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Unforced variations: Jan 2020

Filed under: — group @ 1 January 2020

The new open thread on climate science for a new year, and a new decade – perhaps the Soaring Twenties? What precisely will be soaring is yet to be decided though.

Two things will almost certainly go up – CO2 emissions and temperatures:

But maybe also ambition, determination, and changes that will lead to reduced emissions in future? Fingers crossed.

503 Responses to “Unforced variations: Jan 2020”

  1. 51
    Mal Adapted says:

    Me:

    The rule of Ockham obliges whoever claims net reduced mortality to explain, for example, how a higher frequency of more intense tropical cyclones, and/or globally increased river flooding, might reduce casualties. Absent unsupported assumptions, parsimony suggests that an accurate enumeration of (total deaths caused) – (total deaths prevented) by AGW over the last 50 years, would show net mortality in at least the 100,000s.

    Dan H.:

    BTW, the rule of Ockham did not apply in this case, as I was not the one making an extraordinary claim. Rather, I was claiming the opposite. The onus rests on those claiming hundreds of thousands of excess deaths.

    For those of us who aren’t attribution experts, claims of 1000 to 100,000 excess deaths from the observed effects of rising GMST on global weather are confirmed, at least conditionally, by scientific meta-literacy. The reason Dan H. thinks a claim of hundreds of thousands of excess deaths is extraordinary, is that he’s a non-expert who lacks scientific meta-literacy. IOW, he’s an unambiguous victim of the Dunning-Kruger effect. That’s his problem, not mine. By insisting otherwise, he’s overpluralizing again – unless he counts himself among IAT, David Young, Victor and the rest of RC’s resident deniers, that is.

    Killian:

    What the hell do you think statistics are for?

    Yep. It’s worse than that, however: not only is Dan H.’s grasp of statistics inadequate, he doesn’t seem to understand how rising atmospheric CO2 results in increasingly extreme weather events, or why more extreme weather events are ceteris paribus more lethal!

  2. 52
    Mal Adapted says:

    Just so there’s no mistake: to a scientifically meta-literate person, “confirmed” in the empirical sense means “supported”. It doesn’t mean “proven.” Proof is for mathematics, US criminal courts and distilled beverages (sometimes the latter two combined); it is not for earth sciences or collective decarbonization choices (neither to be combined with distilled beverages).

  3. 53
    Mal Adapted says:

    MA Rodger:

    So we can billy-goat Victor’s trolling

    Dude, I like your style 8^)! Baa!

  4. 54
    jb says:

    Re: Victor (at 24) and Gavin’s response:

    Victor is a walking and talking example of why you cannot rely on the visual interpretation of a particular graph to characterize a trend. The apparent slope of a trend line (as opposed to the mathematical slope) is entirely dependent on the scale of the x and y axes. Here’s an experiment. If you plot the same trend and the same data twice, first in portrait mode (i.e., 8.5×11 on a letter size sheet of paper) and second in landscape mode (i.e., 11×8.5 on a letter size sheet of paper), the apparent slope of the trend line will be steeper on the portrait plot. Always. Victor likes to look at landscape plots of temperature, because they appear to confirm his bias.

    Victor’s a one trick pony. Maybe Gavin should put him to pasture.

  5. 55
    MA Rodger says:

    UAH have posted for December with the TLT anomaly of +0.56ºC, the second-highhest anomaly of the year and up fractionally on November’s +0.55ºC. 2019’s monthly anomalies came in between +0.32ºC and +0.61ºC, averaging +0.44ºC.

    December 2019 is the hottest December in the UAH TLT record, hottest by some way, sitting ahead of the El-Niño-boosted Dec 2015 which managed +0.47ºC, 2017 (+0.42ºC), 2003 (+0.38ºC), 1987 (+0.37ºC), 2016 (+0.27ºC), and 1998, 1997 & 2018 (all +0.25ºC).
    December 2019 is =10th highest anomaly on the all-month UAH TLT record. Of the ten anomalies equal or higher than Dec 2019, eight are from the super El Niño years of 1998 & 2016 with the other two from 2017 & 2019.

    So 2019 comes in as expected as 3rd place warmest-year in the trend-defying UAH TLT record. The top dozen years looks like this:-

    2016 … … +0.52ºC
    1998 … … +0.48ºC
    2019 … … +0.44ºC
    2017 … … +0.38ºC
    2010 … … +0.34ºC
    2015 … … +0.27ºC
    2018 … … +0.23ºC
    2002 … … +0.22ºC
    2005 … … +0.20ºC
    2003 … … +0.19ºC
    2014 … … +0.18ºC
    2007 … … +0.16ºC

  6. 56
    Jim Eager says:

    As Australia burns and the death toll rises former Prime Minister Tony Abbott insisted in an interview with the Israeli public broadcaster that the world is ‘in the grip of a climate cult’ :”
    https://www.theguardian.com/australia-news/2020/jan/03/tony-abbott-former-australian-pm-tells-israeli-radio-the-world-is-in-the-grip-of-a-climate-cult?CMP=share_btn_link

    He’s right, of course, but not in the way that he thinks. It’s the cult of fossil fuel interests and ideological AGW denial that has the world in its grip. It’s time to stop using the far too lenient term “denier” to describe Abbott’s and Morrison’s ilk and start using the more accurate term “climate criminal.”

