How much greenhouse effect can we expect from doubling CO2. Chris explains us: http://chriscolose.wordpress.com/20...ve-modelsearths-climate-system-analysis-pt-2/ Actually calculations with MODRAN (demonstrated on request) suggest a dry sensitivity just below one degree but who cares. How important is that positive feedback? Some quotes from the techical summary of 4AR of the IPCC: Furthermore Soden and Held 2006 did some modelling with positive feedback, So the key words are models feedback and models. How about empirically testing things to the actual world? To be continued
Remember how the scientific method works? So if the original hypothesis is that greenhouse effect causes about four degrees temp change per doubling (Arrhenius) and that is tested false, instead we get to about one degree, how do we get back to the higher range to be able to persist in the climate hype? We invent positive feedback. A modification of the original hypothesis. But did anybody "use the hypothesis to predict the existence of other phenomena, or to predict quantitatively the results of new observations"? Sure Soden and Held made all kind of cyber worlds and, lo and behold, the positive feedback thing fit exactly. But that's not valid, testing in an artificial environment, created after the ideas of the programmers, where just the adjustment of a few parameters makes pigs fly. How about testing positive feedback to real world data? But how? In engineering feedback is a general technique where the output of a system is sampled, compared to a desired output, and a corrective input is given which should give a change in output in the opposite direction as the measured distance. The whole theory of feedback is about how to determine the amount and timing of this corrective action. However in our atmospheric feedback processes there is no desired output. the chaotic movements are not controlled. There are only forcings (sun, ocean, etc) that may or may not be affected by feedbacks but always with a certain delay, since these processes take time. This is an essential feature of feedback. The dynamic responses to changes in forcing as these feedbacks act on the rate of change in the process, negative feedback would counter the effect, positive feedback would enhance it but... with delay. Hence (due to the lag) in a positive feedback situation, whenever the forcing function changes in direction, the feedback, still in the original direction, opposes this and tends to persist into the original direction. This opposition delays the direction change of the process or it even cancels it when the forcing function changes direction back again before actual direction change of the process took place. Therefore, in a random process with positive feedback reverses in direction are relatively rare. The process is called persistent. While a negative feedback (due to the lag) gives an opposing feedback signal to the forcing function. So the moment when that forcing function randomly tends to change direction, it's now in the same direction as the feedback, both amplifying each other so the direction change of the process is quicker and easier than the forcing function itself. Therefore in a negative feedback situation we see more and stronger reverses in the process, the process is anti-persistent. So we could make a chaotic random model with a random walk and put various feedbacks on that to see how it changes the original chaotic signal. That is done here, Please Register or Log in to view the hidden image! The green signal in the middle is a plain one dimensional random walk. Each next step being at random between +0.5 and -0.5. For the blue graphs the indicated fraction of the former step is subtracted from the next step, simulating negative feedback with one step delay. For the warm colors, orange - red - brown graphs, the indicated fraction of the former step is added to the next step to simulate positive feedback. As expected the blue negative feedbacks resist steps away from the starting position while the reddish positive feedbacks 'amplify' it. But also as expected, the positive feedback graphs are smoother than the original green signal, showing the resistance to direction change, while the negative feedbacks show an increasingly strong ripple or noise, illustrating the assisted heading reversals, the antipersistence. So we can test the harsh reality on the sign of the feedback in any chaotic process, by just check the data and count heading reversals (up / down, below average, above average, etc) versus non reversals for every step. And guess what? http://www.aai.ee/~olavi/EE2007-ok.pdf http://www.aai.ee/~olavi/E-Ac-Sci-07.pdf No trace of positve feedback anywhere, so far. None whatsoever
Nice work Andre. I only read your first link paper, but you make a good summary of its main point in your two posts. Yes, it does seem that testing via model instead of by real data has gotten the net feed-back term wrong. I.e. it is negative, not positive feed back. However, I think you and most others would agree that the increase of GHG is "stressing" the stabilizing capacity of the negative feed back systems. Furthermore, some of these negative feed back mechanisms are being attacked. For example, the effect man's release of CO2 on GW is resisted by the natural processes of green plants, such as trees. -With higher CO2 concentrations (assuming that is rate limiting and not some soil nutrient) then the effect of the increased CO2 is reduced by the faster growth of trees etc. We in Brazil are responding to a feed back also - foreigners are sending money here to buy our trees (even in pulp form for their news papers and cardboard boxes). Thus, some Brazilians are cutting them down mainly illegally in response to the economic feed back. This is an example of the "attack" on the stabilizing natural negative-feed-back system I spoke of. Even without this and other attacks on the negative feed back system, there are limits to its ability to compensate for the increased driving forces, such as more GHGs that man is making. The real question, IMHO, is are we likely to exceed the natural system's negative feed back stabilization capacity with increasingly excessive positive driving forces, such as GHGs, burning trees, clearing land for farms (exposing buried carbon, releasing CH4 and NOx by microbes working on the fertilizer used.), etc.
