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Comments 9501 to 9550:
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Brockagh at 19:02 PM on 8 October 2019The science isn't settled
Regarding the plane falling out of the sky analogy... If you had to get on one of two planes, would you pick the one with a tem percent chance of survival or the one with a 90 percent chance of survival.
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nigelj at 10:24 AM on 8 October 2019How the Greenland ice sheet fared in 2019
OPOF @4, yes its always worth a try rebutting climate denialism and explaining the bigger picture. Of course denialists will never or rarely change their minds in public in an internet discussion, because nobody likes to loose face, and this creates an impression denialists never change their minds, but some of them probably do change their minds. Here is an example of some who have:
www.theinertia.com/environment/heres-how-the-evidence-changed-a-climate-change-skeptics-mind/
www.theguardian.com/science/2012/jul/29/climate-change-sceptics-change-mind
Of course PC is also quite right. You get a lot of that.
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One Planet Only Forever at 10:10 AM on 8 October 2019How the Greenland ice sheet fared in 2019
nigelj and Philippe,
My response is: By being aware of the fuller story you can respond quicker to anyone who tries to use the cherry-picked claim (or any other misleading marketing tactic). Rapidly correcting someone by introducing them to information they were unaware of, or did not want others to be aware of, can be very effective.
Of course, some people will just get angry. That is a common response to being corrected. But, as is often pointed out in comments here, others may be watching who benefit from the interaction. They get to see who can be more trusted to tell the fuller story and who tries to promote or maintain a misleading made-up belief.
That knowledge of the fuller story can also be used to determine how much an information provider may have been influenced by Edward S. Herman's Propaganda Model presented in the book and movie "Manufacturing Consent".
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Philippe Chantreau at 09:18 AM on 8 October 2019How the Greenland ice sheet fared in 2019
There is no answer because there is no good way to deal with those who argue in bad faith and whose only guiding principle is "anything goes."
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richieb1234 at 08:48 AM on 8 October 2019It's the sun
MA Rodger: Thanks for the additional information.
My only point is that the "myth" thermometer on the left of the front page is a key part of the SS website's message. When a viewer clicks on one of those myths, they should find a blatant statement of the myth from a climate denier. The BBC quote doesn't pass that test.
The quotes above from Whitehouse also don't show he is claiming that "it's the sun." In these quotes, Whitehouse is apparently claiming that the sun was a big factor in past climate changes, but not recent changes. That is an accurate claim.
I just think there must be a better quote somewhere to illustrate this myth.
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nigelj at 06:34 AM on 8 October 2019How the Greenland ice sheet fared in 2019
OPOF @1, I was thinking exactly the same thing. Its a perplexing problem because science is complex like this, but this provides so many ways denialists can cherry pick and attack. Yet is the science is not fully and openly discussed in all its complexity and nuance, that's not good either. There does not seem to be an easy answer to this dilemma, other than the slow unfolding of increasingly obvious climate change, that makes the denialists look increasingly stupid.
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Estoma at 06:03 AM on 8 October 2019Climate's changed before
Thank you Danial for the graphs. You come up with lots of good stuff.
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One Planet Only Forever at 02:31 AM on 8 October 2019How the Greenland ice sheet fared in 2019
Another detailed presentation that is likely to have cherry-picking applied by climate science deniers and delayers.
The reported Surface Mass Balance is all they need to, want to, see and hear about. It indicates that Greenland ice is increasing, as long as the fuller story is never sought out.
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allan savory at 01:39 AM on 8 October 2019New rebuttal to the myth 'Holistic Management can reverse Climate Change'
As this is your first post, Skeptical Science respectfully reminds you to please follow our comments policy. Thank You!
I have only now become aware of your criticism of my work addressing global desertification and climate change. I seriously value and share your motive as a very sceptical scientist myself, but am sorry you did not treat this more seriously. In what is frankly extremely sloppy scholarship you state dogmatically - " Quite simply, it is not possible to increase productivity, increase numbers of cattle and store carbon using any grazing strategy, never-mind Holistic Management." If you are serious, as I am, about global desertification and climate change, then please do not judge sixty years of work published in the 3rd edition of the textbook Holistic Management, on a 20 minute talk covering only one main point. That point being that only livestock and the holistic planned grazing process (or better when developed) can now save civilization as we know it.
