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Comments 91651 to 91700:

91651. alan_marshall at 12:01 PM on 23 March 2011
       The Libertarian Climate Conundrum
       RSVP @ 47 Human beings are the only species with the capacity to destroy the Earth. We are also the only species with the capacity to save it, but only if we act as one. As a species, we therefore have a duty of stewardship. Dr Tim Flannery, author of “The Weather Makers”, is well known to those who follow climate science. In his latest book "Here on Earth", he has a vision of what is needed: The immediate challenge is fundamental - to manage our atmospheric and oceanic global commons - and the unavoidable cost of success in this is that nations must cede real authority, as they do whenever they agree to act in common to secure the welfare of all. This does not mean the creation of a world government, simply the enforcement of common rules, for the common good. Even if the current disorganised national efforts succeed in stabilising the concentration of CO2, it will not be enough. If we are to ever reduce atmospheric CO2 to a safe level, we need to extract the bulk of what has been emitted from 1750 up till now. That will require either carbon sequestration on an industrial scale, or geo-engineering. Both these solutions will involve decisions we make as a species, not as competing peoples. As Archbishop Desmond Tutu warned at Copenhagen, nations will "sink or swim together". That does not imply draconian control of our everyday lives. I am a believer in markets. For example, rather than ration gasoline, it is much better to price it in a way that gives people an incentive to use less, while providing compensation so that their overall standard of living is not reduced. Some of my thoughts on economic and political solutions are published at www.climatechangeanswers.org.
91652. JulianRGP at 11:55 AM on 23 March 2011
       Preventing Misinformation
       I found the article really useful, so this comment is about just one point in the article The article describes the statement "CO2 is less than a mere four 100ths of 1% [of the atmosphere]" as an error (one of the "three principle errors" - "principal" by the way). The problem with Thompson's statement is not that it's erroneous (it's equivalent to saying 400ppm if my arithmetic is correct), but that it's being misleadingly used to support an erroneous case. The error is in the inference and the remaining two statements. I am happy with the following paragraph in this article - a small quantity can have a big effect - which shows why the statement in question is being misleadingly used. I think that simply saying it's an error leaves the article open to valid criticism. Of course the word "mere" in Thompson's statement is pejorative, but could be turned around to advantage. Although the quantity of CO2 is a "mere four 100ths of 1%" of the atmosphere, we already know that a mere three 100ths of 1% is enough to stop the earth turning into a snowball.
91653. scaddenp at 11:46 AM on 23 March 2011
       Zero Carbon Australia: We can do it
       If cooling is impaired, then that limits output. No contradiction here. Efficiency losses on ramp-down arent that great. They do work much more efficiently at constant load agreed, but then you do need base-load. 80% for CCGT?? 60% is outstanding. Got a link for someone claiming 80%? I also dont believe a single cycle turbine has ever hit 60%. However, for all that defense, I think moving away from coal power is highly desirable. They are inefficient, coal is dirty industry, and we cant afford the climate cost. That is reason enough. No need to gild the argument with spurious other factors.
91654. Don Gisselbeck at 11:37 AM on 23 March 2011
       CO2 has been higher in the past
       In what way does "technology will save us" (what "we are adaptable" means) differ from "God will save us"? Both are entirely faith based and neither has a shred of evidence to support it.
91655. Marcus at 11:33 AM on 23 March 2011
       Zero Carbon Australia: We can do it
       scaddenp. During Summer, peak demand for power frequently increases, & this leads to load shedding-this is usually reported in the press as an inability for the base-load power stations to ramp up supply. "You get efficiency losses (effectively useful heat that isnt being converted) as station comes off load, but they can certainly come down (and up) fast." Yes, but the key point is the efficiency losses-this does limit its flexibility. Most renewable energy power stations can adjust their output *without* those same efficiency losses. Of course, coal power stations aren't very efficient to begin with-with only 35% of the heat from the coal being used to create steam. Personally, I think gas (be it natural gas or methane from decomposition of organic material) is much better-as even a conventional Gas Turbine gets 60% thermal efficiency-with a Combined Cycle Gas Turbine getting as much as 80%.
