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Tom Curtis at 22:15 PM on 10 June 2013CO2 effect is saturated
Elsewhere, SASM asked some questions that were snipped for being off topic. They are on topic here, so I will address them. He says:
"Is it true that CO2 is nearly fully saturated in the IR bands? I have read (http://www.skepticalscience.com/saturated-co2-effect.htm) and it clearly shows that CO2 is dimming some IR to space in the 700 to 760 wavenumber bands, which is mid-wave IR around 13-14 um. Brightness is reduced by about 1.5K, but what is this in watts/m^2 or how much warming does this blockage produce? My speculation is that this is not very much. WUWT has a post (http://wattsupwiththat.com/2013/06/08/by-the-numbers-having-the-courage-to-do-nothing/#more-87809) that states that 94.9% of the IR is absorbed by 400 ppm CO2. The increase from 300 ppm to 400 ppm (the amount from early 1900 until now) only blocks 2.3% more than what is naturally occurring (i.e., 92.6% absorption for 300 ppm CO2). Do you all agree with these numbers, and if not what numbers do you have? How much additional warming is directly caused by the increase from 280 ppm to 400 ppm today? Don’t include forcing, feedback, or anything like that – just effects of CO2"
Turning to the WUWT post, it is complete nonsense. It does not indicate how the values of any of its tables were determined, and makes absurd false statements such at that at least 200 ppmv is required in the atmosphere for plant life to grow (CO2 concentrations dropped to 182.2 ppmv at the Last Glacial Maximum, giving the lie to that common claim).
More importantly, the claim that the "...proportional values shown above present are universally accepted by skeptics and Global Warming alarmists alike..." (PDF) is complete bunk. They are not accepted universally by AGW "skeptics" and are accepted by no defenders of climate science. Specifically, the "universally accepted" formula for radiative forcing is RFt = 5.35* ln(ct/c0). That is, the radiative forcing due to CO2 at time, t, relative to time, 0, equals 5.35 times the natural log of the CO2 concentration at time t divided by the CO2 concentration at time 0. The equilibrium temperatue response to that radiative forcing is a linear function of the radiative forcing, so that it follows the same logarithmic relationship.
An immediate consequence of that logarithmic relationship is that the temperature response for a doubling of CO2 concentration is the same for any doubling of CO2 concentration across the range over which that formula is valid (it clearly does not apply for very low values of CO2). That is, if the temperature response for increasing CO2 from 100 to 200 ppmv is X, then the temperature response for increasing it from 200 to 400, or 300 to 600, or 400 to 800, or 500 to 1000 ppmv will also be x.
Contrary to that relationship, however, Hoskins shows the increase from 100 to 200 as being 10.1% of some unknown value; that from 200 to 400 as being 7.3% of the same value; that from 300 to 600 as being 5.2%; that from 400 to 800 as being 4.6%, and that from 500 to 1000 as being 2.1% (PDF). As such his tables contradict the best known, and most widely accepted formula in climate science. Even worse, he then goes on to say that "beyond 1000+ ppmv the effect of increasing levels of CO2 can only ever be
absolutely minimal even if CO2 concentrations were to increase indefinitely." (PDF) That claim is the basis of setting the temperature response to 1000 ppmv as 100%, but is complete bunk. As per the standard formula, the temperature response of an increase in CO2 level from 1000 to 2000 ppmv is the same as the the temperature response for an increase from 100 to 200 ppmv.Hoskins does not even apply his formula consistently. Based on his first table, the increase in temperature for a given increase in CO2 concentration expressed as a ratio of earlier increases should be constant regardless of whether you use IPCC values, or "skeptical" values. Yet in his second table (WUWT post) that condition is not met. In other words, his calculated temperature responses in his second table are inconsistent with those in his first table.
Anyway, with the standard IPCC climate sensitivity of 3 C per doubling of CO2, increasing CO2 from 400 to 1000 ppmv will increase temperature by 3.9 C. That will represent a 5.4 C increase over pre-industrial levels - an increase equivalent to the difference in temperature between the coldest period of the last glacial and the pre-industrial.
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ajki at 20:49 PM on 10 June 20132013 SkS Weekly Digest #23
Wow, this is a magazine that did understand this "sustainability" thing right by reusing its own covers :-D
May I use the opportunitiy to point the SkS team to one journalist who really tries hard to promote the many difficult issues around global warming and especially the arctic regions: Irene Quaile with her blog "Ice Blog" on dw.de (Deutsche Welle, a state owned broadcast). Throughout the years I've really learned to love her coverage and the great photo material on her blog.
