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SirCharles at 07:32 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
"Alarmists"?
A new study based on evidence from past warm periods suggests global warming may be double what is forecast.
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Evan at 06:54 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
I was not aware that Hansen had walked back this statement, so appreciate the correction Michael and Daniel. Still, we are talking semantics, whether we trigger runaway greenhouse effects or just cause mass extinction due to one of the other major effects of global warming. So even if such acclaimed scientists have walked back their most dire forecasts, it is notable that they made them at all, because both of these men are (were) great thinkers and scientists.
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nigelj at 06:48 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
I would clarify that I mean 2 metres of sea level rise by 2100. We know considerably more is locked in longer term as well, but this century is particularly important because of all the existing infrastructure.
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nigelj at 06:44 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
Steven Hawking probably knew his days were numbered, and wanted to give humanity a warning about climate change, something I find pretty admirable. He was unable to converse at length, so chose a few hard hitting words. His scenario is however incredibly unlikely.
The IPCC reports are so conservative its ridiculous, and they are so nuanced and complex the big serious issues become lost from the publics perspective.
But if you bring forwards very unlikely and extremely scary scenarios like Hansens or Hawking, it can possibly have the reverse effect of whats intended.
I think more attention needs to be paid to sea level rise scanarios like 2 metres, and dangerous but plausible biosphere issues, because all these can be defended as plausible with some decent evidence. Imho this is the sort of thing the climate community needs to unite behind.
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Daniel Bailey at 05:37 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
Evan, in his Exaggerations paper, Hansen walked back from a Venus-style runaway for the Earth, but readily maintains that we can still make the biosphere inhospitable to civilization as we currently enjoy it.
"With the more realistic physics in the Russell model the runaway water vapor feedback that exists with idealized concepts does not occur. However, the high climate sensitivity has implications for the habitability of the planet, should all fossil fuels actually be burned.
Furthermore, we show that the calculated climate sensitivity is consistent with global temperature and CO2 amounts that are estimated to have existed at earlier times in Earth's history when the planet was ice-free.
One implication is that if we should "succeed" in digging up and burning all fossil fuels, some parts of the planet would become literally uninhabitable, with some time in the year having wet bulb temperature exceeding 35°C.
At such temperatures, for reasons of physiology and physics, humans cannot survive, because even under ideal conditions of rest and ventilation, it is physically impossible for the environment to carry away the 100 W of metabolic heat that a human body generates when it is at rest. Thus even a person lying quietly naked in hurricane force winds would be unable to survive.
Temperatures even several degrees below this extreme limit would be sufficient to make a region practically uninhabitable for living and working.
The picture that emerges for Earth sometime in the distant future, if we should dig up and burn every fossil fuel, is thus consistent with that depicted in "Storms" — an ice-free Antarctica and a desolate planet without human inhabitants"
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michael sweet at 05:35 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
Evan:
According to Mashable:
"Hansen himself corrected his theory later on, writing that Venus-like conditions in the sense of 90 bar surface pressure and surface temperature of several hundred degrees "are only plausible on billion-year time scales"
GOOGLE says many scientists came out and said that Hawking was incorrect when he made his statement. This never happens with denier statements. In addition, Hawking is not a climate scientist.
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Evan at 03:24 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
How about these alarmist, extreme views? Does the time scale matter?
"We are close to the tipping point, where global warming becomes irreversible. Trump's action could push the Earth over the brink, to become like Venus, with a temperature of 250 degrees [Celsius], and raining sulfuric acid." Stephen Hawking
"[I]f we burn all reserves of oil, gas, and coal, there is a substantial chance we will initiate the runaway greenhouse. If we also burn the tar sands and tar shale, I believe the Venus syndrome is a dead certainty." James Hansen
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sauerj at 02:56 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
The only site that I have seen that I would call 100% bonkers alarmism is arctic-news.blogspot.com/. Their home page claim that temps will be +10.02C by 2026 is nothing but ridiculous, non-science lunacy (I love the "0.02" precision of their number). Their claim is so outlandish, that part of me thinks that they are really a cover group for the larger, open denialist groups. Once 2026 comes, and we are in the range of ~1.1-1.3C (running average), then this cover group's real ploy will then have reached its full tactical intent, giving the denialist establishment a gift to show how "stupid all the climate change nuts are out there".
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rocketeer at 02:29 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
The term "Climate Alarmist" is not mutually exclusive form "Climate Science Denier". Search 'Grand Solar Minimum' on youtube and you will find many videos excplicitly rejecting AGW yet warning of impending doom (crop failures, food shortages, starvation) as soon as this year due to the GSM which they are certain is already underway. They are now attributing every natural event from droughts to volcanoes to earthquakes to a solar variation that is still well within the range of behavior over the last century. It is hard to call this anything but alarmist. Compared to these baseless warnings, a calculation that Florida could be submergeed in a few hunded years sounds pretty sober and contemplative.
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michael sweet at 02:12 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
Johnboy,
It is impossible to make the deniers happy. We just had the 30th aniversity of Hansen's senate testimony. His projections have proven to be extraordinairly accurate and the deniers loudly claim that he was alarmist.
The graph of expert opinion versus what is discussed in the media (in the OP) shows that realistic evaluations of future problems is not accepted. Those considered "alarmist" are scientists at the high end of what is possible. Only the low end of possible is allowed to be discussed.
Only 10 years ago deniers used the term "catastrophic" global warming (CAGW) to insult the IPCC and scientists in general. Scientists never used that term because it was "alarmist". Today it is common for scientists to state that problems like drought, sea level rise, increased storms and flooding are potentially catastrophic. What was considered "alarmist" 10 years ago is now the mainstream opinion.
Your suggestion of muzzling scientists who you consider "alarmist" would just shift the discussion even more to the denier side than it is already.
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michael sweet at 01:58 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
15 years ago James Hansen was called an alarmist because he claimed it was possible (not likely, only possible) for there to be 5 meters sea level rise by 2100 when the IPCC was estimating something like 0.3 meters.
Now high sea level is commonly estimated as 2 meters and a significant number (not a consensus) of top scientists agree that 5 meters is possible. Hansen's 5 meters no longer can be called "alarmist", it is just a high end estimate. The IPCC estimate from 1990 is clearly wrong (much to minimalist) and was incorrect even when it was published.
