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Sunday, May 29, 2016

Uncertainty in CO2's Raditive Forcing < 1%

From a new article in Geophysical Research Letters:


The uncertainties in climate change lie in (1) clouds, and (2) the carbon cycle, not in CO2 or how greenhouse gases interact with infrared radiation emitted by the Earth and its atmosphere. Because the latter are very amenable to fundamental physics, the kind of stuff physicists have spent 300 years getting good at -- read Chapters 2-4 in Pierrehumbert's textbook -- the Planck Law, energy conservation via the two-stream equations, and numerical solutions to the  underlying PDEs using the HITRAN spectroscopic database.

Climate contrarians (quote-unquote) never get this. They want only to argue about CO2.

81 comments:

  1. No, contrarians / sceptics don't 'only want to argue about CO2' - they want to talk about solar radiation and ocean cycles, which the IPCC doesn't (much)

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  2. Is it possible to convert the radiative forcing in the article into degrees of climate sensitivity? I have read elsewhere that the number is between 1 and 1.5 degrees C. Do you know if that's correct?

    Cheers

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  3. Contrarians love to talk about solar cycles but would rather ignore the reality. Forcing from solar variability since 1750: +0.05 Wm^-2 (0.0 to +0.10). Forcing from Co2: 2.83 Wm^-2 (2.54 to 3.12) - http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter08_FINAL.pdf

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  4. So you would prefer it if contrarians / sceptics only talked about CO2, which is the very thing that David Appell is criticising them for ?

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  5. No. Just wish they would stick to the science.

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  6. Then do you accept that the 133 sceptic papers published in the first three months of 2016 and listed at http://notrickszone.com/skeptic-papers-2016/#sthash.BMXWtI2v.ErYkXMI5.dpbs are 'stick[ing] to the science' ?

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  7. You want me to evaluate 133 papers for you? No thanks. If you have specific questions please feel free to ask.

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  8. Although if you look at the very first paper you'll see that it was published by OMICS Publishing Group. It think it's fair to say that it is probably not worth reading if you can't get it published in a real journal.

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  9. Maybe consider going to peer reviewed science rather than predatory journals if you want a clearer understanding of climate change. I would recommend the IPCC

    Although if you're ever interested in publishing nonsense, OMICS would be happy to do so for $2700. No pesky peer review to get between you and a pubished paper! The only catch is that they charge you another $800 to get your paper withdrawn if you ever need to cleanse your reputation.

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  10. Out of curiosity Richard, did you read that first paper and think "Yes, this is good science!" Was there no skepticism whatsoever? No little glimmer of doubt?

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  11. My specific question is how can you claim that the sceptics are not 'stick[ing] to the science' when 133 scientific papers have been published in a variety of journals in the first three months of this year ?

    Regarding the first paper by Kelly, it deals mainly with USA data, which the alarmists would reject because it's not global data (which AFAIK is not available for precipitation / hurricanes / flooding over long time scales) - however, he does also look at data from some other parts of the world.

    Perhaps you don't like it because it references blogs and newspapers ?

    What specifically in the data and / or the interpretation of the data do you regard as not 'good science' ?

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  12. Richard says "My specific question is how can you claim that the sceptics are not 'stick[ing] to the science' when 133 scientific papers have been published in a variety of journals in the first three months of this year ?"

    And references OMICS publishing - neatly illustrating my point.

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  13. But by all means, let's look deeper at this paper that you've held up as a shining example of skeptical science. After all, it would have to be pretty bad for some bloke like me on the internet to find any faults. A real turd. I'm happy to take a closer look if you like.

    Just to be clear, do you actually think the paper in question is good?

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  14. You say that the first paper by Kelly illustrates your point because of where it has been published, but that is only one out of 133 papers. You can easily find papers in that list that are published in the journals that you approve of.

    As with all papers, it has limitations. Please point out what you consider to be not 'good science' as I asked you at 8:58 am.

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  15. I suggested that you should stick to the science. In response you provided a list of papers. Presumably you endorse this list, but you are being a bit dodgy about that.

    Let's be clear before I waste any time. Do you actually think that the paper in question is good?

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  16. As I said, it has limitations, because most of it is focussed on American data; but it does include some information from non-American locations as well.

    The graphs are very small, so it's difficult for me to draw conclusions from them.

    Regarding temperature adjustments, they may have been made for good reasons; but I am reluctant to use the data from NASA GISS and NOAA NCEI, because the historical data seems to change every month.

    For me, there are no 'good' or 'bad' papers, unless they contain obvious flaws, and I haven't been able to identify any obvious flaws in the paper by Kelly. If you have found obvious flaws, please point them out to me,thank you.

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  17. "...I am reluctant to use the data from NASA GISS and NOAA NCEI, because the historical data seems to change every month."

    That's because of adjustments.