  7. 57
    Ignorant Guy says:

    BPL @ 46 commenting on AB @ 32:
    “AB 32: “Climate” is an instantaneous value.

    BPL: No, it is not. It is the statistical average of weather over a large region or the entire world for 30 years or more.”

    In a sense the “average of weather over a large region or the entire world for 30 years” IS an instantaneous value.
    The newest such available is from NOW and 30 years back. That 30 year average can be updated in principle as often you want. And that latest update IS an instantaneous value.
    And OK, I realize of course that it is not REALLY available until it’s been calculated which takes some time, so it’s not really exactly from NOW – but it can still be updated as often you want.

  8. 58
    Ignorant Guy says:

    #24 Victor

    Hello there, Victor!
    Others have already answered this in rather technical ways but let me give you a really simple answer.
    When anyone, except you Victor, looks at those graphs the most striking thing that shows is how remarkably like each other they are. Actually they show (approximately) the same trend. When you fail to see that it’s because you stare yourself blind on two little wobbles, one up and one down. Two little wobbles around the trend.
    “Sixteen years of flatline followed by an abrupt rise lasting 2 years does NOT constitute a trend”
    YES, it does! You can’t throw away data you don’t like. And the trend is even more there if you also consider the years BEFORE your so called “flatline”. DON’T throw away good data. The more data you have the more you know. The less data you have the less you know.
    And if you trust NOAA it’s not just two years of steep rise. Your “flatline” lasts till at most 2014 – even if 2014 was a record hot year too – and after that ALL years, 2015, 2016, 2017, 2018 and 2019, have been considerably hotter.

  9. 59
    nigelj says:

    Al Bundys claim that climate is an instantaneous value seems to be confirmed by the study posted by KM @48.

  10. 60
    James says:

    Slioch (#8) said

    Meanwhile, little progress is made at COP because populations are electing leaders like Trump, Bolsanaro, Scott Morrison and Boris Johnston.

    I spoil the party by saying the election of Scott Morrison is the death knell, not so much because of him, but because a sample poll of 10+ million says people don’t understand and don’t care. They prefer the economic fairy story.

    [I hope I do not need to explain “fairy story” to this audience, but if I do we are heading for 3C by 2050 which NASA says “is incompatible with organized global community”, so what economy ?]

  11. 61
    David B. Benson says:

    Atlantic and Pacific oscillations lost in the noise
    2020 Jan 03
    Phys.org
    https://m.phys.org/news/2020-01-atlantic-pacific-oscillations-lost-noise.html

    What a shock! No more AMO or PDO according to M. Mann.

  12. 62
    Dan H. says:

    Mal,
    Not sure what you are playing at, but the sleazy lawyer trick might work among your feeble-minded friends, but it does not stand up to scientific scrutiny. You can try all the smear tactics you like, but lacking sound scientific data, your musings fall on deaf ears. Science is more than just name-calling and schoolyard bullying. Your crude attempts are pathetic, and anyone here can see that.

  13. 63
    nigelj says:

    Sure you have to be cautious eyeballing graphs, and confirm things with maths, but the positive warming trend after 1998 is pretty obvious by eye to me. Its a bit slower, but not subtle and certainly not ‘flat’.

    If deniers like Victor insist we remove the troubling 2015 el nino, then you would have to do the same for other el ninos going back, and you still get left with a strong warming trend. That must really make them cry in their beers.

  14. 64
    nigelj says:

    To be clear, the warming trend is a little bit slower around 2002 – 2006.

  15. 65
    Sam Kinder says:

    Hey guys, I’ve been having a look online and thought this might be a good place to ask the experts. Are there any responses to Willson and Scafetta’s 2019 paper on the ACRIM composite, and their contention that it is superior to the PMOD composite? It’s a pretty, um, aggressive paper, pretty much flat-out calling the PMOD team liars, albeit in nicer science-type talk. I figure people in the know about solar irradiance and its affect on the climate might have some comments on it, I’m a total novice at this stuff.

    Paper is here, for those interested: https://www.hindawi.com/journals/aa/2019/1214896/

  16. 66
    Mr. Know It All says:

    53 – Mal Adapted
    “MA Rodger:

    So we can billy-goat Victor’s trolling

    Dude, I like your style 8^)! Baa!”

    Not familiar with the term, I made the mistake of looking it up. Which definition were you two referring to?

    https://www.urbandictionary.com/define.php?term=Billy%20Goat

  17. 67
    zebra says:

    #51 Mal Adapted,

    I think Dan H is talking about some imaginary “rule of Ockham”, not Ockham’s Razor… a good example of a discussion where people haven’t agreed on essential stuff before they start disagreeing.

