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libertador at 02:43 AM on 25 March 2019Holistic Management can reverse Climate Change
For the full picture it would be necessary to include opportunity costs if comparing feedlot to AMP like in Stanley et al (2018). The AMP system needed 120% more land than feetlot. This additional land could have been used to sequester carbon in other ways, if not used for AMP. This would lower the amount of sequestration relative to feedlot.
I have not calculated this yet. Some estimates for such opportunity costs have been given in Searchinger et al (2018).
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Tom Dayton at 01:22 AM on 25 March 2019There's no empirical evidence
JoeZ, here is a detailed factual debunking of Moore’s claims.
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JoeZ at 00:50 AM on 25 March 2019There's no empirical evidence
I've read much of this thread. I'm sitting on the fence because I can see and appreciate ideas from both sides. Here's my question: what percentage of climate change is due to human causes, and that being mostly carbon emissions? Of course the climate is changing and of course CO2 is greenhouse gas. But I haven't yet seen any convincing argument that it's almost entirely due to carbon emissions. My skepticism of GW due primarely from human causes comes from the work of Dr. Patrck Michaels: https://www.cato.org/people/patrick-michaels. He may be wrong but he's certainly not a "flake". His YouTube video at: https://www.youtube.com/watch?v=fA5sGtj7QKQ is very convincing- yet I'm not convinced- only keeping my mind open to all ideas. As to why I'm expecially interested in this subject- I may get into at some other time. I sense that few people have more qualifications to discuss the subject than Dr. Michaels.
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Eclectic at 21:24 PM on 24 March 2019Climate's changed before
TVC15 , if you have past experience in debunking creationists, then you may well have come across the [science journalist] you-tuber Potholer54 who has done many videos on the same subject area.
Maybe you are not aware that Potholer54 has done 40+ videos on climate science denialism. Most of them are around 10 minutes long; some more like 15 minutes. But I heartily recommend them. He is meticulous in shooting down the denialists' claims & in demonstrating their falsehoods. He gives his references ~ and he is careful to base his comments on the evidence as determined by peer-reviewed papers in reputable scientific journals (in other words, he does does not act as a talking head spouting his own opinions . . . unlike most you-tubers).
You will find Potholer54 very useful, because he is skilfully attacking many of the prominent "public denialists", and his videos will cover many of the points that you will wish to use in debating denialists. He doesn't cover everything ~ but you will find him a very easygoing method of gaining climate scientific knowledge, both directly and indirectly.
Yet there's more ~ his videos are done in a humorous style (which I find very entertaining).
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MA Rodger at 20:05 PM on 24 March 2019Climate's changed before
Correction to #656,
The ECS=3ºC of course includes feedbacks. Without them the CO2 forcing would be 1ºC per doubling. So it reduces to 1-in-30.
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MA Rodger at 20:02 PM on 24 March 2019Climate's changed before
TVC15 @652,
The usual response I would give to the various accusations using 'Global Warming has been converted into Climate Change because of <some cover-up>' is to point to the name of the UN IPCC which was formed in 1988. So any genuine reason for converting from the term Global Warming to Climate Change would have to pre-date 1988. Most do not.
The 4% of CO2 attributable to anthropogenic sources has in the past been an account of gross annual emissions which annually were back-in-the-day 6Gt(C) anthro, 60Gt(C) ocean, 100Gt(C) biosphere. Of course, the net emissions yield a 100% anthro as the oceans & biosphere absrob as well as emit (& as they absorb 55% of the anthro emissions, you could say the anthro percentage is 220%).
The pre-industrial CO2 levels wer 280ppm and they are now 409ppm. So an actual percentage of of today's atmospheric CO2 would be 46% anthro.
The relative contribution of CO2 to Earth's greenhouse effect (New Scientist has a page on it as probably does SkS if we were to look) is somewhere between 26% (the effect with only CO2) and 15% (the drop in the effect if CO2 were removed). Call it 20% and with water vapour 50%.
But the 1-in-1,500,000 quoted by the denialist troll is the anthro contribution from CO2 relative to water vapour. If the GHE is 33ºC and half is water vapour, while anthro CO2 forcing is roughly 2Wm^-2, with ECS=3ºC for 3.7Wm^-2. So CO2(anthro) equates to (3 x 2 / 3.7)/(33/2)=0.098 or 1-in-10.
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TVC15 at 19:43 PM on 24 March 2019Climate's changed before
Hi Electric!
I am a bit perplexed as to how I responded to you in the wrong thread??? My apologies to the mods.Thank you for the feedback! It's much appreciated.
I've cornered this denier in the past with respect to his flagrant ignorance sounding where the carbon in our bodies originated. He ran far away. I find it amusing he's back as if he's forgotten. LOL
I did a search on the author of that open resource paper I linked in the wrong thread and came up with a few hits. Thus why I wanted to hear what others thought about the credibility of that paper.
Thank you so much for your responses. I often debunk the denialists with the information I find on this site. I love this site and am spreading the knowledge I gain from it as well as from the comment section.
I am muchb more skilled at debunking the creationists, however human caused climate change denialists are just as amusing. :)
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Eclectic at 18:38 PM on 24 March 2019Climate's changed before
TVC15 ,
you have replied to me on the wrong thread. Perhaps a moderator could move your post into slot #654 in this thread.
TVC15 , you should be amused when your denier says he is an MD and Engineer. There are quite a few denialists who claim to be (and possibly are) engineers ~ some of the worst crackpot climate ideas come from ostensible engineers. ( I myself know a post-doctorate researcher in a biological field, who is a member-in-good-standing of his local Flat Earth Society. In the end, it is only the real physical evidence which counts. )
To misquote Alexander Pope : "A little learning is a dangerous thing . . . and many engineers know just enough science to be dangerous."
If his "MD" you mention is some sort of Medical doctorate, then we are getting into deeper waters ~ and Medical researchers should know better than to apply the confounding-factor-laden biomedical field to the hard-science field of climatology.
Simply, I don't think it's worth pursuing the instrumentation question. He's trying to distract you down into a rabbit hole. Myself, I'd point out to him (and the readers) that thousands of highly-expert scientists have spent decades assessing/ analysing/ cross-checking the various instrumentation aspects of temperatures. If your denier friend has some definite evidence of gross error . . . then he should frankly point it out, and also publish his findings to the whole world, so that the enormous pyramid of mainstream science comes tumbling down. But so far, there has been no sign of that happening !
