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Comments 78751 to 78800:

78751. Keith Hunter at 13:35 PM on 23 July 2011
       OA not OK part 9: Henry the 8th I was (*)
       LT @1: they amount to the same thing. Henry's Law describes the equilibrium solubility of a gas for a given atmospheric concentration. A fizzy drink is made by pressurizing the bottle with a high pressure of pure CO2. hence it has a high solubility. When the bottle is opened to the air, Henry's Law dictates that the concentration of CO2 is now too high too be in equilibrium with the new air space, so CO2 must escape from solution, hence bubbles. A related factor is that fizzy drinks are pressurized when cold to give a higher solubility. This is because the Henry's Law constant changes with temperature (as do all equilibrium constants).
78752. Jeff T at 13:32 PM on 23 July 2011
       OA not OK part 8: 170 to 1
       Christina, I guess my difficulty with the post arises from the fact that it includes only three equations (8, 9 and total carbon content = sum of carbon species) to determine four parameters (concentrations of H3O+, CO2, HCO3- and CO3--). Since Eq. 12 is the difference between Eq. 8 and 9, it doesn't provide a fourth independent relation. I suppose that you don't give a fourth equation because there are really many relations and species concentrations required. As I said, I appreciate the effort, but I don't think you've solved the problem of presenting the issue clearly. Sarah, the example computation following Figure 3 assumes that total carbon content is constant. That's why it shows a decrease in concentration of CO3--. Wouldn't an example that decreases pH by adding total carbon show an increase in CO3-- concentration, even though the ratio of CO3-- concentration to other carbon species would decrease. It may be that the ratio is more important than the concentration, but the post doesn't say so. It would be informative to remake Figure 3 to show the fractions (or concentrations, whichever is more important) of the three carbon species as a function of the total CO2 added to pre-industrial seawater.
78753. Tom Curtis at 13:04 PM on 23 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Norman @373, now that I understand that your analysis is explicitly related to the formation of supercells in the United States, I will modify my criticism from 262 and 268 above. Specifically, for that question, your sample points are sparse but can make a reasonable claim to be representative. However bundling data without regard to season and ENSO index still means your analysis is ineffective. If you really want to do citizen science on this, I have to commend you but don't imagine for a second that it is easy. In science you don't get to skip corners, and a proper study will involve multiple thousands of pieces of data, and very careful analysis. If you are not prepared to put that sort of work in, your analysis will inevitably be both shallow and flawed. What is more, it will be irrelevant because genuine climatologists and meteorologists have put in the real work, collecting tens (probably hundreds) of thousands of pieces of data, and analyzing it carefully in peer reviewed literature where any obvious and, most likely, any subtle flaw has been pounced upon by somebody with a passion for truth or to make a name for themselves. So in order to accept your conclusions from your analysis, we would have to turn our back on a great deal more data, subject to a far more rigorous analysis. Not that I am trying to discourage you from your three city analysis. I am a great fan of such analyses so long as their role is understood. That role is to learn, not to discover. By undertaking such an analysis you can more quickly gain an appreciation of the issues involved than by any other method (other than a good lecture). But you will only do so if you understand the true nature of expertise, which is knowledge of the obvious errors in a field, and how to avoid them. Think about it. You and I are not expert in meteorology. Ergo we are likely to make obvious blunders and not realize it. In contrast, genuine experts (like Albatross) will probably also make errors, but they will be subtle and interesting errors. That is, errors that are hard to avoid, and which you learn a great deal by uncovering. So the obvious attitude you and I should take is that when we disagree with the experts, we should first check rigorously why we are wrong. Not the experts, but we ourselves. Only after checking rigorously enough to become competent in the field ourselves, and after floating the idea with a few experts, a significant proportion of whom then agree with us, should we even begin to suspect that we are right. Even at that stage history shows that we are probably still making an error, but at least it will be an interesting and subtle error. Frankly, that has not been your attitude on this or any other thread on Skeptical Science. That is why Albatross is so frustrated. It is not that you keep on asking questions, a behavior which delights most experts. Its that you don't accept answers.
78754. Norman at 13:00 PM on 23 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       KR @ 365 Can't leave without this one. From your link to the peer-reviewed material on climate change. "There are no indications in this study of more intense storms in the future climate, either in the Tropics or extratropics, but rather a minor reduction in the number of weaker storms." There is significant changes to storm tracks. The thesis of this thread is "2010 - 2011: Earth's most extreme weather since 1816?" The peer reviewed article does not see an increase in the intenstity of storms, only a change in location of storms. No change in intensity of storms.
78755. Norman at 12:53 PM on 23 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Tom Curtis @ 368 Side note: To Albatross, you stated this thread has run its course. So unless someone else wishes to discuss more I will end here and go to read the Ocean acidification series (more in my field). Just wanted to respond to you Tom. You say: "Norman @363, I am not interested in debating the issue with you. Anyone who has followed this thread knows you are only interested in coming to the conclusion you started with. This is made perfectly plain in your 359 (among many other places). When looking for signs of recent increases in extreme weather you come across an extraordinary example, and immediately interpret it as proof that extraordinary examples of recent extreme weather are not evidence of increasing extreme weather. It certainly, to your mind, had nothing to do with the 2-4 degree anomaly in the US at that time. It turns out that through out the course of this debate, for you , nothing can be." I would think if would have nothing to do with the 2-4 degree anomaly in the US in January 1999. Here is why. January 1999 anomaly map. (Sorry I am not posting the graphs directly, I attempted it once but found my skill at this lacking.) February 1999 greater heat anomaly than January. January 1999: 212 tornadoes February 1999: 22 tornadoes More: January 1998 had 47 documented tornadoes. January 2000 had 21 documented tornadoes. If you do check out each of the linked maps to tornado number you can see all these years had strong temperature anomalies in January. But January 1999 soars far above the others. You would really have to stretch something to prove a causal link between January temps and tornado count in the US. Final link Does this sound sort of simialr to the topic of this thread, just switch 2010 to 1999 and there could be a match. History repeats.
