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Unforced Variations: Jan 2021

Filed under: — gavin @ 1 January 2021

According to the somewhat* arbitrary customs of our age, the 1st of January marks the beginning of a new year, a new decade and, by analogy, a new start in human affairs. So shall it be at RealClimate too**.

This month’s topics will no doubt include the summaries of the 2020 climate (due Jan 14th or so), ongoing efforts to understand and predict extreme weather in a climate context, and the shift by the weather organizations (WMO, NWS) to a new set of climate normals (i.e. moving from 1981-2010 to 1991-2020).

In the spirit of this new year, please make a renewed effort to stay vaguely on climate science topics, try to stay constructive even when you disagree, refrain from posting abuse, and don’t bother with cut-and-paste climate denial (that stuff was tedious enough when it was originally wrong, and is simply boring now). Thanks!

*completely

**Seriously, we are thinking about how to update/re-position this blog, and would welcome constructive suggestions from readers.

258 Responses to “Unforced Variations: Jan 2021”

  1. 101

    JDS 88,

    Richard Lindzen is the author of a failed hypothesis called the “infrared iris,” which he first proposed, if I remember correctly, in 1982. It was shot down by satellite observations. He proposed it again in 1992, and again it was shot down. Then he did the same thing in 2002. Citing his accomplishments may be impressive, but it doesn’t negate the fact that the man has become a crackpot. He can’t let go of his wrong theory, and he resents the whole climatology world and all his colleagues because they won’t support it. There’s a name for this: Emeritus disease. Other examples would be Halton Arp and Thomas C. van Flandern in astrophysics.

  2. 102
    zebra says:

    Piotr #75,

    Piotr, we’re getting there. But just as you want to be sure people get that ocean chemistry analysis, the issue of better use of language is my “thing”.

    If someone asks me “is climate chaotic?”, my response is: What do you mean by “climate”?

    The term “chaotic” is used to characterize systems, in which non-linear elements are interacting with various degrees of coupling. So when you fall back on GMST as an example of something predictable, therefore not chaotic, it doesn’t tell us anything about the climate system… it is simply a proxy for the energy in the system.

    My understanding of the climate system is that we take an average in time (say 30 years) of each of the elements of the system. So, we do that for 1950-1980. Now say we compare that to 2010-2040.

    Would you not agree that, given the change in energy content of the system that resulted from human activity, we will discover that the elements of the system will have departed from their original 30-year average to one degree or another? And would you not also agree that eventually, it would be possible for the configuration of the system (i.e. the coupling) to enter a new equilibrium state?

    How does that not fit the definition of a chaotic system?

  3. 103
    CCHolley says:

    RE. J. Doug Swallow @88

    why I would go with what Richard Lindzen opinions are regarding this topic of the Earth’s ‘warming’.

    Too funny. A trial judge in Minnesota ruled that Lindzen was a non-creditable witness when it comes to expressing an opinion on climate sensitivity to CO2.

    STATE OF MINNESOTA
    OFFICE OF ADMINISTRATIVE HEARINGS
    FOR THE PUBLIC UTILITIES COMMISSION
    In the Matter of the Further Investigation into Environmental and Socioeconomic Costs Under Minnesota Statutes Section 216B.2422, Subdivision 3
    https://mn.gov/oah/assets/2500-31888-environmental-socioeconomic-costs-carbon-report_tcm19-222628.pdf

    IV. Equilibrium Climate Sensitivity
    22. The Administrative Law Judge concludes that Peabody failed to demonstrate, by a preponderance of the evidence, that an ECS value of 1 or 1.5 degrees centigrade is correct and that an ECS of more than 2 degrees centigrade is “extremely unlikely.”
    23. The Administrative Law Judge concludes that the preponderance of the evidence demonstrates that the ECS doubling ranges as reported by the IPCC in the IPCC AR4 (2.0-4.5 °C) and the IPCC AR5 (1.5-4.5 °C) are more accurate ECS ranges than the range advanced by Peabody because the IPCC ranges are representative of a comprehensive, peer-reviewed body of scientific study based on multiple lines of evidence.
    24. The Administrative Law Judge concludes that the preponderance of the evidence demonstrates the IWG had a reasoned basis to refrain from adopting the IPCC AR5 ECS values in the IWG’s 2013 FSCC update. While the IWG could have chosen to adopt the updated values at that time, it stated that it viewed that IPCC AR4 ECS values as the most authoritative at the time of the 2013 update and affirmed its intention to update the ECS values as appropriate in the future, based on the latest science and external expert advice.
    25. The Administrative Law Judge concludes that the preponderance of the evidence demonstrates that it was reasonable for the IWG to adopt the ECS range of 2.0-4.5 °C as stated in the IPCC AR4.

  4. 104
    J Doug Swallow says:

    MA Rodger should fill up a balloon with CO₂ and then he can observe what it does when it is released. Here is a free clue for him; it falls to the floor/ground, whatever. There is intelligent design because all of the living organisms that utilize CO₂ exist on the surface of the Earth.
    This below leaves no way to not understand that CO₂ is 1.6 times more dense than the rest of the Earth’s atmosphere.
    Abstract
    The catastrophic event at Lake Nyos in August 1986 has resulted in a major scientific debate concerning its origin and how to prevent new casualties of this nature in future. We have tried, in the present paper, to interrelate the testimonies in time and place, and to interpret them in geological terms. It has been possible to draw a hazard map of the catastrophe and reconstruct the sequence of the events. It began on August 20, 1986 with minor upwelling of hot water. On August 21, 1986, a small explosion occurred in Lake Nyos followed in the evening by an intermittent jet of water topped by a white plume. At 10 p.m. a major detonation occurred in the lake and carbon dioxide invaded the low lying valleys, killing more than 1500 people and 6000 head of cattle. The all scientific community agree: gases have a magmatic origin. Two scenarios have been used to describe the catastrophe: the volcanic origin scenario: a gas jet splitted across the lake water, and the limnic origin scenario: gases were stored in the lake water and an internal or external phenomenon triggered the degassing. In the volcanic origin scenario prevention of degassing is impossible, any volcanic area can present this danger in, or outside lakes; prediction will proceed with usual methods. In the limnic scenario both prediction and prevention are possible: the only dangerous area are located around lakes containing dissolved gases prevention can be obtain by pumping and degassing the deep waters to the surface. In the present paper, testimonies have been used to test both hypotheses.
    http://adsabs.harvard.edu/abs/1992JVGR…51..171L

  5. 105
    Ray Ladbury says:

    J. Doug Swallow, We would welcome an alternative view that didn’t consist in its entirety of an unpalatable mix of utterly refuted denialist talking points, held together by bullshit and leavened with a sprinkling of lies.

