Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings

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

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  2530  2531  2532  2533  2534  2535  2536  2537  2538  2539  2540  2541  2542  2543  2544  2545  Next

Comments 126851 to 126900:

  1. CO2 has been higher in the past
    Philippe. It only took one man, Isaac Newton, to point the world in the right direction about the basic laws of physics. Later again, only one man, (Einstein), to introduce important caveats. On the other hand, with the smoke and mirrors theory, an international commitee has been invoked to establish its credence, and now you talk about "low blow" creationist tactics? Why a commitee? Why not just one man?
  2. CO2 has been higher in the past
    re #14 O.K., you don't believe in the greenhouse effect RSVP. The arguments you employ to try to support that astonishing position are weak 'though. You seem to be attempting to insinuate that Arrhenius's insight (which we know to be fundamentally correct) can be made to appear incorrect by reference to his views on sociological aspects of human evolutionary genetics. Your numerology is suspect, and perhaps that's partly why you don't find the greenhouse effect "intuitive". For example it makes rather more sense to consider the temperature variation throughout the last 500 million years (the Phanerozoic), a variation of the order of 10 oC (minimum to max). It’s variation within that temperature range that is relevant to the role of CO2 variation in modulating the greenhouse effect. After all we know (more 19th century science!) that a “naked” atmosphere-free earth has a temperature of around 255K from its cosy location near the sun. When considered in that light, a temperature increase of 1 oC as a result of a 34% increase in atmospheric CO2 concentration doesn’t seem so puny. It's already around 10% of the entire temperature variation of the last 500 million years, and pretty much what we expect within our (and Arrhenius’s for that matter) understanding of the greenhouse effect…
  3. CO2 has been higher in the past
    RSV #15, I may have misunderstood your comment, because I don't see the point of the Stefan–Boltzmann law here. I thought you were doing a (empirical) rule of three, suggesting that a 36% increase of CO2 (empirically) drove a (small) 0.34% change in temperature with reference to the absolute zero (i.e. percentage of change in the kelvin scale). (Leaving aside the fact that the equilibrium temperature is higher) that's why I asked what the point was in assessing the temperature change as a difference from the absolute zero.
  4. Philippe Chantreau at 06:48 AM on 29 October 2009
    CO2 has been higher in the past
    That's funny. RSVP is attempting an ad-hom on Arrhenius that is somewhat reminiscent of what we see with creationists. "Establishing this man's credibility"? The rethoric is getting down to the most miserable levels. Whether there was resistance to his CO2 ideas and the presence of other non related stuff has no bearing whatsoever on the validity of the physics involved, which can not be disputed. The initial formulation may not have been totally accurate, but the principles were correctly understood. That is an objective fact. Arrhenius could have been a paranoid schizophrenic, he would still have been right on this subject. The fact that some things are not intuituve to you is exactly why this site's focus is on science papers published by researchers active in their field.
  5. CO2 has been higher in the past
    Peter Pan Radiation energy is proportional to absolute temperature.
  6. CO2 has been higher in the past
    Chris, Being on the board of an institute specifically created to promote pseudoscience isnt exactly "periperal". Eugenics may be considered politially incorrect now, but at that time he was promoting it as respectable science. My comment is about judgement, not politics. Secondly, I never said anything about a linear relationship. I was only giving my opinion that a ratio of 0.0094:1 (i.e., .0034:.36) doesnt seem to reflect considerably tight coupling. Which is a completely separate issue from CO's atmospheric molecular mass percentage of 0.045, and the fact that CO2 absorbs energy from only a fraction of the IR spectrum. And after considering all these small values taken together, whether logarithmic or seismic or however you want to package it, the CO2 greenhouse theory (or smoke and mirrors theory or however you want to call it) is definitely not intuitive to me.
  7. How do we know CO2 is causing warming?
    Henry Pool @ Riccardo on 122 You are doing the same thing! You did not provide me with any figures!!! There is no science in any thing you say and you do not provide any logical scientific answers.
  8. CO2 is not the only driver of climate
    Gord, Your problem appears to start in this line "Substitute (4*pi*Re^2) for (Pi*Re^2) to get Earth as a "sphere" " In this step you don't do what you have done above, you should equate what Earth absorbs as a disc (from the Sun) to what it emits as a sphere to space. (4*pi*Re^2) does not equal (Pi*Re^2) so when you substitute it in you are changing the value. (Obviously, you can only substitute two quantities that are equal). A brief scan of the rest of your work seems to show that it is fine, but the Earth does not *absorb* as a sphere, it *emits* as a sphere. Cheers, :)
  9. How do we know CO2 is causing warming?
    Henry Pool, now I anticipate you won't bother looking in that AGW Observer site's index, either. So here is a link to that site's collection of papers on CO2's absorption properties in the atmosphere, to complement the link I already gave you on laboratory measurements.
