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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 105701 to 105750:

  1. Isn't global warming just 2 °C and isn't that really small?
    Re: adrian smits (32) I just spent a half-an-hour reading your latest comment, all of your previous comments and the excellent responses that others (and a few by myself) have offered you in response (ironically, I believe I have replied to you more than any other visitor). I have to ask, did you read any of those responses? If so, did any of them make sense? Because after reading this comment, I conclude that the only part you actually are correct on is this:
    "I'm sorry folks but I just don't get it."
    And it's not because you weren't offered excellent advice from others here much smarter than me (I won't name them to avoid swelling their egos, but they are legion). So, to recap:
    1. You're wrong about the DMI, again 2. You're wrong about the accuracy of the arctic temperature records 3. You're wrong about UAH 4. You're wrong about 6 month trends having any meaning relative to data encompassing many decades 5. You're wrong about _______ (fill-in the blank with whatever I've missed)
    I won't bother to provide you with any sources to substantiate anything I've said (go back and read all of the responses to your previous comments; the answers with sources are all there); you won't read them anyway, so why should I waste my time? The Yooper
  2. What should we do about climate change?
    “What should we do about climate change?” I don’t know what we should do about climate change. I do know what we can do to reduce greenhouse gas emissions. 70% of greenhouse gas emissions come from our use of fossil fuels. Of this, 30% is from electricity generation. If electricity is cheap enough it will substitute for gas for heating and oil for transport. Clean electricity, if cheap, could reduce Australia’s greenhouse emissions by 50%. That is just by implementing low-cost, low-emission electricity. The cheaper electricity is, the faster it will displace fossil fuels for heat and transport The cheaper electricity is the faster it will be adopted in the developing world. That will save millions of lives per year, improve their standard of living and many other advantages. If the under-developed and developing countries can implement cheap clean electricity instead of cheap, dirty electricity, world greenhouse gas emissions will be reduced much faster than if they have to go through the fossil fuel stage. Therefore, the most important thing we, in the developed countries, need to do is to focus on is implementing lost cost, clean electricity. We will not do that while we allow unfounded beliefs to dictate policy. Raising the cost of electricity through pricing carbon and mandating and subsidising renewable energy is exactly the wrong policy if we want the world to take the fastest path to reducing greenhouse gas emissions.
  3. Isn't global warming just 2 °C and isn't that really small?
    I'm sorry folks but I just don't get it.You all claim the arctic has warmed 5 or 6 degrees but the DMI record above 80 in the high arctic shows over half a degree of cooling in the summertime over the last 50 years.Isn't that when most of the melting is supposed to be happening up there.This cooling is in total disagreement with the GISS record by the way,which kind of brings the arctic temperature records into some disrepute.Now I also read the Roy Spencer article and my take on it was a total increase of 1.7 degrees with a c02 doubling .I just read it and He said some changes where made after it was posted so there might be some misunderstanding there.As far as the UHA near sea surface temperatures go they have cooled close to 8 tenths of a degree in only 6 months. That is more cooling than any 6 month period in the last decade. This is serious cooling and could lead to serious problems with crop failures if it lasts much longer!
  4. Philippe Chantreau at 10:27 AM on 29 October 2010
    The 2nd law of thermodynamics and the greenhouse effect
    Much ado about nothing. You're picking on words. I do not believe it matters that much how the problem is sliced, as long as all the meat is still there. I see no evidence that climatologists lost or added any. Picking on the wording used to communicate the ideas to a larger public is just rethoric. I have not followed the back and forth exchanges, in which it appears that G&T somewhat recant on the language quoted by KR above. That quote is pretty clear and indeed well summarized by the punch line used to sell the original G&T "paper" to skeptics. I have only so much time and will certainly not spend it on G&T's wirtings subsequent to their first paper, when I could play with my daughter or practice my trumpet instead (that choice is a no brainer). This is not worth anywhere near that much attention. I'm done here.
  5. IPCC were wrong about Himalayan glaciers
    I'm glad to see, at least in the Intermediate version, that WG1 and WG2 are differentiated. There exist those that would invalidate all of WG1 on the basis of, effectively, a typo in WG2. The Yooper
  6. Medieval Warm Period was warmer
    There is no such thing as "skeptical research" as you used the term. There is only research applying normal 'sceptical' analysis and review type science. Funding is or isn't granted on the basis of dribs and drabs (very big dribs and drabs for multi purpose satellites) of funding allocated to projects on varous criteria. If someone wants to write a paper, they're best off using commonly available data with good methods and r.o.c.k. s.o.l.i.d maths, physics and stats. And then there's the language. If you want scientists and science at large to take notice of your work, get the language right. Claiming that you've overturned the whole of physics of gases or the thermohaline circulation model is not the way to et a hearing. Use standard "we did this, then that. when we analysed the data, this is the result." Dry as dust language backed up by impeccable observations and calculations is the only way. If the claims really are spectacular, save the hyperbole for the press release.
  7. What should we do about climate change?
    Re: daisym (103) Apologies for not interpreting your question(s) correctly. I'm glad you found some of what I wrote of value. Let me try again:
    "How much of a potential global temperature increase was averted by using wind and solar devices?"
    Not having run the numbers or even seen the numbers run, I couldn't tell you with any certainty (KR, Marcus, JMurphy, Neil King or kdkd could probably tell you off the top of their heads). But given the magnitude of the fossil fuel releases compared to the extremely limited (as yet) negative CO2 footprint of green energy tech like wind, tidal or solar, the CO2/temp "savings" thus far have to be microscopic (i.e., lost in the "noise" of the standard fluctuations of temps over time).
    "This is what I was lamenting in my earlier comment. Government is heavily subsidizing wind and solar, but what effect will use of wind and solar have on global temperature? Is this giving us enough "bang for the buck"? Will it stop the increase in global temperature, or merely slow it down? We're not being told. I doubt that anyone has done the calculations, else why haven't we been told?"
