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Unforced Variations: May 2021

Filed under: — group @ 1 May 2021

This month’s open thread for climate science topics.

37 Responses to “Unforced Variations: May 2021”

  1. 1
    Trebor says:

    Interested in the “Net Zero means global heating will stop” I am starting to see ? What’s going on ? I thought heating would continue until equilibrium was reached.

    [Response: This is a confusion between no more emissions (net-zero) and ‘constant concentrations’. Zeke’s article at CarbonBrief is worth reading to go into this. – gavin]

  2. 2
    Killian says:

    359 Hank Roberts says:
    1 May 2021 at 3:12 PM

    > protested the application of technology to make them jobless.

    That’s a political platform I’ve heard a lot about lately, arguing that reducing industrial production of fossil fuels would put people out of work.

    Reducing the use of technology to save jobs is not the same thing as reducing the use of technology taking jobs. And what do denialists have to do with the definition of Luddite? Nada.

    I think you might be confused as to what you intend to say here.

  3. 3
    Russell says:

    Every Mayday calls for a Mayday call, for the next big thing in Existential Treat Inflation.

    This year, it has been answered by Conde’ Nast:

    https://vvattsupwiththat.blogspot.com/2021/04/the-next-big-thing-in-existential.html

  4. 4
    MA Rodger says:

    UAH has posted for April 2021 with a TLT anomaly of -0.05ºC, another monthly drop in anomaly, down from the March anomaly of -0.01ºC (Jan & Feb seeing a +0.12ºC & +0.20ºC anomaly respectively.) That makes April 2021 the =228th highest anomaly on record (out of 509 on-record months in total) and the lowest monthly anomaly since August 2014. It is also the =20th warmest April (out of 43) on the UAH TLT record and the coldest April since 2013.
    The first four months of 2021 on the UAH TLT record sits as the 12th warmest start to a year on UAH TLT, it being the coldest start since 2015.

    That of course is according to Woy Spencer’s trend-defying UAH TLT.
    RSS TLT which measures a similar bit of atmosphere does show a somewhat different story Jan-Mar to the trend-defying wobbles of UAH TLT which in turn is a lot different to the surface records Jan-Mar. So woolly hat manufacturers shouldn’t be taking this UAH posting as reason for buying a bumper stock of wool.

  5. 5
    Russell says:

    I see that Lawrance Krauss has joined Gavin on the warpath against Steve Koonin’s new book.
    https://quillette.com/2021/05/01/why-climate-science-is-like-the-rest-of-science/

    Might it be time for an actual debate on Steves Red Team revival meeting ? I’m afraid that if Steve remains unconfronted on the talking head circuit, he could turn into Cal Tech’s answer to Dick Lindzen, and sustain the brain-poaching temperature of the skeptical fever swamps for years to come.

  6. 6
    Mike says:

    Watching a coral reef die as climate change devastates one of the most pristine tropical island areas on Earth
    https://theconversation.com/watching-a-coral-reef-die-as-climate-change-devastates-one-of-the-most-pristine-tropical-island-areas-on-earth-159792

    Could we reduce short term global warming damage and losses like this one if we worked hard at controlling methane emissions? I know a lot of folks prioritize CO2 emission reductions because the long term damage is so much higher from present day CO2 emissions, but I wonder about that approach when I read an article like this one.

    I also hear the argument that addressing methane emissions will take away from our energy and ability to reduce CO2 emissions. Is that a realistic worry? Why can’t we do both?

    Cheers
    Mike

  7. 7
    Killian says:

    Re #5:

    Koonin is proof intelligence does not equal analytical skill.

    Of course, as with any climate denier, his income sources should be investigated to determine if his abject failure is his alone or bought-and-paid-for.

