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Comments 78701 to 78750:

78701. 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.
78702. 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.
78703. 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.
78704. 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]
78705. 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.
78706. 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 ?
78707. 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.
78708. 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
78709. 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.
78710. 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.
78711. 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.
78712. 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.
78713. 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?

78714. Dikran Marsupial at 19:30 PM on 22 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red You are missing the point (i) you have provided no evidence that the PDO is anything more than an index of ENSO and (ii) the direction of the causal relationship could equally be in the opposite direction and the changes in surface temperature (or more correctly the changes in forcings) may cause the PDO rather than the other way around. Noticing a correllation is where science starts, not where it finishes. If you notice a correllation, but can find no causal mechanism with sufficient power to explain the strength of effect, then the hypothesis based on that correllation has only very weak support. It would be unscientific to view such an hypothesis as reason to seriously doubt an alternative hypothesis, for which there is a causal mechanism with sufficient power to explain the results. Another important part of science is responding to criticisms of your position, in this case that you may have the direction of the cuasal relationship the wrong way round.
78715. Kevin C at 19:14 PM on 22 July 2011
       Milankovitch Cycles
       OK, I'm now intrigued by fig 9 - the bifurcation diagram. Can I read more about this somewhere? (That question may have a very short answer, which makes the rest redundant!) My curiosities include: - Intersections presumably represent energy balance? - The unstable equilibrium is interesting. Increasing insolation there decreases temperature? - Is there any way to tell from the diagram alone which intersections are stable and unstable? - How do the curves vary over time? Clearly changes in insolation shift the straight line left and right. Then forced CO2 changes change the shape of the curved line? Over what timescales does the curve change? - How does this figure relate to the glacial cycle? ... In a glacial, does the earth slip down to the unstable equilibrium, and then bounce back up because it is unstable (the temp change looks too big though)? ... Or do glacials correspond to the curve moving (seems more likely)? ... Or is the glacial/interglacial cycle just oscillation around the stable equilibrium? (And the increasing amplitude over the past million years represents a steepening of the curve?)
78716. Bern at 18:15 PM on 22 July 2011
       Lessons from Past Climate Predictions: William Kellogg
       Artful Dodger: yes, it's much easier to never-be-wrong. I know a few people like that, they seem quite happy that way, right up until they come face-first with something that flatly contradicts their opinion. Then the dancing begins, as they try to somehow reconcile the new incontrovertible facts with their contradictory position. Of course, this isn't a new left-wing conspiracy tactic at all, just a very old one. That is, if you consider the scientific method to be left-wing and conspiratorial... (and we certainly know there are plenty of people out there who do assert that equivalence!) I'll add that I'd also like to read a nice article about the inter-relationship between different sorts of equilibrium & sensitivity & slow/fast feedbacks. Just in case you SkS authors were sitting around twiddling your thumbs, or something... :-D
78717. Bern at 18:09 PM on 22 July 2011
       French translation of The Scientific Guide to Global Warming Skepticism
       Some days I feel rather depressed that other languages weren't taught much when I was a kid... I know about enough French & German to say "Sorry, can't speak your lingo, can you speak English?" But a big Thank You! to the folks doing these translations. It's all too easy to forget, sometimes, that most of the world doesn't speak English as their native tongue!
78718. Artful Dodger at 16:12 PM on 22 July 2011
       Lessons from Past Climate Predictions: William Kellogg
       How refreshingly honest! Analyze your predictions and correct as necessary. Must be a new left-wing conspiracy tactic. Isn't it just easier to never-be-wrong in the first place?