Uh, Andre, the entire analysis depends on the time scale, the mechanism, and the fluctuations of the drivers being checked. Otherwise, those papers have just demonstrated that negative feedbacks probably exist in the Earth's climate system - not exactly news. And there is no mechanism, or drivers, specified. Meanwhile, the time scale has been mined - searched through at various resolutions, without justification by the properties of a postulated mechanism or underlying driver. That is not a reliable manner of handling data. And this is the third time those problems with using those particular papers to draw the conclusions you draw has been pointed out to you. Lights on yet ? You have to specify the time scale and mechanism involved to use that for prediction of the future. Getting the "net feedback direction" - whatever that means without a time scale or mechanism - wrong should produce wildly wrong (qualitatively wrong) predictions in just a couple of cycles. (Checking that depends, of course, on the lenghs of the cycles). I note that you seem to have missed Andre's point - he is arguing that the effects of the CO2 boost will not be amplified by water vapor, methane, etc or by qualitative changes in ice cover, saline circulation, etc. Do you think he is correct, in making that claim from those papers ?
I'll elaborate the remarks later, but when logaritm meets exponential there is a pretty strong brake on the mechanism. And I challenge anybody to find a persistent data series on any time scale. Take for instance the seasonal sea ice change, even that is non-persistent, despite the logical positive feedback due to reflexitivity.
And there is almost certainly a net brake on the temperature increase possible from the CO2 accumulation, even amplified as it will be by water vapor etc. The question is - where does it level things off? The usual answer is - somewhere between another degree from now and another six degrees from now seems likely. Within a hundred years or less. Depending on dominant mechanism etc. And that of course will create all kinds of serious problems for the 6 billion humans, most of whom live near water, depend on temperature and rainfall sensitive agriculture, and have no where else to go in practice. The past hundred years has shown a general upward trend in global temperatures, so far unexplained by "natural" causes.
I am not sure Andre or the supporting references he cites are correct, but think his point that one must look to the real world, not a very complex model, with lots of quite arbitrary parameters is 100% valid. One of my college professors was explaining the dangers of accepting a theory because it gave, with a few adjustable parameters an excellent fit to some real data. He said: "With only 4 parameters I can make a curve that looks like an elephant, with one more, I can make its trunk swing."* I do not think either Andre or his reference links are claiming to know the level of detail you are asserting. I.e. they are looking for the NET feedback, not trying to decompose it into "x% due to water vapor, y% due to methane, z% due to etc. and changes in the ice cover ..." -your text I made bold. I am strongly convinced that all models have so much in them that is very ill known (and probably several important aspects totally ignored) that they are essentially useless. Let me illustrate with just one aspect of the CO2 "ocean absorption sink." What area should be the contact surface for the adsorption transport of atmospheric CO2 into the ocean? Certainly, this area is very important in determining how fast Co2 is removed for the air. Also certainly it is far different from the gross area of the oceans (I.e. is not surface of Earth times the fraction of the Earth covered by water.) There is a great deal of transfer surface, probably more than half of the air / water interface INSIDE the ocean in the form of tiny bubbles. Furthermore as these bubbles dissolve, their radius contracts and surface tension can greatly increase the internal pressure. The rate at which CO2 enters the water is essentially linearly related to the pressure in the gas phase. Thus, not only is the surface to volume ratio of the very tiny bubbles much greater than the ones that are a millimeter or larger, but also when the internal pressure is two times atmospheric, the tranport rate per unit surface area is doubled. I doubt if any model has valid grounds (accurate to 10%) for the value of the surface area of the ocean that it assumes. This is just one of hundreds of such "more than 10%" errors. Why should I believe such ill understood sometimes politically motivated, model results? I much prefer the approach Andre is advocating. - Problem is to complex, well beyond current human understanding to accurately model, especially as it is the net difference in between inter-related / linked effects, some of positive feed-back and some of negative feed-back. It is sort of like trying to measure the North/South width of a NYC living room with two tape measurements: (1) The distance of the North wall from the North Pole. (2) The distance of the South wall from the North Pole. And then subtracting (2) - (1). SUMMARY: If you want to know whether or not the NET feedback is positive or negative to the current driving forces, then look at the real data, not some highly questionable models. - They can make the elephant’s trunk swing any way they want by slight "adjustment" of only 5% of their assumed parameters! ------------------- *He continued on something like: Start with equation for a circle. The first parameter can give it two legs, tail and trunk, but they will all be the same size. Second parameter can make the tail smaller, add ear "loops" and the trunk longer. Third will refine these, flatten the bottoms of the legs and thicken the legs more than tail and trunk, and I still have parameter 4 to improve its appearance.