  10. How do we know CO2 is causing warming?
    Henry Pool, I anticipate that you will object that those papers I just pointed you to are too narrowly focused. You need to also look at the Index on that AGW Observer site. Again, I will save you the labor. This time I'll even save you the labor of copying and pasting the URL by providing a link.
  11. How do we know CO2 is causing warming?
    Henry Pool, the top of the original post on this page you are reading now has a green box immediately before the Comments section. In that box, our host John Cook already provided a link to a collection of a large number of the scientific papers reporting the empirical measurements that you keep claiming don't exist. Since you don't seem to like to exert the labor to look where people point you, I'll repeat the link here: http://agwobserver.wordpress.com/2009/09/25/papers-on-laboratory-measurements-of-co2-absorption-properties/
  12. CO2 has been higher in the past
    RSVP, When you turn on your heating at home, do you also set your target temperature as a significant percentage change on a kelvin scale? I cannot see any sense in assessing the magnitude of a temperature change as the relative difference from absolute zero, that's an arbitrary point. Why not celsius scale instead (i.e. freezing point of water instead of absolute zero)? What is important is that it shouldn't deviate from the average value in which human civilization has thrived. That's the dangerous boundary.
  13. How do we know CO2 is causing warming?
    Henry Pool, you really think that the IPCC is stuck on a 19th century experiment? Do you really think that no one has measured CO2 absorption since then? Do you really think that more than a century of science has passed in vain? Many people here showed you how things work, but you didn't notice, as you didn't notice a century of science indeed. You didn't put any effort to find yourself the numbers (there are plenty around) you're asking for. You "suspect", "think" or "presume" a lot of things, based on nothing, and are surprised that people tells you "go and do some studying". Knowledge does not come doing nothing and if you want to do nothing forget knowledge. It is then your attitude that makes your questions un-answerable, you will keep thinking forever that "nobody could think of a way to test it properly" (sic) untill you find the will to learn.
  14. CO2 has been higher in the past
    This is an odd thing to say RSVP: "A 36% increase in CO2 to a roughly 0.34% (1 degree K/290 degree K = .0034) change in global temperature doesnt seem to indicate strong coupling." The three fundamental errors in that statement are ones that Arrhenius would have recognised over 100 years ago: (i) the relationship between earth temperature and atmospheric CO2 is not linear. The temperature varies according to the logarithm of the CO2 variation as Arrhenius had already deetermined in 1896. (ii) The relationship between earth temperature and the logarithm of the change in [CO2] refers to an equilibrium response. (iii) The temperature scale is not a linear one with respect to heat content, and it's very easy to produce spurious arguments based on misunderstanding this. The non-linearity of temperature can be illustrated by the observation that the rates of chemical reactions broadly double with each temperature increment of 10 oC. Thus a reaction that has a rate constant of 1 (say) at zero oC, may well have k=2 at 10 oC, 4 at 20 oC, 8 at 30 oC, 16 at 40 oC, 32 at 50 oC and so on... Arrhenius knew this too... If we're going to use arguments to assess relationships in the natural world, we should base these on physics that is at least at a late 19th century level!
  15. How do we know CO2 is causing warming?
    I think the 1.7 comes from the total average global warming measured (since 1750?) and the greenhouse gases (and anti greenhouse gases) are assigned a value based on their increases or decreases since 1750. I think it is not based on any specific testing on carbon dioxide that would show us exactly how much of the sun's- and how much of earth's radiation is being blocked by CO2. As far as the science goes, I think it is presumed (by the IPCC)that Svante Arrhenius "science" was right or partly right. IF THAT IS THE CASE, THEN THAT IS WRONG SCIENCE. We need to re-visit this. Svante's equipment must have been so poor, that he could have made big mistakes and he could have been completely wrong. I think he worked with 100% CO2. We need to test at certain concentrations, in the range from 0.01 to 0.06 % CO2....We need to know where we are with this and where we are going, even if the nett effect of carbon dioxide is warming (which I doubt).....None of you have convinced me yet with any numbers on the table that show that CO2 is to blame for global warming. I need to see actual figures from actual measurements taken during actual experiments. To think I started out 3 months ago, believing that CO2 is the problem! Now I am a total skeptic. It is because there are no figures when it comes to CO2. How is this possible? I suspect nobody could think of a way to test it properly. So there are only stories. Nothing but stories. And if you do not "believe" those stories you will be told by the "believers" to go and do some studying...... Is there anyone out there who can show me exactly how the 1.7 was arrived at? It just cannot fall out of the air somewhere (right into this site).