    I would have to disagree with you slightly on your first point here: government expenditures/subsidies of green energy tech is a drop in the bucket compared to that spent on the fossil fuel industry. You must remember to include mineral and liquid hydrocarbon lease costs (which are a fraction of the true value of the resource) into the equation. If fossil fuel interests had to pay commercial market acquisition costs for those green energy tech would begin to look much more cost effective. But I prolong the inevitable, sorry. This part sucks, but here goes: Lets say, in a perfect world, we're able to convert over 100% of fossil fuel derived CO2 emissions to green energy tech (hang the details, a thought experiment). So we replace the 31.8 gigatonnes of CO2 (2008 data) injected from fossil fuels with...zero CO2. Balance restored, right? Not quite. Due to the built-in feedbacks in the pipeline (that darn thermal mass of the ocean getting redistributed again), the world will continue to warm for a while (25 to 50 years timeframe). With zero fossil fuel derived CO2 inputs, about another 0.6 C on top of the 0.8 C already achieved. CO2 concentration levels will then probably level off in the 440-450 PPM range, ~ 2100 or so. Long term feedbacks (as there is no paleo comparator for the CO2 slug we've injected into the natural carbon cycle) maybe add another 0.5 to 1.0 C, for a grand total of 1.9 to 2.9 degrees C (referenced to preindustrial levels). So under a perfect-case scenario, with the economy magically transitioned to a zero-sum fossil fuel CO2 game, we will get additional warming roughly equal to what we've already received. Or more. So why bother? Unless we pull out all the stops, the odds of a methane hydrate release in the Arctic go from an already non-zero chance with the minimum warming in the pipeline to a near-certainty of another 30 to 50 years of Business-As-Usual. So we either pay the piper now, and suffer not immodestly economically, but we all survive. Or we go off the cliff: BAU for 30-50 years puts us on a trajectory, counting a likely methane hydrate release (which has happened before) of 800 to 1,000 PPM (timeline unknown). But a global temp increase of 5 to 7 degrees C (estimates vary, but the effects of that are explained well here). And a good chance most of humanity ceases to exist. Sorry to be alarmist. But if you were in the World Trade Center in New York the day the planes hit, what would you have done when management said that there was no cause for alarm and not to worry? Would you have gone about your regular routine or would you have exercised caution and immediately vacated the premises, just to be safe? Obviously, hindsight colors this analogy. But it still holds for what we face today: Deniers and delayers, some with vested interests and some not, tell us everything is fine and even if not, that we should wait before acting hastily. Some in the World Trade Center acted hastily...and lived. If we wait until we're sure, due to the delays, it would be like being in a military conflict and waiting until you can see the sniper picking off your men before opening fire in return. In that case, you're already dead. The difference, also, between the weight gain analogy from my earlier post and what we face with climate change is this: with an appropriate response, an individual can make a dramatic change in their weight. In the case of our lifestyles and the world fossil fuel based economies, all of humanity now has to "go on a diet". So why does no one in government want to discuss this? Good question. Probably because they fear the same reaction you are experiencing right now: utter disbelief. It is one thing to understand the various bits and pieces of the physics and mechanics of climate change. It is completely another thing altogether to synthesize it into one cohesive whole as Hansen has done. Well, I've probably done enough damage for one day. The Yooper
  8. IPCC were wrong about Himalayan glaciers
    I am afraid both the current versions of "Basic" and "Intermediate" need some revision. I think that the issue of the Himalayas proper and the issue of the central Asian highlands including the Himalayas should be distinguished. I have made some comments on the blog article of "Himalayan Glaciers, Wrong Date, Right Message. I am tempted to write clarification myself, but, regrettably, I cannot promise it. At least, Kehrwald et al. (2008) should not be used as a reference for the issue of population who depend on glaciers. Kehrwald et al. just quoted from IPCC AR4 WG2 (including the errorneous "prediction") and Barnett et al. (2005) about that. Kehrwald's paper seems to be a good reference about the mass balance of certain glaciers they studied. Also, the word "IPPC" in the title should be "IPCC".
  9. What should we do about climate change?
    mc The in situ processes that Shell and also Chevron are using avoid many of these problems. The projects are long term development. The big problem is energy. The Shell process requires several years of heating before producing wells can start pumping out oil. Did you google "SASOl" South Africa obtains about 40% of their liquid hydrocarbon forn coal using the Fischer-Tropsch process. Exxon Mobil was about to bring a heavy oil field into production in the Orinico basin a few years ago until Hugo C wanted 51% of the action. They walked away and sued Hugo for a few billion dollars. By walking away, they avoid sharing trade secrets. If Hugo got his hand on these he would sell them to the Chinese. Google "SAGD" and "toe to heel injection" These are newer methods for recovering heavy oils.
  10. Climate sensitivity is low
    Berényi Péter makes many interesting remarks, but I am afraid his arguments are incoherent in the sense Stephan Lewandowsky wrote here in the areticle The value of coherence in science. I admit that my own arguments are sometimes incoherent, but I then also admit that I am not confident about what I say. I read his comments on the blog article here The 2nd law of thermodynamics and the greenhouse effect. Though it may be different from his own summary, I think he effectively say that the way how to apply thermodynamics to the actual climate of the earth is not very sure on one hand, and that he can say something certain about the climate of the earth by applying the maximum entropy production (MEP) principle, that is an advanced part of thermodynamics, on the other hand. Also, in his recent comment in thread on the 2nd law, he suggested that the average temperature at the surface (the surface between air and sea or between air and land) may not be a good measure for thermodynamic discussion of the climate system. On the other hand, the concept called "climate sensitivity" conventionally by climate scientists is defined in terms of the average surface temperature. It may be coherent from his position to say that the "climate sensitivity" is not a well defined quantity and we cannot say anything certain about it. I do not think he can be sure that the value must be low.
  11. Medieval Warm Period was warmer
    A couple of questions: 1 - The map appears to have around 3500 Pixels. I can easily understand how it is possible to get accurate data for today, but I am unsure how anybody can seriously expect to produce a credible version using 'over 1000 tree-ring, ice core, coral, sediment and other assorted proxy records'. That would be enough to cover 1/3 of the map (assming the proxies were remotely accurate). Where did the other "data" come from ? (Please don't tell me it was extrapolated from the other points!) 2 - It is often argued that it is impossible to get funding for "skeptical" research. Who are "the powers that be" who decide which research is to be funded or not ? In the US I assume it primarily is 'big business' and in Europe, Government, is this correct ? How did a bias creep in ?
  12. Skeptical Science Firefox Add-on: Send and receive climate info while you browse
    A very nifty tool. I'm not sure I'll find a way of using it (until playing with it, I'd forgotten how narrow Skeptical Science's remit is) but it seems very well done - although I did get a freeze when trying to close some tabs that Firefox created when I tried to close Report windows. I didn't think of the obvious - just click anywhere except on the Report window. (Firefox 3.6.11, Windows XP.) Some more nitpicks. 1) One of the arguments has a misspelled 'exaggerate' (only one g). 2) Three choices are offered for categorizing submissions: 'Skeptical', 'Neutral' and 'ProAGW'. I can guess what the first means (Skeptical Science uses 'skeptic' to mean 'denialist') and the second is probably meant to be half way between the first and third choices but what does the third mean? Does 'ProAGW' have an established meaning here at Skeptical Science? To an outsider, it's an unfortunate term because it is a valid description of the attitudes of various groups on both extremes of the 'debate', both denialist and alarmist. I suspect that it is supposed to mean 'More or less convinced by the "consensus" position as presented by the IPCC'. Unless the term is well-established here (in which case, ho hum), wouldn't something like 'consensus' or 'AGW is real' be less confusing?
