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Comments 14151 to 14200:

14151. nigelj at 07:52 AM on 13 July 2018
       Rising ocean waters from global warming could cost trillions of dollars
       

       Sea level rise is likely to cause some very expensive problems to the worlds drainage systems, as water backflows up drainage systems

       During the Pliocene period temperatures were about 2-3 degrees warmer than currenty, and sea level was 25 metres higher than today over millenia time scales. The paleo climate record also contains periods of rapid sea level rise of several metres per century. We have to be very careful before we rule these out in todays world. Even a small possibility would be genuinely catastrophic on global scale, and must form the basis of risk analysis thinking.

       The Pliocene also had considerable regional variability of climate change, sometimes astonishingly severe change.

       As to economsists being "sceptical"of climate change projections, problems and costs. Ha ha ha, since when have economists ever understood anything, or predicted anything reliably? Large parts of macroeconomics are about as credible as voodoo.

14152. Bob Loblaw at 07:32 AM on 13 July 2018
       Book Review: A Global Warming Primer, by Jeffrey Bennett
       

       sauerj:

       The post (second-last paragraph) does include a link to a free on-line version of the book. Perhaps your questions regarding what it has to say can be answered by reading it?

14153. Bob Loblaw at 07:29 AM on 13 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       It is not reasonable to assume that just because one boy cried wolf, that every call of "wolf!" is unjustified. Rejecting a whole field of science because of one (or a few) "alarmists" overstated the risks requires a pre-existing desire to ignore the risk to begin with. That's not to say that large numbers of people won't respond that way.....

       ...but remember: in Aesop's fable, the wolf does eat the sheep in the end.

14154. scaddenp at 07:29 AM on 13 July 2018
       Animal agriculture and eating meat are the biggest causes of global warming
       

       Ben, interesting but this would be a lot more convincing if backed with some peer-reviewed science. Some of the sweeping statement "Without beef you can kiss goodbye probably to 50% of the earth's population" is pretty hard to support. This appears to be an extrapolation of NA farming practice (7.5% of world wheat production by FAO 2014) to rest of world. This isnt a farming practise here, and I suspect it also isnt the practice in major producers like EU,China,India, Russia.

       The question over water usage looks like a straw man. The water issues around cattle here focus on irrigation of pasture mostly. eg 1000 litres of water needed to produce 1 litre of milk. 15400 litres for 1kg of beef (eg see here). That is very high compared to plant-based protein sources.

       I do not contest the value of well-managed, low-input rangeland but at first glance your sources are unconvincing and smack of rhetoric.

14155. nigelj at 07:05 AM on 13 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       dkeierleber @31, I agree about Paul Ehrlich. These huge catastrophic claims are risky to make, because  if they dont eventuate they destroy the credibility of the entire environmental community and feed the denialists.

       Having said that, we dont want to muzzle scientists, like someone said above,  and sometimes the extreme alarmists are right. And Ehrlich  was right in principle, population growth is a huge problem.

       The book "Limits to Growth" made scarey predictions that didn't eventuate, but fortunately it stated these were based on known mineral reserves, and this reality would likely change over time. I think its important to "qualify your predictions", but then we have the huge problem that the media often dont report the qualifications.

       The IPCC sea level rise predictions just look too low to me. And you raise a good point they are global averages, and not regional, and theres no obvious warning in the IPCC documents that regional rates could be very high. If there is it gets lost in the fine print.

       Yes the antarctic destabilisation seems exaggerated in the "conservative direction" by the IPCC. Or perhaps put it this  way: they are right to say the probable trend is it will only add about 200mm to sea level rise, but they should have said theres a 'possibility' it could be much more, or that such things cant be ruled out.

       The paleo climate evidence suggests the Antarctic destabilied rapidly at one point causing 2 metres of sea level rise per century, although this may have been preceded by several years of a  developed warming trend of several degrees. But we just dont really know. The important thing is climate change has been rapid in the past, so I think we cant rule it out now. We dont know enough to be able to rule it out.

       However when I see estimates that sea level rise could be 5 metres by 2100 this stretches credibility. Past examples of this are rare and relate to periods when there was far more ice on the planet. So this is truly an extreme scenario and seems very unlikely to be relevant to our situation.

14156. dkeierleber at 02:55 AM on 13 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       I think all environmental organizations were damaged by the intentional alarmist predictions of Paul Ehrlich and others back in the 70s. So I think it is important to call out the few extremists and explain why mainstream scientists think they are wrong.

       SirCharles @21, I think the widely publicized news on this article is somewhat alarmist (though the paper isn’t).