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Paul Pukite at 14:43 PM on 10 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
I commented at #4 with a double-check on Lu's regression analysis. Lu claims he did an analysis where he removed the effects of the solar component. What is interesting is I used his correlation recipe but only sliding by a lag of 9 years and got the same R^2 as he got.
I think this has important implications because his correlation coefficient didn't improve by removing the solar component. This could only happen if it was just a random effect in the first place. IOW, he didn't do a null test, but simply claimed that the solar improved the fit.
I might be missing something, that is why it is nice to have the SkS blog available.
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Paul Pukite at 14:38 PM on 10 June 2013New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made
Using the equatorial SST data for latitudes -6±15 degrees, we can take the Mauna Loa CO2 data and compensate for seasonal outgassing. This has a Henry's Law gain factor of 3 PPM/deg C after applying a lag of 1 month. This simple transformation completely removes the seasonal oscillations, leaving only low-level noise and perhaps a few glitches related to El Nino events (see 1998-1999).
The above figure is the compensated Mauna Loa CO2 data after removing the seasonal IPWP ocean outgassing of CO2. I also placed a polynomial fit as a guid to the eye.
The above figure shows the Indo-Pacific Warm Pool (IPWP) lies within the +9N to -21S SST average. This is the hottest part of the Pacific and should have the strongest activation for CO2 outgassing.
The SST data was taken from a NOMADS server (NOAA Operational Model Archive and Distribution System)
http://nomad3.ncep.noaa.gov/cgi-bin/pdisp_sst.sh?ctlfile=monoiv2.ctl&varlist=on&psfile=on&new_window=on&ptype=ts&dir=The CO2 data was taken from the Mauna Loa records, going back to 1981 to match the archival extent of the SST records
http://www.woodfortrees.org/data/esrl-co2/from:1981I have to say that the available oceanographic and atmospheric data is an amazing resource for debunking claims made by people like Humlum (and don't forget Murry Salby).
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EliRabett at 12:58 PM on 10 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Chordotonal, the good Professor Lu did not fit a curve, he tortured the poor dear with thick lines until it cried enough. The level of curve fitting was "look at that" without any statistical analysis. Follow the link
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Tom Dayton at 11:59 AM on 10 June 2013CO2 effect is saturated
Stealth, see also "A Saturated Gassy Argument" part 1 and part 2. For more technical depth, check out Science of Doom; there are several places where saturation is discussed, but you might start with Part Five.
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scaddenp at 10:45 AM on 10 June 2013Imbers et al. Test Human-Caused Global Warming Detection
And please move further comments to the appropriate thread. Regulars view this site through "comments" link so you comment doesnt get lost. Offtopic comments will be deleted.
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scaddenp at 10:43 AM on 10 June 2013Imbers et al. Test Human-Caused Global Warming Detection
Stealth, you can play with the numbers yourself with this wonderful calculator. The mathematical introduction in Ramanathan Coakley 1978. Doubling CO2 from 280 adds 3.7W/m2 from CO2 alone.
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StealthAircraftSoftwareModeler at 10:13 AM on 10 June 2013Imbers et al. Test Human-Caused Global Warming Detection
DSL @43. It seems my comment may have been deleted and I am not sure why. I did ask some questions and you seemed to answer one of them, so it was posted for some time. Perhaps the moderator thought my post was an ad hominem or not on topic or inflammatory. If so, I apologize. I’m not looking to start any flame wars and I am honestly looking for a good discussion.
Let me just completely back up and ask some basic questions:
(-snip-). Thanks! Stealth
Moderator Response:[DB] Your previous comment was moderated out as it contained multiple off topic statements, as does this one. Please take your individual concerns and questions to the most appropriate threads and place them there. The regulars providing dialogue interaction and guidance here will see them, no matter where you place your questions, and will respond as appropriate on those same threads.
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Esop at 09:26 AM on 10 June 2013New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made
This paper from Humlum and similarly nonsensical stuff from the likes of Salby reminds me of the Simpsons episode where Bart is the "I didn't do it" boy. A juvenile display of not being capable of taking any responsibility for own actions. What is next from Humlum and his Norwegian cohorts ? A new paper claiming that humans don't actually emit CO2 at all?