    Please. Up your fucking game!

  6. 106
    MA Rodger says:

    Mal Adapted @91,
    I think you’ll find up-thread that the idea of there being a “single” experiment as “the proof” of AGW was more a product of Chinese whispers than the original comment which less-strongly asked for “results of an experiment that presents empirical proof that CO₂ has something to do with the Earth’s temperature.” And a single instance of an experiment is never enough scientifically which at the least requires ‘repeatability’, this the original meaning of Aristotle’s famous statement “Μία χελιδὼν ἔαρ οὐ ποιεῖ.” Mind, many do see AGW as being one big and very dangerous experiment.

    As for your three-stage AGW argument, for the first “The world is warming”, you would of course have to be deranged to disagree, although there are plenty who would. And those denialists that do accept that temperatures are rising will do their damnedest to trivialize the level of the warming. Thus the Little Ice Age Revivalists, or Dickie Lindzen and his ‘thin red line’.

    As a result, many who say they agree that “the world is warming” do not really agree. Even Dickie Lindzen gets carried away and ends up lying about this. In his 2012 denialst rally in the UK Houses of Parliament (video here with this quote at about 32 mins) he said:-

    “Points to take away from the global mean temperature record.
    Changes are small. They are in the order of several tenths of a degree. Changes are not causal but rather the residue of regional changes. Changes in the order of several tenths of a degree are always present at virtually all time scales. And obsessing on the details of this record is more akin to a spectator sport for tea-leaf reading than a serious contributor to scientific efforts.
    Say, at least so far: if some day I should see some changes of twenty-times what I’ve seen so far, that would be certainly remarkable but nothing so far looks that way.”

    Skating over the bullshit content, what Dickie Lindzen is arguing is that a climatologist will ignore anything that does not change temperature by less than “twenty-time what I’ve seen so far.” With a +0.6ºC rise in global temperature in the previous 50 years, Lindzen is saying that less than 20 x 0.6ºC = 12ºC is unremarkable. For somebody purporting to be a serious climatologist, such comment is as delusional as those who deny there has been warming. Thus the “twenty-time what I’ve seen so far”, or the bit about being a serious climatologist, is one of the bare-faced lies Lindzen provides for his audience.
    (And for the record Dickie Lindzen is signed up to the fact that “CO₂ absorbs thermal heat” and also that CO₂ is the cause of the big bite out of the Earth’s IR signature at 666 Wavenumber, a point of proof that “CO₂ has something to do with the Earth’s temperature,”. This situation should be entirely understood by those who truly have “studied this topic of anthropogenic climate change for several years,” rather than those who fallaciously brag that they have).

  7. 107

    JDS now praises Tyndall to us, as if we’d never heard of him! Pretty funny, as John Tyndall’s name and work are quite familiar to most of us. In fact, I myself wrote an account of the same, here:

    https://hubpages.com/education/Global-Warming-Science-In-The-Age-Of-Queen-Victoria

    I’ve been encouraging JDS to “Start Here” to help him avoid some at least some gaffes. Here’s the direct link.

    https://www.realclimate.org/index.php/archives/2007/05/start-here/

    And it’s worth it, but there’s another resource close to hand as well. It may be found under the “Quick Links” Tab; the very first one, headed “AIP”, leads to Spencer Wearts’ “Discovery of Global Warming,” wherein Tyndall gets his due (and abundant ‘context’).

    Link: https://history.aip.org/climate/index.htm

    But Tyndall was shrewd enough to pretty immediately draw the appropriate conclusion from his lab work. I quote his own words:

    As a dam built across a river causes a local deepening of the stream, so our atmosphere, thrown as a barrier across the terrestrial rays, produces a local heightening of the temperature at the Earth’s surface.

    Which is as succinct, yet poetic, a description of the so-called Greenhouse Effect as you could ever wish for. Quite a bit better than the hackneyed “traps heat,” which is meant to convey the same idea, but does so with less exactitude (as well as less color.)

  8. 108

    #87, MAR–

    The funny thing about JDS’ aeronautical tale was that it nicely refuted his own point! If you recall, he was talking about taking off early at a high-altitude field in order to catch the cold, dense air of morning, which generates more lift.

    IOW, he was describing a sort of ‘natural experiment’ in which the temperature was driven by radiation, not by pressure/altitude. That is, of course, the exact opposite of the thesis he was trying to defend. (I.e., that pressure determines temperature.) But you don’t have to invoke high-altitude airfields: all you have to do is observe the fact that solar radiation drives temperature change regardless of atmospheric pressure. It’s literally everybody’s daily experience.

    It’s only a bit more observationally sophisticated to notice that surface temperature at night is also highly dependent on radiation: that is, the “terrestrial rays” of Tyndall’s quote (given in my comment above). Clear skies? You’re apt to see lots of overnight cooling. Low cloud? Not so much.

    And from those two observations, it’s not far to the notion that there just might be some sort of radiative balance…

  9. 109
    Russell Seitz says:

    104

    The Prandtl Number is not strong in this one.

    Maybe he should try agrobusiness:

    https://vvattsupwiththat.blogspot.com/2021/01/can-cowvid-masks-stop-coronavirus-and.html

  10. 110

    Mal, nice elaboration @ #91.

    Yes, “proof” hasn’t been the paradigm for a long time: Kuhn, falsifiability & all that.

    And one hallmark of crankery is the delusion that one can unilaterally impose the burden of proof on one’s opponent at will. This occurs in what the Canadian legal community has come to call “OPCA” cases–that’s “Organized Pseudolegal Commercial Argument.”

    OPCA involves a lot of essentially magical thinking, but particularly relevant here is the stratagem of attempting to make courts “prove” that they have jurisdiction, sometimes based on ridiculous notions regarding flags or symbols. Of course courts have none of it, but that apparently doesn’t stop so-called ‘gurus’ from preying on the gullible. Justice Rooke, who introduced this concept in a 2012 decision, countered denial of authority thus:

    *an OPCA argument that denies court authority cannot succeed due to the court’s inherent authority;
    *an OPCA argument that denies court authority is intrinsically frivolous and vexatious;
    *an OPCA argument that denies court authority may be contempt of court authority, [for example]:

    -denial of tax obligation evades tax;
    -denial of firearms restrictions proves intent for illegal possession;
    -denial of court authority may prove the intent to engage in contempt of court.

    https://ablawg.ca/2012/10/30/the-organized-pseudolegal-commercial-argument-opca-litigant-case/

    But while the OPCA arguments fail on their [de]merits, landing those so pleading in legal embarassment–just as JDS’s similar arguments fail, landing him in socio-scientific embarassment–OPCA can succeed in gumming up the wheels of justice–just, once again, as JDS is gumming up these threads.