The same holds true for estimates of the disappearance of Arctic sea ice. 15 years ago they estimated 2100 before the ice was gone and now 2030 is a more common estimate. The OP states "Peter Wadhams predicted in 2012 that the Arctic would be ice-free in the summer by 2016" which is incorrect. Waldhams predicted ice free conditions in 2016 +/- 3 years. That includes 2019 which has not yet passed where I live. If next year has melting conditions like 2007 with the current thin ice Waldhams could still be correct.
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Johnboy at 01:48 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
For the general public, I believe it is important to address the alarmists'misinformation as it is for the denialists'. Alarmist claims and predictions aren't being ignored. The denialists get a lot of traction consistently reminding the public of exaggerated claims and predictions. It's a great tool for the denialists, with no scientific arguments, to trash the notion of human caused climate change.
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Evan at 00:52 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
To add to what jef@8 said, one would hardly call Prof. Richard Alley an alarmist. Yet Prof. Alley himself said that early in his research career they did not publish their actual findings on how rapidly the climate can shift from one state to another (watch here) because they could not believe that the climate could switch from one state to another in a matter of years. It took he and his colleagues some time to get comfortable with the concept that there are "Dragons" out there, that could cause rapid changes in climate. So we cannot be sure of anything except that pushing the climate as hard as we are will not have a happy ending. All that we are discussing is whether it takes years, decades, or until the end of this century.
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jef12506 at 00:42 AM on 11 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
"It’s quite safe to say we won’t go extinct in the next few decades."
About the most UNscientific deduction I have ever heard. Its like saying;
"I woke up this morning and I'm not dead therefor it is safe to say I will not die for years"
Mcphersons scenario is plausable if not immediately so. That alone should alarm everyone on the planet to the extreme.
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Evan at 23:50 PM on 10 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
I often watch talks by Kevin Anderson and Clive Hamilton, who has been heavily influenced by Kevin Anderson. The conclusions of their research is alarming, and the lack of response of the world to this crisis is equally alarming, even if it can be explained as the way humans deny what they don't want to believe.
I don't mind replacing "alarmism" with a new word, but it too will then become overused and annoying. It is trully alarming what is happening and what we are not doing to address it.
Despite the statistics that claim more than 50% of people believe in human-caused global warming, I don't personally know of a single person (other than my wife) who has made meaningful changes to their life to address this crisis.
To me that is alarming.
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agno at 21:32 PM on 10 July 20182018 SkS Weekly Climate Change & Global Warming Digest #27
Coitus Cibus Interruptus
If an energy utility had enough self control, wood pellets could be pyrolysed, rather than fully burned, utilizing the volatile hydrocarbons for fuel and sequestering the remaining charcoal (biochar).
This arrests the cycling of sawdust back into the atmosphere; provides an energy source from a waste product; has the potential to improve soil fertility, and therefore accelerate reforestation/afforestation; and could attract carbon credits - given the long soil residence time of biochar.
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Eclectic at 17:11 PM on 10 July 2018CO2 lags temperature
Tcflood @574 ,
if I am understanding Dana's point correctly, he means that the land surface (most land being in the NH) warmed faster than the ocean. This affected glacial ice, to melt and discharge fresh water into the northern Atlantic Ocean. The Atlantic Meridional Overturning Circulation was disrupted by the "flood" of fresh water, and impeded/handicapped the north Atlantic warming — allowing time for the Southern Ocean's warming to leapfrog ahead of the northern oceans (including, presumably, the north Pacific Ocean).
The Southern Ocean's warming being the major source of CO2 release (as oceanic CO2 solubility reduces) . . . fits in with the ~1000 year "lag" in the warming/CO2-rise relationship. Remembering that the initial small warming from Milankovitch orbital effect does trigger the much larger planetary warming from CO2.
So no actual discordance between the comments at SkS and RealClimate.
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MA Rodger at 17:07 PM on 10 July 2018Increasing CO2 has little to no effect
jesscars @355,
The Ice Age cycles are strange beasts. They are triggered by changes in the solar warming of the Northern Hemisphere (the Milankovitch Cycles) but the climate has to be primed and in an a-stable state for the trigger to work.
And while the trigger is quite a gentle shove to climate, the triggered 'impacts' are big enough to raise global temperatures some 5ºC. The 'impacts' are technically feedbacks forced by the Milankovitch Cycles but it is these feedbacks that do all the work.
Simplistically, the main instability is the polar Ice Age ice caps that begin to melt out, this raising temperatures and destabalising further ice caps. And on the back of this warming, the level of atmospheric CO2 and CH4 will rise.
In the case of CO2, the carbon cycle requires oceans and biosphere to be in equilibrium with the atmosphere. With warming ocean waters, less CO2 can be carried by the warmer water, raising atmospheric CO2 levels which in-turn adds to the warming process. And the frozen biosphere also releases captured CO2 as it melts. (These processes will be at work today under AGW but with only 1ºC of warming in less than a century, the impact of the warming CO2 feedbacks is much less than the 100ppm CO2 Ice Age effect that resulted from much more warming over 8,000 years.) In very simple terms, that answers "Why does CO2 change over time i.e. where does it come from, where does it go?" Volcanoes do emit CO2 but it is only very exceptionally (within the billion year planet's history) that volcanism has elevated atmospheric CO2 by anything of significance.
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tcflood at 15:25 PM on 10 July 2018CO2 lags temperature
Above in the third listed point of the intermediate explanation, the statement is made “The Southern Hemisphere and its oceans warmed first, starting about 18,000 years ago.”
In a posting on RealClimate at http://www.realclimate.org/index.php/archives/2017/07/climate-sensitivity-estimates-and-corrections/ , Gavin Schmidt discusses methods of getting climate sensitivities from paleoclimatic data. He says that “Others have identified the lags in the southern ocean (which warms more slowly than the northern hemisphere, and northern land in particular) as the source of this time dependence of feedbacks, …” and so on.
Can someone please explain this difference in claim as to which hemisphere warmed first, or am I somehow asking the wrong question?