As for the "methodological note" you mention, it is to be found in a rather low-ranking journal, and (judging by the Extract**) it contains a considerable amount of taurine excrement [ usually abbreviated to: BS ]. Actually, I did skim through the body of the "note", and it wasn't nearly as bad as I had expected ~ but it was mostly to do with causation/correlation in a general way and really had little relevance to climate science. However, the Extract itself mentioned "Popperian" and was largely an attack on the IPCC & mainstream science . . . and I suspect its raison d'etre was simply to be read by & cited by denialists [who wouldn't ever read the body of the note, and wouldn't care a jot for understanding Popper].
** The warning sign here is "Popperian". With apologies for my mixed metaphor ~ but when Popper or Popperian occurs in a paragraph about climate, then your ears should prick up, and you become hyper-suspicious that you are being handed a plateful of BS.
Popper's philosophy has its virtuous aspects within certain limited circumstances, but little of that is relevant to climate science. "Popper" and "Popperian" are often these days quoted by denialists who have little real interest in (or knowledge of) the philosophy of science ~ all that these denialists want is a trendy-sounding cudgel to knock real scientists on the head with . . . however inappropriate it may be. They just want "the optics of it" (if I may use a modern ugly phrase).
All too easy (for the half-alert reader of Popper) to fall into a semantic jungle, instead of keeping focus on the physical realities of this universe.
TVC15 , don't let the denialist lead the dance. Aim for his weak points (which he has tried to conceal).
Another apology ~ this time for my own long waffle: but there are some gems scattered through it !
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TVC15 at 14:08 PM on 24 March 2019There once was a polar bear – science vs the blogosphere
Hi Electric @ 653,
Yes both deniers that I posted about are both male. This latest denier boasts that he's an MD and Engineer. LOL he displays a low level of emotional intelligence and the comments about the source of carbon in our bodies and how great CO2 is for the earth thus we need more of it, shows his lack of basic science understanding.
I'm not certain how to debate anything he posted other his misinformed comments about CO2.
I don’t know exactly what instruments are used in the graph that I posted, where can I find this information? I don’t know what is the relative accuracy and standard deviation of each temperature measurement method? How would I find this information?
At first I thought it was cherry picking but it is important to know what quality checks are in place for any of the instruments or analyzers used to measure climate temperatures. I've been asked by 2 separate deniers to name the instrument used to measure climate temperatures. I would like to be able to provide an answer but I don't have access to climate lab instrument maintenance and quality assurance data.
I found this open source paper and perhaps this is where he is getting his ideas from. Is this a credible source?
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Trevor_S at 13:38 PM on 24 March 20192019 SkS Weekly Climate Change & Global Warming News Roundup #12
says the world is about to see a major shift towards climate action
That seems naively optimistic. NSW just re-elected the LNP. The only party who takes climate change seriously The Greens, didn't get a look in.
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Eclectic at 11:34 AM on 24 March 2019Climate's changed before
TVC15 @652 ,
I am sure you are not really stunned by his* intellectual incompetence ~ but he has enough intelligence to display (via Motivated Reasoning) a barrage of Gish Gallop and rhetorical waffle.
*almost certainly he is a male ~ since women usually have more sense than to lose themselves in the quagmire of climate denialism. Prof. Curry excepted: she does a fine job of vagueness and "could-possibly-be" and unjustified sophistry and "confusionism" smoke&mirrors. In person, I have only ever met one woman who was an extreme denialist ~ she was an elderly geologist (retired). A few other women seemed to be of the "Yes Dear" type, just going along with their husband's delusions. ;-)
TVC15 , in replying to the "intelligent idiot" you mentioned, you have two reasons for engaging with him. One is to present commonsense factual science to the observers/readers [of course he himself is impervious to reason] . . . and the second reason is that you find it intellectually stimulating and fun.
Plck out and attack one or two of his weaknesses. Exposing him there, will by association throw doubt on his other points. Readers will be thinking: a falsehood in one area means he could be a liar in most areas. But always it should be fun for you (though sometimes partly a chore also).
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TVC15 at 08:59 AM on 24 March 2019Climate's changed before
Hi I'm back to seek more debunking knowledge help from you guys.
I posted the below graph to debunk a denier who was trying to claim that: Now the same frauds, sorry "experts," that were behind global warming have changed their rhetoric and branding to "climate change."
Various Measurments of Global TemperatureNext think you know a loud chest pounding denier jumps in with this wall of questions.
1. Are you even aware as to what instruments were used to measure temperature in your "graph" and what locations were used?
2. Do you know how "average" temperatures are statistically massaged?
3. Do you know how "proxy temperatures" are determined?
4. Why was there not cooling during the Depression, then warming in WW2?
5. Is it valid to compare temps measured by digital instruments, compared to mercury thermometer instruments, vs "proxy" measurements?
6. What is the relative accuracy and standard deviation of each temperature measurement method?
7. Did you know that man accounts for only 4% of all atmospheric Co2, and that total Co2 is only .04 % of atmospheric gases?
8. Did you know that the relative contribution of "man made" Co2 (that 4%), compared to water vapor , is 1/1,500,000th?
9. Did you know that ALL of the carbon atoms in your body (as you are an organic organism) was once CO2? That is the carbon cycle; CO2 is as important to life on earth as water and oxygen, yet the left has labeled it a "pollutant".My response/question to each of this deniers claims.
1. Where can I find this information?
2. Define: "statistically massaged"
3. Yes
4. Not sure how to respond due to the wording of the question.
5. Not sure if this is even worth addressing
6. Don't know
7. False - however I don't know where to find good numbers to debunk this myth.
8. Show me your sources
9. False
This denier is a chest pounding denier who will criticize the instruments, claims the numbers are "massaged", make ridiculous claims about the source of the C in our bodies.Below are his favorite statements:
It is odd indeed when the AGW crowd claims the high ground of "science", then immediately violates every basic premise of actual science:
1. A hypothesis in not "proven" until the null hypothesis is refuted.
2. real science welcomes further debate, experimentation, and examination of the hypothesis- cults do not.
3. real science does not require falsification of data and statistical analysis
4. real science is indifferent to the conclusions- cults have a very vested interest in outcomes
5. in real science, those questioning a hypothesis are welcomed, rather than silenced or labeled "deniers".
