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JMurphy at 20:30 PM on 27 October 2010What should we do about climate change?
transjasmine, just your first paragraph has many fallacies - if only you had read more on this site. Anyway, here are the threads you need to read to help with your misunderstandings : Does Breathing Contribute to CO2 Build-up in the Atmosphere ? Global Warming 'Positives' CO2 - Everyone's Favourite Pollutant ClimateGate Like I say, that is just from your first paragraph - there is a lot more but I don't have time at the moment to point you in the right directions. Maybe later...unless someone else can be bothered to waste their time on this ! Basically, perhaps you had better start here : Newcomers Start Here -
Esop at 20:03 PM on 27 October 2010It's cooling
The deniers jumped on the same cooling train back in 2008 and predicted that we were going to enter a Maunder Miniumum due to the combination of the lowest solar minimum in more than 100 years and a negative PDO. With 2010 smashing all sorts of records, the deniers were proven dead wrong, but they are getting away with it. The MSM is all over tiny dicrepancies in the predictions of the real scientists, but dead quiet on the massive failure of the skeptic cooling predictions from 2008. Those predictions were all over the blogs and deniers even went on television proclaiming rapid cooling. Henrik Svensmark is one of the most high profile ones. Last month was the warmest (by far) in the UAH record, despite maximum cooling effect from the lowest solar slump in more than a century, despite the cooling effect from the much heralded (by deniers) negative PDO, and despite the onset of the second strongest La Nina on record. Nature is turning all the natural drivers to Max Cool and September was still the warmest by far. Food for thought. 2011 will flatten out and perhaps cool slightly, due to the strong La Nina, so the deniers will make their usual noise and the MSM will bite, hook, line and sinker and make first page material out of pretty much every single bit of denier disinformation. 2012 temperatures will come back with a vengeance, however, as we will likely enter an El Nino, and the solar cycle will have gained some momentum, in addition to the always present and increasing warming from the increasing concentrations of greenhouse gases. -
Peter Lang at 20:01 PM on 27 October 2010What should we do about climate change?
Bern@16, I cannot give your reply the detailed answer it needs here. You might be interested in the “Zero Carbon Australia – Stationary Energy Plan- Critique”. http://bravenewclimate.com/2010/08/12/zca2020-critique/ This provides cost estimates for solar thermal and wind power, with biomass and hydro backup, to meet our projected demand for electricity. The cost is around $500/MWh ($270 to $1,200/MWh), but these costs are based on highly optimistic assumptions. The power supply would be unreliable. -
h pierce at 19:51 PM on 27 October 2010Measuring CO2 levels from the volcano at Mauna Loa
ATTN: All FYI After analysis, the concentration for CO2 in a sample of local air is reported for purified dry air (PDA) which does not occur in the earth’s atmosphere and is comprised of nitrogen, oxygen, the inert gases, which are the fixed gases, and CO2. The composition of PDA (i.e., the relative amounts of the fixed gases and CO2) is fairly uniform through out the atmosphere and is independent of location, elevation, pressure, temperature, humidity, biological and human activities except for minor local variations in particular with respect to CO2. This is the origin of the term “well-mixed atmospheric gases.” For PDA at STP (i.e., 273.15 K and 1 atm. pressure), there are presently about 390 ml, 17.4 millimoles, 766 mg, or 0.000766 kg of CO2 in 1 cubic meter. The density of PDA at STP is 1.29 kg per cubic meter. The concentration of CO2 in PDA is 390 ppmv. In real air there is no uniform distributon of the masses of the consituents including water vapor and clouds in the atmosphere in space and time as is shown by daily weather maps of the various regions of the earth. High pressure cells have more mass of the gases than do low pressure cells, and thus there is no uniform distribution of CO2 in the atmosphere. Air containing water vapor is less dense than dry air and has less mass of the fixed gases and of CO2 both of which will vary with humidity. Mountains are a prominent geological feature of the continents and the density of the air in them is less than at sea level and diminishes rapidly with elevation. Real air is the term for local air at the intake ports of an air separation plant and usually contains aersols, reactive gases, volatile organic compounds, water vapor, fog, rain, snow, CO2, nitrogen oxygen and the inert gases which are the fixed gases and comprise about 99% of PDA. The metric used for CO2 in climate model calculations is ppmv and is incorrect since the concentration of CO2 is only valid for PDA. The metric that should be used is either mass per unit volume or moles per unit volume. This is flaw in climate model calculations since the mass of the air is complex function of the variable mentioned above. The mass of CO2 per unit volume in local air will usually be less for elevation upto ca 30,000 ft. (i.e., the height of the tallest mountains) than that calculated for PDA. Climate models that use concentation of CO2 for PDA will give results that are to slighty too high. Moist tropical air (e.g.,90 deg F and 100% humidity) can contain 20% less CO2 than PDA. For much useful into on the properties air go to Universal Industrial Gases Inc.'s website at http://www.uigi.com/air.html By Harold, the chemist. -
