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Comments 78801 to 78850:

  1. 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.
  2. 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?)
  3. 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
  4. 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!
  5. 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?
  6. 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. :-)
  7. 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.
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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.
  14. 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.
  15. 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.
  16. 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).
  17. 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.
  18. 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.
  19. 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?
  20. 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.
  21. 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 CO32-. More importantly, it also shows that if we add CO2 to seawater, CO2 will spontaneously react with CO32- 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.
  22. 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".
  23. 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.
  24. 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 0oC 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.
  25. 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.
  26. 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".

  27. 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.
  28. 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.
  29. 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.
  30. 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?
  31. 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.
  32. 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.
  33. 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.
  34. Chris Colose at 02:26 AM on 22 July 2011
    Milankovitch Cycles
    Here is the Alley graph from the lecture.
  35. 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.
  36. 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?
  37. 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.
  38. It's cosmic rays
    Denier sites are all over this recent interview with Rolf-Dieter Heuer, claiming it means scientists are being "censored" and "gagged". Here's the quote in question as rendered by Google Translate: "The results will be published shortly. I asked the colleague to make the results clear, however, not to interpret. This would go immediately into the highly political arena of the climate change debate. One has to be clear that it is the cosmic radiation is only one of many parameters." It's in reference to the CLOUD project's investigations on the influence of cosmic rays on cloud formation. Since his remarks have already become a denier talking point, you might consider addressing them in this article. At the end, you say: "Even if these difficulties can be resolved and the causality link between cosmic rays and cloud formation is proven, this would mean cosmic rays would have been imposing a cooling influence on climate over the last few decades." So for the sake of argument, let's say the latest CLOUD results find that "causality link." Why the "do not interpret" instruction from Heuer? What does it actually mean, in the context of scientific research and publication of results?
  39. Milankovitch Cycles
    Richard Alley shows an amazing figure in his CO2 lecture at 34:03. I couldn't find the one he shows, but here's another from the Petit 1999 Nature paper: The frequency spectrum of the temperature proxies (particularly delta-18 O - bottom left) shows peaks at the periods of the Milankovitch cycles. That makes the connection between the Milankovitch cycles and the glacial cycle, despite the fact the insolation looks nothing like the glacial cycle. The lack of similarity is the clue that the connection is more subtle.
  40. jeff_from_ky at 01:27 AM on 22 July 2011
    Climate Solutions by Rob Painting
    Following the link that CB gave, the calculator is for determining carbon in a single tree. References in the calculator's help screens led me to several sources more useful for my estimates. First, the EPA has a page, Representative Carbon Sequestration Rates and Saturation Periods for Key Agricultural & Forestry Practices, that gives a range of 0.6-2.6 metric tons of carbon per acre per year (for afforestation, which is my particular situation). This in turn led to a paper, Birdsey 1992, Carbon storage and accumulation in United States forest ecosystems which gave good estimates of sequestration rates in my part of the US and my type of forest. The rates applicable to my situation were 1,400-2000 lbs of carbon per acre per year. In an afforestation situation, there is very little carbon capture in the early years, but the rates above are reached in approximately 10 years and will continue for 90-120 years. Using this data, my 10 acres has sequestered at least 70-100 tons of carbon since we started the reforestation and will continue to capture 7 to 10 tons of carbon per year, making a significant reduction in our carbon footprint (currently about 15 tons of carbon per year). Jeff Nelson Paducah, KY
  41. Climate's changed before
    This is somewhat off topic but it seems that whenever the scientific consensus on AGW comes up the reaction of skeptics is to show that there are some outliers that disagree, thus there is no consensus. Consensus does not require 100% agreement. con·sen·sus    1. majority of opinion: The consensus of the group was that they should meet twice a month. 2.general agreement or concord; harmony.
  42. OA not OK part 6: Always take the weathering
    Doug Mackie@16 thank for your thoughts. I agree with you. I would not think of it as a solution but of a nightmare that becomes real at some point. My Ph D topic thirty years ago was hydro treatment of heavy petroleum oils (the clean up step that allows heavy oils to be processed in current refineries). After 6 years I resigned and left that industry not wanting to be part of "baking the planet". I am heartened by the increased numbers opposing the use of fossil fuels particularly the most CO2 intensive alternatives. If I had it my way I'd want coal use to stop ASAP and other fossil fuels to only be used if carbon was put into the ground to match their extraction. Discussion of the needed geo-engineering required to return the planet to below 350 ppm CO2 in air is sobering as it is an extreme task as you rightly point out. I do expect that we will be forced to it (for a very long time) if politics don't change promptly. The discussion of what recovery processes will be needed for the ocean is also sobering. Since aragonite life forms are possibly the most vulnerable, the chemistry of ocean remediation is interesting. There is a slight reduction in the volume of calcium silicate over carbonate needed but it's still profoundly large. James Hansen made a quick reference to grinding igneous rocks in a talk. I've also been considering the work ability of it. You have been focusing on carbonate chemistry but the other part of the calcium carbonate solubility product calcium ions is worth a mention. In my readings so far I have not seen any discussion of Ca2+ concentrations. (I've not yet been looking for it) I wonder what the historical ocean Ca2+ concentrations have been over deep time. I've been curious about the [Ca2+] levels at paleo thermal maximums. I appreciate your work on this topic by the way. OA has been under discussed and is very concerning.
  43. Eric the Red at 00:54 AM on 22 July 2011
    It's Pacific Decadal Oscillation
    Dikran, I do not think that anyone is doubting physics here. The contention was whether the PDO drives, or is simply a measure of ENSO variations. Considering that ENSO has been shown to influence temperature, then if PDO is causing the ENSO variation, then it logically, influences temperature. If PDO is simply an index of ENSO, it will indirectly influence temperature through ENSO variation. However, in this case, it would be better to use ENSO as Tamino an others have done. Pointing out correlations is indeed science, as it leads to experiments resulting in greater understanding of the correlation (or rejection thereof). To dismiss such a correlation without investigation, is not science.
  44. Dikran Marsupial at 00:36 AM on 22 July 2011
    It's Pacific Decadal Oscillation
    Eric the Red wrote: "As mentioned, whether PDO drives ENSO variations or is just an index of ENSO changes deos not matter to its temperature influence. " That is incorrect. If PDO is merely an index of ENSO, then the effects of PDO on temperature is precisely zero conditional on measurements of ENSO. Secondly if PDO is merely an index of ENSO then it is a bad idea to make projections of future climate based on PDO as it may not have any physical significance at all. There is also the point that PDO may measure the effect of changes in climate on ENSO rather than the other way round. The warming of the early 20th century is explainable by changes in solar forcing. The Pacific ocean has a large surface area and a low albedo, so it will have absorbed a fair bit of extra energy over that period. Is it inconceivable that might have had an effect on ENSO, causing the PDO? We all know that ENSO is a factor, and we have physics that can explain the magnitude of the effect, as ENSO is reproduced in modern AOGCMs. Continually pointing out correllations without a physical mechanism that can explain the strenght of the effect is not science, is fine, but it is not a good reason to doubt solid physics.
  45. Eric the Red at 00:26 AM on 22 July 2011
    Sea level rise is exaggerated
    You may be interested in this paper, if not for the specifics of the Australian measurements, for the international references. http://www.jcronline.org/doi/full/10.2112/JCOASTRES-D-10-00141.1
  46. Eric the Red at 00:14 AM on 22 July 2011
    Climate's changed before
    Tom, To what consensus are you referring? If you mean that temperature have risen globally or that atmospheric CO2 has increased, then yes. But, if you are referring to how much CO2 has contributed to the observed warming, and how much warming we can expect in the future, then I am afraid we have a long way to go to reach a consensus. Predictions have been all over the board, however as any fortune teller or stock broker will say, "make enough predictions, and some will come true."
    Moderator Response: [Dikran Marsupial] Actually the world climatologists are in pretty good agreement about the contribution of the CO2 to the observed warming etc. You may disagree with this, however it is for you to provide evidence to back up your opinion.