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P.T. Goodman at 09:26 AM on 10 June 20132013 Arctic Sea Ice Extent Prediction
I found out more than I needed to know about Steve Goddard when he infested a Washington Post Op-Ed called Climate science tells us the alarm bells are ringing by posting 500 comments out of less then 5000 this weekend. Truth be told, I lost count of his comments last night at about 200 but he has been hard at it all day today. Sadly, the Washington Post blogs has very loose moderation standards, so anyone can get away this this stuff. It just makes it impossble to have a real discussion about climate change, but I suppose that is Goddard's goal. They just don't want others talking about climate change.
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SeaHuck5891 at 01:09 AM on 10 June 20132013 SkS Weekly Digest #22
@ Tom Curtis
Thank you for the response.
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Tom Curtis at 00:23 AM on 10 June 20132013 SkS Weekly Digest #22
SeaHuck5891 @2, if all CO2 emissions were to cease tomorrow, the atmospheric concentration of CO2 would gradually decline to about 340 ppmv over a couple of centuries or so as the partial pressure of CO2 equalized between the deep ocean and the upper reaches of the ocean. (That ignores, or course, the production of CO2 by the oxidation of methane; but it is a reasonable approximation.) Based on this, if we were to reduce emissions to the equivalent of 0.3 ppmv per annum, ie, about 6% of current emissions we would stabilize CO2 concentration rather than gradually reduce it. Anything more than that would result in a continuing increase in atmospheric concentration.
It should be noted that, first, the 6% figure is a ball park figure only; and second, that there are very good policy reasons to prefer the draw down in CO2 to the constant concentration. Consequently I consider that figure to be largely academic.
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SeaHuck5891 at 23:38 PM on 9 June 20132013 SkS Weekly Digest #22
I had a conversation about climate change with a friend recently, and the topic of CO2 drawdown came up. My explanation was that roughly 50% of the CO2 emitted by humans is absorbed by natural carbon sinks, thus leaving the remainder in the atmosphere as the "airborn fraction". My confusion started setting in when asked at what level of anthropogenic CO2 emissions can we expect to see no further accumulation in the atmosphere. Is there a level of human emissions that will allow us to cease the upward trend in the Keeling curve? Is it as simple as saying that cutting our emissions in half will suffice? And if the answer to that question is yes, does it follow that any level of emissions below that point will allow for (very, very) gradual drawdown? If there is an appropiate thread for this discussion, I will gladly take it there, but a quick search did not show any results.
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John Hartz at 23:09 PM on 9 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Geencooling's concerns about the role of HFCs in climate change are shared by the Chinese and US governments as documented in Andrew Revkin's DoT Earth post of yesterday (June 8).
As some environmental analysts had hoped, President Obama and President Xi Jinping of China found room to maneuver on global warming in their California desert retreat. They sidestepped the super wicked issues impeding restrictions of the greenhouse gas of greatest concern, carbon dioxide, and staff released a joint statement on plans to cut releases of hydrofluorocarbons, or HFCs, a potent group of heat-trapping gases.
Source: With CO2 Cuts Tough, U.S. and China Pledge a Push on Another Greenhouse Gas by Andrew Revkin, DoT Earth, New York Times, June 8, 2013
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michael sweet at 12:37 PM on 9 June 2013Renewables can't provide baseload power
The San Onofre nuclear power plant in Los Angeles is being permanently closed. They were intending to expand generation capacity and installed a badly engineered heat exchanger. They have decided that it is too expensive to fix. Florida still has a broken plant we are paying for. The utility makes 10% on everything they spend on the plant, even if it never generates more electricity.
If it is uneconomic to repair an existing plant, how could it be economic to build a new plant?
Wind and solar keep looking better and better.
Moderators: I couldn't find a better thread for this post. If you suggest one I will repost and this one can be deleted.
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GreenCooling at 11:23 AM on 9 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Many thanks Dana for correcting the reference to hydrofluorocarbons in the second para just now, but as mentioned in my tweet, it is radiative forcing that has remained roughly stable, the emissions picture is rather more complex. As I've said on the "It's CFCs" thread, and over at Eli's Rabett Run blog, the rapidly rising emissions of HCFCs and particularly HFCs are deserving of more attention in the climate change policy debate.