MarkR at 19:50 PM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Re: Albatross #11 The 6 C I gave was for 2 doublings of CO2, as our current emissions pathway is along the IPCC SRES A1. Warming by 2100 seems almost certain to be less than this, but even the 3-4 C we may see by then is an absolutely massive change. It's not just warmer nights and evenings, but climate zones moving hundreds of miles north and hundreds of millions of people needing to protection against rising seas. -
perseus at 18:45 PM on 27 October 2010What should we do about climate change?
I'm afraid relying on conservation, nuclear or renewables is merely tinkering at the edges, and it could be like cutting off a few of the the Hydra's heads! Jeavons paradox reminds us that efficiency savings may not be as great as expected. Moreover whilst some renewables work well up to a percentage of power, further increases lead to grid instability and expensive storage is necessary. Nuclear is limited unless we move to thorium. However bear in mind that most of our carbon emissions are non grid based and widely diversified. Although I generally support most 'green' initiatives, we really have focus on reducing the key drivers. Economic, and population growth, the latter being a delayed effect. Consumption is a social illness which our politicians and media encourage us to participate in so we need political change. With regards to technologies as unpopular as these are I suggest the following should be our focus Carbon capture and storage Reforestation in the tropics and possibly beyond depending on albedo effects 'Reversible geoengineering' such as increased cloud cover (yes this could be an oxymoron) but only in conjunction with genuine carbon reduction initiatives. 'Industrial geoengineering', by focusing on carbon reductions in transport emissions rather than on industry which according to NASA has a net cooling effect Increased research into technologies such as algae based Biofuels and artificial carbon capture from the atmosphere should be encouraged. -
John Brookes at 18:21 PM on 27 October 2010What should we do about climate change?
Bern@16 - "Why design systems to deliver 100% all night?" Well, not all night maybe, but on those really hot nights in Perth, there is no doubt that everyone will keep their air conditioners going, at least until the early hours of the morning! -
Bern at 17:54 PM on 27 October 2010What should we do about climate change?
@Peter Lang, I'd have to disagree with your comment that solar thermal with storage can "only provide a few hours of full power generation when the sun is not shining" - the output post-sunset depends on the amount of storage you have. If your demand curve *needs* full output after sunset, then you need to make larger storage tanks and increase the size of your collectors, that's all. But given most (all?) demand curves show a significant decrease post-sunset, why design the system to deliver 100% all night? I agree with you, though, that the cost is an issue - the price per MWh delivered is important. But I'm also interested - was the cost for solar thermal based on the limited scale projects that have been deployed in the past, or on projected costs of large-scale baseload generators? I'm sure the early nuclear systems cost a bit more than they do now, given the 60-odd years of (highly subsidised) development that's gone into them. The bigger problem with nuclear, at least in Australia, though, is political. 60-odd years of scaremongering about the dangers of nuclear waste will be hard to overcome... -
Peter Lang at 17:43 PM on 27 October 2010What should we do about climate change?
Further to Barry Brook's comment, the $165/MWh cost for solar energy is not comparable with the cost of energy from nuclear. Nuclear provides power on demand, whereas solar provides power when the sun is up and the sky is relatively clear. They do not provide much power in winter. Even solar thermal power stations that have some storage (such as molten salt storage) can only provide a few hours of full power generation when the sun is not shining. There is no such thing as a solar baseload power station and probaly never will be (other than with huge subsidies). I agree with the statement: "Most importantly, we must stop listening to disinformation." -
transjasmine at 17:31 PM on 27 October 2010What should we do about climate change?
john chapman, its interesting to me that you would suggest curbing the population growth, how exactly would one do that? i have an opinion on this issue relating to global climate change but i'll let you answer before i rant. -
Barry Brook at 17:13 PM on 27 October 2010What should we do about climate change?