    That said, I’m not sure that OR is formally useful here, because you are evaluating a hypothesis, not two competing Theories.

    You are correct, of course, that he would have to provide causal propositions for reduced mortality attributable to ACC, and quantitative results, to support his claim. And, obviously, he can’t.

    (Just a brief opinion from the Philosophy-of-Science Nit-Pick Bureau.)

  18. 68
    Bruce Tabor says:

    I would dearly like your collective opinion on this paper:
    Sippel S 2020, Nature Climate Change, Climate change now detectable from any single day of weather at global scale
    https://www.nature.com/articles/s41558-019-0666-7.epdf

  19. 69

    VG 50: Anyone can draw a line between two endpoints and call it a trend.

    BPL: That’s not how you find a trend. You find a trend by doing a linear regression of the variable of interest on elapsed time. If the coefficient of your variable is statistically significant and positive, you have a rising trend, if significant and negative, a falling trend, if not significant, no trend. But you do not depend on two endpoints alone, ever. That will give you an F on your answer in any data analysis class.

  20. 70

    I have a statistics tutorial on my web site as part of what I call “the Intellectual Survival Kit.” Here’s the page on linear regression:

    http://bartonlevenson.com/ISK/Statistics/04Regression.html

  21. 71
    Geoff Beacon says:

    CMIP models

    A few years ago scientists at the UK Government department, DECC, told me

    1. Am I correct in thinking that some of these feedbacks were not used in the models that calculated the “remaining carbon budgets” – as used in the IPCC AR5? [That’s the CMIP5 models]

    That’s correct, the models used vary in what they include, and some feedbacks are absent as the understanding and modelling of these is not yet advanced enough to include. From those you raise, this applies to melting permafrost emissions, forest fires and wetlands decomposition.

    I have been told some of CMIP6 models do include these feedback effects. Is there a succinct summary of this progress.

    Wildfires
    Recently Copernicus.eu have asked Did 2019 really bring us an unusual number of wildfires? and said:

    In total, 6.735 megatonnes of carbon dioxide were released into the atmosphere by wildfires between 1 January and 30 November 2019. This value fits with the gradual declining trend in global total fire emissions since 2003, related to changing land management practices and use of fire in the tropics.

    (Being data only up to 30th November 2019, the “gradual declining trend in global total fire emissions” may be outdated.)

    For me this raises an interesting question about climate models. Consider

    1. Climate change increases the propensity of wildfires through local droughts and weather conditions.

    2. “Land management practices and the use of fire in the tropics” decrease the global total fire emissions.

    Wildfire questions:

    What sort of “land management practices” is meant here?

    How do climate models separate these two effects?

    If they are separated, what policy lessons can be learnt?
    e.g. Does it help to cut down forests so they cannot burn? &etc.?

    Other feedbacks
    Any other important feedbacks missing?

  22. 72
    Killian says:

    RE: The temp graphs: Somebody please explain to these #EcoNuremberg-headed liars surface temps do not equal global temps, and that any land “pause” was merely ocean heat/energy storage.

    There was no pause.

  23. 73
    CCHolley says:

    Re. Victor @24

    The arrogance of the stupidity.

    How Victor, a musician with zero scientific training, thinks he can possibly know more about climate science than a world renown professional climate scientist who lives and breaths this stuff everyday and attempt to reprimand said scientist on the science is beyond comprehension. Sad really.

  24. 74

    You can argue all you like about this graph , that graph, that difference etc. Unless someone is lying there (I believe Gavin) seems to be one hell of a storm going on out there. Considerable numbers of small lochs, lakes and ponds in Scotland have tended to go “green” for three years in a row now. Maybe we need to actually start on what we intend to do to repair the ecological damage. I most certainly do not wish to be in many parts of Australia once it starts raining. There was little enough action last time I was there, over 15 years ago and it was burning then, to hold the top-soil together. Sheet erosion is going to be the order of the day unless some one gets out there and starts to get some engineered repair and defense work done to slow down water flows. It’s a bit late for “nature” to heal itself.

  25. 75
    cctpp85 says:

    Yes, it does constitute a trend, but there are important trends to communicate and negligible ones. We often hear the magic phrase “there is a positive/negative trend” or simply draw a trend line. To be fair, we do not really care about the sign of the trend if it does not reveal an important background signal. We are not talking about significance but importance: is it larger than model guesses? is it fast enough to overcome our current management systems? All of this will be probably more visible in the next IPCC reports. Note the difference with trade analytics where any, even small, positive trend means “more $$$$$$”.

    “BPL: No, it is not. It is the statistical average of weather over a large region or the entire world for 30 years or more.”
    If you compute this average for every date, then the average becomes a continuous function with time, with an instantaneous value..
    In practice, any relevant background signal is called the climate signal and it is most of the time a continuous definition. It fits very well with the principle of signal decomposition which conserves continuity for every component.

  26. 76
    Slioch says:

    #31 Mr. Know It All says:

    “8 – Sliloch(sic) [it’s Slioch, Gaelic for Spear, as in Blake’s Jerusalem]
    “Please consider spending a little time every month wading through the swamp and educating a few frogs.”