    Despite Justice Rooke’s valuable efforts, the problem hasn’t gone away, despite partially successful mitigatory efforts. That led a scholar just last year to highlight “the real damage that abusive litigation can do to the justice system, and the need for novel solutions to nip such litigation in the bud.”

    https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3719526

    Of course, we in the US (and around the world) have just seen an example of vexatious argumentation/litigation playing out not only in our courts, but in media, society, and even the halls of Congress. The abandonment of reason in favor of rationalization is the very substance of America’s epistemological crisis.

  11. 111
    William B Jackson says:

    #104 JDS If ever you make sense it will cause massive reverberations here. The action of a balloon full of co2, floating or falling, in relation to the action of growing levels of said gas in the atmosphere on temperature of said atmosphere are related how?

  12. 112
    prl says:

    nigelj @94: So JDS are hottest year record reliable or not?

    The Australian Bureau of Meteorology says that the maximum for Australia in Cloncurry in 1889 that JDS quotes is not part of what it considers the reliable temperature record in Australia:
    To enable valid comparisons of extreme temperatures to be made, it is very important to have high-quality observations measured in a consistent way. Standards relating to the accuracy of the instruments, their exposure and the height (above ground level) at which measurements are taken have been in place for temperature since early in the 20th century. The Stevenson Screen became a national standard by 1910, but before then thermometers were sheltered in a variety of ways, sometimes resulting in the instrument being in direct sunlight.

    For these reasons only those records taken since 1910 are included in the tables of extreme temperatures.
    http://www.bom.gov.au/climate/extreme/records/about.shtml

    I’d expect that that comment applies to a lot of 19th and early 20th century temperature measurements outside Australia, too, especially if the measurements weren’t taken in Stevenson screens.

    The official Australian Bureau of Meteorology maximum temperature record is:
    50.7°C [123.6°F] 2 January 1960 Oodnadatta Airport, South Australia
    http://www.bom.gov.au/climate/extreme/records.shtml

    That’s about 4°F less than the Cloncurry 1889 value that JDS quotes.

    The screening of the Cloncurry thermometer in 1889 certainly had a distinctly Australian flavour:
    Climatologist at the Bureau of Meteorology Blair Trewin said not all readings survived scrutiny.

    Among the more famous not to make the record books was the 53 degree temperature taken in Cloncurry, in north-west Queensland, in 1889.

    “We found documentary evidence for that which showed the measurement was taken in – would you believe – a beer crate nailed to the side of a house,” he said. “That would certainly have affected the reading … which was probably somewhere around 47 degrees [Celsius].”
    https://www.smh.com.au/environment/hottest-temperature-on-earth-revised-20120914-25wji.html

  13. 113
    Piotr says:

    BPL(99) to JDS, about JDS’s ignorance of atmospheric PHYSICS :
    Until you understand the theory you’re criticizing, your critiques will be meaningless. You come off like a creationist talking about biology.

    And the Word became flesh and made His dwelling on RC: JDS have explained in (104) WHY CO2 is heavier than air: “ here is intelligent design because all of the living organisms that utilize CO₂ exist on the surface of the Earth” ;-)

    But wait, it gets better! To illustrate how benign and intelligent his Designer was, our JDS chose the example of: “ carbon dioxide invaded the low lying valleys, killing more than 1500 people and 6000 head of cattle.
    O, Hail this Intelligent Design!

    Meantime, somewhere above the clouds, the Designer hid His face in His giant hands. First Trump, now this… No wonder that He will be (again!) a butt of jokes during the next Intelligent Designer Symposium:
    Your design “JDS” said WHAT ????? [Homeric hilarity ensues]”.

  14. 114
    Western Hiker says:

    I discovered “Severe Weather Europe” just a few days ago. So instructive! A must read for amateur weather geeks like me. Here’s the latest:

    https://www.severe-weather.eu/global-weather/polar-vortex-collapse-winter-weather-europe-united-states-2021-fa/

  15. 115
    Piotr says:

    Zebra (102) says: Piotr #75, we’re getting there.

    Err, I don’t think so. If anything we are getting further apart:

    You: “ Would you not agree […] that the elements of the system will have departed from their original 30-year average to one degree or another? And would you not also agree that eventually, it would be possible for the configuration of the system (i.e. the coupling) to enter a new equilibrium state?

    This has _nothing_ to do with what I was saying: I never disputed _that_. The
    discussion is whether global climate is chaotic (=very sensitive to small changes in conditions, and therefore very difficult to predict) or not)

    – AMD (43) says “yes”: “ We know weather is chaotic and so must be climate.
    – I say “not” – because “global climate” – by averaging of local weathers over long-term (decadal) and spatial (long term) average – “averages out” the local weather chaotic fluctuations (i.e. over global and decadal scale these fluctuations cancel each other out).

    So in terms of your latest post – if the global climate changes – it will be because we put more GHGs in air, and this effect can be with some confidence estimated, but not because random local fluctuations for some reason stopped to be random, but moved the global decadal average into a “new equilibrium”.

    It’s like a coin toss. Outcome of an individual toss is – chaotic (dependent on tiny changes of how you tossed it) – the average outcome of 1000 tosses is NOT. _Because_ the 1000-toss average “averaged out” all these hard to measure tiny differences needed to predict individual tosses, and what is left is non-chaotic influence (say, is the one side of the coin heavier than the other). So, yes, the local weather is chaotic, but the global climate is not.

    And for this reason, I have more confidence in the predictions of global decadal temperature in 2100, than in the forecast of my local temperature on the day 4 weeks from now.

  16. 116
    prl says:

    JDS @104, apparently quoting the abstract of Le Guern, Shanklin, Tebor; Witness accounts of the catastrophic event of August 1986 at Lake Nyos (Cameroon) (I say “apparently”, because the link is broken):
    This below leaves no way to not understand that CO₂ is 1.6 times more dense than the rest of the Earth’s atmosphere.

    … At 10 p.m. a major detonation occurred in the lake and carbon dioxide invaded the low lying valleys, killing more than 1500 people and 6000 head of cattle. …

    Simple question: What is the CO2 concentration around Lake Nyos now, and why?

    A hopefully non-broken reference:
    https://ui.adsabs.harvard.edu/abs/1992JVGR…51..171L/abstract

  17. 117
    nigelj says:

    J Doug Swallow @104

    “MA Rodger should fill up a balloon with CO₂ and then he can observe what it does when it is released. Here is a free clue for him; it falls to the floor/ground, whatever. ”

    A ballon will fall to the ground because the CO2 is concentrated and contained. When fossil fuels are burned it is not so concentrated and contained, so it disperses easily and most of it gets carried aloft by convection and turbulence even although its heavier than other gases. If CO2 emitted by burning fossil fuels or other sources stayed near the ground we would all be dead, or at least suffering permanent headaches and drowsiness. Even quite low concentrations can cause headaches and drowsiness. So obviously something causes the CO2 to become well mixed in the atmosphere. And of course sampling of the air by instruments in things like weather baloons finds CO2 is well mixed in the atmosphere.