       MA Rodger @23, Thanks for the link. I downloaded the pdf of the paper.
       I thought this subject was treated pretty well in the Ars Technica article https://arstechnica.com/science/2018/06/are-past-climates-telling-us-were-missing-something/ reposted on this site on June 28. https://www.skepticalscience.com/what-happened-last-time-as-warm-as-getting.html
       (Sorry, can’t get link tool to work. Are there instructions anywhere?)

       Nigelj @18 I think the conservative conclusions of AR5 have caused some damage. California communities are now looking at a realistic possibility of 6.5 ft of SLR by the end of the century while the Summary for Policy Makers had given a maximum of 0.98m. Granted a couple of 2015 papers were game changers in the area of SLR but the following comment from the SPM, in retrospect, seems exaggerated on the conservative end. “Based on current understanding, only the collapse of marine-based sectors of the Antarctic ice sheet, if initiated, could cause global mean sea level to rise substantially above the likely range during the 21st century. However, there is medium confidence that this additional contribution would not exceed several tenths of a meter of sea level rise during the 21st century.”

14157. Benjamin David Steele at 02:18 AM on 13 July 2018
       Animal agriculture and eating meat are the biggest causes of global warming
       

       Below are two passages quoted in Nourishing Traditions by Sally Fallon. The first is by Charles Hallmark from Health Freedom News:

       If it were not for beef, the United States could produce perhaps 25% of the small grain it does. . .. The factors that would limit our production is winter kill and tillering.

       First, winter kill happens when small grains, such as wheat or oats, get into what is called the joint stage. Grain planted in the fall sprouts and grows fairly rapidly. Once it sends up the stem that the grain head grows on, and it makes the first joint in that stem, if it gets about 10 degrees Fahrenheit it will kill the plant.

       To prevent this from happening, cattlemen and wheat farmers graze small grains with cattle. Without cattle grazing, the wheat, all wheat planted as well as oats, would have to be planted in the spring. Usually, moisture conditions remain too wet for this to work well.

       Without beef you can kiss goodbye probably to 50% of the earth's population.

       Another misconception is water supposedly taken up by cattle. Water weighs approximately eight pounds per gallon. A one thousand-pound steer, if 100% water, would be 125 gallons of water. Where is the rest of the thousands of gallons of water? If handled properly, the waste water from cattle is a very valuable resource. It removes nitrate nitrogens and ammoniacal nitrogens and returns them to the soil. Nitrate nitrogens make forage, and ammoniacal nitrogens make seeds and flowers. Farmers pay big money for these in bag form to apply to the land.

       And the second is by Mark Purdey from The Nutcracker Suite:

       One of the most nutty, stereotype fallacies. . .is the vegetarian claim that crop husbandry is less chemically and energy intensive than livestock farming. Whilst this is true in consideration of the intensive grain-fed livestock units, the traditional mixed farming unit raises livestock for meat and milk off extensively managed, low-input grassland systems; and each acre of well-managed grassland can produce four harvests a season of high-protein forage utilizing its all-inclusive clover plants as a green manure for fixing free atmospheric nitrogen into the soil. Whereas, an arable cropping system will only yield one or two crops per season and will largely remain reliant on the inputs of artificial fertilizer for its nitrogen source; one ton of which requires ten tons of crude oil in the manufacturing process. . .. Well-managed grassland is rarely sprayed with pesticide/fungicide/herbicide, not even on the most chemically orientated of farms. Yet virtually all vegetable and arable systems receive an average of ten chemical sprayings annually through from the initial seed stage to the final storage of the produce. Vegetables are so heavily sprayed that the more perceptive elements of the medical establishment have actually linked the victims of a mystery, novel neurological syndrome to the fact that they are all vegetarians in common. One team led by Dr. David Ratner from the Central Emek Hospital, Afula, in Israel, bloodtested several isolated cases of those suffering from this syndrome and found that various organophosphate pesticide residues intensively present in their vegetarian diet were responsible. Once the victims were convinced that they should return to a diet including meat and milk products, their symptoms and abnormal blood enzyme levels normalized rapidly.

       Moderator Response:

       [db] Off-topic snipped.