Marcus, I'm sorry, I have to dispute this on a number of grounds. First, you're quoting a few cherry-picked assumed costs, not real-world costs. Second, you're not considering LCOE. I have an article in press in the journal Energy (the DOI is 10.1016/j.energy.2010.10.039 but it's not online yet), and based on a meta-review of the last 10 years of authoritative energy literature (encompassing the IEA, EIA, MIT, IPCC, RAE, NREL, NEEDS etc), normalised to 2009 USD, we found the median LCOE for nuclear was $54/MWh (n=8), and for solar thermal it was $165/MWh (n=4). Your statement is not supported. -
transjasmine at 17:09 PM on 27 October 2010What should we do about climate change?
hmm now what could we do to fix this huge problem? how about some kind of tax, we'll call it a tax on carbon, something that everyone has to pay because we all breathe, don't take into account that plants and tree's need Co2 to survive, its poison a dreadful poison. ignore climate gate the scientists were joking about falsifying data. oh just ignore the ice cores showing co2 following temperature, the ice cores were joking as well, just to confuse you haha do you get it? ignore ice core and sea core data showing just 500,000 years ago a temperature 5 degree's higher than today which heated at a faster rate 15 degrees per century. ignore the urban heat island effect and the iris effect. ignore the fact that a small period known as the Holocene climatic optimum was warmer than it is today. so what can we do about global warming? absolutely nothing, its a natural occurrence you may as well try and stop the sun from burning. -
Marcus at 16:29 PM on 27 October 2010What should we do about climate change?
Also, Bern, you can find more info on Concentrated Solar Power here: http://en.wikipedia.org/wiki/Concentrated_solar_power -
Marcus at 16:28 PM on 27 October 2010What should we do about climate change?
The closest I can get, Bern, is this: http://www.reuters.com/article/idUSTRE58867I20090911?pageNumber=1. I hope that helps. Also, I've heard of capital costs for coal power stations of between $1.80 & $2.20 per watt. Its also worth noting that the Coal Industry enjoys many tax breaks-especially in Australia. Water costs, waste disposal costs, land rehabilitation costs, diesel fuel costs-*all* are, in part or full, covered by tax payers! -
Glenn Tamblyn at 16:25 PM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
The projections for warming due to a CO2 doubling - 3 Deg, 6 Deg etc need to be considered in the context of time scale. Most estimates of temp change that fall into that 3 Deg band are based on the Charney Sensitivity - how much the climate will change to a doubling considering only shorter term factos, typically on time scales up to a few decades at most. The full temperature response to a forcing may take centuries to manifest as it involves other feedbacks on longer time scales - Ice Sheet changes, altered vegetation patterns and ocean currents. These are the ones suggesting figures up towards 6. One area that often seems to get under-represented when we consider the impacts of any temperature change is the impacts on food production. Our domestic crops co-evolved with us during the Holocene and are often quite tied to temperature regimes. The argument is sometimes put that it has been warmer in the past. Yes it has but we weren't trying to feed 9-10 Billion people at the time. A few DegC change means that every ecosystem on the planet will experience an adaptation pressure due to temperature and precipitation changes. Ecosystems can adapt, but they need time to do so. The pace of these changes, perhaps more than therir absolute magnitude is a huge ecosystem stressor. The risk is that they cannot adapt fast enough. And the technical term for many of these ecosystems is 'farm paddock'. The big risk from AGW, because it compounds with all the other environmental pressures, is the threat to food supply, and the flow on social chaos that may follow. And just a few degrees can cause that in a world that is already close to not being able feed everyone. -
Marcus at 16:23 PM on 27 October 2010What should we do about climate change?