78756. Rob Painting at 12:52 PM on 23 July 2011
       Why Wasn't The Hottest Decade Hotter?
       Papy - ta, already have that Solomon (2011) paper. Seems that a clutch of papers on aerosols have been published very recently. Myself and a couple of other authors are discussing them at the moment. Should have some posts on them shortly. What specifically interests me is what effect (if any) the Asian (& volcanic) aerosols may have had on ENSO, and the uptake of heat into the oceans.
78757. Norman at 12:28 PM on 23 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       KR @ 365 "On the other hand, I have to seriously criticize you for continuing to choose single or several site data sets to discuss global averages." In the series of posts above, I was not attempting to discuss global averages. Tom Curtis made the statement: "As Norman correctly points out, humidity alone is not enough for a thunderstorm; but heat and humidity are both definite factors in the strength of thunderstorms. If you increase both, ceterus paribus you will increase the frequency and intensity of thunderstorms. As it happens, increased warming is also expected to increase Convective Available Potential Energy, another key factor (see maps in my 246." I was attempting to demonstrate his point "If you increase both, ceterus paribus you will increase the frequency and intensity of thunderstorms." was not the case. In my series of posts the point was to show Tom that only a threshold humidity and heat are needed to initiate severe thunderstorms. The rest of the equation is unstable air (cold heavy air mass on top of less dense warm air). The more unstable the air, higher temp gradient between surface warm air and cold air aloft, the greater is the chance for severe weather. If you get a strong wind shear you also increase the chance for tornadoes. I did agree with Tom that if, in the United States, you would be able to send the higher energy July or August air into the unstable air of May, you would indeed create more severe storms than what are currently taking place. Your claim: "You've accounted for a significant percentage of the posts on this thread, and you have been consistently wrong. Worse, you don't seem to understand the criticisms raised. I would strongly suggest you step back and review what you know, and what you don't know, before posting here again." It is easy to say I am consistently wrong. Can you show how any of my links are not correct? Can you demonstrate that the month of May does not produces the most severe storms in the US? From your link: "How does one counter the Dunning-Kruger effect, in others or in themselves? Dunning and Kruger propose that improving a person's skills helps them recognise the limitations of their abilities. If there's a question about an aspect of climate science, the first step should be to investigate and improve understanding of the science. Odds are climate scientists have investigated the same question in the peer-reviewed scientific literature." KR, I do believe I have been doing this. Thanks to the intelligent and knowledgable Tom Curtis, Albatross, Daniel Bailey, Dikran Marsupial and many others I have recognized many flaws in my understanding and holes in my knowledge base. I have been attempting to investigate and improve my understanding of the science. I try to find peer-reviewed material for my posts, avoid blogs. One of my main reasons for posting on a scientific web site like this one. I am seeking more than one person's opinion on the issue. I want good science. From your link: "If there's no direct answer, find the closest topic and post a comment asking for answers. There are many well informed regulars who would be happy to point you towards any relevant peer-reviewed papers." My question is this: Why would weather events get more extreme when Global warming is pushing the Earth towards and equilibrium state (poles warming about twice as fast as tropics). I have been linked to articles where a computer model predicts more severe weather much later in this century. There is no way for me to validate the model. All I can determine for sure is maybe it will happen. But it does not answer my question above. I have found many sources that explain severe weather is caused by unstable air mass. You need cold air to develop this condition. If the poles are warming twice as fast as the source of the warm, moist fuel, then why wouldn't the instability of the atmosphere decrease as the Globe warms? It would have less cold air available to create the unstable air that generates severe weather. You also said: "But, please, stop selecting one to three spots in the USA only, and claiming that they mean anything compared to the global data. It's incorrect, statistically meaningless, and rather sad to watch" I think you are not understanding what I am attempting. In order to demonstrate a physical mechanism you do not have to go to every spot on earth to prove the condition is global. I am demonstrating that a reserve of cold air is necessary for the formation of most severe thunderstorms (there are always exceptions). If the reserve of cold air is reduced then the number and intensity of thunderstorms will be reduced. I choose points in Oklahoma and Texas because these are the areas that produce the most severe thunderstorms not just locally but globally. I demonstrate that May has the most severe storms in those states (tornadoes, rain, hail). I demonstrate that without the cold air aloft the highly energetic and moist air of July and August do not produce near the number of severe storms or rain events. If you drop a ball in your house and have supporting documentation of gravity, do you need to come to my house and drop a ball to test the idea? If I can demonstrate that warming of air in Texas and Oklahoma will not lead to more severe storms (over a 100 year period for precipitation and at least 50 years for tornadoes), why would I need to extend the area? I am demonstrating a mechanism that is supported by the literature (I have linked to multiple sources which confirm the mechanisms needed to produce severe storms). If the mechanism is a valid one, it will work anywhere on the globe.