  16. CO2 has been higher in the past
    I don't think the political views of a scientist 100-plus years ago has much influence on our perception of his understanding of the physics of processes in the natural world RSVP. That sounds like a very modern concept (attempting to trash science that one doesn't like by reference to peripheral political or character traits in individuals)! Arrhenius was pretty much spot on in his understanding of the relationship between atmospheric CO2 (carbonic acid in his terminology from the manner in which CO2 concentrations were then determined) variation, and the earth temperature response, recognising that the temperature varies according to the logarithm of the CO2 concentration change: Arrhenius: "if the quantity of carbonic acid increases in geometric progression, the augmentation of the temperature will increase nearly in arithmetic progression" [*] The reason that he didn't consider increased CO2 particulalry problematic is that in his time atmospheric CO2 concentrations were rising very slowly indeed. He considered that doubling of atmospheric [CO2] would take about 3000 years. We now know that mankind can very easily achieve this massive amplification in a century and a half. In fact the concerns relating to massive enhancement of atmospheric [CO2] only really began to be voiced by scientists in the 1970's, when the scale of man-made CO2 emissions began to bite home: e.g. Broecker, W.S. (1975) "Climatic change; are we on the brink of a pronounced global warming?" Science 189, 460-3. [*] S. Arrhenius (1986) On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground Philosophical Magazine and Journal of Science 41, 237–275
  17. CO2 is not the only driver of climate
    Gord, What would be the effective temperature of the Earth as seen from space? According to Wiens Law, what does the Earth radiating at 10 microns indicate as it's temperature. What is the globally averaged surface temperature of the Earth? Why the difference?
  18. How do we know CO2 is causing warming?
    Henry Pool, go back to my comment #112. Points #2 and 3 are what you call the cooling effect of CO2. They are both roughly negligible if you mind to put numbers on them as scientists working in the field do in details. The number 1.7 W/m2 forcing from pre-industrial era come from a procedure like the one you describe but pluging in real numbers. I can't see why you should not accept it given that your are simply "sure that the cooling effect is therefore as much as the warming effect." for no reason.
  19. CO2 has been higher in the past
    Excellent post, as usual. I always learn something new here. Loads of thanks!
  20. CO2 is not the only driver of climate
    Gord, no need to read it again. You did not consider the atmosphere for what it really is and that's explain, i hope, what i said. You simply did elementary calculations of the electromagnetic fluxes of an immaginary static system at fixed temperature and with no absorpion. It should be clear that it does not apply in our case.
  21. CO2 has been higher in the past
    John The cited reference in the article starts like this... "Carbon dioxide (CO2) is an important greenhouse gas, and its role in regulating global surface temperatures has been recognized for over a century (Arrhenius, 1896; Chamberlin, 1899). It is now generally accepted that the 36% rise in atmospheric CO2 since 1860 (280–380 ppm) is partly responsible for the concomitant rise in global surface temperature" If you looked up the Wikipedia reference on Arrhenius, you will find he met resistance for his idea. So to say that his idea was RECOGNIZED is an overstatement, especially with whatever data he had in 1896! Also, in terms of establishing this man's credibility, the Wikipedia article includes a little more. It goes on to say that Arrhenius apparently felt that global warming would be a good thing in that it would help world food production. In addition, he apparently supported the following... Wikipedia on Arrhenius... Racial biology "Svante Arrhenius was also actively engaged in the process leading to the creation in 1922 of The State Institute for Racial Biology in Uppsala, Sweden, which had originally been planned as a Nobel Institute. Arrhenius was a member of the institute's board, as he had been in The Swedish Society for Racial Hygiene (Eugenics), founded in 1909. Swedish racial biology was world-leading at this time, and the results formed the scientific basis for the Compulsory sterilization program in Sweden, as well as inspiring the Nazi eugenics in Germany" ''''''''''''''''''''''''' Getting back to Dana Royer's intro... A 36% increase in CO2 to a roughly 0.34% (1 degree K/290 degree K = .0034) change in global temperature doesnt seem to indicate strong coupling. In fact, it tends to signal that there is quite a lot margin for continued CO2 polluting.