    Please go ahead and educate away.”

    I am already doing so, and have been doing so on an almost daily basis for the last fourteen years, with precious little help from any of the good folk on RealClimate, most of whom are considerably more knowledgeable and competent on the subject than I am. Though I do so under another name, initially due to a registration error. But I’d had enough “We know were you live” threats under Slioch that I had no incentive to correct the mistake.

  27. 77
    b fagan says:

    Victor #24 – You claim zero trend in temperatures, per NOAA data, from 2000 to 2016. Then you posted a graph with no trendlines.

    Yet NOAA data shows a trend of +0.20°C/decade between 2000 and 2016. Sixteen years of trend surrounded by many more years with trend IS a trend, sorry.

    https://www.ncdc.noaa.gov/cag/global/time-series/globe/land_ocean/ann/11/1880-2019?trend=true&trend_base=10&begtrendyear=2000&endtrendyear=2016

  28. 78
    b fagan says:

    Guest (O.) #19 – regarding “Rex J. Fleming: The Rise and Fall of the Carbon Dioxide Theory of Climate Change”, it still appears on Springer’s site, but when you click any chapter for an overview, the site reports just the following terse message: “The rights of this book have been reverted back to the author.”

    The rise and fall of bad science?

    One sign – he has a podcast on anti-regulatory pressure group Heartland’s site, explaining that climate change is just the sun and cosmic rays (which just happen to have suddenly behaved far differently at the same time CO2 concentrations are jumping rapidly). Heartland helpfully advises “we must not stop using” fossil fuels. That’s some of the funding from coal millionaire Robert Murray at work. A recent NYTimes article documented his donations from files examined during a bankruptcy proceeding for his coal company.

    Author Fleming would also have to account for the actual measured change in IR from measured change in CO2 concentrations over a decade.
    “First Direct Observation of Carbon Dioxide’s Increasing Greenhouse Effect at the Earth’s Surface
    Berkeley Lab researchers link rising CO2 levels from fossil fuels to an upward trend in radiative forcing at two locations”

    https://newscenter.lbl.gov/2015/02/25/co2-greenhouse-effect-increase/

  29. 79
    Mal Adapted says:

    I’ll wade into the climate vs weather wrangle.

    I don’t think AB’s claims “Climate” is an instantaneous value and The 30 year climate rule of thumb is a dinosaur are preposterous, although the latter was a little hyperbolic. If we think of climate as the average weather within a (choose length) sliding window prior to the current instant, then yes, climate has an instantaneous value. And while it seems the 30-year rule of thumb is not extinct, it’s not the only salient interval either. Dan‘s link @30, to the National Climatic Data Center at the US NOAA, is good: Defining Climate Normals in New Ways. Dan quoted that unsigned page, presumably representing the institutional view:

    So, our scientists have traditionally defined Normals as averages over 30 years simply because that is the accepted convention—not because a 30-year average is the only logical or “right” way to define a Climate Normal.

    The page announces the release of Supplemental Monthly Temperature Normals (my bolding):

    Some users of our traditional Climate Normals products have expressed concerns about using a 30-year average in an era of observed climate change. Why? Because if climate conditions are shifting upward or downward, rather than fluctuating above and below the same constant level, it may make sense to calculate an estimate of the current state of the climate in a different way. Based on extensive feedback from user groups, particularly from the energy industry, we are now releasing Supplemental Monthly Temperature Normals that define “normal” in alternative ways.

    What Information Do Supplemental Monthly Temperature Normals Provide?

    Some of the new calculations are what you might expect: averages over 5-, 10-, 15-, and 20-year periods. We also compute “normal” in two additional ways: the Optimal Climate Normal (OCN) approach and the Hinge Fit approach. We won’t get into the heavy statistical details here, but you can think of the OCN as a “smart” average where the data values tell you how many years to average over. The Hinge Fit is a different animal altogether—in fact, it’s not even an average but a statistical fit through the data values. Generally speaking, the Hinge Fit is relatively sensitive to recent shifts upward or downward versus the 30-year normal, while the OCN reflects the effects of recent shifts more moderately.

    Also: once we’ve conservatively established a trend to the present, we have an “informed prior” for change-point analysis of shorter periods of interest using a null hypothesis of “no change in trend”, and for modeling future warming:

    Here, the main assumption is that past observed changes attributable to anthropogenic forcing can be used as a constraint to future warming.

    Our informed prior expectations are crucial for timely collective action. A 2013 working paper for the US EPA cited prior work:

    The importance of including low probability but potentially high impact catastrophic events in an economic modeling framework was initially informed by the theoretical work of Cropper (1976). She considers the generic case of a stock pollutant whose buildup reduces social welfare in a continuous fashion up to the point where the stock crosses a threshold, at which time a discontinuity occurs and social welfare immediately falls to the level associated with subsistence consumption. While the level of the threshold is uncertain the decision maker has an informed prior. Within this setup she finds that the potential for a catastrophic event can cause the presence of multiple market equilibria, suggesting the potential existence of such events has strong policy implications.