78758. Norman at 11:43 AM on 23 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Tom Curtis # 370 "Norman @367, I do not believe that I have ever said that warm moist air is the major ingredient in the formation of severe weather." What you had said "From an earlier post by Tom Curtis at 258 "As Norman correctly points out, humidity alone is not enough for a thunderstorm; but heat and humidity are both definite factors in the strength of thunderstorms. If you increase both, ceterus paribus you will increase the frequency and intensity of thunderstorms. As it happens, increased warming is also expected to increase Convective Available Potential Energy, another key factor (see maps in my 246" That is where I misquoted you, sorry. You used the words "definate factors" and I switched that to "major ingredients" also you said "thunderstorms" and I changed that to "severe weather". My flaw. I stand corrected.
78759. Doug Mackie at 11:05 AM on 23 July 2011
       OA not OK part 8: 170 to 1
       Thank you Sarah. We did think about a more complex figure with multiple axes that included changing total carbon but we felt it would not have been easily understood.
78760. Papy at 10:49 AM on 23 July 2011
       Why Wasn't The Hottest Decade Hotter?
       If so and to complete, there seems to be a complementary study in my french source of the "Institut Pierre Simon Laplace" : "The persistently variable « background » stratospheric aerosol layer and global climate change" (Solomon et al, 2011).
78761. Sarah at 10:25 AM on 23 July 2011
       OA not OK part 8: 170 to 1
       Jeff T: Figure three shows the distribution of carbon in the three forms when the pH is at different levels no matter what makes the pH change. If you put carbonate and/or bicarbonate in a beaker and then add nitric acid the proportions of each form of carbonate will change. The proportions will also change if you add any other acid, hydrochloric acid, acetic acid (vinegar), or carbonic acid. If you use CO₂ to lower the pH then the fractions behave just like the figure shows, even as the total amount of carbon increases. You can also increase the pH by adding any kind of base, for example sodium hydroxide. And you can increase the pH by adding carbonate (CO3₃^2-). In that case the total amount of carbon also increases while the fractional distribution shifts to the right on the graph. Removing CO₂ decreases the pH (by eq 8 it removes H₃O⁺) and so the fractional distribution again shift right, even though this time the total amount of carbon decreases.. Figure 3 is very powerful precisely because it separates the total amount of carbon from the fraction in each form.
78762. LazyTeenager at 10:01 AM on 23 July 2011
       OA not OK part 9: Henry the 8th I was (*)
       So the next thing to find out is whether seawater is above or below the equilibrium amount in CO2. A nice global map would be nice. Seems to me that some in climate sceptic land have seized on the idea that the ocean is emitting CO2, but I suspect this idea is a matter of faith for them and not based on evidence.
78763. LazyTeenager at 09:49 AM on 23 July 2011
       OA not OK part 9: Henry the 8th I was (*)
       Correct me if I am wrong but I would have thought that the fizzing of carbonated water relates to the solubility (maximum dissolvable amount) of CO2 in water and not to the Henry's law equilibrium. The temperature dependence would be in the same direction but the actual relationship would be different.
78764. Tom Curtis at 09:39 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red @114, again to just make sure we are on the same page, unless the climate system is very close to a tipping point (within 0.2 degrees c), ENSO fluctuations cannot result in a "step change" in global mean temperatures. Another way to look at it is this, if you have a period of predominantly La Ninas and follow with a period of predominantly El Ninos, in a period of no underlying trend, in the immediate period of the transition that will introduce a spurious trend to global mean temperatures. But outside of any interval that ranges across the point of transition, that change will introduce no trend to the series. Do you agree? I believe that this is a straightforward conclusion from the fact that there are no long term consequences from an ENSO fluctuation. I am seeking this clarification because you qualify your response by mentioning La Ninas, whereas the lack of long term effect of an El Nino is independent of any follow on La Ninas.
78765. Rob Painting at 08:46 AM on 23 July 2011
       Why Wasn't The Hottest Decade Hotter?
       Papy - thanks for the Vernier (2011) abstract link. I'll see if I can track down a copy of the paper - it might be worth a post.
78766. Doug Mackie at 08:02 AM on 23 July 2011
       OA not OK part 6: Always take the weathering
       Hi Paul, I see that Doug (comment 20) suggested you calculate the pH of rainwater in order to answer your question about the change in rainwater pH (comment 19). How did you go with this? You are correct - biochar soil remediation may help reduce atmospheric CO₂. However, it is unlikely that the carbon sequestration would be any faster than the 150 years it has taken to put the CO₂ into the atmosphere. This is unlikely to reverse ocean acidification (the topic of these posts) in any remotely useful time frame.
78767. Eric the Red at 06:40 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Sphaerica, You still have a time frame when the ENSO index is essentially zero. The goal posts have not moved. As I stated previously, the period starting in 2007 may suffice, if it persists. Something similar to 1950 - 1977.
78768. Byron Smith at 06:08 AM on 23 July 2011
       China, From the Inside Out
       @Paul Magnus: Regarding not flying and people listening, I have had precisely the same experience.
78769. Bob Lacatena at 04:55 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       123, Eric the Red, Gee, how very nefarious of me. Okay, lets start at 1995, which was during an El Nino, and includes the world temperature record 1998 El Nino at the start of the period. We'll end in 2009 (during a La Nina). or, if you prefer, we can end in 2010, again in the midst of a moderate La Nina. Any other cherries you'd like unpicked?
       Response:

       [DB] Perhaps this is relevant?