14158. sauerj at 02:01 AM on 13 July 2018
       Book Review: A Global Warming Primer, by Jeffrey Bennett
       

       Question: Does this book include a comparative review of the different forms of macro-economic solutions, those being: 1) Carbon tax (sub-set being rev-neutral tax), 2) Cap & Trade, 3) Command & control (classic gov regulations) and 4) Subsidies? ... A review of the macro-economics should come before any review of an itemized list of technological solutions. And, skipping the macro-economics all together would not, in my opinion, be an adequately comprehensive primer (leaving the reader critically ignorant on effective & timely implementation of mitigation solutions). ... Interlaced in the comparative review of macro-economics is the subject of political durability, a component of reality that must be considered in order to achieve the end goal, that being accelerated reductions in carbon emissions.
       I am truly curious if this books includes a review of macro-economic policies to achieve meaningful reductions in carbon emissions! If it does, then I will buy this book and pass it on, as, then, I would feeI that it "covered it all". If not, then I believe it is just another typical climate change book, that falls short on broadening the concept of 'solutions' beyond simply our own personal lifestyle changes or beyond an itemized list of technology solutions (since understanding & embracing such a macro-perspective is also a vital grassroot component in the politics & ultimate goal of achieving meaningful macro-level carbon emission reductions), as well as providing to the reader critical information on what are these fundamental cornerstone economic tools/policies and rating their effectiveness on achieving large-scale effective & timely carbon emission reductions.
       An adequate primer should (I think) push the reader beyond the confines of their own personal lifestyle changes or even the confines of an itemized list of technological solutions (such a 'micro' approach, by itself, will not be enough, by a long shot). Instead, an adequate primer should illuminate the reader to the concept & understanding of macro-economic policies (why this is necessary to achieving the end goal, and which policies are most effective). This is necessary, as well as, yes, pushing the reader to also make personal lifestyle changes & a basic grasp of all the presently known technological solutions.
       I speak from personal experience on this. I read many CC books over a course of ~6 years and never felt like I was getting fully educated on truly effective solution methods that would overcome the massive economic forces that gave FF energy 'inertial leverage' over competing sustainable efforts. I always felt that my personal heroic lifestyle changes did nothing but keep the price of FF down, and then others & industry (bound by the economic survival constraints of free enterprise) would be more than happy to burn the lower priced FF that I heroically tried to keep in the ground. Individually, I was fighting macro forces far beyond what I could effectively alter. I knew these concepts intituitively, but had no organization or authoritative education to grab hold of or be a part of. When such a macro-based perspective and economic solution finally came to me, in terms of clear articulation & an organizational community, it was extremely uplifting & empowering. This happened when I discovered, joined & was further educated by Citizens' Climate Lobby.
       Therefore, I think for a primer to due justice to adaquately educate a reader, it should provide this kind of macro or broader-level 'illumination'. This then opens the door to the reader on the kind of macro-based solutions that the reader intuitively feels is necessary to truly do the job, but simply lacks articulate understanding and a macro-level organization to plug into. Such a primer would also guide the reader to where he/she should focus their macro political energy. All of this is, of course, in addition to (going above & beyond) changes to their own personal lifestyle. Both grassroots efforts are necessary & should be part of educational primers with the goal of achieving meaningful declines in annual carbon emissions (declines of at least 2-4%, or more, per year).
       Supporting References to the above points:
       1) The Case for a Carbon Tax (Shi-Ling Hsu) ... LINK
       2) Guardian Article (Dana Nuccitelli) ... Quote: "81% said a market-based system (carbon tax or cap and trade system) would be most efficient" ... LINK
       3) Brookings Institute Interview (Adele Morris & David Victor) ... LINK
       4) Hansen (Book: 'Storms of My Grandchildre' and many other numerous papers and public statements)
       
       Organizations advocating for Carbon Tax Policies:
       1) citizensclimatelobby.org/
       2) www.clcouncil.org/
       3) www.afcd.org/
       4) www.carbontax.org/
       5) carbonwa.org/

14159. ilfark2 at 00:37 AM on 13 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       It would be nice to have a full debunking of that arctic news blogspot. I went to the "deep dive" on debunking Guy McPherson and the person dismissed the idea that methane could be released on a massive scale by noting sea temps had been about the same 200k yrs ago (and it didn't happen then) and also that Archer does some back of the envelope calcs showing it won't be a problem.

       Note though that GHGs were about half what they are now, 200k ago.

       Note Alley's work (as someone mentioned above).

       Note Archer's history on various parts of artic behavior (e.g., permafrost in which he didn't include the effect of microbes), which he always corrects himself later on. But notice how his timelines have changed over the last 15 years.

       The problem with arctic news blog is it's harder to debunk than McPherson. They do cite lots of papers. Some of it is new lines of inquiry, but the direction they point is quite dramatic (Sharkova et. al., e.g.).

