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Gilles at 21:52 PM on 18 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
and last questions (sorry for not combining them in the same post) "so many clean & renewable sources of energy are available to meet all of our energy needs." could you please give me the quantitative amount of energy produced currently by these "so many clean & renewable sources of energy", and the growth rate you're expecting reasonably from them ? -
Gilles at 21:50 PM on 18 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
"whilst many nations in South America & Asia currently consume large amounts of fossil fuels, whilst still being gripped by massive poverty." Same question : which nation are you referring to, on a per capita basis ? -
Gilles at 21:49 PM on 18 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
Marcus : "I doubt it very much, given my own reading of history shows that the nations of Europe & North America had already reached extremely high levels of wealth *before* fossil fuels became widely available" Marcus, are you really serious ???? which epoch are you referring to , and how do you measure this "level of wealth" ? -
Gilles at 21:45 PM on 18 March 2011The True Cost of Coal Power
"If we include the coal externalities, it increases the levalized costs to approximately 28 cents per kWh, which is more than hydroelectric, wind (onshore and offshore), geothermal, biomass, nuclear, natural gas, solar photovoltaic, and on par with solar thermal (whose costs are falling rapidly). Suddenly coal doesn't look like such a good deal." maybe, but hydroelectric and geothermal are possible only in specific places, wind and solar are intermittent, natural gas and nuclear are also finite and have their own drawbacks and external costs (what is the cost of the three major nuclear accidents ?). And none of these can replace coal or other FF in non-power generation applications, which means that we need anyway a minimum amount of FF , which also means that it is very unlikely that we stop extracting them before they're exhausted, which also means that alternative energies will not REPLACE FF , but simply superimpose on them. -
Marcus at 21:31 PM on 18 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
Gilles-the criticisms of you are because you've made these claims-like a broken record-without providing a shred of evidence to back you up. Can you honestly show that the growth of First World wealth began *before* large-scale consumption of fossil fuels? I doubt it very much, given my own reading of history shows that the nations of Europe & North America had already reached extremely high levels of wealth *before* fossil fuels became widely available, whilst many nations in South America & Asia currently consume large amounts of fossil fuels, whilst still being gripped by massive poverty. Of course, even if you *could* show that consumption of fossil fuels was necessary to create wealth-in the *past*-that is certainly *not* true now that so many clean & renewable sources of energy are available to meet all of our energy needs. -
les at 21:21 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
636 Ryan "One aperture to receive light the second to radiate light" Ah, some more thermodynamics... ... have you met Maxwells Demon? -
TimTheToolMan at 21:00 PM on 18 March 2011What would a CO2-free atmosphere look like?
Well after all that I'm still unsure what you're saying. Are you saying that sensitivity has varied between 2.5C and 3.7C per doubling or something else? I dont know how much variation there is in sensitivity (nor do I think anyone knows or even CAN know with the data we have) but the following thought experiment might help in understanding where I'm coming from. Right back on topic and using my favorite method of looking at an extreme, what would the sensitivity be on a hypothetical hard snowball earth? For the first many doublings, it would be very low. Maybe even approximately zero. Only once CO2 levels have got very high would they have an effect and then it will jump hugely. What does this mean to me? Well it means that sensitivity depends on the climate's "state" and the CO2 level itself. Some states will be more sensitive than others. -
Gilles at 21:00 PM on 18 March 2011Sea level rise: coming to a place near you
"Currently we're on track to reach 1 meter sometime between 2070 and 2090 in business as usual (the A scenarios), and even most likely by 2100 in Scenario B1 (which assumes a major move away from fossil fuels toward alternative and renewable energy as the century progresses)." could you be more precise about what you mean by "being on the track?" with an exponential extrapolation with uncertainty, it seems that we're "on the track" to reach anything between 30 cm and a few meters. Please note a convenient feature of exponential extrapolations : any increase of uncertainty increases more the high values than the small ones, so increases both the average estimates and the "probability" of highest estimates. This has the logical consequence that the less we know, the more we're urged to act.Moderator Response: [DB] One of the logical consequences of reading a Skeptical Science post and the previous comments on the posted thread is to realize that the focus of this thread is on SLR impacts. Discussion of SLR uncertainties & the "pacing" of SLR is best conducted on one of the many other threads. Please use the Search function to find one of those other threads where, no doubt, an answer to your questions exists. Thanks! -
Tom Curtis at 20:23 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
L.J.Ryan @629, let us consider this step by step: 1) Consider the box as described, but without any lid. In this case all the light will reflect of the wall of the box and exit through the aperture where the lid was. Is that correct? 2) Now consider the case in which we place the lid on the box, but at an angle so that all light reflected of the lid will leave the box through some other aperture. In this case, the amount of light leaving the box through the lid will be half of that which enters, while the amount that is reflected by the lid and leaves through the other aperture will also be half of that which enters the box. Is that correct? Do either of these scenarios violate any law of thermodynamics? -
Tom Curtis at 20:11 PM on 18 March 2011What would a CO2-free atmosphere look like?