78770. Albatross at 04:39 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Sorry, please replace "Tom" with "Sphaerica" in #124 above. Sorry Sphaerica!
78771. Bob Lacatena at 04:38 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       118, Eric the Red, So the goal post moves from "in the face of repeated La Ninas" to "a period of predominately La Nina." Which means what? We have to wait until the roll of the dice generates a period with 8 out of 10 years being in a La Nina phase in order to prove to you what all of the evidence, logic, numbers and statistics already show? This is equivalent to my recent question to you about what it would take for you to accept AGW, and your answer was a temperature increase over the next 26 years equal to that of the past 26 years (meaning you will admit to nothing until 2037).
78772. Albatross at 04:38 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric, Thanks for dragging this discussion down. I can assure you that Tom is not in the habit of cherry-picking. You asked for a period satisfying certain conditions, and he found one (starting in 1999) and then presented the UAH data for that period. I then checked the MEI data for Tom's window and the mean MEI was in fact negative, so was the ONI. So you are making ridiculous accusation-- the very nature of your request made it necessary to identify a time window when the ENSO was predominantly negative (La Nina) but during which the planet warmed. So instead of accepting the evidence as a true skeptic would do, you start making fallacious accusations. IMHO you owe Tom a sincere apology.
78773. Eric the Red at 04:31 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Albatross, I was using Sphaerica's orange box which appears to encompass the timeframe 1998-2011. He conveniently changes to 1999 for his temperature plot, thereby removing the highest values from 1998, and arriving at his cherry-picked trend. This is one of the fallacies of using short-term data. Had he chosen a similar start date for his temperature plot, he would have a negative trend.
78774. Rob Honeycutt at 04:21 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric @ 121... Well, I wonder if you removed changes in solar forcing if you'd start to see that accelerating trend. You'd also have to remove Asian aerosol effects as well. I think there are probably a lot of reasons to think the underlying CO2 induced warming trend is, indeed, accelerating.
78775. Eric the Red at 04:11 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Dikran, Yes! When the PDO or ENSO signal is removed from the temperature records, the oscillation disappears, and a fairly linear increase results. There has been no acceleration nor deceleration, and no reason to expect any.
78776. Albatross at 04:09 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric claims "The composite ENSO index for your entire boxed area is just slightly below 0 (in fact it was positive until March, 2011)" It is not clear exactly which period we are referring to, Tom seems to have plotted those UAH data from January 1999 onwards. The mean MEI for 1999 (Jan/Feb)- present (May/June) 2011 is -0.085. The mean MEI until Feb/March was -0.24. The ONI also give negative mean values between January 1999 and March 2011, and until June 2011. Yet, the planet has warmed. Eric, you are arguing/debating in circles, and it would really help if you backed up your assertions with data and citations-- like the extreme thread, you are again talking though your hat here. Note how the global temperatures associated with the 2007-2008 La Nina were warmer than those in 1999-2000, and how global temperatures during and shortly after the 2010-2011 La Nina were warmer than both previous events. It will happen relatively soon (within a decade or so) that even a year with a moderate of strong La Nina will be warmer [Global temperature anomaly, GTA] than 1998, a year with a the second-strongest El Nino on record. In fact, the planet was warmer in 2008 (La Nina, GTA = +0.44 C), 1999 (La Nina, GTA = +0.32 c) and 2000 (La, Nina GTA = +0.33 C)were all warmer than 1983 (El Nino, GTA = +0.25 C), and 1983 was the year of the strongest El Nino on record. ENSO etc. are oscillations superimposed on a long-term underlying warming trend because of the radiative forcing from anthro GHGs. They can modulate the trend, and that is it.
78777. Dikran Marsupial at 03:57 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red There appears to be a contradiction here, perhaps you can explain. If PDO does not cause warming, then there is no reason to think that there is a genuine oscillation in temperatures due to the PDO (and instead it is either a coincidence or the causal relationship is in the other direction). In that case there is no reason to think that the current upward swing of PDO is causing the acceleration (what acceleration?) in the upward rise of temperatures. I should point out that there have been several regression alanyses performed (and discussed at SkS) where the effects of ENSO are removed from the temperature time series and you get a pretty steady approximately linear rise in temperatures. A linear rise in temperatures is exactly what you would expect from an exponential rise in atmospheric CO2.
78778. Eric the Red at 03:27 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Dikran, It is not a matter of either CO2 or PDO is causing warming. During the past 130 years, the CRU temperature record has shown an increase of ~0.6C / century. Overlain on this increase are two 60 year cycles with an amplitude of ~0.3C. The oscillation is not affecting the underlying trend. Some people are preferring to ignore the oscillating effect and claim that the temperature rise has accelerated during the upward cycle. This has led to some added explaining during the recent period. Sphaerica, notice how the temperature responds to the ENSO index? La Nina conditinos from 1999-2001, El Nino for the next 5 years, La Nina in 2008-9, El Nino in 2010, La Nina in 2011. The composite ENSO index for your entire boxed area is just slightly below 0 (in fact it was positive until March, 2011), so it does not constitute a period of predominately La Ninas. If we see repeated conditions such as existed from the end of 2007 forward continuing, then I would agree. We need a warm summer, since the first 5 months of 2011 were the second coldest during your orange box (2008 being colder).
78779. Rob Honeycutt at 03:10 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Sphaerica... That chart gets even more interesting if you plot it with a 12 month mean. [Here.]