91656. adelady at 11:24 AM on 23 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       Gilles@84. Huh? Perhaps you and I have a different definition of 'develop'. Why on earth would a poor country "develop =only= through an increase of FF consumption."? They now have options, much more developed options than we had at the same stage of development out of mainly rural communities. One of those options is to choose, really choose, to 'develop' at a rate that can be supported by renewables only. It might be slower than you or I might prefer, but it is still development. If they get it right, as their building standards upgrade, they'll be able to use solar roofing materials pre-coated, ready to plug in to business and domestic power supplies. Distributed power generation is a far better option for currently developing countries anyway for a whole heap of reasons. If the pace is slow and steady, when the accumulating wealth of the population allows a real move to individual cars for a larger middle class - there'll be a ready supply of EVs to meet that need too - and those people will be in a position to upgrade their re-charging facilities as well if they need to. There is nothing exciting or glamorous about the 19th century technology of digging stuff up to burn it to generate power. I can see no good reason why anyone would want it, apart from politicians addicted to ribbon-cutting events. Even then, I presume local mayors and the like could cook up some sort of ceremonial ritual when a few villages gather enough resources to establish a communal windfarm, if they wanted to.
91657. scaddenp at 11:18 AM on 23 March 2011
       Zero Carbon Australia: We can do it
       Well, it feels very strange going into bat for Ken, but... "Also, if Coal Power stations are *so* flexible, then why do we get constant load shedding in Summer?" I'm not entirely sure what you mean, but station efficiency and generation capacity is dependent also their ability to reject heat to cool steam. This most certainly has a seasonal influence. " Why do the plants operate at close to 100% capacity 24/7, when off-peak demand is barely *half* of that during the day? They'd hardly waste the fuel, so I'd guess its because they *can't* turn down the power to match supply." I think you need to have some pretty complete figures on demand and production. Stations most certainly CAN turn down the power to match demand. You get efficiency losses (effectively useful heat that isnt being converted) as station comes off load, but they can certainly come down (and up) fast. I'm not that familiar with overall Australian generation system, but I would expect hydro to be used when possible, BIG coal to provide base load, and "others" to balance demand. Do I know anything about coal power stations? Well I am programme leader for this project and I've looked at a live data from quite a few Australian power stations.
91658. dana1981 at 11:08 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       HR -

       "Surely the point of the article is that you have some how accounted for the warming in this period. Is that the point?"

       This post is a rebuttal to the "skeptic" myth that the pre-1940 warming was purely natural, and as large as the current warming, thus the current warming could also be natural. The article refuted all three of these points. 1) A significant portion (close to half) of the pre-1940 warming was anthropogenic. 2) The pre-1940 warming was smaller than the current warming. 3) We know the current warming is anthropogenic based on physics. Even if the first two "skeptic" points were true, it does not follow that the current warming is natural.
91659. Marcus at 11:07 AM on 23 March 2011
       The True Cost of Coal Power
       "All the rest is totally unable to power a modern country, despite everything you can read." Yep, that's exactly what I'd expect you to say....don't believe the *facts*, says Gilles, only believe my unsubstantiated assertions. I've shown that many 1st World Countries are now producing *more* wealth with lower energy input than what they were 30 years ago (just read the IEA reports if you don't believe me), & that many of those same 1st World Countries are now sourcing more of that energy from renewable sources than 30 years ago-so that really does put the kibosh on your claims. As renewable energy technology continues to improve in price, reliability & total output, the more we'll be able to generate wealth *without* the need for fossil fuels-or nuclear power. Seriously, Gilles, I'm totally *done* with you on this matter. You clearly want to keep living in this fantasy land where nothing but fossil fuels can generate wealth-even when the facts don't support you-so I really don't see why I should continue wasting my breath!