As we argue as to who is right and who is wrong over 6 billion tones of pollutants are being put into the airways around the Earth, over 8 billion tons are being put into the oceans around the world yet we argue as to whether or not there is a problem. There is a very dangerous problem that affects everyone , everywhere yet those who make all of the money don't want us to think that is what is really going on. Perhaps the greenhouse gases aren't going to warm us , but I'll guarantee you that all of the other pollution will. Try putting that into an equation and coming up with more bullshit that tells everyone that we are all goinmg to be OK because it is a natural thing happening to us. We are all doomed and it is only a matter of time before everyone will be so contaminated that death be or only escape from the pollutiion everywhere on Earth. Please Register or Log in to view the hidden image!
Is that just "newspaper news" repeated, or do you have some supporting evidence? If you do, is only by computer model? - See my post 7 to understand why that type of "evidence" is not persuasive to me. Both the water and the air in major US cities is much cleaner today than it was two generations ago when my grandfater was alive and part of the "industral revolution" - He surved, despite what your assert - I am evidance of that. Please Register or Log in to view the hidden image! Do not mis understand - I agree polution is "bad" will caused deaths. etc. but so do automoble accidents, building fires etc. - modern life is better, I think. If you disagree, see if some Amish group will take you in.
I'd think that if you don't understand what pollution is by now and how much of it we are putting into the environment, then you are beyond educating. Just Google it and see for yourself, I don't need to become enlightned, you do.
I am reasonably well informed about pollution. For example I eat a lot of sardines and never bigger fish like sharks because I know that Hg concentrates in their bodies as it moves up the food chain. You posted before I added the suggestion for your avoiding much of the ill effects of pollution in my reply. I doubt if you will take that option as you too probably believe that in net the modern life is better, despite the deaths caused by some aspects of modern life. Here is what you missed again: "Do not misunderstand - I agree pollution is "bad" will caused deaths. etc. but so do automoble accidents, building fires, etc. - modern life is better, I think. If you disagree, see if some Amish group will take you in. "
We are talking about heavy metals, sulphuric acid, and many other pollutants that will cause GENETIC defects for humans being born in the future. There's not going to be anywhere on this planet that won't be affected adversely. In your shortsightedness I can see a business man telling us all is well, accept a few problems just as in the past. That won't stop the inevitable from happening, your children's children's will be the ones who are going to suffer the greatest if we don't stop polluting today.
I only mentioned Hg (mercury) and that is a "Heavy metal" so yes we were speaking of heavy metals and other pollutants. Solar cell production makes a lot of pollutants, but I am inclined to think that the net effect is beneficial for humans. You do not seem to understand that all of the trappings of the modern world have some negative aspects. To help you understand that, I mentioned the killing cars and buildings do in prior post. The fact is that for most locations, man's release of heavy metals is not causing even measurable increase in genetic defects. - Certainly less than cosmic rays do to airplane pilots. The airplanes themselves are quite a source of pollution. - Again, as I suggested before, if you want go live like the Amish do, you can. - Do not ride in any car or airplanes, do not use any battery operated device (your computer has at least two) so I guess you will not be replying but be careful how you dispose of it.
