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You are here: Home / Climate Science / Unforced Variations: Jun 2021

Unforced Variations: Jun 2021

2 Jun 2021 by group

This month’s open thread for climate science. Start of the meteorological summer, official hurricane season (outlook), the final stretches of the IPCC AR6 review process and a rare conjunction of Father’s Day and the summer solstice. Please stay on topic.

Filed Under: Climate Science, Open thread

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199 Responses to "Unforced Variations: Jun 2021"

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  1. MA Rodger says

    1 Jun 2021 at 8:36 AM

    An interesting use of the GRACE/GRACE-FO data to calculate global land evapotranspiration published in Pascolini-Campbell, M. et al. (2021) ‘A 10 per cent increase in global land evapotranspiration from 2003 to 2019’ [ABSTRACT] with associated CarbonBrief article HERE.

  2. MA Rodger says

    1 Jun 2021 at 1:05 PM

    UAH TLT has been posted for May with an anomaly of +0.08ºC, a rise on March & April’s anomalies (-0.01ºC & -0.05ºC respectively) but still below Jan & Feb anomalies (+0.12ºC & +0.20ºC respectively). That gives May 2021 the =111th highest anomaly on the UAH TLT record (out of 510 on-record months. It is the =10th warmest April (out of 43) on the UAH TLT record. (April 2018 sits in 12th warmest spot.)

    The first four months of 2021 on the UAH TLT record average +0.07ºC and sit as the 14th warmest start to a year on UAH TLT, it being the coldest start since 2014.

  3. John Mashey says

    2 Jun 2021 at 1:49 AM

    Every now and then a bad paper slips through into otherwise OK journal. Here’s a thread on recent one:
    https://twitter.com/JohnMashey/status/1399890397883551746

    If you recall the 2014 https://en.wikipedia.org/wiki/Pattern_Recognition_in_Physics” trainwreck, there’s a connection.

  4. MA Rodger says

    2 Jun 2021 at 6:32 AM

    John Mashey @3,
    The offending paper is available in all its blunderful glory HERE although it is being reviewed by the publishers, so don’t hang around – it may be disappeared.

    I note within the paper’s Abstract the phrase “If not refuted…” which perhaps the author thought was something that may happen in the future and not something which has already happened many many times in the past.

  5. Russell says

    2 Jun 2021 at 12:27 PM

    This summer may be the first to see half the world’s population living in cities, and experiencing at first hand the amplification of global warming by urban heat island effects.

    The multi-billion ton carbon footprint of keeping billions of city dwellers cool militates for expanded efforts to mitigate the magnitude and human impact of this problem

    https://vvattsupwiththat.blogspot.com/2021/05/climate-communication-time-to-lighten-up.html

  6. Mike says

    2 Jun 2021 at 4:44 PM

    Jun. 1, 2021 = 417.04 ppm

    Jun. 1, 2020 = 418.32 ppm

    upside down day!

    Ok, that’s good news. Show me an upside down week. I haven’t noticed one of those to day.

    Here’s where we are this past week:

    Last Week

    May 23 – 29, 2021 418.92 ppm
    May 23 – 29, 2020 417.83 ppm
    May 23 – 29, 2011 395.13 ppm

    Cheers

    Mike

  7. b fagan says

    2 Jun 2021 at 8:49 PM

    John Mashey #3 – thanks for that link to what was certainly a “very interesting and provocative” paper. Dr. Curry can sure pick ’em.

    As the author Himself noted somewhere in his piece: “In contrast to climate simulations, the present analysis is open to falsifiability since its fallacy, if any, could be pointed out without ambiguity.”

    And how. He kind of left out hundreds of millions of years of climate data, plus physics and everything else – except he included vague misunderstanding of the models.

    It was so pedantic, yet so completely wrong, lacking in evidence, unconvincing… Maybe it was because I watched Blazing Saddles this past weekend, but the imagery that came up while reading him lecture on and on was like if someone unfamiliar with ranching lectured a roomful of cattle breeders about the clear mistakes in their methods, while he begins to show them the way a smart guy like him would do artificial insemination – but he’s not yet noticed the animal he picked, about to be startled by his gloved arm, is a bull.

    He’s not going to change any minds, but the attempt is at least going to liven up the day for the cattle breeders.

  8. nigelj says

    2 Jun 2021 at 9:05 PM

    “Nutritional quality of crops in a high CO2 world: an agenda for research and technology development. Kristie L Ebi10,1, C Leigh Anderson2, et al.”

    https://iopscience.iop.org/article/10.1088/1748-9326/abfcfa

  9. Western Hiker says

    2 Jun 2021 at 10:38 PM

    MA Rodger, #2

    You know that Spencer and Christy shifted the goalposts, right? But in the comment section,
    “+0.08C for May on the new 1991-2020 baseline is equivalent to +0.20C on the old 1981-2010 baseline.”

  10. Carbomontanus says

    3 Jun 2021 at 1:16 AM

    Dr.R.Climate

    Since it is unforced variations with mentioning of meteorological summer, I can mention for you that this year it is back to normal here where I live at the Oslofjord. As I wrote: Prunus padus blossom is the most reliable signal for peasants and gardeners, for when to guarantee frost- free nights until next autumn. This year it came late enough, and “May chill makes the peasant barns full”. This year 2021 it seems back to 1960-70 normal according to old signals.

    Syringa vulgaris blossom end of may. That tree, if really wild and vulgar and able to seed out for itself, is a solidly termophil indicator in contrast to the solidly Heliotrop trees, that shoot and blossom regardless chill or warmth, who obviously orientate rather by the length of daylight..