    “It began on August 20, 1986 with minor upwelling of hot water. On August 21, 1986, a small (volcanic) explosion occurred in Lake Nyos followed in the evening by an intermittent jet of water topped by a white plume. At 10 p.m. a major detonation occurred in the lake and carbon dioxide invaded the low lying valleys, killing more than 1500 people and 6000 head of cattle.”

    This is a very high concentration of CO2 that stays near the ground for a limited period in certain conditions, like for example temperature inversions when the air is quite still, and in geography with lots of valleys. So of course it is lethal. You cannot reason from there that all CO2 stays near the ground.

    “There is intelligent design because all of the living organisms that utilize CO₂ exist on the surface of the Earth.”

    Good grief, thats such a crazy statement on so many levels its a bit of a jaw dropper. First he has let slip the essence of his climate scepticism. Probably something like god wouldnt let climate change happen, or its all natural and part of the ‘plan’ so the science must allegedly be bunk. Personally I think if theres a god then god would be horrified about what we are doing to the climate. Secondly what is the connection between organisms inhaling Co2 living on the surface and intelligent design (which doesnt actually exist)? Its rather tricky finding the logical connection. And thirdly what about plant life high up on the sides of mountains? How come they dont die, if all the CO2 is floating a few metres or so above ground level?

  18. 118
    nigelj says:

    Zebra @102, weather is much more chaotic than climate. There, fixed it for you.

  19. 119

    JDS 104: MA Rodger should fill up a balloon with CO₂ and then he can observe what it does when it is released. Here is a free clue for him; it falls to the floor/ground, whatever. There is intelligent design because all of the living organisms that utilize CO₂ exist on the surface of the Earth.
    This below leaves no way to not understand that CO₂ is 1.6 times more dense than the rest of the Earth’s atmosphere.

    BPL: Well, let’s do some math, JDS. Carbon dioxide is 0.04% of the atmosphere. The tropopause averages 11 km in height and contains 80% of the mass of the atmosphere. So by your reasoning, the lowest 4.4 meters of the ground above sea level should be pure carbon dioxide, and that should be topped by a lot more argon.

    How is it that people can breathe at the beach?

  20. 120
    Killian says:

    On Chaos:

    Gavin some years ago stated climate is not chaotic. To make it simple, he was basically saying it was nonlinear, not chaotic. I’ve also seen it described as semi-chaotic. My own stance is close to the latter. However, even if the physics is non-chaotic, human behavior is, and the primary driver of climate on Earth is human behavior, therefore, in the sense climate is utterly dependent on what choices humans make, climate is chaotic.

    [Response: It’s an open question as to whether the climate system as currently configured is in a practically chaotic regime. There’s more evidence of that in the glacial periods though one can’t rule it out completely. – gavin]

  21. 121
    Killian says:

    102 zebra:
    11 Jan 2021 at 7:53 AM

    Would you not agree that, given the change in energy content of the system that resulted from human activity, we will discover that the elements of the system will have departed from their original 30-year average to one degree or another? And would you not also agree that eventually, it would be possible for the configuration of the system (i.e. the coupling) to enter a new equilibrium state?

    How does that not fit the definition of a chaotic system?

    No. Any system can have a phase change based on very clear mathematics. A pile of sand will collapse at a specific angle (41 or 42 degrees,iirc). The collapse is predictable, not chaotic. That it collapses is not chaotic.

    What makes a system chaotic is 1. high sensitivity to small changes. A pile of sand is not sensitive to small changes, except at that very specific angle. 2. It’s unpredictable. We can confidently predict when the sand pile collapses. We cannot predict when a chaotic system will phase change. We cannot yet even easily identify when a phase change (bifurcation) is underway, though there has been some improvement in detection of wobbles.

  22. 122

    #119, BPL–

    Well, let’s do some math, JDS. Carbon dioxide is 0.04% of the atmosphere. The tropopause averages 11 km in height and contains 80% of the mass of the atmosphere. So by your reasoning, the lowest 4.4 meters of the ground above sea level should be pure carbon dioxide, and that should be topped by a lot more argon.

    How is it that people can breathe at the beach?

    Exactly. Once again JDS provides an illustration that actually disproves his contention: if CO2 behaved as he suggests, the outbreak at Lake Nyos would have resulted in the creation of a near-permanent ‘killing zone’. (Or maybe a moving disaster as the CO2 followed the topography downhill.) Instead, winds remixed the CO2 into the air, and in a relatively short time. JDS really is a careless thinker!

    A tasty, if perhaps gratuitous, analogy: the layered cocktail. The density differences of the various liquids enable the eye-catching layering, but the bartender who crafts one needs care and a steady hand in order *not* disrupt the stratification with too much turbulent pouring. It’s not a very stable configuration, and, well, entropy…

  23. 123
    zebra says:

    Piotr #115,

    Well, this is where I wanted to get. I wanted to establish that this is a ‘definition debate’, which is why I said I would first ask for clarification of what someone meant by “climate” to give an answer. (It would be great if AMD, whom you were answering, would let us know…are you there, AMD?)

    The point is that you agree with me that the climate system as I define it is chaotic, but you are creating a definition “global climate” which involves first averaging the metrics over space.

    Now, I think this is misguided, referring back to that post by Rasmus “thinking small and big”, and again your language reflects misunderstanding.

    You said “local weather is chaotic but global climate is not”. But Rasmus was talking about local climate. (As am I, here.) Maybe you didn’t read that post, but he was talking about making predictions for ‘regions’.

    (Let’s agree a region is some substantial geographic area with a characteristic climate. And by “regional climate”, I mean the average over 30 years for various metrics within that region.)

    So the problem with your “global climate” metric, as I said previously, is that GMST has no practical value except as a proxy for total system energy. Nobody cares that we can predict the GMST in the future with some confidence, unless you want to keep wasting time indulging the Denialists. We’re past that.

    What we care about is how the increase in energy manifests itself within the chaotic climate system… what we experience. Nobody experiences the global average over space, we experience the local/regional average over time… the local climate. That’s what the organization Rasmus was talking about is trying to predict.

    (And I think you have some misunderstanding of my use of “equilibrium state”… the system can still be chaotic, but with the elements existing in a new configuration. But that is some speculative future condition, if we continue to screw things up.)