91660. Marcus at 11:00 AM on 23 March 2011
       Zero Carbon Australia: We can do it
       "It seems that I am 'horribly' wrong all over the park Marcus. It only that were true." Yes, you *are* horribly wrong Ken-& still are-but that's what happens when you rely on Coal Industry propaganda & not actual *facts*. Do you deny the press reports about 85% of Queensland's Coal mines being partially or completely flooded? Do you honestly believe that won't have-or hasn't already-had impact on supply? Also, if Coal Power stations are *so* flexible, then why do we get constant load shedding in Summer? Why do the plants operate at close to 100% capacity 24/7, when off-peak demand is barely *half* of that during the day? They'd hardly waste the fuel, so I'd guess its because they *can't* turn down the power to match supply. As to Transmission & Distribution losses, in spite of your claims this has everything to do with *distance*-the longer the distance between energy supply & energy demand, the greater the losses in electricity along the line. Distributed Generation is the only way to reduce-or eliminate-these losses, but inflexible coal power stations don't fit into a distributed generation framework very well. I've read far & wide on Wind-Farms, & your comments continue to display your ignorance regarding them. A 3MW Wind Turbine, operating at 30% Capacity Factor, will actually generate 8,000MW-h per year. Of course, without storage, some of the excess capacity-especially at night-will either go to waste or won't be harvested (i.e., excess capacity will get shut down). This is why VRB's have proven so successful at raising Wind Farm Capacity factors-to as high as 60% to 70%. Again, from my reading, current capacity factors are between 20% to 40%, with most modern Wind-farms achieving 30%-35% (without storage)-your ignorance of these facts doesn't make them any less real. Your talk of the negative health impacts of "Infrasound" merely prove that you spend way too much time reading The Australian for your information-a well known, anti-renewable newspaper. There is absolutely *no* medical basis for this so-called "disease", & its extremely odd that no one who actually has the wind farms *on* their properties (& are thus being *paid* for the use of their land) has actually been effected by Infransound-only those who live several kilometers away & object to the view. I wonder how they'd feel living near a coal power station & its associated, open-pit coal mine? Your claims about the distance taken up by a wind farm are equally facetious. Are you going to tell me that Coal Power stations, & their associated mines, don't take up land? Yet, unlike Coal Power stations, land with wind turbines on them are still able to be used for other purposes. Lastly, though your concern for endangered birds is....touching, its not a very good reason to oppose wind farms. Modern Wind Farms actually have very little negative impact on bird populations &-in fact-its been shown that the negative environmental impacts of the mining & burning of coal do *far* more damage to bird populations (per MW-h of electricity generated) than wind turbines. You know, what with all the land degradation & the harmful emissions from the power station-as well as the looming impacts of climate change. Seriously, Ken, I think you need to read a little more widely than the brochures handed out by WMC, BHP & Rio-Tinto.
91661. johnd at 10:54 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       Robert Way at 13:24 PM, I agree. The links provided in another post --"[DB] There is no robust evidence (AFAIK) showing that oceanic cycles affect the global land+sea temperatures, as Tamino thoroughly shows (here and here for starters)." were not very informative. The Tamino examination of the MEI only looked at 1975 onwards whilst the AMO examination went back to 1880. Firstly they should all address the same time frame, and secondly the matter cannot be properly understood or quantified by individual analysis of separate systems. The objective should be to examine the global response and so the systems from every ocean, every ocean, have to be examined in order for the nett response to be determined. It is very clear that all the systems oscillate differently, at times in concert, at other times offsetting and yet other times intensifying the effects of adjacent systems. The time spent in each phase varies as well as the magnitude, so trying to analyse just one system over less than one complete oscillation provides virtually nothing meaningful in a global sense. Has anyone produced a study that has tracked the nett total heat that is sunk or released to or from the oceans due to all such the cycles?
91662. scaddenp at 10:37 AM on 23 March 2011
       Zero Carbon Australia: We can do it
       Firstly, I dont buy that we need to go to zero. We just have reduce one hell of a lot (but then I work in oil/coal so maybe that is rationalization). Hard to see how we drop coal for steel-making. Second, I was impressed by the range of fuel options for liquid fuels detailed by cudby in from smoke to mirrors for those applications that have to have them. Will they be as cheap as FF. Nope, but then who thinks climate change will be free?
