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Comments 73901 to 73950:

  1. Pielke Sr. Agrees with SkS on Reducing Carbon Emissions
    As a laymen I have been following the exchange between Dr. Pielke and this site very closely. Dr. Pielke is someone that understands the physics, (-Ideology snipped-) and agrees with points of view espoused here, and yet comes to different conclusions. I did not see any credible refutation of his work here, simple disagreement with his conclusions. (-Inflammatory snipped-). He made the claim that man-made CO2 was responsible for about 26% of the yearly global emissions. I did not see any refutation of this claim. He also stated there were many other factors affecting climate irrespective of CO2 alone; Again, I did not see any credible refutation of this position. "Global warming or cooling involves changes in Joules of heat in the climate system. This involves changes in heat in the oceans, land, atmosphere and cryosphere. As concluded by Jim Hansen and others, the ocean is by far the component of the climate system where the large majority of this heating and cooling occurs. Receding ice, surface temperature, atmospheric temperatures make up only a relatively small portion of global warming and cooling." If you feel ignoring other aspects of the climate while elevating CO2 to a greater position of authority, there is not much one can do, but this does not ultimately make the scientific case. You may have proven that CO2 is a GHG, but you have not proven that it is the primary driver of climate overcoming all other factors. As Einstein states: "No amount of experimentation can ever prove me right; a single experiment can prove me wrong." - -- Albert Einstein
    Response:

    [DB] Ideological insinuations of fraud snipped.  And do please try harder to be less inflammatory.

    AFA Einstein: he said many a thing.  My favorite by far:

    Any man who can drive safely while kissing a woman is simply not giving the kiss the attention it deserves.

  2. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Sphaerica#47, Ha! There is documentary evidence. No trend though. At least no one will blame this on cosmic rays. Sorry, upon closer inspection, there do not appear to be any dogs involved. Just raining cats and pitchforks.
  3. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    45, muoncounter, I've done an extensive search of the literature, and can find no definitive link between climate change and feline-canine precipitation. I'm afraid this is just evidence of more unsubstantiated alarmism on your part.
  4. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    muoncounter, exactly! Particular types of weather events lend themselves to generating unusual or extreme weather. 'Blocking' patterns are one of those kinds of weather events, that can lead to prolonged dry or wet in particular regions. Except now, blocking events are often leading to 'extreme', rather than just 'unusual'. Extremes that are as you would expect with a warmer atmosphere that can hold more water vapour. And Norman's wrong, it's very obvious that the intensity of this year's Texas drought and summer heatwave has not happened before, shown by you in John N-G's graph (#21). His response was to say "look at the annual temperatures", an obvious diversionary tactic from the uncomfortable fact of this year's heat and dry in Texas' summer, part of a summer trend, shown by Tamino.
  5. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    skywatcher#44: "a link between blocking, extreme weather and climate change. " How could there not be a link? We've had this back and forth before. 'Blocking' is a weather pattern; saying 'this drought is caused by blocking' is a bit like saying 'it's a drought because there hasn't been any rain.' But no blocking system has been in place for a year, as indicated by the map here. Norman's thesis appears to be 'yeah, but this has all happened before.' 'This' being drought, heatwave, flooding, windstorms, tornadoes, etc. Until it literally starts raining cats and dogs, he's right. Its just that the list of 'yeah, buts' keeps getting longer.
  6. Lessons from Past Climate Predictions: IPCC AR4 (update)
    I'm very disappointed by the standard of arguments by Carrick, Lucia, Charlie and others. They've been unable to suggest anything other than cherry-picking reasons for changing the 2000 start date. They've been unable to pick any good reason why not to use GISS, other than empty suggestions of deception. Most importantly, they've been unable to indicate why Dana's conclusions are incorrect. Given the neutral-negative ENSO and negative solar forcing over that period, global temperatures are just where you would rationally expect them to be, slightly below model projections, even if you use the non-global NCDC or HADCRUT products. If the critics can't actually show that this post's conclusions are in error, they're left with empty nit-picking, and really, is that all they have?
  7. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman, refer back to John Nielson-Gammon's graph. Would you call 2011 'normal' for Texas. It's set new records for temperature as well as drought, and is far from the previous distribution of such events. See Tamino's take on it as well. While annual Texas temperatures may not have much trend, summer temperatures do. Which ones do you think matter more for extremes? It reminds me of the way that in the UK, we had the hottest April ever, beating the previous clear record-holder, 2007, into second-place. Remember that? Thought not. Of course, in UK April hot dry weather means nothing more than some pleasant evenings and a few (occasionally quite damaging) wildfires. It's not headline-making in the way that the large amounts of snow in the last few winters (without significant temperature records) has been, and it's not a headline-making record-breaking heatwave like the same weather in July would inevitably cause. It's still extreme weather. A lot of British weather opinion has been linked to the perceived cold wet summers (I think I would agree with that for the last five years or so), and the extreme snowfalls. Less has been made of the extreme floods that we've seen (e.g. Cumbria and Gloucestershire), or the general patterns of extreme precipitation. I remain interested in the link between reduced Arctic sea ice and early winter snowfalls - if true we should see more of that. Extremes come in many guises, but they are not very likely unless something is forcing the climate system out of its normal state. In the UK and worldwide we're seeing a lot of extremes. Norman, as an aside, an interesting link between blocking events and global warming comes from Stu Ostro (very large presentation), but then I've linked that to you before. He sees a link between blocking, extreme weather and climate change.
  8. Galactic cosmic rays: Backing the wrong horse
    muoncounter 21 OK I got it slightly wrong. Here is a quote from the Svensmark paper: "To further investigate the time-scale to produce a charged critical cluster, an electric ‘clearing’ field has been used. Applying an electric field of, for example, 600 V/m reduces the small ion life time to seconds, thus decreasing the time available for the ions to participate in nucleation. However, this did not have any effect on the nucleation process, and only at much larger electric field strengths did a significant response become apparent. For field strengths up to 6000 V/m, the particle production was reduced by ca 20% and at larger fields up to the current maximum of 12 000 V/m, the particle production was reduced by ca 50%. Since, as stated earlier, ions are involved in almost all particles produced, this indicates that the characteristic time for producing a stable cluster is very short, i.e. 2 s or less" (-Snip-)
    Response:

    [DB] Inflammatory deleted.  Please refresh yourself with the Comments Policy and ensure that future comments fully comply with it.