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scaddenp at 13:59 PM on 10 July 2018Increasing CO2 has little to no effect
jesscars - I have responded on a more appropriate thread here. Any discussion of past climate should go there.
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scaddenp at 13:58 PM on 10 July 2018Climate's changed before
Responding to jesscars from here:
Sigh, "OK, so you are saying that the effect of CO2 on the temperature is only minor. "
No, he was saying the CO2 direct contribution to ice ages is 0.5C. Mostly it is an amplifier (feedback) converting a change in northern NH albedo into global event.
Historically CO2 can change for many reasons, depending on which events you are talking about. Volcanoes, change to sea temperature (CO2 solubility), changes to vegatation cover, long term carbon sequestration in rock, freeze/thaw of tundra swamps, operating on time periods of seasons to eons. The pliestocene ice-age cycle is driven by milankovich.
Climate is always a response to sum of all forcings. (solar input, albedo, aerosols, GHGs). Past climates are considered by looking at what changes to all of them. Complicating matters is that temperature change triggers feedbacks - you cant change temperature without also changing CO2, CH4, water vapour and albedo.
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Eclectic at 13:45 PM on 10 July 2018Increasing CO2 has little to no effect
Jesscars, I rather suspect you have been pulling my leg with your story of your plastic bag experiments. Perhaps you just used that as an entry point for your argumentative disagreement with mainstream science.
As Scaddenp has said, you really need to educate yourself on basic science before you can seriously start to question things. Otherwise . . . you embarrass yourself with a Dunning-Kruger performance.
But fear not — there is time to redeem yourself. Why not try the intellectually-stimulating exercise of learning some genuine climate science from the articles, videos, etcetera found here at SkepticalScience & similar reputable sites. Or if you find your dour & angry mood persisting, then try the very entertaining Potholer54 video series I mentioned — all are amusing as well as informative about real science.
The more you learn, the more you understand reality. It is not a coincidence that all real scientists are in consensus agreement about AGW !!
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jesscars at 13:36 PM on 10 July 2018Increasing CO2 has little to no effect
Hi MA,
> jesscars @343,The relative strength of CO2 as a GHG is dependent on the logarithmic nature of its forcing. The first doubling will, molecule for molecule, be twice as 'forceful' as the second doubling and a thousand times more 'forceful' than the tenth doubling. So the 'forcefulness' you measure in the High-CO2 bag will be mainly a thousand-times weaker than the CO2 'forcefulness' involved in AGW. And while the ten doublings of CO2 together will provide a very 'forceful' GHG effect at 15 microns, (By-the-way, I note my 12 microns @340 is wrong - it is 15 microns.) this is achieved by stripping all GHG from everywhere else. This one-step-warmer-one-step-cooler effect for the bag world could well explain the non-result although there could be many other contributing reasons.
I agree with this. I repeated the experiment last night with about 2% CO2 or 20,000 or 5-6 doublings. (I.e. enough to get an effect from CO2 without diluting the effect of H2O.) The bag with CO2 was 0.5 degrees warmer during the night, outside. The difference disappeared in the morning.
> jesscars @347,Your comparison of the 1ºC of warming for double CO2 (without feedbacks) with the Vostok Ice Core temperature/CO2 graph doesn't properly hold. Firstly, the Vostok temperatures will be subject to polar amplification and Ice Ages result from other non-CO2 'forcings' (CH4, ice albedo) and their feedbacks. The direct CO2 contribution (without feedbacks) to the Ice Age cycles (which are globally some 5ºC) is probably something like 0.5ºC, which fits in with the logarithmic relationship. With feedbacks, the CO2 'forcing' is responsible for about a third of the Ice Age wobbles.
OK, so you are saying that the effect of CO2 on the temperature is only minor. If so, then what explains the correlation? Why would the other factors that contribute to temperature change move/fall at the same time as CO2? This is obviously not chance, so whatever affects the CO2 must also affect those other factors in order to get that correlation. Has this been proven by empirical research?
(Also, what is the cause of historic atmospheric CO2 change? I've heard several contradictory answers I.e. Milankovitch Effect or volcanoes. Why does CO2 change over time i.e. where does it come from, where does it go?)Moderator Response:[DB] Please confine comments to the focus of the thread on which you place them. Thousands of discussion threads exist at Skeptical Science; using the Search function in the Upper Left of every page can help you find them. Alternatively, you can click on the Arguments Tab to find different listings of topics (like a Taxonomic Listing or by Popularity). Area experts and knowledgeable individuals will respond to help you increase your understandings, but you must first be on-topic. Thanks!
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wili at 13:11 PM on 10 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
Sooo, if you see that there is a fire in a building full of people, and it looks possible or probable the the fire will spread rapidly possibly causing much death and injury...if you run to pull the fire alarm, you are by definition an alarmist, right?
Soooo, shouldn't we all be alarmists? Even the IPCC, which your own nice chart above shows is on the conservative side of accepted scientific opinion, shows really bad things coming down the pike toward us, certainly enough to be very alarmed about. And it is very likely that much of the IPCC is indeed to cautious and erring on the side of least drama.
Of course, we should all avoid making concrete predictions that particular events will occur on particular dates or years...the system is just too chaotic for those to be anything but intelligent (or not) guesses.
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scaddenp at 12:08 PM on 10 July 2018Increasing CO2 has little to no effect
Also, just to look at what you expect from your experiment, executed perfectly. Assuming you are around mid-latitude and in summer, that you use a jar of CO2 0.5m high, then changing concentration of CO2 from 100ppm to 20,000ppm should change flux from 414.8W/m2 to 415.4 if I have done calcs correctly. Not enough to change temperature by even 0.1C.
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scaddenp at 11:44 AM on 10 July 2018Increasing CO2 has little to no effect
jesscars - I explained why you cant do it with a plastic bag - it is not 55km high. You cant complain about science being wrong when the problem is with your understanding of it. You do not appear to have looked at resources posters have offered you.