TimTheToolMan @90, the only study I have seen on the effect of changes in forcing on climate shows only slight changes (12% or less) over a range of values, but with much higher and smaller forcings shows a much higher (up to 33% higher) value. Taking the modern best estimate of climate sensitivity of 2.8 degrees per doubling of CO2, that means the minimum value is around 2.5 degrees per doubling, and the maximum around 3.7.
If we consider the minimum value only, that would indicate a fall in temperature after feedbacks of 14.6 degrees C for the total removal of CO2 from the atmosphere. That is likely way to small a reduction, as shown in the post above. However, it is a best case for Lindzen and shows him to have an error of 83% at minimum.
An alternative approach would be to compare climate sensitivities determined from geological data for warm and hot periods. As it happens, climate sensitivities determined for the LGM and for the Pliocene (cold and warm periods respectively) are very similar; as indeed are sensitivities determined using GeocarbSulf by Berner for the whole phanerozoic.
Regarding the "not at all subtle references", they are too subtle for me. All I know is that TTT are the initials of you chosen name.
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Rob Painting at 19:54 PM on 18 March 2011Examining the impacts of ocean acidification
Alan @ 30 - Sorry, my bad, misinterpreted your comment. Here's the FAQ page at EPOCA -
Tom Curtis at 19:02 PM on 18 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
Agnostic @15, the Climate Vulnerabilty Index developed by Samson et al (2011) was developed using 19 different climate indices. They developed two different models using contrasting subsets of these 19 indices to ensure that their results were robust. They then developed a model based on agricultural density as a second check on the robustness of their result. There results held regardless of which of the three models they used, showing that they are indeed robust. If that were not enough, we have Mapleleaf's Climate Vulnerability Index,based on 42 different social, economic and environmental factors, which shows a similar pattern of vulnerability.
You reject these indices of Climate Vulnerability because you mention certain environmental effects from climate change without checking whether or not they were used in developing the indices, and without purporting to show how including them would have changed the indices (ie, you use pure hand waving).
You also reject the indices because they do not show countries which have high populations but little arable land as vulnerable. One might suppose that such nations (Singapore for example) might get most of their food by trade, and hence are not reliant on local climactic conditions for their food; ie, that they are amongst the least vulnerable of societies to climate change. One might also suppose that, having read the paper (you did read the paper, didn't you) you would have noted the key factor in the CVI is the predicted change in factors effecting agriculture as the climate warms. Having noted that, you would presume that nations with high populations and little arable land in which the climate is not expected to change adversely are not that vulnerable.
Cherry picking a single datum as an excuse to reject a paper is not scepticism - it is avoidance.
Finally, Global Warming arises from the emissions of Green house gases, not by countries, but by cars, and trucks and power stations. They are the individual mechanisms of the economy serving the individuals in the economy. So the only honest comparison of GHG emissions is on a per person basis. Our credulity is indeed being stretched in this debate, but it is being stretched by those who maintain (as you are doing) that the 18.9 metric tons of CO2 per person in the US does less harm than the 4.9 metric tons per person emitted in China (2007 figures). Even this comparison underestimates the US contribution (as it would other western nations) because it ignores the extent to which high emission products in China have their final use in the United States.
Agnostic's claim that CO2 emissions are properly considered a feature of nations carries some absurd implications. It implies that Monaco and Lichtenstein should be allowed the same net emissions as the US in any international treaty. It implies that if a nation should divide in two, then their joint permissible emissions should double. Conversely, it implies that if the EU should ever coalesce into a single nation, its permissible emissions should be divided by the current number of member states.