  8. 8
    MA Rodger says:

    With the first months of 2021 global temperature data stacking up, these 2021 SAT & TLT anomalies are obviously suggesting a cool 2021 is in the offing.
    The UK Met Office prediction for 2021 put the 2021 annual SAT anomaly somewhere between +0.91ºC & +1.15ºC which is quite a wide range. (In the Met Office table, 2014 was down at +0.92ºC while 2016 was up at +1.16ºC.) So with a few months of 2021 data to look at, it might be worth a bit of thought into the question “How cool is 2021 looking?” with a look also at the ENSO numbers and where they might be sending the SAT/TLT for 2021.

    MEI and SOI for 2020 are both looking roughly equivalent to the 2007 figures. Ignoring the the continuation of the 2007 La Niña into 2008 (which could still be mirrored in the 2021 ENSO conditions although the current ENSO predictions are for perhaps a more neutral conditions), relative to the preceding three years, 2008 saw annual SAT dip by -0.12ºC (HadCRUT & GISS),-0.10ºC (NOAA) & -0.07ºC (BEST), with the ERA5 SAT re-analysis dip -0.15ºC. As would be expected, the TLT dips were larger (-0.21ºC for RSS & -0.26ºC for UAH).
    This ENSO data would then suggest the 2021 annual SAT ending up being roughly equal to 2015, so =4th warmest year on record (ahead of 2017 & 2018).

    The Jan-Mar SAT data (Note BEST & HadCRUT are behind in their reporting.) suggest 2021 is running cooler than 2015 in ERA5, and indeed a little closer to 2014 in GISS and NOAA (so perhaps 7th warmest year on record), while RSS & UAH TLT are running a smidgen warmer than 2015 (suggesting also 7th-warmest as the wobbly TLT records would thus put 2021 below El Niño years 1998 & 2010).

  9. 9
    Mal Adapted says:

    Russell:

    https://quillette.com/2021/05/01/why-climate-science-is-like-the-rest-of-science/

    Thanks Russell, that’s a good piece. In last month’s UV, Thomas Fuller said :

    The climate consensus holds all the levers of power.

    Krauss sees it differently:

    That brings me to another colleague, Steve Koonin, a distinguished nuclear theorist from Caltech who, since 2014, when he published his first editorial on the subject in the Wall Street Journal, has continued to argue along the lines of his column’s title, “Climate Science is not Settled.” Most recently he has written a new book, Unsettled, which has already generated a buzz due in part to a long Wall Street Journal column about his views, and last week reached #3 on Amazon in advance of publication.

    Koonin’s voice carries significant clout. He was undersecretary of Energy in the Obama Administration, provost at Caltech, and also chief scientist at BP.

    AFAICT the Wall Street Journal, Amazon pre-orders and Cabinet departments all signify levers of power in the US. As a climate-science consensus supporter (i.e. “advocate”, if you insist) since 1988, I for one am guardedly optimistic the balance in my country is at last tipping toward decarbonization, due to a convergence of trends. Still, it remains to be seen just how much clout Koonin’s voice of lukewarmism yet carries with 74 million Trumpists.

  10. 10
    MarcusR says:

    Are there and newer papers describing RF from CO2, CH4 and N2O than Myhre et al., 2016 ?
    https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GL071930

    [Response: Not really. – gavin]

  11. 11
    KEVIN L DAVIS says:

    It seems to me that you guys don’t really have a clue about what’s really going on with climate change. You guys are just guessing at it. With all your studies and research no one can say for sure one way or the other. Quit acting like you guys have the answers. Bottom line you guys just don’t know you are only guessing because no one understands this. And no one in are lifetimes will be able to either, we do not have the knowledge needed to figure this stuff out yet. Maybe in another couple hundred years we will.
    Thank you

  12. 12
    KEVIN L DAVIS says:

    I’m sure you guys are very smart, just be smart enough to look past your careers and give the people the truth. There is enough bad information out there we don’t need anymore.