    Then this year 2021 we have late- and quite enormeous blossom of Malous x-domesticus, the wild apple seedlings. Also back to normal rather end of may beginning of june.

    I compare this to the ices in the Barents sea, that are aloso a bit “late” this year.

    OK, thus if you compare Termophile with Heliotrop trees, then you have a very proper climate- indicator along with the Köppen system.

    Those signals and rules are also traditional.

  11. Mike says

    3 Jun 2021 at 4:20 PM

    Climate tipping points could topple like dominoes, warn scientists
    https://www.theguardian.com/environment/2021/jun/03/climate-tipping-points-could-topple-like-dominoes-warn-scientists

    Domino toppling tipping points. That sounds like a bad outcome.

    Cheers

    Mike

  12. Piotr says

    3 Jun 2021 at 6:29 PM

    John Mashey (3) Every now and then a bad paper slips through into otherwise OK journal. Here’s a thread on recent one

    See also Gavin twitter – https://twitter.com/ClimateOfGavin/status/1398079441973264388

    contains an update on the publisher response to the questions about the choice of peer-reviewers. I wonder if for instance – Richard Lindzen was the paper’s or the author’s suggestion… ;-)

    But I think we owe thanks to Judith Curry – without her enthusiastic recommendation – the paper may have went unnoticed and and therefore unchallenged… ;-)

    If “The road to hell is paved with good intentions …” would this make Judith go straight to … heaven?

  13. Piotr says

    3 Jun 2021 at 6:51 PM

    A good public lecture by Gavin at CMOS symposium -https://cmos.ca/site/congress/publiclecture
    Organizers said they would record it, so it might be available at some point. And in intro they mentioned Realclimate … ;-)
    Asked my question I posted before o UV – whether we may be lulled into a false sense of security – if we see different models predictions converge – but if all of them are missing some important feedback or tipping point – they may agree well with themselves (=high precision) but ot with “reality” (=poor accuracy”).
    Gavin said that for now the models do not converge – and he doesn’t think all of them are missing an important feedback/tipping point.

    My other question was chosen – on how best to present to public/politicians low-likelihood but high impact risks.

    I guess the insurance industry must have it done routinely to determine the baseline for their rates = the Sigma (sum) of (p_i*I_i)
    where p_i probability of event or scenario i, I_i – damage/cost if it happens) ?

  14. sidd says

    4 Jun 2021 at 12:49 AM

    Re: if you compare Termophile with Heliotrop trees, then you have a very proper climate-indicator

    Thanks. I have noticed the same.

    sidd

  15. MA Rodger says

    4 Jun 2021 at 8:52 AM

    Having spotted the CRU announcement that HadCRUT5 now supersedes HadCRUT4 (“New versions were published in December 2020: HadCRUT5, CRUTEM5 and HadSST4. These are the recommended versions.”), it occurred to me that those gallant idiots at the GWPF use this data for their masthead illustration, something they have had to defend in the past due to their masthead’s stretched-out trend-flattening dimensions. So have the Gentlemen Who Prefer Fantasy adopted HadCRUT5 with its inconvenient 40% extra warming trend 2001-20?
    Apparently not.
    The tell to look for is the 2014-16 annual temperatures which, unlike HadCRUT4, are almost straight in HadCRUT5 (as shown in this Clive Best graphic).

    …

    And while visiting the Gentlemen Who Prefer Fantasy, I also noticed a hot-off-the-press-&-still-steaming pile of nonsense by the crazyman Ole Humlum entitled ‘State of the Climate 2020’, Humlum being one of their brave Academic Advisory Council which now for some reason has members which are departed this world (and presumably provide ‘advice’ through seances).
    It seems that Humlum has been scrawling out annual “State of the Climate” reports since 2016. The general idea appears to be an excuse to pump out stuff suggestive of AGW being a non-problem. So we read gems like:-

    “Since 1979, lower troposphere temperatures have increased over both land and oceans, but most clearly over land areas. The most straightforward explanation for this phenomenon is that much of the warming is caused by solar insolation, but there may well be several supplementary reasons, such as changes in cloud cover and land use.”

    or:-

    “Global sea levels are monitored by satellite altimetry and by direct measurements from tide gauges along coasts. While the satellite record suggests a global sea-level rise of about 3.3mm per year, data from tide gauges along coasts all over the world suggest a stable, average sea-level rise of 1–2mm per year. The measurements do not indicate any recent acceleration (or deceleration) in sea-level rise. The marked difference between the two data sets still has no universally accepted explanation, but it is known that satellite observations face complications in coastal areas. However, for local coastal planning, it is the tide-gauge data that is relevant, as detailed later in this report.”

    As such nonsense suggests, the task of writing out an Annual ‘State of the Climate’ report is well beyond crazyman Ole Humlum. I note that even on an obviously factual basis he demonstrates his incompetence. Since the first of these annual reports Humlum has been producing some interestingly wrong graphics/comment presenting TLT temperature records.

    Back in 2015 UAH was replacing TLTv5.6 with TLTv6.0 and similarly in 2017 RSS replaced TLTv3.3 with TLTv4.0. Since the second of Humlum’s steaming piles (the 2017 version) a graphic has shown RSS TLTv4.0 and “a large adjustment towards higher temperatures from 2002 onwards; about +0.1ºC” relative to RSS TLTv3.3. The 2020 graph Fig3b is fine as it shows correctly an adjustment greater than +0.2ºC. And the difference between “about +0.1ºC” and “greater than +0.2ºC” is large enough to make Humlum’s statement wrong – something the man appears to be well-practiced at achieving.