    Tsur and Zemel (1996) were among the first to translate this theoretical framework to the case of climate change, with the stock pollutant representing atmospheric carbon, which through its impact on Earth systems could potentially lead to a catastrophic event…

    “Multiple market equilibria” – yah. We choose which to make real, one way or another.

  30. 80
    Mal Adapted says:

    zebra:

    That said, I’m not sure that OR is formally useful here, because you are evaluating a hypothesis, not two competing Theories.

    Well, maybe not, but formality is wasted on Dan H. anyway. IMHO, Occam’s (or Ockham’s) least hypothesis rule broadly applies to these two competing theories: either Dan H. (or some other DK-afflicted denier) is right and the peer community of climate experts is wrong; or vice versa. The latter theory is favored by OR, as it entails fewer assumptions than the former.

  31. 81
    Al Bundy says:

    Rob B: The strong policy trend is against mitigation. So what is realistic for adaptation?

    AB: Mass death. Perhaps we can limit it to most of humanity. You best hope that you’re in the fortunate 40-or-so%.

  32. 82
    Mal Adapted says:

    Mr. Ironically Agnosognosic Typist:

    Not familiar with the term, I made the mistake of looking it up. Which definition were you two referring to?

    You’re not just bigoted and paranoid, but puerile. Proud of yourself?

  33. 83
    Al Bundy says:

    DasK’s initial thought (that he/she intelligently took back): the new decade starts 2021. sorry, but this commonly accepted “mistake” bothers me to no end.

    AB: Ain’t humans quaint. We focus ever so intently on that which applies only internally. Yada Yada Who cares?

    Slioch: by those individuals who normally frequent relatively erudite platforms such as Realclimate to counter the misinformation and deception churned out by,

    AB: As if churning is the bestest response to churning. You’ll lose if you go down that path. There are far more self-made-morons than folks like you. For a clue, read patrick’s posts.
    ________

    Kevin M/26/27,

    I gots nothing to add. You nailed it.
    _________________

    Killian: Shut up, disgusting criminal.

    AB: Are you so stupid that you don’t understand that such outbursts erase every productive thing you say?

    BPL: BPL: No, it is not. It is the statistical average of weather over a large region or the entire world for 30 years or more. The state of the world’s temperature, pressure, rainfall, wind direction and speed, etc. at a given instant is global weather, not global climate.

    AB: Bull.The 30 year rule is based on ignorance. As ignorance decreases, the timespan decreases. If you know EVERYTHING about climate/weather then you can derive “climate” from a single second’s worth of data, as informed by 100,000 years worth of archival data.

  34. 84
    Mal Adapted says:

    Dan H.:

    Not sure what you are playing at, but the sleazy lawyer trick might work among your feeble-minded friends, but it does not stand up to scientific scrutiny

    Sheer bravado on Dan H’s part, as his scrutiny is in no way scientific. WRT any scientific question, it’s the claim he’s right and the experts are wrong that won’t stand up to scrutiny.

    I wish to make it plain I don’t consider Dan H. “feeble-minded”. He has evident verbal skills, and apparently at least a high school education, though obviously not in physical or social sciences. AFAICT, that merely exacerbates the Dunning-Kruger effect. I, for one, regard the DK effect as a moral affliction, rooted in the “sin”, or folly, of pride: its victims flatter themselves that their subjective biases are supported by reality, justifying any odious preconceived notions they happen to hold.

  35. 85
    Mal Adapted says:

    Russell:

    Exponential expectations have grown since warnings of several degrees C of 21st century warming began four decades ago, and only seven decades remain before the year 2100.

    Bayesians are beginning to wonder if the 2020’s will prove to be the 5th decade when, despitre universal lip service to rising rates of climate change, no one actually steps forth to bet on a decadal temperature rise of two tenths of one degree?

    Hmm, I make it eight decades until 2100. At the current 30-year GMST trend of 0.203 +/- 0.054 °C/decade (Berkeley Earth dataset), by 2100 we expect 1.6 °C of warming in addition to the 0.189 +/-0.035 °C/decade since 1980 (ibid.), or (another estimate) the 0.85 +/- 0.25 °C of total warming since the 1950s. I lost interest in gambling at age fourteen after losing $2.00, otherwise I might bet on that. What odds are those Bayesians offering? What about the spread ;^)?

    FWIW, I’d call >2 degrees of 21st century warming “several”. But what do you mean by “exponential expectations”? Did someone claim in 1980, in a peer-reviewed venue, that GMST would rise exponentially this century? Has the curve since 1980 actually been exponential? Where’s Tamino?

  36. 86
    Killian says:

    Killian: Shut up, disgusting criminal.

    AB: Are you so stupid that you don’t understand that such outbursts erase every productive thing you say?

    1. Are you so stupid to be such a hypocrite? You are no better. So, yes, you are.

    2. Are you so stupid as to keep engaging disgusting criminals and not call them on their criminality, thus continuing the longstanding false equivalence engaging them encourages? Why, yes, you are.

