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

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Comments 97951 to 98000:

  1. The Physical Chemistry of Carbon Dioxide Absorption
    @e #15 You said in your post. In fact, the key to the greenhouse effect is that CO2 doesn't readily absorb solar radiation, but does absorb infrared. You should read up on the greenhouse effect and thermal radiation. Whilst I understand what you mean, your statement is incorrect due to the terminology you used. Solar Radiation combines all types of radiated energy from the Sun, from Gamma Rays, through the visible range, into Infra-Red, into Microwaves and radio. Of course your comment about CO²'s interaction with IR is correct, but I would urge caution in how it is worded as it could be misleading, and some may jump on your comment and twist it in an attempt to suggest your saying something your not.
  2. Monckton Myth #3: Linear Warming
    @19 Dikran Marsupial: OK, have had time to have a play, and here are the results with "simple" equations:
    RankRsqDOF Adj RsqStd ErrorF-statisticEquation
    10.99958380.99953850.47308052.822e+04Quartic(a,b,c,d,e)
    20.99939020.99933830.56663072.622e+04Cubic(a,b,c,d)
    30.99937500.99933590.56777843.917e+04Quadratic(a,b,c)
    40.99210750.99143582.03850482011.2298Exponent4(a,b,c,d)
    50.98904980.98836542.37649812212.8954Exponent3(a,b,c)
    60.98740940.98689552.52268083921.2121Line(a,b)
    I have ignored monster equations like 10th order Chebyshev's and Fourier polynomials. Both 3 and 4-parameter exponentials: y = A0 + A1*Exp(A2*(X+A3)) ) are a poor fit, both visually and statistically. Monckton's beloved straight line is very poor. Using the calibrated eyeball™, it is impossible to tell the difference between the three polynomials. Tamino's log plot simply tells us that it's not an exponential rise in [CO2] - which this comparison confirms. I would suggest you have a play with TC2D: it is quite surprising how well a quadratic fits the data, especially given the limited degrees of freedom of a quadratic.
  3. Not a cite for Soare eyes
    (Re: my comment #31) Excuse me. The last link should be this. The intermediate rebuttals of No. 28 "Oceans are cooling".
  4. Not a cite for Soare eyes
    (Re: my comment #27) Here are some references about interannual variability of CO2 flux and its relationship with El Nino. (Excuse me I cannot provide more up-to-date ones.) C.D. Keeling et al. 1995 R.A. Feely et al. 1999 (Re: Leland Palmer's comment #29) The results of Knox and Douglass paper is essentially Willis's analysis of Argo data, which has already been discussed in The intermediate rebuttals of No. 28 "Oceans are cooling".
  5. The Physical Chemistry of Carbon Dioxide Absorption
    archiesteel (RE: 104), The evidence is that the cloudy sky has smaller transparent window than the clear sky, and the cloudy sky covers about 2/3rds of the earth's surface. Beyond averages though, I think areas completely covered by low clouds have almost no transparent window - meaning virtually all the emitted surface power is absorbed by the clouds. If the clouds are absorbing most or nearly all of the surface power already, more CO2 will have little effect.
  6. Monckton Myth #2: Temperature records, trends and El Nino
    WHATDOWEKNOW, I forgot... see here for clear and indisputable evidence of the two month lag between temps and MEI.
  7. Monckton Myth #2: Temperature records, trends and El Nino
    WHATDOWEKNOW, Close, but no cigar. Please provide a cite for your "strength" numbers. Everything I have seen (and a quick glance at this confirms it) says that the El Nino was moderate, while the La Nina is very, very strong. In fact, the multivariate ENSO Index (MEI) peaked at 1.502 in Feb for the El Nino, but hit -1.99 in Oct for the La Nina. In contrast (because the two values, positive and negative, do not directly compare) the 1998 El Nino hit a value of 2.677 for two consecutive months (and was 2.4/2.5 for the preceding and following months), while the previous comparably sized La Nina was -1.906 way, way back in Jan 1973, and there is no value (not one!) back to 1950 that beats the strength of the current La Nina. 1.5 for one month in 2010, versus 2.4-2.7 for four consecutive months in 1998. -1.99 for one month in 2010, versus -1.9 all the way back in 1973, and nothing else all the way back to 1950. Another indicator, the SOI, is now the highest (positive correlates to La Nina conditions) it's been since 1973, and you have to go all the way back to 1917 and 1904 to find values that are more pronounced (see here). So, again... a citation for your claims about relative El Nino/La Nina strength, please. The statements about the temperature lag are almost accurate, except that the lag relative to the MEI is only two months, not four. You can apply a four month lag to the SOI, but that flips two months sooner than the MEI. So by your logic the year was influenced by 5-6 months of the tail end of a moderate and relatively brief El Nino, and 6-7 months of the start and heart of a very powerful La Nina.