78719. Paul W at 16:05 PM on 22 July 2011
       OA not OK part 6: Always take the weathering
       I agree with the lack of pH change from CO2 the other concern was with desperate measures like SO2 injected high into the sky to lower solar insolation. There may be a back fire with the weathering of rocks from the sulphur cycle increasing. Still the amount of sulphur will be small compared to the cooling effect. This comes back to my preferred OA remediation, (after ASAP end to fossil fuel use) charing of the organic waste stream (gardens, farms) and the build up of soil microbes as a result of the extra charcoal in the soil. Since about 60 giga tonnes is turning each year in the carbon cycle that is part of land based life, the task is not small but with out the above hazards. I wonder if we will be using waste heat from bio-char ovens to get warm in the coming generations? There is other buffers not just the ocean that will tend to unload CO2 back into the air after a reduction of the air born CO2 level begins. More reason to try and end fossil fuel use ASAP. Apart from that it's still a Gordian knot. I like to have an end point in a long journey like investigating ocean chemistry. :-)
78720. Doug Mackie at 14:36 PM on 22 July 2011
       OA not OK part 6: Always take the weathering
       Paul W, we are glad to see you are paying attention. Many of the things you ask are dealt with in the rest of the series. However one point may help you right now: The thing about future weathering is that the pH of rain just won't change much under realistic future atmospheric pCO₂. As a chemist you will be able to approximate the answer quite easily. You will need to the Henry's law coefficient for CO₂ in freshwater (see next post) and K₁ for H₂CO₃ in freshwater. (Or include K₂ for an exact solution). This change in rainwater pH will make only a slight difference to weathering that will take a long time (geologically long) to make a difference to the ocean carbon speciation. It is certainly possible to rapidly manipulate the chemistry of an aquarium. Then again, if it all goes badly it is possible to empty the aquarium and refill it. We suggest that the time and energy constraints on mining, grinding and dispersing any mineral precludes such an option as a realistic remediation for the ocean.
78721. Albatross at 13:47 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Tom, I just wanted to say that I very much appreciate your efforts on this thread. Don't feel that they have been for naught, I am sure that your posts have resonated with those many reasonable, informed and truly skeptical people out there. At this point it really appear that the contrarian is interested in dragging out the "debate" and arguing. Fortunately, very early on already science and reason yet again won the day; this thread has run its course.
78722. Tom Curtis at 13:27 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       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 I do say is that for most conditions, increasing temperature and moisture content will increase the risk of severe storms. In many locations, however, the factors that increase temperature will also alter other factors so that overall risk is reduced. Taking Queensland again, increased temperature may well increase the risk of cyclones all else being equal, but ENSO dominates temperature variation in Queensland, with El Nino's decreasing the risk of cyclones. Consequently global warming is expected to decrease the frequency of cyclones in Queensland, but to increase the risk that cyclones that do arrive will be category 4 or 5. (This is often misinterpreted, IMO. The decrease in expected frequency is sufficiently large that the absolute number of category 4 and 5 cyclones will also decrease, though their proportion will increase.) In contrast on the West Australian coast, global warming is expected to both increase the frequency and power of cyclones. Overall the effect will be an increase in extreme conditions. IN Queensland we will get fewer cyclones but more and longer droughts, and the floods and cyclones we do get will be bigger. In Western Australia they will get fewer droughts, but more and larger cyclones and floods (except in the South West corner which will get almost permanent drought conditions). You want evidence of this? Reread the thread. I have already provided copious evidence and seen it ignored on a variety of specious reasons. I see no reason to do so again.
78723. Camburn at 13:25 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Norman: What causes rain/tornadoes etc is the temperature differential. At least in the upper midwest of CONUS. To find extrordinary weather events, you have to stick to the changeing of the seasons. One a season has stabalized, the extraordinary events deminish. Climate slueths from NOAA have not as yet found a correlation with present conditions, frequency etc tied to climate change. This may change in the future, but for now it hasn't.
78724. Tom Curtis at 13:13 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       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. Having said that, and for the benefit for anybody else following this thread, it is obvious that a number of factors contribute to weather phenomena. Taking one example, El Nino events lead to hot, dry conditions in Queensland, and that La Nina conditions lead to cold wet conditions. A study such as yours using Queensland data, which did not correlate for ENSO would conclude that specific humidity was negatively correlated with temperature, whereas the opposite is true. The true situation would show up if you sorted the data for ENSO index. Of course, a different pattern arises in New Zealand, so you need to sort for location. In Tasmania, in constrast, ENSO is relatively insignificant but the heaviest rainfall comes in the winter months because the prevailing westerlies shift north in Winter, and blow moist air across Tasmania, whereas in summer they blow mostly south of Tasmania. If you fail to sort for these regional differences in weather patterns, they will introduce a spurious signal into your data. If you use only a small number of stations in a regionally restricted area, they will dominate the signal.