I have no intention of debating you here when you have not even read the book. For your interest when you do and we engage in discussion, please take note of the policy chapter. Firstly that will get you realising the Holistic Management framework that enables us to manage complexity at any level from household to governance is not some sort of grazing strategy as you believe. How would you use any grazing strategy to analyse any or all of the US government’s natural resource and other policies?
As you read, you will learn that far-sighted officials in the USDA commissioned me over two years to put some 2,000 scientists and others through a week of training in the use of the Holistic Management framework. Those came from all land management agencies, faculty members from US universities, World Bank, USAID and more and they brought hundreds of their own policies to the training. They, not me, analysed their own policies and found not one that would work and would not lead to unintended consequences. One group in training made a unanimous agreed statement we published –“We now recognize that unsound resource management is universal in the United States”. I am sure you recognize that such analysis is simply not possible with what you have mistakenly assumed is Holistic Management of which you are critical.
Further information for you. In the training of that large sample of scientists from some with basic degrees to Professors and others with two or more higher degrees, we allowed an hour every day of the week for them to concentrate entirely on finding any flaws they could in either the logic or science in Holistic Management framework that enables us for the first time to manage complexity. Early on this helped mainly clarify what people were battling to grasp and also highlighted a couple of logical flaws thus enabling those thousands of scientists to assist us in fine-tuning the framework, and the Holistic Planned Grazing process used when livestock are required to reverse desertification. And as I explained in the TED Talk you criticise, only livestock can now save civilization as we know it. Even if you forget entirely about our destabilisation of the climate and think only of global desertification that alone has destroyed many civilizations and now poses a global threat. And if you or any scientist you know anywhere in the world can explain how we could prevent desertification, or reverse it, using all the tools available to us in our reductionist management then please do so. As you know, we only have technology, fire or conservation (resting the environment to allow recovery). Other than that all the world’s scientists have ever come up with is using technology to plant trees, shrubs or grasses. Two of these fire and resting the environment lead to global desertification and no technology even imaginable can ever restore rapid biological decay over about two thirds of the world’s land every year. So if you have some other tool humans could use please help us by telling the world. Only today have I been photographing the severe desertification taking place in the truly vast teak forests around me in Africa – larger than some countries in Europe – and wishing I had the armchair critics to explain what point there would be in planting more trees in such dense desertifying forests.
Please read the book and then discuss if need be what you find wrong in the Holistic Management framework or its application to manage complexity in any walk of life. And by the way here we have done what you say is impossible and we have the most amazing regeneration of the land after 16 dry years with this the worst in memory and we did this by increasing from 100 head of cattle to 500 and now are having to increase to 1,000 just to keep pace with the production of the land. So what you say is impossible is being done and you are welcome any time to visit. Have a look at this one minute video https://youtu.be/ntzCnpYhM3I -
Daniel Bailey at 01:17 AM on 8 October 2019Climate's changed before
"I was unable to find temperature graph for the world outside of the Arctic that went beyound 2000"
That can seemingly be an obstacle, but global reconstructions are becoming more common, depending upon the time period you're interested in. For example, these are useful summaries (sources used listed on each):
As always, clicking on the images should make them bigger.
Images from Bruce Railsback's Fundamentals of Quaternary Science.
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MA Rodger at 00:38 AM on 8 October 2019It's the sun
Further to #1272.
The link to that "latest analysis".
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MA Rodger at 00:37 AM on 8 October 2019It's the sun
ricieb1234 @1271,
Do note that the author of the BBC item quoted in the 'Myth' is David Whitehouse who is now known to be a fully paid-up member of the denialist squad. His take-away message in 2004 was:-
"This latest analysis shows that the Sun has had a considerable indirect influence on the global climate in the past, causing the Earth to warm or chill, and that mankind is amplifying the Sun's latest attempt to warm the Earth."
Yet this "latest analysis" informing the 2004 BBC article by Whitehouse concludes with the warning:-
"we point out that solar variability is unlikely to have been the dominant cause of the strong warming during the past three decades."
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Estoma at 23:58 PM on 7 October 2019Climate's changed before
I figured the genisus was "from the strong & steady rise with a clear ongoing causation by CO2." What flumoxed me was that the warming had occured at light speed; world wide from what I read. I didn't realize that had been any case like this during this inter glacial period. I'll have to add a cavet from now on when I make the unprecedented warming statement.
It appears that today's temperature is still higher than it was 13,000 years ago but I was unable to find temperature graph for the world outside of the Arctic that went beyound 2000.