  22. CO2 has been higher in the past
    RSVP, it looks like you think that scientist are stupid or that you don't trust science at all. Comparing what solar physicists know on our sun (on all the stars) to scientology means that you did not even try a wikipedia search for stellar evolution, let alone scientific papers. They might of course be wrong, but this is what our scientific knowledge tells us. And one needs scientific arguments to contend.
  23. CO2 is not the only driver of climate
    shawnhet - re: your posts #74 and #75 Here is the derivation of the equation. BC = Boltzmann's Constant Te = blackbody temp of the Earth Ts = surface temp of the Sun Rs = radius of the Sun D = distance between the Sun and Earth a = albedo of the Earth Psemt = (BC*Ts^4)(4*pi*Rs^2)....energy emitted by the Sun Peabs = Psemt(1-a)(Pi*Re^2)/(4*pi*D^2)....energy absorbed by the Earth as a "disk" Substitute (4*pi*Re^2) for (Pi*Re^2) to get Earth as a "sphere" Peabs = Psemt(1-a)(4*Pi*Re^2)/(4*pi*D^2)....energy absorbed by the Earth as a "sphere" Peabs = (BC*Ts^4)(4*pi*Rs^2)(1-a)(4*Pi*Re^2)/(4*pi*D^2)....energy absorbed by the Earth as a "sphere" after replacing Psemt. Peabs = (BC*Ts^4)(4*pi*Rs^2)(1-a)(Re/D)^2....energy absorbed by the Earth as a "sphere" Peemt = (BC*Te^4)(4*pi*Re^2)......energy emitted by the Earth as a sphere Equating... Peemt = Peabs gives: (BC*Te^4)(4*pi*Re^2) = (BC*Ts^4)(4*pi*Rs^2)(1-a)(Re/D)^2 (BC*Te^4)/(BC*Ts^4) = (1-a)(Re/D)^2(4*pi*Rs^2)/(4*pi*Re^2) (Te/Ts)^4 = (1-a)(Re/D)^2(Rs/Re)^2 Taking the square root of both sides gives: (Te/Ts)^2 = (1-a)^0.5(Re/D)(Rs/Re) (Te/Ts)^2 = (1-a)^0.5(Rs/D) (Te/Ts)^2 = ((1-a)^0.5 *Rs)/D Taking the square root of both sides again gives: Te/Ts = ((1-a)^0.5 *Rs)/D)^0.5 Te = Ts (((1-a)^0.5 *Rs)/D)^0.5) And what I posted was: TE = TS (((1-a)^0.5 * Rs)/D)))^0.5) Which I typed too many brackets in, but does not change the result. This equation gives the temperature of the Earth at the equator. Hope this helps.
  24. CO2 is not the only driver of climate
    Riccardo - Re:your Post #73 You said... "You are compleately missing that there is earth, there is the atmosphere and there is empty space outside. Consider the whole system, not just a piece of it." "Yes, all the bodies at a certain temperature will radiate a fixed amount of energy. No doubt. But again, you are not considering atmosphere and free space and then the total energy balance." Read my post #69 again...the Earth, atmosphere and cold space were all included in the calculations.
  25. CO2 has been higher in the past
    To #5: As you mention yourself: If you extrapolate the average sea level rise of the last 40 years, you'll get up into that interval in a few thousand years. Which is not to say that is what will happen, we may have negative feedbacks, like clouds and (possibly) aerosols. On the other hand, there may be positive feedbacks kicking in significantly, too. Like the mentioned CO2/sea water temperature relation. Remember, the forcing from radiation imbalance we have now is very small compared to the natural seasonal and cyclical variations, and the effects are to be seen on longer time scales.
  26. CO2 has been higher in the past
    To be able to say the Sun was 4% cooler 540 million years ago assumes linearity associated with a slope of 0.04 divided by 540 E+6, which equals 7.4 x E-11. Is this based on science or scientology?
  27. CO2 has been higher in the past
    I have a question about the Tripati paper I hope somebody can answer. If CO2 levels are about the same today as 20 million years ago and I guess from what is said in this article the sun is a little warmer thn 20million years ago as well then where is all the water? Why don't we have 3-6oC higher global temperatures and 75 to 120 feet higher sea levels. Thats 2200-3000cm of sea level rise. Given an estimate of sea level rise was 3cm for the previous decade that means we'd have to wait 1000 years for that publications prediction to come true. Why aren't sea levels that much higher? Maybe not knowing all the conditions 20million years ago might have something to do with it?