78725. Norman at 13:00 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Tom Curtis, Since you believe my research to be "ridiculous", can you demonstrate empirical data to support your claims that moist warm air is the major ingredient in the formation of severe weather? More warm and moist air will lead to more intense severe weather in the future. You have a model prediction of this. What is the empirical data available currently that would convince someone that this model is a good and valid resource? Again, I am not saying that it would not. I am requesting empirical evidence to support the claim. Thanks.
78726. Norman at 12:54 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Tom Curtis, Here is more evidence of my position. Rather than criticize my research into this (limited by time and access to material). Why not find empirical real world data that supports your view that warm moist air will lead to more severe weather events. Then it would be easier to understand the postition you feel is the correct one. There is a lot of data that does support my current view. Perhaps there is much that supports yours as well. Here is some: Graph of tornadoes in Texas and Oklahoma by month of occurence. Source of above graph link. Oklahoma City climate. I like this web site better than the previous one I was using. It list the rain event per month as well as other data, clouds, sunshine. Oklahoma has the most tornadoes in May, it also has the most rain in that month. But the air is much warmer and has more moisture in July and August yet that is not when the most severe storms occur or the frequency of rain events May is 10 July is 6 and August is 7 (measured at least a trace). If that warm July or August air would be present under May's upper unstable air profile, then I would agree that the moisture and warm air would produce the more severe storms. But I think if you do not take the stability of air into consideration in any argument about severe weather you would greatly miss what is going on. I think stability of air far outweighs moisture and air temp for the production of severe weather and I strongly believe the empirical data available shows this to be the case. A few post up I linked to Missouri river flows and the Mississippi. These are large river basins that cover numerous states. They give a strong indicator of when most the rain falls in these basins. Hint, it is not July or August. The two months with the warmest wettest air that contains the most potential energy. You should answer why doesn't July and August produce the most severe weather. Why do tornado numbers drop sharply in these months? From this source. Alabama Tornadoes. "In the State of Alabama, tornadoes occur most often in the months of March, April, and May." How does your perception of severe weather explain this? Graph of location of Tornadoes in US, check Oklahoma and Texas. Graph of hail location. Graph of monthly tornado frequency. Note it is not July or August, the months with the warmest and most moist air out of the year in the US. Sourc of the above graphs. Climate of Dallas area. Note the May rainfall vs the July rainfall amounts in Dallas Texas.
78727. Paul W at 12:53 PM on 22 July 2011
       OA not OK part 6: Always take the weathering
       Thanks for your extra information. That resolves my question about calcium levels in todays oceans. There is still some un answered questions in my mind. Is the possible change in the pattern of weathering of rocks that occurs with higher CO2 levels in air an allie, enemy or not important? A change in the ratio of calcium silicate and calcium carbonate weathering is a possible positive feedback mechanism. You have focused on carbonate weathering but not silicate weathering. As rain becomes more acid for what ever reason I would expect a change in the ratio of weathering of these two minerals. i would expect more calcium carbonate to dissolve in rain that was more acid. This may not be that simple as land forms also play a role as when the Himalaya's weathered to allow the glacial/interglacial cycle to begin. As silicate precipitation will lead to pH increase which lead to bicarbonate/carbonate level changes it is also a factor. I can't tell if this is significant or not. Is the silicate cycle to some extent connected with the carbonate chemistry in the ocean? The reference (Harvey L.D.D. (2008) Mitigating the atmospheric CO2 increase and ocean acidification by adding limestone powder to upwelling regions.) does point to a limit in the use of ground limestone dissolved in ocean upwelling. It does not deal with dissolution in fresh water rivers or other outfalls which do not face that limit or a preference for silicate over carbonate. As the article points out carbonate is a very inefficient base for changing OA. In aquariums the addition of ground calcium carbonate to raise pH in the short term back fires as the pKa ratios of the dominant buffers have been moved away from 8.3 to 7.6 by the addition and so in the longer term acidification is not remediated. The correct balance of ionic species to give correct pKa (~ 8.3) is needed as well as base to correct aquarium pH not just simple addition of a base to raise pH. (Aquariums become more acid due to nitration and food breakdown products which is different from OA caused by increased CO2 in the air. But the effect of ignoring the existing buffers and there average pKa is interesting) Once a non carbon power source is used a possible method of remediation is less problematic. But as with the aquarium example the correct material will work, other less well designed interventions will just make it worse eventually. Again I'm not wanting to leave room open for fossil fuel use to be justified but to get clearer about possible workable remediation. Our fossil fuel use over the last 150 years has over whelmed the weathering effect that is now much slower. So my interest in speeding up or mimicking weathering comes from that.