If anything useful comes from the publication of Lu's discredited theories about CFCs, I hope it's a greater recognition that by phasing out the very high GWP ozone depleting CFCs, the Montreal Protocol has done 5 times as much as the first committment period of Kyoto to reduce radiative forcing emissions. Because the CFCs have very long atmospheric lifetimes (and emissions from 'banks' are larger than projected and lamentably very little is yet being done to prevent them), the halocarbon 'stock' is not declining very much yet, although the 'flow' has been radically reduced.
Alarmingly, the climate benefits acheived by the Montreal Protocol are now threatened by rapidly rising emissions of HFCs used as substitutes for Ozone Depleting Substances, which are increasing at around 9% p.a. (and HCFCs, which although being phased out are still increasing by around 4.3% p.a.). Using the Montreal Protocol to phase out the HFCs is entirely possible with available natural refrigerant solutions (and arguably emerging expensive and less efficient patented synthetic alternatives, for those concerned with protecting the profit margins of the chemical companies responsible for the F-Gas problem). Worthy amendment proposals to achieve a less ambitious "phase down" are up for discussion for the 5th year in a row in Bangkok later this month, and again in November at the Meeting of the Parties. While the EU (and Australia) at the UNFCCC talks are urging the Montreal Protocol to act on these, you need to look hard to find coverage of these proposals.
In both the ABC radio AM piece cited above, and the ABC Science article "CFC Warming Theory Challenged" the climate impact and significance of CFCs, HCFCs and HFCs is not clearly explained and understated. I'm concerned these articles, and the much warranted rebuttals of Lu's paper are contributing to the mistaken notion that the halocarbon problem is fixed.
Extending the Montreal Protocol (and implementing end use bans and carbon pricing mechanisms) to control and reduce use and emissions of HFCs are among the most fast acting and cost effective tools at our disposal for reducing emissions and preserving the significant climate benefits of the Montreal Protocol, yet this remains a complete surprise to most people, even those highly engaged in the climate debate.
Moderator Response:[JH] Would you be willing to expand your excellent comment into a guest article?
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Tom Dayton at 06:43 AM on 9 June 2013Satellites show no warming in the troposphere
Roy Spencer's latest claim that the tropospheric temperature proves the models wrong, has been aptly shot full of holes by Glenn Tamblyn and others. For example, Spencer compared temperature observations from only the tropics, to model results between 20 and 20 latitudes. Spencer compared model results for the surface, to observations of the "middle troposphere." Spencer's observations of the "middle troposphere" actually are 1/4 from the stratosphere, which of course cools as a consequence of increased greenhouse gases.
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Tom Dayton at 06:31 AM on 9 June 2013Lindzen's Junk Science
The site What's Up With That Watts? has a point by point dissection of a 2009 lecture by Richard Lindzen: Part 1, Part 2, Part 3.
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william5331 at 06:27 AM on 9 June 20132013 SkS News Bulletin #15: Alberta Tar Sands and Keystone XL Pipeline
You have to ask yourself why is Canada shipping raw, crude to the US of A. Why don't the refine it into petrol, diesel etc and get the value-added from their product. Not only is the Harper government an ecological disaster, they are economically dumb. You would expect a right wing government to at least have some economic smarts. I wonder how much revenue Canada is actually getting from this whole sorry mess in comparison with how much American companies are making. At least they are in line with former Canadian governments. Read Farley Mowat's book Sea of Slaughter to see how former governments have treated Canadian resources. The only reason Canada is green is that she has so much land with so few people. Until she gets rid of "first past the post" nothing will change.
A Canadian abroad.
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Alexandre at 02:28 AM on 9 June 2013Scientists use crowd-sourcing to help map global CO2 emissions
I tried to include one from Brazil, (-3,6808037378312144, -38,86519119143486) but it keeps saying "invalid coordinates" or something to that effect.
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dana1981 at 00:51 AM on 9 June 2013Meet the world's best new environment bloggers
Thanks dorlomin.
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MA Rodger at 00:29 AM on 9 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
By way of illustration for the comment @147. ( I assume the graph is visible to all.)
The "minor negative trend" actually is the " the recent slowing of the (global) warming rates" which remain entirely unattributed after the MLR analysis. (Contrary to my comment @147, it would of course subtract from the rate of anything it was attributed to.)
And bar minor excurtions, for just over half the record the HadCRUT4 signal survives unattributed at 50% amplitude. Can this be right?