    This article explains it very well:

    "Thorough, not thoroughly fabricated: The truth about global temperature data: How thermometer and satellite data is adjusted and why it must be done," Scott K. Johnson, Ars Technica 1/21/16
    http://arstechnica.com/science/2016/01/thorough-not-thoroughly-fabricated-the-truth-about-global-temperature-data/

    especially the time-of-observation bias:

    https://judithcurry.com/2015/02/22/understanding-time-of-observation-bias/

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  18. I am not disputing that adjustment must be done. I only said that I'm reluctant to use NASA GISS and NOAA NCDC data, because that means that (say) May's data isn't only April's data plus the temperature for May; but I have to download the whole series because some historical data may have changed, and recreate the graph(s). With HadCRUT4 I don't have this problem. I can just add one temperature datum for May.

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  19. "...but I am reluctant to use the data from NASA GISS and NOAA NCEI, because the historical data seems to change every month."

    These monthly changes happen for EVERY temperature record I know of -- NOAA, GISS, Hadley, BEST, JMO, RSS and UAH.

    For example, the UAH LT global anomaly for 12/1982 was, in January of this year, -0.17 C. In April it was -0.16 C.

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  20. HadCRUT4 also makes changes to the "historical" data.

    In July 2014, the anomaly for Jan 1850 was -0.690 C.

    The most recent value is -0.702 C.

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  21. There are reasons that this paper was not published in an academic journal. The fact that it was not should be your first red flag. You asked whether I didn't like it because it referenced blogs, but this paper is published on a blog. It is not listed in the web of science. It is not archived at your local university. It has not been peer reviewed. Anyone with $2700 can post at OMICS and have the veneer of academia.

    Richard - you could publish your thoughts on correlation coefficients here if you liked and tell all your friends you're an academic.

    The fact that you chose this as an example of skeptics sticking to the science is both ironic and telling.

    But let's look at the paper. Would you agree that an academic paper shouldn't include any unsubstantiated claims - especially if those claims are easily shown to be false?

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  22. Here's one for you.

    In July 2014, HadCRUT4's anomaly for March 1875 was -0.63 C.

    For Apri 2016 it's -0.598 C.

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  23. Reply to David Appell :-

    Thank you for those examples. How did you find them ?

    Reply to Layzej :-

    Yes, please show me the unsubstantiated claims by Kelly that you believe are easily shown to be false, and I will evaluate them.

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  24. Richard,

    I download all the data every month and keep track of each month's numbers in a separate column on my spreadsheet. For HadCRUT4 I started doing this in July 2014. But not until this January for UAH.

    But I have discussed UAH's huge -- I mean huge -- adjustments in new versions:

    http://davidappell.blogspot.com/2015/04/some-big-adjustments-to-uahs-dataset.html
    http://davidappell.blogspot.com/2015/04/remarkable-changes-to-uah-data.html

    David

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  25. UAH (which I don't use because it's too short) would claim that they are continually improving their measuring / processing methods to remove errors.

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  26. Of course, Richard, everyone claims that about new versions.

    There are good reasons for new versions. But UAH's were so big -- about 3 times larger than the Karl et al changes that deniers are still whining about -- that they show important factors were being overlooked.

    UAH has a bad history of doing this, back to the mid-90s. It took years for them to correct a sign error, despite others (led by Ben Santer) pointing out their error for a long time.

    Spencer especially is hugely biased. I don't trust UAH at all.

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  27. Richard,

    Just in the summary you provided we find the unsubstantiated claims

    1) The compilation of temperature records are a source of problematic methodology of a kind not seen elsewhere in science.

    That's bold. No other science compiles observational data? Really?

    2) Under the umbrella term of “homogenisation”, there now seem to be a growing myriad of post-hoc adjustments to the original raw data that all seem to go in one direction, namely to increase the overall rate of global warming.

    Why is homogenisation in scare quotes? Do adjustments all go in one direction?

    Of course not. As our host showed a few weeks back that the NOAA adjustments lower the long-term trend.

    Claim 1 and 2 are completely unsupported in the paper. The author states that in a 1980 paper Hansen "showed 1980 temperatures were about 0.15ºC cooler than 1940. Now, NASA shows 1980 temperatures about 0.2ºC warmer than 1940."

    First, that's not true, but even if it where, it doesn't show that the difference is due to adjustments in the raw data. Possibly in 1980 Hansen only had access records from a handful of stations. Any difference may be the result of a larger data set.

    The author has not looked at a single adjustment let alone show that all seem to increase the overall rate of global warming.

    Of course he couldn't have since the claim is clearly false.

    This is the kind of work I'd expect on a blog by Steve Goddard. There is no way it would have passed peer review in an academic journal. I'm shocked that this even passed your sniff test.

    I'm more shocked that you would hold this up as an example of contrarians sticking to the science.

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  28. I did not hold up this Kelly paper specifically as an exmple of 'stick[ing] to the science' - I merely gave you a link to a list of 133 scientific papers published in the first 3 months of this year.

    Kelly did not say that no other science compiles observational data. He said that "The compilation of temperature records are a source of problematic methodology of a kind not seen elsewhere in science."