78728. KR at 12:49 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Norman - On the one hand, I have to compliment you for taking the time and effort to look into these issues. On the other hand, I have to seriously criticize you for continuing to choose single or several site data sets to discuss global averages. That is just not appropriate, and not informative. In fact, it is (regardless of what those individual sites tell you) cherry-picking, no matter what results you get. I would suggest a different tack for you - look up the global data from someone you might disagree with (look here, for example), see if there are issues or analyses of that data that you find statistically inappropriate, and if you wish then discuss those. 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. 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.
78729. Norman at 12:28 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Tom Curtis, Here is some evidence for you to consider. Revisit a link I sent earlier if you choose. It is about cooling of air in Fairbanks Alaska. Look at figure 2 of article. If you care to look at figure 2 you can see the ground temp drops about 38 C but the air at 4500 meters only drops around 10 C. Air is a really good insulator so the cold air from polar fronts and winter will still remain aloft only slowly warming by non convective processes. Convective events will turn the air at a much faster rate bringing the cold air down to the surface and moving the warmer ground air aloft (spring stroms).
78730. Norman at 12:16 PM on 22 July 2011
       2010 - 2011: Earth's most extreme weather since 1816?
       Tom Curtis # 362 If you have a long record of temperature and precipitation (maybe 100 years) what would geographical or seasonal variables matter? A long series of averages smooths the infomation and takes into account the variables you have listed (like ENSO,AMO,PDO etc). In any given year maybe Kansas City had a May with 2" rainfall and a July with 12" rainfall. But over a hundred years the trend is that May has more rain than July and then you start to look for a reason for this. What is the why? I do not need to gain daily station data or global data...my question is not of a global nature. The question is, is there evidence in the empirical data (100 year or more monthly avearges) that warmer wetter surface air will lead to more severe storms? I am questioning this point. What is more valuable then determining a correlation to temperature, humidity and rainfall from subgroups of data would be to find the mechanism that results in severe weather. You are correct that relatively warm moist air is a necessary ingredient. You need this fuel to power your storms. But you also need unstable air. You can have very moist warm air but if the air above is stable you will not create any storms. Case of point. Omaha Nebraska for the last week. A high pressure dominated the area and not a cloud in the sky. The air was very stable above. The surface air was hot and moist and after cold air moved in Omaha had some nice showers. Now the next question is what makes air unstable. I have posted many links on this mechanism. Unstable air is a situation where you have cooler denser air above warm moist air and an inversion or cap that prevents the warm air from rising into the cold air. Some trigger has to move the warm moist air into the cooler air aloft. (it is like a container of oxygen and hydrogen gas, it is an unstable mixture but can remain in that state indefinately until a trigger occurs such as a spark). You need the cold air aloft or you do not have unstable air. You can get weakly unstable air because of the differential heating between the earth's surface and air above. The property of air as an insulator is why the whole thing works. As spring stroms occur they send latent heat aloft warming that layer and mixing the unstable air making it more stable. The tendency is to make unstable air more stable. So as July and August roll around, the surface air is loaded with energy (heat and moisture) but the air aloft is much more stable and this warmer air will not generate the level of intense storms.
78731. Tom Curtis at 12:10 PM on 22 July 2011
       What we know and what we don't know
       cefarrar @43, in long chain polymers such as petrol, diesel oil, and jet fuel, approximately one molecule of water is produced for every molecule of CO2 in combustion. For natural gas (Methane), two molecules of water are produced for every molecule of CO2. Coal produces effectively no water. Given that the water vapour content of the atmosphere is greater than that of CO2, and the CO2 content has increased by only 0.1% of total atmospheric content, the amount of water vapour added is much less than that. It would have precipitated out and become fairly literally, just a drop in the ocean.