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dorlomin at 20:00 PM on 8 June 2013Meet the world's best new environment bloggers
Been reading your stuff on the Guardian and really happy to see it.
Chapeau.
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MA Rodger at 19:17 PM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
KK Tung @137
While the discussion is considering appropriate trends, perhaps it is timely to extend the discussion to the identified trend that T&Zh13 failed to attribute. The Residuals from assuming the QCO2(t) function are shown inset in Figure 3 in Part One of this post where they are described thus:- "Except for s a minor negative trend in the last decade in the Residual, it is almost just noise."
I had wondered if this "minor negative trend" was the " the recent slowing of the (global) warming rates." In T&Zh13 this "slowing" is described as being "included" the "superimposed AMO-related ups and downs," yet the trend within the Residuals suggested to me that perhaps not all this "slowing" had actually been "included." Certainly AMO as per Enfield shows no "slowing" relative to HadCRUT4 that would compensate for the QCO2(t) function (ie the proposed anthropogenic warming contirbution) and this fuelled my curiosity, and prompted my question on this @112 above.Looking myself at those Residuals, the "minor negative trend" extends back further than "the last decade," indeed extending back beyond two decades. And is it "minor"when it has a trend of something like 0.6ºC/century? If such a level of trend were added to the trend in the QCO2(t) function, present-day attributable anthropogenic warming would then be running at 1.7ºC/century, pretty much the same answer that Foster and Rahmstorf (2011) arrived at.
So I suggest the "minor negative trend" is not "minor."
I would also add that it is also wrong (strong word) to describe the rest of these Residuals as "almost just noise." Closer examination shows otherwise. -
Dikran Marsupial at 18:35 PM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
KK Tung wrote "Many on this thread worried that some nonlinear part of the trend may still remain in the AMO index thus defined."
Not "may" but "will"; this is self-evident, linear detrending cannot possibly remove a non-linear component of the trend as it is a linear method. Over a short period, a linear trend may be a reasonable approximation to the sum of all anthropogenic and natural forcings (c.f. Taylor series expansion), but on the scale of a century this is clearly not a reasonable assumption.Do you accept that the AMO signal will remain contaminated by any non-linear component of the forcing? If "no", please explain how linear detrending can completely remove the effects of a non-linear contamination.
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Kevin C at 17:27 PM on 8 June 2013Imbers et al. Test Human-Caused Global Warming Detection
Mal Adapted: That's a great article, thanks for pointing it out. I've suggested to the powers that be that it might be worth a post.
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Eyal Morag at 15:34 PM on 8 June 2013New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made
Real Climate - On Humlum et al.
Humlum find a connection between ENSO and CO2 But don't understand his findings. C. D. Keeling and R. Revelle find and understand this connection at 1985.
El Nino’s effect on CO2 causes confusion about CO2′s role for climate change
Rasmus E. Benestad - Real Climate 11 September 2012
Anyway the same level of logic can find that temp don't connect to CO2 since every year from October to January the CO2 is rising while temp is falling. Just ignore the 1st & 2nd order of CO2 and temp rising.
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DSL at 13:58 PM on 8 June 2013Imbers et al. Test Human-Caused Global Warming Detection
As far as the CO2 part of the equation goes, I would need to see robust evidence for the proposition that atmospheric CO2 did not absorb/emit at various pressure-broadened bands in the thermal infrared range. Or I would need to see robust evidence that atmospheric CO2 is not actually present in observed concentration.
The only other forcing that can match CO2's persistent (non-condensing, well-mixed, long residence time) forcing is solar variation. I would need to see evidence that falsifies every major assessment of solar contribution of the past two decades (add Pasini et al. 2012, Jones et al. 2013, and Mann et al. 2013).
There can be evidence. There's always the possibility that aliens are manipulating instrumentation. Climate science is one of the most scrutinized sciences. All someone has to do to get a Nobel is falsify a major element of the current mainstream theory of climate, and do it in such a way that removes human responsibility. People have been trying for decades.
I think your characterization of climate science is a little off, as well. The current science lays the foundation for the discoveries of tomorrow, unlike the practice of blood-letting and modern medical practice. Your assertion strongly suggests that current climate science is utterly wrong. Where's the evidence for such an assertion? You talk of clouds and sun, and everything you know about them is blood-letting. Were the Wright brothers blood-letters, or were they useful pioneers? -
Tom Curtis at 11:40 AM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
KK Tung @144 says:
"The N. Atlantic mean SST trend is smaller than the global SST trend, and so this subtraction takes out too much. So right there we know there is an error."