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shoyemore at 18:30 PM on 18 March 2011Maximum and minimum monthly records in global temperature databases
Charley A #51 As I said above "the data are what the data are". This alternative look at the temperature record in the main supports the generally accepted views of climate science. -
Gilles at 18:15 PM on 18 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
I don't understand your criticisms. It's not ME who is saying that the countries consuming the most FF are the most resilient to natural hazards, it's YOU (or them..) : "They found the countries most severely impacted by climate change contributed the least to greenhouse gas emissions. It is quite striking that blue, less-polluting regions in the CO2 emissions map correspond to the red, highly vulnerable areas in the vulnerability map." This is a simple logical contraposition of the previous statement : countries with less CO2 consumptions are the most vulnerable < = > less vulnerable countries are those with the most CO2 consumption (which seems to be a rather obvious observation, BTW). Where is the problem ? -
Tom Curtis at 17:31 PM on 18 March 2011What would a CO2-free atmosphere look like?
TTT @88, from your deleted comment, it is clear that you did not intend to say that climate sensitivity is arbitrarily variable in time; but rather that its potential variability is governed by some other factor(s). What other factor(s) is that, and what is the range of sensitivities you believe to be operable? And (given the topic of this thread) how does it make a difference in determining the after feedback mean global temperature in the situation of zero CO2 in the atmosphere? -
alan_marshall at 17:29 PM on 18 March 2011Examining the impacts of ocean acidification
Another video Just in case you missed the reference at the bottom of my article, I recommend interested readers view the 10 minute video form the Catalyst program showing damage to foraminifera. The link is www.abc.net.au/catalyst/stories/s2029333.htm. -
Riduna at 17:23 PM on 18 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
I challenge the validity of this study on 2 grounds: 1. Accuracy of the vulnerability measure used and 2. Country contribution to global warming. 1. Vulnerability of people to climate change is best measured as sensitivity of their environment to the effects of global warming, which includes climate change nut also includes changes in ocean chemistry, sea level and water supplied from snow and ice. In other words it must be a measure of the ability of the human environment to provide those living in it with the essentials of life. This is very difficult to incorporate in an index and the CDVI very clearly does not do so. If it did, it would not show countries with highest population/hectare of arable land as having medium to low vulnerability. It would show them as being highly susceptible and vulnerable to the effects of global warming because that is what they are. 2. Global warming arises because of the emission of greenhouse gases, most notably CO2, by distinct socio-economic units called countries, permitted by the policies, practices and controls (or lack of them) imposed by their governments. It is a dangerous nonsense to assert that China contributes relatively little to global warming because it has a high population and therefore low per-capita emissions. Or that the USA contributes far more to global warming because of its much lower population. The fact is that in 2007 China emitted 6.538 and the USA 5.838 billion tonnes respectively, over 42% of global emissions of CO2 between them. Fig 2, shows countries of the world coloured on the basis of per capita emissions. It is therefore a nonsensical distortion, since it purports to show the relative importance of country emissions on global warming. It does no such thing. It defies credulity to assert that a thousand tones of CO2 released by China is far less harmful than a thousand tones of CO2 released by Australia. Yet that is what we are being asked to accept, even though both have precisely the same effect and make the same contribution to global warming. In Conclusion: by combining two defective measures to a map of the worlds’ countries, it is asserted that those contributing least to global warming are the worst affected by the results of global warming. Sorry, I do not buy it – nor dear reader should you! -
alan_marshall at 17:20 PM on 18 March 2011Examining the impacts of ocean acidification
Bringing politicians up to speed Over the past year I have enjoyed some modest success in a personal campaign in which I have written to all 226 members of the Australian parliament. Using old-fashioned mailed letters, complete with graphics and references, I have sort to contribute to their understanding of the science of climate change. The above article had its origin in a letter to parliamentarians about ocean acidification. It can be viewed on my web site at www.climatechangeanswers.org/campaign/OceanAcidification.pdf. I have received around 20 letters from politicians in response, and many of these can be found under Feedback Received. For example, the Hon. Malcolm Turnbull MP, former environment minister and former leader of the Liberal Party of Australia, wrote saying “I agree entirely with your concern about this issue”. I would encourage readers in the USA to do what they can to inform their representatives, particularly those Republicans trying to “repeal laws of physics”. -