  13. What should we do about climate change?
    Argus #97 I think it’s admirable that Denmark has such ambitious goals concerning renewable energy, and if they achieve these goals it will be a lesson and an example for many countries. Besides, it is also a smart strategy, as it will make Denmark eventually independent of foreign energy suppliers (and we don’t know what is going to happen on the energy market, but we can be sure it is going to be a bumpy ride). However, I am wondering if the deployment of renewable energy will have any lasting effect in the battle against climate change. The fossil fuel that isn’t consumed in Denmark will not remain in the ground. It will be burned elsewhere. So that is basically my statement: Climate change can only be fought by stopping new carbon from entering the carbon cycle (or by removing the same amount of carbon that is added to it). Deployment of renewable energy will -possibly - slow down the consumption of fossil fuels, but it will not stop the burning of fossil fuels. And therefore it can at most delay, but not avoid catastrophic global warming. Of course, even delaying AGW can be a crucial part of the solution. But it cannot be the whole solution.
  14. What should we do about climate change?
    daisym - If you want to compare power sources and their temperature increases, you might want to look at the Waste heat vs greenhouse warming page. Long story short: the CO2 emitted by burning carbon fuels causes ~100x the warming that the energy released does, 2.9W/m^2 versus 0.028W/m^2. So every MW converted from carbon fuels leads to reducing 100MW of warming. In terms of temperature, the current 15TW produced and used in all countries will (at equilibrium) warm the world by 0.015°C to 0.034°C. Compare that to the 1.5-3.5°C (depending on your estimate of climate sensitivity) from the CO2 we've put into the air so far. Further discussion on this, however, should probably take place on the Waste heat vs greenhouse warming page.
  15. What should we do about climate change?
    #98: "a great many bases for wind generators the last time I flew over Texas." Texas is rapidly converted the land above old, depleted oil fields into wind farms. See the wikipedia article for some history. Table 3 here shows that electrical generation using wind power in Texas may be as much as 500% of electrical consumption.
  16. What should we do about climate change?
    RE: Daniel Bailey #72 Thank you for responding. What you wrote makes sense. I understand that we won't see temperatures coming down very quickly because of the reasons you explained. The main question I was asking was: "Energy is being generated by wind and solar devices. As a result, no CO2 was introduced into the atmosphere from energy produced by these devices. If the equivalent energy had been produced from carbon fuels, then "X" tons of CO2 would have gone into and warmed the atmosphere. How much of a potential global temperature increase was averted by using wind and solar devices?" This is what I was lamenting in my earlier comment. Government is heavily subsidizing wind and solar, but what effect will use of wind and solar have on global temperature? Is this giving us enough "bang for the buck"? Will it stop the increase in global temperature, or merely slow it down? We're not being told. I doubt that anyone has done the calculations, else why haven't we been told? If a dietician can estimate the effect of 100 calories per day (either added to or removed from the diet) on a persons weight, I'm hoping that climate scientists can do the same thing regarding the net change in CO2 (and thus temperature) resulting from generating power by wind and solar devices, instead of carbon fuels.
  17. What should we do about climate change?
    #95: "There are about 10-15 trillion barrels of unconvential oil which are heavy and extra heavy crude oils, tar sand and oil shale." Plans for oil shale recovery come and go whenever there is a price shock. Oil shale production is characterized by high front-end capital and operating costs and long lead times between capital investments and operating revenues. The potential for changes in economic conditions, energy markets, capital markets, government leadership and policies, and public support for oil shale projects, imposes greater risks than many other energy project investments. -- Oil Shale Roadmap, 2004 That problem is anathema to an oil industry dogged by price and demand concerns. Nor is oil shale a 'free in Nature' as you specify in #95. The extraction process is an environmental mess, especially involving the water requirements: Current water supply from the Colorado River Basin System is likely to be adequate to support the initial phases of oil shale industry development. However, the quantity of water required for a large-scale industry, producing 2-4 million barrels per day or more, could present a significant hurdle. -- same source (And that's what keeps this on topic -- warming climate means disruptions to water supplies.)
  18. What should we do about climate change?
    Eric Those folks are so filthy rich that they can afford their own power systems and many have back up power. After all you can't have all that really expensive wine in cellar and steaks in the freezsr go bad. Or no power for the heated pool and sauna.
  19. What should we do about climate change?
    Peak oil only refers to oil that can be recoverd by present convential methods. These are (1)flow from the reservior under natural pressure,(2)pumping, (3)water flodding and (4)gas injection suchas CO2. At the temperature and pressure in the reservor CO2 can be a super critcal fluid which has good solvent power for many materials. A super critical fluid has a density greater than the gas phase but less than the liquid phase. The CO2 on Venus is supercrical fluid not a gas. The critical temperature and pressure for CO2 31.1 deg C and 72.9 atm, resp. Above 31.1 deg C CO2 will not form a true liq phase no matter how much presssure is applied. The oil coming out of the damaged BP well in the Gulf of Mexico was flowing at pressure of ca 3000 psi iirc. It probably a real good idea to get as much of this high pressure oil out the reservor. An earth quake that cause release of this deep oil would be a true catastrophe and there would no easy way to stop it. There is nat seepage in the Gulf and this oil washes up on the beach as tar balls. In fact there huge amount of oil coming from nat seepage but lots gets eaten by microbes. Wind, solar, concentrated solar power aren't really going to make a dent in power usage especially in cold climates and at higher latitudes where there are about 8 hrs sunlight. Icing of the blades of wind turbines is a problem in really cold climates. The main draw back of these power surces is that these are unreliable (i.e., producing or not producing power) and unpredicatable (i.e., the amount of power produced is quite variable). The most important draw back is that for every megawatt of power from these sources there must be availble the same amount of power from convential sources. When it is -40 deg C in really cold climates, you must have stable and reliable power for furnance fans and electric heaters. Many farms in cold climate have beck up generators in case of power failure. At -30 to-40 deg C you will freeze to death quite quickly unless you can get heat PDQ. Go over to WUWT and read the article about how the Spanish gov shafted all the people who invested their life savings and mortaged the properties for wind farms. A lot of them are face with bankruptcy.