    I have no idea whether or not 'in 1980 Hansen only had access [to] records from a handful of stations' - that is pure conjecture.

    As I have said before, I'm not interested in the adjustments, because they have very little effect on the overall trends, or the trends for any specific period. (I often get flak from the sceptics for saying that)

    Looking at the NASA GISS data shows an annual anomaly (Jan-Dec) of +0.08°C in 1940 and +0.27°C in 1980 which is a difference of +0.19°C, so Kelly's figure of about 0.2°C is correct.

    The paper is entitled 'Trends in extreme events since 1900' so that's what I was concentrating on, rather than adjustments to the temperature record. Is there anything in the paper relating to extreme events that does not 'stick to the science' ?

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  29. Richard says: "Kelly did not say that no other science compiles observational data. He said that "The compilation of temperature records are a source of problematic methodology of a kind not seen elsewhere in science.""

    And it is a completely unsubstantiated claim. We both agree that no academic paper would include such rubbish.

    Richard says "I have no idea whether or not 'in 1980 Hansen only had access [to] records from a handful of stations' - that is pure conjecture."

    Yes. The paper provides nothing to substantiate their remarkable claims whatsoever. We are left guessing. But it is completely beside the point since the temps in 1980 still show well below 1940: http://woodfortrees.org/plot/gistemp/to:1980/mean:60

    Hanson's analysis ended in 1980 so whatever happened after that was obviously not included. In 1980 it wasn't so easy as logging on to the NOAA web site and downloading last months temp records. Remarkably, even though temps had fallen since 1940, Hansen was predicting this: http://woodfortrees.org/plot/gistemp/mean:60/from:1977/plot/gistemp/to:1980/mean:60

    I just want to confirm before we continue. Do you still believe that this is a good example of skeptical science? Even though this paper is not published in an academic journal? Even though it has not passed peer reivew? Even though the paper contains unsubstantiated and false claims?

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  30. As I said before :-

    The paper is entitled 'Trends in extreme events since 1900' so that's what I was concentrating on, rather than adjustments to the temperature record. Is there anything in the paper relating to extreme events that does not 'stick to the science' ?

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  31. Richard says: "Kelly did not say that no other science compiles observational data. He said that "The compilation of temperature records are a source of problematic methodology of a kind not seen elsewhere in science.""

    Astronomy must often correct data for optical aberrations. Economics corrects nearly all raw data for inflation, currency conversions, population, etc. Census counts themselves are corrected for missed subsets of people (such as the homeless). Raw polling data is often corrected in an attempt to more representative.

    Anyway, so what? Measuring long-term temperature changes is very important. Since you can't get the data you want, you have to do the best with the data you have. Scientists have been working for decades now on how best to do that.

    It was telling when Richard Muller complained about the temperature results. Deniers loved him then. To Muller's great credit he went out, got funding, built a team and did his own analysis. BEST found the same results as everyone else.

    Of course, after that deniers had to deny him too. It's not the data they're unhappy with, it's the results.

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  32. Of course I agree with that. BEST has the longest records and the most stations. That's why I used HadCRUT4 and / or BEST in many of my posts here. The only problem with BEST is that it is updated (as I understand it) omly once per year.

    My question would be, if we don't use the whole of a long term record (because it includes too much natural variability, if I understand you correctly) how do we break it up into smaller chunks (since you don't seem to like my method of doing so) ?

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  33. Richard wrote:
    "BEST has the longest records and the most stations. That's why I used HadCRUT4 and / or BEST in many of my posts here."

    That doesn't necessarily make them superior. (I've heard it's possible to construct a good dateaset using only 50-100 stations around the world.) There are other, more important considerations, especially how they handle regions that have no stations. Most of the groups do this in their own way -- one interpolates, on averages, one kriges, and none is a priori best as far as I can see. (Well, maybe Cowtan & Way is a little superior.)

    "My question would be, if we don't use the whole of a long term record (because it includes too much natural variability, if I understand you correctly) how do we break it up into smaller chunks (since you don't seem to like my method of doing so) ?"

    First answer why you want to to break it up in to smaller chunks. What are you trying to calculate? The effect of an ENSO? A volcano? Solar changes? CO2? Each could require a different time interval.

    If you're trying to calculate climate change, you have to decide what you mean by climate. Climate chantge is the long-term change over a period where natural variation average to zero or close to it. In that case, a decade or 15 years is usually too short, since a string of ENSOs can pull temperatures lower than the climatic average. That happened in the first decade of 2000s, when La Nina conditions began to predominate until today's EL Nino. From about 1985-2000, El Nino conditions predominated and added to global warming, pushing rates up past the rate of change of the underlying climate, which some misinterpreted as strong climate warming.

    Since the AMO and PDO can have an effect on temperatures (and hurricanes, for the AMO), and they can take up to 60 years or so to complete a full cycle, you could argue that you need that long of a time interval to draw conclusions about climate change. But then you have a preponderance of aerosols (air pollution) from about WW2 to the implementation of clean air acts in the US and Europe, and that pollution held temperatures down, and that wasn't part of "climate" change either.