alan_marshall at 17:14 PM on 18 March 2011Examining the impacts of ocean acidification
Rob Painting @ 29 I was not talking about a direct connection between atmospheric warming and ocean acidification. What I meant was that any projected emissions trajectory for CO2 that succeeds in keeping atmospheric warming under a given limit (currently 2 C) will also keep ocean surface pH above a limit. The correspondence between the two is therefore an indirect one, and does not take into account any change in the relative concentrations of CO2 and those greenhouse gases such as CH4 which do not contribute to ocean acidification. I still think the relationship is worth exploring, and that an internationally agreed target to limit ocean acidification is necessary. The FAQ section at EPOCHA is quite lengthy, Can you point me to the information you are referring to? -
K T at 17:01 PM on 18 March 2011Sea level rise: coming to a place near you
Sh*t, the whole of Singapore's going to be swamped. And THAT's where I live. -
L.J. Ryan at 16:52 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
scaddenp @633 360kJ is at minimum expended by the batteries. Surely you would accumulate more then 360kJ within the box. After all, the claim is reflected light (B from Tom Curtis's diagram) is twice the input. Why the discrepancy? So lets step it back, if your box was fully enclosed such all surfaces are reflective save two small aperture. One aperture to receive light the second to radiate light. Close the output while receiving 1W at the input. The energy accumulated within the box after 100 hrs is what, 360kj? If the first aperture is then closed does the box now contain 360kj of light? -
Rob Painting at 15:27 PM on 18 March 2011Examining the impacts of ocean acidification
Alan Marshall - We need to determine what this corresponds to in terms of a decrease in ocean surface pH. If we are to attempt to stop pH from falling below 8.0, I suspect a 2 C warming is too high IIRC this may be addressed on the FAQ section at EPOCA. Remember we are talking about 2°C of atmospheric warming, not the ocean. The decline in CO2 solubility from ocean warming this century is negligible. The effect on ocean stratification, on the other hand, could be dramatic. -
Tom Curtis at 15:24 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
RW1 @630, as it is difficult to carry on two discussions at once on the same thread, do you mind holding of on the discussion of the relevance of the light box until we have settled that it does not violate any law of thermodynamics? And to that end, do you agree that the light box does not violate any law of thermodynamics? -
TimTheToolMan at 15:21 PM on 18 March 2011What would a CO2-free atmosphere look like?
I see. Now Tom gets to dictate what I've "indicated" with a rubbish interpretation on what varying sensitivity means and I have no say in the matter. Real class SkS.Moderator Response: [DB] Your reply to Tom was deleted both due to the lack of substance and the devolution of the comment into childish behavior. When you start to personalize things you cross the line. Feel free to repost a reply to Tom, along with a substantive argument based on the peer-reviewed science. Show everyone why you are right. Merely disagreeing, and being disagreeable while doing it, adds no value to this dialogue. There are other venues for that type of behavior. -
2nd law of thermodynamics contradicts greenhouse theory
Keep in mind, everyone, that the gain of the box is 0.5, less than one, and hence a run-away feedback is not possible. Please see Does positive feedback necessarily mean runaway warming for details. Tom Curtis, I like your example. I did much the same thing on this thread earlier, except adding a value (which could be a column) of emissivity (0.612 for Earth, as measured), where your "C" was (1.0 - emissivity) * B, and "D" was emissivity * B. If you do that with 240 as input, the results are quite interesting, as per Trenberth 2009. -
alan_marshall at 15:11 PM on 18 March 2011Examining the impacts of ocean acidification
Ken Lambert @ 16 As far as I know, the transport of absorbed CO2 to the deep oceans is included in the models. The fact that surface pH is decreasing indicates that CO2 is absorbed from the atmosphere faster than it can be transported to the deep oceans. The model developed by the US National Centre for Atmospheric Research (Fig 1.) projects an end-of-century surface pH of 7.8, but it presumes a business-as-usual emissions trajectory. On the other hand, if the world urgently makes serious efforts to constrain emissions, the outlook is not quite so bleak. The UK Department of Energy and Climate Change (DECC), in drafting the UK Climate Change Act of 2008, commissioned a consortium of experts led by the Hadley Centre to model the trajectory for ocean surface pH under their ambitious “2016 4% Low” scenario. If annual global emissions were to peak in 2016 (developed countries sooner, developing countries later), and then decline in line with the Global Commons Institute’s Contraction and Convergence formula, the atmospheric concentration of CO2, as a result of cumulative emissions, would peak around 2050. DECC projects that under this scenario that by 2050, "the biological pump and deep ocean transport of carbon" will remove CO2 from the upper layers of the ocean as fast as the upper layers