  20. Eric (skeptic) at 03:55 AM on 29 October 2010
    What should we do about climate change?
    h pierce brings a good point about culture (diamonds). First of all, asking Americans to change their culture is not going to work. Non-Americans on this forum who aren't familiar with American culture may not realize this. Imagine a country road with driveways every 200-300 meters or more. Properties will be 20 to 40,000 square meters or more. The driveway is another several hundred meters and leads to a house in the open (no shade trees or winter protection partly due to wildfire concerns, partly for the view). The property may contain some hunting area or a range, a tree harvesting area, or a rough road down to the river. I could write a book, not just a paragraph, about the benefits of such a lifestyle. Changing the equation might include the cost of convenience offset by self sufficiency. For example, do the property owners desire 100% constant and reliable electric power or is they willing to put up with somewhat intermittent power at a lower cost? Are they willing to pay less for a limited range heavy vehicle registration (e.g. haul from home supply store)? Would they be willing to save on commuting costs but still have a reliable and comfortable service (e.g. privately-run luxury van) using express lanes or similar incentives? What I propose is in addition to many good alt energy production suggestions above along with alt energy basic research.
  21. What should we do about climate change?
    H pierce: "The transportation sector will always use hydrocabon fuels" What do you think people will do in 50 years after the full affects of peak oil? The AGW problem will just make us adjust sooner to the shortage of fossil fuels. I noticed a great many bases for wind generators the last time I flew over Texas. In the US wind is supposed to be more cost effective than solar. Spain got 40% of their energy from wind one month last spring. Does anyone have informed comments about wind energy?
  22. What should we do about climate change?
    Ann #92: " – as far as I know – they have never actually replaced fossil fuel based plants. " I think Denmark have replaced some old fossil burning plants already, they do have a lot of wind power, and they are definitely aiming towards closing them all. The following is a rough Google translation of (part of) an article recently found on the Swedish TV website, svt.se: "By essentially a proliferation of wind power, Denmark shall be completely free of fossil fuels by 2050. After two years of work, the Government's Climate Commission presented its ambitious proposal, which is claimed to be surprisingly cheap (costing one half percent of GDP in 2050, scientists believe). Each year between 2015 and 2025, one offshore wind farm that generates 200 megawatts each, is erected. Wind power as a share of energy production should be increased from (now) 20 percent, to 60-80 percent in 2050. When there is no wind energy will be met by biomass and waste incineration."
  23. gallopingcamel at 02:05 AM on 29 October 2010
    What should we do about climate change?
    Marcus (#51) and Argus (#84), Yes, those are real numbers and they surely cast doubt on the viability of future nuclear power projects in the USA . However, the prospects look much brighter in some other countries including China where NPPs are being built for $1.5/We. In France they already built their fleet of NPPs, so they enjoy raking in huge sums by exporting electricity to Germany, Italy, the UK and Denmark. Apparently the French have a base cost of less than $0.05/kVAh. http://bravenewclimate.com/2010/10/25/2060-nuclear-scenarios-p4/ Finally, I pay Florida Power & Light about $0.12/kVAh for my electric power. That company has a wide variety of generating technologies but their lowest cost sources right now are their two NPPs. This is based on inside information that I hope to be able to share on this blog when (if?) I get permission.
  24. Berényi Péter at 01:38 AM on 29 October 2010
    The 2nd law of thermodynamics and the greenhouse effect
    #107 Philippe Chantreau at 07:40 AM on 28 October, 2010 BP, I'm curious. Is it your personal opinion that the atmospheric greenhouse effect has been falsified indeed, as G&T or Kramm seem to argue? No, it is not falsified and at the present level of discussion never will be (as it belongs to the "not even wrong" category). Therefore the very title of that infamous paper is misleading. Gerlich and Tscheuschner in their reply to Halpern at al. say: "In other words, we analyze the rationale and the inner contradiction of derivations of the atmospheric greenhouse effects communicated in the standard climate literature from the viewpoint of a physicist. In part, we are arguing within the context of the standard assumptions put forward by mainstream global climatologists. Nowhere we offer our own model, and we never will." And it is exactly that's what they do. Current formulations of the atmospheric greenhouse effect fail to meet standards of theoretical physics. It is as simple as that. The correct response of course is not to debunk the messenger, but to understand the message and having completed that task to present such a clear definition of the concept, that makes sense even for theoretical physicists. This job is not done so far. Of course I would never deny atmospheric emissivity in thermal IR has a role in maintaining quasi-adiabatic thermal structure in the troposphere. Without it (in a pure N2 - Ar atmosphere for example) vertical thermal profile would be much closer to an isothermal model. It may even be interesting to analyze the effect of adding some more IR emitter to an already saturated narrow emission band, but analyzing its effect on what? Let's consider the problem of average temperatures. It is often stated with no atmospheric greenhouse effect "equilibrium temperature" would be 255 K (-18°C). In fact it is the approximate effective temperature of Earth as it is. However, as you can see, geographic distribution of outgoing thermal IR radiation at TOA (Top of Atmosphere) is very uneven. Effective temperature of an object is defined as the actual temperature of an isothermal perfect black body with the same surface area and same radiative power output. For the Earth this temperature does not depend on its IR emissivity, neither on the IR emissivity of any atmospheric ingredient. It is perfectly determined by ASR (Absorbed Shortwave Radiation), that is, short wave (visible & near IR) albedo and incoming solar radiation flux. Outgoing longwave radiation is not only uneven, but neither it is thermalized perfectly, because at such low temperatures no material approximates a black body and due to the semitransparent nature of atmosphere radiation escaping to space originates in different layers with vastly different temperatures. Therefore it is a tricky business to assign (radiative) temperature to each and every point of the globe. Nevertheless it can be done. If it's useful or not, is another matter entirely. If the surface of the globe is divided up into a grid, having measured the distribution of OLR (Outgoing Logwave Radiation), effective temperature can be calculated for each gridcell, then one can take the (area weighted) average of these temperatures. As <T>4 ≤ <T4>, the finer the grid the smaller this average will be. A decreasing series bounded from below is convergent, therefore with a fine enough grid we can calculate a well defined unique average temperature for the globe as it is seen from the outside. This temperature is much smaller than the oft quoted -18°C, it is certainly somewhere below -30°C. In defining the atmospheric greenhouse effect it also has the advantage of having a chance to be the correct choice to compare average surface temperature against, because comparing average temperatures to an effective temperature hardly makes sense in the first place (like apples to oranges). Is the atmospheric greenhouse effect more than 45°C then (instead of 33°C)? One also wonders what is the correct choice for surface? I know we live at the bottom of the atmosphere, so the special surface separating it from the rest of the globe is important for us. However, at least from the 16th century on we are moving away from an anthropocentric viewpoint, not by pure chance, but it has turned out the Universe is not centered around mankind after all, at least not in any trivial sense. So the correct question to ask is "Which surface is the important one for the climate system?" The question put this way has a unique straightforward answer: the upper surface of crust. The interface between the atmosphere and ocean is a busy one, both material and heat flows are several orders of magnitude higher there than those between the crust and atmosphere/hydrosphere combined. The whole AGW issue is started by the realization of a small, but in a geological sense still fast flow of the element carbon from crust to atmosphere effected by industry. It can be considered a "forcing" precisely because this interface is usually much more "closed" than the one between air and ocean. So when talking about "average surface temperature" we'd better compute it along a true boundary surface of the climate system, that is, along the surface of land and bottom of ocean. This average would be less than 7°C and much more stable than the usual one. In this case is the atmospheric greenhouse effect 25°C? or 37°C? I have no idea if average temperature of the globe as it is seen from space is increasing, decreasing or just fluctuating around some value. Neither do I know if among the several possible definitions of atmospheric greenhouse effect which one has a trend and in what direction. But it would certainly be interesting to know. Average temperature is probably not as important as some say. Entropy fluxes could be calculated in a similar, although slightly more complicated manner (one would need spectral resolution as well) and that would be way more informative than average temperature at an arbitrary interface.