  13. 13
    Mike says:

    https://www.theguardian.com/environment/2021/may/04/vital-soil-organisms-being-harmed-by-pesticides-study-shows?utm_term=b987b60787728da55b7d48c0f71639e1&utm_campaign=GuardianTodayUS&utm_source=esp&utm_medium=Email&CMP=GTUS_email

    “Pesticides are causing widespread damage to the tiny creatures that keep soils healthy and underpin all life on land, according to the first comprehensive review of the issue.

    The researchers found the measured impacts of farm chemicals on earthworms, beetles, springtails and other organisms were overwhelmingly negative. Other scientists said the findings were alarming, given the importance of these “unsung heroes”.

    The analysis warned that soil organisms are rarely considered when assessing the environmental impact of pesticides. The US, for example, only tests chemicals on honey bees, which may never come into contact with soil, an approach described as “crazy”.”

    We have some work to do on changing our habits and the way we live if we want to inhabit a healthy and diverse planet.

  14. 14
    Killian says:

    11 KEVIN L DAVIS is engaging in crimes against humanity and crimes against nature.

    Why is this allowed?

    Climate denial has increased the risk of catastrophic global change. Should international criminal law be used against those who promote this dangerous trend? Economic and political leaders can no longer pretend it is business as usual. Whether they actively induce environmental harm or just ignore the existential threat against the survival of the human species, states and corporations must be held accountable for their actions or inaction regarding climate change.

    Catriona McKinnon

    https://en.unesco.org/courier/2019-3/climate-crimes-must-be-brought-justice

    “Given what we know and have known for decades about climate change, to deny the science, deceive the public, and willfully obstruct any serious response to the climate catastrophe is to allow entire countries and cultures to disappear. It is to rob people, starting with the poorest and most vulnerable on the planet, of their land, their homes, their livelihoods, even their lives – and their children’s lives, and their children’s children’s lives. For profit. And for political power.

    There’s a word for this: these are crimes. They are crimes against the earth, and they are crimes against humanity.” – Wen Stephenson

    https://earthbound.report/2019/05/21/is-climate-change-denial-a-crime-against-humanity/

    I said this long before either and still do. You want to shut down climate denial? Don’t engage it. Prosecute it.

  15. 15
    Killian says:

    6
    Mike says:
    3 May 2021 at 1:52 AM

    Watching a coral reef die as climate change devastates one of the most pristine tropical island areas on Earth
    https://theconversation.com/watching-a-coral-reef-die-as-climate-change-devastates-one-of-the-most-pristine-tropical-island-areas-on-earth-159792

    Could we reduce short term global warming damage and losses like this one if we worked hard at controlling methane emissions? I know a lot of folks prioritize CO2 emission reductions because the long term damage is so much higher from present day CO2 emissions, but I wonder about that approach when I read an article like this one.

    I also hear the argument that addressing methane emissions will take away from our energy and ability to reduce CO2 emissions. Is that a realistic worry? Why can’t we do both?

    Cheers
    Mike

    Or, we could actually solve the problem. The only option open to a society in massive overshoot is simplification. Period. This is one thing all collapse theorists I know of agree on.

  16. 16
    nigelj says:

    KEVIN L DAVIS @11 says without evidence that climate scientists dont know and are just guessing. What a classic argument from incredulity fallacy:

    https://en.wikipedia.org/wiki/Argument_from_incredulity

  17. 17
    Killian says:

    13 Mike says:
    4 May 2021 at 9:44 AM

    “Pesticides are causing widespread damage to the tiny creatures that keep soils healthy and underpin all life on land, according to the first comprehensive review of the issue.

    The researchers found the measured impacts of farm chemicals on earthworms, beetles, springtails and other organisms were overwhelmingly negative. Other scientists said the findings were alarming, given the importance of these “unsung heroes”.

    The analysis warned that soil organisms are rarely considered when assessing the environmental impact of pesticides. The US, for example, only tests chemicals on honey bees, which may never come into contact with soil, an approach described as “crazy”.”

    Yet another “Who woulda thunk it?!” moment from academia.