  9. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    muoncounter @42 From your Jeff Masters link. Link to graph of Texas March drought index. If you look at this graph you can see about 8 years that were exceptional droughts (-4) before 1960 and there were none after 1960 except for this year. Around 1920 you had one year that was a drought in the -6 level and a few years later it was above 6+. From the drought index chart it would seem that there are very few years that are normal. Normal is a data point between extremes.
  10. Galactic cosmic rays: Backing the wrong horse
    granted... I thought someone needed a reminder.-
  11. Pielke Sr. Agrees with SkS on Reducing Carbon Emissions
    @ Chris G., #3: I would guess that the (somewhat cynical) "iron law" holds in normal times. However, in times of crisis, I believe the iron bends. For instance, what was the economic advantage to passing the laws that were responsive to the Civil Rights movement? It's very possible that there will not be any effective laws passed until the economic harm is more visible. I refer to: http://www.doonesbury.com/strip/archive/2011/09/25
  12. Galactic cosmic rays: Backing the wrong horse
    Dave123#23: "a number hurdles to jump" Those were among the key points of the prior 'Saying nothing' thread. What I wanted to do here was demonstrate that even putting aside all those hurdles, the record is this: We've seen events (like the Jan 20 2005 GLE) that should have done the job -- and they did not. That horse was scratched from this race.
  13. Galactic cosmic rays: Backing the wrong horse
    It seems to me that cosmic ray afficiandos have a number hurdles to jump: 1) showing that in the atmosphere other mechanisms for cloud nucleation are insufficient to account for cloud formation. Given the enormous amount of anthropengenic dust, nitrogen oxides etc have come to reside in the atmosphere this seems more than a little challenge. What evidence is there that supersaturated air masses do not form clouds with great ease? 2) Showing that there has been some (any) variation in cosmic ray flux coincident with the rise in GMST. Not hypotheses about how it might occur....real data here. 3) Overturning the physics of CO2 and showing why every calculation has been overstating the direct forcing from its increasing levels in the atmosphere. This will also require an explanation of the CO2 signature in TOA emissions and back emissions to the earth.
  14. Galactic cosmic rays: Backing the wrong horse
    tblakeslee...Arguing about the behavior of muons with someone whose alias is "muoncounter" is the equivalent of spitting into the solar wind. I would advise against it. To quote from the Laken et al 2010 paper you linked to. "This work has demonstrated the presence of a small but statistically significant influence of GCRs on Earth’s atmosphere over mid-latitude regions." and "The climatic forcings resulting from such solar – terrestrial links may have had a significant impact on climate prior to the onset of anthropogenic warming, accounting for the presence of solar cycle relationships detectable in palaeoclimatic records." So the authors doing active research and promoting this idea see this as a small effect possibly contributing to past variation, but not to current warming. As I said before, it'd be cool if it panned out, though it's unlikely to for all the reasons mc has mentioned. Even if it does pan out, it will allow us to account for more short term natural variability, which will only make the effects of anthropogenic GHGs more obvious. This whole debate sounds like a disguised version of the fallacy that climate scientists think that only GHGs affect climate.
  15. Pielke Sr. Agrees with SkS on Reducing Carbon Emissions
    One proofread too little: Dr. Hansen... _where_ he attempts... ...favored energy sources will _be enacted_ until...
  16. SkS Responses to Pielke Sr. Questions
    Re: #184 "Moderator Response: [John Hartz] Thanks for the nice words. Like elephants in the circus, all SkS authors, including Dana, work for peanuts. Every so often, John Cook pops in to fill up our bowls and sweep up the shells." Correct except in one point: There are no peanuts, and therefore there are no bowls.
    Response:

    [DB] Actually, I get comped in beer futures...