  25. What should we do about climate change?
    MC "...free in Nature.." means not in incombined form such as most metals and most elements. The most abundant materials free in Nature are water, the gases in the atmosphere. This includes small amount of gold, silver and coppper. There are about 10-15 trillion barrels of unconvential oil which are heavy and extra heavy crude oils, tar sand and oil shale. Coal which can be converted to liquid hydrocabons is not included in this catatgory. During WW II Germany obtained most of its fuel from coal using the Fischer-Tropsch proccess as does South Africa. Google "SASOL"' Shell R&D has several pilot projects in north western Colorado in the oil shale basin that uses in situ resistive heating to produces liquid hydrocarbons from kerogene, a waxy material in the shale. Obtaining hydrocabons from oil shale is well-known. During WW II the US Navy has a pilot plant in the Green River basin. They found that heating a ton of average oil shale would yield 25-30 gallons of liquid hydrocarbons and about 10,000 cubic feet of methane and ammonia. "Nope again. The oil companies I worked for are skeptical of climate change because it threatens their bottom line." No way. The transportation sector will always use hydrocabon fuels. If I were the CEO of a big oil company, I would tell the goverment "no carbon taxes and regulations of emisions or I will shut this company down, dismantle the refinery and move it and HQ to a tax haven." If workers can go on strikes so can compsnies. Presently, I pay a carbon tax of Can $0.9935 per Gj of natural gas which costs Can $4.976 per Gj in British columbia. That a tax rate 19.96% The general sales tax on junk food and beer is 12%. No sales tax on good food. Note: Fossil fuels are use for producing distilled spirits. Are you willing to pay a lot more for whisky, vodka, etc. You want to pay a carbon tax on propane for the barbie? In BC there free passes on the carbon tax for low income wage earners who receive a carbon tax credit, for companies exploring for nat gas, oil and minerals, cement producers and smelters making aluminium, lead and zinc. In the domestic economy the cosummer will eventually pay all carbon taxes. I have already noticed that the cost food in the supermarket has risen across the board since trucks bring it to the store. If a goverment can regulate ghg emission and impose carbon taxes, it can not only seize control of the means of production but every aspect of your life. Would you like the lady premier running your life? I don't think so!
  26. Climate sensitivity is low
    Berényi - Further reading into non-equilibrium thermodynamics is proving interesting; in particular the internal fluctuations of such a system. You are correct, the climate is a non-equilibrium system, due to the energy flows. So: You hypothesize that maximal entropy production will prevent positive feedback to greenhouse gases, minimizing climate sensitivity. First objection to your hypothesis: I would hold that the climate has stable stationary states, where there is a local max of entropy. Given the internal fluctuations (including seasons, PDO, ice ages) over the history of the climate, I would find it difficult to believe that the climate could find nearby local entropy maxima to switch to based on small linear forcings; surely the climate would have long since hit those maxima based simply on climate variability. not impossible, but highly unlikely. There may indeed be critical points (ice age initiations, major clathrate/permafrost upheavals); those are points of concern, but certainly not involved in response to small linear forcing changes. Second objection: Climate sensitivity has been measured, and shown to have positive feedback. Your claim that the MEP effect would cause "no positive feedback" (your words) is thereby falsified. Until you recognize this (and you've spent quite some time ignoring this issue raised repeatedly both by me and also by 'e'), the conversation will go nowhere, and I will continue to consider this a lengthy thought experiment unrelated to the real world.
  27. What should we do about climate change?
    quokka #50 Very interesting graph, thanks. Eyeballing it, I'd say it's as variable as weather. Local wind farms are indeed very variable. What I said is that this variability is climatologically predictable in the long term and meteorologically predictable in the short term, allowing you to manage the various sources. And if you have a extensive grid, say covering all Australia, you could smooth out most of the variance. Ok, I don't know much about Australian winds, but that's what I conclude from this study, about an extensive grid over Europe and northern Africa, that could smooth out even seasonal variability. They mention energy costs within the range of 3~4.5 Euro cents per kWh. High wind power penetration by the systematic use of smoothing effects within huge catchment areas shown in a European example Anyway, of course you cannot rely only on wind energy. You will need the occasional backup. But it can be an important part of the final mix, significantly lowering emissions.
  28. The 2nd law of thermodynamics and the greenhouse effect
    The line "greenhouse effect contradicts the 2nd law of thermodynamics" is indeed not from G&T. The quote this is based upon, from the introduction of their paper, is: "The atmospheric greenhouse e ffect, an idea that many authors trace back to the traditional works of Fourier (1824), Tyndall (1861), and Arrhenius (1896), and which is still supported in global climatology, essentially describes a fictitious mechanism, in which a planetary atmosphere acts as a heat pump driven by an environment that is radiatively interacting with but radiatively equilibrated to the atmospheric system. According to the second law of thermodynamics such a planetary machine can never exist. While much shorter, I think the abbreviated line accurately conveys the meaning of G&T's quoted words, although the shorthand line skips major portions of G&T's strawman argument. Berényi - do you indeed feel that the greenhouse effect does not exist?