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Eclectic at 23:31 PM on 7 October 2019Climate's changed before
Estoma @790 ,
I am not sure whether you are comparing arctic-localized (e.g. Greenland ice-core temperature proxies) changes with worldwide changes of smaller degree.
There were also steep rises in Greenhouse gasses (especially methane) and giant meltwater pulses affecting sea-level & the oceanic heat transfer from the tropics. All producing rapid fluctuation (see the Younger Dryas ). Still, one needs to ask: what caused the melting of land ice-sheets ~ if it wasn't caused by cumulative effect of gradually increasing Greenhouse effect? (That is a question that the "skeptics" don't wish to ask.)
The present-day rapid worldwide warming is not part of a transient up-and-down fluctuation, but is a strong & steady rise with a clear ongoing causation by CO2. World temperature has (compared with the gentle & slight variations of the past 10,000 years of the Holocene) now abruptly risen higher than the Holocene Maximum and is still rising steeply. And has occurred at a time (of roughly 5,000 years' duration) where the natural background tendency is toward ongoing global cooling.
Altogether, the two cases (of B-A events versus nowadays) are so very different in their long-term importance, that it is perfectly fair to say that current-day gobal warming is unprecedented in its character ( and in its human causation !! )
I think your "skeptic" is indulging in some Motivated Reasoning, and playing with words, in order to conceal the plain physical truth of what is happening globally.
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richieb1234 at 22:21 PM on 7 October 2019It's the sun
This quote from BBC is misleading. The full quote is:
"The data suggests that changing solar activity is influencing in some way the global climate causing the world to get warmer. Over the past 20 years, however, the number of sunspots has remained roughly constant, yet the average temperature of the Earth has continued to increase."
That's a pretty fair description of the situation in 2004, when the BBC article appeared. The professor they quote is also right to state that solar activity in the past 60 years exceeds any period of time in the last millennium.
I suggest you find a skeptic quote that actually does incorrectly atribute recent rises in global average temperature to increases in solar activity. The BBC quote doesn't.
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Estoma at 21:54 PM on 7 October 2019Climate's changed before
Bølling-Allerød seems to be a period when rapid warming far beyound today's was powered by heat from warm waters originating from the deep North Atlantic Ocean. It seems to have nothing to do with CO2. This was pointed out to me by a skeptic after I claimed that present day warming is unprecented. Reading up I discovered that from what researchers could determine the temperature rose more than a degree in less than a year and 3 to 4 degrees Celcius over a short period of time. Needless to say I was surprised by this as well as finding nothing in the Skeptical Science search.
Can you recommend an article on the subject.
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MA Rodger at 19:24 PM on 7 October 2019Welcome to Skeptical Science
carol.l.dona @67,
The paper you cite is available on-line - Eyring et al (2019) 'Taking climate model evaluation to the next level'. Its message is that the increased number and complexity of models will require better evaluation of the models or we will be drowned in a wider spread of model results.
"The growing number and complexity of models, the expanding suite of outputs they produce, the multitude of downstream applications and the growing availability of observational datasets drive a need for more routine and systematic evaluation, utilizing a comprehensive set of existing model performance metrics and diagnostics. Newly developed CMIP evaluation tools [18,19] will ultimately enhance our ability to identify model errors, to investigate their causes and to quantify and potentially reduce projection uncertainties.
"In this Perspective, we summarize key advances since AR5 and key scientific opportunities for improving climate model analyses that will be assessed in the AR6. Our focus is on gaps in the understanding of systematic errors, the development of CMIP model evaluation tools, emergent constraints and weighting methods. We also address the need for more user- and policy-oriented model evaluation at the regional scale required for impact studies. Finally, we discuss how the scientific community might provide more robust climate model information and more tightly constrained model projections."
I cannot see any meaty reviews of the paper, nothing more than describing what it is about (eg here). I also note it has alrady been cited 14 times according to Google Scholar.
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Eclectic at 13:18 PM on 7 October 2019Welcome to Skeptical Science
Carol @67 ,
it would be helpful if you gave some indications of your initial thoughts based on your own general knowledge of modelling. And on what practical benefits might be expected from an examination of Eyring's ideas. [ Like you, I have only read the paper's Abstract and some minimal commentary. ]
Pragmatically, climate models seek to assess climate sensitivity (transient and equilibrium). As you will find elsewhere in SkepticalScience articles, the paleo climate evidence points to an ECS of around 3 degrees for CO2 doubling. And the modern historical evidence (planetary surface temperatures during the past 150 years) shows a rise of nearly 1K for a CO2 rise of "halfway to doubling" ~ which indicates a Transient CS of nearly 2K . . . and presumably an ECS close to 3K , as well.