  28. How do we know CO2 is causing warming?
    In that case I have to bear in mind the absorption of water at 14. The % of water in the air can be easily 1% on average compared to the CO2 of only 0.035%. If I look at it that way then there is only a tiny little corner of earth's radiation at 14 that is not being emitted. The gaps in the sun's emittance caused by the CO2 are the same size , in total, if not more. I am sure that the cooling effect is therefore as much as the warming effect. The problem is: there are no real figures when it comes to carbon dioxide. No proper research has been done. It is all just stories. Some infatuation with a viking who lived many years ago and whose results have been proven wrong. I have been going around asking the same questions and not getting any measured results. In fact, many "scientists" would not believe me when I told them that CO2 causes cooling (during daylight) You did not answer the question on my post at 117: It seems we are going around in circles. I went to the subject: "CO2 not the only driver of climate change" on this site that was recommended by you and I could not figure out where this 1.66 (1.7) came from. That 1.7 is a weighted figuire, is it not?>
  29. CO2 has been higher in the past
    Commenter #1 misses the point of this blog post -- with a weaker solar forcing, and no CO2 causation of warmer temperatures, how could temperature be warm enough to bubble all that CO2 out of the oceans? Anyone who challenges the role of CO2 in warming the planet should be prepared to provide an alternate explanation of what accounts for warm geologic periods. The other point I was going to try making was that CO2 proxies include phytoplankton, such that high CO2 concentrations in the atmosphere are actually inferred from high CO2 in the photic zone of the oceans, contrary to the interpretation in comment 1. However, when I looked at the paper (Royer 2006, figures 1b and 3b) I noticed that there are no phytoplankton proxies for CO2 when CO2 is estimated to be quite high. I haven't read the paper yet (too many things on the go), but I found that interesting.
  30. How do we know CO2 is causing warming?
    Henry Pool, take the sun radiation at sea level, take the sun radiation outside the atmosphere; the difference will be what is absorbed by the atmosphere; then you need to consider who is abosorbing at the various wavelength. Straightforward. Then do the same thing starting with the radiation emitted by the earth and you are done. Look for the data and the calculations yourself if you mind, it won't take more than a few minutes. Though, it is just for your curiosity, becase you can be sure that this is exactly what scientists have done for a long while.
  31. CO2 is not the only driver of climate
    Gord, Upon thinking about it, I find that it is equivalent to say that one divides the energy received by the sun(1368Wm-2) by the surface area of the Earth and to use the explanation I gave in my last post. This doesn't change the fact that the following expression doesn't work to calculate the temperature of the Earth. TE = TS ( ( (1-a)^0.5 * Rs)/D) ) )^0.5) Cheers, :)
  32. CO2 is not the only driver of climate
    Gord, I agree that the Earth absorbs as a disk and emits as a sphere. However, that fact is already taken into account in your **first** expression - TE = TS (((1-a)^0.5 * Rs)/(2*D))^0.5. Your second expression is mistaken(it has to be wrong if your first expression is accurate). Check the derivation of it here(about 2/3 of the way down the page). http://en.wikipedia.org/wiki/Black_body The reason for the division 1368 by 4(when you are calculating the energy **absorbed** by the Earth) is not to relate it to the surface of the sphere, but rather to average it over the day-night period and to account for the shape of the Earth (as you say here) "It is only the vector portion of the flux that is 'normal' to the surface that will cause heating. All 'normals' to a spherical surface will be on a line passing through the center of the sphere.". Cheers, :)
  33. How do we know CO2 is causing warming?
    It seems we are going around in circles. I went to the subject: "CO2 not the only driver of climate change" on this site that was recommended by you and I could not figure out where this 1.66 (1.7) came from. It just falls out of the air somewhere. It looks to me this is a weighted figure - you would only do such a weighthing if you are 100% sure of what the cause is of your problem. So this looks very familiar to the famous theory: "Let us have planet, let us add some CO2, let us see if the temperature increases, it did, so that must be it." Clearly this does not answer the simple question I am asking in 113 (although I forgot an important absorption): On my graph of the solar radiation spectrum I have clear gaps caused by CO2, especially at 1,4; at 1.8, and 2.4 (um); we know from the tables that the solar radiation carries on, so that means it also blocks some of the sun's radiation at between 3 and 4 and 5 um. In addition, I also heard that they use the UV absorption of carbon dioxide to determine the presence of carbon dioxide on other planets. So to say there is no cooling caused by carbon dioxide clearly flies in the face of all the evidence in front of me. Therefore we need specific testing that will determine how much cooling and how much warming is caused by the carbon dioxide. What we need to establish is the nett effect.