  29. What should we do about climate change?
    #90: "these fuels have high energy density and are readily prepared from abundant crude oil, which exists free in Nature, " False on two counts; crude oil is not abundant any longer and its most definitely NOT free. Perhaps the illusion of 'cheap oil' came from generations of allowing consumers and producers to get a free pass on cleaning up their own waste products: ie, pollutants including CO2. #91: "The reason big oil and many mining companies are quite skeptical of cilmate change is because they have not experiend any at their field site." Nope again. The oil companies I worked for are skeptical of climate change because it threatens their bottom line.
  30. Human CO2 is a tiny % of CO2 emissions
    #71: "For there are other sources, too, such as outgassing from warming oceans and variable (unknown) outputs from various sources, such as wetlands." There's little or no empirical evidence that ocean outgassing makes a measurable contribution to atmospheric CO2 increase. Compare the monthly MLO record to landlocked stations along the same latitudes -- all the way around the globe -- and you see no differences. But 'unknown outputs'? No doubt those will be hard for you to document. "Land use change wasn't mentioned." And a good thing too, as land use change is now removing terrestrial carbon sinks. As far as increasing rates of change in atmospheric CO2, all the graphs of the annual data I've seen are concave up. That means the slope is increasing.
  31. What should we do about climate change?
    I will also post an on-topic comment :-) As much as I think we need to invest in renewable energy to replace fossil fuel based energy, I think this in itself is not going to stop climate change. It is even dangerous to put too much trust in the whole renewable energy story. The problem is that all renewable energy plants are just installed in addition to the existing power plants, until now – as far as I know – they have never actually replaced fossil fuel based plants. All measures that are taken to fight climate change should deal directly with the problem. Encouraging renewable energy, reducing ecological footprint are indirect methods at the best. It is like trying to stop a leak not at the source, but way downstream. The real issue is the extra carbon we bring into the carbon cycle by burning fossil fuels, carbon that otherwise would stay buried deep down in the earth’s crust. The carbon is exchanged between the atmosphere, the oceans, plants, rocks etc, and temporary shifts may take place (f.i. through deforestration or reforestation), but what matters in the long run is the total amount of carbon that is circulating in the system. None of the current initiatives to stop global warming prevent the further addition of carbon to the carbon cycle. If we continue like this, eventually all carbon that is now stored as fossil fuels will become part of the carbon cycle. It may take a bit longer (if we decrease our energy consumption and use more renewable energy) or shorter, but this will the end result. So, for me the viable options are: - encourage energy companies somehow to keep the remaining fossil fuels in the ground. I am really phantasizing now, cause I don’t see that happening. I think we have to calculate with the assumption that every last drop of petroleum and every last lump of coal will eventually be burnt. - carbon capture and sequestration : harvest the energy of fossil fuels, but keep the carbon behind and store it back in the ground. - mechanical trees: actively remove CO2 from the atmosphere, and sequester the CO2. - reforestation is a short-term solution, as in the long run forests emit just as much CO2 as they absorb. But short-term it can be part of the solution and buy us more time. Regarding geo-engineering: these are short term and emergency solutions at best. I wouldn’t like to live in a world that is only able to survive because we are constantly controlling and readjusting the climate.
  32. What should we do about climate change?
    The reason big oil and many mining companies are quite skeptical of cilmate change is because they have not experiend any at their field site. Many of comapnies have had operation in the field for over a century. Moreover, they don't want the boys in Brussels taking over and running their companies.
  33. What should we do about climate change?
    RE: Fossil Fuel Are Forever! Harold the Chemist says: Boats, planes, freight trains and trucks, military and emergency vehicles, heavy machinery used agriculture, construction, forestry and mining, cars and light trucks, recreational vehicles, and so forth will always require and use hydrocarbon fuels because these fuels have high energy density and are readily prepared from abundant crude oil, which exists free in Nature, by fractional distillation and blending of the distillate fraction, low energy processes which do not involve the breaking of chemical bonds. Even catalytic cracking of the heavy ditillate fractions into lighter fractions for fuel formulation is a relative low energy process. In the heavy industries, only fossil fuels can supply the heat energy and high process temperatures either directy or indirectly (e.g. the electric furnace) required by lime and cement kilns, smelters, steel mills, foundries and metal casting planets, all facilities manufacturing ceramic materials (glass, bricks, tiles, porcelin ware, etc), refineries and chemical plants and so forth. Diesel-electrical generating systems are used extensively throughout the world for primary and back-up power and for power generation in many delveloping countries and at remote locations (e.g., diamond and gold mines, resort islands, drilling rigs, movie sets, etc). Electrical generators using gasoline are quite portable and are used for small snd modest power requriments. Many processes in food production require large amounts of heat for baking, cooking and steam for sterilization, etc which can provided economically by fossil fuels. Drying of grain for storage requires enormous amounts of heat which can only be provided economically by fossils fuels. Energy for space heating especially in cold climates and hot water production and for electricity generation, in particular for refrigeration, communication systems, hospitals and emergency services, is provided most reliably and economically by use of fossil fuels. FYI: A Boeing 747 takes off with 346,000 US gallons of fuel for a long intl. fight. At large airports big jet are more numerous that house sparrows. The largeset cruise ship ever built, the Oasis of the Ocean can carry about 6,000 passengers and 5,000 crew members. These large cruise ships cary enormous amounts of fuel. The most wasteful use of energy is diamond mining. Tons of ore are sometimes processed to obtain a few carats of rough diamonds. About 80% of gold production goes to the jewerly industry. Who among you wants to tell the ladies, "No more diamonds, gold, sliver, platinium, rubies, emeralds, etc for jewerly because we must save the planet from over heating." They would become outraged, ponce on you, take off the Pradas and pound you into hamburger which they would feed with glee to the dingo dogs! I don't want read any more foolish comments about getting rid of fossil fuels. Ain't ever going to happen.
  34. What should we do about climate change?
    daisym "But nobody will tell us how much of a temperature reduction to expect from government’s solutions. Why is this so? Why are scientists silent on this?" Why? Because the very, very unpleasant truth is that we've really mucked it up for this and the next couple of generations. We can reduce our emissions instantly - meaning over the next 20 years. We can set some clever energetic people onto the task of sequestering carbon from the atmosphere (not from using geological carbon fuels) but actually extracting some of the surplus CO2 'pulse' we've injected into our oceans and atmosphere. But in the end, temperature is set to keep on rising for quite a while even with instantaneous cessation. The reason people don't talk about it? Because making that sort of thing the general topic of conversation can lead to despair and hopelessness. People need to feel that they can do some good. We need the occasional blast from the likes of "Storms of my Grandchildren" James Hansen. Mostly we need to keep plugging away at politicians on renewable power, urban design, public transport and all the rest of it.