91663. les at 10:34 AM on 23 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       84 Gilled I know what an envelope is mathematically. That proves exactly and identically nothing about your statements except that they are mumbo-jumbo psudo science. You say the words but don't link them to reality. I really have no idea why you bother. It fools no one. For the attention, maybe? Anyway, at least we agree that you have completely failed to backup your points I had noted above. So there, really, is an end to it.
91664. scaddenp at 10:26 AM on 23 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       "Obviously poor countries can develop only through an increase of FF consumption," Here we go again. Tell us what to read to back that assertion.
91665. scaddenp at 10:20 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Damorbel - still havent got a yes/no to #752. Are you prepared to have nature be the arbitrator?
91666. HumanityRules at 10:18 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       Dana, In your 'Other forcing' section you give two references neither of which actually deal with the role of ocean oscillations from what I can see (Meehl and Tett .
91667. HumanityRules at 10:13 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       27 dana1981 I still don't get it. Surely the point of the article is that you have some how accounted for the warming in this period. Is that the point? My objections are that you haven't, there are so many fudge factor and unquantified 'others' that you can make your sum add up to whateve you want. Why choose 66% for the unrealised warming, it could just as well be 33% over a 30 year period? Did you factor in equilibration for solar, I don't see that? You seem unconcerned that solar forcing may be 3X too high compared with recent estimates. You throw in fudge factors such as ocean cycles without stating magnitudes. Solar may be 0.1oC but let's fudge that up to 0.15oC with indirect effect which in other contexts you would probably dismiss as speculative. Does it matter that 0.15+0.15 does not equal the warming for this period (which maybe 0.4oC or 0.45oC)? Anybody can make numbers add up to whatever they choose to when there is so much wiggle factor. Here's my version Warming for 1910-1940 is 0.45oC (HADCRUT) CO2 contribution is 0.07 (33% of .22, equilibration) Solar contribution is 0.03 (1/3 of 1W/M2 based on newer TSI estimates) 'Other' forcing must be what's left 0.35oC Conclusion - Ocean oscillations and 'others' play the major role in climate. I don't necessarily agree with that conclusion but give yourself enough wiggle room and you can make any conclusion you want.
91668. Gilles at 10:06 AM on 23 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       adelady, I don't know what you mean by "have to". Obviously poor countries can develop only through an increase of FF consumption, despite all what is written about all marvelous possibilities to make it without them. They probably don't read enough. Les - I checked that even in English, envelopes are not always packaging letters ;) http://en.wikipedia.org/wiki/Envelope_(mathematics)
91669. pbjamm at 09:34 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel@761 "In this situation radiation through the intervention of GHGs is exchanged with the higher levels of the troposphere which are below freezing. Some of the xchange might well be with deep space, but only a small part; which of course cannot easily be separated out." Would you please expand on this using some science? I can not make sense of what you are trying to explain.
91670. johnkg at 09:21 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       #754. Thanks Phil Glad that everyone's agreed on that one!
91671. damorbel at 09:07 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #760 DSL you wrote:- "Ok, then put it in a clear vacuum box and point it at the night sky. With no internal heat source, and no way to receive energy (according to your physical model), it should cool down at its rate of emission (and internal conduction) until it reaches near absolute zero" There is a comparable effect known as 'clear sky' frost; the condition when surface frost appears e.g. on car windshields, even when the air teperature is not below freezing. In this situation radiation through the intervention of GHGs is exchanged with the higher levels of the troposphere which are below freezing. Some of the xchange might well be with deep space, but only a small part; which of course cannot easily be separated out.
91672. DSL at 08:53 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Ugh, LJ -- not the alleged solar cooker evidence. It is proof of nothing. The reflective surface focuses incoming radiation. That radiation could be coming from the atmosphere. Your argument is that we can't differentiate between radiative transfer and conduction/convective transfer. In other words, why doesn't the solar cooker cool to near absolute zero when pointed at the open night sky? Something must be heating it. (expected response) Ok, then put it in a clear vacuum box and point it at the night sky. With no internal heat source, and no way to receive energy (according to your physical model), it should cool down at its rate of emission (and internal conduction) until it reaches near absolute zero. I'll wager that it won't, though. I'll wager that it cools more slowly, because even if we warmed it up to 50C before we put it in the box it's still receiving infrared radiation from the atmosphere. Photons can't choose their paths.