  24. 124
    MA Rodger says:

    Barton Paul Levenson @119,
    If all the atmospheric CO2 were to pool at ground level, your estimate of the volume of CO2 as being 4.4m deep isn’t far off.
    At [410ppm(v) x 44/28.8 =] 626ppm(m) CO2 , the ten tons of air above a square metre of surface will contain 6.26kg CO2. The full ten tons results in a surface air density of 1.225kg/m^2 (although any warming from this level of compression would have long since vacated the planet as today’s air pressure has been in place for eons). If this surface air were all CO2 the density would be boosted by a factor of [44/28.8 =] 1.528 to 1.872kg/m^2 which would require a layed of atmosphere [6.3/1.872 =] 3.4m deep, this assuming a ‘flat’ surface.
    And above the CO2 would sit several tens of metres of argon.
    Of course, this ‘pooling’ doesn’t happen because Kevin McKinney’s bar tender described @122 has been a little shaky and the atmospheric gases are not contained in party balloons but are all mixed up. So buoyancy plays second fiddle to air movement which prevents any such ‘pooling’.

  25. 125
    Russell Seitz says:

    111:
    The action of a balloon full of co2, floating or falling, in relation to the action of growing levels of said gas in the atmosphere on temperature of said atmosphere are related how?

    In the fourth decimal place. at STP, or the fifth ,if you can get the ballon off the ground.

  26. 126
    Piotr says:

    Zebra (123)
    Zebra: The point is that you agree with me that the climate system as I define it is chaotic

    I don’t want to be difficult, but I don’t recall agreeing with it.

    Zebra: but you are creating a definition “global climate” which involves first averaging the metrics over space. Now, I think this is misguided

    I don’t, because the human act of calculating an average, has a real life equivalents – say, a river flow is a sum of the movements of all its water molecules – with each molecule velocity being a sum of flow downstream and random fluctuation due to interactions with other molecules, bottom or shoreline.
    But to the river flow these random fluctuation are irrelevant, since they cancel each other out – even though nobody has pulled out a calculator and CALCULATED an “average”.

    Zebra: You said “local weather is chaotic but global climate is not”. But Rasmus was talking about local climate. Maybe you didn’t read that post, but he was talking about making predictions for ‘regions’.

    Irrelevant, since I wasn’t talking about Rasmus. I questioned Alastair’s claim, I quote: “ We know weather is chaotic and so must be climate ” and from his examples, it is obvious that he wasn’t talking about “local climate”.

    Zebra: So the problem with your “global climate” metric, as I said previously, is that GMST has no practical value except as a proxy for total system energy. Nobody cares that we can predict the GMST in the future

    “No practical value”? That’s why so much work by the major climate centres to calculate the … irrelevant historic and present-day GSMT? That’s why climatologists evaluate the strength of various CLIMATE MODELS based on their ability to recreate the … irrelevant GSMT? That’s why the most important output of IPCC are their projections of … the irrelevant GSMT? That’s why their advice to the governments on needed emission cuts is based on the evaluating different scenarioes by comparing the GSMTs they will produce? And that’s why GSMT is the most important climate metric in most geological paleoclimate studies?

    After all, GSMT is ONLY “a proxy for total system energy“. Wait a minute, wasn’t it “the total system energy” what ultimately … drives the system?
    And aren’t the changes in “total system energy” (more energy absorbed than radiated out) what ultimately drives the “climate change” ?

    No practical value“, you say?

  27. 127
    AIC says:

    They’re climate scientists. They’re mothers. Now they’re joining the battle to get Americans to act

    Ad campaign featuring moms who are climate scientists

    https://www.latimes.com/environment/story/2021-01-12/mothers-are-increasingly-worried-about-climate-change-a-new-ad-campaign-has-female-scientists-speaking-directly-to-them

    Unfortunately, also attracting online comments from global warming deniers

  28. 128
    Mr. Know It All says:

    114 – Western Hiker

    Ah, yes, you were correct – severe winter weather in Europe.
    A brutal, existential threat to humanity, in the form of a snowstorm buries Spain!

    https://nypost.com/2021/01/11/madrid-rushes-to-dig-out-from-snowstorm-as-temperatures-plummet/

    Also, a dangerous snowstorm has paralyzed the Southern USA:

    https://people.com/human-interest/record-breaking-snowstorm-hits-southern-united-states/

    Your story was good, Western Hiker, but it appears as if they accidently mixed in mammograms in the graphics. That is weird! They did a fair job of predicting the weather though!

    For all who are caught in these dangerous winter storms, be safe, and be prepared!
    Ice Age Farmer on YouTube is getting more street cred!
    :)

  29. 129

    KIA 128: Ice Age Farmer on YouTube is getting more street cred!

    BPL: I imagine Youtube is where KIA gets most of his climate science.

  30. 130
    zebra says:

    Let The Definition Debates Begin,

    From Wolfram MathWorld (my bold):

    “Chaos” is a tricky thing to define. In fact, it is much easier to list properties that a system described as “chaotic” has rather than to give a precise definition of chaos.

    Gleick (1988, p. 306) notes that “No one [of the chaos scientists he interviewed] could quite agree on [a definition of] the word itself,” and so instead gives descriptions from a number of practitioners in the field. For example, he quotes Philip Holmes (apparently defining “chaotic”) as, “The complicated aperiodic attracting orbits of certain, usually low-dimensional dynamical systems.” Similarly, he quotes Bai-Lin Hao describing chaos (roughly) as “a kind of order without periodicity.”

    It turns out that even textbooks devoted to chaos do not really define the term. For example, Wiggins (1990, p. 437) says, “A dynamical system displaying sensitive dependence on initial conditions on a closed invariant set (which consists of more than one orbit) will be called chaotic.” Tabor (1989, p. 34) says, “By a chaotic solution to a deterministic equation we mean a solution whose outcome is very sensitive to initial conditions (i.e., small changes in initial conditions lead to great differences in outcome) and whose evolution through phase space appears to be quite random.” Finally, Rasband (1990, p. 1) says, “The very use of the word ‘chaos’ implies some observation of a system, perhaps through measurement, and that these observations or measurements vary unpredictably. We often say observations are chaotic when there is no discernible regularity or order.”

    So a simple, if slightly imprecise, way of describing chaos is “chaotic systems are distinguished by sensitive dependence on initial conditions and by having evolution through phase space that appears to be quite random.”

  31. 131
    mike says:

    “We report three major and confronting environmental issues that have received little attention and require urgent action. First, we review the evidence that future environmental conditions will be far more dangerous than currently believed. The scale of the threats to the biosphere and all its lifeforms—including humanity—is in fact so great that it is difficult to grasp for even well-informed experts. Second, we ask what political or economic system, or leadership, is prepared to handle the predicted disasters, or even capable of such action. Third, this dire situation places an extraordinary responsibility on scientists to speak out candidly and accurately when engaging with government, business, and the public.”

    https://www.frontiersin.org/articles/10.3389/fcosc.2020.615419/full

    or it could all be ok.