  8. Not a cite for Soare eyes
    Unless I am missing something, and I am not an expert in any field relating to climate science or statistics, even if it is correct, isn't Soares paper essentially irrelevant to the AGW hypothesis? Saores finds that there is no short term correlation between CO2 and temperature. The AGW hypothesis never claims that there will be such a correlation, in fact it expects this by using a measurement methodolgy (moving averages) to account for such short term variability.
  9. The Physical Chemistry of Carbon Dioxide Absorption
    @RW1: "This is mainly because CO2 has little effect in between the surface and the clouds, because the clouds would absorb virtually all the infrared surface power anyway." Please provide evidence that would support this assertion. Thanks.
  10. Could global warming be caused by natural cycles?
    @pirate: "I did not reference the LIA in that post. I referenced only the ice age, and it stands to reason the Earth warms coming out of a cold period." We are way past the Holocene Optimum. Temperatures should be cooling now, according to the paleoclimatic record. They aren't.
  11. The Physical Chemistry of Carbon Dioxide Absorption
    MrAce (RE: 101), "I've got the feeling that clouds are of some importance here. Since they absorb a wide spectrum of IR and radiate a blackbody spectrum depending on the temperature of the cloud. If more CO2 does not change the temperature/height/amount of the clouds, we expect the surface to warm even more, because it can only lose extra energy where there are no clouds. Is this reasoning correct?" No, I don't think so. This is mainly because CO2 has little effect in between the surface and the clouds, because the clouds would absorb virtually all the infrared surface power anyway. Where more CO2 has the highest potential to increase the surface power is also where heat most easily and quickly escapes out to space (i.e. in dry, cloudless areas).
  12. Monckton Myth #3: Linear Warming
    @NETDR: it would have been simpler if you were capable of admitting when you're wrong. Here is another version of the graph you linked to. The long-term and short-term trends have been offset to be more visible. It is clear, looking at the short-term trends, that the rate is accelerating.
  13. Could global warming be caused by natural cycles?
    WDWK @162, To be honest I really do not know what you are trying to suggest with your posts. It seems that you agree with the main thrust of the OP, so why then reiterate your straw man argument? You are raising a moot point. Tsonis et al. (2005) purport that: "Thus, in a warming climate El Nino events will be more frequent than La Nina events. That transition, if it comes to be, would act to further enhance the long-term underlying warming from the escalating radiative forcing from anthro GHGs.
  14. Could global warming be caused by natural cycles?
    #162: "I show how the ENSO pattern has changed the last 35 years and even more so the last 10 years, shifting from la nina dominated to el nino dominated events" And why do you think that is? What has happened that could shift a fairly regular oscillation so dramatically? From Yeh et al 2009, el Nino in a changing climate: Recent studies show that the canonical El Niño has become less frequent and that a different kind of El Niño has become more common during the late twentieth century ... the central Pacific El Niño (CP-El Niño; ... ), differs from the canonical eastern Pacific El Niño (EP-El Niño) in both the location of maximum SST anomalies and tropical–midlatitude teleconnections. ... we find that projections of anthropogenic climate change are associated with an increased frequency of the CP-El Niño compared to the EP-El Niño. ... the occurrence ratio of CP-El Niño/EP-El Niño is projected to increase as much as five times under global warming. -- emphasis added So given that you agree that AGW exists (ref #158); what was once a 'natural cycle' may no longer be so natural.
  15. Klaus Flemløse at 07:57 AM on 19 January 2011
    A Quick and Dirty Analysis of GHCN Surface Temperature Data
    I will be pleased if someone could tell me how to the read the GHCN-data using the R-program. Could not find it on the internet !
  16. Could global warming be caused by natural cycles?
    #161. Why did they use MEI? That's a ranked-value, based on 6 variables many of which not related or only indirectly related to temperature. MEI is not an actual measurement. MEI is not a temperature anomaly, such as NOI or SOI. hence, I don't see how subtracting a rank from a temperature anomaly produces anything meaningful. Please explain if it does.