    In short, there's no easy answer, and giving a number without these kind of caveats doesn't help. The WMO recommends a period of at least 30 years for conclusions about climate. If I use a period less than 30 years I try to remember to label my post with my "Numerology" figure, but that's all it is -- numbers that may (or may not) be interesting, but which aren't about climate change.

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  34. Thank you David, I agree with all of that. I have seen graphs that purport to indicate that each decade was warmer than the last; but as you say, without caveats that is pretty meaningless, qauite apart from the fact that the start and end dates are purely arbitrary, and will not coincide with anything meaningful for ENSO, AMO or PDO.

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  35. Richard says: Is there anything in the paper relating to extreme events that does not 'stick to the science'?

    Richard - The examples I gave were from the summary you provided. Does it not faze you that false statements could be found after such a superficial review?

    Digging deeper has not yielded anything more than the rhetoric and BS described previously. The falsehoods are so numerous that I suspect we could be at this for weeks if you are willing to shrug each away.

    If you still think that this paper is worth discussing then maybe you could identify a single point in the paper that is true, substantiated, and in some way contradicts the consensus?

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  36. Everything in the Kelly paper (which is also at http://www.omicsgroup.org/journals/trends-in-extreme-weather-events-since-1900--an-enduring-conundrum-for-wise-policy-advice-2167-0587-1000155.php?aid=69558 ) is substantiated because he gives references for each one, so that is not a problem. Truth of course is subjective, so we could indeed be here for weeks if we argue about what is true.

    I don't know what 'the consensus' says about extreme events, so again we could be arguing for weeks about that.

    However, we can look at what the paper says about extreme events.

    1. Kelly's first chart 'shows that the periods of maximum warming or cooling rates are all in the 19th century or at the start of the 20th century.'

    Do you dispute that the chart shows that ?

    2. Kelly's point (i) says 'All the huge extreme changes took place over 40 years ago, with the great majority occurring prior to 1950.'

    Do you dispute that the chart shows that ?

    3. Kelly's point (ii) says 'The huge CO2 emissions have not been associated with a single global warming acceleration extreme since 1951, over 60 years ago.'

    Do you dispute that the chart shows that ?

    4. Kelly's point (iii) says 'Since the 1970's, the climate extremes' range appears to be narrowing, with each accelerated warming and cooling trend rate getting smaller.'

    Do you dispute that the chart shows that ?

    5. Kelly's point (iv) says 'When major (minor too) extremes occur, the climate system does not hit a "tipping point" of positive feedbacks. Instead, the natural climate responds with negative feedbacks to bring the climate back to some
    level of short-term equilibrium.'

    Do you dispute that the chart shows that ?

    That will do for starters.

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  37. Richard says: "Truth of course is subjective, so we could indeed be here for weeks if we argue about what is true."

    I'd be happy if you could show that it was even supported by evidence.

    Richard says: "I don't know what 'the consensus' says about extreme events, so again we could be arguing for weeks about that."

    Just cite the IPCC and show how it is somehow contradicted by anything that Kelly writes.

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  38. Richard, re: extreme weather

    http://www.yaleclimateconnections.org/2016/05/climate-change-and-extreme-weather/

    http://www.nap.edu/catalog/21852/attribution-of-extreme-weather-events-in-the-context-of-climate-change

    I looked at the Kelly paper. It is not impressive. Frankly I couldn't even read the axes on the figure, no matter how much I magnified them.

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  39. Reply to Layzej :-

    As usual, you haven't answered my questions.
    As usual, you expect me to read everything that the IPCC has written.

    Reply to David Appell :-

    The Yale link is too brief to be informative, let alone convincing.

    The National Academies Press link is to a book costing $88 ($59 paperback) so that will not be on my 'to be read' list any time soon.

    The y-axis is HC4 per century trends (°C) from -80 to +80
    The x-axis is months / years from Jan. 1850 to Oct. 2014

    Once again, I am not upholding the Kelly paper as a shining example. I'm sure that you can find much better examples from more prestigious journals in the list of 133 sceptic papers published in the first three months of this year.

    http://notrickszone.com/skeptic-papers-2016/#sthash.BMXWtI2v.ErYkXMI5.dpbs even summarises them for you.

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  40. The NAS offers a free PDF download.

    Or you can remain ignorant, which you seem to get some delight from.

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  41. Many thanks for that David. It will take me a while to read it of course. Meanwhile http://www.heritage.org/research/reports/2016/04/the-state-of-climate-science-no-justification-for-extreme-policies presents an alternative view.

    At http://www.climatechange2013.org/images/report/WG1AR5_Chapter02_FINAL.pdf the IPCC says :-

    “the compelling arguments both for and against a significant increase in the land area experiencing drought has hampered global assessment.”

    The IPCC also found evidence for increases, decreases, and no trend at all in flood activity or severity. (same reference)

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  42. Richard says: "As usual, you haven't answered my questions."