I would be fascinated to hear how, a priori, KK Tung knows that absent any change of forcing over the twentieth century the North Atlantic SST would have had a neutral or positive trend. Absent that a priori knowledge, he cannot know that subtracting global SST from North Atlantic SST to determine the AMO is a mistake, or at least not on the grounds he states (ie, the difference in trends). KK Tung may think the absence of forcing guaranttees the absense of trend; but given an unforced oscillation in SST, a trend can be produced by differences in phase over the period of the trend. More importantly, as the AMO is avowedly irregular both as to period and amplituded, such irregularity can produce a trend even the period of the trend is in phase. It appears to me, therefore, that his claimed "error" amounts to no more than a circular appeal to the Enfield's definition, which gives him his "knowledge" of the phase, period and amplitude on which basis he dismisses the Trenberth definition.
Turning to the Enfield definition, the one thing we do know for sure about the AMO is that the Enfield definition is ad hoc. Specifically, different defined lengths over which the linear trend is taken will generate different strengths of the AMO at different times. If we take the period 1880-2010 ad defining the linear trend, for example, all periods prior to 1850 will have a strong positive AMO phase. Because it is ad hoc, we know the Enfield definition is in error. It may, however, be useful over a limited period. That it is more usefull than the Trenberth definition over any period, however, is something that is yet to be shown.
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KK Tung at 10:30 AM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
In reply to Robert Way at post 139: I agree with you. Not knowing what the true AMO is, all these definitions of the AMO index are ad hoc. Enfield's definition of the AMO index involves linear detrending of the N. Atlantic sea surface temperature (SST). Many on this thread worried that some nonlinear part of the trend may still remain in the AMO index thus defined. Many felt strongly that the Trenberth and Shea definition of the AMO index should be used. This index is the N. Atlantic mean SST minus the global mean SST. The assumption of those who thought this definition is more appropriate is that this way the nonlinear anthropogenic trend can be removed. I discussed this issue in part 2 of my post: The N. Atlantic mean SST trend is smaller than the global SST trend, and so this subtraction takes out too much. So right there we know there is an error. Technically the presence of a trend in the regression index also creates a problem of collinearity. An approach that we have taken is to use different methods and hope that the results are consistent. The wavelet method may have its own problems, but these problems are orthogonal to the problem of the MLR as no detrending is involved. Alternatively, we could do the MLR using different definitions of the AMO index. As Robert Way put it, we know that there could be some possible defect with any ad hoc definition we can come up with, but hopefully the true answer may lie in between. Even better if the error bars are small. I will give you a summary of this sensitivity calculation soon.
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KK Tung at 08:54 AM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
In reply to KR at post 140 and 142: I did report the result of MLR using Trenberth and Shea's AMO index. The 50-year anthropogenic trend is 0.1 C per decade. There was a problem with collinearity because that index has a negative trend, and I discussed why it has such a negative trend. I will try to put these sensitivity calculations together, along with a discussion of Ting et al 2009 paper, in a separate post.
I had replied to your question on the Anderson et al paper. As far as I am concerned that issue was settled.
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Mal Adapted at 07:40 AM on 8 June 2013Imbers et al. Test Human-Caused Global Warming Detection
John Nielson-Gammon gave a talk at last year's AGU meeting on Scientific Meta-Literacy. His key point:
But there’s an important lesson here about how we decide which scientific statements to believe and which ones not to believe. Those of us who are trained scientists but who do not have enough personal literacy to independently evaluate a particular statement do not throw up our hands in despair. Instead, we evaluate the source and the context.
We scientists rely upon a hierarchy of reliability. We know that a talking head is less reliable than a press release. We know that a press release is less reliable than a paper. We know that an ordinary peer-reviewed paper is less reliable than a review article. And so on, all the way up to a National Academy report. If we’re equipped with knowledge of this hierarchy of reliability, we can generally do a good job navigating through an unfamiliar field, even if we have very little prior technical knowledge in that field.
Well, the typical member of the public has very little retained technical knowledge about just about everything. I claim that it’s an impossible task to raise the level of climate literacy in the general public to the point where most can tell that the statement about the ice age is wrong, let alone whether the statement about Sandy is wrong. And what about all the other fields in which they need to be literate as well?