John Chapman, there is nothing fanciful about concerns regarding the waste & terrorist implications of nuclear energy. The US has enormous problems dealing with the accumulated nuclear waste of the past 60 years, & it doesn't take much nuclear waste to build a dirty bomb. Not to mention the danger posed by the facilities themselves were someone to fly a plane into it! -
Bern at 16:22 PM on 27 October 2010What should we do about climate change?
Marcus, you don't happen to have a link to that info, do you? I'm curious if they discussed costs for any other electricity sources. I saw some numbers that suggested a modern coal-fired power station would cost only $1.50 or so per watt up-front, but would cost another $0.50 per watt per year in fuel costs (can't remember where I saw that, unfortunately). -
Marcus at 16:10 PM on 27 October 2010What should we do about climate change?
Well Barry, according to a talk given by G Poornima & L Isensee, the cost of installing a Concentrated Solar Power (as of 2009) comes out to between $2.50 to $4.00 per watt. By contrast, most nuclear power stations cost around $5.00 to $6.00 per watt to build-then have fuel & waste disposal costs on top of that! Its worth noting that the high cost of nuclear power comes even after *60 years* of development & many hundreds of billions of dollars in subsidies for the industry! -
Tom Dayton at 15:50 PM on 27 October 2010Waste heat vs greenhouse warming
Yes, RSVP, GHGs of course do slow the escape of waste heat. But GHGs do that equally as they slow the escape of heat from all other sources, including the Earth's heat resulting from incoming solar radiation. That's why the orders of magnitude lower quantities of waste heat make it inconsequential to worry about. That's also why GHG increase is consequential to worry about: GHGs slow the escape of heat from all sources. -
RSVP at 15:48 PM on 27 October 2010Waste heat vs greenhouse warming
#348 CBDunkerson (resending after cleaning up, and adding just a little more) The follow, http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law ...starts by saying... "The Stefan–Boltzmann law, also known as Stefan's law, states that the total energy radiated per unit surface area of a black body per unit time" note the words, "per unit surface area", and "per time" You are right in thinking along the lines "what goes up, must come down", but for some reason you are ignoring the idea that the time it takes to "go up, and down" could vary (depending on conditions). As I was saying about the heat sink on the back of an audio amp. They dont make them bigger for nothing. The more surface area, the faster the heat can radiate, so as to not allow the amp to overheat (for instance). Likewise to our earlier analogy, the viscosity of water is a real force that impedes flow. So in the same way they have to actually spend more money for larger pipes to get large amount of water to where it needs to go in a timely manner. http://en.wikipedia.org/wiki/Viscosity And more to the point, if the heat flow outward is being restricted by GHGs (and that is a big IF), it could only be helping the accumuation of waste heat. AND as the surface area of the Earth is finite, this will limit the amount of energy released per unit time. If you wait long enough. If there was a break in waste heat emmision, the Earth would have a chance to get rid of it, but we never stop emitting this heat. -
RSVP at 15:40 PM on 27 October 2010Waste heat vs greenhouse warming
#348 CBDunkerson The follow, http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law ...starts saying... "The Stefan–Boltzmann law, also known as Stefan's law, states that the total energy radiated per unit surface area of a black body per unit time" note the words, "per unit", "per time" You are right in saying thinking alone the lines "what goes up, must come down", but for some reason you are ignoring the idea that time it takes to "go up, and down" could vary. As I was saying about the heat sink on the back of an audio amp. They dont make them bigger for nothing. The more area, the faster the heat can radiate, so as to not allow the amp to overheat (for instance). Likewise to our earlier analogy, the viscosity of water is a real force that impedes flow. So in the same way they have to actually spend more money for larger pipes to get large amount of water to where it needs to go in a timely manner. http://en.wikipedia.org/wiki/Viscosity And more to the point, if the heat flow outward is being restricted by GHGs (and that is a big IF), it could only be helping the accumuation of waste heat. -
scaddenp at 15:12 PM on 27 October 2010What should we do about climate change?
"97% of climate scientists". If this is based on Doran, then the 97% is even tighter than that - climate scientists actively publishing on climate change. While this might be simplification for radio, I think it is overstating a case which I believe is poor practise. Leave that to denialists. If you overstate something, then it is easy for someone to discount your entire argument on basis of that error. On the other hand, if the argument is understated, then close examiners looking to refute your argument will find things worse than they thought - and perhaps pause to reflect.Response: If I'm crunched for space, I usually say "climate experts" and if someone asks "what's a climate expert?", I say a climate scientist who is actively publishing peer-reviewed papers on climate science. -
Barry Brook at 14:46 PM on 27 October 2010What should we do about climate change?