78732. cefarrar at 11:55 AM on 22 July 2011
       What we know and what we don't know
       Does the amount of water produced by the burning of fossil fuels significantly add to the worlds water supply?
78733. muoncounter at 11:45 AM on 22 July 2011
       It's cosmic rays
       pixeldust#49: "it means scientists are being "censored" and "gagged"" Wow, things must be really slow in deniersville. Since when is the very reasonable request made by Heuer, asking a colleague to be 'clear,' rise to the level of 'censorship'? Why not focus on science questions that arise from these supposed 'results'? For example, the PhysicsWorld article dropped what I consider a rather shocking bit: ... the researchers found that this effect also took place when they used a radioactive sodium source, which produces gamma rays, and as such claim that similar measurements in the future will not require expensive accelerators. -- emphasis added Great news! No accelerator needed. But what does it really mean if the 580 MeV (see PhysicsWorld cited above) accelerated electrons that CLOUD used to simulate GCRs and gamma rays from radioactive sodium produce the same effect? It's supposed to require the higher energy of a GCR (100s of MeV to GeVs) to seed clouds. But Na22 produces 0.5 and 1.27 MeV gamma rays; Na24 (formed by neutron bombardment of stable Na23) produces 1.37 and 2.75 MeV gamma rays. What isotope did they use and what energy gammas resulted? If they used low energy gammas from these sodium isotopes, it means that all cosmic radiation, not just the higher energy GCR component should be making clouds! Solar cosmic rays (mostly protons in the solar wind), which give rise to the ubiquitous muon flux we see at the surface should also produce the same effect. Or it means that the whole concept is total bunk. Bet deniers wouldn't like to hear that. Once again, my apologies to Sondheim: But where are the clouds? Send in the clouds. Well, maybe next year.
78734. Christina McGraw at 09:52 AM on 22 July 2011
       OA not OK part 8: 170 to 1
       None of the equations by themselves tell us anything. Our point is that we need to consider all these equations together. In several of the later posts we show how we can use the K and Q values that we have introduced here to know the extent to which each equation occurs and how to work out what the overall outcome is. Read what we say again:

       K for [equation 12] is about 10^-3. That is, the ratio of left to right is about 1,000:1. This means that, to a first approximation, seawater (dominated by HCO₃^-), has only a little bit of CO₂ and CO₃^2-. More importantly, it also shows that if we add CO₂ to seawater, CO₂ will spontaneously react with CO₃^2- to form 2 HCO₃^- because K for the reverse reaction is 10³.

       That is if you reverse the reaction then it still favours, with a 1000:1 ratio the side with HCO₃^- over the side with CO₂. We are unclear how you draw your conclusion about figure 3.
78735. Tom Curtis at 09:50 AM on 22 July 2011
       It's Pacific Decadal Oscillation
       Eric the Red @97, Sphaerica's clarification of his claim should be clear enough, so this is probably redundant, but... You need to distinguish between the popular definition of climate provided by Mark Twain, ie, that climate is what you expect, and weather is what you get; and the formal definition as used by the IPCC:

       "Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization. The relevant quantities are most often surface variables such as temperature, precipitation and wind. Climate in a wider sense is the state, including a statistical description, of the climate system. In various chapters in this report different averaging periods, such as a period of 20 years, are also used."

       Fairly clearly, individual ENSO oscillations do not result in statistically significant changes to the thirty year averages of temperature, precipitation, etc, and hence do not change climate in terms of the formal definition. That is what Sphaerica was claiming. Equally obviously, and for those with the relevant knowledge, an ENSO oscillation does change what we expect to get, and so does change climate for that first, popular definition. However, that change is only due to the advance of our knowledge, and it is dubious to what extent that knowledge has penetrated to the general public. That is why it is just a popular definition, it needs to be indexed to a particular time and population to deliver unambiguous results. Finally, something which changes the frequency of El Ninos to La Ninas, or changes the neutral state to more resemble an El Nino or La Nina state over a multidecadal period would result in a change in climate under the technical definition. On that basis I disagree with Sphaerica's comment about the PDO not effecting climate "without some dramatically magical mechanism", although that sentence is entirely accurate if you substitute "physical" for "magical".