  17. Could global warming be caused by natural cycles?
    #160, thanks but I am not saying climate scientists are ignoring or denying these cycles. I am referring to this original post that claims: "As we can see, "it's just a natural cycle" isn't just a cop-out argument - it's something that scientists have considered, studied, and ruled out long before you and I even knew what global warming was." which I find to be a strong argument and therefore I am saying "Just because there may be AGW doesn't mean global natural cycles have no influence on global temperatures anymore. They always have and always will." I am saying nothing more, nothing less with that statement. I am not accusing anybody with that statement either, it's simply open and true. I am sorry you misinterpreted it and perceived it the way you did. Of course does an el nino alone or all el ninos combined for that matter not explain the current temp anomalies. I never stated that either. But we agree that el ninos and la ninas significantly affect global temperatures. That said, please look again and my comment #137 where I show how the ENSO pattern has changed the last 35 years and even more so the last 10 years, shifting from la nina dominated to el nino dominated events. How does that fit in is my question.
  18. OK global warming, this time it's personal!
    muoncounter at 03:22 AM on 18 January, 2011 re "after the flood, first come the home repair scam artists, then the cheesy lawyer commercials" The changes AGW have wrought! In earlier times it was astute stockmen that came after the flood, bringing large cattle herds to fatten on their way to market, grazing the prolific grasses that grew as the flood waters receded from the natural flood plains, leaving newly moistened and nutrient rich soil that early fortunes were made upon.
  19. Could global warming be caused by natural cycles?
    WDWK @ 158 - You should read this Tamino piece, which Daniel Bailey noted here. Accounting for and correcting the various known cycles, the underlying trend is very clear.
  20. Monckton Myth #3: Linear Warming
    NETDR: "I am only looking at 90 years because we will have transferred to renewable fuel by then" If there is no problem with continuing to pump CO2 into the atmosphere at the current, accelertaing rate, why would we switch to renewables?
  21. OK global warming, this time it's personal!
    barry at 23:39 PM on 17 January, 2011, perhaps the best of all handy references that enables rainfall Australia wide to be put into perspective at a glance, is a wall chart published by Queensland Natural Resources and Mines. Pictorially it displays annual rainfall Australia wide relative to historical records 1890 - 2004 with updates available for each succeeding year to present. Unfortunately it is no longer available as a wall chart as it would be of great assistance to those trying to interpret recent events in relation to historical records using graphs or statistics which don't convey the full picture and can easily be misinterpreted.
  22. Could global warming be caused by natural cycles?
    WWDK @158, "Just because there may be AGW doesn't mean global natural cycles have no influence on global temperatures anymore. They always have and always will." You are making a classic strawman argument there. Nobody int he know here is denying that the climate system has internal modes (e.g., ENSO, AMO), nor are they denying that they do modulate global SAT record to some extent. What these transient internal climate modes (which are cyclical by nature) do not explain is the sustained, long-term warming that is observed in the SAT record. An El Nino alone does not explain the current global SAT anomaly of +0.63 K (GISTEMP) relative to the 1951-1980 baseline, nor does it explain the +0.85 K warming observed since circa 1880. ENSO perturbs global annual SATs by about +/- 0.1 K, and at most about +/- 0.2 K for a strong event (Trenberth et al. 2002). From Tsonis et al. (2005): "Note that the contribution of ENSO to the long-term temperature trend in the last 50 years is about 0.06 C or 10% of the overall trend [Trenberth et al.,2002].However, as Figure 2a indicates, after a time scale of the order of 16 (5 + 11) months, El Nino’s role is to reverse that tendency." So much for the (false) claim made here and elsewhere that natural cycles are being "ignored" by climate scientists. To suggest so is incredibly patronizing to climate scientists.
  23. Monckton Myth #2: Temperature records, trends and El Nino
    The response lag-time between atmosphere and ENSO events is well-known to be 3-4 months (e.g. here). Hence, one has to look 3-4 months ahead in time to see how global temperatures start and end to respond and not compare month to month values. That said, the previous el nino started officially June 2009 (month 6 of 2009) and lasted until April 2010 (month 4 of 2010). The current la nina started officially July 2010 (month 7 of 2010). Let's take a look when the global atmosphere started to respond to both events using first the lower bound response: 3 months and then the upper bound response: 4 months. 3 months lag El Nino: atmosphere started to respond September 2009 (month 6+3=9) 2009 and ended to respond July (month 4+3=7) 2010. La Nina: atmosphere started to respond October (month 7+3) 2010. 4 months lag El Nino: atmosphere started to respond October 2009 (month 6+4=10) 2009 and ended to respond August 2010 (month 4+4=8). La Nina: atmosphere started to respond November 2011 (month 7+4=11). Now these are lower and upper bound assumptions, but it shows that 2010 was influenced between 7-8 months out of 12 by the previous el nino and between 2-3 months out of 12 by the current la nina. Hence, it is safe to say that 2010 was mainly influenced by the previous el nino and not the current la nina. Taking also into account that the past el nino had a peak strength of 1.8, whereas the current la nina's peak is -1.4, it is even more save to say that the el nino had both a longer and stronger effect on 2010 than the current la nina.