I'm curious to understand the justification and evidence for this statement: "... like solar-thermal generators that are now providing energy in Europe more cheaply than Nuclear generators" -
adelady at 13:49 PM on 27 October 2010What should we do about climate change?
John 97% of scientists? Should that be 97% of climate scientists or involved scientists or something. Or is that going to muck up your word count.Response: I'm just guessing here but I'd bet Kevin went with the simplification of "scientists" instead of "climate scientists" for the purpose of talking to a general radio audience. -
adelady at 13:48 PM on 27 October 2010What should we do about climate change?
John. Population? The real problem is consumption and associated waste (by humans). Was it here I read that ants have a couple of hundred times the biomass of the human population? They seem not to have run out of their resources. Probably because they reuse and recycle every single element required for life. Anyway, human population numbers will decline so long as the focus remains on educating girls and women. China's approach was probably the best they could do given the extreme problems they faced. But it was a disaster, and continues so, because of the failure to educate the population at large. The men and women who were born around the time the policy was introduced have been educated and acculturated to preference for male children and to desire 4 generations under one roof. http://www.thisis50.com/profiles/blogs/24-million-chinese-men-wont?xg_source=activity A system that encourages and supports later marriage and esp. later birth of a first child firstly reduces the generational overlap thereby reducing total population even with an unchanged birthrate. A policy and a program was necessary. This particular policy will continue to cause problems for a very long time. -
Joe Blog at 13:25 PM on 27 October 2010The 2nd law of thermodynamics and the greenhouse effect
KR The second law is about entropy, heat flows from hot to cold is just sticking this in the most simple terms. If you state the second law as chaos increases, you are mostly just going to get blank stares back, but its not a bad approximation of the second law. But entropy increases or stays the same, is the second law... now if you modify the system however? -
Joe Blog at 13:14 PM on 27 October 2010What should we do about climate change?
In australia solar may be viable, but this is not true for every corner of the globe... There is nothing wrong with the fourth and fifth generation thorium salt fast breeder reactors. There is as much disinformation floating around about this technology as anything. And this does offer a viable alternative to fossil fuels anywhere. Thorium is cheap, they are vastly more efficient than heavy or light water reactors. And produce a fraction of the waste... If the world was serious about cutting its reliance on fossil fuels, this should be the first avenue of investment. -
John Chapman at 13:11 PM on 27 October 2010What should we do about climate change?
Using less energy can, at best, offset the increases in population and energy demands. While solar has a role, especially in WA, the global solution for energy has to be nuclear. Any concerns about waste or terrorism (fanciful) are insignificant compared to the consequences of global warming. The other action is to curb population growth. China, to their credit, at least has aggressive nuclear energy plans and is doing something about population. One of the benefits of not having a democracy - one can make unpopular decisions! -
The 2nd law of thermodynamics and the greenhouse effect
Albatross - I agree. Berényi - MEP discussions probably belong on How sensitive is our climate, not here. The 2nd law of thermodynamics is quite secure, and the nonsense of Gerlich and Tscheuschner well disproven. MEP is off-topic here.Moderator Response: Agreed. Take it to that other thread, please. -
Kooiti Masuda at 12:53 PM on 27 October 2010The 2nd law of thermodynamics and the greenhouse effect
The message of the main text of this thread is that such assertion that "greenhouse effect contradicts the 2nd law of thermodynamics", as Gerlich and Tscheuschner made in their paper published in 2009, is false. I think that there is no objection to this message among the commenters here. The story of the principle of maximum entropy production (MEP) is related to the general title "The 2nd law of thermodynamics and the greenhouse effect", but MEP is something distinct from the 2nd law, and is much less estabilished. I think that it is an interesting subject of academic science to discuss whether it holds in the real world. But I think that formulations of the model systems that should represent the real world is different among scientists (e.g. between Berényi Péter and Ozawa et al.), and that the answer to the preliminary question "maximum among what?" is different accordingly. So MEP does not seem to me helpful as a piece of policy-relevant science of climate at present. -
scaddenp at 12:43 PM on 27 October 2010It's cooling