78780. Bob Lacatena at 03:00 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       114, Eric the Red,

       In answer to Sphaerica's question, it would take a period of rising temperatures in the face of repeated La Ninas for me to abandon the idea that ENSO (or PDO) has a climate impact.

       Good. It's settled, then. See 2000-2011. 4 strong La Nina's (boxed in orange): Rising temperatures: I should point out that we're currently on a path to the second warmest summer ever, despite the recent end to a moderate La Nina, and without El Nino conditions... and during the cool phase of PDO (which supposedly started in 2008). Current Temps
78781. Dikran Marsupial at 02:56 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red wrote: "I am not arguing the this [judging from context ENSO] is responsible for the 20th century warming." If you are arguing that PDO has an effect on climate then yes you are, becuase the correlation we have been discussing is between PDO and the surface temperature record, which is pretty much the 20th century (with a few decades hanging off the ends). "My point is that during the short term, this oscillation can affect temperatures," In that case it is a pointless point as pretty much everybody with an interest in climate know perfectly well that ENSO has an effect on surface temperatures. It is perhaps not surprising you are being misunderstood. If your point was about the short term effects of ENSO, then it was probably a bad idea to talk about PDO which is the long term behaviour of ENSO.
78782. Eric the Red at 02:41 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Tom, Thank you for that in depth response. I agree that the long term climatic effects of ENSO variations is 0. Over time, warm El Nino years (2010) are balanced by cold La Nina years (2011). Over the past century, we have had periods of stronger and more abundant El Ninos, which were characterized by higher temperatures, followed by periods of stronger and more abundant La Ninas, resulting in cooler temperatures. These cycles can be overlain atop the warming trend of the 20th century. This is not unlike what Tamino has done with his recent analysis with aerosols and ENSO. The ENSO index was largely positive, with an abundance of EL Ninos from 1977 - 1998. Prior to that, it was largely negative, with an abundance of La Ninas. Since then, we have fluctuated between the two without a strong signal until this year's strong La Nina. In answer to Sphaerica's question, it would take a period of rising temperatures in the face of repeated La Ninas for me to abandon the idea that ENSO (or PDO) has a climate impact. I am not arguing the this is responsible for the 20th century warming. My point is that during the short term, this oscillation can affect temperatures, and should not be confused with other factors. There are some on this thread that seem to think that just because I acknowledge these effect that I believe that the entire post-industrial warming was due to PDO. That is simply not the case. That would be like saying that Hansen believes the entire observed warming was due to the changes in aerosols, because he claims the recent emissions by China have cooled temperatures.
78783. Dikran Marsupial at 02:32 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red I think you have also misunderstood Sphaerica. He is is clearly talking about the Earth's energy budget, which is purely determined by radiation (convention only causes differences in the distribution of heat energy within the Earth). Hence Sphaerica is absolutely correct. I guessed that you might be arguing that PDO has an indirect effect on radiation (even though you did not actually say that) as that is the only way in which your position seemed to have any logical consistency (see my previous comment about how to deal with perceived inconcistencies). However, as I said, in order for your hypothesis to be worth considering you need to take the next step and show that PDO is actually linked to outbound IR radiation. You have not done so. Pointing out a paper that mentions PDO and stratospheric temperatures is not evidence, especially as the paper seems to be about the polar stratospheric vortex, which is not the same thing as global stratospheric temperatures or outbound IR radiation. Again your posting style comes across as unhelpfully arrogant; there was nothing non-sensical about spaerica's analogies, and rhetorical dismissal of someones scientific argument does not encourage further discussion.
78784. Eric the Red at 02:16 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Dikran, Maybe I did misunderstand you. Looking closer at your comment, that appears to be the case. We seem to agree that ENSO can cause convectional changes. Therefore, what is preventing the additional heat in the atmosphere from radiating out to space? Sphaerica seems to think that energy can only be radiated, and dismisses convection through nonsensical analogies, which is where I perceived your contradiction. Here is just one paper on then ENSO effect on stratospheric temperatures. http://www.atmos.washington.edu/~cig4/tropprecursorsrevisedv3.pdf
78785. Bob Lacatena at 02:11 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       106, Eric the Red, If you have not already done so, I very, very, very strongly suggest that you go read: Blaiming the Pacific Decadal Oscillation post here on Skeptical Science (from March 5, 2011). It contains a lot of information that you'll find useful, including, most importantly, a (failed) effort by Dr. Roy Spencer to attribute current warming to the PDO. Please read it thoroughly. I also suggest following the links to actually read the source papers, in particular Schneider et Al (2005).
78786. Bob Lacatena at 02:00 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       106, Eric the Red,

       I never said anything about a proposal to wait a few decades.

       Would you care to clarify exactly how long we should wait to evaluate the impact of a 60 year oscillation, just to make sure that we're not missing anything, and that maybe climate change isn't really happening and it's all just part of the natural ebb and flow of the climate? [Hint: I've been here before with you. It starts with "we don't know" and moves on to "we should wait to be sure" and ends with "oh, a few decades should do it."] After all, we know so little (according to you). So, we're supposedly at the end of the warm phase of the PDO. How long will temperatures need to continue to rise for you to abandon the idea that there is anything of interest (as far as long term, substantive climate impacts) in the PDO?