       Considering PETM and Siberian Traps events happened around 500 — 1500 ppm CO2, and Alley has shown a very good case that global climate can change in a matter of 5 years, and we've trapped a great deal of heat in the ocean that hasn't come out to play yet and we already have 2ce as much CO2 as 200k ago...

       They make a good point as to the possibility.

       What they don't really flesh out is that, if there is a sudden climate flip and many crops fail along with massive drought, the global capitalist system could grind to a halt for a bit. This could lead to a lot fewer particulates in the air, which could lead to very fast (others have researched this pretty well from what I can tell) warming.

       So please, Skeptical Science, fully debunk these guys. Point out what they are missing in your usual ultra thorough manner.

14160. One Planet Only Forever at 09:59 AM on 12 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       nigelj@28,

       I agree, but would add that every future human needs equal consideration, without discounting the consideration of people in the future. And that makes it difficult to justify any unsustainable activity.

       I often quote a longer portion of the 1987 UN Report "Our Common Future" that includes "... We act as we do because we can get away with it ...".

       The follow-up to "Our Common Future" is "Back to Our Common Future" which is a summary of the UN's “Sustainable Development in the 21st Century” (SD21) project. That document includes specific mention of the need for all nations to include consideration of the future generations in their policy evaluations and decision making.

       And the Sustainable Development Goals, which include Climate Action, are all about consideration of the future generations.

       No rich or powerful person has an excuse to be unaware of this or to misunderstand the importance of sustainable development. The ones fighting against the increased awareness and understanding of the required change of direction of development, and the corrections of what has developed, clearly need to be effectively targeted for correction.

14161. nigelj at 07:37 AM on 12 July 2018
       Book Review: A Global Warming Primer, by Jeffrey Bennett
       

       Looks like a well written book. The book "An Inconvenient Truth" presented the issues well on the whole, but had nothing on the sceptical myths. Perhaps Gore did this deliberately to keep the book short, and to avoid giving the sceptics any publicity, but I feel it was a mistake. The sceptical pseudo science should have been shot down from day one without mercy.

14162. nigelj at 07:09 AM on 12 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       OPOF @26 &27, I can relate to the risk management issue, because I also work in a design profession, and we have both issues of risk, technical codes, and codes of practice and professional conduct. I think the dam analogy is quite compelling.

       The whole concept needs developing further. Psychological research has discovered we quantify risk and probability all the time in all our decision making. As we all know normally we manage risk on the basis of how probable the risk, so the more the probability of risk, the more caution we have. But we also quantify the level of risk, so very low probability extremely high risk scenarios can justify a lot of caution as well, especially if the outcome cannot be reversed. But I think we are not as good at this.

       And despite this, people do take enormous risks where the outcome is potentially certainly instantly fatal and probabilities are low for example extreme sports. They possibly regard the planet in the same way, and you dont need to be a genius to know which side of the climate debate they are likely to be on.

       Individuals perhaps think they can escape climate change risks, especially if they have plenty of money. This will ultimately not be so easy.

       The thing is with climate change it effects the entire planet, so while extreme scenarios are perhaps low probability, they are high risk, and also affect billions of people. In addition the costs of remedying a catastrophic climate scenario would be vast. Therefore  the community is surely justified in minimising the risk by taking a united approach.

       I think we do have to to convince people we are dealing with a potentially very high risk situation without exaggerating, or sounding like "chicken little" and inviting ridicule.

       For me the complexities of altruism and selfishness would be best resolved by simply evaluating policies on the basis of whether they are fair to all the people involved, (and ultimately this includes everyone in society). So for me it comes down to what is "fair and reasonable" and this is a key value people need to unite around, if we were to reduce the issues to the simplest possible form. Of course theres much more to it, but this is the simplest way of summing it up for me personally anyway.

14163. BaerbelW at 06:04 AM on 12 July 2018
       Climate Science blogs around the world
       

       Two Italian blogs have been added to the article:

       Climalteranti.it and Il Kyoto fisso

14164. One Planet Only Forever at 04:11 AM on 12 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       A further revision/expansion of my revision/expansion @26

       What I referred to as Engineering Risk Management is just an example of appropriate Risk Management. It is the approach that should be used to evaluate the acceptability of any human activity. The developed Business Risk Management approach I presented in my comment@5 is undeniably unacceptable.