6. in real science, action is not taken to "remedy" a problem until a hypothesis is proven
7. in real science, rarely is there one single cause of natural phenomenon. In the AGW cult, the "villain" or cause of all problems is CO2.I am stunned at the minds of people like this!
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nigelj at 08:38 AM on 24 March 2019New research, March 11-17, 2019
OPOF @4, and the denialists will accuse any climate science website of being politically motivated, regardless of what it says. It's just part of their silly rhetoric.
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nigelj at 08:36 AM on 24 March 2019New research, March 11-17, 2019
OPOF @4,
I did consider that, but we won't convince the hard core denialists whatever we do, especially by appeasing them and letting them set the terms of the discussion or website content. It's only the middle ground of people we can connect with, and they probably want an answer to the question about whether government has some ulterior motive like a money grab. Provided such a refutation is evidence based and doesn't make political value judgements.
I agree with the second half of your comment.
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Kevin C at 08:35 AM on 24 March 2019Holistic Management can reverse Climate Change
A further brief update: I'm still looking into this but there were multiple unplanned demands on my time next week, and I have a conference next week.
The papers of Teague et al are central to this discussion, and following the downstream citations looks to be a productive way forward.
A recent example is Stanley et al (2018), which also finds high rates of C sequestration over 4 years. They suggest that these rates may be sustained for several more years, but also imply that the rates will not be sustained indefinately - maintainability of sequestration rates (which in turn is closely coupled with permenance of the sequestered carbon) is one of the central issues with Savory's initial claim.
The other problem is extrapolation from single or similar locations to a global scale. Abdalla et al (2017) and Sherry & Ritchie (2013) both highlight the fact that the impacts of grazing may change sign between locations based on the presence of C3 vs C4 grass species, with Abdalla also noting substantial variation between climatic zones.
Extrapolation of local results to the globe and short term results to a 40 year period are therefore problematic. This may explain why even the large sequestration potential suggested by my extrapolation of Teague is much greater than the result of Lal who actually provides global and multidecadal estimates.
Given that naive extrapolation of the work of Teague still leads to an estimate of the carbon sequestration potential 4 times lower than that claimed by Savory, it still looks as though Savory's claim is indefensible and requires a rebuttal. I think Seb and I could probably improve the tone and nuance of the rebuttal in the light of some of the newer papers on AMP/MP, but unless there are some global/long period results we have missed I don't see that the conclusions of the rebuttal on the sequestration claim are going to change very much.I'm very happy to look at more papers, but addition papers quoting the same local or short term results we have already seen don't really help. Non-naive global and/or long term sequestration projections are the most helpful information.
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One Planet Only Forever at 07:49 AM on 24 March 2019New research, March 11-17, 2019
nigelj
It may not be helpful to add a myth that "global warming is a scam to give governments more money and power". That may give the politically-motivated deniers (which is the vast majority of them) more oxygen to incorrectly accuse this site of being politically-motivated.
And the wrong type of people 'winning power' can indeed abuse global warming in scams to give 'Themselves' more money and power.
My most recently developed preference is that it would be more helpful to call people who incorrectly claim that 'information presented on this site should be strictly science based (no discussion of the climate science evaluations of the future consequences of a lack of correction of developed economic activity), 'politically motivated by an incorrect and harmful developed desire to continue to benefit as much as possible from the burning of fossil fuels (a harmful desire that can be changed/corrected by improved awareness and understanding)'.
This is not an area of research to be pursued in climate science or sites like this one that help improve awareness and understanding of climate science and the related corrections of developed human activity to develop sustainable improvements for humanity. This is an Ethical and Moral matter that leaders (in business and politics), should be responsibly improving their awarenss and understanding of (rather than creating misleading claims and promoting misunderstanding in the general population regarding climate science that participants in sites like this one have to put effort into attempting to over-come and correct).
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nigelj at 06:48 AM on 24 March 2019New research, March 11-17, 2019
Regarding comment @1 thankfully deleted. I didn't want to give it oxygen but one related comment might be appropriate. We sometimes hear the climate denialist claim that global warming is a scam to give governments more money and power. This is a myth of course, and might deserve a place in the list of myths with a suitable refutation (eg carbon fee and dividend obviously doesn't give them power and money). I had a look, but can't see it in the list.
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nigelj at 06:39 AM on 24 March 2019The temperature evolution after 2016 suggests hotter future
I was looking for something completely unrelated in the list of sceptical myths, and I came across this skepticalscience.com myth buster on Scarfettas 60 year cycle. Hiding in plain sight!
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One Planet Only Forever at 04:44 AM on 24 March 2019New research, March 11-17, 2019
Oriondestiny@1,
Your comment appears to be a political attack on this site for its efforts to improve awareness and understanding in a way that is contrary to your developed personal interests.
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Oriondestiny at 03:44 AM on 24 March 2019New research, March 11-17, 2019
This whole web site is government funded propaganda.... Climate change is a scam... There is nothing to argue and discuss. This is all leading to a big money and power grab. I can't see past the scam to even consider the fake climate change content.
It's March. The snow has melted. The Crocus's are starting to pop us as they do every year at this time. Nothing has changed. Same ole, same ole. It got down to -25 F this year. Too bad it won't kill off the mosquitos. And.. and, if it gets up to 104 F as it did in 2013, that didn't kill the mosquitos either.
So the average temperature raised 0.5 C in the last 50 years? I laugh. That is NOT climate changing. It goes from -25 F to as high as 104 F where I live in 6 month, year in and year out. Saying 0.5 C in 50 years is detrimental is a joke. I laugh you to scorn.
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One Planet Only Forever at 14:30 PM on 23 March 2019The temperature evolution after 2016 suggests hotter future
Eclectic @32,
When pointing out that the next glacial phase is due in about 20,000 to 30,000 years it could be helpful to add "Easy to get fossil fuels that have been discovered and left in the ground could be burned nearer that time to help human civilization get through that event".
By then climate science may have developed understanding leading to better ways of dealing with that event. But it would still be 'helpful to future generations' if lots of easy to get fossil fuels were found and left in the ground for a future 'true emergency (energy warming, or other helpful puprose)' rather than harming the future generations by rapidly burning them up now.
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Eclectic at 12:05 PM on 23 March 2019The temperature evolution after 2016 suggests hotter future
ThinkingMan , it's always worthwhile to step back occasionally and look at the bigger context.