78787. dana1981 at 01:45 AM on 23 July 2011
       Lessons from Past Climate Predictions: William Kellogg
       The site is Skeptical Science - we're real skeptics. Although it had a strong physical basis, Kellogg's prediction had some problems which are useful to learn from. Those who don't learn from past mistakes are doomed to repeat them. Easterbook comes to mind. James Wight is going to try and work on a post detailing the various measures of climate sensitivity this weekend.
78788. Tom Curtis at 01:40 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red @102, I think you and the other participants on this thread are talking past each other, or at least I hope you are. To see what I mean, let's start with basics on ENSO. Fundamentally, the ENSO involves a 'sloshing' of water across the equatorial Pacific. During neutral conditions a large body of warm water lies below the surface in the Western Pacific, while during El Nino's some of that water spread across the surface of the central and Eastern equatorial Pacific. So far this is just moving heat around. However, because the warm water is at the surface, it is now able to effect the climate in a way it was not previously able to do. At a minimum it will result in greater surface radiation at the equatorial Pacific in that there is a greater surface area of warm water able to radiate. All else being equal, this will result in greater radiation to space both in that part of the IR spectrum outside the CO2 and H2O absorption frequencies, and in those frequencies because the upper atmosphere will also be warmed. Further, it is very probable that there will be climate feed-backs to the warm water. That is because physics does not care whether warmer surface waters are a consequence of radiative forcing, or simple 'sloshing' of oceanic waters. The evaporation rates will increase, the convection increase, and the radiation increase will be the same for 1 degree increase in middle tropical Pacific waters due to radiative forcing or due to an El Nino. What is more, we need those climate feed-backs to explain the strong effect of ENSO on global temperatures. So far I'm sure you will agree. However, there is one crucial difference between an ENSO oscillation and warming due to radiative forcing. The ENSO oscillation is short term. You can model a feedback by successive summing of a multiple of the initial signal. Suppose you introduce a temporary signal, when the initial feedback response is 0.6 * the initial signal. Then at T0, the output will be the initial signal. At T1 the output will be the response to the initial signal. At T2 the output will be the response to the response to the initial feedback, and so on. For any response greater than 0 and less than 1, the result will be a self damping feedback response, and will quickly fall towards zero. However, if we leave the initial signal on permanently, then at T0 the output will be 1 (the initial signal). At T1 the output will be 1 + the response to the initial signal. At T2, the output will be 1 plus the response to the signal at T1, plus the response to the response to the signal at T0, and so on. Unlike the the case where the initial signal is removed after T0, in this case we will get a positive feedback that will multiply the signal. If the feedback factor is 0.6, the final output after a while will be 2.5 times the initial signal. Again the system is stable for feedback factors greater than 0 but less than 1. The crucial point is that feedback responses initiated by ENSO oscillations will follow the first model because the initial signal is temporary. In contrast the feedback response to radiative forcing from increased GHG will follow the second. And because the response for ENSO oscillations follow the first pattern, their long term effect on climate is zero. This is the point the other participants in this thread appreciate but that you do not seem to get. Even if you have multiple El Nino events in succession, so long as there is a short interval between them they will introduce no trend to global temperatures. They will slightly raise average global temperatures for a short time, but only because the average will be the mean of a number of warm years. To be clear on this point, the difference between such a succession of ENSO's is that it will not effect the expected temperature of cool years because the cool years will be largely unaffected by El Nino feedbacks. In contrast, the genuine trend introduced by GHG radiative forcing will increase the expected temperature of both cool and warm years (which, as an aside, is what we have seen in the temperature record). I think a number of important points follow on from this analysis, but I won't go into them until we are sure we are on the same page.
78789. Bob Lacatena at 01:35 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       106, Eric the Red, You seem to understand that if an El Niño (or the PDO in a warm phase) heats the atmosphere, that this would result in a loss in energy, cooling the planet. So the short term effect is to raise observed global temperatures, while at the same time reducing the actual temperature of the planet. What now remains is to quantify this effect, and to establish some mechanism whereby this effect could account for the continual accumulation of heat over time frames that exceed one half of the cycle (30 years), thus raising global temperatures by a whopping 0.8˚C using an anomaly that encompasses less than 1/6th of the earth's surface.
78790. Dikran Marsupial at 01:16 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red Your rather arrogant tone does you no favours. If your hypothesis is correct, it is easily verifiable. Can you show that ENSO has an effect on high-trophospheric and stratospheric temperatures? If so, you ought to be able to work out the difference in outbound IR radiation that would result. Pointing out a correllation between PDO and surface temperatures is the start of some science, the next step is to look at other datasources to see if your hypothesis is feasible. It is ironic that you complain that Spherica has misquoted you and then say that I contradict Sphaerica. I didn't and if you think I did, then maybe you didn't understand the point being made. I have found over the years that generally when I think someone is contradicting themselves it is my understanding that is faulty, and asking questions that explore the contradiction is generally a better way of resolving the issue.
78791. Rob Honeycutt at 00:37 AM on 23 July 2011
       It's cosmic rays
       Oh, that slide comes from Alley's AGU A23A lecture. [Source]
78792. Rob Honeycutt at 00:36 AM on 23 July 2011
       It's cosmic rays
       Given Musch 2005 I think these GCR guys have an uphill battle. Not only do they have to explain a highly complex mechanism they are going to have to explain why their theory works other times but didn't work in this case. The deck is pretty well stacked against them.
78793. Papy at 00:33 AM on 23 July 2011
       Why Wasn't The Hottest Decade Hotter?