  24. apiratelooksat50 at 06:12 AM on 19 January 2011
    Could global warming be caused by natural cycles?
    Muon @ 146 I know the difference between C and F. Apparently you failed to follow my link. I plainly referenced I was using the NOAA website and provided the link. It uses Imperial units. The website allows you to look at data from 1895 to 2010. I used their software to generate graphs and data pertaining to each decade by using the most recent 12-month period for rankings. Go check it out. "BTW, we 'came out of the LIA' decades ago, so you can stop repeating that. Besides, its a topic for another thread." I did not reference the LIA in that post. I referenced only the ice age, and it stands to reason the Earth warms coming out of a cold period. Are you going to answer about the temperature drop over the last decade? The decadal average is 0.12 F over that time period for a total rise of 1.26 F.
    Moderator Response: If you actually read the original post of this thread, you will see "the Milankovitch cycles that drive glaciation show that we should be, in fact, very slowly going into a new ice age (but anthropogenic warming is virtually certain to offset that influence)."
  25. Monckton Myth #3: Linear Warming
    NETDR i've tried to reproduce your data but i couldn't. I was able to reproduce only the same linear trend when using alog10 of concentration instead of the natural logarithm, but a different offset. Could you please give more details on what you did? By the way, using the correct logarithm I was able to reproduce Tamino's results (no surprise here); I can confirm that the coefficient of the quadratic term is statistically significant. Definitely CO2 is rising faster than exponential, let alone linearly.
  26. keithpickering at 05:23 AM on 19 January 2011
    Monckton Myth #2: Temperature records, trends and El Nino
    To be fair ... El Niño and La Niña are known to lead global temps by 6 months or so, which means that the 2010 temperature year should be most correctly compared to the SOI year of 7/2009 to 6/2010, which is fairly strong El Niño throughout. Using the same technique, one can also predict that early 2011 temps will be quite cool compared to recent years, as the current La Niña seems to be a doozy.
  27. Could global warming be caused by natural cycles?
    #152. if it is equally OK to say that it's a tie because of the la nina, it is equally OK to say that it's a tie because of the el nino. Actually it is more correct to say the latter due to the 3-6 months lack in response in global atmospheric temperatures to ENSO events and since the el nino was during fall-winter '09 through spring '10, whereas the la nina didn;t start until june/july '10 this delayed response caused '10 to be obviously mainly affected by the el nino and not the la nina. Please stop tap dancing to your own little drum and also accept facts that do not (always) support your thoughts and theories. Just because 2010 was a tie with 2005 and since it was an el nino year doesn't mean there is no AGW, it simply means that it was warmer because of an el nino (and AGW?). Just because there may be AGW doesn't mean global natural cycles have no influence on global temperatures anymore. They always have and always will. Please remember: no matter how beautiful the guess is, or how brilliant or famous the guesser is. If in the end the experiment shows the guess is wrong than that's all there is to it.
  28. Dikran Marsupial at 05:18 AM on 19 January 2011
    Monckton Myth #3: Linear Warming
    NETDR@26 The log of an exponential function is a linear function, regardless of what the "acceleration" is. Say we have an exponential function f(x) = A*exp{B*x} The second derivative (or acceleration is) f''(x) = A*B^2exp(B*x) Note the "acceleration" depends on the constants A and B. Now if we compute the log of f(x) we get g(x) = log(f(x)) = log{A} + B*x which is a linear function, whatever the values of A and B, and hence whatever the acceleration (which depends on A and B). I hope we agree so far. Now the radiative forcing due to CO2 is a logarithmic function of atmospheric concentration Forcing = C*log(f(x)) = C*log{A} + C*B*x This is also a linear function, but the slope depends on the rate constant of the exponential (B), but it also depends on the constant C which represents climate sensitivity. Thus whether the acceleration in the growth of CO2 is important depends on climate sensitivity, so you can't just dismis it without mentioning climate sensitivity. I appologise if making the argument in such basic mathematical terms appears condescending, but I couldn't think of any other way of demonstrating the flaw in your argument.
  29. Monckton Myth #3: Linear Warming
    Dana1981: "It's bad enough to cherrypick UAH, but even worse to cherrypick it over a timeframe during 25% of which it didn't even exist!" Speaking of cherry-picking UAH, I've noticed that over the same time period as the RSS, UAH trends significantly lower (though still upwards). I don't know why that is and it'd be presumptuous of me to speculate, but it seems to make UAH more attractive as a source for the obfuscation of temperature trends.