    Richard, who cares if the time derivative of the monthly mean surface temperature "shows that the periods of maximum warming or cooling rates are all in the 19th century"

    Has he taken even a superficial look at why that may be? Does that in any way challenge the consensus?

    Richard says: "As usual, you expect me to read everything that the IPCC has written."

    Yes. That's kind of my point. How can you "stick to the science" if you don't have a passing familiarity with it? Without the basics, your bullshit filter is entirely broken. You are easily taken in by a paper with tons of graphs and rhetoric but that doesn't actually show anything interesting.

    You started by suggesting that contrarians "want to talk about solar radiation and ocean cycles, which the IPCC doesn't (much)"

    But in fact you have no idea what the IPCC says about forcing from solar variability. It turns out this is fairly well constrained and quite small compared to CO2.

    And you imagine the IPCC doesn't like to talk about ocean cycles but how could you know if you haven't even looked? There is an entire chapter devoted to this.

    Stick to the science. And yes, that means you have to have a passing familiarity with it.

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  43. Who cares if the meximum warming and cooling rates are all in the 19th. century ? You should, because you claimed data (from an unspecified source) from 1816 showing that the warming trend was accelerating.

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  44. The graph that you are referring to is simply garbage. If you have a warming trend with fluctuations and your goal is to eliminate that trend then one way to do that is to take the derivative. This is exactly what the C3 political site does, from which Kelly appropriated the graph. As most people already know, taking the derivative of a noisy signal multiplies the amplitude by the frequency so that the high frequency noise is accentuated and the low frequency long-term trend is eliminated.

    The graph is garbage for several reasons: 1) No one claims that it's the year-to-year variability that is the climate problem we face. Rather, the problem is that we have had a fairly stable climate in which civilization has flourished and now we are engaged in massive experiment in altering the atmospheric and ocean circulation, increasing the probability of extreme heat events and changing the hydrologic cycle. 2) Take a normal distribution in temperature and move the mean by 1 standard deviation. Now calculate the probability of extreme heat events out at 4-sigma from the mean (relevant to the original distribution). How much has the probability gone up? 2)Even if you wanted to calculate the year-to-year variability -- which you wouldn't --- the fact that the C3 site omitted the 2-sigma uncertainty in the yearly trend makes the graph itself meaningless. If you look at the HADCUT4 data with the 2-sigma uncertainty one can readily see that the uncertainty increased the further back in time one looks. When you take a 2 point derivative with such large uncertainty the uncertainty in the trend is massive. Kelly of course couldn't bother to do even a largely irrelevant calculation correctly because he was more interested in writing a piece of political science rather than actual science.

    And as for that quote that the Heritage Foundation mined from the IPCC report, a report you've admitted that you haven't read, that same report goes on to say:

    "Despite differences between the conclusions drawn by global studies, there are some areas in which they agree. Table 2.13 indicates that there is medium confidence of an increase in dryness or drought in East Asia with high confidence that this is the case in the Mediterranean and West Africa. There is also high confidence of decreases in dryness or drought in central North America and north-west Australia."

    This is consistent with the view of most climatologists that the hydrologic effect of a warming climate is, to put it simply, make the wet areas wetter and the dry area dryer. One paper that explored this phenomenon in the Mediterranean is that by Hoerling et al, "On the Increased Frequency of Mediterranean Drought"

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  45. Many thanks for the citation. Is there anything more recent than 2010 ? The one thing that I have noticed when visitng countries bordering the Mediterranean (Morocco, Tunisia, Egypt, Spain, Italy, Greece) has been the constant sight of sprinklers watering the crops. I guess that they get a lot of their water from mountain ice melting in the spring and summer.

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  46. Off the top of my head, there is of course the 2015 paper by Kelley et al on drought in the Fertile Crescent --- especially Syria -- which was wildly misinterpreted by many. There is also the paper by Coumou & Rahmstorff (2012) on climate extremes. A rather sobering look at the possibility of unprecedented drought in the American southwest and central plains is by Cook et al (2015) . One paper by Hansen et al (2012) on extreme anomalies in temperature due to changes in the mean temperatures is similar to what I wrote above.

    There are plenty more on the subject -- I'm sure you can find them.

    Do the calculation I suggested --- assuming a normal distribution in temperature, how much does the probability of a 3 or 4 sigma event increase when the mean temperature increases by 1 standard deviation? The answer may surprise you if you never thought about this before.

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  47. Thank you for the citations. Sorry I don't know enough statistics to do the calculation you suggested. For HadCRUT4 the mean is -0.105 °C and the standard deviation is 0.285 °C so increasing the mean by one standard deviation would make it +0.180 °C. I thought the probability of an n-sigma event was always the same for a normal distribution. Of course it would take a large change in future temperatures to increase the mean by 0.285 °C over the whole range since 1850.

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  48. Richard says: Who cares if the meximum warming and cooling rates are all in the 19th. century ? You should, because you claimed data (from an unspecified source) from 1816 showing that the warming trend was accelerating.