    There is a spectrum of thoughts on these matters.

    Mike

  32. 132
    Western Hiker says:

    MKIA, #128

    You’ve misunderstood my intent. Severe Weather Europe reads like meteorology 101 (or so I imagine, having never taken a coarse in meteorology). The links touched on extreme cold in Siberia and Mongolia, epic snowstorms in Japan. The sort of events you’ll find cherry-picked at IceAgeNow.

  33. 133
    zebra says:

    Piotr #126,

    “I don’t recall agreeing with it”

    #115:

    zebra:

    “ Would you not agree […] that the elements of the system will have departed from their original 30-year average to one degree or another? And would you not also agree that eventually, it would be possible for the configuration of the system (i.e. the coupling) to enter a new equilibrium state?”

    Piotr:

    This has _nothing_ to do with what I was saying: I never disputed _that_.

    OK, are you disputing it now? Or are you starting a new definition debate, by saying that such a system might not qualify as chaotic?

    If you have your own definition of chaotic system, let’s hear it.

    WRT Alastair, you say “it is obvious he wasn’t talking about local climate.” But again it is a silly definitions game; “local” could mean rain at my house, or it could mean ice-free Arctic Ocean, relative to “global”. The point, again going back to the Rasmus post, is that people are trying to “downscale”, and the degree of predictability is related to that scale. And it also matters what you are choosing to predict.

    WRT GMST, your little rant makes no sense. What I said is exactly correct, and you are not contradicting it… you are agreeing. It’s a proxy for the (change) in energy in the system (caused by human activity). Scientists plug that energy change into the models, and the models give useful predictions. GMST is an effect, not a cause, and people waste absurd amounts of time discussing it with JDS and the other nutjobs.

  34. 134
    nigelj says:

    This is ominous news: “Earth’s ‘lungs’ could start deteriorating in as little as two decades”

    https://www.stuff.co.nz/environment/climate-news/123931638/earths-lungs-could-start-deteriorating-in-as-little-as-two-decades

    Some of the world’s biggest forests might start losing their carbon-sucking powers in just a few decades, says a study by New Zealand and US scientists.

    We rely on plants to suck in a quarter or more of our fossil fuel emissions.

    But, unless we slow global heating, up to half the world’s forests and grasslands could pass their peak carbon dioxide uptake within the next two to three decades, according to a study in the journal Science Advances by researchers at Northern Arizona University (NAU) and the University of Waikato……

  35. 135
    nigelj says:

    zebra @133, (responding to piotr). Zebra doesn’t make much sense to me. The fact that the climate could depart from its average 30 year state and enter a new equilibrium looks more like a forcing than chaos theory. Climate probably has some inherent chaos, but is is not hugely sensitive to initial starting conditions and its reasonably periodic so its not categorised as a chaotic system. Weather is very sensitive to initial starting conditions and its periodicity is less regular so its considered chaotic. Surely these terms are relative and just shorthand notations?

    We have global, regional and local climates that can be defined enough to be useful. Its not remotely clear what Zebras point is. Zebra seems to consider Piotrs rant is senseless, yet Piotr is obviously disagreeing with Zebras statement “So the problem with your “global climate” metric, as I said previously, is that GMST has no practical value except as a proxy for total system energy. Nobody cares that we can predict the GMST in the future” and quotes some sensible sounding reasons why it is of practical value. Anyway I would just ask that Zebra clarify what he’s getting at with all this stuff.

  36. 136
    Killian says:

    Re 131 mike:

    I was about to post that myself. It fits perfectly with my call for a risk-based approach to both discussing climate science and, more importantly, the climate response.

    Things are worse than too many realize, even some scientists – as the paper and articles state.

    The time for this shift to occur in the climate dialogues is well past. We must change the conversation if we hope to change the trajectory we are on.

  37. 137
    Alastair McDonald says:

    I posed the idea that climate is chaotic partly to find out if anyone agreed with me. However, it is now clear that not only does everyone have their own definition of chaos they also have their own definition of climate!

    My definition of climate is that in wider sense in the IPCC glossary: https://www.ipcc.ch/sr15/chapter/glossary/

    Climate

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

    Climate system

    The climate system is the highly complex system consisting of five major components: the atmosphere, the hydrosphere, the cryosphere, the lithosphere and the biosphere and the interactions between them. The climate system evolves in time under the influence of its own internal dynamics and because of external forcings such as volcanic eruptions, solar variations and anthropogenic forcings such as the changing composition of the atmosphere and land-use change.”

    My definition of of a chaotic system is

  38. 138
    Alastair McDonald says:

    I posed the idea that climate is chaotic partly to find out if anyone agreed with me. However, it is now clear that not only does everyone have their own definition of chaos they also have their own definition of climate!

    My definition of climate is that in a wider sense in the IPCC glossary: https://www.ipcc.ch/sr15/chapter/glossary/

    “Climate

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

    Climate system

    The climate system is the highly complex system consisting of five major components: the atmosphere, the hydrosphere, the cryosphere, the lithosphere and the biosphere and the interactions between them. The climate system evolves in time under the influence of its own internal dynamics and because of external forcings such as volcanic eruptions, solar variations and anthropogenic forcings such as the changing composition of the atmosphere and land-use change.”

    My definition of a chaotic system is more unconventional. It is a dynamical system in which the components are connected with feedbacks. At any instant there will be a feedback factor connecting any two components. If a feedback factor exceeds 1 then the system becomes chaotic. If the feedback factor approaches 1 there is an abrupt change. Abrupt changes have occurred at the entry to the Bolling-Allerod inter-glacial, to the Younger Dryas stadial, and to the Holocene. Will the Anthropocene result in yet another?

  39. 139
    Piotr says:

    zebra(133): What I said is exactly correct, and you are not contradicting it… you are agreeing

    That I am not interested in wasting my time on discussing tangents that have “_nothing_ to do with what I was saying” does NOT mean that I “agree” with what you say in your tangents.

    zebra(133): “ Or are you starting a new definition debate

    I didn’t start the old one and don’t intend to start new one. Starting “ definition debates” seems like your hobby horse. Sorry, I meant: zebra.

    zebra(133): “by saying that such a system might not qualify as chaotic?”

    Again, I am not interested in your system, I was talking about “global climate” in response to the statement by Alastair(43) about … “global” climate. And I don’t need to change my definitions, I stand by them.

    zebra(133): WRT Alastair, you say “it is obvious he wasn’t talking about local climate.” But again it is a silly definitions game; “local” could mean rain at my house, or it could mean ice-free Arctic Ocean, relative to “global”“.