Global surface temperature had been at a fairly flat plateau for (roughly) 5,000 years of the Holocene Maximum ~ which has been followed by (roughly) 5 or 6,000 years of gradual decline (related to the Milankovitch cycle of insolation). Owing to the present relatively-low ellipticity of the Earth's orbit, the next glacial phase is due in 20-30,000 years ~ and may be skipped altogether since the oceans are being unusually warmed by AGW.
The Little Ice Age, the Medieval Warm Period, the Roman Warm Period etcetera are only tiny wiggles in comparison to the multi-millennial decline in temperature.
Against this long-term decline, you can see the last (roughly) 100 years demonstrates a temperature rise which is shooting upwards like a rocket. And is now surpassing the Holocene Maximum. IMO it is beyond ridiculous for denialists to assert that our modern-day global warming is the result of a 60-year oscillation in oceanic currents.
Yet that is what some of the (more intelligent) denialists assert. No need to waste your time reading Professor Curry's blog ~ she is still suggesting that "up to" 60% of modern warming could be caused by confluence of oceanic current cycles. Quite marvellous it is, how a giant dose of "Motivated Reasoning" can so completely distort the rational thinking of an educated intelligent person.
You see rather similar bizarre thinking coming from Lindzen & Spencer & others. (And much of the remainder of denialists are still loudly proclaiming that CO2 has zero or negligible Greenhouse effect.)
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scaddenp at 08:36 AM on 23 March 2019The temperature evolution after 2016 suggests hotter future
thinkingman - I appreciate your question. It is always good to clarify so we dont talk past each other. It is also worth clarifying "cooling".
By "natural cooling forces" I understand you to mean things that would affect the temperature trend as opposed to year by year or even decadal average variation. On scale of 3-10 years, then the natural, chaotic, ENSO cycle is dominant. The upper ocean exchanges heat with atmosphere. A series of La Nina can look like cooling; a series of El Nino can look like warming. However on climatic scales (or even scales of decade), these do not affect the temperature trend. I mention this because you asked "since 1998" which immediately rings alarm bells. A lot of pseudo-skeptic arguments are based on cherry picking a big El nino event and then comparing trend after that. You can expect "since 2016" to become popular on certain websites.
Assuming you mean temperature trend and actual forcing, I can be more definitive. You could say that AGW is countering some external forcings. The Milankovich cycle has been slowly cooling for some time, though the effect is so slow that its impact on climate even over a century would be hard to determine. You could also argue that total solar irradience trends since 1990s has been slightly negative. The change in forcing again is incredibly minor comparied to measured AGW-driven changes in surface radiation. I dont see volcanic aerosols having any particular trend.
I do not see any convincing evidence for some magical 60 year/80 year cycles, especially when proponents struggle to identify a physical source.
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MA Rodger at 05:33 AM on 23 March 2019The temperature evolution after 2016 suggests hotter future
ThinkingMan @26,
You point not to a "paper" but to a 2015 blog and its author is somebody called Vaughan Pratt. It is only posted by Judy Curry on her blog-site.
Even so, it is full of enough nonsense to match that of Curry. The initial assertion (from Curry) that:-
"About 40% of the warming since 1880 occurred prior to 1950, and is not attributed to human greenhouse gas emissions."
and (from Pratt) that:-
"The importance of this period (ie late 19th century to 1950) is that it contains by far the best data we have about natural variability in the absence of significant variation in CO2."
This is pure nonsense. Examine IPCC AR5 Table AII.1.2 and you find that a third of the CO2 forcing to 2011 and almost the same proportion of 'GHG Other*' to 2011 were present by 1950. Curry's grand climate wobble is based solely on a dip and a peak in the global average temperature record. This is not insignificant & Curry is plainly wrong to suggest it is. Her grand wobble theory has no basis other than that. It is no more than curve-fitting and has no serious evidential support.
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ThinkingMan at 23:49 PM on 22 March 2019The temperature evolution after 2016 suggests hotter future
scaddenp: Do you accept or reject the possibility AGW offset natural cooling forces from 1998 to the present? And, are those specific cooling forces adequately reflected in the CMIP5 ensemble mean? Your position is not clear in your two recent posts.
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TVC15 at 18:52 PM on 22 March 2019Climate's changed before
I give much thanks to all that have helped me broaden my knowledge of global warming and especially how to deal with the denialist I've been debating for almost a year. I've not quite dealt with a denialist as the one I've presented. I agree with you MA Rodger! This denialist is as an exuberant fool relishing the chase. He is not worth a bean.
Special thanks to Michael for the link to HHoffman et al 2017.
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scaddenp at 09:08 AM on 22 March 2019The temperature evolution after 2016 suggests hotter future
The blog post happily assumes variation from the trendline is "natural variability". Huh?
Above the climate forcing used by models. Volcanoes are of course natural variability but it would be a mistake to regard the variability as unforced change. Furthermore, the effect of man-made aerosols (ie pollution) 1940-1960 remain hard to tie down.
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scaddenp at 07:13 AM on 22 March 2019Climate's changed before
TVC - first thing to remember is the old saying that you cannot reason a person out of position that they were not reasoned into. Deniers will deny. You can however demonstrate to other bystanders that their position is not based on science. You could ask if they could consider that any evidence will change their mind. Chances are the answer is "nothing".
The CO2 lags argument is already in Skpsci. See here.
https://skepticalscience.com/co2-lags-temperature.htm and this is really where this discussion belongs. The argument relies on believing you can choose which bits of chemistry and physics apply at will.In short, CO2 is both a feedback AND a forcing. Anything that causes temperature to rise will eventually cause CO2 to rise as well (and vice versa) but on timescales of centuries to a thousand years (time for ocean mixing). Our adding CO2 from emissions will eventually cause CO2 to be releassed from natural sinks making matters worse. In ice age cycle, it acts to convert a local event (change in insolation in NH around 65N) into a global event. Locally the milankovich forcing is large. If you look at MA Rodgers graph, the Milankovich forcing changes insolation at 65N by 10+W/m2 between glacial and interglacial. The forcing from doubling CO2 is around 4W/m2. The difference is that change is local for milankovich (I note the deniers examples to "prove" it was global were all NH higher latitudes), but global for CO2. I should say ditto for water vapour but feedback is much faster. Your denier is pulling a strawman argument, claiming CO2 is supposed to explain all climate change. Climate science by comparison claims that all physical laws apply at all times and climate responds to net forcing, not one single factor.