    Of course, the UAH TLT didn’t suffer such a profound adjustment as RSS TLT. Humlum attempts to show this in Fig3a. (In terms of the warming trend 1979-2015, the RSS adjustment saw a 40% increase from +0.113ºC/decade to +0.0193ºC.decade while UAH numbers show a 20% decrease from +0.140ºC/decade to +0.110ºC/decade.)
    But there is something very strange with Humlim’s Fig3a. The UAH adjustments Humlum describes saying “only a few small adjustments have been made to the UAH series.” But they are so small to be entirely invisible on the Fig1a 37-month rolling average trace outside the period 2010-11. Humlim’s 37-month rolling-average trace shows the maximum deviation between v5.6 & v6.0 to be just -0.03ºC when they actually exceed that deviation for most of the period 1979-2015, the maximum deviation actually being -0.12ºC.

    So I’m left wondering if this grand work by GWPF is an attack on AGW science. Or is actually an attack on the English language? There is the phrase “You couldn’t make it up”. It seems the GWPF are attempting to undermine the usefulness of this phrase by demonstrating that “you can make it up!!!”

  16. Mike says

    4 Jun 2021 at 10:02 AM

    Guardian article about a new netflix/Attenborough offering.

    “One of Australia’s leading coral reef scientists is seen breaking down in tears at the decline of the Great Barrier Reef during a new Sir David Attenborough documentary to be released globally on Friday evening.”

    https://www.theguardian.com/environment/2021/jun/04/david-attenborough-netflix-documentary-australian-scientists-break-down-in-tears-over-climate-crisis?utm_term=0f11625e7fa451d03cc0a35f9ba0f486&utm_campaign=GuardianTodayUS&utm_source=esp&utm_medium=Email&CMP=GTUS_email

    I think Attenborough is trying to make up for his reluctance to cover the human disaster aspect of the natural world. Attenborough also carries some controversial baggage with regard to his ideas on population that tend to overlook how important the consumption component for various human populations is for calculating the true impact of population.

    https://nakedpolitics.co.uk/2020/10/19/why-david-attenboroughs-new-documentary-perpetuates-racism-and-eco-fascism/

    Lots of opinions available on that stuff.

    Here’s some data that looks like fact:

    Daily CO2

    Jun. 3, 2021 = 420.12 ppm
    Jun. 3, 2020 = 417.61 ppm

    April CO2

    April 2021 = 419.05 ppm
    April 2020 = 416.45 ppm

    CO2.earth

    Background rate of CO2 increase hanging in at something around 2.5 ppm per year in my estimation.

    We should do something about that CO2 increase, but of course discussion of those efforts should take place elsewhere. This is the UV thread.

    Cheers

    Mike

  17. Mike says

    4 Jun 2021 at 10:20 AM

    Mixed news at best:

    “Sea ice across much of the Arctic is thinning twice as fast as previously thought, researchers have found.

    Arctic ice is melting as the climate crisis drives up temperatures, resulting in a vicious circle in which more dark water is exposed to the sun’s heat, leading to even more heating of the planet.

    The faster ice loss means the shorter north-eastern shipping passage from China to Europe will become easier to navigate, but it also means new oil and gas extraction is more feasible.”

    https://www.theguardian.com/world/2021/jun/04/arctic-sea-ice-thinning-twice-as-fast-as-thought-study-finds?utm_campaign=Carbon%20Brief%20Daily%20Briefing&utm_content=20210604&utm_medium=email&utm_source=Revue%20Daily

    file under “faster than expected.”

    Cheers

    Mike

  18. Mal Adapted says

    4 Jun 2021 at 1:14 PM

    MA Rodger:

    John Mashey @3,
    The offending paper is available in all its blunderful glory HERE although it is being reviewed by the publishers, so don’t hang around – it may be disappeared.

    I note within the paper’s Abstract the phrase “If not refuted…” which perhaps the author thought was something that may happen in the future and not something which has already happened many many times in the past.

    Also from the paper’s Abstract:

    As simply based on fundamental logic and on the concepts of cause and effect, an epistemological examination of the geochemical analyses performed on the Vostok ice cores invalidates the marked greenhouse effect on past climate usually assigned to CO2 and CH4.

    Ah, good ol’ “fundamental logic” and “cause and effect”. At the outset this sounds like any DK-afflicted AGW denier’s argument from personal incredulity. I only skimmed the full paper, but felt the author’s defensive arrogance dripped from the screen. Expressing confidence in his superior “epistemological” skills, one Pascal Richet contradicts the robust consensus of his trained, disciplined scientific peers, claiming AFAICT that because astronomical cycles are causes of climate change, changes in atmospheric greenhouse gas concentrations can only be effects.

    His empirical errors aside, the author appears not to acknowledge that science is necessarily a collective enterprise: Even with superior training in empirical methods he’s still the easiest person to fool, leaving him utterly dependent on his peers to catch him at it. As a comprehensive non-expert myself, I defer (albeit always tentatively and provisionally) to the collective wisdom of actual experts, who have long since refuted Richet’s claim. Abundant citations are linked on this very page, and I won’t presume to recapitulate their conclusions yet again.

  19. John Mashey says

    4 Jun 2021 at 4:26 PM

    PIotr(12): I happened to notice via Curry Tweet, but others were alert to it, and posted, links included at the end of that thread I did.

  20. Jim Hunt says

    4 Jun 2021 at 5:29 PM

    A new paper about Arctic sea ice thickness from the UK’s Center for Polar Observation and Modelling has just been published. It makes disturbing reading from where I’m sat:

    https://GreatWhiteCon.info/2021/05/month-in-review-arctic-science-edition/#Mallett

    An extract from the concluding summary:

    We found that interannual variability in average sea ice thickness of the marginal seas was increased by more than 50 % by accounting for variability in the snow cover. On a seasonal timescale we find that variability in the snow cover makes an increasing contribution to the total variability of inferred sea ice thickness, increasing from around 20 % in October to more than 70 % in April.