       Thanks Rob for this article, even if I'm still not totally convinced about the relevance of the choice of the niño-flawed 1998-2008 decade limits as we talked before, which might finally be more blunderer in a certain way than deliberate. #69, David Lewis : "Hansen finishes the talk with something I don't understand about Pinatubo: "And one of the interesting effects is the volcanoes. The Pinatubo aerosols gave us this big negative forcing and a cooling factor in 1991, and that only lasted for a couple of years. You wouldn't think it would be affecting things in the last ten years, but actually it does. Its because after the aerosols disappear, they're no longer influencing the amount of sunlight absorbed by the planet, but they're still influencing the heat radiation to space because they caused a cooling of the ocean, and therefore you continue to get this rebound effect after the volcanic aerosols are gone and that then causes a decline in the radiation imbalance in the last decade" This new study may provide a subsidiary volcanic explanation to the Pinatubo's : "Major influence of tropical volcanic eruptions on the stratospheric aerosol layer during the last decade" (Vernier et al, 2011). But what are these minor tropical volcanic eruptions causing an important source of stratospheric aerosols ? Were they proved to have been more active during this last decade ?
78794. Kevin C at 00:31 AM on 23 July 2011
       Milankovitch Cycles
       Ah, thanks, that helps a lot! I've encountered these plots in catastrophe theory but didn't recognize the name. The negative gradient section is never visited - rather the diagram illustrates that with too big a change in insolation you jump to the lower curve (and vice-versa). That clears up most of my confusion straight away. I'll look into Ray's paper as soon as I can.
78795. Eric the Red at 00:16 AM on 23 July 2011
       It's Pacific Decadal Oscillation
       Sphaerica, How do you expect to explain something that is not my exact quote? You have merged two different quotes (which are not even exact) into one in an attempt to corner me. Energy is radiated from the atmosphere into space. Energy is transfered within the atmosphere through several methods. Your ridiculous analogies only point to your repeated attempts to dispute arguements through inane logic. Dikran at least understands that much. Now if he can only understrand that if more heat is transfered from the surface to the atmosphere, that more heat can be radiated out to space, then we have made progress. Saying that Sphaerica is correct, and then contradicting him in the next breath, seems illogical. Sphaerica, your last post seems to be a collection of snipits similar to a political candidate who takes bits of highlights reels of his opponent and attempts to piece them together to make him sound like he is saying something which he did not. I never said anything about a proposal to wait a few decades. Probably the only accurate statement in your last post is that you thing we know more, while I think we do not. If we know so much, why is the uncertainty so great? (i.e. more than 100% for climate sensitivity to atmospheric CO2) Or why are Trenberth and Hansen arguing about whether the missing heat is lost in the oceans or radiated out to space? I will refer you a quote. "The more we learn, the less we know for sure." - Sheridan
78796. Chris Colose at 23:56 PM on 22 July 2011
       Milankovitch Cycles
       Kevin C, You are right that the intersections are energy balance points, where the solar flux equals the outgoing radiation. Having a temperature-dependent albedo is one way to get the structure in Fig. 9. I just said that the global albedo can range between 0.2 and 0.6 between two specified temperatures (lower albedo in the warm case, higher in a cold case) and parametrized the OLR to give a simple greenhouse effect, then made the plot. You can also make a plot of temperature vs. CO2 (instead of solar insolation). Obviously this bifurcation structure in this post is a very "theoretical" and simplified one, so I wouldn't take it too seriously when trying to interpret glacial/interglacial changes, etc; in the real world there might be many stable equilibrium points, or it might take a sizable forcing to push away the climate from an unstable point. In this plot, the limits of ~1300 W/m2 and ~2000 W/m2 are transition regions, so for example, if you start off in a warm climate and then gradually lower the solar constant, the climate cools smoothly; once you cross the ~1300 W/m2 mark, the snowball is initiated and you descend abruptly into the cold solution regime. Because of the high albedo, it now takes a higher solar constant (~2000 W/m2) than the original value to return back to the initial state. Actually getting out a snowball in the real world is still a pretty unresolved problem, but it probably takes a very large amount of CO2, as we see in the geological record for the Neoproterozoic glaciation. And, if it's too cold, excess greenhouse gases will just condense out on the surface, so it's not obvious that many planets at a distant orbit (or the outer edge of the "habitable zone") can even get out of a snowball, at least until the star continues to get brighter. A lot of papers about snowball Earth discuss this, and there's a detailed treatment in Ray Pierrehumbert (and others) recent Neoproterozoic review paper that you can get from his web page (his textbook does as well, and so does Dennis Hartmann's in the ice-albedo feedback discussion). You can also talk about it in connection to a runaway greenhouse, or perhaps even smaller-scale phenomena like abrupt climate change, but there's debate as to whether this is an artifact of simpler models for many processes relevant to the real world. In this case, the key point is that the climate can equilibriate at multiple temperature solutions, and where it actually is depends on the history it took to get there. The stability criteria is equivalent to stating that the slope of the absorbed solar curve is less than the OLR curve at the intersection point, but I would read these works cited above if you want a general overview of the mathematics or more detailed treatments.