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michael sweet at 06:48 AM on 22 March 2019Climate's changed before
MA Rodger and others interested:
I think the full text of HHoffman et al 2017 is here.
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nigelj at 05:31 AM on 22 March 2019The temperature evolution after 2016 suggests hotter future
"The important outcome is: Rising CO2 levels apparently (and may have indeed) offset natural cooling forces since 1998-2000. This possible outcome supports the AGW case."
Yes it does.
The pdo ocean cycle here correlates rather well (by eye) with the bumps and dips in the surface temperature record since 1900, including the so called recent pause.
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TVC15 at 04:36 AM on 22 March 2019Climate's changed before
MA Rodger, thank you so much! I am not a climate scientist but I do hold 3 science degrees in the field of medical science. I love this site as it has helped me learn so much about areas of climate change that I was unaware of.
This denier posts walls of misinformation and rants just as you have read and since most people in the world are not well versed in science, they think he sounds great and knowledgeable. It's astounding the things he's says. He tried arguing CO2 is a dissolved and released gas in seawater, and that it's based on Boyle's Law. I was astounded and knew immediately I was dealing with a layman attempting to come off as being knowledgeable in science.
I often wonder where he gets his misinformation from.
He is constantly trying to push these concepts:
My position is that CO2 levels are irrelevant. CO2 levels are a lagging indicator. Temperatures increase, then CO2 levels rise. Temperatures decrease, then CO2 levels drop.
There are many articles that all say the same thing.
What were CO2 levels during the last Inter-Glacial?
EPICA Ice Core data for the last Inter-Glacial period shows CO2 levels never rose above 286.8 ppm CO2 (peak at 128,609 years before present).
Because CO2 levels peaked at 286.8 ppm CO2 and temperatures in Greenland were 14.4°F warmer than present and on the opposite side of Earth temperatures were 22.5°F warmer than present, you cannot claim CO2 drives the climate.
In fact, that refutes global warming.
Here we show that the south GIS was drastically smaller during MIS 11 than it is now, with only a small residual ice dome over southernmost Greenland.
https://www.nature.com/articles/nature13456
If we go back to MIS 11, we find CO2 levels peaked at 283.5 ppm CO2 at 411,071 years before present.
If you look through EPICA Ice Core Data, CO2 levels never peaked more than 292 ppm CO2 over the last 800,000 years.
Prove, with absolute certainty, that if CO2 levels were back down to 287 ppm, temperatures in Greenland would not rise another 14.4°F and temperatures in Siberia would not rise another 22.5°F.
If you are unwilling to do that or cannot do that, then you have proven global warming to be a fatally flawed theory.
Given that CO2 levels are currently in excess of 400 ppm CO2, why haven't temperatures risen?
You say they have? Yeah, 1.4°F over 140 years, but, I've already proven that temperature fluctuations of 20°F in a matter of years is not unprecedented.
I think Skeptical Science should add this denier’s myth claims to the most used climate myths. This denier makes some of the strangest claims and draws odd conclusion’s based on what appears to be cherry picking and lack of basice science understanding.
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MA Rodger at 23:36 PM on 21 March 2019Climate's changed before
TVC15 @645,
Picking up on the denialist's assertion that his position would be supported by "any peer-reviewed paper," I have been unable to find the full text of Hoffman et al (2017) 'Regional and global sea-surface temperatures during the last interglaciation' (which is of course one such paper) but its abstract (below) doesn't give any room for the denialist's bold assertions about blindingly hot Eemian global average temperatures which @642 the denialist describes as "15.3°F warmer than now" or +8.5ºC relative to today.
"The last interglaciation (LIG, 129 to 116 thousand years ago) was the most recent time in Earth’s history when global mean sea level was substantially higher than it is at present. However, reconstructions of LIG global temperature remain uncertain, with estimates ranging from no significant difference to nearly 2°C warmer than present-day temperatures. Here we use a network of sea-surface temperature (SST) records to reconstruct spatiotemporal variability in regional and global SSTs during the LIG. Our results indicate that peak LIG global mean annual SSTs were 0.5 ± 0.3°C warmer than the climatological mean from 1870 to 1889 and indistinguishable from the 1995 to 2014 mean. LIG warming in the extratropical latitudes occurred in response to boreal insolation and the bipolar seesaw, whereas tropical SSTs were slightly cooler than the 1870 to 1889 mean in response to reduced mean annual insolation." [My bold]
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ThinkingMan at 22:50 PM on 21 March 2019The temperature evolution after 2016 suggests hotter future
Scaddenp: Will reply at another time.
All: Parts of this article are relevant to the concept. https://judithcurry.com/2015/11/03/natural-climate-variability-during-1880-1950-a-response-to-shaun-lovejoy/
Yes, I know Judith Curry's name will cause some followers of this blog to recoil. Pls read the paper, nevertheless.
The 2nd & 4th graphs are pointed out because a picture is worth1000 words. The 4th graph shows that since 1950, rising atmospheric CO2 levels explain well a long term temperature trend. The 2nd graph shows the difference between recorded temperatures and temperatures consistent with contemporaneous CO2 levels. The difference is attributed to "natural variability". Pls note the downward trend in natural variability from 2000-2012. Whether the downward trend is caused by a cycle or natural events with unpredictable timing is a side issue. The important outcome is: Rising CO2 levels apparently (and may have indeed) offset natural cooling forces since 1998-2000. This possible outcome supports the AGW case.
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MA Rodger at 18:20 PM on 21 March 2019Climate's changed before
TVC15 @645,
The denialist appears to me as an exuberant fool relishing the chase. He is not worth a bean.
On the source of his numbers - You could ask him if it is that he cannot remember where these numbers are allegedly lurking and thus he sets out so many possible sources. Or is he saying there are so many sources that he is spoilt for choice? All we need is one credible reference to be able to judge his preposterous claims on interglacial global average temperatures. Perhaps he should also set Wikipedia straight. They, despite using Antarctic EPICA ice core data unajusted, still have nothing like the temperature record alleged by this denier in their account of the Geological Temperature Record.
The rest of his rant is basically saying there is interglacial warming yet to appear in the present Holocene interglacial, and this based on the level of deglaciation at the height of the Eemian deglaciation. Perhaps he can set out the mechanism he sees as providing this warming-yet-to-appear.