You have now raised a whole bunch of long-debunked talking points which are offtopic here. Please use the search button on top left or the "arguments" to find the appropriate myth and comment there, not here.
eg "Climate has changed before", "Co2 lags temperature". It would seem that with a very large no. of misunderstandings about climate, that a read through the appropriate section the IPCC WG1 to get a grip on the basics. I would also reiterate the Science of Doom. Just for starters, the ice-age cycle is driven by orbital variation which primarily affect earths albedo. Once temperatures change, CO2 changes also from interactions with ocean and eurasian wetlands amplifying the effect. The detail here is huge - if you want to question the science, then please become familiar with the science first.
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jesscars at 11:38 AM on 10 July 2018Increasing CO2 has little to no effect
Hi Eclectic,
> (A) Firstly, there is the empirical evidence from experimentation during the past 150+ years, showing CO2 absorption of (some) Infra-Red radiation. (B) During the past century there is the empirical evidence of the CO2-related global Green House Effect [GHE] : evidence provided by both expensive and (relatively) cheap experimentations & observations. (Admittedly, "greenhouse" is a poorly-named term — but historically we are now stuck with it, and it is now a widely-understood useful label.)
Your experiment is inappropriate because of its lack of sensitivity and specificity (too many confounding variables in your experimental set-up).
Not only do you need to address the question of IR absorption by CO2 gas, but secondly you need to address the mechanism of the planetary GHE (a mechanism which is completely unconducive to backyard experimentation, I think).
What variables? You can't simply make a statement then not substantiate it.
I am aware of "evidence" of the planet warming or ocean levels rising or ice caps melting, but the climate has always changed naturally. Why assume it is being changed now by human-caused CO2? If you don't know the cause, measuring the effect doesn't prove anything. You really can't realy on any empirical measurements to prove AGW, you are left with the theory alone i.e. what happens when there is more CO2 in the atmosphere?
I have done the experiment several times. With different levels of CO2. The most I saw last night, at about 20,000 ppm, was an increase of 0.5 degrees. This is a CO2 doubling of over five times, so if this were in the atmosphere, it would be expected to increase by 5 degrees.
Why is it not possible to do an experiment in a plastic bag to measure a response?
I have been linked to similar experiments done to prove CO2 where they put CO2 in a fishtank, then shine a heat lamp. I pointed out that in nature, there is no heat lamp or artifiical source of radiation, so that experiment is not indicative of what will happen in reality. Why is it acceptable to do a fishtank + CO2 experiment to try to prove AGW, but not acceptable to do a plastic bag + CO2 experiment to try to disprove it? I'm happy to accept an explanation, but I don't see why, if you understand the reason, you can't simply explain it to me instead of send me to read hundreds of papers (unless you yourself do not understand it).
Can you also give an explanation - if the correlation shown between CO2 and temperature on the Vostok Ice Core samples is assumed to be causation, with CO2 causing temperature rise - why CO2 would have a linear effect on temperature (~1 degree per 10 ppm), but now we expect a logarithmic effect (i.e. 1 degree per doubling).
Can you explain what is going on with the molecular activity of the gas that would allow for such an unintuitive behaviour? Do all gases act this way when absorbing IR? Why? At what point do they go from linear to logarithmic and why? Has this been studied? It seems like it is fundamental to knowing whether climate science is accurate or not. How else can you come up with the prediction of 1 degree per doubling?
My understanding is that they act logarithmically, which would mean that the Vostok Ice Core samples can not be assumed to be that CO2 causes temperature. The 800 year lag, where temperature changes first also would support that. You know what does have a linear relationship though, and could explain the Vostok Ice Core samples? The CO2 solubility of water (oceans) between 0 to ~23 degrees.
Moderator Response:[DB] Please confine comments to the focus of the thread on which you place them. Thousands of discussion threads exist at Skeptical Science; using the Search function in the Upper Left of every page can help you find them. Alternatively, you can click on the Arguments Tab to find different listings of topics (like a Taxonomic Listing or by Popularity). Area experts and knowledgeable individuals will respond to help you increase your understandings, but you must first be on-topic. Thanks!
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Kiwiiano at 09:21 AM on 10 July 20182018 SkS Weekly Climate Change & Global Warming Digest #27
NigelJ: unless sawdust is buried deep underground in anaerobic conditions it's going to decompose into CO2 or methane eventually. Wood pellets are only neutral if they derive from plantation trees planted for production.
I've wondered if trees planted for sequestration of CO2 need to be buried too, but that would require machinery presumably requiring fossil CO2 release. It's quite tricky putting coal back in the hole.
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One Planet Only Forever at 08:16 AM on 10 July 20182018 SkS Weekly Climate Change & Global Warming News Roundup #27
nigelj@10,
Implied in my comment @11 is that it is not necessary to get acceptance from everyone. In fact, it is harmful to attempt to balance all interests.
Those who 'grow up mere children' need to be better educated. And should not be allowed to influence important decisions until they change their minds.
It would be (is undeniably) harmful to compromise the understanding of what needs to be done by balancing it with the developed desires of those who have 'grown up mere children, wanting to unjustifiably get away with what they would like to do - supposedly justified because it is popular or profitable or is not likely to result in legal penalty (because of secrecy, bad laws or bad law enforcement, or having sacrificial lambs to throw under the bus)'.
That is my engineer experience speaking. Some people will resist being better informed and more correctly understanding something. And they do not get to influence the important decisions I make. They end up being disappointed. And they deserve to be disappointed.
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One Planet Only Forever at 07:54 AM on 10 July 20182018 SkS Weekly Climate Change & Global Warming News Roundup #27
nigelj@10,
I would add the following items to your list:
- reduce the amount of energy consumption per person and maximize the percentage of the consumed energy that is sustainably sourced and delivered for consumption, with the richest being expected to lead by example toward the most sustainable lowest energy consumption ways of good enjoyable living.
- Achieve all of the Sustainable Development Goals, not just the Climate Action goal. This is actually Number 1, by a lot. It covers the other points and so much more. It may even be the only required point. Achieving this point would mean that many other corrections of what has developed, including ending the ability of undeserving competitors to win via misleading marketing campaigns, are effectively achieved (no more winners acting as they do because they can get away with it - to paraphrase a quote from "Our Common Future"). It would also mean a dramatic reduction of the number of people who "... grow up mere children, incapable of being acted on by rational consideration of distant motives ..." (a warning quoted from "On Liberty").