Adrian- well I expect that next La Nina will start the chorus "start of cooling trend" again - until the next El nino. Not a constructive way to look at it perhaps? Wouldnt it be better to look that the temperature and compare with temperatures the last time the world have a similar magnitude of El Nino/ La Nina? With a TOA energy imbalance, you need iron-clad wishful thinking to propose that we are going to get cooler. On the other hand, if you are prepared abandon your denialism if its warmer in 5 years, then that would be progress. -
Craig Allen at 12:40 PM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Oops, sorry for assisting Adrian to take the tread off-topic. The page that JMurphy links to is the most effective response. -
Craig Allen at 12:34 PM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Adrian Smits #4 And according to UHA January 2010 was the hottest January in the 32 year satellite record, August was the second hottest month, and 2010 was the second hottest year, and we have just seen the hotest decade, yada yada yada. But rather than cherry picking hot or cold periods within the dataset how about we consider the trend over the entire record. It is clearly positive and recent data in no way contradicts that long-term trend.Moderator Response: Please respond on the appropriate thread. See comments by readers and moderators above. -
Albatross at 12:29 PM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Mike @9, Good point. It is rather unfortunate that so much emphasis is placed on 2100 and doubling CO2. Hopefully the IPCC will rectify that in AR5. I'm not sure that +6 warming for doubling CO2 is the most likely scenario-- +3 C seems the most likely. That said, the IPCC might need to entertain other scenarios which allow for the fact that CO2 levels (or equivalent) will likely treble over pre-industrial levels circa 2100. -
JMurphy at 12:14 PM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
I have replied to adrian smits on the Is Global Warming Still Happening ? thread.Moderator Response: Thank you! -
JMurphy at 12:12 PM on 27 October 2010It's cooling
adrian smits wrote (on the Isn't global warming just 2 °C and isn't that really small? thread) : "According to UHA satellite data the last week hasn't been this cold in many years for this old rock and I expect before this la Nina ends its gonna get a lot colder yet! Lets just wait 4 maybe 5 more years and see where we are at before doing anything rash.After 14 years of nearly flat temperatures that's 1996 to now. Three or four years of actual cooling should put a stake in the heart of the AGW agenda." Firstly, could you provide the link to that amazingly devastating data ? (Well, you seem to think it is) Secondly, last month was higher than the same month of the previous year, as was every other month - and, generally, some of the highest ever recorded. Where is the cooling you believe in ? Thirdly, are you agreeing that if there are 4 or 5 more years of warming, you will finally admit that your so-called skepticism has been wrong ? Fourthly, you have already been shown to be wrong about your belief in cooling over the last 14 years, but perhaps you have some hidden evidence you would like to show ? If so, please prove that your belief has some substance. Lastly, what do you believe this hidden agenda is ? Some sort of conspiracy ? -
Yvan Dutil at 11:41 AM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Adrian Smits, No obvious increase for a entended even if this was a real phenomenon, whould by no mean confirm than the heating is no longer ongoing. In non linear system, increase are done in step. See http://www.pnas.org/content/105/38/14308.fullModerator Response: The other, relevant, thread, please. -
Albatross at 11:18 AM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Adrian Smits, Your post is off-topic. Anyhow, lower tropospheric temperatures inferred from AMSU data are still running above average (with respect to the mean calculated over the satellite record). Regardless, short-term variability/noise is a distraction from the long-term warming trend. And yes, temperatures have been rising since 1996. See Hansen's latest paper. Ironic that in response a post where the author is talking about temperature changes over many thousands of years and you choose to post about the change in global temperatures in the last couple of weeks. Anyhow, until a couple of weeks ago the UAH data for the mid troposphere were at record highs. The very recent decrease in positive global temperature anomalies of late is because the atmosphere is finally responding to the strong La Nina event. And there is no "agenda" here, just science, please take your rhetoric and spin and agenda somewhere else.Moderator Response: The other, relevant, thread, please. -
archiesteel at 11:17 AM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Sorry for the off-topic reply, I hadn't seen John's response to adrian's comment. -
archiesteel at 11:16 AM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
@adrian: "According to UHA satellite data the last week hasn't been this cold in many years" Are you *really* going to gauge future climate from *one week* of data? "After 14 years of nearly flat temperatures that's 1996 to now." Hardly. Using the same UAH (not UHA) data:"Three or four years of actual cooling should put a stake in the heart of the AGW agenda." Considering we've had about 40 years of warming, we should have expected the spectre of climate change denialism to never again rear its ugly head, but I guess there's no rest for the wicked...