91673. MarkR at 08:32 AM on 23 March 2011
       Understanding Solar Evolution Pt. 1
       #4 perseus: feel free to check my maths (please?! :P ), I did it by dividing the luminosity by the speed of light, since power/c = force for light. Then turning into pressure by dividing by the area. I assumed the radiation would be absorbed, I suppose it could be reflected and you'd have to multiply it. Iirc, luminosity grows as approximately M^4 but it's a long time since I did astrophysics! In that case some massive stars (50 times solar mass, say) would have significant radiation pressure at some levels.
91674. dana1981 at 08:29 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       

       "at equilibrium, this CO2 change [from 1900 to 1940] would be expected to cause a 0.22°C increase in the average global surface air temperature."

       Due to the ocean lag and other anthropogenic effects, "the best estimate of the anthropogenic contribution to the 1910-1940 warming is approximately 0.1 to 0.15°C". By 1960 it's 0.15 to 0.2°C, or roughly half of the 0.3°C average surface warming. I'd call 50% significant.
91675. les at 08:16 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       mods - I really do think that damorbel, and particularly 755 & 757 violates the comments policy. Although not exactly an ad hominem attack, it is an attack on the work of many, many physicists through the ages. On behalf of those upon who's shoulders most of us stand - bun on who's feet damorbel seems to be stepping, I pray you, make it stop!
91676. L.J. Ryan at 08:09 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       CBDunkerson750 You said: "In that both cause an area to be warmer due to redirected electromagnetic energy it isn't a matter of belief, but rather observed reality." Focusing a large radiative input to a specific point is NOT what proponents argue. Redirecting radiation is not a point of contention. I say cold atmosphere radiation can not shorten terrestrial radiation, GHG proponents say otherwise. Google solar cooker. The principal works by redirecting and focusing, from a large hot area, radiation to a small target area. When facing the sun (hot),the focal area (the small area) gets very hot. When facing away from the sun (the cold atmosphere) the focal area (small area) gets cold. So the small target area looses energy via the large area to the cold atmosphere. See this process (unlike the magic box) abides the 2nd law, Hot to Cold. The atmospheric LW does NOT accumulate within the target area. The target area looses energy to the radiating atmosphere. GHG physics concludes conversely.
91677. damorbel at 08:05 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #756 muoncounter That's exactly what #755 explains. In #750 CBD writes :- "In that both cause an area to be warmer due to redirected electromagnetic energy it isn't a matter of belief, but rather observed reality." No amount of redirecting, refocussing adding together etc.,etc., of photons can increase their energy: warmer the Earth's surface may well be but it is not a radiation effect*. *It is actually a gravity effect.
91678. Rob Honeycutt at 08:03 AM on 23 March 2011
       CO2 has been higher in the past
       Jay Cadbury... (Continued from the Preventing Misinformation thread.) Models tell us very little about whether we can survive if we heat the planet back up to the levels of 65 mya. Models only tell us about the climate. Survival is going to have to do with the ability of species other than ourselves to adapt to such a dramatic and rapid change in climate. Paleoclimate records tell us far more about how species deal with rapid climate change. And there you don't find such pretty pictures of how well living things adapt to change. Yes, we are a very adaptable species. We are probably the most adaptable mammalian species there is, though probably less adaptable than many species of insects. So, is that the world you want to bequeath to your grandchildren and great-grandchildren? Us and the insects? Again, not a pretty picture. But don't worry. There's nothing we can do that nature won't fix in, say, another 20 million years. A mere blink of the eye, as they say.
91679. Chris Colose at 08:02 AM on 23 March 2011
       Understanding Solar Evolution Pt. 1
       perseus, In our sun, gas pressure is much more important, but radiation pressure can become significant in much larger stars.