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nigelj at 07:32 AM on 10 July 20182018 SkS Weekly Climate Change & Global Warming News Roundup #27
OPOF @9,
I agree most people have some altruism in them. I think whats happened is society has lost faith in the egalitarian 1960's, and swung towards a more self centred economy since the 1980s economic reforms, and taken this too far. Imho the pendulum will swing back somewhere in the middle.
Ecomomists are already admitting the Thatcher and Reagon reforms had some problems. I think the challenge is to identify their good points, and the bad points, but having an intelligent debate on it seems elusive.
Regarding the 'Otter' article on discount rates. I found the link you posted obviously very good, but too technical for me so I hunted out a simplified version and thought it worth posting. It probably didn't go far enough on the philosophical issues we have to face.
I think the whole matter comes down to a value judgement, or ethical judgement if you prefer. For me it's namely "do we leave the planet in good working order for future generations, or not?" I use simple term like this that hopefully anyone can relate to .
Hopefully the answer is yes, and discount rates are part of figuring this out, but only go so far. We have to be asking what are the practical things this generation needs to do to give future generations a decent life? For me the main ones are:
1) Reduce carbon emissions
2) Reduce rates of population growth
3) Sustainable farming etc.
4) More careful and limited use of scarce resources, but without resorting to a 'sack cloth' lifestyle.
I dont see what else would make sense, or be likely to be acceptable to people.
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One Planet Only Forever at 07:32 AM on 10 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
I support the focus on correcting claims made by deniers of the developed, and continuing to be improved, climate science understanding; those who wish to claim that there is little need to change or correct the way things have developed.
As an engineer I encountered many people who promoted what they wanted as something that would be OK. But, ethically, I had to screen out the unethical/unsafe/likely harmful options, not let them even be considered, no matter how much quicker or cheaper they were. And I would try to avoid over-conservative options, because responsibly limiting the cost or time required to build something is an engineer's objective - but never compromise the ethical protection of the public, workers and environment from harm caused by what was being done.
And my MBA education in the 1980s included warnings about the unsustainable power of misleading marketing. Misleading marketing can be very effective at delaying increased understanding, which can increase the amount of undeserved benefit obtained from an activity.
My MBA education and work experience also exposed the way that business-minded people can consider 'risk management' to be identifying potential risks and making sure someone else will suffer the consequences if the potential risk actually occurs. The fact that climate change impacts primarily affect future generations, or affect other people who cannot negatively impact the people who benefit from creating the consequence, are a perfect 'Business Risk Mitigation' plan.
A different way to justify less effort spent on climate alarmist claims would be to present the case as a matter of ethically evaluating how important it is to address/rebut a claim. The ethical rule would be 'To increase the awareness and understanding of what is really going on and the application of that understanding to help develop a sustainable better future for humanity'. And the trigger for something needing to be addressed, and the urgency and magnitude of effort to address it, would be how Harmful (unethical) the claim is.
Some people may try to argue against that definition of the ethical rule, but that can lead to a very productive discussion as they try and fail to justify a different Good definition of Ethical. I think it is a very easy definition to defend. And it makes it difficult for a climate science denier to justify their desired beliefs as being worthy of consideration.
That ethical evaluation would clearly indicate that presentations of climate consequences that are possible, but more severe than what is currently considered most likely to occur, are not harmful and may be helpful. They are therefore not needing to be addressed.
Outside of the scope of climate science, the same evaluation would indicate that 'the alarmist claims about the (lost opportunity for/damage done to) a portion of today's population if the required aggressive reduction of climate change impacts was effectively pursued (forcing better behaviour and creating a loss of personal perceptions of superiority among the least deserving of the more fortunate)', are harmful unethical 'alarmist' claims that require serious rebuttal effort.
And Richard Betts would appear to be deserving of serious ethical rebutting.
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scaddenp at 07:12 AM on 10 July 2018Increasing CO2 has little to no effect
jessicars - when you do the experiment outside and you want to calculate the effect of your plastic bag of CO2, then you need to consider that column of gas under consideration is 55km tall and you have changed the CO2 content of the bottom few centimeters. Yes, that CO2 will trap IR radiation and re-radiate to the surface. Because that surface is receiving more radiation, it will heat up and the surface will heat the bag. You note that it is surface under that bag that is heated by back radiation, not the gas in bag. (hence thermometer under bag). The question is how much, and in your setup, yes, it is insignificant. To replicate the atmospheric GHE, you need a column of gas 55km or so high.
The experiments we pointed you to isolate other effects and applify the CO2 effect to make it measurable with thermometer. Radiation is radiation whether it is coming from heat lamp or a warm surface.
If you are looking for empirical evidence of GHE, then that paper on direct measurement is one, but see also our reference especially the CO2 traps heat section with papers from Harries, Evans, Griggs , Philpona, Chen who all compared the calculated radiation at either top of atmosphere or surface of earth and compared it to direct measurements.
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nigelj at 06:36 AM on 10 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
The term 'alarmist' is indeed an annoying dog whistle and smear campaign. Some people have labelled me an alarmist for simply saying climate change is serious, or for claiming its caused by human activities. Much gritting of teeth.
But climate change is alarming if you think of the long term consequnces. Perhaps the best retort is to tell people they should be alarmed, and then discuss the facts?
This website should list a few genuine alarmists, but it should just be people with extreme claims well outside the IPCC, that are not supported by the peer review literature. You dont want huge lists of alarmists, because this would be shooting yourself in your own feet.
A related example. Recently the Guardian wrote an article with claims sea level rise was doubling every seven years, and could reach 5 metres by 2100. The doubling claim was simply wrong, and only a couple of climate scientists claim sea level rise would be 5 metres by 2100. The Guradian should have said this.
These sorts of mistakes and unexplained claims make "warmists" look stupid and excessively alarmist, and provide the denialist community ammunition to make them look stupid. I did a google search, and a couple of denialist websites attacked the Guardian article. It all provides people "sitting on the fence" another reason to become sceptical of climate scientists. I agree with the article that these extreme fringe claims are not the main body of alarmism the denialists refer to, but it's still better not to have people making truly ridiculous claims.