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The 2nd law of thermodynamics and the greenhouse effect
BP, ok sorry I misunderstood the water vapor point somewhat. RE the convention of moving along the landscape vs. changes to the landscape: it seems to me that distinguishing these concepts is somewhat important to your hypothesis is it not? MEP states that the system will tend towards the maximum path of entropy production given the constraints. As I understand it, it says nothing about whether a change in constraints can raise or lower the entropy production of the system. If positive feedbacks are thought of as changes in the constraints of the system (as the net consequence of the initial forcing), then there is no reason to predict that entropy production must increase (or stay the same) as a result of these changes. In this way, positive feedbacks can reduce entropy production with no contradiction to MEP. In short, how do you determine whether positive feedbacks are changes to the path of entropy production or changes to the constraints of the system? -
adrian smits at 11:03 AM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
According to UHA satellite data the last week hasn't been this cold in many years for this old rock and I expect before this la Nina ends its gonna get a lot colder yet! Lets just wait 4 maybe 5 more years and see where we are at before doing anything rash.After 14 years of nearly flat temperatures that's 1996 to now. Three or four years of actual cooling should put a stake in the heart of the AGW agenda.Response: Your assertion of "14 years of nearly flat temperatures" is discussed in "Phil Jones says no global warming since 1995" as well as "It's cooling" or even "It hasn't warmed since 1998". Please take that discussion to a relevant thread. -
Albatross at 10:29 AM on 27 October 2010The 2nd law of thermodynamics and the greenhouse effect
KR @93, I have been following this debate with interest from the side lines. I think your last sentence sums everything up nicely-- a very elaborate red herring at that. So this "debate" all seems an effort by BP to distract form the subject at hand. Or does BP agree with G&T's misunderstanding that the so-called "greenhouse effect" somehow contradicts the second law of thermodynamics? There is really nothing to debate concerning the validity of G&T's work, b/c the science on that is settled-- G&T have been shown to be wrong. If BP is trying to argue that the climate system has some alleged significant negative feed backs, surely that debate belongs on a more appropriate thread, and not here. -
scaddenp at 10:26 AM on 27 October 2010Blaming global warming on the oceans - a basic rebuttal
Joe, I have no doubt about the importance of ocean in climate mechanisms (why else include oceans in climate model) but I do not think you can attribute climate change on current scale to UNFORCED change in ocean circulation. As to higher glacial max T with lower CO2, I would point out that glacial cycle is very slow with time for equilibrium. Climate is currently out of equilibrium with forcing. (note TOA energy imbalance). Given ocean mixing rates, I find it hard to see how ocean can equilibrate to current CO2 forcing in much less than 1000 years. -
The 2nd law of thermodynamics and the greenhouse effect
Berényi - Once again you are proposing a complex hypothesis of negative feedback that will defeat global warming: "This rearrangement would counteract GHG effect on entropy production rate (like a negative feedback)". And once again this is contradicted by the actual data. Such a MEP effect would already be in effect now, and in the past, and would be part of measured climate sensitivities. There is no such negative feedback observed in the data. And if your hypothesis is contradicted by the data, it's time for a new hypothesis. This entire MEP side excursion is a red herring. -
Joe Blog at 09:46 AM on 27 October 2010Blaming global warming on the oceans - a basic rebuttal
scaddenp at 07:54 "since oceans cant generate heat, then heat from oceans cant be forcing only a mechanism." This is simply not true,the rate of evaporation/water vapor, is dependent on the ocean surface T, the ocean surface T is a product of solar heating/back radiation/ back radiation is a product o atmospheric T, which is a product of ocean T/energy export in to the atmosphere, and the thermal characteristics of the atmosphere... the real variable being water vapor/or surface of the oceans T. So if you change the energy distribution around the globe, by moving energy from below the surface in the tropics to the surface at higher latitudes, you can force a change... By raising the average surface T, you raise the average evaporation/and the average GHE, and the back radiation will increase in line with atmospheric T's... you are going to have a hard time explaining past interglacial max T's without taking this into account... CO2 levels were lower, but T's were higher... You are assuming that its a linear relationship between surface T's and oceanic T profiles. -