78736. Bob Lacatena at 09:18 AM on 22 July 2011
       It's Pacific Decadal Oscillation
       97, Eric the Red, You need to distinguish between a few very different things: 1) The measured mean global temperature of the ocean surface and the atmosphere (this is not the temperature of the system, but merely what is easy to measure and observe). 2) The amount of energy in the entire "earth" system (which, by proxy, can also represent the total temperature of the entire system) 3) Short term fluctuations in the first item (which represent weather, or, at a stretch, short lived and almost certainly regional climate changes) 4) Long term fluctuations in the actual climate of the earth (meaning changes that represent an actual new equilibrium state) Obviously the difference between 3 and 4 involves some degree of subjectivity, just like the difference between warm and hot is not a precise boundary. But with those four points in mind... ENSO changes number 1, but not number 2, and so is of little interest in anything other than year to year variations. As a result, ENSO also changes only number 3, but not number 4, and so is of no interest in climate changes. PDO is the same. You need to understand the differences here to understand where you are going wrong in focusing any energy at all on something like the PDO. The only things that are actually going to affect the amount of energy in the system are things that cause heat to leave the planet. There are only two ways to get heat off the planet. The first is to heat something up (say, a vat of molten lead) and shoot it into space on a rocket. Obviously, this doesn't happen very often. The second is through radiation. Some mechanism must use radiation to direct energy out of the system and into space. PDO doesn't do that. ENSO doesn't do that (except, as already explained, through slightly increased/decreased radiation, but in the opposite direction of the observed temperature increases). The only things that do affect radiation are albedo (clouds, ice, aerosols) which reflect radiation out before it even heats the planet, or greenhouse gases (which trap radiation in the system) or changes in solar insolation (which increase or decrease the input into the system). PDO can never, ever change climate, and nor can any other fantastical oscillation.
78737. Doug Mackie at 08:50 AM on 22 July 2011
       OA not OK part 6: Always take the weathering
       Supply of calcium is not an issue. [Ca²⁺] is well known and changes negligibly with depth and is roughly 0.010 mol kg^-1. K'_s varies with both temperature and salinity but for example at 35S and 0^oC K'_s for calcite is about 4.3 x10^-7 and for aragonite is about 6.8 x10^-7. Clearly carbonate dominates the solubility of CaCO₃ in the ocean.
78738. Philippe Chantreau at 08:37 AM on 22 July 2011
       It's Pacific Decadal Oscillation
       Spaerica's comment may not have been worded in the best fashion but it is correct. Whatever "cycles" are out there (ENSO, while being an oscillation, does not show clear cyclical bheavior) can only shuffle energy around, they can not create an energy imbalance. ENSO is part of the climate, not a driver of it. It drives weather patterns and affects temperatures on a year to year basis but it is not a forcing.
78739. Eric the Red at 08:04 AM on 22 July 2011
       It's Pacific Decadal Oscillation
       Actually Sphaerica, The El Nino / La Nina cycle does change temperatures by the exact process you describe. When the trade winds are strong, the ocean tropical ocean turnover is greater, exposing more water to evaporation. When the trade winds are weak, the ocean calms, allowing more heat to remain in the ocean. Hence the changing ocean temperature. It has nothing to do with appearance, it is real. ENSO does affect climate, everywhere on this planet. Witness the last few strong El Ninos and La Ninas. You can deny it if you wish, but that will not make it go away. I actually respected your scientific knowledge until your last line. Now it appears you are only interested in your own agenda, and are trying to shout done those who oppose you. So sad.
       Response:

       [DB] It has become transparently clear as to which parties use scientific, peer-reviewed sources based on physics to support their positions versus the hand-waving of those dissemblers who continue to publish their narrative of "It's not Happening/It's Beyond our Understanding/We Must Wait for more Information" without actual understandings or explanations given as to why what we know about the climate system don't actually work the way we observe them to. 