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Sunspot at 04:37 AM on 10 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
I wish Mr. Betts would stop using the term "alarmist" over and over and over. It's a common dog-whistle term used by deniers. The article he cites supposedly debunking McPherson is over 4 years old. The basic argument seems to be that the bad things predicted by McPherson, Wadhams, and many others btw, haven't happened yet. We know that. So it's an argument over how fast methane can be released, how soon all the ice melts, etc. No mention of "global dimming". To say that the "alarmists" are wrong is a little premature. There is an impressive roster at the Arctic Blogspot site, not just two people as implied in this article. And I am convinced that a great many Climate Scientists are, privately, just as concerned as McPherson and Wadhams. This is why Arctic Blogspot uses the pseudonym "Sam Carana". Anyone being publicly "alarmist" may lose their jobs! Many Climate Scientists have left the US because they and their families receive death threats! But buy them a beer, and I'd bet they don't dismiss even the most dire predictions. We simply don't know what will happen, but the temperature increase is likely to be exponential, not linear. It's getting hot out there. All over.
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libertador at 03:53 AM on 10 July 20182018 SkS Weekly Climate Change & Global Warming News Roundup #27
Ted Franklin @5
One might be critical about the political wrongdoings with the story of the tragedy of the commons concerning common lands.
Besides, Hardin's proposal for pollution seems to be quite sensible and would be good if adapted in case of greenhouse gases. He proposes für pollution:
"But the air and waters surrounding us cannot readily be fenced, and so the tragedy of the commons as a cesspool must be prevented by different means, by coercive laws or taxing devices that make it cheaper for the polluter to treat his pollutants than to discharge them untreated." (The Tragedy of the Commons by Garrett Hardin, 1968, Science, 1968)
I hope some conservative thinktanks would think about this and adopt some of these policies.
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michael sweet at 03:06 AM on 10 July 20182018 SkS Weekly Climate Change & Global Warming Digest #27
I was reading Politico and saw a paid post from Exelon mentioning climate change. It had a picture of a nuclear reactor.
When I read the article I was pleasantly surprised to find it was an article in favor of a carbon fee. It mentioned that Exelon had nuclear plants but also mentioned hydro and renewable resources. It seemed to me that the article was pitched to conservatives as a solution to climate change.
I thought it was a good sign that a major electric utility would pitch a carbon fee to the general public.
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michael sweet at 02:55 AM on 10 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
Can Michael Tobias diagram of professional opinion be added to the SkS graphics page? I have wanted to cite it in the past but was not able to find it.
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ubrew12 at 02:11 AM on 10 July 2018There are genuine climate alarmists, but they're not in the same league as deniers
Its hard not to make alarmist appeals in arguments. For example, I've begun telling people that once we double CO2 (i.e. hit 560ppm), Earth will likely hit a 3C anomaly within 50 years (or around 2100). At 3C we'll be hotter than pre-industrial as the last ice age was colder. I then ask them to consider if countries would be economically impacted if they suddenly found themselves in the depths of the last ice age (according to this graph of the last 400,000 yrs of global temperature, ice ages run about 6F, or 3C, cooler than pre-industrial). If we'd find it difficult to run our countries in an ice age, why should we think 3C hotter than pre-industrial will be any easier?
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One Planet Only Forever at 00:30 AM on 10 July 20182018 SkS Weekly Climate Change & Global Warming Digest #27
Even without the potentially higher warming due to the already created increased CO2 levels, the lack of responsible leadership by the winners of competitions for power, popularity an profitability must be corrected if humanity is to have a future.
The current richest humans, particularly the ones who got rich because of the continued burning of fossil fuels since the 1970s when the harm being done was undeniable, need to be required to pay for the reduction of CO2 levels in the atmosphere.
Climate science is one the biggest examples of the many harmful threats, and actual producers of harm (not just the potential), that have developed because "winners" are not required to prove they have, and continue to, "behave the best".
People who are not interested in helping to achieve a sustainable better future for humanity, people who have developed personal interests that are contrary to achieving the Sustainable Development Goals, people who would lose developed perceptions of prosperity and superiority relative to others if the SDGs were aggressively pursued, Deserve To Be Losers.
The cries that the winners deserve their status and wealth, or that their personal perceptions of superiority must be maintained, need to be replaced with demands that the winners prove conclusively, through the ethical helpful truth of their history of actions, that they deserve the impression they have developed, that their image is not just an unsustainable unjustified disguise.
And that is the root of the problem - too many people are being allowed to grow up not caring about how their actions impact others, too many people do something beause they desire it and think they can get away with it.
Egoism (freedom to believe and do whatever you please) is inappropriately being allowed to over-power Altruism. Egoism's limits need to be understood to be Altruism. Examples: Gender Identity freedom is OK, Woman's choice to have an abortion is OK, carrying a gun in public is not OK, driving faster than the posted speed limit is not OK, driving after drinking alcohol is not OK, disliking and denying climate science is not OK, believing in a spiritual being is OK, using such a belief to deny or oppose climate science is not OK.
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Sunspot at 22:09 PM on 9 July 20182018 SkS Weekly Climate Change & Global Warming Digest #27
I'm in the camp that says it really doesn't matter anymore. There is already enough CO2 in the atmosphere to fry us, and the only reason we haven't yet is from global dimming, the fact that all the larger-particulate pollution reflects a lot of energy back into space. If/when that pollution disappears, either from well-meaning pollution controls or sudden economic collapse due to trade wars or shooting wars, the temps will skyrocket within weeks or days. This was proven post-911 when the planes were grounded.
I'm sure this group isn't popular around here, but I never see any good reasons for where they get it wrong. http://arctic-news.blogspot.com/ Yahoo won't even let me post this link anymore, even though they love links to Flat Earth and NASA "hoaxes", etc, Youtube videos.
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Eclectic at 21:42 PM on 9 July 2018Increasing CO2 has little to no effect
Jesscars — as an average reader here, I am puzzled why you persevere in trying to "fix" your backyard experiment set-up intended to replicate the already-demonstrated empirical evidence of CO2 "greenhouse".