91680. Gilles at 08:01 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       I'm sorry dana but I don't understand. Figure 1 shows no statistical anthropogenic warming between 1900 and 1940, but you say that a significant percentage of that small warming is anthropogenic ? I can't get your point . Which percentage and why is it "significant" ?
91681. Rob Honeycutt at 07:55 AM on 23 March 2011
       Preventing Misinformation
       Cadbury... I'm moving the conversation over to CO2 was higher in the past where you can read a response to your comment here.
91682. muoncounter at 07:48 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Ryan I have read the entire thread, in case you've missed the numerous references to comments from November and December. You apparently have also missed the point about 'at the same frequency'; IR photons have considerably less energy than visible light photons. CBD's point here is quite valid, with or without the parabolic geometry (which is a mere artifact of your solar cooker analogy). You've not proved anything with it, except how much you are willing to argue for the sake of argument.
91683. damorbel at 07:45 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Just to make one thing clear. Photons from a 'hot' (5780K) source like the Sun can be refocussed at any distance (if the mirror is big enough) to recreate the surface temperature (5780K) of the source, but no higher. No amount of refocussing etc., etc., of photons from a cold (255K) source, like the upper troposphere, can produce a temperature higher than 255K... anywhere. It's the photons you see, they don't have enough energy. They may have all the power (W/m^2) you can imagine* but no amount of refocussing, adding together, accummulating in reflecting cavities etc., etc. will raise their energy. Or, in other words, increase the temperature of.... anything. That is what the 2nd law is all about. It why quantum theory holds sway. And why the 'GH' effect is not a radiation effect... from... GH gases. * Power is not energy. Power is W(atts); energy is J(oules). A surface emitting power has two options it can emit relatively few 'hot' photons to get power 'P'. Or it can emit a large number of low energy photons to get the same power 'P'. There is a lot of grief on this thread cause by contributors not distinguishing between power balance and energy balance by defining both as 'W/m^2', that is a mistake.
91684. BBP at 07:40 AM on 23 March 2011
       Understanding Solar Evolution Pt. 1
       In the interest of keeping a high standard here, I think I need to point out that why a star becomes a red giant is an unsettled question. "Despite all the investigation into the subject, the question has yet to receive an answer that is satisfyingly simple and sufficiently rigourous. There is still no consensus on why stars become red giants." (Stancliffe et. al. http://arxiv.org/PS_cache/arxiv/pdf/0902/0902.0406v1.pdf) I also think that showing ishochrones and/or evolutionary tracks would be more helpful than an HR diagram
91685. RSVP at 07:05 AM on 23 March 2011
       The Libertarian Climate Conundrum
       alan marshall 38 And when we should have this "Climate Protection Agency", I suppose it is up to them to best decide how fast or how slow climate needs to change, since there will always be some target. Or will they take climate back to how it was in 1850?
91686. dana1981 at 07:04 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       I also don't know why you're referencing the 1999 'hockey stick'. I provided a link to more up-to-date reconstructions in Comment #30.
91687. adelady at 07:03 AM on 23 March 2011
       The Libertarian Climate Conundrum
       rsvp @45. Only if it was chlorine. Other methods don't have quite the same impact, though they do have some.
91688. dana1981 at 07:01 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       Gilles, the "hockey stick" shows a ~0.4°C temperature increase from 1900 to 1940, and ~0.3°C increase from 1900 to 1970, just like the instrumental temperature record. As I have said several times, a significant percentage of that small warming is anthropogenic. I hope this is the last time I have to say it.
91689. keithpickering at 07:01 AM on 23 March 2011
       Understanding Solar Evolution Pt. 1
       OK, one reference I found is Guinan & Ribas 2002, ASP Conference series 269, 85, available here. The luminosity function (fig. 2) appears to be an exact match to the 7% per billion years log function (which isn't too much different from Gough's linear function). The equation would be L(t) = L(t₀) [e^{ln(.93)(t-t₀)}] ... where age t is expressed in Gyr.
91690. RSVP at 06:57 AM on 23 March 2011
       The Libertarian Climate Conundrum
       villabolo #37 about that white shirt... Was originally white by dumping used bleach into the environment, which externalizes costs as well, or is this not so?