absorb CO2 from the atmosphere, resulting in pH levelling off at 8.0. I agree with their reasoning. Once atmospheric CO2 peaks, ocean surface pH can be expected to stabilise, even though the ocean average pH will continue to increase until the atmosphere and ocean are in equilibrium. I am pessimistic about the chances of securing an international agreement that would see global annual emissions peak in 2016. Nevertheless, I am a supporter of the Contraction and Convergence solution, and believe we need to start focussing politicians on setting a target to limit ocean acidification. Copenhagen secured an agreement on a target of limiting global warming to 2 C. We need to determine what this corresponds to in terms of a decrease in ocean surface pH. If we are to attempt to stop pH from falling below 8.0, I suspect a 2 C warming is too high. This is something for readers may like to investigate. -
scaddenp at 15:04 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
1J/s for 100 hours, thats 360kJ accumulated. Of course your torch also absorbs energy so guess that is going melt at some point. RW1 - this lightbox example is simple demo of how not to make inappropriate inference about energy from energy flux through different surfaces. Do you agree with light box as TC has set it up? -
L.J. Ryan at 14:35 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
e @631 Let's assume the flashlight radiates with a 1W bulb for 100 hrs. How much energy is contained within the box at the end of a 100 hrs? How long to accumulate a gigawatt? -
Bern at 14:01 PM on 18 March 2011Sea level rise: coming to a place near you
Thanks for the article, Daniel. I hadn't seen that particular site before when searching for sea level rise mapping. For folks in Australia, I highly recommend the OzCoasts mapping found here. It's based on much higher-resolution elevation data than the Uni of Arizona mapping, so gives a more accurate picture for the selected areas of Australia that have been mapped. Having said that, they only look at up to 1.1m of sea level rise, as their "high level" SLR. Their interface kinda sucks, too, for people used to Google Maps style pan & zoom interfaces! I think the mapping at this site is not bad, also. It lets you look at SLR up to +60m (the *real* worst-case scenario, though it'd most likely be centuries away) -
2nd law of thermodynamics contradicts greenhouse theory
LJ@629>However, energy can NOT accumulate within the box, This is not correct. Don't forget that the flashlight is continuously outputting radiative energy (converted from energy stored in batteries). If the energy cannot escape, then yes of course the radiative energy accumulates in the box. Otherwise you would violate conservation of energy, because if the flashlight is outputting energy and it does not escape and it does not accumulate, then it must have been destroyed. It would of course stop accumulating after the flashlight runs out of battery or shuts off. Fortunately in the earth system analogy our "flashlight" will not run out of juice for a very long time. -
RW1 at 13:44 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
Tom Curtis (RE: 615), "By simplifying the situation, ie, by getting rid of any concerns about convection and light absorbed by the atmosphere etc, we should be able to raise any issues you have with the consistency of the GHE with the laws of thermodynamics without getting hung up on trivia. Do you agree?" No, I don't agree that it is trivia. Understanding the energy flows relative to the radiative balance is absolutely fundamental to the entire GHE and ultimately surface temperatures (i.e. how much surface emitted radiation is coming back from the atmosphere and how much is passing through). All I'm saying is latent heat and thermals are just redistributing energy around the thermal mass of the system - mostly from the tropics to the higher latitudes. The bulk of this energy condenses to form clouds, weather systems and returns as precipitation. Any amount of it that ends up radiated out to space is equally offset at the surface by a lesser amount returning, which cools the surface. All the energy flows are constant, thus this effect is already accounted for in the 396 W/m^2 emitted at the surface. -
L.J. Ryan at 13:33 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
Tom Curtis @626 "Do you have any problems with that?" As I said A=C, so with that we agree. However, energy can NOT accumulate within the box, B can not equal 2A, no way can't happen. Your scenario is a light/energy doubler. If you change your filter to reflect 75% what happens? Take it further, enclose a flashlight within a completely and perfectly reflective box, at what point is there infinite energy therein? -
Rob Painting at 13:11 PM on 18 March 2011Maize harvest to shrink under Global Warming
John D This study merely benchmarks the average response of the average variety averaged out over the entire period studied, it tells us nothing about how plant productivity is advancing, or not Indeed, for these trials, but given that these programs have been going on for many decades, and the 30°C mark has been identified as a limiting factor. It doesn't bode well for the future. -
Rob Painting at 13:03 PM on 18 March 2011Maize harvest to shrink under Global Warming