  30. Could global warming be caused by natural cycles?
    #155. Please see my previous comment (#151). The current la nina is NOT the strongest on record. Current SST anomalies are about the same (0.1C lower) than the 2008 La Nina which was the weakest "peak" la nina since 1975 and the lowest "peak" la nina since 1950. (unfortunately I can't past a pictures here, otherwise you'd see exactly what I mean, but I can refer to my another post to give you an idea: here; #13. Now, time will tell if the current la nina will get any or much stronger, though most indications don't point that way. Also, and as I pointed out previously, global temperatures LACK 3-6months behind in response to ENSO events. Hence, most of the atmosphere won't respond until right around now...
  31. actually thoughtful at 05:02 AM on 19 January 2011
    Could global warming be caused by natural cycles?
    Apirate, There isn't much I can do if you insist up is down and down is up. The null hypothesis is the one where you don't monkey with the system. Pumping in 6,000,000,000 tons annually of CO2 into a basically closed systems is a textbook example of monkeying with the system. Take a look at : http://www.skepticalscience.com/human-co2-smaller-than-natural-emissions.htm I admire those of you in a quixotic battle with reality, but I do think it requires being impervious to some important facts to maintain, for example, that it is PDO, or ENSO. Natural cycles are, by definition, cyclical. For natural variability to be in play, what went up must come down. Barring an external forcing (which our clever climate scientists tell us is CO2 - but you want to ignore that, which leaves us with NO forcing) - the longest cycle ever claimed is a 60 year cycle. If you start in 1950 you are toast (we are at 60 years - no cooling). If you start at 1980 - (and ignore lots and lots and lots and lots of counter-facts) - you have 30 years of non-stop cooling to get this cycle to come back to the 1980 start. Good luck. I don't mean to be rude but you have broken my system - it only works when you use facts and valid logic. You came back with a muddled logic, which is so confusing that you can't properly frame the topic - or even see how bad your initial conceptual frame is. I urge you to come up with another way of thinking about it - as your starting position is one that I (pessimistically perhaps) think you won't be able to think your way out of until the data is even more overwhelming. Here are some ideas for other approaches (if it helps, we can call the your first effort a draw, as I am at a loss as to how to throw you a logical life preserver - your concept is internally consistent, but doesn't allow you to recognize reality until a scientific proof is available). Recognizing, of course, that science doesn't have proofs. Science has theories. Theories that explain the world, and are considered "generally accepted" when there is no better theory available and the preponderance of evidence supports the theory. This is the case with climate science (sometimes called AGW). So here are some ideas and ways to think about it that should avoid the shoals of your flawed null hypothesis. 1. Why is warming more at night? 2. What evidence will convince you that AGW is correct? What will convince you it is false (bonus if you can get to your "final answer" within the decade). 3. Can you offer off a complete theory with an equivalent level of explanatory power (if you understand CO2 and greenhouse gases are causing the warming, you can explain coral reef bleaching, rising sea levels (and their rate), changes in weather patterns, loss of mass at arctic and Greenland ice sheets, loss of mass at the South Pole and on and on). If your mind takes you to the null hypothesis - fight the magnetic pull of that closed circle argument. Once you get back on that track you could find you have no escape (there is, but it requires getting out of that endless loop).
  32. The Physical Chemistry of Carbon Dioxide Absorption
    I have just discovered an excellent reference that clearly discusses clouds, interferences, etc. My contribution (GWPPT6) was meant to be a description of the effect of CO2 as a GHG that can be calculated without the use of a computer. As such it has significant limitations, in particular it does not deal with any of the important effects of interaction (e.g. between H2O and CO2) that are dealt with in the reference. The upshot of the reference is that the simple approach of GWPPT6 overestimates the GHG effect . That result is fine with me because it was my only purpose to describe the basic physics of the absorption. At any rate for those who wish a signifcantly more inclusive, but very clearly presented, description of the GHG effect I strongly recommend, G. A. Schmidt, et.al.,J. Geophys. Res.,Vol 115, D20106 (2110). In this paper the authors distinguish between a maximum, acting alone, effect (which is what is calculated in GWPPT6) and a minmum effect (upon removal of CO2, for example) where the effect in question is calculated with the inclusion of vater vapor and clouds. The result that relates to GWPPT6 is that the "Single Factor Removal", i.e. the effect as calculated with all interactions and then with all intereactions with CO2 removed, results in a decrease in the current GHG effect of 14.0%, while the "Single Factor Addition) (add in CO2 with but ignoring interactions) is 24.6%
  33. It's Pacific Decadal Oscillation
    Indeed; however, MEI is a ranking system not a value or measurement in it self, such as a SST for example. MEI looks at "all" effects of la ninas and el ninos, combines those and ranks the outcome: six main observed variables over the tropical Pacific, some of which not related or only indirectly related to temperature: e.g. sea-level pressure, zonal and meridional components of the surface wind, and total cloudiness fraction of the sky. ONI is a SST. In addition, MEI is bi-monthly, ONI tri-monthly. Hence the fact that some bi-monhtly MEI rankings are high doesn't necessarily mean it is also the coldest (lowest SST) la nina, which it obviously is not according to NOI. We indeed need to wait and see how the current la nina develops; in December SSTs crept up a bid, but have decreased again somewhat in January. The most recent pattern of SST anomalies is similar to that observed since mid November 2010. I'd expect the NDJ season somewhere between -1.3 and -1.6 at the most. Note that global temperatures lack often 3-6 months in response to ENSO events.