  17. Pielke Sr. Agrees with SkS on Reducing Carbon Emissions
    The points of agreement are interesting; the points of disagreement should be equally so. What I gathered from this discussion was that Dr Pielke does not disagree that CO2 is a substantial forcing, but simply believes that it does not contribute to climate change such a large proportion of the forcings that it should be acted upon in isolation. Dr Hansen has published papers when he attempts to estimate how much CO2, aerosols, land use, and other factors contribute. I'm not sure if Dr Pielke has made similar estimates, but I'd be interested in them if they exist. What I'm coming around to is that there are always tradeoffs to be made in any course of action to be followed, and the way to decide the course to follow is to focus most of your efforts on the actions with the best cost/benefit ratios. To the best of my knowledge, reducing CO2 emissions still gives of the most bang for the buck. (Is that a local colloquialism or is it more widely understood?) If you can't get the leaders of the major industrial powers to agree to some plan for reducing emissions, I don't know how you would go about trying to convince millions of individuals in growing populations to quit converting forest to farmland, just for example. I probably won't read The Climate Fix: What Scientists and Politicians Won't Tell You About Global Warming because the subtitle hints strongly at conspiracy and subterfuge, and that turns me off. So, I should not comment, but I will anyway, but this is just based on a skim of comments and reviews. The "iron law" to the effect that if economics and environmental issues come head to head, economics wins, has some merit, but this is a matter of public perception. When a river catches fire because of the all the pollutants in it, the public perceives that maybe they are better off with some pollution regulation rather than purely capitalistic industrialism. It would be naive to think that fossil fuel corporations are not aware of this, which is why, in the US, we see advertisements about how coal is clean, natural gas fracking is safe, and tar sand oil is secure. It would also be naive to think that major industrial powers don't have influence on governing bodies, and naive as well to think that corporations producing fossil fuels will not recognize the advancement of alternative energy sources as a threat. So, I have little faith that laws and regulations which change the balance of favored energy sources will change until there is public outcry, at least not in the democratic countries. Based on the material I've read, I believe these critiques apply to the main gist of the book, but I'll stand corrected if someone points out otherwise. P.S. Yes, I am aware of the irony/hypocrisy that I won't read the book because of the implied subterfuge, and that is exactly what I'm saying is happening. I'm not proud; I can handle it.
  18. Galactic cosmic rays: Backing the wrong horse
    tblakeslee#20: "using natural muons and essentially turning them off with a strong electric field." That must've been some electric field, as natural muons reach the surface with an average energy of 3-4 GeV (that's G as in billion). SKY used 580 MeV electrons; CLOUD uses 3.5 GeVs. So here's a puzzle: 'Natural muons' are largely a product of solar wind protons. If they are so good at making clouds, why doesn't cloud production (and the cooling or warming that is supposed to result) more closely match the solar wind output? Another puzzle came to light here: electrons, like cosmic rays in the real atmosphere, are ionizing molecules in the air and so cause water molecules to stick together. Furthermore, the researchers found that this effect also took place when they used a radioactive sodium source, which produces gamma rays The basis of Svensmarkism is that solar variation modulates cosmic ray flux and thus cloud production. If natural gammas are of sufficient energy to ionize and thus are also producers of clouds, how can the interplanetary magnetic field be relevant to that process? Gamma rays aren't touched by magnetic fields. And thanks for the cloud chamber reference. Demonstrating a 'principle' in a closed chamber is nowhere near as difficult as demonstrating that the mechanism is viable in the atmosphere.
  19. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman#41: "some meteorlogist took the time and made such graphs of other locations would it look much different?" Short answer, yes. Look again at this graph. Then look at this map: That's a twelve month period with precipitation below 60% of a 50 year average. We're way out of normal bounds here. Not the new normal? That is a measurable event, based on 30 year averages -- in other words, a climate change. Look back at any of our extreme weather threads; read just the April recap of Jeff Masters' blog. I've suggested this before: keep a list of the number of things you have to explain away as 'a normal event.' Or you can content yourself with the warm feeling that all we ever see is weather and thus climate change is always Mañana.
  20. Galactic cosmic rays: Backing the wrong horse
    muoncounter "not duplicating/confirming Svensmark" Why change my words and then disagree? I said it was "a confirmation and refinement." The SKY experiment was done in frustration because the CLOUD experiment was delayed by over a decade. It was done inexpensively by using natural muons and essentially turning them off with a strong electric field. Here is the link: http://www.space.dtu.dk/upload/institutter/space/forskning/05_afdelinger/sun-climate/full_text_publications/svensmark_prsa_oct2006.pdf Actually you can buy your own Wilson cloud chamber kit for $23 which will demonstrate the principle nicely. Natural muons from space will leave clear tracks in the supersaturated vapor clearly demonstrating how cosmic rays can produce clouds.
    Moderator Response: [Dikran Marsupial] Paraphrsing is perfectly acceptable unless quotes are used to suggest it was what you actually said. Please, no more of this sort of pointless bickering, please stick to the substantive issues.
  21. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    muoncounter @37 I will post the link again for ease. (it is also at post 15). Historical Texas climate. Look at the Texas annual precipitation graph. Any one season can be extreme and has been. Look at the preciptiation for Texas in 1917. It is several inches below the normal. Then two years later it is several inches above the normal. The severe weather phenomena makes me think of selective perception. Looking at the highly varialbe nature of temperature and precipitation in the state of Texas over a 100 year period, I think it would be a safe assumption to expect this of any location. So if the globe is your area of selection, you will certainly be able to find extreme events in some location on the globe every year. Looking at Texas overall I can't see any clear link that precipitation or temperature of the last decade are anywhere outside the long term events. If some meteorlogist took the time and made such graphs of other locations would it look much different? If Texas data is a sample of what goes on around the globe, from the available graphs I can't see how anyone could conclude "global weirding" or "the new normal" Look at the preciptiation amounts before 1960 and after and please explain where is the evidence Texas droughts are getting worse?