John D @32 - What happens in a laboratory enclosure is often quite distant from what occurs in the field. John D @ 35 - But if you want to be pedantic, then a trial plot, or a paddock used for a full blown trial meets the criteria of a laboratory being a place where scientific research and experiments are conducted. Seems you can't decide exactly what you mean. -
Tom Curtis at 12:57 PM on 18 March 20112nd law of thermodynamics contradicts greenhouse theory
C Truth @627, the ideal gas law is included in atmospheric physics in calculating the lapse rate, as shown in this university lecture, and as explained by me very briefly in 563 above. It is also included in analysis of convection, but as convection in the atmosphere is what establishes (on average) the lapse rate, that is saying the same thing. It follows that any explanation of the green house effect that incorporates the environmental lapse rate already incorporates the gas law. As previously discussed in this thread, the standard theory of the greenhouse effect incorporates the lapse rate as an essential element of the theory. So, yes, understanding the gas law can provide insights into the greenhouse effect, and those insights were discovered decades ago, and are the basis of the modern understanding of the greenhouse effect. -
Tom Curtis at 12:43 PM on 18 March 2011What would a CO2-free atmosphere look like?
TTT @79: First, Lindzen did not just arrive at the figure by a different calculation. He got it wrong. Even if we suppose he was determining the value by using the law value for climate sensitivity (0.5 degrees per doubling) that he accepts, despite the fact that it is contrary to all the evidence, then he still significantly understates the relevant cooling. Second, the idea that climate sensitivity is inconstant in a range between 1 and 4.5 K per doubling is just nonsense. The net greenhouse effect on Earth including feedbacks is at least 33 degrees C. If climate sensitivity varied in the range you indicate, then that net greenhouse effect should vary in the range from 11 degrees C to 49.5 degrees C. In other words, the mean global surface temperature should vary from -8 degrees C to 30.5 degrees C without any changes in forcing. Given the observed range of natural variation in the Holocene, even if we assumed (contary to fact) that they were unforced, the range of variation of climate sensitivity would be limited to plus or minus 0.05 degrees C. Of course, climate sensitivity probably does vary depending on the lay out of the continents, and as a function of MGT. But that is hardly heartening to deniers, because studies of such variation show we are currently in a trough of low sensitivity, and that increasing temperatures will probably result in increasing sensitivities. -
Chris Colose at 12:43 PM on 18 March 2011What would a CO2-free atmosphere look like?
TTTM, I have no idea why you are still arguing this. First off, a “no-feedback” sensitivity is useful in that it provides a baseline from which to compare the impact of internal feedbacks on the system (in fact, defining this reference system is a central aspect of feedback analysis). What this ‘reference system’ is depends largely on the application of interest. When we traditionally talk about positive and negative feedbacks, they are ‘positive’ or ‘negative’ relative to a blackbody reference system that restores radiative equilibrium via the Planck function when something like CO2 or solar is perturbed (largely because this is well understood). For someone interested in soil moisture and vegetation changes in global warming, it might be more useful to let other variables freely change, define this as the reference system, and define the feedback as just those processes of interest. If you change the reference system, you also change the feedback. This is an important point and not just semantical. But Lindzen was asked a straightforward question: would Earth be hotter or colder with no CO2? To his credit, he managed to get the sign right! But he threw in his own quantitative estimate, and the answer he sold implied both a reference system and a feedback. When you’re talking to policy makers, they are interested in the real world, and the real world is a reference system plus feedbacks. He was not asked “how would the temperature change if everything in the world stayed the same and we removed CO2,” in which case he would have still been wrong, just less so. If he wanted to give a no-feedback answer, than he should have made that caveat in the testimony, in which case I would still have made this post for educational and thought-experiment purposes anyway. But you are simply arguing that Lindzen is allowed to make up whatever number he wants, whether it be 2.5 C or 250 C colder. That’s not how science works, sorry. -
Eric (skeptic) at 12:32 PM on 18 March 2011Sea level rise: coming to a place near you
ok thanks, I will read through the other threads. Minor note on browsing (please delete this comment): the images of the impacts are stored at 900-1000 pixels wide and downloaded in that resolution then scaled by my browser to 500 pixels. The download was a bit slow on my connection so if they could be stored around 500 pixels wide that would reduce download time by about 4xModerator Response:[DB] Sorry for that, Eric. I had to compromise with what to show or not show for the exact same reason. When I created the original files, I used cartographic license to decide the optimal scales to visually depict each area affected by SLR. Too small a resolution would have compromised many a picture.