78797. Bob Lacatena at 22:36 PM on 22 July 2011
       It's Pacific Decadal Oscillation
       102, Eric the Red, You show a constant desire, topic after topic, to cling to what "we do not understand" as a reason to put existing theory on hold until we know more. From your most recent comment (102) alone: Just because we cannot explain why... ...ignoring what we do not understand. ...the cause and effect relationship is not fully known... ...we do not know yet. Look at your comments on other threads. Every single topic always dissolves into a "what if" (and usually one that contradicts known and tested theories) followed by "we just don't know," which is inevitably followed by the proposal to wait a few decades, just to be sure. In this case, we actually know a lot. We know how ENSO works, we know how greenhouse gases work, we know how radation works. We know a lot about ocean currents, air masses, and a million other things. Given all that we do very firmly know, it is very hard for a rational person to look at an ill-defined, un-bounded and completely unexplained event (PDO) and to focus on it as an explanation for events that are already properly well explained by existing knowledge and theory. I'm not saying that we know everything. I am saying that you are exaggerating what we don't know and then using that position to cling to something that at the moment has no substance whatsoever.
78798. Bob Lacatena at 22:27 PM on 22 July 2011
       It's Pacific Decadal Oscillation
       102, Eric the Red, Please explain to everyone how "convection through winds and waves transfers energy out of the planet into space" (your exact words). There is a basic concept here the you are ignoring, and that is the fact that the earth is a mostly closed system. The only way to get energy into or out of the system is through radiation. Period (well, that and shooting rockets full of molten lead out into space). If you want to propose a mechanism by which either ENSO or PDO can affect global temperatures over long time frames, please by all means do so, but you can't go with merely "wind, currents, waves, energy... presto!" Please point to the ocean waves that travel from here to the moon, or the trade winds that blow from Japan to Mars.
78799. Dikran Marsupial at 22:07 PM on 22 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red Sphaerica is absolutely correct. The only way the Planet can lose enegry is by radiation. There is no condiction or convection becuase the Earth exists in a hard vacuum. This means that while ENSO may cause changes in convection within the atmosphere, that is still only a redistribution of energy within the planet. It can't change the heat content of the planet. Your argument that e.g. atmospheric pressure affects ENSO is a pretty good argument that PDO is a measure of the effect of the Earth's temperature on ENSO, rather than the other way round. Thus it is an argument against attributing changes in temperature to the PDO. "Two complete cycles of the PDO corresponding to the cylces observed in the temperature records seem to have a higher likelihood than solar heating and aerosol cooling just happening to occur at 60-year intervals." Nonsense, if the temperature change were the response to PDO, you would need to explain why the physics of solar forcing and albedo from aerosol scattering is wrong. Again you are putting statistics ahead of physics; as a statistician I can tell you that is a mistake. It might be reasonable to assume some underlying cyclic process after seeing two cycles in a time series if that were all the information you had. However in this case, it isn't all the knowledge we have, if we receive more TSI from the Sun, temperatures will increase and the physics to work out by how much is not exactly rocket science.
78800. Eric the Red at 21:53 PM on 22 July 2011
       It's Pacific Decadal Oscillation
       Tom, That is probably the closest we have come to agreeing on anything. Sphaerica doesn't understanding, or possibly does not want to understand, the effects of ocean currents and winds. This is exemplified by his statement that although ENSO can change temperature it cannot change the heat content. The ENSO effects are indeed short term. Last year's El Nino generated higher temperatures, while this year's La Nina resulted in lower temperatures. Over time, they tend to balance out. However, as you mentioned, any change in the system towards a greater occurrance or strength of EL Ninos or La Ninas will affect the overall climate. The error in Sphaerica and Phillipe's arguments is thinking that radiation in the only means of transfering energy. This is narrow thinking. Convection through wind and waves can transfer significant amounts of energy. The energy is not merely "shuffled around," but can be moved, transferred, and ultimately lost into space. Not to mention the heat loss associated with evaporation. As I stated previouisly, we know that the EL Nino / La Nina patterns are driven by the strength of the trade winds, which in turn are cause by changes in atmospheric pressure. Just because we cannot explain why these changes are occurring, does not mean that they are not happening. That is the fools approach. It is not a magical system either, but very real. The moderator appears to be echoing this sentiment about ignoring what we do not understand. Not exactly a good scientific approach. It should be obvious to the moderator who is using scientific, peer-reviewed literature in this argument, as opposed to those who are trying to hand-wave away any connection as if it did not exist. The PDO may not be the best measurement of what is affecting the observed changes. Other prefer to use the SOI or other permutations thereof. Readily dismissing these parameters because the cause and effect relationship is not fully known does not lead to scientific advances. Science will tell us to investigate these relationships to see if they occur by more than chance. Two complete cycles of the PDO corresponding to the cylces observed in the temperature records seem to have a higher likelihood than solar heating and aerosol cooling just happening to occur at 60-year intervals. As to whether the PDO drives ENSO or is simply an index of ENSO-related events, we do not know yet. However, that does not mean that there is nothing driving the changes observed recently, nor does it mean that a "physical" mechanism does not exist which affects climate. Finally, Dikran, there is the possibility that changing temperatures are causing changes in the oceans, and I have said repeatedly that science starts with these types of relationships.
       Response:

       [DB] As Dikran and Sphaerica have already aptly shown, you are arguing from both an incompleteness of understanding and ignorance.  Your refusal to come to grips with that is an illustration of confirmation bias and the Dunning-Kruger Effect.  When your errors are pointed out to you, you then resort to the childish "I'm not wrong, you are".  Your position is unsupportable by the physics of the natural world which, contrary to the hand-waving and dismissive airs displayed, we actually have a pretty good understanding of (it ain't exactly rocket science or brain surgery).

       How about getting a better grounding in the science itself before wasting everyone's time?  Or is that your entire aim here at SkS?

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