The solution to this problem is not scientific literacy, but what I call scientific meta-literacy. Forget that dream about enabling the public to independently evaluate scientific claims on their merits – that’s just not going to happen. Instead, enable the public to distinguish between reliable and unreliable sources of scientific information.
Skepticism is all very well, but it's important to understand that it takes work to become an expert, and if you're not willing to do the work, you have little choice but to trust the ones who have. A genuine skeptic recognizes and respects expertise. Otherwise, he risks falling prey to the Dunning-Kruger effect.
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william5331 at 06:10 AM on 8 June 2013New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made
"Humlum had just disproved the conservation of mass" Who says scientists don't have a sense of humor. Priceless.
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KR at 05:54 AM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
Dr. Tung - My apologies, I linked to entirely the wrong paper in this comment: I meant to refer to the Ting et al 2009 discussion on PCA separation of internal variability and anthropogenic contributions.
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Bob Loblaw at 05:29 AM on 8 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
The stratospheric cooling associated with increasing greenhouse gases is not a new idea. It shows up in 1-D radiative-convective modeling work in the 1960s. Two such early studies are:
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John Hartz at 05:29 AM on 8 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Chordotonal has recused himself from positng on SkS.
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Tom Dayton at 05:27 AM on 8 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Chordontonal, you seem to be unaware of... well, the entirety of climatology. So you consistently have made comments that are entirely off base (e.g., wrong, not even wrong), as you try to apply your general knowledge of science and philosophy. I suggest you start by learning the history of the science behind our knowledge of global warming. Then learn more about the fundamental physics of the greenhouse gas effect--physics that are known from actual experiments in the lab and observations in the field. Physics knowledge that was established without any thought to humans increasing global warming.
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John Hartz at 05:21 AM on 8 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Chordotonal:
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Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter, as no further warnings shall be given.
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John Hartz at 05:16 AM on 8 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Chordotonal:
Please note that posting comments here at SkS is a privilege, not a right. This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.
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Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.
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Dikran Marsupial at 04:53 AM on 8 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
chordotonal, "sloganeering" is clearly defined in the comments policy. Please read them.
I for one am not going to bother responding to your posts while you continue to use phrases such as
"That is a real bread and butter concept of science that is being attacked in service of what amounts to religious belief."
If you want to discuss the science, that is fine, but drop the rhetoric, nobody here is interested.Moderator Response:[JH] Chordotonal's subsequent post was sloganeering and was therefore deleted.
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DSL at 04:43 AM on 8 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Again, you build a strawman in the form of an alleged attack by SkS posters on correlation in general. No. If you're going to claim correlation = causation, as Lu did, you'd better damned well start talking about the physical mechanism in a methodologically sound way. Lu's method was unsound.
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Dikran Marsupial at 04:42 AM on 8 June 2013New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made
Bob Loblaw - very apposite, unlike my favourite maths joke:
Q. Why did the mathematician call his dog Cauchy?
A. Because he left a residue at every pole!
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Bob Loblaw at 04:35 AM on 8 June 2013New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made
With all this discussion of the problems caused by Humlum et al's analysis that differentiates the data first, I am reminded of a math joke told to me years ago by a mathematician friend. (Yes, I know. "math joke" is an oxymoron. Don't ask me to tell you the one about Noah and the snakes.)
Two mathematicians are in a bar, arguing about the general math knowledge of the masses. They end up deciding to settle the issue by seeing if the waitress can answer a math question. While mathematician A is in the bathroom, mathematician B corners the waitress and tells her that when his friend asks her a question, she should answer "one half X squared". A little later, when the waitress returns to the table, A asks her "what is the integral of X?". She answers as instructed, and mathematician A sheepishly pays off the bet and admits that B was right. As the waitress walks away, she is heard to mutter "pair of idiots. It's one-half X squared, plus a constant".
[I'm not sure how much of the joke is a dig at mathematicians who forget some of the basics (the constant), or a dig that mathematicians can only find jobs working as a waitress in a bar.]
But, back to the issue at hand - differentiation will take any constant term and turn it into zero. But to take the flux data and turn in back into a change in storage you have to integrate. And when you integrate, you are in deep, deep trouble if you forget the constant, which is what Humlum et al appear to have done. If you can't figure out what the constant is, then you can't figure out the numerical value of the integration.