    I mean, no shit, great and glorious Oz?

    /sarc

    We have some work to do on changing our habits and the way we live if we want to inhabit a healthy and diverse planet.

    I was looking for some photos I used to have of a 2sq m box frame placed in a prairie vs. the same frame placed in a cornfield and the difference in biota. As above, so below. If there is nothing alive above, there will be nothing alive below and vice-versa.

    When I tell you all there is one, and only one, choice it comes from analysis across disciplines. Here the key point is soil biology and soil-building: It takes time to heal soils, particularly those loaded with pesticides because many of them are very long-lived. Building soils, i.e. improving soils not chemically saturated, can be done relatively quickly. Any place on Earth can have much-improved soils within five years and great soil within ten (while adding anywhere from 4 to 10% carbon). But chemically castrated soils need special attention to get the chems out using various techniques, including use of accumulators that are removed from the site. However, that limits significantly the rate at which C is added while it is necessary to remove the poisoned carbon (plants) used to sequester the chemicals.

    We don’t have time for anything but simplification.

  18. 18
    Astringent says:

    Kevin @11. Thankyou for highlighting the uncertainties. Clearly we need to both redouble are investment and energy in climate change research and understanding as we really can’t wait an “another couple hundred years” . And of course in the interim we really must take a precautionary principle and cut back on GHG emissions aggressively, because after all if “no one can say for sure one way or the other” things might turn out a lot worse than we thought. Thanks for your kind support.

  19. 19

    KLD: It seems to me that you guys don’t really have a clue about what’s really going on with climate change.

    BPL: Astronomers don’t really have a clue what’s going on with stars and planets, either. And geologists don’t really a clue what’s going on with earthquakes and volcanoes.

  20. 20
    Robert Ingersol says:

    Hoping someone can explain this for me. My understanding of the anomaly basis change as recently done on the UAH data, is that it would only shift the scale up, and wouldn’t affect the relative values. But looking at the before and after tables from Spencer’s site, it seems like the change in monthly 2020 values ranged from -0.12 to -0.17.

    Month Old New Diff
    2020 01 0.56 0.42 -0.14
    2020 02 0.75 0.59 -0.16
    2020 03 0.47 0.35 -0.12
    2020 04 0.38 0.26 -0.12
    2020 05 0.54 0.42 -0.12
    2020 06 0.43 0.30 -0.13
    2020 07 0.44 0.31 -0.13
    2020 08 0.43 0.30 -0.13
    2020 09 0.57 0.40 -0.17
    2020 10 0.54 0.38 -0.16
    2020 11 0.53 0.40 -0.13
    2020 12 0.27 0.15 -0.12

    What don’t I understand?

    https://www.drroyspencer.com/2021/05/uah-global-temperature-update-for-april-2021-0-05-deg-c/

    https://www.drroyspencer.com/2021/01/uah-global-temperature-update-for-december-2020-0-27-deg-c/

    [Response: If there is a new monthly climatology calculated with different baseline, there may be some adjustments by month. The deltas in that case would have an annual cycle. This would happen if the (as is the case) warming is seasonally dependent. – gavin]

  21. 21

    #19, BPL–

    You forgot “Computer scientists don’t really have a clue with what is going on with computers!” I mean, where’s the data from before 1950!

    But why do I bother? Clearly no-one will read this, because it would be a miracle if such shaky ‘science’ actually led to these comments being posted.

  22. 22
    MA Rodger says:

    Robert Ingersol @20,
    Perhaps a simpler explanation is that with a period of warming the different months of the year do not warm at a uniform rate. Therefore the adjustment will not be uniform for all months when anomalies a calculated using a new anomaly base.
    When you calculate the average anomaly for the anomaly reference period (what UAH call “New Reference for annual cycle 1991-2020”), the anomaly will be roughly zero. So in the table of TLT data provided by UAH, March 1991-2020 averages +0.001ºC, a small rounding error. And for September the average is -0.0003ºC.
    But if you calculate these averages for what was the old reference period 1981-2010 the averages are respectively -0.127ºC and -0.168ºC and (ignoring further incorporated rounding errors) this yields the changes of -0.12 & -0.17 shown by you @20 for March & September.