    That’s self-inflicted wound – it was YOU who lectured me about the need to talk about … “local climate“. Let me refresh your memory:
    Zebra(123): “ You said “local weather is chaotic but global climate is not”. But Rasmus was talking about local climate [sic!]. (As am I [sic!], here.)

    And to make painfully clear that I was referring to YOUR words about “local climate” – I did put those words in QUOTATION MARKS!
    Piotr(126): “Irrelevant, since I wasn’t talking about Rasmus. I questioned Alastair’s [words from which it was obvious] that he wasn’t talking about local climate“.

    But please, DO lecture ME how by my quoting of YOUR phrase “local climate” it is I, NOT YOU, who engages in “silly definitions game” [because] “local” could mean rain at my house, or it could mean ice-free Arctic Ocean“.

    And since in his post, Alastair(43) USED the phrase “global warming”, I seriously doubt that he meant: “rain at zebra’s house“.

  40. 140
    Piotr says:

    re zebra(133): dismissing the sense of talking about global temperature anomaly:
    zebra (133) “your little rant makes no sense. What I said is exactly correct, and you are not contradicting it… you are agreeing.

    Great argument, except:
    1. I didn’t agree with you (see my previous post);
    2. I would leave to the readers the decision on whether you are “exactly correct”
    3. Falsifiable arguments are disproven by falsifying them, NOT be you declaring that my “ little rant makes no sense

    but everything else – Great! ;-)

    To sum up: Your dismissive attitude toward talking about global surface temperature anomaly (GSTA) is based on the claim that because it “ is an effect, not a cause” it has no practical value except as a proxy for total system energy.

    Hmm, since it is the changes in that “total system energy” that DRIVE CLIMATE CHANGE – having a proxy for such an important thing seems kinda important to me, particularly if zebra didn’t offer a … better “proxy” for it. And it would important even if it WERE THE ONLY practical application. But they are NOT – I mentioned SEVERAL of them and zebra promptly falsified them by … declaring them “little rant [that] makes no sense” ;-)

    So for all those climatologists from Hadley Centre, NASA, NOAA and JMA who WASTE their time trying to calculate the GTSA, stop doing it – it has NONE of the practical values I have suggested in my “little rant [that] makes no sense“:

    Piotr(126):
    =====
    No practical value”?
    1. That’s why so much work by the major climate centres to calculate the … irrelevant historic and present-day GSTA?
    2. That’s why climatologists evaluate the strength of various CLIMATE MODELS based on their ability to recreate the … irrelevant GSTA?
    3. That’s why the most important output of IPCC are their projections of … the irrelevant GSTA?
    4. That’s why their advice to the governments on needed emission cuts is based on the evaluating different scenarioes by comparing the GSMTs they will produce?
    5. And that’s why GSTA is the most important climate metric in most geological paleoclimate studies?
    ====

  41. 141

    All,

    JDS has taken to emailing me vitriolic letters. Not sure how he got hold of my email address, though it is publicly available in some places. Apparently this is his reaction to having some of his posts boreholed. Caveat emptor.

  42. 142

    I responded to JDS’s email with a rather stiff “I did not give you permission to email me,” whereupon he promptly emailed me back saying he didn’t care and adding more abuse. I doubt very much that this guy is dangerous, but he is at least unwilling to observe social boundaries. Be on the lookout.

  43. 143
    MA Rodger says:

    GISTEMP has posted for December completing the 2020 calendar year. At +0.81ºC, December 2020 has the lowest monthly anomaly of the year which otherwise spanned +0.87ºC to +1.26ºC.
    At +0.81ºC, December 2020 is the 6th warmest December on record, sitting below the previous five years 2015 (+1.16ºC), 2019 (+1.09ºC), 2017 (+0.94ºC), 2018 (+0.92ºC), 2018 (+0.86ºC).

    The full year 2020 averages +1.022ºC and by a whisker takes top spot, just above the El Niño-boosted 2016, although close enough for folk to declare the two equal top. The top ten warmest years thus run:-

    2020 … … +1.022ºC
    2016 … … +1.018ºC
    2019 … … +0.986ºC
    2017 … … +0.926ºC
    2015 … … +0.901ºC
    2018 … … +0.853ºC
    2014 … … +0.751ºC
    2010 … … +0.725ºC
    2013 … … +0.683ºC
    2005 … … +0.682ºC

    A year-on-year graph of the GISTEMP record since 1979 is here [usually 2 clicks to ‘download your attachment’].

  44. 144
    Al Bundy says:

    “Climate chaos” or “Climate determinism” or whatever. It all seems like reporting on attendance at the Angels’ annual Top of the Pin dance because in order to make such a fine distinction one would have to have a climate that is not being shoved so forcefully towards a new paradigm. Kind of like discussing how quantum effects might alter the precise way a cannonball goes through a human torso.

    I think it was Piotr who spoke of how climate is not a direct measurement (that’s weather) but a summation that scrubs out much of the chance (chaos?) that affects individual measurements. Given that our CO2 concentration is higher today than yesterday it is essentially a given that 1/14/21’s climate is different than 1/13/21’s climate was. So where ya gonna get the summations you need in order to compare today’s climate with any other day’s with enough precision to tackle the Angel attendance question? You need years and years of data to define a climate and you have one day to do it. How about a year? Every year nowadays spikes CO2 more than a thousand sans human years.

    In other words, the whole concept of “the climate” is obsolete. Maybe we’ll have a climate again in 1000 years. Dunno. Evolution sans humans is slow, but with transplants, CRISPR, and who knows what else perhaps we’ll be able to terraform the devastation. And 1000 years gives the oceans enough time to mostly adjust to the new CO2 regime.

    Not sure what we (future generations) will do about Antarctica and especially Greenland, though. Once Greenland’s surface elevation drops a bit there’s no reasonable way to stabilize it and that could prevent a stable climate on geological timeframes, a human-induced forcing/feedback to compete with Milankovitch.

  45. 145
    Solar Jim says:

    Mike @ 131:
    Thanks for that. Somewhat perversely, it gives me some hope that other scientists, especially biologists and ecologists, are perceiving the immense challenge of even survival (of civilization) in these coming decades.

    Perhaps, beside keeping us up to date with carbonic acid gas (CO2) concentrations, you might consider an estimate of the total equivalent value, along with some related background on how estimated. After all, the planet is not responding to CO2 alone. Regards.

  46. 146
    nigelj says:

    AM @138

    “If a feedback factor exceeds 1 then the system becomes chaotic. If the feedback factor approaches 1 there is an abrupt change”

    Could you briefly explain what this means and why, or please provide a link? Im not a climate scientist so please excuse my lack of knowledge. Just curious.