As Greta Thunberg might say :- We should be putting on our running shoes in dealing with the global warming, regardless of whether the latest cimate models come up with an ECS of 2.5 or 5 degrees. ( The latter figure does seem surprisingly high, and may as critics suggest, derive from inaccurate cloud factors. )
2.5 degrees is quite bad enough !
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carol.l.dona at 12:05 PM on 7 October 2019Welcome to Skeptical Science
As this is your first post, Skeptical Science respectfully reminds you to please follow our comments policy. Thank You!
I believe I am following your comments policy - please let me know if otherwise.
My comment is a question. Have you performed a review of the following: the 'Perspective' paper in Nature Climate Change, 'Taking climate model evaluation to the next level', by Veronika Eyring and others? I have performed a fair amount of modelling but not in climate change. I generally understand her point (taken from the abstract - the article was only available for purchase on-line) of weighting heavier the model results that best match the data as opposed to the results from models that are poorer matches to the data. However, I have not seen a review of her paper and technique. Also I have not seen any application of her proposed technique to the combining of modelling results from groups of climate change models. I would appreciate your opinion and review and reference to any other reviews that have been made of her paper. Thank you.
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nigelj at 08:02 AM on 7 October 20192019 SkS Weekly Climate Change & Global Warming News Roundup #40
The five: Donald Trump’s attacks on science.
The US president is a climate-crisis denier, but it is not the only field in which he is at odds with scientists and their work
Last week, a report by US campaign group the National Task Force on Rule of Law and Democracy, compiled by ex-government officials, concluded that under the Trump administration that there were now “almost weekly violations” to the impartiality of scientific research.
Conservation cut
In April the Trump administration withdrew funding for the Landscape Conservation Cooperatives, a large and successful conservation programme that tackled issues such as the climate crisis, species extinction and energy security. Sixteen of the original 22 research centres have now been dissolved or are on an indefinite “hiatus”. This was in defiance of instructions from Congress, which had approved $12.5m of federal funding for the cooperatives.
Weather blackout
Donald Trump’s government has refused to publicise dozens of studies from the US Department of Agriculture that examine the impact of the climate crisis. Agriculture secretary, Sonny Perdue, has previously expressed scepticism about climate change, believing it to simply be due to “weather patterns”.
Climate censorship
In June, it was reported that the White House had tried to stop Dr Rod Schoonover, a senior intelligence analyst, from discussing climate change when delivering congressional testimony. The reason given was that the science was not aligned with the views of the Trump administration.
Short-term approach
James Reilly, the director of the US Geological Survey (USGS), has ordered that scientific assessments produced by USGS use climate models that only track the possible impact of climate change until 2040, rather than until the end of the century, as they had done previously. The second half of the century is likely to see the most dramatic impacts of global heating.
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Rob Honeycutt at 12:50 PM on 6 October 2019CO2 was higher in the late Ordovician
dueskept... If I understand correctly, it's less about evidence than it is about physics. The Sun converts hydrogen to helium and as it does this, at very predictable rate, solar output increases.
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Philippe Chantreau at 11:06 AM on 6 October 2019CO2 was higher in the late Ordovician
dueskept,
The 4% lower bit in the OP has an active link to Feulner (2012) in Review of Geophysics, 50 (2). Ther article contains multiple other references, that are themselves links.
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dueskept at 08:24 AM on 6 October 2019CO2 was higher in the late Ordovician
The article says "During the Ordovician, solar output was 4% lower than current levels".
How strong is the evidence that solar output was lower during the Ordovician? Can you please point out to the evidence? Thank you in advance.
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nigelj at 06:11 AM on 6 October 20192019 SkS Weekly Climate Change & Global Warming News Roundup #40
The internet is full of climate denialism that creates the impression of an equally divided opinion on the climate issue, but polling shows most people do accept humans are altering the climate. Therefore its very likely a small number of paid lobbyists dominate the internet, and can have a disproportionate impact on perceptions. I hope politicians and other decision makers appreciate this.
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nigelj at 05:53 AM on 6 October 2019Landmark United in Science report informs Climate Action Summit
From The Financial Times: "The limits of the pursuit of profit"
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One Planet Only Forever at 03:15 AM on 6 October 2019Landmark United in Science report informs Climate Action Summit
This comprehensive and robust report improves awareness and understanding. And improving awareness and understanding should reduce anxiety and fear.