    We also observed that the trends in SnowModel-LG data propagated through to the sea ice thickness time series, amplifying the decline in regions where it was already significant and introducing significant decline where it did not previously exist. This occurred in spite of the compensating effect of enhanced interannual variability.

  21. Killian says

    4 Jun 2021 at 9:38 PM

    More accurate snow measurements on ASI equals ASI thinning, you guessed it, faster than expected. I hope this helps PIOMAS and others to improve their models for ice thickness. I stopped paying much attention to ice thickness because the modeling was so obviously out of sync with what we could see happening. But, that thickness, thus volume, is vital to understanding just how much ice is actually in the Arctic basin.

    Scientists, any thoughts?

    When the sea ice thickness in the period 2002–2018 is calculated using new snow data with more realistic variability and trends, we find mean sea ice thickness in four of the seven marginal seas to be declining between 60 %–100 % faster than when calculated with the conventional climatology.

    https://tc.copernicus.org/articles/15/2429/2021/

  22. Killian says

    5 Jun 2021 at 12:03 AM

    An explainer Twitter thread from Robbie Mallett on the new snow cover/ice thickness paper:

    https://twitter.com/RobbieMallett/status/1400730516744253443?s=20

    Important point 2: The inter-satellite-mission (Envi/CS2) bias is big. So the absolute value of the trends is subject to high uncertainty.

    However the acceleration of trends where they exist (and introduction of new trends) is a robust feature of accounting for declining snow.

  23. Killian says

    5 Jun 2021 at 12:33 AM

    11 Mike says:
    3 Jun 2021 at 4:20 PM

    Climate tipping points could topple like dominoes, warn scientists

    Domino toppling tipping points. That sounds like a bad outcome.

    Surely this is not a surprise to you, Chris?

    “We provide a risk analysis, not a prediction, but our findings still raise concern,” said Prof Ricarda Winkelmann

    Risk analysis. Huh. Imagine that, a risk framing for climate… Who’da thunk it…?

    at the Potsdam Institute for Climate Impact Research (PIK) in Germany. “[Our findings] might mean we have less time to reduce greenhouse gas emissions and still prevent tipping processes.”

    What?! Faster than predicted? You mean, like, “Time is short?” No, we have, like, tons of time for incremental changes. Everybody says so… NetZero by ’50, right? But, errr… how short?

    The level of CO2 in the atmosphere required to push temperatures beyond the thresholds could be reached… “In the next years or decades…

    …the risk clearly is increasing…

    Oh… that short. Shocked, I tell you. Never saw it coming!

    In May, scientists reported that a significant part of the Greenland ice sheet was on the brink of a tipping point. A 2019 analysis… may already have crossed a series of climate tipping points… “an existential threat to civilisation”.

    Alarmist! Or… maybe not…?

    The climate crisis may also mean much of the Amazon is close to a tipping point, at which carbon-storing forest is replaced by savannah…

    An example of the complex chain of interactions the researchers tracked is the melting of the Greenland ice sheet. …fresh water into the ocean and slows down the AMOC… less heat is transported from the tropics towards the north pole, which in turn leads to warmer waters in the Southern Ocean. …destabilise ice sheets in Antarctica, which pushes up global sea level and causes more melting at the edges of the Greenland ice sheet.

    This is what worries me about the way this is written up: Was this a surprise to them? I mean, this wasn’t *obvious* already? Or, is this paper merely a result of wanting to quantify in writing what has been obvious for a while?

    I have been harping on tipping points and cascades for *ever* and getting no traction. Seriously, this stuff is *obvious.* Or should be. I have specifically talked about cascading failures and more recently trophic cascades precisely because this is how systems function and because it was obvious our general abuse of the planet had reduced hysteresis.

    It’s really scary to think this wasn’t already obvious to them…

    And don’t get me wrong, more information is always good, and finding specific teleconnections is very useful to understand cause and effect in changes we observe, but we passed the knowledge tipping – knowing enough to respond intelligently and effectively a long time ago.

  24. Killian says

    5 Jun 2021 at 1:16 AM

    Meant to include this from the cascading tipping points article:

    “The study suggests that below 2C of global warming – ie in the Paris agreement target range – there could still be a significant risk of triggering cascading climate tipping points…

  25. BSRK Aditya says

    5 Jun 2021 at 2:40 AM

    Hello everyone,

    There is:

    1. What’s implied by rising CO2
    2. CO2 Sinks
    3. Sinks for what’s implied by rising CO2

  26. mike says

    5 Jun 2021 at 8:04 PM

    at K at 23: Yes, I agree with you that much of what is being reported on the tipping points has been easy to see for quite a few years now. You and I agree that it should have been obvious to scientists and they should have been speaking out about it.

    I think the price for speaking out is pretty high. I think there is a lot of fairly conservative groupthink going on in many academic circles these days. I don’t mean conservative, like, hey they are voting for republicans, but conservative as in taking few or no risks with public statements that might subject them to the kind of vendetta that the redstaters and climate deniers like to launch against scientists who speak too clearly about our situation.

    It is possible to feel pretty sad watching this play out, but it’s not clear to me that feeling sad accomplishes much, so I am working on connecting things within a very large and long time frame for the planet that recognizes that the planet and its ecosystem have rebounded numerous times from extinction events.