  34. CO2 is not the only driver of climate
    Gord, "All heat energy absorbed is radiated!...there is no "reducing heat dispersion" or "higher equilibrium temperature"! You are compleately missing that there is earth, there is the atmosphere and there is empty space outside. Consider the whole system, not just a piece of it. "I already explained that the Earth at +15 deg C will radiate 390 w/m^2...always." Yes, all the bodies at a certain temperature will radiate a fixed amount of energy. No doubt. But again, you are not considering atmosphere and free space and then the total energy balance. "This is an obvious subtraction of two Electromagnetic Fields." And that's what we called IR radiation, indeed. And that's what is moving energy from the sun toward the earth and from the earth to outside space through the atmosphere. It's indeed the very same flux i'm talking about. "What do you mean by "Only after this point is clear, which appers to not be the case up to now, we can continue on how the thermal insulation works in the case of the earth atmosphere." ????" I mean that if we do not first fix the misconceptions in basic physics we can go nowhere.
  35. How do we know CO2 is causing warming?
    Henry Pool, "yes, the problem is that water also absorbs where CO2 absorbs. I think it needs to be untangled." Just at some frequencies, not all. And it's not a problem, it is just a known effect that can be easily taken into account. "If so, then that is not the right type of science, because that is assuming you know exactly what the solution to the problem is." It is calculated from basic principles, not yet the solution of the problem. "You must first prove to me, scientifically, that the nett effect of the cooling and warming caused by CO2 is causing global warming." At this stage, we are not yet proving that it causes all of the observed global warming. We are just calculating forcing and than that it is at least part of it. After that other factors come into play, weighted by their relative forcing and by climate sensitivy.
  36. CO2 has been higher in the past
    thingadonta, we have quite a good handle on the temperature-dependent partitioning of CO2 between the atmosphere and oceans/terrestrial environment. One rtaher simple way of looking at this is to consider the relationship between atmospheric CO2 levels and earth temperature during the recent ice age cycles, since it's likely that the full increase in atmospheric CO2 levels during glacial to interglacial transitions results from temperature-dependent repartitioning. Looking at multiple ice age cycles, there is a generally consistent increase of atmospheric CO2 near 90 ppm (190 ppm glacial to 280 pm interglacial), and this is associated with a globally-averaged increase in earth temperature of 5-6 oC. Since these transitions are long (~5000 years), we can assume that the repartitioning has come near to equilibrium. So each degree centigrade of temperature rise "flushes" 15-18 ppm's worth of CO2 into the atmosphere at equilibrium. That's a useful "rule of thumb" in considering the likely contribution of temperature-dependent repartitioning to CO2 levels in the past. Since much of the tempeature variation during the Phanerozoic covers around 8-10 oC between coldest and hottest, we don't really expect variation of atmospheric CO2 from temperature-responsive repartitioning of more than around 150-200 ppm. Since atmospheric CO2 proxies indicate variations of CO2 levels of up to several thousand ppm of CO2, we can be pretty confident that these arise from factors other than temperature-dependent repartitioning. And when one examines the geological record, the causes of many of the large variations of atmospheric CO2 that likely dominate temperature variation, are apparent.
  37. CO2 is not the only driver of climate
    RSVP, Oh there is Global Warming, we are coming out of an Ice Age....just like we have many times before. The reason for Global Warming is the same as always...the ONLY ENERGY SOURCE....THE SUN.
  38. CO2 is not the only driver of climate
    To Gord If greenhouse warming is not real, what then do you attribute global warming to? I suppose you dont have to have a theory, but it would be interesting to know if you do.
  39. CO2 is not the only driver of climate
    I really appreciate this blog! As for this post, I wonder about two things: 1. What does the track racord until now tell us about the _net_ forcing (all feedbacks inclusive) from the CO2 increase we have had? Does it clearly show that the estimates of about 2 oC/doubling are the most plausible, given all data? (Maybe I should have known this, but I don't.) 2. Is the net feedback effect a stable and well-defined entity, or is it the average of several different terms, which may vary with a set of conditions? Has it been investigated whether variation in feedback may partially explain som of the climatic variability? ( Again, maybe I should have known this, but I don't.)