(A) Firstly, there is the empirical evidence from experimentation during the past 150+ years, showing CO2 absorption of (some) Infra-Red radiation. (B) During the past century there is the empirical evidence of the CO2-related global Green House Effect [GHE] : evidence provided by both expensive and (relatively) cheap experimentations & observations. (Admittedly, "greenhouse" is a poorly-named term — but historically we are now stuck with it, and it is now a widely-understood useful label.)
Your experiment is inappropriate because of its lack of sensitivity and specificity (too many confounding variables in your experimental set-up).
Not only do you need to address the question of IR absorption by CO2 gas, but secondly you need to address the mechanism of the planetary GHE (a mechanism which is completely unconducive to backyard experimentation, I think).
And your later questions indicate that you have not grasped the essentials of global-scale surface temperature changes. Climate is a complex matter, and you must not expect to understand all the science of it, by means of a few paragraphs of explanations — You owe it to yourself to undertake basic self-education by extensive reading (and/or by some of the excellent video-tutorials available. And if you want to be entertained humorously by videos while self-educating, then seek out the series of Potholer54 videos — they educate indirectly, by amusingly debunking the numerous scientific errors committed by the anti-science brigade i.e. denialists. Potholer54 also does a series on evolution-deniers . . . but you probably won't have time for that sort of humorous entertainment sideline.)
The more you learn, the better you will be able to ask appropriate questions. Start from the basics, and then you can usefully re-visit Vostok and global warming response curves. As MA Rodger has implied, you have been trying to put the cart before the horse.
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MA Rodger at 20:56 PM on 9 July 2018Increasing CO2 has little to no effect
jesscars @343,
The relative strength of CO2 as a GHG is dependent on the logarithmic nature of its forcing. The first doubling will, molecule for molecule, be twice as 'forceful' as the second doubling and a thousand times more 'forceful' than the tenth doubling. So the 'forcefulness' you measure in the High-CO2 bag will be mainly a thousand-times weaker than the CO2 'forcefulness' involved in AGW. And while the ten doublings of CO2 together will provide a very 'forceful' GHG effect at 15 microns, (By-the-way, I note my 12 microns @340 is wrong - it is 15 microns.) this is achieved by stripping all GHG from everywhere else. This one-step-warmer-one-step-cooler effect for the bag world could well explain the non-result although there could be many other contributing reasons.
jesscars @347,
Your comparison of the 1ºC of warming for double CO2 (without feedbacks) with the Vostok Ice Core temperature/CO2 graph doesn't properly hold. Firstly, the Vostok temperatures will be subject to polar amplification and Ice Ages result from other non-CO2 'forcings' (CH4, ice albedo) and their feedbacks. The direct CO2 contribution (without feedbacks) to the Ice Age cycles (which are globally some 5ºC) is probably something like 0.5ºC, which fits in with the logarithmic relationship. With feedbacks, the CO2 'forcing' is responsible for about a third of the Ice Age wobbles.
The logarithmic nature of CO2 forcing holds certainly for 180ppm to 2,000ppm. (See for instance Etminan et al 2016.) At very low concentrations it will presumably be more linear (like CH4) but the point of change from logarithmic is not something I have met. Persumably the level is well below any CO2 levels ever seen on Earth.
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jesscars at 20:18 PM on 9 July 2018Increasing CO2 has little to no effect
Hi scaddenp,
My understanding is that CO2 molecules absorb terrestrial IR then reradiates it as heat. I'm not sure why it should matter if that's a bag with a higher concentration of CO2 or CO2 molecules in the atmosphere. I don't see why there should be a difference. Are you able to explain this to me? I will also check the papers.
OK, so you acknowledge that the warming, when under natural sources of radiation is insignificant. I understand that adding radiaton would increase temperatures, but the GHG of the atmosphere will only ever face natural sources so it doesn't represent what will ever actually happen.
I have tried the experiment at night, indoors, and outdoors, and with differnt concentrations of CO2. There is never a significant difference - definitley not 1 degree per doubling.
Also, can you please confirm the 1 degree per doubling and where this comes from? This is not matched on the Vostok Ice Core samples, which show a linear relationship of about 1 degree per 10 ppm. I am not sure why the discrepancy in the science.
Thanks,Jessica
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jesscars at 19:54 PM on 9 July 2018Increasing CO2 has little to no effect
Hi All,
I have another question re. temperature predictions.
If the expected warming is an increase of 1 degree per doubling of CO2, why is this not matched by the Vostok Ice Core samples? These show about a 1 degree per 10 ppm linear relationship.
Why would the historic linear trend be replaced by a logarithmic one? At what level of CO2 does this happen?Thanks,
Jessica -
TornadoWarning at 16:50 PM on 9 July 2018Water vapor is the most powerful greenhouse gas
After reviewing the comments posted by JeffDylan@267 regarding the rebuttals written by James Frank and John Cook to the concept of water vapor being the controlling greenhouse gas, I fail to see how JeffDylan misunderstood the explanation as indicated by moderator TD. In his rebuttal, Frank states (in the fourth paragraph)
"So even though water vapour is the greatest greenhouse gas, it is relatively short-lived."
and JeffDylan states (in the second paragraph of @267)
"... H2O vapor may be the strongest greenhouse gas, but it is much more "short-lived" in the atmosphere that [than] CO2."
It seems to me that these statements by James Frank and JeffDylan are exactly the same. So what is the misunderstanding?
The statement made by TD@267 that the residence times (or atmospheric lifetimes) of individual molecules are irrelevant is correct but in conflict with the rebuttals posted by both Frank and Cook and numerous peer-reviewed modern climate science articles. Many such articles can be found by doing a keyword search on "condensable greenhouse gases" as suggested by Eclectic@290. [Please note that I am supplying evidence for my claims from credible sources.] From these statements and articles, it appears that in modern "climate science", the radiative forcing strength of a greenhouse gas (GHG) is highly dependent upon the atmospheric lifetimes of the GHG modecules whereas in fundamental physics, the greenhouse effect associated with any GHG is totally independent of atmospheric lifetimes of its molecules. In other words, according to basic first-principles physics, the greenhouse effect of any gas depends only on its concentration, IR spectrum, and to some extent its location; and is the same whether the individual molecules recently emerged from a condensed state via CO2 greenhouse heating, or if they had been in the atmosphere since the formation of the earth. The terms forcing and feedback do not appear anywhere in the laws of physics governing the greenhouse effect.