  22. Ocean Heat Content And The Importance Of The Deep Ocean
    Chris @ 24. To quote from the Shaviv paper I referenced, "we use the oceans as a calorimeter to measure the radiative forcing variations associated with the solar cycle. This is achieved through the study of three independent records, the net heat flux into the oceans over 5 decades, the sea level change rate based on tide gauge records over the 20th century, and the sea surface temperature variations. Each of the records can be used to consistently derive the same oceanic heat flux. We find that the total radiative forcing associated with solar cycles variations is about 5 to 7 times larger than just those associated with the TSI variations.." The tidal data is only one of three methods that gave impressive and consistent results. Tides vary significantly from place to place due to the a magnification of the tidal wave by the shape off the ocean bottom. Averaging over the planet or even over nearby areas makes no sense as the shape of the ocean bottom varies. The more abrupt the change in gravitational pull, the greater the magnification. An 11 year cycle has no such effect as the change is so slow that no wave is formed. Dismissing this entire paper over this questionable objection on one of the three methods used shows a strong need to ignore this elephant under the rug.
  23. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Schaerica #35 Good point, I am considering buying and reading the book at this time after your post. Maybe it will answer the questions I have.
  24. Ocean Heat Content And The Importance Of The Deep Ocean
    Climate sensitivity to Milankovich forcings -- an order of magnitude smaller than the forcings due to increasing GHGs -- melted mile thick glaciers from the Arctic to mid-latitude North America and Europe. In around 4000 years. So, does the climate show high or low sensitivity to change? Sounds damn sensitive to me. With less ice to melt in mid-latitudes it sounds to me like there will be more energy to do pernicious things to agriculture. The activity that 7,000,000,000 of us depend upon for food.
  25. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Anne-Marie Blackburn @38, In my post to muoncounter at #33 I link to an artice that does go into the effect of Global Warming on the Texas drought. His conclusion is about 0.9F of the total 5.4F above normal for the Texas summer.
  26. Lessons from Past Climate Predictions: IPCC AR4 (update)
    Matthew @99: 1) You are projecting temperatures with a linear trend, so of course your projections understate IPCC projections. 2) Taking a 5 year mean at the start and the end of a period is not an accurate method of determining a linear trend in any event. Mathematically, therefore, you cannot do what you purport to do (find a trend) with the methods you use. 3) If you take a five year mean, the value arrived at is the value for the median year of the mean. Consequently when you take a 2006-2010 mean, you determine a value for 2008, not 2010 as you suppose. 4) Most importantly, El Nino's and La Nina's do not neatly alternate. Sometimes, as for example 2002-2007, you get a string of El Nino's with only neutral conditions or weak La Nina's (2006) intervening. Nor are all ENSO fluctuations of equal strength. The 1997/1998 El Nino was particularly strong, while the following 1999-2001 La Nina episodes were moderate. Consequently a simple five year mean will not eliminate ENSO effects from the data. For example, a 5 year mean centered on 2000 would include a strong El Nino year, 2 moderate and a weak La Nina, and a moderate El Nino, probably resulting in a slightly positive (El Nino) average. A five year mean ending with 2011 will include a moderate, a strong and a very strong La Nina and two moderate El Nino's, probably being net negative as a result. As noted @ 23, Tamino has already produced temperature indices adjusted for ENSO, vulcanism, and solar variation. The result shows a 0.17 degree per decade warming, just shy of the 0.18 projected by the AR4 A2 multi-model mean. That is certainly well within error.
  27. Anne-Marie Blackburn at 22:13 PM on 25 September 2011
    Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman One thing I find interesting about your approach to the possible link between climate change and extreme weather is the very narrow way in which you think climate change can affect extreme weather. You say that many extreme events are caused by blocking events. This is correct, but many are not linked to blocking events. So I really don't think is a valid premise to start with, and I've not seen any scientist claim that this is the only way to determine the link we're trying to establish. Also, let's say, hypothetically, that a blocking event is purely natural in cause, how can you show that greater temperatures or water vapour levels brought on by climate change are not going to have an impact on a drought or flood caused by that blocking event, for example? What mechanism do you suggest nullifies the role of climate change in extreme weather when a blocking event is involved?
  28. Lessons from Past Climate Predictions: IPCC AR4 (update)
    It looks like Carrick has joined Lucia and the others on this thread who cannot criticize the conclusion of the post so they make up unsupportable accusations of cherry picking to distract readers. The conclusion of the post is: the IPCC projections match the last 5 years of temperature reasonably well but are a little low (within the error bars). If you contest the conclusion please present a correct graph that shows the conclusion is in error (make sure that you have not cherry picked the start time). {snip} Carrick: please use at least 30 years of data to compare temperature trend records (your data only covers 20 years)or people will think you are cherry picking. You will find your differences mostly go away. Why did you make such a transparent argument here? {snip}
    Moderator Response: [grypo] Please, take it easy on the inflammatory language and insinuations. Thanks!
  29. Lessons from Past Climate Predictions: IPCC AR4 (update)
    So I figured out a smoothing avg of 5 years on a 1980-1999 baseline for giss data to remove the enso... Here is what I got... 1987-1991 is avged to .02c 2006-2010 is avged at .316c 20 year equation for 1990-2010 is f(x)=.0148x+.02 f(20)=.0148(20)+.02 f(20)=.316c check! f(30)=.0148(20)+.02 f(30)=.464c for 2020 f(40)=.0148(30)+.02 f(40)=.612c for 2030 The ten year trend for 2000-2010 is (0,.164)(10,.316) equation f(x)=.0152x+.164 f(x)=.0152(10)+.164 f(x)=.316 checks! for 2010 f(20)=.0152(20)+.164 f(20)=.468c for 2020 f(30)=.0152(30)+.164 f(30)=.64c by 2030 So yes it is quite a bit off the models here they are year A1b1, A2 2010 .408, .423 2020 .684, .615 2030 .944, .809 I did a smoothing of 5 years with the new maps to get the means...>1987-1991(.02c), 1997-2001(.164), 2006-2010(.316), each one of these have nino's and nina's. Had to as there is no map of the giss at 1980-1999 baseline. I put together a 20 year equation from 1990-2010 and worked it out to 2020, 2030.
    Response:

    [DB] Your link is broken to your graphic.

  30. Ocean Heat Content And The Importance Of The Deep Ocean
    Mlyle @ 11 - the average depth of the ocean is 4300 mtrs according to NOAA. See hyper-link provided in the post. CharlieA @ 12 - Figures 1 &2 are from the model runs. Wingding @ 16 & 17 - One only has to look back over the last half-dozen decades to see that the slowdown in the 700 mtr ocean surface layer is not unprecedented - in fact greater than decade-long slowdowns have occurred. See Levitus (2009). In other words what we're probably looking at is natural variability. Periods of little upper ocean warming balanced against periods of large upper ocean warming. Again this is evident in the observational record of the 20th Century. Dean @18 - The idea is that: if the upper ocean has a limited capacity for warming, and being the principal source of atmospheric warming (covering around 70% of Earth's surface) how can the atmosphere continue to warm? All very hypothetical of course. Paul Magnus @ 21 - global warming has already seen an increase in the intensity/frequency of La Nina/El Nino in the 20th century. What lies ahead is uncertain - the models don't seem to agree. Heat (as in longwave radiation) doesn't warm the upper ocean. The surface ocean is warmed by solar radiation, which loses heat to the cooler atmosphere above, thus making surface atmospheric temperatures warmer. Increased greenhouse gases change the relationship by warming the top of the ocean 'cool skin' layer. This lowers the temperature gradient in the skin layer resulting in less heat escaping to the atmosphere, and causing the ocean to steadily accumulate heat. I've written a post on this topic, which should be published soon after the post on Meehl (2011).
  31. Galactic cosmic rays: Backing the wrong horse
    The start is much better Muon. The reason I raised it is because a lot of people are not aware of the experiment and the issues it has raised. To a 'novice' the initial paragraph may have been confusing.
  32. Lessons from Past Climate Predictions: IPCC AR4 (update)
    Garrick @94 again suggest that Dana has been guilty of cherry picking. It is a rather bizzare accusation given that Dana started with his comparison with the first year of the projection. Of course, as those who make it know very well, in short trends, changing the start of finish date by a year can make a large difference. They know, in fact that shifting the start date back a year will make a difference to the trend. That makes the accusation worth looking at closely. Carrick claims that Dana's start year is an outlier, and it is indeed cooler than any other year in the 2000-2011 period. There is a reason for that - it was a moderate La Nina year. Of course, 2011 was also an outlier in that respect. Indeed, the first months of 2011 (and hence Dana's end point) was the strongest La Nina in over thirty years. I'm pretty sure Carrick knows that too, but you don't see him insisting that Dana finish his trend analysis in December 2010 because 2011 is an outlier. It is only cool periods early in the trend that Carrick believes should be expunged from the analysis. You can see what is going on in this detail of the Multivariate ENSO Index: Delaying the start point of the analysis until one year after the start of the projection shifts us from a moderate La Nina to neutral (but slightly cool) conditions). It would make a very large difference in a plot of the MEI trend, both by shortening the interval and by raising the start point. It would also make a difference to the temperature trend. But excluding 2000 as a start date because doing so will give a flatter trend is cherry picking. In fact, the suggestion of a 2001 start date is not the only one that has been suggested by Lucia, Carrick and cohorts. Suggestions have even been made that 2004 (a moderate El Nino) should have been chosen as a start date. Indeed, even more bizzarely, Lucia has even suggested that running the trend to the most recent date available is also grounds for an accusation of cherry picking. Apparently, in order to be absolutely free of any taint of Cherry-Picking according to Lucia's rabble, Dana needed to start the trend between 2001 and 2004, and finish it in a strong La Nina year (2011 if you must, but 2008 by preference). In simple terms, in order to avoid accusations of cherry picking by Lucia's rabble, Dana needed to deliberately cherry pick for a low trend.
  33. Lessons from Past Climate Predictions: IPCC AR4 (update)
    Carrick @90, contrary to your claim, the NCDC does not include data north of approximately 80 degrees North, or south of 60 degrees South (except for a few isolated stations). This can be seen clearly on this plot of the temperature anomaly for March 2011 (chosen because it has a minimum number of 0 degree anomalies to confuse the issue of coverage). (Clicking on the image links to the NCDC so you can compare multiple graphs). I have also downloaded the ncdc_blended_merg53v3b.dat file and confirmed directly that the relevant cells are in fact missing. So my original claim that both Hadcrut and NCDC do not show polar regions stands. NCDC is preferable to HadCRUt in that it at least shows remote locations in South America, Africa, Australia, Siberia and the Canadian Arctic, unlike Hadcrut. Never-the-less, gistemp remains superior in coverage to both its rivals. In your follow up you suggest comparing DMI and gisemp. I have already shown one such comparison in my 23. Based on that comparison, gistemp is running cool in the Arctic.
  34. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman#34: "stating extreme weather events are like loaded dice is an incorrect view" Norman, its a metaphor. When the expected range is 2-12 and 13s start popping up, the dice aren't loaded; there's a die with a 7 on it. Dr. Tobis says this best: A truly bizarre season occurs in a particular place. Either these extraordinary events are connected, which is perhaps unlikely, or they are unconnected, which is extremely unlikely. That is, you are asking for a bizarre coincidence. But now we add up the number of bizarre coincidences, for each of which John [Nielson-Gammon] can make comparable arguments. The tornado outbreak this spring. The huge blocking event in Asia last summer which did so much damage in central Russia, Pakistan, and parts of China. The fires in Australia in 2009 and the floods this year. The floods in the midwest. Heat waves in Europe. None of these are clearly part of local trends. None of these are particularly predicted in the literature, and as far as I know the GCMs don't indicate these things happening. But, here's the thing. They are happening.
  35. Lessons from Past Climate Predictions: IPCC AR4 (update)
    Carrick, as DB suggests, please tone it down. I don't see why we can't have a civil discussion without becoming so abrasive. As we already discussed on Lucia's blog, choosing 2000 as the start date for the analysis was not "a mistake", nor was it a cherrypick. That's the year that the IPCC AR4 began running its models. To exclude the first year of the model run, as you suggest, would be a cherrypick. And to exclude any available data when we're only looking at 11 years' worth or so would be unwise. Removing the effects of ENSO is another possible approach, but an incomplete one. What about solar effects? And AMO? And volcanoes? And anthropogenic aerosols? If you're going to start filtering out short-term effects, you need to filter them all out, and that's a major undertaking. The point of this post, as in most of the 'Lessons' series, is merely to get an idea about how well model projections and data have matched up to this point. As I noted in the post, there's really not enough data since the AR4 to make any concrete conclusions. If you disagree with my approach, you're free to do the analysis however you'd like on your own blog. But if you're going to keep posting here, please take the time to read our comments policy. This isn't Lucia's or Watts' or Bishop Hill's blog. Accusations of deception and inflammatory tones are not allowed here. Please keep it clean.
  36. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    I don't have a Kindle or Kindle SW. Has anyone used Kindle SW on a Mac or PC and found it useable and useful?
    Moderator Response:

    [DB] I use my Kindle to store PDFs of science papers from my PC.  Works well for travel and camping trips.

    [grypo] Kindle for PC works well. Kindle also offers apps for most smartphone OS (iOS, Android, etc)
  37. Lessons from Past Climate Predictions: IPCC AR4 (update)
    Just one follow up: Here are the tends 1990-now (°C/decade) ecmwf 0.151 giss 0.182 hadcrut 0.149 ncdc 0.153 GISTEMP runs a bit high, the other three appear to be in complete agreement. There are legitimate issues with how GISTEMP computes the upper arctic, this seems to call that method further into question. For an independent test of GISTEMP, I need mean temperatures averaged over 80°-90° to do a direct comparison with DMI (which is based on instrument measurements), but my suspicion is you'll find it runs hot compared to more physics-based models (both ECMWF and NCDC are heavily physics based, Hadcrut and GISTEMP are basically tonka toys in comparison, IMO). ClearClimateCode provides the gridded data I would need to make a direct comparison with DMI, but they are in a binary format I haven't gotten around to decoding. If anybody here is a data sleuth here is a link to a rasterized version of DMI, updated daily. If anybody here has a clue on how to decode the CCC grid files, I'd appreciate a bone thrown my way on that.
    Response:

    [DB] Please note WRT DMI:

    "DMI averages the data based on a regular 0.5 degree grid. That means it weights the region from 88.5N to 90N the same as the region from 80N to 80.5N despite the fact that there's a 40-fold difference in area.

    Ergo, the DMI value is very strongly weighted to the area immediately around the Pole and neglects the warming areas around the periphery."

    Essentially, the DMI "runs cold".

    H/T to Peter Ellis at Neven's.

  38. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    34, Norman,
    I just wish on these threads that more mechanisms would be developed to demonstrate how global warming will create more severe weather.
    Did you consider buying and reading the book that is the subject of this post? If not, why not?
  39. Lessons from Past Climate Predictions: IPCC AR4 (update)
    I wanted to post a clarification to some comments made about by Tom Curtis, who makes the following claim:
    2) In fact there is good reason to believe that two of the indices understate trends in GMST, in that they do not include data from a region known to be warming faster than the mean for the rest of the globe. In contrast, while there are unresolved issues relating to Gistemp, it is not clear that those issues have resulted in any significant inaccuracy. Indeed, comparison of Gistemp north of 80 degrees North with the DMI reanalysis over the same region shows Gistemp is more likely to have understated than overstated the trend in that region:
    I apologize for missing it earlier and any response that may have set him right, but I am busy getting ready for a trip and only had a chance to skim the comments, but this comment is in error. Actually of the three regularly updated series, NCDC probably has the best approach among them, and were I to pick one to put my money on, it would be this one. Unlike Tom's claims, NCDC does in fact interpolate, it uses something called "optimal interpolation' combined with empirical orthogonal functions to reconstruct the global mean temperature. Here's a standard reference on it (To quote from my comment on Lucia's blog): NCDC is the only method that incorporates fluid mechanics into their reconstruction. That is, they use pressure, temperature, and wind speed to reconstruct the various fields in a self-consistent fashion, and they use an empirical orthogonal function approach to do so. (he person who is the closest to this, as I understand it, is Nick’s code. Mosh can update me on that. Nick Stoke's Moyhu index uses an OLS based approach that also (in some sense) produces an "optimal interpolation". I also like NCDC's approach because they can estimate the uncertainties in the measurement. Those of us in physics would crucify any of you guys trying to stand up and present graphs that don't have uncertainty bounds on them (unless the uncertainty bounds are comparable or smaller than the thickness of the plot line). Secondly, simply making a correct, without being able to set bound on it, doesn't guarantee that the "change for change's sake" is an improvement over the simpler technique. With GISTEMP, the evidence is that it runs "hot" over the last decade compared to HadCRUT, NCDC and ECMWF. ECMWF is a meteorological based tool. An ascii version isn't currently available (to my knowledge), I'm trying to see if I can get that changed. In the mean time here's a rasterized version in case anybody wants to play with it I also think a lot has been made about GISTEMP being better. This smells purely of confirmation bias. I think people are picking GISTEMP because it runs hot (they like the answer) not because they understand in any profound way how it works. Truthfully, if you compare the series: You really have to squint to tell them apart. My personal predelection is to use all of the data series together, it's more consistent if your goal is to compare against a mean of models, than say cherry picking one data series, especially when your defense of it is utterly flawed and only demonstrates the depths of your own ignorance on this topic: (-Snip-). (What is magical about smoothing over a 1200-km radius. Why do you need two radiuses to compare? Do you realize how ad hoc using two different radiuses basically drawn from a hat and just visually comparing the products truly is???) (-Snip-). There would have been no serious criticism to using GISTEMP, if Dana hadn't mistakenly started with a year that was an outlier in estimating his trend. (This is another thing you get crucified for in physics presentations.) The better thing to do is shift the period to 2001, move away from the outlier when comparing trend. The best is to regress your data with MEI as Tamino does and remove this natural fluctuation that is not been captured by the GCM models before attempting a linear regression. Then you are free to pick any start and end point you please. But otherwise, issues with OLS sensitivity to outliers near the boundaries should trump other considerations. Science starts by considering the merits of a technique, and not its outcome, in determining which technique to use. ECMWF and NCDC are heads above the other two methods. (-Snip-) (-Snip-). I also find it interesting that he thinks mistakes that would get him reamed at a science conference (and I'm being *really nice* compared to how some of us behave there) constitute nitpicking. If you're going to blog in this area, you need to start with the assumptions 1) you're not smarter than everybody else, 2) other people have valid contributions and viewpoints to make that should influence your future blog postings, and 3) if you are going to disregard criticism of your post, why bother posting? It just ends up discrediting you and the viewpoint you are advocating in favor of.
    Response:

    [DB] Multiple inflammatory statements snipped.  Please rein in the inflammatory tone and rhetoric; confining your postings to the science with less inflammatory commentary is highly recommended.

    "you need to start with the assumptions 1) you're not smarter than everybody else"

    You would do well to remember this yourself.

  40. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Eric (skeptic) @ 32, Thanks for the link, I have already been there and posted on this thread and it does not explain much. A warmer atmosphere can hold more water vapor, yes. Does that mean it will increase rain? Might but it would not have to. It can hold more water vapor does not mean more rain will fall. "Atmospheric blocking leads to a stagnation of weather patterns. As you are well aware, atmospheric patterns tend to repeat themselves. In the case of blocking, the same pattern repeats for several days to even weeks. This can lead to flooding, drought, above normal temperatures, below normal temperatures and other weather extremes. It is important to recognize a blocking pattern in its initial development. With this awareness, you will be able to forecast out to several days in advance with a high degree of accuracy." Source of above quote. Droughts, floods and heat waves are not a random fluctuation anywhere on the earth. They are created by known weather patterns. A blocking system is responsible for many of the extreme long-term weather disasters. In order to link Global Warming to these extremes, it would be necessary to create a physical mechanism where global warming will increase the number and intensity of these blocking systems. It there is no mechanism found then stating extreme weather events are like loaded dice is an incorrect view because there is nothing random about them. I am still looking for such a link but have not yet found one.
  41. Lessons from Past Climate Predictions: IPCC AR4 (update)
    As Tom identifies @92, there's always a challenge in keeping wording of a post both correct and accessible to the general public. For example, Phil Jones' BBC interview. What he said was scientifically and statistically accurate, and what most of the public got from it was "no warming since 1995" - not at all what he actually said. This post is intended for a broad audience. The language could have been more precise from a statistical standpoint, but the more technical you get, the more of the general audience you lose. My suggestion for those who are nitpicking the language is to go do the analysis for yourself on your own blog. Then you can use whatever language you think is appropriate.
  42. Lessons from Past Climate Predictions: IPCC AR4 (update)
    Chris @90:
    "So first the accuracy of the projections is "difficult to evaluate", but then we find it's "reasonably accurate", and then it's sufficiently accurate that one can have some confidence that it will eventually add to the evidence that climate sensitivity is around 3 oC. Aren't those interpretations somewhat incompatible?"
    No! Think of yourself as trying to predict the match between the AR4 A2 20 year trend in 2020, and the trend of observed GMST between 2000 and 2020. Well, based on eleven years data, that 'accuracy' is difficult to evaluate, ie, to predict. It is difficult to evaluate because an 11 year trend is a very short trend in climate terms with a high noise to signal ratio. Changing the start or end point of the trend by just one year can make a significant difference to the trend. Hence, "it's difficult to evaluate the accuracy of its projections at this point". However, though difficult to evaluate, we are not completely without information regarding the accuracy of the projection. The information we do have suggests that it is more probable than not that the GMST trend will lie within error of the AR4 A2 multi-model projection. In this it contrasts with a host of other possible projections, including some actually made by AGW 'skeptics'. For those other projections, and based on evidence to date, it is more likely than not that the GMST trend will not lie within error of those projections (where within error is based on model mean variance). So, unlike those other possible projections, the AR4 A2 projections are "reasonably accurate" and give some (but not a great deal) confidence that the actual climate sensitivity is close to that of the models. We could be precise about this. But doing so would defeat the purpose of keeping the article accessible to the general reader. What I have been convinced of by the traction the argument of inconsistency has received is, not that it is correct, for it is not, but that as stated the conclusion can foster confusion.
  43. Lessons from Past Climate Predictions: IPCC AR4 (update)
    NewYorkJ Yes, taking a look under the bonnet of the ensemble cast makes it clear that attempting to determine climate sensitivity (essentially what everyone is talking about) from such a short period won't work. Here's a rundown of the models, their equilibrium and transient sensitivities* and their 2000-2010 trends: BCCR-BCM2.0    n.a.    n.a.        -0.03K/Decade CGCM3.1(T63)    3.4    n.a.         0.29K/Decade CNRM-CM3    n.a.    1.6               0.09K/Decade CSIRO-MK3.0    3.1    1.4            0.42K/Decade GFDL-CM2.0    2.9    1.6              0.08K/Decade GFDL-CM2.1    3.4    1.5              0.09K/Decade GISS-ER    2.7    1.5                    0.16K/Decade INM-CM3.0    2.1    1.6                0.34K/Decade IPSL-CM4    4.4    2.1                  0.28K/Decade MIROC3.2(med)    4.0    2.1         0.13K/Decade ECHO-G    3.2    1.7                     0.15K/Decade ECHAM5/MPI-OM    3.4    2.2       0.28K/Decade MRI-CGCM2.3.2    3.2    2.2         0.08K/Decade CCSM3    2.7    1.5                       0.29K/Decade PCM    2.1    1.3                           0.13K/Decade UKMO-HadCM3    3.3    2.0           0.13K/Decade UKMO-HadGEM1    4.4    1.9         0.11K/Decade There really isn't a discernible pattern at this stage linking sensitivity to temperature trend in the model outputs. I actually think the ensemble mean probably is too "warm", in the short term anyway, mainly because a few of the model cast do not include indirect aerosol effects. If you've ever seen a chart showing recent radiative forcing factors, such as this one in AR4 SPM, you'll know why this is a major omission. I've so far identified two models - INMCM3 and CCSM3.0 - which don't include indirect aerosol effects and it's no surprise they both exhibit two of the largest trends over 2000-2010. If just those two are removed from the cast the ensemble mean drops from 0.18K/Dec to 0.16K/Dec. Over the longer term it becomes less important: there is no difference in the 2000-2099 trend between the original 17-member cast and my cut-down 15-member version. Another interesting finding along this train of thought is that the median average is only 0.13K/Dec and 11 of the 17 members feature a lower trend than the ensemble mean. * http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch8s8-6-2-3.html
  44. Galactic cosmic rays: Backing the wrong horse
    tblakeslee#16: "CERN experiment was much more abstract" Your first link is to the familiar Laken 2010, discussed here. This 'real world experiment' compared cloud fractions computed via general circulation models. And no, CERN is not duplicating/confirming Svensmark.
  45. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    muoncounter Here is an article that figures out how much of the Texas drought of 2011 was a result of global warming. "I think we’re pretty close now. This record-setting summer was 5.4 F above average. The lack of precipitation accounts for 4.0 F, greenhouse gases global warming [edited 9/11/11] accounts for another 0.9 F, and the AMO accounts for another 0.3 F. Note that there’s uncertainty with all those numbers, and I have only made the crudest attempts at quantifying the uncertainty. But this will do until something better comes along. (Also note that the AMO index is not, strictly speaking, independent of the global mean temperature, but the AMO trend since 1900 is weak so any double-counting here is very small. [edits 9/11/11]) Link to article of the above quote.
  46. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    #30, Norman: there are threads about extreme event causation from time to time: e.g. /extreme-weather-global-warming.htm Some other promising threads devolved into debates about insurance company record keeping.
  47. Galactic cosmic rays: Backing the wrong horse
    15, Paul D, I did not read it as you did, but I can see that it could cause confusion. Perhaps: "Despite an excellent rebuttal here on SkS, supported by Jasper Kirkby's own words, the popular press is still pushing the preliminary CERN CLOUD results..."
    Moderator Response: [muoncounter] Fixed opening paragraph, thanks to Paul D and Sph.
  48. Lessons from Past Climate Predictions: IPCC AR4 (update)
    Tom, I find it interesting that Jonathan and I seem to be the only two people that consider that the last section of the top article is problematic. Incidentally, I think all the other stuff flying around about this analysis is unproductive nit-picking. I agree that the term "accuracy" can have gradations of meaning. The problem with the use of "accuracy" in the last section of the top article is that its use in describing the AR4 projections changes throughout the section. So first the accuracy of the projections is "difficult to evaluate", but then we find it's "reasonably accurate", and then it's sufficiently accurate that one can have some confidence that it will eventually add to the evidence that climate sensitivity is around 3 oC. Aren't those interpretations somewhat incompatible? On their own the AR4 projections have little to say about climate sensitivity and I don't think we can presuppose that they will eventually support a climate sensitivity near 3 oC. On the other hand comparison of empirical surface temperature progression with simulations from the late 1980's does support our confidence arising from a wealth of other data, that the likely value of the climate sensitivity is near 3 oC. I don't think this is "creative misunderstanding". It's simply how my mind interprets the text! I have quite a lot of confidence that the best value for the climate sensitivity is around 3 oC, but I don't think the AR4 projections (and their comparisons with surface temperature progression), gives us much insight into climate sensitivity, nor that we can presuppose that they will in the future support a value near 3 oC.
  49. Pielke Sr. Agrees with SkS on Reducing Carbon Emissions
    No, we didn't comment on the specific plan because I don't think anyone at SkS has read it, Eric. We'd be interested in hearing your comments one you have a look.
  50. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    #29, Norman. Think of it as a notional graph- a graph of temperature "events" in multiple locations compared to the baseline for those locations. The daily average, low and high could all be considered events. The PDF of events would be normally distributed as shown given a sufficient number of locations. With "climate change" the PDF would probably shift right and flatten out as depicted by muoncounter above (note that the PDF is still in comparison to the pre-CC baseline). I disagree a bit though, I think the right tail will be truncated somewhat by physical limits imposed by the initiation of convection.

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