Anyone can use the linked mapping program to look at any location in the world themselves (for those feeling left out because I didn't choose their city). It's actually pretty simple to use.
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TimTheToolMan at 12:24 PM on 18 March 2011What would a CO2-free atmosphere look like?
"defending such an incorrect answer is indeed "complete hogwash"." Somewhere along the line, I am suddenly defending Lindzen's answer. This is typical of AGW arguments. If they cant argue their point successfully then they turn it into a point they CAN argue against successfully. MY point about AGWers criticising Lindzen is that their criticism is largely of Lindzen answering without feedbacks and this criticism is invalid. THE answer (whether Lindzen's or anyone else's) of CO2 warming in the atmosphere irrespective of feedbacks is a perfectly valid answer in its context. -
johnd at 12:19 PM on 18 March 2011Maize harvest to shrink under Global Warming
Rob Painting at 11:09 AM, if you are unable to differentiate how the development of new varieties of plants involves trials that range from those in laboratory enclosures, through trial plots to full blown field trials, then you need to research more. But if you want to be pedantic, then a trial plot, or a paddock used for a full blown trial meets the criteria of a laboratory being a place where scientific research and experiments are conducted. This study provided results that are the averages of about 20,000 separate trials conducted over the period 1999-2007. The yields provided from individual trials ranged from about zero to 15mg/Ha under the Optimal conditions, and from about zero to about 8mg/Ha under Drought conditions. That is a considerably wide range. I would suggest that any projections about how maize, or any plant variety, may perform in the future should be based on those varieties that out perform the average. This study merely benchmarks the average response of the average variety averaged out over the entire period studied, it tells us nothing about how plant productivity is advancing, or not. If it had divided the period in half, we might have been able to see how plant technology is advancing through later development of new varieties, but it doesn't, so the study offers nothing to indicate whether optimism or pessimism is the most appropriate response. The whole premise of the study is based on the status-quo remaining so. If anyone wants to remain up to date as to how any plants are likely to respond to changing conditions, then they should focus on the varieties that progress through trials to commercial release and analyse what data is available from the commercial breeders. Then perhaps one has a yardstick that is more relevant, and more up to date than some academic study based on averages. -
What would a CO2-free atmosphere look like?
TimTheToolMan - The amount of warming CO2 creates is a very important question. It's unfortunate that Lindzen's answer makes absolutely no sense given known physics, data, and constraints - and given the observations and the physics, defending such an incorrect answer is indeed "complete hogwash". -
TimTheToolMan at 11:53 AM on 18 March 2011What would a CO2-free atmosphere look like?
"That said, defending Lindzen's answer as just as valuable "as any other answer" is complete hogwash." I see. And so the amount of warming CO2 creates in the atmosphere is not useful to know even though its essential to understand that before moving on to understanding the feedbacks? Its ALL hand waving Dan and Chris. -
Eric (skeptic) at 11:43 AM on 18 March 2011Sea level rise: coming to a place near you
Blowing up the sea level projection:
it looks like there should be close to 5 cm/decade, but we are only measuring 3 cm/decade.Moderator Response: (DB) This thread is about visualizing the impacts of sea level rise; debating actual SLR vs projections is discussed on other threads and is off-topic here. Thanks! -
Chris Colose at 11:40 AM on 18 March 2011What would a CO2-free atmosphere look like?