But the way people have been winning competitions for status based on perceptions of popularity and profitability has unsustainably developed incorrect and harmful beliefs and actions. The result is that this increased awareness and understanding actually increases anxiety and fear.
This long comment is presented to establish context for a critical response to suggestions that the pursuit of profit can and will be “The solution” to the climate impact problem.
For a long time, like many others, I have pursued increased awareness and understanding of what is required for humanity to develop a sustainable and sustainably improving future. I have learned that sustainable development requires anxiety and fear to be reduced. And improved awareness and understanding is the only way to sustainably reduce anxiety and fear.
However, because of the incorrect direction of development, particularly during the past 30 years, this report increases anxiety and fear. It increases justified anxiety and fear by showing how much worse the current situation is than it needed to be, with the related understanding that the required corrections are still being successfully harmfully resisted (justified fear expressed by the likes of Greta Thunberg).
A more important understanding is that the improving awareness and understanding increases anxiety and fear in people who have developed beliefs that are not supported by the improving awareness and understanding, particularly if those unsustainable beliefs are used to defend developed interests to personally benefit from unsustainable and harmful activities. That increased fear is regarding how much the required correction will cost people who have overdeveloped their beliefs and actions in an incorrect and unsustainable direction.
That understanding leads to an awareness and understanding that many, but not all, influential “winners and wanna-be-winners” unethically make-up and promote misleading stories. They do it to get as many people as possible to continue to be supporters of resisting the corrections of understanding that are required for humanity to develop a sustainable and sustainably improving future. They do it out of fear of personal loss.
That fearful resistance has developed in a variety of socioeconomic-political systems and related to many matters, not just climate impacts. But it has powerfully developed in democratic consumerism based systems, most notably in systems that have not developed effective governance ruled by the pursuit of “Development of Sustainable Improvements, Helpfulness to Others”.
Marketing science has improved the understanding of how people think and behave in response to marketing. Regrettably, driven by pursuits of winning in politics and consumerism, it has developed the understanding that misleading people into being anxious and fearful can be beneficial when it is done 'to help people resist the corrections that would be required by improved awareness and understanding'.
It is obvious that through the past 30 years "the profit motive" has failed to be helpful to the future of humanity, particularly because of the freedom to develop and deliver misleading marketing without a significant personal consequence. Through the past 30 years many of those among the population who are wealthier - the people that the likes of Adam Smith and John Stuart Mill believed would end up governing helpfully because of their higher level of awareness and understanding - have acted harmfully contrary to improving awareness and understanding and its application to develop sustainable improvements for humanity.
The "pursuit of profit" is not the problem. The lack of Caring Helpful governance in pursuit of, and improvement of, the Sustainable Development Goals is the problem. The problem is the way that pursuit of popularity and profit can over-power the governance of any system, especially a system that encourages more freedom for people to "believe and do as they please".
SkS, and many other initiatives, have been developed to try to help improve awareness and understanding. SkS is focused on the Climate Action goal. But all of the SDGs face similar unwarranted resistance to being achieved and improved on.
Only time will tell how bad things will become before anxiety and fear is sustainably reduced to the point where undeserving promoters of unjustified anxiety and fear will fail to significantly influence what is going on.
Hopefully the future of humanity will not suffer too much harm from the 'pursuits of popularity and profit' before current day leadership dedicates its efforts to improving awareness and understanding in pursuit of sustainable improvements for the benefit of the future of humanity (learning from people who are dedicated pursuers of improved awareness and understanding and leading on that basis rather than unethically prolonging unsustainable popularity or profitability).
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MA Rodger at 21:21 PM on 5 October 2019It's not us
richieb1234 @110,
The reflectiveness of cloud is the method by which SO2 provides climate forcing, this by providing aerosols to make the forming clouds shinier. But there is much complication. SO2 is not the only aerosol agent and such mechanisms are short-lived and local. Thus, say, SO2 emissions causing shiny clouds at high latitudes, especially during winter with long nights, will not have as much sunlight to reflect. And the longevity/altitude of the aerosol will differ by location.
The resulting cooling will be less localised.
And globally there is an unresolved issue here. The reductions in SO2 emissions which will follow from eliminating FF use and the resulting loss of its negative climate forcing has got some to worry that there will be a boost to AGW as we de-carbon our economies. Some work is saying this is not really much of a concern (eg Shindell & Smith 2019 [Abstract]) while on the other side of the debate we find Cowern (2018) who argues that such a boost is already happening and the strong warming in recent years is due to the reducing SO2 emissions.