    I do hope that the current extinction event proceeds very slowly because I really love my grandkids.

    Cheers

    Mike

  27. William Jackson says

    5 Jun 2021 at 9:47 PM

    Am I alone in finding #25 unintelligible?

  28. MA Rodger says

    6 Jun 2021 at 4:02 AM

    mike @16,
    Your “data that looks like fact” is factual in that the numbers are those reported by ESRL’s MLO CO2 ‘Trends in Atmospheric Carbon Dioxide’ page. What is questionable is whether they are useful “facts”.
    With May 2021 average yet to be posted, you report the April 2021 & April 2020 averages which yield a 12-month rise of 2.6ppm. The average May 2021 MLO CO2 from ESRL will (this calculated from their daily numbers) be something like 419.1ppm and with May 2020 reported at 417.31ppm that would suggest a 12-month rise of roughly 1.8ppm.
    Given the ENSO conditions of recent months, a low rise in CO2 should be expected, perhaps lower than this ~1.8ppm for May. And we may yet see ‘lower’ as, despite the large wobbles in MLO’s CO2 over the last months, the rate has been generally dropping and continues to fall.
    Mind, estimating even a “hanging in at something around” version of a “background rate of CO2 increase” without some indication of the reason for such an estimate is a long way from providing “data that looks like fact”.

  29. Brian Dodge says

    6 Jun 2021 at 9:53 AM

    “Since 1̶9̶7̶9̶ earlier today,̶ ̶l̶o̶w̶e̶r̶ ̶t̶r̶o̶p̶o̶s̶p̶h̶e̶r̶e̶ ̶t̶e̶m̶p̶e̶r̶a̶t̶u̶r̶e̶s̶ stovetop temperatures have increased over both l̶a̶n̶d̶ ̶a̶n̶d̶ ̶o̶c̶e̶a̶n̶s̶ burners and surfaces, but most clearly over ll̶a̶n̶d̶ ̶a̶r̶e̶a̶s̶ burners. The most straightforward explanation for this phenomenon is that much of the warming is caused by s̶o̶l̶a̶r̶ ̶i̶n̶s̶o̶l̶a̶t̶i̶o̶n̶ electricity, but there may well be several supplementary reasons, such as changes in i̶n̶ ̶c̶l̶o̶u̶d̶ ̶c̶o̶v̶e̶r̶ ̶a̶n̶d̶ ̶l̶a̶n̶d̶ ̶u̶s̶e̶ control settings.”

  30. Kevin McKinney says

    6 Jun 2021 at 12:37 PM

    #27, WJ–

    Am I alone in finding #25 unintelligible?

    No, not at all.

  31. Killian says

    6 Jun 2021 at 10:51 PM

    28 MA Rodger says:
    6 Jun 2021 at 4:02 AM

    mike @16,
    What is questionable is whether they are useful “facts”.

    The average May 2021 MLO CO2 from ESRL will (this calculated from their daily numbers) be something like 419.1ppm and with May 2020 reported at 417.31ppm that would suggest a 12-month rise of roughly 1.8ppm.

    Something you may have missed, gents, but we had something happen that is, so far as I know, unprecedented (one of you numbers people might want to confirm that as it may be a large, important climate shift): Mauna Loa CO2 peaked in… April.

    I was all “What the hell?!” until I thought for a few seconds: Spring is coming faster and faster, so the drawdown of C into plant matter will come sooner. Voila!

    This is affecting the May numbers.

    Another weird thing, though, is despite the really early peak (it’s usually mid-/late May), the drop-off after peak has been significantly slower than usual. The peak, overall, is really flattened; more Kilimanjaro than Fuji.

    Given the ENSO conditions of recent months, a low rise in CO2 should be expected, perhaps lower than this ~1.8ppm for May.

    The La Nina has ended, but the effects of large amounts of energy moving – or not moving – aren’t all immediate, of course. This year should have a lower rise than usual bc of LN.

    Glad for the LN, but the next EN might be… really bad. And at least one after that almost certainly will be a monster due to solar activity increasing.

    despite the large wobbles in MLO’s CO2 over the last months

    Wobbles? What wobbles? Oh, you mean those excursions noticed a couple years ago in Feb, then Jan… that were “skyrockety” overreactions?

    ;-)

  32. Killian says

    6 Jun 2021 at 11:07 PM

    26 mike says:
    5 Jun 2021 at 8:04 PM

    at K at 23: Yes, I agree with you that much of what is being reported on the tipping points has been easy to see for quite a few years now. You and I agree that it should have been obvious to scientists and they should have been speaking out about it.

    I think it has been obvious to climate scientists, but what drives their thinking are “most likely” pathways. Their normal mode is to dismiss outliers. I suspect it becomes more central to their thinking than perhaps they realize. Scientific reticence is real in more ways than one.

    I think the price for speaking out is pretty high.

    Sure, but price of not doing so has ended up being so much higher. But is acknowledging long-tail risk really “speaking out?” Those risks are real, not fake news. I do not fault them for their reticence, per se, but for the lack of balance. It’s easy enough to say, “Yes, everything could go sidewise even faster than our worst-case scenarios, BUT the likelihood is tiny, so we need to focus on the 1 and 2 sigma stuff, maybe some 3 sigma, unless or until we get stronger signals on extreme risks.”

    Or, at the least, not be so hard on those that have been willing to, both scientists and laypersons. Gavin, in particular, has been downright rude to fellow scientists.

    I think there is a lot of fairly conservative groupthink going on in many academic circles these days. I don’t mean conservative, like, hey they are voting for republicans, but conservative as in taking few or no risks with public statements that might subject them to the kind of vendetta that the redstaters and climate deniers like to launch against scientists who speak too clearly about our situation.