    Secondly the projections have not been "all over the board"; the uncertainties of the projections are high; that is not the same thing.

    Now this part of the thread seems to be heading to a point where no progress is likely to be made, and posts become indistiguishable from trolling. So unless you want to provide an evidence based argument with references to sources backing up your position, I suggest we all move onto a more substantive issue.
  47. Eric the Red at 00:08 AM on 22 July 2011
    It's Pacific Decadal Oscillation
    As mentioned, whether PDO drives ENSO variations or is just an index of ENSO changes deos not matter to its temperature influence. Yes, it would be nice to understand what causes these fluctuation, but as long as we can measure the response, we can attribute the effects on the temperature record. The PDO was positive from 1977 - 1998, and could have contributed to the obserbed warming during that period. For the next decade, it oscillated around 0 until around 2008, when it turned negative. Compare the following graph to temperature graphs. http://en.wikipedia.org/wiki/File:PDO.svg The fact that Tamino can correlate temperatures to ENSO (or PDO) should indicate that it is a factor. How great a factor is still under investigation.
  48. Stephen Baines at 23:55 PM on 21 July 2011
    It's Pacific Decadal Oscillation
    The poodlebites...A recent paper on global SO2 emissions 1850-2005. The US and european emissions have declined since the early 80s due to cap and trade, but China and other developing areas have been increasing exponentially, making up the difference. SO2 emissions have varied between 110 and 130 Gg/year since about 1960.
  49. It's Pacific Decadal Oscillation
    #88: Surely if, given that the most likely causal relationship is that ENSO drives PDO and not vice versa, we are likely to see more 'negative' PDO state if we have more frequent La Ninas? So your last sentence is in effect backwards. As ENSO is already factored into climate attribution (most recently and most neatly by Tamino), there is no great mystery, at least in relation to PDO. I prefer PDV, with V for variation, as there is no demonstrated cyclic pattern; additionally the 'cool' part of the variation has large positive heat anomalies in the central North and south Pacific.
  50. thepoodlebites at 22:30 PM on 21 July 2011
    It's Pacific Decadal Oscillation
    #87 Tom Curtis Do you have a cite for variations in anthropogenic SO4? The EPA shows that U.S. trends in SO2 have been decreasing since 1981. And SO4 concentrations are linearly correlated to SO2. Here's a good website for PDO. The PDO has been more negative than positive since 1998 and could account for some of the pause in surface temperature increase in the last decade. Since global temps are tracking scenario C the best, the pause can not be related to CO2 emissions, CO2 emissions have not stopped since 2000. If the negative PDO trend continues, we should see a shift from more El Ninos (80's, 90's) to more La Ninas (00's, 10's?).

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