  23. 23
    MA Rodger says:

    A first view of surface temperature for April 2021 is posted by the Copernicus ERA5 re-analysis. The April 2021 global anomaly is given as +0.1905ºC, a tiddly-tad up on the March anomaly of +0.1895ºC. April 2021 becomes the 80th highest anomaly in ERA5 (in the trend-defying UAH TLT it was 228th).

    April 2021 sits as the 7th warmest April on the ERA5 record (20th in UAH), the top-10-Aprils running:-
    1st… 2016 … … … +0.53ºC
    2nd… 2020 … … … +0.52ºC
    3rd… 2019 … … … +0.44ºC
    4th… 2017 … … … +0.33ºC
    5th… 2018 … … … +0.31ºC
    6th… 2010 … … … +0.25ºC
    7th… 2021 … … … +0.19ºC
    8th… 2007 … … … +0.17ºC
    9th… 1998 … … … +0.12ºC
    10th.. 2014 … … … +0.11ºC

    The start of 2021 Jan-Apr averages +0.17ºC and sits as the =7th warmest start-of-the-year equaling 2015, a year which now sits 6th warmest for complete calendar years, close behind the last 5 years 2016-20.
    A year-on-year graphic of ERA5 monthly anomalies is (hopefully**) here. **Google sites is changing its functionality & I have yet to master its scope & limitations.

  24. 24
    Mr. Know It All says:

    14 – Killian
    “…..is engaging in crimes against humanity and crimes against nature.”

    Doubt it’s against the law in the USA – we still allow a modicum of “free exchange of ideas” here. Do you have a safe place to go when you read a comment that you don’t like? If not, here’s a website you may like – all comments are WOKE:

    https://bikeportland.org/2021/05/06/has-our-comment-section-improved-i-think-so-330847

    ;)

    We’re running cool here in the great Pacific Northwest USA. Tied or broke a record cold night a few weeks back – makes me wonder how that is possible with so much CO2 in the atmosphere during this “climate emergency”. Maybe there’s something wrong with the theory? New theories appear from time to time. Could warming be related to the electric earth?

    https://www.youtube.com/watch?v=hW4kCP-ascw

  25. 25
    Alastair McDonald says:

    Kevin,

    Re #11 where you wrote:
    “It seems to me that you guys don’t really have a clue about what’s really going on with climate change. You guys are just guessing at it. With all your studies and research no one can say for sure one way or the other.”

    You are quite right. 20 years ago they were predicting that X2 CO2 would lead to +3K warming +/- 50%. Now they are still saying X2 CO2 will lead to +3K but with a range of -50% and + 100%. That certainly seems to me like “no one can say for sure one way or the other.”

    However, you also wrote: “Bottom line, you guys just don’t know. You are only guessing because no one understands this. And no one in our lifetimes will be able to either. We do not have the knowledge needed to figure this stuff out yet. Maybe in another couple hundred years we will.”

    It has only taken me a couple of decades to figure it out, but no doubt it will take a little longer to persuade others I am correct.

    CO2 does not drive the climate by altering the outgoing long wave radiation. Much of the radiation the Earth emits is absorbed in the surface atmospheric boundary layer, where it is saturated. Thus applying the Bouguer-Lambert-Beer absorption law, doubling the concentration will half the distance to the saturation height meaning the boundary layer will absorb twice the heat. This doubles the downwelling radiation from CO2 to the surface. In the tropics the CO2 greenhouse effect causes water vapour to be evaporated ad dominate the greenhouse effect, but the effect of H2O is limited because the water vapour condenses to form clouds which cut off the solar energy which heats the surface.