  34. actually thoughtful at 04:32 AM on 19 January 2011
    Could global warming be caused by natural cycles?
    Eric (skeptic) My information comes from NASA. "The solid record of La Nina strength only goes back about 50 years and this latest event appears to be one of the strongest ones over this time period," said climatologist Bill Patzert of NASA's Jet Propulsion Laboratory in California." The language was clear than I remember, so I can live with "one of the strongest". (the link is long, and my patience short - you can google the quote and see the story - it is not the data, but Bill Patzert's analysis.)
  35. Monckton Myth #3: Linear Warming
    NETDR, you're still doing the analysis wrong. You don't fit a curve to the log data. If the log data is linear then the growth is exponential. If the log data has grown faster than linearly (as is the case for the CO2 data), then the growth is faster than exponential. Tamino has already shown all of this. You're just doing the analysis wrong and thus arriving at the wrong conclusions.
  36. Monckton Myth #3: Linear Warming
    Dikran As is commonly accepted the log of the CO2 is proportional to the effect of the CO2. The log is increasing so slowly that the effect increases slowly too. Saying something is exponential is just hand waving if the exponential part is very low, which it is. Since the slope of the effect [log] is .0018 the increase is small. in 90 years the effect increases 16 %. The effect of the second derivative as shown above is negligible and is negative . [-5E-05x3 ]
  37. Monckton Myth #3: Linear Warming
    All, This is one of the fallacious statements made by Monckton: "CO2 concentration is rising in a straight line at just 2 ppmv/year at present and, even if it were to accelerate to an exponential rate of increase, the corresponding temperature increase would be expected to rise merely in a straight line." That first claim has been shown to be demonstrably false. The second claim is a "what if", but in the real world the appropriate mathematical and statistical treatment of the data (and appropriate nomenclature, as noted by Dikram @24) show that the we are already there. This really is a no brainer and it is disturbing that people are willing to go out on a limb and shred their own credibility by trying to defend Monckton's fallacies.
  38. Monckton Myth #2: Temperature records, trends and El Nino
    I have a question which I hope will not be considered too off-topic: In looking at the history of temperatures in the 20th century, we see a slowing of temperature rise which I guess goes roughly from 1940 through 1970 or so. In previous discussions I see that this is attributed to sulfate aerosols. OTOH the fact that the slowing occurred roughly starting in 1940 makes me wonder if WW2 had something to do with this. (This is just a historical side note to the larger discussion, I have no hidden agenda.) Thanks to anyone who cares to respond.
    Moderator Response: [Daniel Bailey] Welcome to Skeptical Science. You start off with an excellent question. I won't go into it, as it is off-topic here, but there's a couple of nice posts on that topic here and here. Please post any further questions and comments on that subject on the relevant thread. For other questions, the Search function, located in the upper left of every page here, is your friend.
  39. Could global warming be caused by natural cycles?
    NETDR @153, Feel free to quantitatively demonstrate that "The PDO is a natural cycle and I [and others on this thread] contend the warming from 1978 to 1998 can easily be explained by it." on the appropriate thread. IMHO, you would probably have better luck explaining more of the variance in the global SAT record using the AMO than the PDO. "From 1998 to present it s debatable whether there is any warming" Also on the wrong thread, and you seem to have been hoodwinked by Monckton et al's misinformation. Robert Way uses various datasets to dismisses that myth here. This will suffice for now:
  40. Dikran Marsupial at 02:43 AM on 19 January 2011
    Monckton Myth #3: Linear Warming
    @NETDR "So the rate of acceleration term is tiny." That is irrelevant; if the rise in CO2 is exponential (or faster) then the increase in radiative forcing will be (super-) linear, regardless of the acceleration. The log of an exponential is a linear function, it is a fact of mathematics that can't be circumvented by fitting polynomials. I think part of the problem is that there is a colloquial meaning of "exponential" used in hyperbolic statements about uncontrollable runaway growth. There is another mathematical definition. In this case, it is the latter that is relevant, but some are using the "hyperbolic" definition and hence are surprised that the deviation from a linear model is not that large. However, to the more mathematically inclined, that is no big surprise.