The reason I created this post was not just to address Lindzen, but to create some thinking about broader issues in planetary climate. In a PRACTICAL sense, these questions might not be important right now on Earth, but they are important for example to astrophysicists exploring the limits of habitability. This is important as many new planets continue to be discovered (e.g. Gliese 581 g), since the extrasolar planet database is now at ~500 new worlds, a few of which could potentially support liquid water depending largely on their atmospheres. These questions are also important for considering some of the big questions in Earth's past, such as getting into and out of a snowball, how to offset a faint young sun, etc. While having zero CO2 sustained in the atmosphere might be very hard to do, it is a type of extreme case with much of the same physics operating as other extreme cases, like a 30% fainter sun. In the snowball deglaciation problem, we consider the opposite spectrum in which a substantial fraction of the atmsophere is CO2. This is also important for considering the evolution of Mars or Venus. While climate science on the blogs does not generally talk about these things, and there's not a heavy denial thinktank attacking them (because how Venus evolved doesn't effect fossil fuel industries or the fear of governmental control), there's still many scientists out there who do think about them. That said, defending Lindzen's answer as just as valuable "as any other answer" is complete hogwash. It doesn't matter if you double CO2, make an atmosphere of 90 bars of CO2, or think about a 50 ppm only atmosphere. The point is to understand the underlying physics, to get our understanding as close to reality as possible, and this does not involve making things up. It's perfectly fine to consider exotic cases in modeling, but you want to be self-consistent in obeying physical constraints (e.g., you can't remove some 10 C of the greenhouse effect and hope to keep the water vapor and ice the same). Even with compeltely neutral feedbacks, Lindzen is still off by a factor of 2-3. It is also legitimate to criticize the efforts being done so far constructively, but saying that it's all fantasy just because we are dealing with something you may not be familiar with, might be "too far out" from modern Earth, or whatever other lopsided rationale you build up displays great ignorance into the field of planetary climate. -
Daniel Bailey at 11:32 AM on 18 March 2011What would a CO2-free atmosphere look like?
Hypothetically, one could say that without hands to wave, hypothetical "skeptics" would be incapable of communication. Hypothetically. One could also posit that without CO2, communication might well be impossible. Without a seance, anyway. This conversation only hypothetically happened anyway. Electrons being virtual. The Yooper -
Albatross at 11:21 AM on 18 March 2011What would a CO2-free atmosphere look like?
Tom Curtis @77, You said it better than I could. TTT, seems to be missing the entire point of this exercise. And TTT, does not understand that it is not about what I or you "like" or not, it is a question of what the physics state/dictate. The physics state that Lindzen is wrong, but I understand that being a "skeptic" means that one has to concede nothing and rarely, if ever, admit fault. Here we have yet another example of that, this time courtesy of TTT. -
TimTheToolMan at 11:20 AM on 18 March 2011What would a CO2-free atmosphere look like?
@Tom "So perhaps your "fantasy figure" is better than Albatross's "fantasy figure" for you, but only if it is your intent to deceive." I'm not the one who feels strongly about a certain "answer" to the question. I doubt sensitivity is constant and therefore whether its 1K, 3K or 4.5K per doubling right now isn't as important as some say it is. I do feel strongly about criticisms leveled at people because they quote an answer calculated in a different way. -
Rob Painting at 11:09 AM on 18 March 2011Maize harvest to shrink under Global Warming
John D -What happens in a laboratory enclosure So now an African field is a laboratory?. Please get serious. The point of my last comment (which you clearly do not understand) is that these trials are simply a continuation of earlier ones, where hardier breeds have been identified. The study analysis is therefore of the hardiest known breeds at the time. I expected you would actually understand what selective breeding is, before commenting here. My mistake. -
Paul D at 11:02 AM on 18 March 2011Sea level rise: coming to a place near you
piloot. OK add 5m to sea levels then add the storm which would add another 5m. The point being is that you have to think in terms of mean or average increases, then add your highest yearly tides, storms etc. The result is that flooding occurs more frequently. -
TimTheToolMan at 10:54 AM on 18 March 2011What would a CO2-free atmosphere look like?
"Instead of ROFL, you might want to try and engage in some actual science. And to be quite honest, your post @75 makes no sense whatsoever. " I'll spell it out for you then. You say you cant ignore feedbacks because they DO exist and hence ignoring them would not make sense when deriving an "answer" but along precisely the same lines of reasoning you cant ignore CO2 either because CO2 DOES exist. But of course you can ignore any effect you want and both answers are perfectly valid within the context of the assumptions made on their calculation. Just because you dont like it, doesn't make it wrong. The ROFL part is because you're insisting the answer with feedbacks is more valid than the answer without when in fact neither answer is valid in any practically useful sense.
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