       That, as my child says, is a "tapestry".

78740. Bob Lacatena at 06:22 AM on 22 July 2011
       It's Pacific Decadal Oscillation
       95, Eric the Red, No, you misunderstand. We don't entirely care what drives ENSO (we do, but it's not relevant here) as far as what causes it to happen and to change cycles. What we do care to understand is how the changes in circulation during an El Niño/La Niña event of the ocean expose more or less warm/cold water on the surface, thus raising/cooling global temperatures. We further know that this doesn't actually change the temperature of the planet (except in so far as the planet radiates less heat away during a La Niña and more heat away during an El Niño, so while the planet appears cooler it is losing less heat, and while it appears warmer is is losing more heat). But while ENSO does affect temperature observations, it does not actually affect climate. It can't, and neither can PDO with out some dramatically magical (and understandable and measurable) mechanism. What you are failing to do is to explain how PDO works in any way, let alone how it can possibly (over longer time scales) warm or cool the planet. The bottom line is that only factors which noticeably cause a radiation imbalance (albedo, GHGs, aerosols, clouds) can actually warm or cool the planet. Magical, ill-defined "but what if" oscillations are not science, they're voodoo-magic-superstition.
78741. Bob Lacatena at 06:11 AM on 22 July 2011
       It's cosmic rays
       49, pixelDust, The interview is awfully thin, and only touches on CLOUD for one very brief question. Refer to this post on RealClimate about some other recent, similar research. Basically, in order to build the GCR theory into something remotely respectable, they have to first create all of the building blocks that are similar to an understanding of greenhouse gas theory. In the case of GCR's, they need a precise mechanism, with all of the intermediate steps needed, to show how GCR's actually, mechanically affect cloud formation. Now, his one comment about not interpreting the results probably (I expect) speaks to the fact that the CERN research can only show some very small pieces of the puzzle. They need lots and lots of pieces to compile it into a workable, fully functioning GCR theory. So to over interpret any one step, in either direction, would be foolish. Some of the proposed experiments (to show their level and nature... I took this from some rather old documents on the CLOUD website):
       • We will investigate the clustering of trace gas molecules onto ions. The trace gas molecules will either be formed by the ionising particle beam in pure artificial air or be introduced directly into the chamber.
       • Aerosols of a well defined size and with typical atmospheric composition (NaCl, (NH4)2SO4, H2SO4) can be produced with standard aerosol generation techniques (Section 4.4.3). Experiments will be performed to examine the activation of these aerosols into cloud droplets.
       • These experiments will first quantify the poorly-known production rates of a) nitric oxide (NO) and b) hydroxyl radicals (OH) by cosmic radiation. The former will involve pure artificial air and the latter will involve argon and water vapour. Subsequently we will investigate the effects of these vapours on the nucleation and growth of aerosols.
       • These studies concern the formation of ice nuclei in supercooled vapours at low temperatures. The expansion chamber will be used to create a supercooled cloud by expansion and growth of drops at temperatures below 260 K. ... In addition to experiments with supercooled liquid droplets already present(freezing nucleation),we will also investigate ice nucleation without pre-existing droplets(deposition nucleation).
       • These experiments concern the deposition nucleation of nitric acid and water vapours onto ion clusters to form nitric acid hydrates. Particles composed of such hydrates are thought to be the principal component of the polar stratospheric clouds that initiate the destruction of ozone.
       So, in a nutshell, nothing earth shattering in any direction can come from current CLOUD experiments. They are necessary first baby steps to creating a plausibly complete GCR theory (which in and of itself shows how sicence-fictiony the theory is at its current stage). Which means, in a nutshell, that the deniers are getting their undies all in a bunch over nothing, just because they love to cry wolf conspiracy.
78742. newcrusader at 04:54 AM on 22 July 2011
       Milankovitch Cycles
       Precession can over thousands of years totally change the night sky. For instance in the year 5,000bce, alpha centauri(aka Rigel Kentaurus) was visible from NYC(40N) at that time Thuban was the Pole star in Draco. That star will be visible in NYC again around the year 10,000, at this time Deneb will be the 'pole star' in Cygnus. The March Equinox shifts through all the zodiacal constellations- now in Pisces- it will shift into Aquarius in about 600 years. In the year 3,000 Gamma Cephei will be the pole star.