  35. What should we do about climate change?
    Regarding the safety of nuclear energy: I recently saw a television program about the French nuclear power plants. Title of the program: “Nothing to report”. Ever since nuclear power plants in France have been privatised, the operators cut corners wherever they can to save costs. Regarding the risk of nuclear pollution, instead of the “zero risk” policy from earlier days, they have adopted a “calculated risk” policy. The replacement of parts that are past their usable lifetime is delayed. Instead of a fixed staff, temporary workmen are hired from subcontractors, people who don’t have the necessary skills and don’t have a clue about the risks they are running. If anything goes wrong, the subcontractors take the blame. Nuclear inspectors are put under pressure to put “nothing to report” in their reports, even if they find flaws in the installation. What was most striking for me: this isn’t propaganda from the anti-nuclear lobby. These words and criticism came from people who have worked for many years in the nuclear industry, who used to be proud of their work, and have seen the situation deteriorate, and the risk of disasters increase. And this is France, for Gods sake. A highly developed and technologically advanced country . It makes you wonder what happens with nuclear power plants in developing countries like India, where environmental rules are not that strict, where public health is less protected, where low cost is even more a driver for all decisions. For me, fighting global warming with nuclear energy is like choosing between pest and cholera.
  36. What should we do about climate change?
    Argus (No 84 ) said "To the moderator: What happened to the principle of keeping comments relevant to the current thread, and deleting any off topic comments? About 90% of this thread is a detailed discussion about the pros and cons of nuclear power and its economy. Hardly relevant to the title "What should we do about climate change?" " I think you have missed the intent of the pro nuclear commentators. All are very passionate about climate change and are actively researching the best way to reduce CO2 emissions without destroying our very high standard of living. The only example of a large developed country reducing carbon emissions without compromising living standards is France. In just 20 years France constructed 58 nuclear power stations replacing almost all its fossil fuel generation. Today France has low carbon emissions (per capita) compared to all other G20 countries, a strong economy, exports 4B euros of non carbon energy energy annually to Britain, Germany and Italy, has a social welfare and health system that is the envy of Europe and their citizens retire at 60. If all G20 countries had followed France's lead 30 years ago climate change would not be the issue it is today. Thus the debate about the pros and cons of nuclear power is very relevant to what we should do about climate change.
  37. What should we do about climate change?
    #81 adelady With respect to geothermal, nobody doubts that there is a huge amount of heat in granite rock a few Ks below the surface. Engineered Geothermal is a great story - huge reserves, potentially baseload power, small environmental footprint. The problem is that no electricity generation on a commercial scale has even been demonstrated and at best is several years away. Geodynamics was said to be the company closest with it's facility in the Cooper Basin in SA, but they have had their share of problems, are well behind schedule and still are to make a decision on a proposed 25 MW commercial scale demonstration plant. They have had federal govt. financial assistance. It's worth following developments, but far too early to make a judgment as to whether EGS is going to be any more than at best a bit player. I hope it is, but at this stage it would be folly to bet the future on it. It's worth keeping an eye on Geodynamics
  38. What should we do about climate change?
    I'm a bit behind... but in response to #9 (waste + terrorists). It might not take much nuclear waste to make a bomb, but the issue is the technology. For the 400+ power stations in the world and the plethora of terrorists, none have succeeded (or even tried?) yet. And what if they did fly a plane into a nuke power station? My point is that such scenarios are still a better option than global warming - unless there is a viable energy alternative. That debate is above. For waste, digging numerous great holes in geologically stable Australian outback, suitable encasement, etc would do the trick nicely. We don't seem to have worried about the typical 4 tonnes p.a. of U238 each coal-fired power station emits from their chimney stacks! As for #14 - curbing population growth. Removing benefits to 3rd-plus-more child would be a start (as I gather Germany does). A taxi driver I had the other day was onto his 8th child and wanted more because his father had had 12! In this country Canberra will happily pay benefits for those children, education, health, housing benefits, etc. (Am I allowed to say he was from Africa?) Anyway, I'm not sure if I have the answer, but at least it should be raised as a serious issue in politics and solutions explored.
  39. Skeptical Science Firefox Add-on: Send and receive climate info while you browse
    I have the same experience as fredb. I use Firefox 3.6.11 on Windows XP. Are there blocking calls in the code...? Seems like a very cool thing!
  40. What should we do about climate change?
    Peter Lang (#58): "What is the basis for implying that the nuclear figures are over-optimistic" --- Just take alook at Marcus (#51)! Those are the real costs. Your figures are pure fantasy. The poor Finnish people will have to pay forever for the scandalous new Olkiluoto 3. Building the plants is one thing. Then we have to take care of the radioactive waste 'forever'. That is going to cost as much as building the plants, but that will be our grandchildren's worry, not ours, right? To the moderator: What happened to the principle of keeping comments relevant to the current thread, and deleting any off topic comments? About 90% of this thread is a detailed discussion about the pros and cons of nuclear power and its economy. Hardly relevant to the title "What should we do about climate change?"
    Moderator Response: The current topic does include the possibility of nuclear power as an option. All comments are still moderated for compliance to the comments policy. If you wish a more in-depth discussion of, say, solar power or geothermal or tidal, please kick start the flow of discussion with a comment in that direction. That way we all can benefit.
  41. What should we do about climate change?
    Nuclear costs much more than it should and could cost in the Western democracies. This is mainly because ofd the regulatory impediments we have built up over the past 40+ years. Some examples of the sort of impediments and regulatory distortions to the market that are blocking nuclear in Australia are: 1. nuclear power is prohibited 2. high investor risk premium because of the politics 3. Renewable Energy Targets 4. Renewable Energy Certificates 5. Feed in Tariffs for renewables 6. Subsidies and tax advantages for renewable energy 7. Subsidies and tax advantages for fossil fuel electricity generators 8. subsidies for transmission and grid enhancements to support renewable energy 9. massive funding for research into renewable energy 10. massive subsidies for research into carbon capture and storage(CCS) 11. Guarantees that the government will carry the risk for any leakage from CCS 12. No equivalent guarantee for management of 'once-used-nuclear-fuel' 13. Massive subsidies and government facilitation for the gas industry, coal seam gas and coal to gas industries (despite the latter putting toxic chemicals into the ground water and the Great Artesian Basin water) 14. Fast tracking of the approvals process for wind power, solar power, gas industry, coal industry while nuclear industry remains prohibited from even fair comparative studies by Treasury, Productivity Commission, ABARE, Department of Climate change and more. We can just imagine what the approvals process would be like for a nuclear power plant!!