    3. Are you so stupid as to be exposed to thinking superior to your own and justify remaining ignorant/uninformed/suicidally maladapted just because of how someone talks? I.e., so stupid as to throw away the future of humanity bc you don’t like me? Why, yes, you are.

    Shut up unless you’ve something of use to say – which is never: Engaging criminal denial is not useful. Engaging foolish, unsustainable nuclear energy is not useful. Rattling on about your nonexistent engine is not useful.

    Be useful, not stupid.

  37. 87
    Victor says:

    #69

    VG 50: Anyone can draw a line between two endpoints and call it a trend.

    BPL: That’s not how you find a trend. You find a trend by doing a linear regression of the variable of interest on elapsed time. If the coefficient of your variable is statistically significant and positive, you have a rising trend, if significant and negative, a falling trend, if not significant, no trend. But you do not depend on two endpoints alone, ever. That will give you an F on your answer in any data analysis class.

    VG: Take it up with Gavin, Bart. He’s the one who drew that line, not me.

    #77
    bfagan: Victor #24 – You claim zero trend in temperatures, per NOAA data, from 2000 to 2016. Then you posted a graph with no trendlines.

    Yet NOAA data shows a trend of +0.20°C/decade between 2000 and 2016. Sixteen years of trend surrounded by many more years with trend IS a trend, sorry.

    V: The El Nino in question actually peaked in 2015, so the flat trend to which I referred ended at the outset of 2015, not 2016. Sorry for the confusion. The “trend” you found at the NOAA site includes the El Nino singularity, which makes it a trend only in a purely statistical sense, since a singularity can’t be part of a trend. And yes, Virginia, statistics can be misleading. In the words of mini-AOC: “Did you know that?”

    According to the trend calculator at Skeptical Science ( https://skepticalscience.com/trend.php ), the NOAA data for 1998-2015 shows a trend of only .098 per decade; Hadcrut4: .068; RSSv4.0 TTT: .007; UAHv6.0 TLT: -.041 (yikes!). That’s 16 years. As the man said, “you pays your money and you takes your choice.”

  38. 88
    Al Bundy says:

    AB 32: The 30 year climate rule of thumb is a dinosaur.

    BPL: Then submit a paper to that effect to a peer-reviewed journal and get it published.

    AB: Why bother? I’ve shoved you into a little box labeled “pencil pusher” with very little effort.

    Yep, pencil pushers have value but no coach is gonna put one on the varsity squad.

  39. 89
    Al Bundy says:

    Mal: merely exacerbates the Dunning-Kruger effect. I, for one, regard the DK effect as a moral affliction, rooted in the “sin”, or folly, of pride: its victims flatter themselves that their subjective biases are supported by reality, justifying any odious preconceived notions they happen to hold.

    AB: You’re ignoring fully half of DK. DK states that those who are capable generally deny their capability.

    Why do people focus on morons? As if they matter, eh?

  40. 90
    Karsten V. Johansen says:

    Some “small” events in Australia to reflect upon for the socalled climate sceptics (ignorants is a more precise expression) if they would or could:

    “New South Wales Transport Minister and Member for Bega, Andrew Constance — who has been defending his home against ember attacks — compared the South Coast fires to “an atomic bomb”.
    “I’ve got to be honest with you, this isn’t a bushfire, it’s an atomic bomb,” he told ABC Radio Sydney.

    “It’s indescribable the hell it’s caused and the devastation it’s caused.””

    https://mobile.abc.net.au/news/2020-01-04/nsw-bushfires-rfs-issues-emergency-warnings-amid-dire-weather/11840524?

    All I know about the for now about three months ongoing catastrophe in Australia (and that’s a lot) points to this minister for one being right. And that’s a small stream of light in a deeply sleeping public. This catastrophe has not emerged out of the blue, far from, it’s the highly predictable result of over twenty years of complete, planned and calculated ignorance:

    https://www.theguardian.com/australia-news/2020/jan/02/2019-australia-hottest-year-record-temperature-15c-above-average-temperature

    It must be looked upon on the backdrop of fx. this scientific prognosis from 2013:

    “By 2020, the global land area experiencing temperatures of 3-sigma or more will have doubled (covering ~10%) and by 2040 quadrupled (covering ~20%). Over the same period, more-extreme events will emerge: 5-sigma events, which are now essentially absent, will cover a small but significant fraction (~3%) of the global land surface by 2040. These near-term projections are practically independent of emission scenario.”