78743. Karamanski at 03:51 AM on 22 July 2011
       Milankovitch Cycles
       I've been reading about Milankovitch cycles for over a year, and I understand that the Earth's eccentricity oscillates on a 100,000 year cycle, but I still cannot grasp what the 400,000 year eccentricity cycle is and how it affects climate. What is the difference between the 100,000 year eccentricity cycle and the 400,000 year eccentricity cycle?
78744. Paul Magnus at 03:31 AM on 22 July 2011
       Climate Change Denial book now available!
       " Climate change can be solved they say but only when we cease denying its existence." Of course its more than its existence, but also its immensity and dangers and also recognizing the resource, effort and uncomfortable changes to our way of life. Tackling climate change is a life style and mind set change. Its also a moral issue.
78745. Eric the Red at 03:26 AM on 22 July 2011
       Milankovitch Cycles
       Very nice summary Chris. Adding to your answer to Dan's question, the changes in solar radiation occur between perihelion and aphelion, so that ~6.4% more solar insolation reaches Earth in January compared to July. When averaged over the course of the year, the change in solar insolation between high and low eccentricity is small. Currently, the highest solar insolation reaches the Earth during the NH winter. In about 11,500, that will occur during the SH winter. While the amount of radiation reaching the Earth will not change, the amount absorbed will, due to the different albedo of the NH and SH. Many have speculation that this is the cause for the changes in temperature that occur between interglacials.
78746. Eric the Red at 02:39 AM on 22 July 2011
       It's Pacific Decadal Oscillation
       Sky, We know that ENSO is driven by atmospheric pressure variations in the higher latitudes, which determine the strength of the trade winds. The atmospheric pressure changes occur over long time frames, for which an adequate explanation has not been found yet. It is entirely possible that the Pacific Ocean is driving the changes in atmospheric pressure. Therefore, we cannot say whether PDO is driving ENSO (via changes in atmospheric pressure) or is just an index of ENSO.
78747. Chris Colose at 02:26 AM on 22 July 2011
       Milankovitch Cycles
       Here is the Alley graph from the lecture.
78748. Chris Colose at 02:12 AM on 22 July 2011
       Milankovitch Cycles
       Dan, There's two things here: the change in the solar radiation at different points in the orbit (e.g., between aphelion and perihelion) and the mean annual change. With the former, the radiation changes as the inverse square of the distance. So, if you put Earth twice as far from the sun, it would receive four times less sunlight. For an eccentric orbit, the Earth will receive more sunlight when it is a bit closer to the sun than when it is a bit further, which is very intuitive. For the annual-mean solar radiation however, the change that occurs between a circular or a more eccentric orbit is fairly small.
78749. Dan Olner at 02:02 AM on 22 July 2011
       Milankovitch Cycles
       "The modern day eccentricity is 0.016, and as a result, the solar insolation that hits Earth varies by ~6.4% over the course of a year." The thing I'm having trouble with: from wikipedia: "But the mean solar irradiation for the planet changes only slightly for small eccentricity, due to Kepler's second law." So, that's the mean solar irradiation averaged over the whole year that's staying the same? (Because the Earth will be faster when closer to the sun?) Meaning, the irradiance *is* affected by distance at any given moment?
78750. skywatcher at 01:54 AM on 22 July 2011
       It's Pacific Decadal Oscillation
       Eric, you're still making suggestions of PDO driving ENSO without any physical mechanism, or other evidence. There is a proposed mechanism the other way round (ENSO driving PDO), which also makes sense in terms of energy flows and ocean currents. A general question for anyone who knows, what is the sum of all ocean temperature anomalies, both positive and negative, associated with the PDO region? Or how much energy is released/absorbed by the warm/cool segments of the PDO region. As there are large warm anomalies at the same time as cool anomalies, the net influence on global temperature from the PDO region is perhaps less than thought? It would be interesting to see those numbers in relation to the same data for the ENSO region too.

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