  40. CO2 is not the only driver of climate
    Riccardo - re: your post #68 You said... " But it's effective in reducing heat dispertion and this results in a higher equilibrium temperature." "...the outgoing flux is just reduced, didn't reverse." Wrong. All heat energy absorbed is radiated!...there is no "reducing heat dispersion" or "higher equilibrium temperature"! I already explained that the Earth at +15 deg C will radiate 390 w/m^2...always. The warmer Earth radiates 390 w/m^2 and heats up the atmosphere to -20 deg C. The atmosphere will radiate 324 w/m^2 in all directions...always. Between the Earth and Atmosphere the resultant EM field is (390-324) 66 w/m^2 in an upward direction. Past the atmosphere the Resultant EM field is 66 w/m^2 PLUS 324 w/m^2 for a total of 390 w/m^2 in an upward direction to cold space. ALL the 390 w/m^2 radiated by the Earth is radiated to cold space. If you removed the atmosphere, the Earth would still radiate 390 w/m^2 to cold space ! There is no "reducing heat dispersion" or "higher equilibrium temperature"! And, the "outgoing flux" IS NOT REDUCED!!! --------------------------- You said... "By the way, you used this very same concepts in #16 without even realizing it. You correctly wrote P = e*BC*A(T^4 – Tc^4); the two terms are two fluxes in the oppostite direction, one coming from a cooler body. "Only after this point is clear, which appers to not be the case up to now, we can continue on how the thermal insulation works in the case of the earth atmosphere." HUH?....P = e*BC*A(T^4 – Tc^4) = P/A = e*BC*T^4 – e*BC*Tc^4 (Watts/m^2) This is an obvious subtraction of two Electromagnetic Fields. This is EXACTLY what I used for "Between the Earth and Atmosphere the resultant EM field is (390-324) 66 w/m^2 in an upward direction." !! What do you mean by "Only after this point is clear, which appers to not be the case up to now, we can continue on how the thermal insulation works in the case of the earth atmosphere." ???? ----------------------------------- P.S. Think about this, a random sequence of correct statements HAS MADE THE CONCLUSIONS RIGHT!
  41. CO2 has been higher in the past
    @thingadonta "Isn't C02 concentration in the atmosphere strongly correlated with ocean temperatures at the time:" That is right under presumption that CO2 levels in the system (biosphere and hydrosphere)are nearly constant. You have to understand, that CO2 levels in the atmosphere and in the oceans are in equilibrium. This equilibrium is dependent on the temperature of the system. If you rise temperature more CO2 will find its way into the atmosphere, if temperature falls, the oceans will absorb more CO2. But, what will happen if you release large amounts oc CO2 into the atmosphere from sources other than the ocean? A certain fraction of this CO2 will be absorbed in the oceans and the other fraction will stay in the atmosphere, according to equilibrium. This is exactly what we see. The amount of CO2 in the atmosphere is rising and the amount of CO2 in the oceans is rising too. This is seen in every measurement in the atmosphere and in the ocean. This is a fact that is not possible to neglect. If you understand this simple connection of CO2 level, equilibrium and temperature, it will be very easy for you to understand, why rise of temperature is able to force CO2 into the atmosphere and why CO2 is increasing in the oceans despite of rising temperature.
  42. How do we know CO2 is causing warming?
    yes, the problem is that water also absorbs where CO2 absorbs. I think it needs to be untangled. Anyway, that calculation of the net forcing =1.7, that is the one based on the global warming observed to which every greenhouse gas is then assigned a value depending on the increase in that greenhouse gas since 1750? If so, then that is not the right type of science, because that is assuming you know exactly what the solution to the problem is. You must first prove to me, scientifically, that the nett effect of the cooling and warming caused by CO2 is causing global warming.