  41. Monckton Myth #3: Linear Warming
    I think the central problem in Monckton's claim of "log(exponential) = linear" has perhaps not quite been addressed here... The reason people think of our growth in emissions as roughly exponential is that really is the standard assumption of economics - a roughly constant growth rate from year to year. That translates into a close to exponential rise in CO2 emissions, assuming carbon intensity doesn't change (or changes itself at an exponential rate) with a doubling time of around 30 years (say 2%/year growth). But the *total* CO2 concentration in the atmosphere is a combination of the *pre-industrial* value (280 ppm) plus this exponentially growing anthropogenic piece - i.e. something like: CO2(year) = 270 ppm + 100 ppm * 2^((year - 2000)/30) In the long run, that expression is going to be dominated by the exponential term. But for the next 50 years or so it's a *SUM* of a flat term plus an exponential. And the logarithm of that is not something that rises linearly, but something that rises faster than linear (for now).
  42. Could global warming be caused by natural cycles?
    Moderator I totally disagree! The discussion about the PDO belongs on this thread. The name of this thread is "Could global warming be caused by natural cycles?" The PDO is a natural cycle and I [and others on this thread] contend the warming from 1978 to 1998 can easily be explained by it. The period 1978 to 1998 is the only period when there was unequivocal warming which has been linked to CO2 [incorrectly in my opinion] From 1998 to present it s debatable whether there is any warming. If so it is slight at best.
    Moderator Response: [Daniel Bailey] As you well know, having commented on the PDO thread several times (and been corrected several times there), in-depth discussions of various topics at Skeptical Science need to be placed on the appropriate threads. As you were counseled before, you maywill need to learn to use the Search function to do that. Discussions on PDO belong on the PDO thread already linked for you. As for the "no warming since 1998" meme (you are aware, aren't you, that 2005 and 2010 were both hotter than 1998?), removing the impact of natural cycles like ENSO and other things like volcanoes, explain this (from Open Mind):
  43. Monckton Myth #3: Linear Warming
    First of all I was incorrect the exponent is 2. [I saw it after I hit "submit"!] We don't need to assume a constant acceleration. The 3 rd order equation for a best fit is: y = -5E-05x3 + 0.0159x2 + 0.7345x + 312 So the rate of acceleration term is tiny. The sample is over 50 years so any acceleration should be evident. I am only looking at 90 years because we will have transferred to renewable fuel by then. Mark R said "You test for the acceleration in a standard way (trend in the residuals) and you find it. You test it against an exponential increase too and you find an acceleration there. " I like the third order polynomial better. I also took the log of the CO2 data and plotted it. The slope was .0018. The equation is: y = 0.0018x + 2.4878 Over a 90 year period the rate of increase in effect is almost negligible. You could do the increase in increase forever and the effect is negligible.
  44. Not a cite for Soare eyes
    Looking at the page for the International Journal of the Geosciences, it has an "open access" icon at the top, next to the name of the journal. International Journal of the Geosciences- Open Access Does this mean that anybody with the price of publication can now be a "peer reviewed" author? There appears to be another paper on climate science in Volume 1, Number 3 of IJGS "Recent Energy Balance of the Earth" by Knox and Douglass:
    A recently published estimate of Earth’s global warming trend is 0.63 ± 0.28 W/m2, as calculated from ocean heat content anomaly data spanning 1993-2008. This value is not representative of the recent (2003-2008) warming/cooling rate because of a “flattening” that occurred around 2001-2002. Using only 2003-2008 data from Argo floats, we find by four different algorithms that the recent trend ranges from –0.010 to –0.161 W/m2 with a typical error bar of ±0.2 W/m2. These results fail to support the existence of a frequently-cited large positive computed radiative imbalance.
    Gee, that's a surprise. Using a shorter interval obscures the trend? Who knew?