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nigelj at 06:29 AM on 5 October 2019Landmark United in Science report informs Climate Action Summit
Fermin Francisco @1
The profit motive is indeed a useful tool. We see this because wind power is now so economically attractive it makes a profit - assuming you are replacing old worn out coal fired plant for example.
However there is no real profit in replacing more recently built coal fired plant with renewables, and planting forests, carbon capture and storage etc, unless the government subsidises these things, or alternatively a carbon tax penalises continued use of fossil fuels. Remember those forests need to remain unused for decades, they cannot be sold for profit as such.
So the climate problem is a political problem, where your lobbying efforts are probably better directed mainly at governments.
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BaerbelW at 04:18 AM on 5 October 2019Climate denier scientists think these 5 arguments will persuade EU and UN leaders
Alex Maycock tweeted about the background of the „ambassadors“ for the letter. Here is the link to list of tweets via the thread reader app:
https://threadreaderapp.com/thread/1180130582061125633.html
Climate Feedback also reviewed the letter and gave it an overall rating of very low:
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richieb1234 at 22:03 PM on 4 October 2019It's not us
MA Rodger
Thanks for the response. I will look into the IPCC and NASA references.
"The graphic on this webpage suggests 30% reduction 1980-2010 and other data suggests reductions do continue but less strongly."
Yes. If anything, particulate concentrations may rise for the rest of the century. The graphic shows a very small contribution from Africa. U.N. Population projections for Africa show 4 billion people by the end of this century, comparable to Asia. That could ramp up worldwide average particulate concentrations and spread them more equally across the globe. Qualitatively, the competition between GHG warming and particulate cooling could be the biggest uncertainty in the future.
"One reason that this may be so is that aerosols are very short lived and thus their effects dependent on the region of their emissions"
I see your point, but wouldn't the total amount of solar reflection be the most important variable, no matter where it occurs? Wouldn't the resulting cooling eventually even out across the globe? I will take your suggestion and look at the IPCC reference. --Richieb
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Fermin Francisco at 18:28 PM on 4 October 2019Landmark United in Science report informs Climate Action Summit
Urgent world-scale action has long been needed to address climate change, and the most effective tool to use is the profit motive. Here's the vision: 1st World green citizens in their millions persuade their contact companies to partner with 3rd World co-ops and companies starting with the Philippines as modeling country to set up high-profit green industries. Projects: Ethanol distilleries fed by sweet sorghum farms. Thousand-hectare agroforests with processing factories for export production. Geothermal plants. Mini-dam hydropower nets. Methane digesters and E85 engines for on-site power generation. E85 & electric transports. Low-cost solar cells. Forest resorts. All-electric metals industries. Agroforest water supply, toll roads, etc. Current billion-dollar Green Funds should finance the projects at 75% levels due to sure repayment plus interest income incident to the projects' high profitability. Spread out tropics wide, the projects should sequester atmospheric CO2 at billion-ton levels each year for all time, while employing millions of poor and creating huge markets for all involved companies. Details: https://fermin4greenearth.blogspot.com.
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MA Rodger at 06:50 AM on 4 October 2019It's not us
richieb1234 @106,
It is correct that there has been a substantial reduction on SO2 emissions over recent decades. The graphic on this webpage suggests 30% reduction 1980-2010 and other data suggests reductions do continue but less strongly. Yet when the aerosol forcing is shown (eg IPCC AR5 AII Table 1.2), we see a peak in 2000 and a very minor decline.
One reason that this may be so is that aerosols are very short lived and thus their effects dependent on the region of their emissions. NASA data (since 2005) allows the latitude of emissions to be easily quantified. Since 2005 thre have been small reductions in higher northern latitudes (eg USA & Europe), quite large reductions in lower northern latitudes (eg China) while emissions in the tropics and the southern latitudes have remained roughly constant. I would suggest that there is little relationship between global totals for SO2 emissions and the global size of the resulting climate forcing. The location of the emissions has a big effect on the overall forcing levels.
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nigelj at 08:47 AM on 3 October 20192019 SkS Weekly Climate Change & Global Warming News Roundup #39
The death of science in America: The silenced: Meet the climate whistleblowers muzzled by Donald Trump
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scaddenp at 06:55 AM on 3 October 2019It's not us
richieb124 - the IPCC reports each have a chapter on attribution which is what the literature calls it. I agree that your analogy is a good one but doing real-world attribution is a very complex task. The "fingerprints" in this post I think is about as good as it gets without using a physics-based model. Each individual one is ambiguous, but the sum is telling.