    Warming is accelerating. What has that to do with the graph of the derivatives? The derivative is the instantaneous rate of change. Not the trend. Likely this finding is the result of poor coverage further back in time. With perfect coverage we should expect the signal would be fairly monotonous.

    Can you see why this paper wasn't published in a real journal?

    My dad had a saying: "bullshit baffles brains." That seems to be the strategy of the contrarians. Show a number of complicated but meaningless graphs. Add rhetoric. Voila! Nothing that will impact the science but enough to nourish the doubt of those inclined towards doubt.

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  49. Is that your summary of all the 133 sceptical papers, even those that were published in journals that you approve of ? Science is often advanced by those who doubt.

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  50. Richard says: "Is that your summary of all the 133 sceptical papers"

    How many would I need to dig through before I found one that wasn't a big old turd? This was at the very top of the pile and one that you endorsed. Are there any worth reviewing? Are you even qualified to know?

    Richard says: "even those that were published in journals that you approve of ?"

    Are you suggesting that you approve of the OMICS Publishing Group? Seriously?

    Richard says: "Science is often advanced by those who doubt."

    Doubt is cheap. What we need is skepticism. This is what scientists bring to the table. You should start with the IPCC if you want a skeptical review of the science. Once you have the basics you may have some chance of evaluating these 133 papers.

    So to summarize, I wouldn't "prefer it if contrarians / sceptics only talked about CO2", I just wish they'd stick to the science.

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  51. You don't know if they stick to the science if you cannot be bothered to read their papers.

    I appreciate thst you are lacking in reading and comprehension skills, since I was asking you to look at the papers that are published in journals that you approve of. This is obviously not the same as saying that I approve of every (or any specific) journal in which the 133 papers are published.

    Also I repeatedly denied that I endorsed the Kelly paper, or any of the 133 papers which you haven't even bothered to read before dismissing them with a foul metaphor.

    You regard the IPCC as sceptical. You obviously have no idea that the IPCC was set up to produce reports that support the UNFCCC to "stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system" (quoting from the introduction to the convention) not to produce reports that are sceptical of that anthropogenic interference with the climate system.

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  52. Richard: I repeatedly denied that I endorsed the Kelly paper, or any of the 133 papers

    This is absurd. Why would you provide nonsense as an example of contrarian science? Why should I read papers that even you don't think are any good?

    The IPCC reports are just a summary of the science. You can use whatever fantasy you like to avoid the science. I wish you wouldn't.

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  53. Layzej wrote:
    "This is absurd. Why would you provide nonsense as an example of contrarian science? Why should I read papers that even you don't think are any good?"

    Totally agree with you. A few days ago, with his replies on David Archer's book and then the NAS report on extreme weather, I concluded Richard is not at all interested in debating the science, just being contrary for the sake of being contrary. This latest shows it again.

    I'm now filtering my email so all comments under his name go straight to Trash.

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  54. (Of course, I can understand how sometimes it's satisfying to hunt trolls and trap them in a corner, if for no other reason than to see how they manufacture a way out.)

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  55. Reply to Layzej :-

    I never said that I don't think the 133 sceptical papers are any good. Once again you fail to demonstrate basic reading and comprehension skills. As I said before, the IPCC reports are not (and were never intended to be) just a summary of the science. Read the introduction to the UNFCCC convention again. If you cannot understand that, you will never understand anything else.

    Reply to David Appell :-

    I said that it would take me time to read Archer's book and the papers on extreme weather (about which the IPCC lowered its certainty level, and about which we will need many more examples from all parts of the world)

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  56. JoeT says: "Do the calculation I suggested --- assuming a normal distribution in temperature, how much does the probability of a 3 or 4 sigma event increase when the mean temperature increases by 1 standard deviation? The answer may surprise you if you never thought about this before.

    This image may help illustrate: http://www.sixsigma-institute.org/sixsigma_images/six_sigma_normal_distribution_2.jpg

    If you move the mean one standard deviation to the right then a four sigma event now happens with the frequency of a three sigma event. It becomes (I think) about 43 times more likely.

    A three sigma event becomes about 17 times more likely.

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  57. JoeT says: "Do the calculation I suggested --- assuming a normal distribution in temperature, how much does the probability of a 3 or 4 sigma event increase when the mean temperature increases by 1 standard deviation? The answer may surprise you if you never thought about this before."

    I did a very similar calculation here:

    http://davidappell.blogspot.com/2015/07/why-very-warm-events-are-much-more.html

    What I found is that if the background temperature changes by some amount (what I called T2-T1 in that post), the probability of a fluctuation to some temperature increased exponentially with T2-T1.

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  58. And (as I also said before) to increase the mean by one standard deviation would require increasing the mean temperature since 1850 (not the present temperature) of -0.105 °C by one standard deviation (+0.285 °C) to a value of +0.18 °C which would take a very long time.

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  59. I was hoping that I was wrong, but unfortunately I just checked to see what Richard did. He took the mean and standard deviation of the Hadcrut4 global yearly temperature data from 1850 to 2015.