    Let the nuts run the nuthouse, you get bad outcomes.

    It is possible to feel pretty sad watching this play out, but it’s not clear to me that feeling sad accomplishes much, so I am working on connecting things within a very large and long time frame for the planet that recognizes that the planet and its ecosystem have rebounded numerous times from extinction events.

    I almost never feel sad or down, maybe a few days out of any given year, because I know how fast it’s coming, but also know it’s very, very fixable – except for SLR! Meters of that coming no matter what we do. BUT, we can, I will say for the umpteenth time, be back to 260ppm in my remaining lifetime if we so choose – just not the way every else thinks.

    I do hope that the current extinction event proceeds very slowly because I really love my grandkids.

    With regenerative simplification, yes. Without it, no.

    Full stop.

    P.S. No idea why I called you Chris above! Sorry.

  33. nigelj says

    7 Jun 2021 at 2:41 AM

    Mike @26, the reason scientists haven’t discussed tipping points publicly much until recently (the last 4 years) might also be because theres been no real consensus until recently. Refer the link below and notice the range of opinion on arctic permafrost back in 2013 from scientists thinking it was stable, to others thinking things could destabilise quickly to opinions in between. If scientists had spoken out then it would have utterly confused the public. Its good there is now more discussion on tipping points.

    https://www.scientificamerican.com/article/how-the-ipcc-underestimated-climate-change/

  34. MA Rodger says

    7 Jun 2021 at 4:41 AM

    The Copernicus ERA5 re-analysis has been posted for May with a global SAT anomaly of +0.26ºC, the highest anomaly of 2021 so-far. Previous 2021 monthly anomalies have sat in the range +0.06ºC to +0.24ºC.

    May 2021 is the 5th warmest May on the ERA5 record (behind 2020, 2016, 2017 & 2019) and May 2021 is the 58th highest anomaly in the all-month EAR5 record.

    The first five months of 2021 average +0.19ºC and are the 7th warmest start-to-the-year on the ERA5 record behind 2016, 2020, 2017, 2019, 2018 & 2010.

  35. MA Rodger says

    7 Jun 2021 at 1:37 PM

    Killian @31,
    You suggest “Mauna Loa CO2 peaked in… April“ and that this shows “Spring is coming faster and faster.”

    How do you reckon that? The MLO monthly data from ESRL actually shows in 2021 it was the May average CO2 that was a tiny bit peakier than April while looking back through the record, the April monthly average has been peakier in the past. It was peakier than May in 1970, 1976, 1999 and 2000. So on that count there is no support for “Spring is coming faster and faster.”

    Of course you may be thinking daily peaks for each year, although would that amount to showing “Spring is coming faster and faster”?
    ESRL does show two-years-worth of daily data on its Interactive Plots page. And that is showing both April 3 & April 8 as the highest daily readings (above 421ppm) for 2021 (so far) although in UV threads earlier this year we have discussed the increase in the incidence of rogue CO2 readings which may be somehow a factor. While in 2020 the peakiest CO2 day shown was in June, so perhaps it was a very sloooow Spring just last year.
    But in the absence of ESRL data for earlier years, the Scripps Keeling curve does provide daily data back to 1958. Scripps don’t always provide a daily reading as willingly as ESRL so they have no data given for 3/4/21 or 8/4/21 but still manage to give the peakiest daily reading for 2021-so-far as 30 April, so not May. And if we look back though earlier years (back to 1972) we find peakiest days for 1972 25 April, 1979 28 April, 1981 17 April, 1983 29 April, 1989 29 April, 1997 30 April, 1999 10 April, 2000 14 April, 2001 11 April, 2007 16 April, 2012 12 April, 2015 13 April, 2016 8 April, 2021 30 April. So again, on that count there is no support for “Spring is coming faster and faster.”

    You end your comment attempting to lay credit for the unusual wobbles in this years MLO data I mentioned @28. Do examine the MLO record since the start of March – six bold peaks and five skulking troughs. Such wobbles are actually not so unusual, other than their regularity. So it is nothing to do with skyrocketry or “excursions noticed a couple years ago.”

  36. Carbomontanus says

    7 Jun 2021 at 3:22 PM

    Ladies and Gentlemen

    You are discussing tipping points and domino- effects.

    Those phaenomenæ have their premises, thus rather easy to discuss.

    Think first in terms of liting a fire. There we have the necessary auto- katalytic effect. When it burns, it get hot, and when it gets hot, it burns.

    The CAVSA EFFICIENS goes both ways, or the process causes itself.

    Then think in terms of MINIMA NATVRALIS. Meaning that a thing must be large enough in order to exist or to “work” at all. And you often have to use a lot of matches and try again and again and again until it “catches” fire and burns on by itself.

    That is a tipping point.

    Also if you have a cesium- cell and variable input light frequency. The cell “starts” to conduct at a very definite, minimal frequency.

    That “Minima naturalis” is an atomic or molecular or macro- molecular, quantum- mechanical phaenomenon in most cases.

    Or the mixture of H2 + Cl2. It is stable in darkness at normal temperature, but it detonates if exposed to sunlight. That is another chain- reaction. It combines into HCl giving off 2 very agressive free radicals H. and Cl. that brings the reaction furter, and you will have a quite dramatic domino- effect, an avalache.

    One can discuss the U235 fission reactor or bomb the same way.

    And an important example: 2H2 +O2 -> H2O. That fameous reaction is efficiently moderated or “squelsced” if the gas mixture also contains rather small ammounts of H2O- gas. It then says “Poff” instead of “BANG!” Nuclear reactors are actually “moderated” in a similar way; the H2O molecules adsorb and stop a lot of the very agressive free radicals that can carry on the avalanche.