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richieb1234 at 22:07 PM on 2 October 2019It's not us
:As I mentioned earlier, I am a trainer. As I read and reread the original post, I think a good analogy to use is the way in which police organizations identify the source of an illicit drug. A drug that's intercepted on the street could come from anywhere: Colombia, Bangladesh, a rooftop in New York. "You just can't tell for sure." But international law enforcement agencies have developed the forensic methods to identify the source by examining its physical and chemical signatures. It works for natural and synthetic drugs. One can even identify where drugs have been "cut" by the signatures of the chemicals used. The same approach is used to distinguish natural causes of warming from man-made causes. I think this is a good analogy that most adults can identify with. Once they understand the approach, their minds will be much more open to hearing about the 10 signatures of anthropogenic warming.
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richieb1234 at 21:26 PM on 2 October 2019It's not us
David Kirtley: I did get into the Bloomberg link using Google. Very intereting. But I was surprised that it shows a negative trend on temperature effect of aerosols all the way to 2005. The information I have shows worldwide aerosol concentrations dropping by about 30% between 1980 and 2010. Shouldn't that have caused somewhat of a reversal in the temperature contribution?
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nigelj at 18:16 PM on 2 October 20192019 SkS Weekly Climate Change & Global Warming News Roundup #39
This video by Sir David King is well worth a look on a history of the science, and some interesting and novel mitigation ideas : New Tools for Climate Repair...
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It's not us
richieb1234 - As MA Roger pointed out, volcanic activity adds complexity to any kind of curve-fitting. Climate response to volcanic aerosols is quite fast compared to other forcings.
Tamino did an excellent article on using a combination of a simple 2-box model (one fast response, one slow) along with ENSO, and and showed an excellent fit to the observed climate response, see Once is not enough. Two time constants (2 and 26 years) and one large oscillation appear to be sufficient parameters to map the climate response to forcings.
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scaddenp at 06:47 AM on 2 October 2019It's not us
For a purely empirical fit of ENSO, Volcano, solar to temps since 1950, try here. Unlike other curve-fitting exercises which try to show warming is due orbit of jupiter, rise of irrigation etc, this uses half the data as training set and then uses the result to model the other half.
Benestad & Schmidt 2009 challenged Scafetta nonsense with naive empirical analysis of effects of forcing which I think may be closer to what you want.
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william5331 at 04:57 AM on 2 October 2019Ice sheet melting: it’s not just about sea level rise
Just wondering. What percent of deep water formation is caused by the freezing of surface water on the surface of the Arctic and Antarctic oceans with the accompaning creation of brine. The amount of ice formed each year in the Arctic has remained more or less constant over the years as reduced ice cover allows more heat to be vented to the atmosphere due to the lack of an overlying insullating cover of ice.
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MA Rodger at 03:09 AM on 2 October 2019It's not us
The Bloomsberg link is not to an "article" as such but to a set of graphs beneath which is set out the methodology behind the graphs. And within that methodology is a link to what could be construed as the underlying "article" - Miller et al (2014) 'CMIP5 historical simulations (1850–2012) with GISS ModelE2' although it has broader coverage.
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David Kirtley at 02:46 AM on 2 October 2019It's not us
Hmmm...that's odd. The link works for me. Maybe try google?
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richieb1234 at 00:00 AM on 2 October 2019It's not us
David Kirtley and MA Rodger
Thank you both for the responses. David, the Bloomberg link did not get me to the article, and neither did their search option. Do you happen to have a copy?
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MA Rodger at 22:48 PM on 1 October 2019It's not us
richieb1234 @98,
The basic problem you face trying to simply show a tight correlation between forcing & temperature is the impact of large short-term changes in climate forcing caused by volcanoes superimposed on the slower changes in climate forcing, as shown here in IPCC AR5 Fig 8-18. (The numbers are available in AR5 AII table 1.2.)
Because of these more dynamic changes, I have found the task involves far more than forcing and sensitivity. Even using a simple Climate Response Function (the timed progression of a warming resulting from a forcing based on the sensitivity - see for instance Hansen et al (2011) who discuss these at some length.) doesn't overcome the problem. You would end up having to set up what is undeniably a model to convert forcing into the resulting global temperature change. (I would add here that in 1910 the climate system was far from in-balance and so 1910 is not a good date to begin such modelling.) And for such a model not to be actually emprirically-based, you would probably end up with a full GCM model whose credibility has, as you say, been criticised by climate denialists.