No, if you want to find the total effect of the feedbacks on a forcing signal in a process, you need to 'auto correlate' the output with intervals comparable to the time constant / delay of the feedback, which can be hours looking at the diurnal cycle like cumulus clouds developing hours after sunrise shielding the sun and providing negative feedback. It can also be centuries in the case of the glacial cycles preceeding the CO2 reacting after some 200-800 years. That's the very thing that appears to be falsified, if the net effect of all feedbacks is negative then the greenhouse effect of CO2 will be less than the basic value for doubling of about one degree. Hardly something to get heated about. Not in a million years. The dominant mechanism is the Clausius Clapeyron relationship, which boils down to exponentially more evaporation with temperature increase for maintaining constant relative humidity and that brake on the extra watts/m2 is likely the most dominant negative feedback system, which would have no problem smothering the logarytmically increasing IR back radiation. That's the start of the fallacy of the restricted choice, the second sentence usually being so it must be anthropogenic. That may or may nt be so, but it cannot be not predominantly greenhouse effect. There may be several more verctors we have no idea about, like changing cloud pattterns, interaction of the known cycles (ENSO, NAO, etc), aircraft contrails, changing the environment of the weather stations (Anthony Watts), direct produced anthropogenic heat.
//"The dominant mechanism is the Clausius Clapeyron relationship, which boils down to exponentially more evaporation with temperature increase for maintaining constant relative humidity and that brake on the extra watts/m2 is likely the most dominant negative feedback system"// Your insistence across the blogosphere than evaporation must go up as rapidly as Clausius-Clapeyron is simply nonsense. Readers can see at the bottom of page 5 (http://www.gfdl.noaa.gov/~ih/papers/hydro_revised.pdf) that this is simply not the case. I also invite readers to start understanding these fallacies at the top of page 153 in http://geosci.uchicago.edu/~rtp1/papers/CaltechWater.pdf Engineering and climate feedbacks are a bit different. Andre might have you believe that positive feedbacks necessarily lead to runaway effects (in a forum a long long time ago, he said I had no other choice), but this is not the case. Moreover, you cannot determine global feedbacks from the statistics of a single weather station, and the feedbacks during the deglaciation were extremely complex and not reducible to CO2 + T. During the younger dryas cold period (which andre insists never happened because he has falsified ice cores as well) there was feedback due to catastophic release of lake water from a melting ice sheet, and there are enormous ocean changes, ice sheet, vegetation and dust changes - none of which are simple functions of the orbital forcing or CO2. Equilibrium feedbacks (i.e., climate sensitivity) are best determined from near equilibrium conditions (that's why the Last Glacial Maximum is often used) and the values determined from the paleo record are a pretty good match to those determined from current models. From the last ice age, the forcing totaled about 6½ W/m2. This forcing maintained a planet 5°C colder, implying a climate sensitivity of ~¾°C per W/m2 which most models now close in on, and which the paleo record supports- See any of the postings here: http://www.realclimate.org/index.php/archives/2004/12/index/#ClimateSensitivity For further discussion on feedbacks, and the published literature from the best scholarship on the subject (which may or may not include that in "Energy and Environment," you decide) I suggest the report from the National Academies of Sciences on climate feedbacks, as well as Soden, B.J., and I.M. Held, 2006: An Assessment of Climate Feedbacks in Coupled Ocean–Atmosphere Models. J. Climate, 19, 3354–3360. Bony, S., R. Colman, V.M. Kattsov, R.P. Allan, C.S. Bretherton, J.-L. Dufresne, A. Hall, S. Hallegatte, M.M. Holland, W. Ingram, D.A. Randall, D.J. Soden, G. Tselioudis, and M.J. Webb, 2006: How well do we understand and evaluate climate change feedback processes? J. Climate, 19, 3445-3482, doi:10.1175/JCLI3819.1 Del Genio, A.D., 2002: The dust settles on water vapor feedback. Science, 296, 665-666, doi:10.1126/science.1071400 People can do these, or they can do andre's graphs and engineering analogies. I've responded to him too much, and I suspect he already knows the many errors in his posts, but still goes across numerous sites to respond to various audiences on the conspiracy that is AGW. This is my final response to him. Chris http://www.chriscolose.wordpress.com
To Chris C: I skimed your website. You seem to have much more faith in the models than me, even doing some your self, it seems. What is the effective area of the ocean for the adsorption of CO2 that you beleive true? What "one sigma error bars" to you think apply to your value?