  43. CO2 is not the only driver of climate
    Gord, many people already tried to show you where your pedantic and obsessively repeated reasoning is faulty. I'll try with simpler physics that I hope you manage better. Just my two cents. The sun is heating the earth, no questions about it. Given a constant power input, a body will warm indefinitely unless there is a mechanism of dissipating it; in this case, the body will exponentially approach an equilibrium temperature. If you put a suitable thermal insulator, you reduce heat dissipation and the equilibrium temperature will be higher. Is it the thermal insulator that heats the body? Definitely not. Is the thermal insulator warmer than the body? Clearly not, there will be a temperature gradient inside it (and in the right direction, also!). But it's effective in reducing heat dispertion and this results in a higher equilibrium temperature. Does this violate thermodynamics? Absolutely not, the outgoing flux is just reduced, didn't reverse. By the way, you used this very same concepts in #16 without even realizing it. You correctly wrote P = e*BC*A(T^4 – Tc^4); the two terms are two fluxes in the oppostite direction, one coming from a cooler body. Only after this point is clear, which appers to not be the case up to now, we can continue on how the thermal insulation works in the case of the earth atmosphere. P.S. Think about this, a random sequence of correct statements does not make the conclusions right.
  44. How do we know CO2 is causing warming?
    Henry Pool, put numbers on those absorption you claim has not been considered, but do not forget the presence of other absorbing species. This is the evidence that you do not see. And as repeatedly said no more tests are nedded, they are all well know (if you mind to look for them around on the internet or in a database of optical properties). Then, based on the known numbers, the net effect of 1.7 W/m2 is calculated exactly the way you ask, taking into account the absorption properties of all the constituents of the atmosphere.
  45. How do we know CO2 is causing warming?
    Dear Riccardo, on my graph of the solar radiation spectrum I have clear gaps caused by CO2, especially at 1,4; at 1.8, and 2.4 (um); we know from the tables that the solar radiation carries on, so that means it also neatralizes some of the sun's radiation at between 4 and 5 um. In addition, I also heard that they use the UV absorption of carbon dioxide to determine the presence of carbon dioxide on other planets. So for you to say there is no cooling caused by carbon dioxide clearly flies in the face of all the evidence in front of me. Therefore we need specific testing that will determine how much cooling and how much warming is caused by the carbon dioxide. What we need to establish: what is the nett effect? Now if you can tell me exactly how the 1.7 was arrived at?
  46. CO2 is not the only driver of climate
    Tom Dayton - re:your post #66 The difference is that Adiabatic Warming does NOT VIOLATE the 2nd Law of Thermodynamics! "These clouds absorb the radiation emitted by the earth and radiate it back down toward the earth's surface, warming the air." http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/temperature/temperature_radiation_heat_p_2.html “Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object.” http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw.html#c3 Hmmm, now which one should I believe, the one that complies with Laws of Science or the one that violates Laws of Science?
  47. CO2 is not the only driver of climate
    Um... But Gord, the very same online book you just cited in comment 65 answers RSVP's question exactly the way RSVP said that most people answer it, and also explicitly states that air transfers energy down toward the surface. See http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/temperature/temperature_radiation_heat_p_2.html
  48. CO2 is not the only driver of climate
    RSVP - re:your post #63 The answer is Adiabatic Warming. Here is a link. Adiabatic temperature change and stability http://www.uwsp.edu/geO/faculty/ritter/geog101/textbook/atmospheric_moisture/lapse_rates_1.html
  49. CO2 is not the only driver of climate
    Shawnhet - re: your Post#62 Here is another way to look at it. The Solar Constant is the Solar Flux reaching the Earth before the Disk Averaging takes place. The Solar Constant for a Sun temp of 5778 K is 1368 w/m^2. To get the Earth as a Disk average you simply divide the 1368 w/m^2 by 4 to get 342 w/m^2 which is used by Trenberth's Energy Budget Diagram as the average Solar radiation at the top of the atmosphere. The 342 w/m^2 is the average Day and Night Solar insolation. The reason you divide by 4 is Area of Sphere = 4*Pi*R^2 and Area of Disk = Pi*R^2 has a ratio of 4 to 1. Without the Disk Averaging all the Solar Constant 1368 w/m^2 would be received at the Earth's equator and less at other latitudes because of the angle of the higher latitudes. Zero w/m^2 will be received at the Poles. The two equations describe the two situations. Hope this helps.
  50. CO2 is not the only driver of climate
    Question for Gord How does one explain the following... During two consecutive nights in a high desert location, there is no appreciable wind at ground level for two days. On the first night temperatures drop to 5 degrees C, while and on the second it goes below freezing. The only observed conditions at ground level between one night and the next were the high clouds of the first night. Most people usually attribute the warmer night to the cloud coverage that seems to act as a "blanket". Is there some fallacy to this model, and if so, what would be a better way to describe what is going on?

Prev  2530  2531  2532  2533  2534  2535  2536  2537  2538  2539  2540  2541  2542  2543  2544  2545  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us