period in W/m2. The broad arrows indicate the schematic flow of energy in proportion to their importance. From Trenberth et al.b" How can you consider that discussing the accuracy of global energy budget is off topics ? why do you erase my comments about it, and my opinion about the real meaning of Trenberth's quote ?
    Moderator Response: [Dikran Marsupial] It is off-topic for this thread, but not for the thread I directed you to twice before. This thread is not about the accuracy of the energy budget, but the misinterpretation of Trenberth's private email comment.
  47. How I lived through a carbon tax and survived to tell the tale
    Gilles: "How many people in the world should have a car, ideally , following you, and for how long ?" You don't get the point at all. You don't need a car to live an advanced life style. If you believe that then you have been sold a false promise.
  48. How I lived through a carbon tax and survived to tell the tale
    Gilles: "what is a for you a reasonable carbon footprint in tCO2/capita/year, and for how long ?" The per capita footprint for most poor developing countries is well under 1 tonne, in many cases it is below 0.5 tonnes. Whilst the US has about 20 tonnes per capita. Even by ignoring climate change issues, it indicates that the US is wasteful and bloated, whilst others survive on a lot less. Even in comparison to Europe, the US is bloated and wasteful.
  49. The e-mail 'scandal' travesty in misquoting Trenberth on
    17 villabolo "It seems that the issue we're discussing here is one of precise phrasing as opposed to understanding of basic principles." Indeed; and anyone who has communicated by email - even scientific issues, let alone before the implications of FoI sunk in - knows they very can rarely phrase every point with legal precision. On the one hand, if you tried, you'd get nothing else done; on the other hand it's unnecessary when communicating with a colleague. (That's even true for discussions on blogs.) Critique at this level of pedantry is only really reasonable for folks who are outside the scientific debate and who are looking for trouble - rather than insight.
  50. How I lived through a carbon tax and survived to tell the tale
    Oh, & there's another document I just looked at which predicts the amount of energy China gets from coal will drop to only 30%-50% of total energy consumption-a prediction made by Chinese Energy Experts. Given that these same energy experts predict that total energy consumption will eventually be *less* than it currently, it does kind of wreck, once again, this notion that *only* fossil fuels are capable of reducing poverty. Another nation where this doesn't apply is Indonesia-a nation that could greatly benefit from a distributed generation framework based around a combination of Geothermal, Tidal, Wind & Solar energy. I doubt that Indonesia would need to build even a single coal or nuclear power plant in order to meet similar levels of per-capita energy demand as currently exists in the OECD.

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