    OK, we have a lot of practical examples for discussing avalanches, tipping ponts, domino- effects , chain reactions, wild- fires, and Covid 19.

    So all we need to know further is to know practical geophysics and climate well enough, and look up for possible, practical examples that can be studied and discussed, foreseen, eventually falsified, or avoided.

  37. Killian says

    8 Jun 2021 at 1:19 AM

    35 MA Rodger says:
    7 Jun 2021 at 1:37 PM

    Killian @31,
    You suggest “Mauna Loa CO2 peaked in… April“ and that this shows “Spring is coming faster and faster.”

    How do you reckon that? …would that amount to showing “Spring is coming faster and faster”?

    You left out some stuff. Try again.

  38. nigelj says

    8 Jun 2021 at 3:58 AM

    This new study seems very significant: “Cooling effect of clouds ‘underestimated’ by climate models, says new study”

    https://www.carbonbrief.org/cooling-effect-of-clouds-underestimated-by-climate-models-says-new-study?utm_campaign=Carbon%20Brief%20Weekly%20Briefing&utm_content=20210604&utm_medium=email&utm_source=Revue%20Weekly

    It appears to suggest climate sensitivity is in the middle of the range, ‘if’ its correct: Although personally I think we should assume climate sensitivity might be high, so mitigate,mitigate, mitigate. The worst we do is end up with wind turbines and coal left in the ground. This is surely better than risking some huge climate shift.

  39. Mike says

    8 Jun 2021 at 12:18 PM

    nigel at 38 says: “It appears to suggest climate sensitivity is in the middle of the range”

    Can you cut and paste the text from that article that suggests climate sensitivity is in the middle of the range, please?

    I read the piece and I did get a sense that the cloud and rain stuff is a bit of good news, but I didn’t think the article suggested that climate sensitivity is in the middle of the ECS range, only that ECS is likely to be lower than previously calculated due to the cloud and rain issue that is being resolved.

    Maybe I missed something in the article? Or maybe what you mean to say is that “you think the article suggests that climate sensitivity is in the middle of the range?”

    Cheers

    Mike

  40. nigelj says

    8 Jun 2021 at 5:21 PM

    Mike @39
    “Can you cut and paste the text from that article that suggests climate sensitivity is in the middle of the range, please?

    The article says: “The high climate sensitivity of CMIP6 models attracted widespread attention within the scientific community, as a higher climate sensitivity means that future warming will be more rapid and intense than previously thought…” So that given the latest study we are discussing essentially says climate sensitivity is significantly lower than this ( as you mentioned) I just paraphrased it as medium climate sensitivity to summarise what the article implied to me. People talk about a range of low, medium, and high sensitivity. There’s nothing in the study to suggest climate sensitivity would be low. Not sure what you are worried about. I said the article “appears” to suggest medium climate sensitivity, not that it literally said that.

  41. John Mashey says

    8 Jun 2021 at 6:22 PM

    On that dodgy paper in journal HGSS, looks like Copernicus has acted quickly. The abstract is still there, but disclaimer says paper itself is blocked.
    The discliamer links to a several-page discussion of the review process, which includes following. Recall that the author Richet is also a topic editor of the journal and the editor in this case was Gregori, so: Richet suggested 4 referees including Gregori (1 wrote), Gregori suggested 4 more (3 wrote), and the 4 who wrote included Lindzen and longtime petroleum guy Hovland.

    .Copernicus wrote:
     The editor nominated 8 referees, of which 6 agreed to write and 4
    eventually submitted a report.
     Out of 8 nominated referees:
    o 4 were suggested by the author upon submission.
    o 6 have a limited or no publication record in climate sciences, ice
    core geochemistry, or atmospheric sciences.
    o 6 are publicly known as being in favour of or having ties to an
    industry benefiting from the manuscript’s conclusion.

     Out of the 4 referees that submitted a report:
    o 1 was suggested by the author upon submission.
    o 3 have a limited or no publication record in climate sciences, ice
    core geochemistry, or atmospheric sciences.
    o all are publicly known as being in favour of or having ties to an
    industry benefiting from the manuscript’s conclusion.
    o all agreed within 1-2 days and submitted their reports within 1-8
    days (1 x same day, 2 x 4 days, and 1 x 8 days).
    o 3 suggested technical corrections and 1 suggested major revision.

     The handling topical editor was also on the list of referees suggested by
    the author.

  42. Mr. Know It All says

    8 Jun 2021 at 7:50 PM

    34 – MA Rodger
    “The first five months of 2021 average +0.19ºC and are the 7th warmest start-to-the-year on the ERA5 record behind 2016, 2020, 2017, 2019, 2018 & 2010.”

    That does not correlate with CO2 warming theory. There is a lot more CO2 in the atmosphere today than in previous years; quite a bit more than 2010. How can it be that 2010 was warmer than today with the current CO2 concentration?

    What accounts for the failure of measured temperatures to correlate with CO2 warming theory?

  43. Mike says

    9 Jun 2021 at 10:41 AM

    at Nigel: it’s a matter of accuracy in statement and attribution that concerns me. I don’t think the cloud article said that the ECS is likely to be in the middle range. I think the article indicates that the ECS is likely to be lower than the high range of ECS that caused concern recently.

    I don’t think the article said that ECS would be “significantly” lower than the high range of ECS, nor did I.

    I feel like you may be applying a bit of spin to your re-presentation of statements of others or articles. Seems like a bad idea to me in the post truth age.