Details. Details.
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John Hartz at 04:25 AM on 8 June 2013Lu Blames Global Warming on CFCs (Curve Fitting Correlations)
Chordotonal: You most recent post was sloganeering and was therefore deleted. Please read the Comments Policy and adhere to it.
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Dikran Marsupial at 04:11 AM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
KR testing the sensitivity of the analysis to the choice of AMO definition would indeed be a good thing, however they would all be susceptible to the problem of contamination with anthropogenic and natural forcings, and hence the resulting attribution will still be at best questionable.
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KR at 03:45 AM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
robert way - While there are many ways to calculate the AMO, I would disagree about Anderson et al 2012 being ad hoc; they are using PCA to estimate the anthro versus natural variation components; they have numeric support for their position. And they agree with the Trenberth and Shea 2006 method.
Regardless - Any comparison of Dr. Tungs technique against different AMO estimations would provide a sensitivity analysis for those variations in AMO definition. Dr. Tung has not performed such a check - and until/unless he does, I do not feel his conclusions stand given the various counterexamples of colinearity contamination discussed on these threads.
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Micawber at 02:59 AM on 8 June 2013New study by Skeptical Science author finds 100% of atmospheric CO2 rise is man-made
I thought the BEST group of physicists had proved once and for all that all global warming in last 250 years can be accounted for by volcanism and the log of CO2 concentration.
Rohde, R., Muller, R. A., Jacobsen, R., Muller, E., Perlmutter, S., Rosenfeld, A., Wurtele, J., Groom, D. and Wickham, C.: A new estimate of the average earth surface land temperature spanning 1753 to 2011, Geoinfor Geostat: An Overview, 1, 1, 7pp, doi: 10.4172/gigs.1000101, 2012.
This is consistent with the physics. The greenhouse gas is active in the upper stratosphere/troposphere boundary. To solar radiation Earth looks like a bubble. This bubble traps the heat. It is dependent on CO2 rather than water vapour that does not reach so high. Rohde et al., (2012) is consistent with this and explains all the temperature changes observed. What goes on inside the bubble affects that surface. Most of the surface is saltwater.
There is s similar boundary layer in the upper ocean that traps heat. According to Levitus et al., (2012) ocean heat accounts for 93% of anthropogenic global warming.
Levitus, S., Antonov, J. I., Boyer, T. P., Baranova, O. K., Garcia, H. E., Locarnini, R. A., Mishonov, A. V., Reagan, J. R., Seidov, D., Yarosh, E. S. and Zweng, M. M.: World ocean heat content and thermostatic sea level change (0–2000 m), 1955–2010, Geophys. Res. Lett, 39, L10603, 5pp, doi: 10.1029/2012GL051106, 2012.
Data from oceans is sparse at best with 1 degree lat and long coverage averaged over upper 100m only available since 1990s. What is needed is far better data on the 93% heat and rather less statistics on the 7%.
Unfortunately this requires going to sea and making actual measurements. It is timeseries of near-surface temperature and salinity data that holds the key. These are not available from satellites. Computer models are only as good as the field verification data. There are huge tracts of ocean for which data is lacking including the Pacific and the Arctic.
In my opinion it is time for a concerted effort to go to sea and get the data. It can only confirm what Rohde et al., (2012) showed - CO2 concentration is the principal driver of global warming; and confirm Levitus et al., that 93% of that is in the oceans. -
robert way at 02:58 AM on 8 June 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
"KR I would strongly suggest theTrenberth Shea 2006 methodology, supported by Anderson et al 2012, as one detrending methodology worth considering."
KR,
I disagree. All these ad-hoc methods of calculating the AMO are not rationalized and if you read the article I listed before you will see that these variants of the AMO ALL struggle when it comes to deciphering the proper signal. Personally I use two versions and compare the results of each. One is the detrended first component of North Atlantic SSTs and the other is the Van Oldenborgh et al, 2009. They're both wrong but I believe that reality lies between the two. Once again reading that previous study I linked to here:
http://link.springer.com/content/pdf/10.1007%2Fs00382-013-1669-0.pdf
Should be read by everyone while discussing this issue. -
Falkenherz at 01:55 AM on 8 June 2013CO2 increase is natural, not human-caused
Thanks for the answers and sorry for the double-post, no idea how that happened.
Moderator Response:[Dikran Marsupial] no problem, easily fixed.
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