  47. 147
    nigelj says:

    “Maybe we’ll have a climate again in 1000 years. Dunno. Evolution sans humans is slow, but with transplants, CRISPR, and who knows what else perhaps we’ll be able to terraform the devastation. And 1000 years gives the oceans enough time to mostly adjust to the new CO2 regime.”

    Yes it could come to that, and dont forget all that CO2 apparently sinks to the ground so we better use CRIPR to inject a few plant genes so that we can breathe pure CO2 (sarc).

  48. 148

    Interesting observation from a MSM newspaper
    “THREE consecutive years of drought, while they have stimulated the inventive resources of practical agriculturists, have had the natural effect of calling forth a plentiful crop of speculation from weather prophets and projectors, and half-instructed meteorologists, and all the philosophic tribe of Laputa in general, to whom the periodical press now affords such fatal facilities. We have often noticed that in the tabular statements of those compilers of weather records who write to the Times, useful and welcome as their communications are, every season is sure to be “extraordinary,” almost every month one of the driest or wettest, or windiest, coldest or hottest, ever known. Much observation, which ought to correct a tendency to exaggerate, seems in some minds to have rather a tendency to increase it. And many seem now to regard three dry hot years in succession as betokening some general change of climate, as if it was not perfectly certain, in the wide range of the table of what we call chances, that with our existing conditions of climate such a combination must every now and then recur. We know an ingenious theorist who would fain persuade us that a cycle of six hundred unfavorable years has just reached its termination, and that English agriculturists, who left off making wine about A.D. 1250 because their grapes ceased to ripen, will soon be making it again, and continue to do so for an equivalent number of centuries.”

    I particularly like the “every season is sure to be “extraordinary,” almost every month one of the driest or wettest, or windiest, coldest or hottest, ever known”

  49. 149
    Piotr says:

    Al, I am not sure what you wanted to say in your (144):

    – your analogy of “ discussing how quantum effects might alter the precise way a cannonball goes through a human body ” seems to be a criticism of zebra’s “ Would you not agree […] that the elements of the system will have departed from their original 30-year average to one degree or another?

    Other parts of your (144) seem to refer to me, but only “seem” – because after
    you correctly reading my argument that averaging “scrubs out much of the chance (chaos?) that affects individual” values, you proceed to

    1. asking (me?) how would one ever be able to determine that: “ 1/14/21’s climate is different than 1/13/21’s climate was

    I wouldn’t, because there is no such thing as “ 1/14/21’s climate“. Climate is on the scale of decades, NOT: DAYS.

    And since Nobody is using “climate” in the “DAILY” sense, your argument is in effect means _IF_ somebody used this word in such an absurd sense, then SUCH absurdly-defined “climate” would have been … impossible to calculate. This sounds precisely like an argument you might want to present at your “ Angels’ annual Top of the Pin dance”. I am sure it will be well received…

    2. Next you seem to imply that we can’t have climate if … things are changing: “ the whole concept of “the climate” is obsolete. Maybe we’ll have a climate again in 1000 years. .
    Climate CAN change, hence the phrase you may have heard: “ climate change”. And you can even see such “climate change” graphically – e.g. on plots of Global Surface Temperature Anomaly from 1880 to 2020, when you calculate
    moving average/local regression over period window corresponding to the climatic time-scale, see for instance the black line in
    https://ourchangingclimate.wordpress.com/2015/08/07/warm-2015-and-model-data-comparisons/
    with the justification for the time scale of smoothing, I quote:
    The black line in the graph is a so-called smooth function (Loess) over 30 years. 30 years is not an arbitrary choice, it is the number of years on which the climatic definition is based. Natural variability, e.g. caused by El Niño’s and La Niña’s or temporary dips by volcanic eruptions are averaged out on this time scale. This climatically relevant perspective of 30 years shows that there has been a steady increase in the surface temperature on Earth since the 1970s, as expected given the steady rise in greenhouse gas concentrations in the atmosphere.

    If “climate” meant no changes, then the line would be FLAT. It is NOT. Because of climate CHANGE.

    3. In the last paragraph, you changed gears again and started talking about changes over …many generations or even “geological timeframes”. This does not make the concept of climate “obsolete” nor akin of counting angels dancing on top of a pin, quite the contrary – to “generational” and “geological timescales” – climatic time-scales are both adequate and practical (see e.g. the comparison of the effects of various emission scenarioes till 2100, or graphs of temperature over geological time scales).

    To sum up, Al, I am not sure what you hoped to contribute to _this_ discussion, other than flogging that dead horse of zebra (damn those genus Equus sayings) that Killian and I already shot.

    That said, all the best at your annual dance … ;-)

  50. 150
    John Pollack says:

    nigelj@146 I agree with you that AM’s @138 definition needs some refining. His “feedback factor” is what I’d call an “amplification factor” because feedback that increases an interaction is usually called “positive” feedback. Feedback that decreases an interaction is called “negative” feedback. This means that neutral feedback with an amplification close to zero would correspond to his feedback factor near 1.

    Part of the problem that I have with his definition is that a chaotic system requires both a positive (amplified) feedback component and a negative (damped) component. If you only have damping, the system settles to a fixed, stable configuration, and no chaos. If you have only amplification, the system “blows up”, which is disruptive, but not chaotic. However, not every system with both positive and negative feedbacks is chaotic. Chaos (sensitive dependence on initial conditions) only occurs at restricted feedback values. When those values are approached from the stable realm, things get interesting.

    Another word which seems to be causing some grief is “deterministic.” Philosophers would probably be tearing their hair out at the way meteorologists tend to use the term. Meteorologists would generally agree that the real world is deterministic, even though you can’t forecast it very far. Except for radiation physics, they don’t need to bother with quantum effects, because the various macroscopic world complications quickly overwhelm the forecast before you even get to quantum complications.

    Meteorologists often refer to a the output of a single model as “deterministic.” Presumably, if you start over again with the same input and the same model, you’d get the same output. It was Lorenz’s empirical discovery that if you rounded off a couple of decimals in the input data, the results would diverge, that introduced the idea of “chaos” into meteorology. Mathematicians already knew about it in theory, but meteorologists ran across it in practice because they were doing multiple iterations in a computer before just about anyone except for bomb physicists. (I’m assuming that the bomb physicists ran across it sooner, but their results were classified.)

    An example of meteorological “non-determinism” would be taking an ensemble of forecasts using the same model, only with slightly different starting values. You can use the average to get a statistically better forecast than any individual deterministic model run. You will also get an idea of the spread of possible outcomes. As Rasmus pointed out, you can improve on that further by using different models, as well.