In sensible speak, the reason for the Eemian being warmer than the Holocene is down to the reduced glaciation driven by high latitude Northern insolation. It is, of cource, a dynamic system so the timing of this insolation within the ice age cycle is critical. The denialist seems to fail to grasp that timing is everything and is bogged down by considering the duration of any particular swing in the Milankovitch cycles.
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TVC15 at 15:05 PM on 21 March 2019Climate's changed before
Scaddenp and MA Rodger,
I'm starting to think this denialist is being paid to spread myths and move goal posts.
When I asked for references I was told that its a "government source, or from Nature, NOAA, National Geographic or any peer-reviewed paper"
So essentially they could not provide a concrete reference for the nonsense numbers.
I also looked for a timeline of the last 8 interglacial global temps and could not find a good source.
Below is a typical argument of a denialist.
It's not just Greenland. It's also Baffin Island:
From applications of both correspondence analysis regression and best modern analogue methodologies, we infer July air temperatures of the last interglacial to have been 4 to 5 °C warmer than present on eastern Baffin Island, which was warmer than any interval within the Holocene.
Vegetation and climate of the last interglacial on Baffin Island, Arctic Canada
4°C to 5°C corresponds to 7.2°F to 9.0°F
And in eastern Siberia:
Our pollen-based climatic reconstruction suggests a mean temperature of the warmest month (MTWA) range of 9–14.5 °C during the warmest interval of the last interglacial. The reconstruction from plant macrofossils, representing more local environments, reached MTWA values above 12.5 °C in contrast to today's 2.8 °C.
12.5°C is 22.5°F warmer.
So, this is not a regional phenomenon occurring only in Greenland. It's global.
And, if you've noticed, the climate-nutters refuse to acknowledge the science, because it contradicts their belief system.
The Milankovitch Cycle has nothing to do with it.
Originally, Glacial Periods lasted 40,000 to 42,000 years and Inter-Glacial Periods lasted 12,000 to 15,000 years.
What does that have to do with the Milankovitch Cycle?
Absolutely nothing.
Oh, wait a minute, I get it....you're looking at the 40,000 to 42,000 year Glacial Period and thinking it jives with the 41,000 year Cycle, which is just one of three Cycles.
It should be very obvious, because peak-to-peak, the cycle is 52,000 to 57,000 years.
I often wonder where these types of minds come from. It's interesting that creationists argue in the same manner. I often wonder how the human mind can allow itself to be completely deluded with self-righteous beliefs.
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John Hartz at 09:42 AM on 21 March 20192019 SkS Weekly Climate Change & Global Warming News Roundup #11
citizenschallenge: You conclude your most reponse to me with:
Moral of the story stop focusing on tiny uncertainties - Redirect the dialogue back to the known certainties - Because they certainly tell us enough!
Which is exactly why Bernie Sanders shouldn't have said what he did about tornados and climate change.
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scaddenp at 07:13 AM on 21 March 2019The temperature evolution after 2016 suggests hotter future
Invoking unspecified "natural cycles" does not further understanding. There are certainly natural "cycles" or more likely quasi-periodic variations at work. It is important to distinquish between internal variability (energy moving around in an unevenly heated water-covered planet) and variability in climate forcing (eg milankovich cycles, solar output variation, volcanic aerosols). Internal variability is things like the ENSO cycle which is dominate cause of intra-decadal variability. These are unpredictable, (chaotic) and affect climate largely by heat exchange between ocean and atmosphere. Climate models have no skill in predicting these variations. When you see a graph like:
then the grey area is the space defined by multiple individual model runs. Any observational line within the grey area is compatiable with the model output. If you look at individual runs of the climate models, then you see the many possible outcomes. This post covers what the models are actually telling you. There is no skill expected at decadal predictions, but the model mean does a pretty good job at prediction the 30-year (climate) trends.
While small amounts of heat transfer from oceans affect temperature, blaming warming on heat coming from the ocean while ocean heat content is increasing is "voodoo economics". If some unknown ocean "cycle" is providing the heat, then how come the ocean is getting hotter?
Variation in external forcings is another story. The milankovich forcing is readily calculated and we are warming despite a very slow negative orbital forcing. Solar has quasi-periodic cycles but we can directly measure solar input at top of atmosphere. You cannot claim a solar cause when solar input is flat or declining. Volcanoes of cource are unpredictable but models must put in a "average" changes to aerosol forcings or the models would run too hot. You can always re-run models with actual forcings for solar, volcanic etc and this is done.
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MA Rodger at 05:52 AM on 21 March 2019Climate's changed before
TVC15 @642,
What this denialist is saying in proper numbers is that seven previous interglacials had global average tmperatures between 19ºC & 23ºC when present global averages are put at 14.7ºC. So that would put these prior interglacials +4.3ºC to +8.3ºC relative to today.
There is a graph in the screed below this thread showing none of the past four interglacials topping +4ºC above the 1960-90 average. (Two are a tad above +3ºC and two a tad above +2ºC). But the graphic is unreferenced so not that helpful but indicative that the denialist is talking nonsense. (I have the thought that the graph looks a bit like Vostok ice core data which means it still requires adjusting for polar amplification to provide global temperature.)
Yet even the EPICA ice core data (which covers back to eight previous interglacials) doesn't manage the '+4.3ºC to +8.3ºC relative to today' for seven prior interglacials. Only five of last eight were warmer than 'today' and the warmest, the Eemian, was +4.8ºC which should be perhaps at least halved to give a global value and account for polar amplification.
One of the problems with identifying a Greenland temperature for the Eemian is that Greenland pretty-much melted out in the Eemian. Yet to see this as a global temperature thing is a step too far. Yes, it would take very little increase in global temperature to set Greenland melting out (something like +1.5ºC above pre-industrial) but the Eemian had a far stronger Milankovitch cycle warming the Arctic which would suffice just as well, even with a lower global average temperature.
Generally though, the denialist is spouting nonsense numbers. So the questions of import - Where does he get these nonsense numbers? Which nonsense factory?
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nigelj at 05:33 AM on 21 March 20192019 SkS Weekly Climate Change & Global Warming News Roundup #11
Citizenchallenge
I havent followed this issue too much but I gather Climate Feedback "corrected" Bernie Sanders on tornados and did so in a very extensive and fairly hyper critical sort of way.