This is what is being shown in the link @99. But I would ask if you need the modelling to present the message that the climate forcing of recent times forcing is overwhelmingly anthropogenic with the only significant effect from natural forcing being those short-term volcanic forcings. If the forcings are overwhelmingly anthropogenic, it is surely difficult to argue that it is not the same for the warming.
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David Kirtley at 22:12 PM on 1 October 2019It's not us
richieb1234--Bloomberg Businessweek (of all places!) had a really good look at this a few years ago: What's Really Warming the World which is based on NASA-GISS modelling.
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richieb1234 at 18:19 PM on 1 October 2019It's not us
I am engaged in developing and delivering training courses on AGW to teens and senior citizens in the Washington D.C. area. I find useful text and graphics in all three levels (basic, intermediate and advanced) of this post. Great job!
What would be good is a credible and scrutable discussion and graphic presentation of how the various forcing factors affected the global temperature since 1910; i.e. the steady increase from 1910 to 1940, followed by the slight downward trend from 1940 to 1975, followed by the sharp increase from 1975 to the present. Citing model calculations is useful, but skeptics have done a good job of casting doubt on the credibility of models, and models sound like black-box mumbo-jumbo to a non-technical audience.
A more understandable story emerges if you just examine the trends in sunlight, GHGs and aerosols and relate them to the shape of the curve. Your post does some of that, and I plan to use the insights from it. In addition, I have looked at the graphs of trends in GHGs, aerosols and sunlight since 1910, and I can tell a pretty good qualitative story. But has anyone done a simple quantitative analysis to try and reproduce the shape of the temperature curve?
From the reading I have done, there appears to be some good analysis of the sensitivities of global temperature to changes in GHGs, aerosols and incident sunlight. Has anyone with access to all the basic data simply multiplied the sensitivity times the amount of change for each of these factors and summed them up for each year since 1910? Would an analysis like that produce something that looks even vaguely like the temperature curve? Is it necessary to include other factors? Or is it a futile exercise?
Thanks for the great work you are doing to keep this issue in front of the public.
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One Planet Only Forever at 13:58 PM on 1 October 2019Welcome to Skeptical Science
TungstenX,
As you read the CBC article I refered to, pay attention to the mentions of John Cook, the same John Cook who authored this "Welcome to Skeptical Science".
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One Planet Only Forever at 12:52 PM on 1 October 2019Welcome to Skeptical Science
TungstenX@63
I offer the following points to supplement the responses from Eclectic and KR:
- In Eclectic's@62 list of groups I would add a group between B and C. This group likes to benefit from fossil fuels more than they care about understanding how harmful it is for them to benefit that way. That makes them like the A and B, but they are not super rich because of it or paid by the super rich to create misleading marketing for their benefit. I personally believe this is the largest group. And they are obviously easy to impress with misleading marketing. And they are propaganda foot-soldiers, readily repeating the nonsense they like.
- The CBC News website article "How 'organized climate change denial' shapes public opinion on global warming" may help you understand why there are still so many deniers and delayers regarding climate science (because of the required corrections of developed popular and profitable activities that it has exposed).
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Eclectic at 09:42 AM on 1 October 2019Welcome to Skeptical Science
TungstenX @63 ,
Margaret Thatcher was very much an economic conservative, and pushed for privatisation of Britain's coal mines in the early 1980's. Hence her big clash with the unions 1984/85 ~ where she was victorious. Over the next decade or two, most of the mines closed (being uneconomic) . . . and Northern England became an older version of West Virginia, as Americans might say. So Thatcher was rather "the opposite" in coal policy, compared with a more recent US President's ideas.
Thatcher's passionate interest in environmental conservatism (her major speeches to world leaders in 1988/89) seems to have developed subsequent to her coal-mining victory. So no, I'd have to disagree with the suggestion of her using the AGW/environmental concerns as a lever against the coal miners' union.
Thatcher had a Bachelor of Science degree in chemistry (according to Wiki, she was the first British Prime Minister to have a science degree) ~ so she was no novice or dummy in matters of science. And her strong advocacy for world action against climate change, is apparently completely genuine (just as it should be, for a true conservative).
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nigelj at 08:28 AM on 1 October 2019Ice sheet melting: it’s not just about sea level rise
Interesting coincidence: Massive iceberg breaks off Antarctic ice sheet
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