    However, in polar regions, including the third pole, where the cold ensures there is little water vapour, CO2 is the main greenhouse gas and this accounts for the polar amplification of global warming due to CO2.

    The snow line is set by CO2 concentration. An increase in CO2 leads to snow and ice melting and a reduced albedo effect. This is the main cause of the global warming we are experiencing. In other words global warming is not caused by less outgoing long-wave radiation but rather by less outgoing short-wave (reflected) radiation.

    Re #1,

    Trebor and Gavin,

    The consequence of this is that when we stop pumping CO2 into the atmosphere temperatures and sea level will continue to rise because of the higher (but not increasing) CO2 levels. And this is true whether my model is correct or not.

  26. 26

    #24, KIA–

    C’mon, KIA, you’re not that dense; you know perfectly well about variability. Stop trolling.

    “Could warming be related to the electric earth?”

    No, it couldn’t.

  27. 27

    Electric earth: “Abstract theories for cause and effect aren’t needed when the patterns of Nature are laid bare for us to see.”

    OMG.

    That stuff is seriously bat shit.

  28. 28
    Robert Ingersol says:

    Gavin and MAR, thanks for the full explanation. I guess I would have figured it out if I had thought hard enough, but really appreciate your help.

  29. 29
    William B Jackson says:

    #24 Weather is weather, climate is climate….trends are trends. When will you understand the difference?

  30. 30
    Jim Eager says:

    It seems to me that Kevin Davis doesn’t really have the intellectual tools to know whether or not “you guys” have a clue about what’s really going on with climate change, much less to know what “the truth” is or is not. But hey, this is the era when one person’s ignorance is just as valid as another person’s education and acquired knowledge, right?

  31. 31
    Susan Anderson says:

    KIA24 has reached one of his or her regular lows in ignorant dishonesty. I know Killian is a little over earnest and can be annoying with it, but at least he understands our planetary emergency and is trying to address it rather than spread a dressing of phony skepticism over an increasingly obvious reality.

    Isn’t there a place called the crank shaft for things like that? [it might be a good idea to delete this too if KIA’s awfulness is put where it belongs]

  32. 32
    Killian says:

    24 Mr. Know It All says:
    7 May 2021 at 2:41 AM

    14 – Killian
    “…..is engaging in crimes against humanity and crimes against nature.”

    Doubt it’s against the law in the USA – we still allow a modicum of “free exchange of ideas” here.

    A criminal speaks. Too many of you are foolish enough to let them and amplify them. Here are two points worth clarifying.

    1. Crimes Against Humanity are not federal crimes, they are international crimes tried in the International Court of Justice or some such, just like war crimes.

    2. Ecocide is already an official crime in some places and will become an international crime, IMO. Regardless, whether a court or gov’t has stated it to be a crime or not does not matter: It’s a crime whether prosecuted or not, or do you think murder is only murder if they catch the murderer?

    3. The First Amendment does not cover lying, particularly for personal gain.

    You are a criminal. Sadly, this site and those who engage you on any of your climate lies are enablers for your lies. Big Lies only have power when the naive assist in their incessant repetition.

    Your posts here are crimes against humanity and against nature. You should be arrested, tried, convicted and imprisoned.

    I used to get banned from sites for saying this. But now? Look:

    https://www.nbcnews.com/news/world/ecocide-movement-pushes-new-international-crime-environmental-destruction-n1263142

    The only useful response anyone should ever have to you WRT your climate lies is that you are a criminal who should be banned from social media and prosecuted. You and whomever (almost certainly) pays you to do this.

  33. 33

    KIA 24: We’re running cool here in the great Pacific Northwest USA. Tied or broke a record cold night a few weeks back – makes me wonder how that is possible with so much CO2 in the atmosphere during this “climate emergency”. Maybe there’s something wrong with the theory?

    BPL: Maybe you don’t understand the difference between weather and climate, even after having had it explained to you a thousand times? Maybe you’re trolling? That seems much more likely.