MarkR at 09:46 AM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Joe Blog, I will clarify this later. What I meant was that 2 C global warming from today's level would put us beyond what appear to have been the warmest temperatures of the past 600,000 years. Which is one reason why we're not sure about feedbacks beyond that point! -
Berényi Péter at 09:45 AM on 27 October 2010The 2nd law of thermodynamics and the greenhouse effect
#90 e at 08:30 AM on 27 October, 2010 You're basically saying that an increase in water vapor is a decrease in entropy, so this feedback is impossible given MEP. No, I would never claim such a thing. Water vapor is free to do whatever it is inclined to. I just say given MEP some rearrangement of the climate state is likely in response to increased IR opacity in order to approach maximum entropy production rate under the new circumstances. This rearrangement would counteract GHG effect on entropy production rate (like a negative feedback). Water vapor redistribution is just a possibility. Average opacity of the atmosphere can decrease happily in weak H2O IR absorption bands even with increasing average moisture, provided its distribution gets a bit more uneven (higher moments are increased). It can happen on all scales, including sub-grid ones relative to computational climate models. how do you distinguish between a movement along the potential entropy production landscape, and a wholesale change to that landscape? It is a matter of convention to some extent. What you usually consider a forcing is supposed to rearrange the landscape while so called feedbacks only push the climate state around in the phase space. Is it simply a matter of external forcings vs. internal? If so, is not the ocean "external" with respect to the atmosphere? I don't think there are internal forcings, I would rather call changes not forced by external agents unforced ones. As the climate system is close to a critical state (see SOC - Self-Organized Criticality) one would expect the correlation length go up implying large spontaneous (unforced) fluctuations on all scales. And no, the ocean is in no way external to the climate system. In fact most of the climate happens in the oceans, there's thousands of times more mass in them than in the atmosphere. -
Albatross at 09:06 AM on 27 October 2010Isn't global warming just 2 °C and isn't that really small?
Hi MarkR, In the above figure looks similar to what Lindzen showed in his debate against Dessler to try and convince people that there is no reason for alarm ;) Joe Blog, "show most o the past interglacials warmer than this one" Well, maybe not by 2100....we are probably going to be experiencing a super interglacial. According to Petit et al. (1999) previous inter-glacials were about +2 to +3 warmer than at the time of the most recent stratum in the core (circa 1950 if I remember correctly). We are probably in for at least another +2 C warming. Now, what were sea levels during those previous inter-glacials? -
Berényi Péter at 08:48 AM on 27 October 2010The 2nd law of thermodynamics and the greenhouse effect
#88 Riccardo at 08:14 AM on 27 October, 2010 What do you mean by "everything else held constant"? I mean what is ordinarily called a no feedback situation. That is, cloudiness, snow cover, atmospheric water vapor distribution, winds, ocean currents, vegetation, etc. are not allowed to change in response to increased IR optical depth. I say in this specific case entropy production rate gets smaller than it was before optical depth was increased. And the entropy production rate of what, in first place? The global entropy production rate in W/K, measured as difference between entropy of outgoing longvawe vs. incoming shortwave radiation. Can't you increase entropy production rate by increasing surface temperature? No, I can't. Not as if I have not tried, but all simplified radiative or radiative-convective models I have checked so far have this vexing property. As surface temperatures are increased, entropy production rate declines. I conjecture a general principle is at work in the background. The MEP usually also implies minimum entropy contents of the system and higher temperatures mean higher entropy. But I do not have a formal proof (yet). Anyway, if you could show us an understandable climate model that goes against this conjecture, that would be informative. I've never heard anyone claiming the impossibility of positive feedback based on MEP principle You are welcome :)
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