I think they probably did this to avoid sceptics and the right wing accusing them of ignoring mistakes and suffering from tribal group think. So climate feedback were trying to be very "proper and objective". I think "warmists" do need to ensure we don't ignore bad science.
Unfortunately it kind of distracts from the big issues and undermines Sanders. So I know where you are coming from. Damn frustrating. Climate feedback should have been smarter and kept it short and simple and less hostile towards Sanders "Theres no evidence climate change is making tornados worse yet but several models predict it will cause changes (this is my underdtanding). Details can be found in.." So dont make a big issue of it.
I think messaging climate science for the masses is very challenging. If its too complicated and nuanced many peoples eyes will glaze over. If its too simple it will bore people with a scientific curiosity. This website does do quite well by having basic and advanced explanations.
There are no magic answers. Style of communication is going to obviously depend on the audience and must be tailored to fit.
There is a lot to be said for keeping things simple, especially if media interviews are short. We had a prime minister (sort of a similar role to president) who was a brilliant communciator. He kept the message simple, but with just enough of the critical details to give substance. There was no waffle or generalisations either.
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william5331 at 04:43 AM on 21 March 2019Editorial cartoonists lampoon, praise Green New Deal
It's just ridiculous. Greening America energy, repairing her infrastructure, improving health care and so forth would create jobs, increase the tax take, reduce welfare payments and in every way revitalize the sagging economy of the USA. The benefits would be primarly to the people rather than the uber rich and perhaps this explains all the propoganda against the Green New Deal. As long as politicians depend on the financing of their next election campaign from the vested interests, even the ones that pay lip service to the idea will never do anything substantial to push it forward.
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One Planet Only Forever at 03:48 AM on 21 March 2019Humans are greening the planet, but the implications are complicated
jzk,
This in not 'my website'.
My understanding is that it is a website developed to improve understanding regarding climate science. Its focus is clearly on counter-acting attempts to diminish the awareness and understanding of the future implications of the unsustainable and damaging developed human activity related to climate science. It does that by overcoming and correcting misleading claim-making.
I have seen many other comments attempting to claim that information presented on this site is political rather than 'just science'. I question the motives of anyone making such a claim.
Improving awareness and understanding related to climate science is undeniably being deliberately compromised by people who wish to maintain beliefs that the global burning of fossil fuels is acceptable, does not need to be rapidly curtailed (some even try to claim it is 'helpful' without providing any proof that a net-benefit for future generations is being created). And hinting that increased Greening is occurring and that is a Good Thing is a politically misleading claim-making effort (an effort that could be pursued if the article title had not correctly qualified the incorrect belief in the 'benefit of increased Greening due to increased CO2').
In addition to the questions raised regarding the greening in the article (the reason its title justifiably includes a 'but'), the undeniable awareness and understanding (science thinking if you wish) is that the greening discussed in the article does not neutralize the global warming climate change impacts of burning fossil fuels. I would argue that that should have been included in the article.
A related undeniable fact is that any perceptions developed from an unsustainable and harmful activity, like the burning of fossil fuels, are 'unsustainable'. That fact nullifies your attempt to claim that articles describing the negatives of fossil fuel burning should include a 'but' about how beneficial they are (they are not creating a sustainable benefit).
No part of those two undeniable understandings is 'political', except for the political attempts to deny them.
A better title may have been "Though increased CO2 can be seen to be increasing plant growth in the past, it would be incorrect to claim that the observed increased plant growth due to increasing CO2 in the atmosphere means that the increase of CO2 due to fossil fuel burning is creating a sustainable improvement for the future of humanity".
The improvement of awareness and understanding that is required to develop sustainable improvements for the future of humanity (the real value of science), cannot occur without a holistic assessment. And the only positive and negative evaluation that has merit is the 'future positives and negatives'. Evaluating current generation positives with future generations negatives is an undeniable incorrect evaluation. No harm should be done to Others, and the future generations are a massive group of Others (that is not political or scientific, it is the fundamental of ethics and morals that should govern everything humans do).
As you may now be aware, I replied to your comment the way I did because I personally considered it to be 'politically motivated, rather than scientifically motivated'. Your reply to my reply appears to have confirmed my initial impression.
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ThinkingMan at 03:25 AM on 21 March 2019The temperature evolution after 2016 suggests hotter future
To all: TY for the informative feedback.
The point some APPARENT cycles are NOT genuine cycles is valid.
It is also the case that genuine cycles with differing periodicities can cancel, mute or accentuate their expression.
The above combined with the many natural forces influencing temperature, climate ... makes validating and explaining cycles a brain busting challenge.
"Proving" AGW offset natural cooling forces from 1998 to the present will be at least as challenging. Timing (reasonable start dates for a possible natural cooling phase) is only one feature that prompted me to raise the possibility. A second is: The approx. 0.2C/decade rate for AGW is similar to the rates at which temperature trended downwards from 1880 to 1910 and the early 1940s to the mid 1970s. The dates are approximate. A third is: The AGW concept may be valid despite the fact climate models as a group overstated the amount the amount of warming over the past 20 yrs or so.
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jzk at 01:48 AM on 21 March 2019Humans are greening the planet, but the implications are complicated
One Planet Only Forever,
The qualifying nature of the article and your post is fine if you are political website looking to advance a postion. That is not science. Science has no position. Potential downsides to increased greening? That is for another article. Are there currently downsides to the increased greening? Are current crops lower in nutritional value than crops from 30 or 40 years ago? Those are valid scientific questions. Again, have whatever kind of website you want. Just be up front about it. Further, in arriving at any conclusion about a particular course of action, one must honestly evaluate the positves and the negatives. If you can't do that, then who can take your conclusion seriously?
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citizenschallenge at 01:05 AM on 21 March 20192019 SkS Weekly Climate Change & Global Warming News Roundup #11
correction: Sad. Nothing humorous about it.
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One Planet Only Forever at 00:56 AM on 21 March 2019Humans are greening the planet, but the implications are complicated
jzk,
I will open with a Good Reason to 'qualify the greening benefit of increasing CO2". The article includes the following point.
"About one quarter of the carbon dioxide placed annually into the atmosphere by fossil fuel combustion has been hypothesized to be removed through enhanced vegetation growth and accumulation of organic carbon in land ecosystems."