  34. 34

    Meanwhile, in the Arctic

    Arctic sea ice extent averaged for April 2021 was 13.84 million square kilometers (5.34 million square miles). This was 410,000 square kilometers (158,000 square miles) above the record low for the month set in 2019 and 850,000 square kilometers (328,000 square miles) below the 1981 to 2010 average. The average extent for the month ranks sixth lowest in the passive microwave satellite record.

    So, lowish but not presently record-lowish.

  35. 35
    Mal Adapted says:

    Mr. Ironically Anosognosic Typist:

    Tied or broke a record cold night a few weeks back – makes me wonder how that is possible with so much CO2 in the atmosphere during this “climate emergency”. Maybe there’s something wrong with the theory?

    LOL! One can hardly ask for a more succinct expression of pseudoskepticism. IAT never imagines that maybe the theory is sound, and there’s something wrong with his understanding 8^D!

  36. 36
    Alastair McDonald says:

    Gavin,

    The blog post by Zeke that you recommended in Comment #1 ends:’

    ‘Finally, while current best estimates suggest that temperatures will stabilise in a zero-emissions world, that does not mean that all climate impacts would cease to worsen.

    Melting glaciers and ice sheets and rising sea levels all occur slowly and lag behind surface temperature warming. A zero-emissions world would still result in rising sea levels for many centuries to come, with some estimates suggesting that at least 80cm of additional sea level rise is “locked in”.’

    This is very similar to how I concluded my #25 comment.

    Zeke continues:

    “To stop these impacts may, ultimately, require reducing global temperatures through net-negative global emissions, not just stopping temperature from rising by reaching net-zero.”

    Do you agree?

    Moreover, Zeke and [MacDougall, A. H., Frölicher, T. L., Jones, C. D., Rogelj, J., Matthews, H. D., Zickfeld, K., Arora, V. K., Barrett, N. J., Brovkin, V., Burger, F. A., Eby, M., Eliseev, A. V., Hajima, T., Holden, P. B., Jeltsch-Thömmes, A., Koven, C., Mengis, N., Menviel, L., Michou, M., Mokhov, I. I., Oka, A., Schwinger, J., Séférian, R., Shaffer, G., Sokolov, A., Tachiiri, K., Tjiputra, J., Wiltshire, A. and Ziehn, T. (2020) ‘Is there warming in the pipeline? A multi-model analysis of the Zero Emissions Commitment from CO2’, Biogeosciences, vol. 17, no. 11, pp. 2987–3016]
    appear to be ignoring the ice-albedo effect, which being a positive feedback will not just continue – it will accelerate, and so global temperature will not only continue to rise after zero emissions, it will rise at an accelerating rate!

    I can only assume that Dr C.E.P. Brooks’ book, Climate Through the Ages is no longer read, since he showed that a rise of 2 degrees Celsius in the Arctic would lead to a complete loss of the sea ice there. This appears to be what is happening now. So maintaining temperatures at their current levels will not prevent the eventual loss of that ice, which as a result of the positive feedback will be abrupt. That abrupt rise in temperature will scupper any possibility of holding the global temperature rise below 1.5 or even 2.0 degrees Celsius.

  37. 37
    Guest(O.) says:

    Some weeks ago I mentioned Interval Arithmetics as – maybe – a good way to enhance climate science computations (by reducing the need for extraordinary computational power, and therefore reduce power consumption of climate science computations).

    But now I think this kind of arithmetics does only help in very few situations, and is extremely bad for other kinds of computation and even much worse than classical floating point operations. Interval arithmetics can lead to extremely big computational errors.

    But I have found a stanford talk on a different kind of arithmetics, based on projectional spaces, which seems to be a very good enhancement of numerical computation.
    I think this looks promising.

    See here:

    Stanford Seminar: Beyond Floating Point: Next Generation Computer Arithmetic

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