    Oy.

    If you really don't understand Richard what we're talking about, it's always best to ask. Why in the world would one even imagine that the Hadcrut4 global yearly temperature data would form a normal distribution?

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  60. That was what I was thinking. If it is not a normal distribution, then Layzej's link is totally irrelevant. Why did you ask me to assume it was a normal distribution if you knew that it was not a normal distribution ? How does that help dialogue ?

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  61. I was trying to help you understand why the probability of temperature extremes increases dramatically with an increase in the mean temperature. I said nothing about assuming the Hadcrut4 global yearly temperature data is a normal distribution. Layzej's link of course is exactly relevant.

    I see you're confused; go read David's link.

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  62. By the way, Layzej your answer is correct if you phrase the question as: How does the probability increase if the temperature is 4 sigma from the mean AND HIGHER and the mean temperature increases by 1 sigma. That's definitely a legitimate way to phrase it.

    I was trying to make the problem as simple as possible by looking at the probability at 4 sigma (not -- and higher). In that case the probability increase is a factor of 33 (actually exp(7/2)) for 4 sigma and 12 (exp(5/2) for 3 sigma.

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  63. Reply to JoeT :-

    Both David Appell and Layzej assume a normal distribution.

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  64. That's correct, they do. Your point?

    It's clear you don't have any idea when it might be appropriate to assume a normal distribution. Think about the mean temperature for each day in your city over the course of a year. You'll have a few very cold days and a few very hot days. However, a huge fraction of those days will have a temperature close to the mean. Now maybe one year isn't representative of the climate in your area. Let's average the mean temperature for each day over 20 years. Now divide up your graph into intervals from coldest to hottest temperature and plot how many days were in each interval. Chances are that it would look very much like the graphs in David's link. That's pretty close to a normal distribution.

    Now let's choose a 20 year interval say from 1956 to 1975. And we'll choose another 20 year period from 1996 to 2015. Plot the curves on top of each other. Did the mean shift? What about the standard deviation? It's possible even the sd changed, but to make the illustrative problem simpler I asked you to assume it doesn't change. But if it does change we can calculate the ratio of the probabilities for a 3 or 4 sigma event anyway.

    Now, instead of plotting a graph for your home town, how about we consider a region in the Arctic -- say Barrow, Alaska ---- where the mean temperature is increasing faster than the rest of the world. How has the probability of an extreme heat event changed now? (The question is rhetorical.)

    Or let's choose a place like Titlagarh, India that had near fatal wet bulb temperatures (David wrote about this recently). I can’t say off the top of my head if the wet bulb temperatures form a normal distribution, but chances are that it’s close. Even if it’s not – if we can figure out the pdf – we can then estimate how much the mean temperature has to increase so that there is a finite probability say of having a few fatal wet bulb temperature days each year.

    Is that clearer now?

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  65. the point is that you said :-

    Why in the world would one even imagine that the Hadcrut4 global yearly temperature data would form a normal distribution?

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  66. When you have a temperature series that cools and warms, cools and warms, cools and warms, all varying about a slow warming trend 0f +0.49 °C per century, why would you assume a normal distribution ?

    And, if the mean is -0.105 °C and the standard deviation is 0.285 °C how many years would it take for the mean since 1850 to increase by 1, 2, 3 or 4 standard deviations ?

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  67. Richard Mallett.

    I have not seen the "9 out of 10 doctors say smoking is good for you" argument for a while (it only works when you select up front the right 10 doctors of course).

    NoTricksZone would be more persuasive if they selected the 133 papers at random. The 97% consensus allows for 3% of papers that disagree with the consensus, so there are bound to be some. And nothing wrong with that, as long as they are credible studies.

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  68. Richard Mallett.

    I picked a study at random: "Cloud effects on surface energy and mass balance in the ablation
    area of Brewster Glacier, New Zealand"

    http://www.the-cryosphere.net/10/313/2016/tc-10-313-2016.pdf#sthash.BMXWtI2v.rhxxpMIC.dpuf

    It does not dispute the consensus. Actually it does not even mention the consensus.

    I think NoTricksZone is trying to deceive it's readers.

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  69. David In Cal.

    Is it possible to convert the radiative forcing in the article into degrees of climate sensitivity? I have read elsewhere that the number is between 1 and 1.5 degrees C. Do you know if that's correct?"

    1-1.5C is the lower bound for estimates of ECS, I understand. The mean is higher, around 3C.

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  70. No Tricks Zone could not select 133 papers at random if there were only 133 papers in total. Much better to list and summarize the 133 papers so that readers can judge for themselves. The heading for the list is :-

    "Papers Supporting a Skeptical-of-the-Consensus Position for 2016" not specifically papers that mention the consensus.

    Does the fact that 133 sceptical papers were published in the first three months of 2016 (so an estimated 532 papers per year) mean that 532*97/3 = 17201 papers per year are published supporting the consensus ? That seems highly unlikely.