    It was a very precise prediction, we now know. https://www.bbc.com/news/science-environment-49753680 And here is the prognosis for the european summer 2020, right after two exceptionally hot summers:

    https://m.youtube.com/watch?v=K662EYYNvpk

    Therefore, the prognosis from the same article about our near future has to be taken with the deepest possible sincerety:

    “The rise in the frequency of extremes becomes strongly dependent on the emission scenario only by mid-century. Under the low emission scenario (RCP2.6) (big emmision cuts, by todays politics less than pie in the sky, my comment, KJ), the number of extremes stabilizes at 2040-levels. This implies that in the tropics, including South America, western Africa and the Maritime continent, 3-sigma heat effectively becomes the new norm (about 50% of summer months, see figure 3) and 5-sigma heat will be common (about 20% of summer months). In the extra-tropics, 3-sigma extremes will also increase, occurring for example in western Europe in roughly 20% of summer months, but 5-sigma events will still be essentially absent. In the southern hemisphere, the increase in monthly heat extremes is essentially independent on the season. (…)”

    https://iopscience.iop.org/article/10.1088/1748-9326/8/3/034018

    Under the by far most probable scenario, business as extremely usual, the situation gets more than just apocalyptic:

    “Under the high-emission scenario (RCP8.5), the area of land experiencing 3- or 5-sigma events grows by roughly 1% yr−1 after 2040. By 2100, 3-sigma heat covers about 85% and 5-sigma heat about 60% of the global land area. The occurrence-probability of months warmer than 5-sigma reaches up to 100% in some tropical regions. Over extended areas in the extra-tropics (Mediterranean, Middle East, parts of western Europe, central Asia and the US) most (>70%) summer months will be beyond 3-sigma, and 5-sigma events will be common.”

    Meaning collapse in global foodsupplies etc.

    But Trump & co. (in reality by far most leading politicians) don’t think this is bad enough. They are pushing all red buttons they can, to worsen everything as much as they just can:

    https://edition.cnn.com/2020/01/04/politics/trump-warning-iran-52-assets/index.html

    The goal: to pump even more oil…and burn as much as possible in a new war. Where is Bernie Sanders?

    Not very surprising, his response just nearly totally wiped out by all the big media and most of the small by our socalled freedom of expression:

    https://m.youtube.com/watch?v=Ahv4nYd6fLI

    In reality we already live under a regime of total war and censorhip. Which was being rutinely enforced already for years when Ronald Reagan came to power by making dirty deals with the iranian ayatollahs 1979, to oust Jimmy Carter. What we have had since is democrazy, not democracy. Now we are beginning to pay the full price, and that’s an offer we are not even allowed to try to refuse.

  41. 91
    obn says:

    A naive question: the site http://www.temperature.global/ pretends to compute on the fly the earth global temperature
    “Temperature.Global calculates the current global temperature of the Earth. It uses unadjusted surface temperatures. The current temperature is the 12M average mean surface temperature over the last 12 months compared against the 30 year mean. New observations are entered each minute and the site is updated accordingly. ”
    It also lists the average temperature of the previous years

    “Previous Years

    The recorded global temperature for previous years:
    2015 average: 0.98 °F (0.54 °C) below normal
    2016 average: 0.48 °F (0.27 °C) below normal
    2017 average: 0.47 °F (0.26 °C) below normal
    2018 average: 1.33 °F (0.74 °C) below normal
    2019 average: 0.65 °F (0.36 °C) below normal”

    Why is this ? Is it because more and more cold stations are included ? Apologies if this question has already been answered but a search over http://www.temperature.global leads to too many answers.

    [Response: I emailed them when they started to get some info on their methodology and who they were. I did not get any useful information. The issues probably relate to inhomogeneities and inconsistent areal distribution of stations. But since they don’t show their working we have no real idea. If you want up to the minute (or close) estimates from the reanalyses are much better (and understood). – gavin ]

  42. 92
    MA Rodger says:

    b fagan @78,
    Yrespond to Guest (O.) @19 pointing out that the detail of the nonsense apparently being set out in the denialist book Fleming (2019) ‘The Rise and Fall of the Carbon Dioxide Theory of Climate Change’ isn’t available on-line.
    Do note the similarity of the book’s ‘fly jacket’ blurb and the abstract of ‘An Updated Review a bout Carbon Dioxide and Climate Change’, a work by the same author of the year before. Authorship and timing suggests that there won’t be a great deal of difference in the arguments presented in the two, perhaps a few more bells & whistles in the 145-page book than in the 16-page article. And the 2018 article is available on-line, concluding:-

    “The calculations of Section 5 revealed that there is no net impact of CO2 on the net heating of the atmosphere. The received heat is simply redistributed within the atmospheric column. This result is consistent and explains the lack of CO2 correlations with observations in the past.”

    We can ignore his silly “lack of CO2 correlations” analysis. The guts of Fleming’s thesis is that he finds CO2 acting as a GHG gas at sea level but finds it to be transparent at 9km and 17km altitudes. For me, that raises two questions – (1) Why didn’t he find the GHG effect of CO2 at and above 9km altitude with his many tens of thousands of ‘lines’ when MODTRAN with a couple of thousand ‘lines’ demonstrates a CO2 radiative effect all the way up to 40km? (2) Where does he calculate the effect of varying atmospheric CO2 concentrations?
    Indeed, the whole methodology employed by Fleming demonstrates that the muppet doen’t in any way understand the mechanism he is attempting to analyse. So it should come as no surprise to find that the idiot is simply spoutng denialist nonsense.