    I am not too concerned about it, I think most folks here recognize that you skew to an inherent centrist spin and I work to minimize my inherent alarmist spin/skew.

    Look at the trouble that came to David Baltimore recently when he overstated his thoughts on the origins of Covid 19: https://www.theguardian.com/world/2021/jun/09/leading-biologist-dampens-his-smoking-gun-covid-lab-leak-theory

    I think we should all be cautious to speak accurately, to speak in first person about our thoughts or to quote others accurately to avoid unnecessary misunderstandings and overstatement controversies and disagreements.

    Cheers

    Mike

  44. Omega Centauri says

    9 Jun 2021 at 11:18 AM

    Know it all @42.
    There is always short term climate variability imposed upon the slow steady rise from CO2 forcing. Just like watching the temperature rise and fall irregularly in your backyard during spring. Its why we need long datasets to
    distinguish signal from noise.

  45. William Jackson says

    9 Jun 2021 at 1:04 PM

    #42 Sadly Mr. KIA proves once again, in his haste to seem intelligent, that his name is a lie! Weather varies from year to year and month to month. The trend is warming, individual years months weeks and days will do as they do!

  46. Carbomontanus says

    9 Jun 2021 at 1:07 PM

    #42 Mr. Know it all:

    “What accounts for the failure of measured temperatures to corelate with CO2 warming theory?”

    There I have no problem at all, because I see quite much “noise” in the overall background signal, obviously due to weather, that is different from climate.

  47. Piotr says

    9 Jun 2021 at 5:17 PM

    Somebody (42) “What accounts for the failure of measured temperatures to correlate with CO2 warming theory? ?

    See an earlier entry:

    “Dear Diary,
    after talking to my QAnon friends, who expressed their admiration for my expertise in the worldwide climate scientist conspiracy, I was told, that Donald J. Trump may be passing my home at 8pm in a limousine cavalcade, on the way to the White House to be reinstated as the Greatest President Ever. I grabbed the flowers I occasionally buy so the people think I have a girlfriend or wife, and rushed outside.
    After 4 hours I returned home, dejected, put the flowers into the Papier-mâché vase I made for my grade 6 project (“Outstanding Participation ribbon!”). I fired the comp to check what the hell happened – only to be told that that this only a ruse to throw off the Forces of Evil that may be monitoring our communications on our secret platform called: “Twitter”. Uuuff, what a relief. Still, they could have called me after the 2hrs. I ended with “Be Best!”, logged off, put on my tinfoil pajama and went to bed.
    But he sleep did not come. Something was bothering me. Not, not the damn static from my pajama, I got used to it. I got up, drunk a glass of water, walked around the room trying to figure out what was off. Then in a moment of pure inspiration
    I looked at my window, looked again, Yes,got it! There was no Sun in the sky anywhere to be seen!

    I run to my comp, logged in and typed furiously, the wry smile never leaving my face: “ There is no Sun in the sky outside my window!!!! What accounts for the failure of the observed lack of the Sun to correlate with “the Sun does exist” theory????” That will show them!

    After the emotions subsided I went to bed again. Looked at the bookshelf – on it
    my Nemesis, its black title: “The Difference between Local Weather and Global Climate for Tools”, looked today …. a tad less menacing. You just wait, a few more such nights and I will REAP the bookstore plastic wrapping off you!

  48. MA Rodger says

    9 Jun 2021 at 5:54 PM

    Mr. Know Shit All @42,
    You ask “What accounts for the failure of measured temperatures to correlate with CO2 warming theory?”
    Have you ever heard of the El Niño Southern Oscillation? You of course have. If there is “failure,” I suggest you look in the mirror to identify the reason and then consider why is it you ask such dumb-ass questions?

  49. Richard Caldwell says

    9 Jun 2021 at 10:27 PM

    Mr KIA,

    Please go back to entertainment. Asking stupid questions that are based on lies, yes, lies, just doesn’t cut it. You know that there is no theory that locksteps weather with CO2 levels. Wiggles and waggles ARE part of the theory, dumbass-on-purpose, and you know it.

    For once, be honest. Tell the damn truth in your next post. Tell us the truth as you see it.

    Not gonna happen. You never tell the truth from a position of knowledge. Lies? Sure. Ignorant goop a fifth grader would rightly laugh at? Par. After all, you are a GOPper.

    But you, “sir” will NEVER tell the truth here. Never.

  50. nigelj says

    9 Jun 2021 at 10:41 PM

    Mike@43

    “I am not too concerned about it, I think most folks here recognize that you skew to an inherent centrist spin ”

    No.I don’t do that, and you don’t know what most folks think here. Just consider the full context and ask yourself if your claims really have validity: I said “It appears to suggest climate sensitivity is in the middle of the range, ‘if’ its correct: Although personally I think we should assume climate sensitivity might be high, so mitigate, mitigate, mitigate. The worst we do is end up with wind turbines and coal left in the ground. This is surely better than risking some huge climate shift.” So given this full statement, how can you possibly say I’m spinning something to appear centrist? You cant. You are reading things into things that just aren’t there.

    I just paraphrased very briefly what I thought the article meant. We generally talk about low, middle and high climate sensitivity, yes? So I said the study appears to suggest middle climate sensitivity. To conclude this means I’m centrist is silly.

    What I really want to know is what the experts think of the study (or yourself). Here it is again:

    https://www.carbonbrief.org/cooling-effect-of-clouds-underestimated-by-climate-models-says-new-study?utm_campaign=Carbon%20Brief%20Weekly%20Briefing&utm_content=20210604&utm_medium=email&utm_source=Revue%20Weekly

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