    A paper does not have to mention the consensus to be sceptical of the consensus.

    Regarding the Conway and Cullen paper at http://www.the-cryosphere.net/10/313/2016/tc-10-313-2016.pdf the conclusion states that :-

    "Given the frequent cloud cover at the site, cloudy periods accounted for a majority of the melt observed, especially during autumn when SWnet [shortwave] inputs were lower"

    and

    "Thus, it highlights the need to include the effect of atmospheric moisture (vapour, cloud, and precipitation) on both melt and accumulation processes when modelling glacier–climate interactions."

    I would regard that as sceptical of the position (oft repeated by the alarmists) that glacier melt is caused by anthropogenic warming.

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  71. I published a detailed reply, but it did not appear.

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  72. Richard, I've spent a considerable amount of time trying to explain to you why taking the derivative of the Hadcrut4 time series eliminates the long-term trend and accentuates the noise. As a method to understand climate extremes, anyone who knows anything about science or math would have quickly realized this is garbage. I've also spent a bit of time explaining to you one method on how to understand why temperature extremes rise at a phenomenal rate when the mean increases even by a little. Now you're asking questions that are just gibberish. It's clear I'm just wasting my time trying to help you understand basic concepts in math and physics.

    Harry, I also took a look at some of the papers listed on the NoTricksZone. One paper describes the decreasing albedo in the melting Greenland ice sheet, but attributes the decrease to a dark band of older ice rather than the light absorbing properties of aerosols. Perhaps Jason Box might disagree with that conclusion, but the paper does nothing to contest the consensus opinion. Rather, the article is picked out by the NoTricksZone because it mentions the sun. Yeah, like ice melt doesn't happen to peak during the summer months.

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  73. Not even Richard has been able to find a study in the list that disputes the consensus.

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  74. Richard says: "I would regard that as sceptical of the position (oft repeated by the alarmists) that glacier melt is caused by anthropogenic warming."

    No Richard. It is still widely understood that warmth does cause ice melt. This paper does not cast doubt on that consensus. At best it will improve model output which may help to address this discrepancy.

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  75. The paper on melting of the Brewster glacier states the following,

    "Given the frequent cloud cover at the site, cloudy periods accounted for a majority of the melt observed, especially during autumn when SWnet inputs were lower."

    This shows the cartoon understanding of climate science that Richard displays. What the paper shows is that there is increased downwelling short wave radiation during cloudy days that increases glacier melt. Apparently it never occurred to Richard that during the summer cloudy days are usually cooler because more short wavelength radiation is reflected. On the other hand, when more heat is transferred by convection rather than radiation, cloudy days are warmer because the clouds reflect the upwelling long wavelength radiation.

    Actually, the conclusions in this paper are so obvious I'm not even sure why it was publishable, except that the authors had a great deal of data to back up a rather obvious conclusion.

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  76. Correction to above:

    "What the paper shows is that there is increased downwelling short wave radiation..."

    should read,

    "What the paper shows is that there is increased downwelling long wavelength radiation ..."

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  77. Richard Mallett.

    You said: ""Papers Supporting a Skeptical-of-the-Consensus Position for 2016" not specifically papers that mention the consensus."

    You are a clown. How can they be "skeptical of the consensus" if they DO NOT even refer to the consensus, or contain anything RELEVANT to the consensus?

    But if you think I am wrong, then by all means review the 133 and point out where they are "skeptical of the consensus position". NoTricksZone have obviously not done this, so you would be doing them a favor.

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  78. Harry says: But if you think I am wrong, then by all means review the 133 and point out where they are "skeptical of the consensus position".

    Richard doesn't know what the consensus position is. He refuses to educate himself. He often references "alarmists" (whoever they may be... Wadhams I guess?). The mainstream science may be alarming, but by definition an alarmist is someone who is well outside of the consensus.

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  79. Reply to Harry Twinotter :-

    If I had the time to do that, you would just say (as you have done) that if they don't mention the word, then they don't disagree with the consensus, and therefore are not sceptical of the consensus.

    Reply to Layzej :-

    The consensus position is that :-

    a) Most of the warming since pre-industrial times (which could be any time from 1750 to 1970 depending on which person you talk to) has been anthropogenic.

    b) this warming is catastrophic / dangerous.

    I don't know who Wadhams is / are, but an alarmist is somebody who says that we have to do something to stop this (so-called anthropogenic) warming; and that even if we do, it will be centuries before we get back to a 'normal' temperature (whatever that is)

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  80. Richard,

    No Richard. An alarmist is "someone who is considered to be exaggerating a danger and so causing needless worry or panic". That could not include anyone who accepts the consensus position as outlined by the IPCC reports.

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  81. It is clear that Richard has no understanding of what the consensus opinion actually is. Rather than attempting to actually ascertain what that consensus is, Richard recites from the propaganda web sites.

    So now we also know that in addition to not understanding math and science, Richard doesn't understand basic logic. How can a consensus opinion be one in which the start date of anthropogenic warming depends on the person you talk to?

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