  43. 93
    Barton Paul Levenson says:

    AB 83: The 30 year rule is based on ignorance.

    BPL: No, it is based on a statistical procedure, which I outlined for you but you ignored.

    AB: As ignorance decreases, the timespan decreases. If you know EVERYTHING about climate/weather then you can derive “climate” from a single second’s worth of data

    BPL: No, that’s weather, not climate.

  44. 94
    zebra says:

    #79 Mal Adapted (also Al Bundy),

    First, Mal, of course I agree with #80.

    But my question about the 30-year thing is… what question are we answering?

    #61 from DBB is very interesting. But the analysis does what…confirm that aerosols have an effect? And, referring back to the Ockham thing: That what we observe isn’t the result of some complicated interaction of yet-to-be-even-postulated physical phenomena that we can’t detect? Well duh.

    And what can we do with shorter-term predictions? AB, do you think somehow this kind of sophisticated analysis is going to stop the Aussies committing mass suicide because they can’t let go of selling coal?

    It’s like some of the attribution stuff; it may be worthwhile as scientific investigation, but it doesn’t change any bottom lines as far as I can tell.

  45. 95
    Radge Havers says:

    # 84 Mal
    re D-K effect

    I think it’s a natural feature (bug) for humans to start out naive with poor, self-serving heuristics. It’s natural enough to out grow it in the proper environment; but that’s hard to do if you’ve been weakly educated compared to being strongly propagandized. It’s not entirely a personal failing, it’s also a social disease, imo.

    Hate to say it, but Dan H. is a lost cause. How many years has he spent here impervious, repeating the same tired b.s. word games over and over and over?

  46. 96
    Guest (O.) says:

    @zebra, #67: can you please explain the difference between “rule of Ockham” and Ockham’s Razor?

  47. 97
    Guest (O.) says:

    @b fagan, #78: What does the phrase
    “The rights of this book have been reverted back to the author.”
    mean?

    For me it reads neutral as some kind of law issue regarding authorship… and the right to publish (e.g. author wants to publish on it’s own too).
    …but you write, as if it means, that this is a publisher’s way of rejecting some kind of bogus “science” (like retraction of scientific papers)?

  48. 98
    zebra says:

    #96 Guest,

    I’m not sure, but I seem to recall that people like Dan H attach the name of Ockham to a statement along the lines of “extraordinary claims need extraordinary proof”. But that has nothing to do with Ockham’s Razor.

    The current Wikipedia article does a good job of explaining OR. My comment to Mal was just to point out that he was conflating what he correctly says at #80 with the specific hypothesis about the “number of deaths” question.

    If you still have a question after reading the Wiki article, let me know.

  49. 99

    #87–

    Victor, you are quite frankly pathetic.

    1) Primarily, 15 or 16 years is too short a period to reliably show the anthropogenic signal–this, we have discussed many, many times. (The literature reference is, IIRC, Santer et al 2010.) You’re trying to revive a very tired zombie cherry-pick.

    2) Secondarily, the trend from 2000 to 2015 *isn’t* flat, contra your description:

    …the flat trend to which I referred ended at the outset of 2015, not 2016.

    Woodfortrees doesn’t have NOAA data, but its trend is pretty reliably between GISTEMP and HadCRUT 4. They’re plotted here:

    http://woodfortrees.org/plot/gistemp/from:2000/to:2015/plot/hadcrut4gl/from:2000/to:2015/plot/gistemp/from:2000/to:2015/trend/plot/hadcrut4gl/from:2000/to:2015/trend

    If you check ‘raw data’, which gives the regression slope, you’ll find that GISTEMP shows a trend of ~0.12 C/decade, while HadCRUT clocks in at 0.08 C/decade. NOT flat.

    It’s not flat for 2000-2014, either. Or -2013. Or -2012. Or -2011. Or -2010. Or -2009. Or -2008. Or -2007. Or -2005. Or -2004. Or -2003. Or -2002. Or–

    No, wait, 2001 actually was colder than 2000!

    http://woodfortrees.org/plot/gistemp/from:2000/to:2001/plot/hadcrut4gl/from:2000/to:2001/plot/gistemp/from:2000/to:2001/trend/plot/hadcrut4gl/from:2000/to:2001/trend

    Jesus, you’re not even a very good cherry picker.

  50. 100
    nigelj says:

    Killian @86 saying to denialists “shut up you disgusting criminal” wont shut them up in the main, it will harden their attitudes. Does name calling make you change your mind?

    You are really just expressing your frustration. Denialists are seriously frustrating people, and are indeed putting the well being of the planet at risk.

    Its also inaccurate because this thing is not about law breaking as such. Maybe it should be but it isn’t.

    Many people will find your comments over the top, and they may sympathise with the denialists. Notice how lobby groups are usually quite polite in discourse.

    Tons of psychological research attests to all this.

    There are other put downs that are a bit more subtle, but are just as cutting. Humour helps.