91691. adelady at 06:54 AM on 23 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       "b) improvement doesn't result in a decreasing energy consumption for a given wealth, but in increasing the wealth for a given energy consumption" But that doesn't have to be from fossil materials, does it? This item about Bangladesh tells us people can just skip right over the fossil powered step. Once they've made a bit more money with the system they've got, they'll be buying a bigger and better version of that. They won't sit down and wait for government or big business to build a centralised fossil burning power station.
91692. Dr. Jay Cadbury, phd. at 06:49 AM on 23 March 2011
       Preventing Misinformation
       Well I will say this website is far more fair and honest than realclimate or ( -snip- ). @Rob It is a possibility that we cannot return to the GAT of 65 mya but I argue that since humans are the most adaptable species ever to exist, and since animals were present 65 mya, we can survive in this type of climate. My problem with your argument is that there just isn't anyway to test it. In my opinion, the only way to test such a hypothesis would be to find a planet similar to earth's, with people on that has a co2 concentration of 560ppm. Of course it is a fool's dream so we have to use models. And I'm not saying that this is bad and models shouldn't be used, only that models are only models.
       Moderator Response: You must comment on the appropriate threads. See my moderator response on your previous comment, for instructions on how to find those. Regarding models, see "Models Are Unreliable." Further off-topic comments will be deleted from this thread.
91693. Phil at 06:46 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       What is disputed...a cold atmosphere warms the warmer earth. No-one believes the cold atmosphere warms the warmer earth. The Greenhouse effect slows the rate at which heat escapes from the earth. Period.
91694. les at 06:45 AM on 23 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       ... I realize that that first sentence looks like I think I've dug my self into a hole. That was poorly put. It was meant to be advice to Gilles... redundant, I know; as he's clearly off digging himself into other holes else where.
91695. e at 06:43 AM on 23 March 2011
       Pre-1940 Warming Causes and Logic
       Gilles, >the shape is perfectly natural and can be produced only by natural variability There is no such thing as a "natural shape". The shape does not tell us whether it is natural or not. That can only be obtained via understanding of the underlying physics and forcings that are involved. That is precisely what the scientific literature does (and what this post discusses).
91696. scaddenp at 06:43 AM on 23 March 2011
       The Climate Show Episode 9: Nuclear power and hot spots
       "It doesn't say much about the origin of ground warming." only if you don't accept conservation of energy. Come on, you agree with one result of radiative physics but disagree with another based on exactly the same physics.
91697. L.J. Ryan at 06:35 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       CBDunkerson750 You said: "In that both cause an area to be warmer due to redirected electromagnetic energy it isn't a matter of belief, but rather observed reality." Focusing a large radiative input to a specific point is NOT what proponents argue. Redirecting radiation is not a point of contention. What is disputed...a cold atmosphere warms the warmer earth. Google solar cooker. The principal works by redirecting radiation, (from a large area) to a small focal area. When facing the sun, the focal area (the small area) gets hot. When facing away from the sun the focal area (small area) gets cold. How can this be? Maybe you should understand what you proclaim to know.
91698. scaddenp at 06:32 AM on 23 March 2011
       The True Cost of Coal Power
       "despite everything you can read." So once again you are making an unsubstantiated assertion and at the same time admitting that this assertion flies in the face of what has been written. Right.
91699. scaddenp at 06:28 AM on 23 March 2011
       Teaching Climate Science
       Gilles - fig 2 is normal science. You create a model for reality, you test it by calculating results and comparing to reality. What method would YOU propose for looking at how much temperature would change based on natural forcing only? Create another identical earth - or use your best computer model for earth? This normal science in every field I am used to.
91700. scaddenp at 06:20 AM on 23 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel - I didnt describe any experiment. I proposed that an experiment be designed such that normal understanding of physics and your understanding would calculate a different result. This is normal way to test scientific arguments. I asked if the experiment didn't go your way, whether you would be prepared to abandon your view and read the textbook. (ie, behave like a scientist). Got a yes/no? In fact, have you got an experiment that you think validates your views over mainstream physics?

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