From the alleged dependence of the radiative forcing strength of a GHG on molecular lifetimes, climate science arrived at the general "principle" that no condensable GHG could be a radiative forcing, no matter how strong of a GHG it is. This then becomes the justification for disregarding the possibility of a water vapor radiative forcing and considering only the CO2 greenhouse heating as the radiative forcing which controls temperature. If there is a rise in temperature as a result of more CO2 being added to the atmosphere (causing more greenhouse heating), then more water (or ice) will be evaporated into the atmosphere as a result of this temperature change. At this point, the new climate science says that since this additional water vapor was introduced as a feedback to the rise in temperature, its contribution to the greenhouse heating is not disregarded on the basis of short molecular atmospheric lifetimes. Instead, this feedback H2O greenhouse heating is what's asserted to amplify the CO2 greenhouse effect. The laws of physics, however, do not distinguish between forcing and feedback GHG molecules in the atmosphere.
This result is what's called the CO2 "control knob" effect. Even though H2O vapor is the stronger GHG, CO2 is still believed to control the greenhouse effect. We have shown, however, that this is merely a prediction, or should I say artifact, of our new "climate science". Other artifacts include bazarre, highly anti-intuitive frozen world scenerios if all of the CO2 were removed from the atmosphere. Unfortunately, such predictions generally seem to be regarded as new discoveries rather than contradictions resulting from faulty assumptions.
In summary, we have shown a great departure of the newly discovered climate science from the fundamental laws of physics. Not only that, but this "science" isn't even consistent within itself. It would be total folly to base important environmental decisions on this version of "climate science".
Moderator Response:[PS] Post currently embargoed pending sock-puppet investigation
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scaddenp at 14:36 PM on 9 July 2018Increasing CO2 has little to no effect
Why not?
Perhaps you should tell us how you think the GHE works? Check those references. An isothermal column will not have a GHE.
Any scientific experiment depends on controlling the variables in the experiment. As has been pointed out to you, your design has all sorts of issues with that. If you want to do this outside, then you need to do it at night really. The radiation that the CO2 is interacting with (IR) comes from heat re-radiating from the surface and that being re-radiated from GHG in the atmosphere all the way up. Not easy to control. Direct measurement of the GHE in the atmosphere is a complex experimental design, not for amateurs. See this paper for instance on how to really do it.
Using heat lamp as proxy for IR being irradiated surface allows you some control and at level which makes it measurable.
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jesscars at 13:48 PM on 9 July 2018Increasing CO2 has little to no effect
Hi scaddenp,
Thanks for the response.> 1/ what you are trying to do is demonstrating the radiative properties of CO2 which is central to the GHE, but you cannot demonstrate the GHE in a simple column of gas.
Why not? I am not sure why the warming effect of CO2 would not be seen in a local pocket of high-CO2 air.> 2/ Getting the experimental setup right is difficult as it is easy to overwhelm the CO2 radiative effect with other spurious influence. Have a look at this setup to make a better attempt.
Thanks for the comment. I have seen a similar experiment done on youtube, but my problem is that CO2 is what's being added to the atmosphere, there is no additional radiation other than what is there naturally. So using a heat lamp, unless it emulates only natural radiation variations does not a represent what will happen when CO2 is in the natural atmosphere. -
jesscars at 13:41 PM on 9 July 2018Increasing CO2 has little to no effect
Hi Bob,
Thanks for your response:> The air-filled bag would have water vapour in it - in whatever amount is present in the air at that time. (Probably at most a few percent.)
The CO2-filled bag would be dry - i.e. no water vapour.
As water vapour is also a greenhouse gas, the comparison is actually between two bags filled with different amounts of two different IR-absorbing gases. My first guess is that the CO2 would be a considerably greater IR absorber, due to its greater concentration, but You'd have to do the math. It does illustrate that there are a lot of fine details that need to be tracked.
H20 appears to be a more effective GHG by comparing at the infrared spectrums, here and here. The CO2 filled bag would have approx 1/4 the amount of normal air. I suppose I would have to do the maths, though I would have to know how effective the additional CO2 is and how effective the H2O is at creating heat. It does seem strange though that there is no real noticeable difference in the temperatures either indoors or outdoors or at night - it seems unlikely that these would always balance out. -
jesscars at 13:23 PM on 9 July 2018Increasing CO2 has little to no effect
Hi MA,
Thanks for the response.
> CO2's main absorption wave-length is at 12 microns. This is at the peak of the Earth's IR emissions but is an irrelevant part of sunlight. Thus a High-CO2 bag would be pretty-much transparent to sunlight as well as to the Earth's IR except at that 12 microns wavelength. This transperancy is because in the bag world, the CO2 has purged all the other GHGs and thus reducing the warming from those other GHGs. This one-step-forward-one-step-back doesn't happen under AGW. Indeed, a CO2-warmed world results in elevated water vapour, another GHG. AGW is operating day & night but the night-time temperatures will be boosted more than the day-time ones.
I can agree that the bag purges the other gases, so doesn't experience warming from those gases, but if they have a higher heat-producing capacity than the CO2 that replaces them, why would the net effect of adding more CO2 to air be to increase temperatures? I repeated the same experiment at night (indoors) and again, there was no notcieable difference in temperatures.
> The actions of CO2 as a GHG is not that of a simple insulation layer (although the circulations in the atmosphere are far less leaky than the leaks in any greenhouse). One (simplistic) mode of warming concerns the altitude at which the IR at 12 microns can get a clear-shot out into space. As more CO2 enters the atmosphere, the clear-shot altitude increases and the temperature at that clear-shot altitude drops. The lower the temperature, the less IR energy the clear-shot gases can shoot out into space. The bag world cannot demonstrate such AGW mechanisms.
I agree with this too, that if CO2 has a warming effect, the effects of CO2 in the bag do not represent what will happen in the atmosphere. But why wouldn't the bag show any warming at all? I don't see why adding more CO2 to the atmosphere should effect temperatures, but adding CO2 to the bag has no effect on temperature. If there is a global or atmospheric effect of adding CO2, why isn't there a local one (in the bag)?
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