That means that increased CO2 from burning fossil fuels is only partially affected by increased plant growth. The greening does not fully neutralize the new CO2 introduced to the recycling environment by burning buried ancient hydrocarbons. As a result, climate change impacts of the warming that are harmful to future generations and difficult for them to adapt will happen (is happening) in spite of the greening.
The article also included points about the potential that the added greening may not be helpful for humans.
I will close with a comment regarding "..."but fossil fuel provides needed electricity for the world's poor" or any other benefit."
Any developed perceptions of benefit from a harmful and unsustainable activity like the burning of fossil fuels is undeniably unsustainable into the future, and harmful to the future. So, the continuation of attempts by people to personally benefit from burning fossil fuels can be argued to be creating a larger future correction that will require very significant corrections of developed perceptions of status and corrections of perceptions of what is Helpful.
We already see the reality of that understanding. The lack of responsible actions by the supposed leaders of the planet through the past 30 years has created more future harm, and has created a requirement for a more dramatic correction of what has developed irder to responsibly limit the harm done to the future of humanity.
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citizenschallenge at 00:54 AM on 21 March 20192019 SkS Weekly Climate Change & Global Warming News Roundup #11
John: This isn't about the minutia of scientific consensus !
This is about explaining what science knows to unscientific people - this is not about the inner workings or arguments amongst scientific community. Why won’t you acknowledge that importance distinction?
Shouldn't we be Communicating WHAT IS KNOWN - and creating a clarifying dialogue that converts our global climate engine from some untouchable abstract notion to something tangible, that carries some visceral enlightenment that leads to a real sense of awareness.
ClimateFeedback's did not do that. Below the screen shot I took was another explanatory paragraph that crammed nearly 300 words into it. That may work great for serious scientists who are trained to digest copious amounts of written information, but it doesn't work for the rest of us regular mortals.
John, you conclude that there is no scientific consensus between the man-made climate change and the frequency and intensity of tornados in the US.
Well than what about the damned consensus that extra heat is accumulating in our climate system? Or the consensus that our current biosphere is custom fitted to our planet's heat budget and that provided radically more energy to the system will be reflected in increasing destructive weather phenomena? Why not redirect focus?
Seems to me in real life when we find ourselves in the weeds (so to speak) - the sensible thing is to pull back from our overwhelmingly confused situation and back into territory that we understand. Then we start with what we know for certain and continue forward with that, in light of the new lessons learned.
What you keep ignoring about my message is: Stop focusing so much on the uncertainties. Don't talk to kindergartners as thought they are thoughtful adults. Come on, look at whom America* gave it's presidency to - that is not the conduct of an introspective thoughtful people. (* not that others are doing much better)
That's an indication of a people who do things by shallow impulse, swayed by pretty one-liners and gut feeling, rather than digesting substantive words and seeking out information.
You may be correct that there is no scientific consensus regarding "frequency and intensity" - What I take issue with is advising to toss up our hands in the air - list all the minutia you can think of to prove how thoroughly scientists are investigating this and call it good.
Never noticing your crowd is walking away more confused than clarified - that my dear friend is exactly what plays into the hands of climate science denier! Those who created this phony tornado distraction expressly to confuse and waste time, to begin with.
Now you tell me that's the best we can hope for - and you wonder why I'm disillusioned at the powers that be.
Considering the Kochs' have been doing all the winning of passionate hearts and minds these past decades, even as the evidence does nothing but become more solid, I find it humorous that you are so entrenched in repeating the same sloganeering that hasn't worked for oh so long.
Moral of the story stop focusing on tiny uncertainties - Redirect the dialogue back to the known certainties - Because they certainly tell us enough!
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jzk at 23:06 PM on 20 March 2019Humans are greening the planet, but the implications are complicated
Why do you write "but" in the title? If there is evidence about the benefits of increased CO2, why not let it stand on its own? When you cover a topic about the negatives of CO2, do you say "but fossil fuel provides needed electricity for the world's poor" or any other benefit? Or do you just let that stand on its own? One way shows bias. The other way shows science.
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Postkey at 20:10 PM on 20 March 2019CO2 lags temperature
“Tectonics in the tropics trigger Earth’s ice ages, study finds
Major tectonic collisions near the equator have caused three ice ages in the last 540 million years. . . .
Over the last 540 million years, the Earth has weathered three major ice ages — periods during which global temperatures plummeted, producing extensive ice sheets and glaciers that have stretched beyond the polar caps.
Now scientists at MIT, the University of California at Santa Barbara, and the University of California at Berkeley have identified the likely trigger for these ice ages.
In a study published today in Science, the team reports that each of the last three major ice ages were preceded by tropical “arc-continent collisions” — tectonic pileups that occurred near the Earth’s equator, in which oceanic plates rode up over continental plates, exposing tens of thousands of kilometers of oceanic rock to a tropical environment.”
http://news.mit.edu/2019/tectonics-tropics-trigger-ice-ages-0314 -
Kevin C at 18:02 PM on 20 March 2019Holistic Management can reverse Climate Change
Just a quick note: I spent 6 hours doing research based on 1 comment yesterday. I've started on PV's comments, which contain some very useful context which help understand some of RB's paper list.
I can only devote 1-2 hours a day to this over the next 3 days, but I am hoping to make a further contribution either today or tomorrow.
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scaddenp at 11:44 AM on 20 March 2019Climate's changed before
Artemsis, the proposition is puzzling and it would help if you could get more information on what informs your denier. Estimating a global mean temperature through the Quarternary is not a simple proposition and it looks to me as if a no. of data sources have been mis-interpreted. The temperature of Greenland at LIG cf present might also be confused about what is "now" (The meaning of 0BP in ice core records). In short, we need the references used by the denier that back the above claims.
Beyond that there is some sleight-of-hand in the argument. Climate does not change on its own. It changes in response to changes in net forcings and the ice ages are no different. The ice age cycle is due to orbitally-driven changes in the distribution of solar insolation in the northern hemisphere, which are amplified into global change by CO2 and albedo feedbacks. Temperatures in NH polar regions can indeed be warmer in interglacials with lower CO2 because the incoming insolation for that region is much higher than today. This is not a global change however. More importantly, the milankovich forcing is now decreasing. Without our anthropogenic CO2 we should be slowly cooling. It is important to realize however that this change is very slow - milliwatts per century - compared to emission CO2 forcing which is more like 1W per century. Even without our emissions, the next glacial would have been 50k into future. (Berger and Loutre 2002)
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