  45. Arkadiusz Semczyszak at 01:31 AM on 19 January 2011
    Global Warming and Cold Winters
    You can not ignore the opinions of this discussion, Professor Mike Lockwood: “There is no doubt that the frequency of those blocking events in winter is higher when solar activity is low,” says Lockwood. “What was a slight surprise is that the sun was changing the jet stream, but only when the jet stream has travelled across the Atlantic and begins hitting land over Europe.” At present in the Arctic - the Arctic Circle - half a year continues night. Large extra warmth can come only from the equatorial zone (system: NAO - AO - AMO - AMOC).
  46. Could global warming be caused by natural cycles?
    #151: "it is more correct to say that due to the past el nino we have a temperature tie" That seems like a lot of fancy tap dancing to explain what clearly stands on its own. "If the warming trend continues, as is expected, if greenhouse gases continue to increase, the 2010 record will not stand for long," said James Hansen, the director of GISS. Perhaps one should ask 'why was this el Nino so strong? why is the following la Nina also so strong?' Perhaps there is somewhat of a longer term mechanism driving those oscillations. But ask those questions on the appropriate thread.
  47. Hockey stick is broken
    Your second graph, LandyJim, I presume comes from Monckton, or someone similar ? The latest date on it would have to be 1994, I would imagine. How do you think it would look with the temperatures up to 2010 - whatever the temperature scale on that graph actually means and for which location. Do you know ? What do you believe you are trying to show with the Vostock graph - that temperature has varied in the past ? How does that relate to today ? There are more of these you can see here and here, if you like those sort of long-term measurements. As for the fourth one, it isn't from the Abrupt Climate Change paper as you stated; and neither is it from the The Younger Dryas cold interval as viewed from central Greenland" as suggested in your subsequent post. Well, I couldn't find it, anyway, after a quick look, although I did find the data. Perhaps you could point it out more exactly ? You can even see EPICA and VOSTOK compared here, if you would like.
  48. Did Global Warming stop in 1998, 1995, 2002, 2007, 2010?
    OK..on reflection comments about Vineyards are unhelpful and very misleading. I was remembering statements made in History of Roman Britain from School and as I am not really a wine drinker..I was not aware of the extend of modern British Vinyards. The Most Northerly I have found, which clearly blows my earlier comments well out of the water is this one.. Holmfirth Vineyard, Woodhouse Farm, Woodhouse Lane, Holmbridge, Holmfirth HD9 2QR This is surprisingly close to surviving sections of Hadrian's Wall and thus I think in future I will ignore Vinyards and Hadrian's wall comments... Apologies for that.
  49. Monckton Myth #3: Linear Warming
    Perhaps this would be worth a short post? You can estimate final CO2 from current trends, assuming we continue as usual. First I tested to see whether quadratic was a good fit. It's ok: you can test for acceleration by assuming C=At^2 where C is carbon, t time and A constant. Rearrange to get C^(1/2)=At. Not plot the two together and if the risiduals (difference between a straight line and the actual results) are not random then you have some kind of acceleration. In this case there is an acceleration and it's positive: we are increasing faster than with the square of time. We can use this to put a MINIMUM on the amount of CO2 we expect by 2100 assuming we continue on as Mauna Loa data says we have for the past 50 years or so. Take the annual differences in CO2 and then plot them against year then fit a line: the trend is the acceleration in change of CO2 per year per year. It is 0.026 +/- 0.04. You can assume a constant acceleration (i.e a quadratic) which we know is a MINIMUM for the CO2 changes we expect. Then you can use a SUVAT to determine final CO2: s = ut + (1/2)at^2 Where u is the current rate of increase of CO2, about 2ppm/yr averaged from 2001-10. a is the acceleration, or the 0.026 we just worked out. Therefore final s, or CO2 concentration in 90 years time at 2100 is just over 680 ppmv. (This is LOWER than the actual better fit) So we expect an additional minimum of 3 W m^-2 of CO2 radiative forcing in the next 90 years from the Mauna Loa data. On top of the ~1.8 W m^-2 from the past 160 years. Obviously an acceleration if you bother to look at the Mauna Loa data. Which Monckton doesn't. His analysis is simply wrong too: exp * ln is only linear in special cases. I did this in a rush literally on the back of an envelope and excel. Off to lunch, but I'll check it later. Please correct me if I got it wrong!
  50. Monckton Myth #3: Linear Warming
    You don't need anything other than a simple spreadsheet to check the Mauna Loa data. Check the residuals from the linear fit: if they're random then there's no acceleration. They're not, so there is. You can plot the data logarithmically like Tamino did (I did it for annual, rather than 10-yr means). And the annual data residuals show acceleration above exponential! (although we should be careful with individual periods - 1990 saw the USSR collapse for example) You test for the acceleration in a standard way (trend in the residuals) and you find it. You test it against an exponential increase too and you find an acceleration there.

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