  42. Human CO2 is a tiny % of CO2 emissions
    Ned - Richard is a NZ skeptic. You can imagine the conversations. Lately to accuse NIWA of fraud about NZ warming. Richard, without a reference to contradict the established carbon accounting, what is your point here? Ned provides the evidence for acceleration by the way though I think that pretty irrelevant - 1960s rates are scary enough.
  43. Human CO2 is a tiny % of CO2 emissions
    Richard Treadgold at 16:05 PM, regarding land change use, in particular deforestation which has been ongoing for centuries. From 1100 to 1500 significant deforestation took place in Western Europe, global deforestation accelerating from the mid 1800's with the result that only about half of the Earth's original mature tropical forests remain. It is also clear how seasonal plant growth causes significant variation in CO2 levels globally, with dramatic annual variations regionally. The question that needs to be answered, is, is that CO2 that would have been sequestered by the now missing forests being considered as a forcing, and has it been adequately accounted for given that considerable deforestation took place before 1750, particularly in the northern hemisphere, 1750 being the base from which the effects of anthropogenic CO2 are referred back to.
  44. It's the sun
    OK, so your graphs show basically nothing. They either cover too short of time so that a supposed correlation or lack there of is most likely a figment of one's imagination... OR ... they lack a 'key' as is the case with the graph labeled "reconstructed temperatures" which makes it a bunch of squiggly lines... one marked 2004 one marked medieval warming. If the lines represent different ways of measuring the temperature of the past? why the difference? Shouldn't we be focusing on data that has been reliably taken... not theoretically? Can't we agree that regardless of how steep the upward trend of some graph is that our actions are not helping?
  45. gallopingcamel at 17:12 PM on 28 October 2010
    What should we do about climate change?
    lin (#79), That is a really good question. Today's nuclear power plants consume about 0.7% of the Uranium in the fuel. While this is pretty inefficient it still makes sense in a world where Uranium costs $106 per kilogram and even after processing, reactor grade Uranium costs only $2,500 per kilogram (cf. Gold at $42,000/kg). Thanks to Jimmy Carter, NPPs in the USA use a "Once Through" fuel cycle so 99.3% of the fuel ends up as high level nuclear waste. Even so, the cost of the fuel is a tiny part of the cost of generating nuclear power. According to the EIA, NPP fuel averaged $0.00529/kVAh in the USA (2008): http://www.eia.doe.gov/cneaf/electricity/epa/epat8p2.html Even with a "Once Through" fuel cycle, proven reserves of Uranium and Thorium will last thousands of years. Fortunately, 4th generation fission reactors are capable of burning over 99% of the fuel which means that we can expect the Uranium and Thorium reserves to last at least 100,000 years. To get a feel for the issues involved in a rapid expansion of NPP generating capacity, you should spend some time on "Brave New Climate". This is a web site run by Barry Brook who is a "general all around egg-head" (I mean that in the nicest possible way). This link should get you started: http://bravenewclimate.com/2010/10/14/2060-nuclear-scenarios-p3/
  46. Skeptical Science Firefox Add-on: Send and receive climate info while you browse
    I think this is great ... but have a problem. After installing (Firefox 3.6.12 in Ubuntu 10.10), my firefox tab freeze for extended period and it all becomes unusable. Disabling the add-on, all works fine again. :(
  47. What should we do about climate change?
    I like this as a summary. Got to page 7-8 and check out the estimates on geothermal and solar. Compare to the estimates in the upper section of p7. http://www.abare.gov.au/publications_html/energy/energy_10/ch_1.pdf
  48. What should we do about climate change?
    #79 lin How long will the uranium last? Try here: are uranium resources sufficient? The answer is, at the very least more than long enough until the next generation of reactors with advanced fuel cycles dramatically reduce the need for mined uranium. A recent MIT study came to the same conclusion. As for thorium, there is substantially more thorium than uranium available.
  49. Richard Treadgold at 16:05 PM on 28 October 2010
    Human CO2 is a tiny % of CO2 emissions
    scaddenp, The assertion was straightforward, as I quoted it:
    the additional CO2 is being produced by burning fossil fuels
    Land use change wasn't mentioned. No, I can't supply a reference for what you ask. But I didn't mention it either. You forgot my question: What is the evidence for an acceleration in the rising atmospheric level of CO2? When you say "temperature-induced rises in CO2 are feedbacks, not forcings", does that mean they don't form part of the increased amount in the atmosphere? But of course they do, and they are not anthropogenic, so they ought to be deducted from the anthro emissions budget. That's all I meant. Cheers.
  50. Human CO2 is a tiny % of CO2 emissions
    Richard Treadgold writes: It's incorrect to assert that the whole increase comes from fossil fuel use. For there are other sources, too, such as outgassing from warming oceans Richard, there are two problems with this. First of all, the oceans are a net sink of CO2. That is, the net flux of CO2 is from the atmosphere to the ocean, not the reverse. See lots of papers on the subject, including Takahashi 2009 and Sabine 2004. Secondly, we know the total fossil fuel flux to the atmosphere quite well, and it's clearly larger than the annual increase in atmospheric CO2. In other words, fossil fuels account for more than 100% of the atmospheric increase (with the excess being taken up by oceans and the biosphere). Richard also writes: It's also incorrect to assert that the increase in atmospheric concentration is accelerating. The Mauna Loa record shows no sign of that. In fact, graphing the yearly change (the data given at the Mauna Loa site) shows that since about 1998, the rate of increase has actually slowed. So would you cite your source for the acceleration, please? From the Mauna Loa data, the linear trend in CO2 for each of the past decades is as follows: 1960-1969: +0.8 ppmv/year 1970-1979: +1.2 1980-1989: +1.6 1990-1999: +1.6 2000-2009: +2.0 That is a very clear acceleration. It's a bit disturbing that someone acting as "Convenor, Climate Conversation Group" would be so seriously mistaken on multiple basic facts about CO2 in the Earth system. What kind of "climate conversations" are you having, and who are you having them with? Somehow, you seem to have picked up a lot of misinformation.

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