       As a General Rule: Increased awareness and understanding of what is really going on (science, but also so much that isn't called science and can't be confirmed by experiments in a lab), is essential to advancing humanity/civilization. And the application of increased awareness and understanding needs to be governed/limited by thoughtful consideration to avoid harm to others (ethical altruism). Everyone who ethically altruistically self-limits their actions should be free to do as they please. Anyone who tries to act less ethically needs to be corrected. Anyone who resists being corrected needs to be kept from having any influence on others until 'they learn to change their mind'.

       That is not new. It is my 'newest way' of expressing something that has been presented many times before by many people including Plato's idea of Philosopher Kings. It is another way of addressing John Stuart Mill's warning about allowing people to grow up mere children. It also exposes that law making also needs to be governed by ethical altruism or the laws and their enforcement could be illegitimate/unsustainable.

       It is an understanding that seems to constantly need to be re-learned because of the tendency for people to allow their primal instinctive reactions to over-power their advanced human thoughtful consideration. Only the least fortunate, most desperate, have an excuse for allowing their primal needs to over-power their ability for thoughtful consideration.

       Regrettably, the Constitutions of many nations do not include this fundamental General Rule or Guiding Principle. As a result, their law making can be unjustifiably governed by unsustainable, but temporarily gotten away with, popularity and profitability.

       That General Rule undeniably makes the actions of people who deliberately develop misleading marketing messages against increased awareness and understanding of climate science undeniably harmful. And the 'more successful' such a person appears to be, the less acceptable their actions are.

       The shift of culture in America from a Culture of Character to a Culture of Personality was a significant unhelpful change that needs to be corrected (see Foot Note).

       Increasing the awareness and understanding that less ethical/altruistic actions can get away with an unjustified competitive advantage in freer competitions for popularity and profitability may help change the way people respond to messages, change what impresses them most. It may help them think about the reaction that the message triggered and evaluate whether that triggered reaction was helpful to developing a sustainable better future for humanity, helped achieve the Sustainable Development Goals - did not harm the achievement of any of the goals. Passion triggering messages can be helpful, but often they are knowingly being abused for harmful purposes.

       Foot Note:
       Part of what happened to ethics is the shift of recognition of merit from 'Justifiably Helpful to Others and the future of Humanity' to 'Populist Celebrity - measured by power, popularity and profitability'.

       Susan Cain's “Quiet: The Power of the Introvert in a World That Can't Stop Talking” refers to cultural historian Warren Susman's work identifying that America went through a culture shift from a Culture of Character to a Culture of Personality in the late 1800s and early 1900s. His evaluation included a review of self-help books where he identified the dramatic shift of terms used to describe the desired person (to the detriment of people wanting to be helpful developers of a sustainable better future for humanity).

       In the Culture of Character the most common terms were: Citizenship, Duty, Work, Golden deeds, Honor, Reputation, Morals, Manners, Integrity (behaviours that everyone could aspire to, including scientists). The terms most common in the new Culture of Personality are: Magnetic, Fascinating, Stunning, Attractive, Glowing, Dominant, Forceful, Energetic (behaviours that scientists should not aspire to in order to 'sell their increased awareness and understanding').

       That culture shift was a shift from valuing ethical altruism and the pursuit of increased awareness and understanding of how to be helpful to others, to distraction from the pursuit of sustainable improvement for humanity and excusing selfishness and individual freedom of belief and actions.

14165. michael sweet at 01:56 AM on 12 July 2018
       Water vapor is the most powerful greenhouse gas
       

       It appears that Cosmoswarrior is back again. 

       Moderators: good luck and keep up the good work.

       I have recently been reading a lot of comments at RealClimate and their comment threads are severely clogged by two spammers.  (their OP's continue to be terrific and very informative).  Tamino is also discussing this problem.

       I think that SkS's decision to remove the spammers is the best way to go.

       Moderator Response:

       [DB] Yes, it was yet another iterative and boring sock puppet of serial spammer Jeff Dylan/cosmoswarrior/et al.  No further replies to it are necessary as its posting rights have been rescinded.  

       As will happen to all future iterations of such.  Be forewarned, Jeff.

       

14166. Eclectic at 22:39 PM on 11 July 2018
       CO2 lags temperature
       

       Tcflood @576 , certainly for me there was some "unclearness" in the messages from Schmidt and Dana.   Maybe in their comments they did not choose to spend time going into meticulous details of the time-lines and/or regional variations [such as in the northern Pacific?] involved in the glacial/interglacial transition phase.   Or maybe those details have not yet been determined exactly.

       Nevertheless, the important "take home" message is that of (a) an initial warming from Milankovitch orbital effects, causing (b) warming oceans to release CO2 which provides the bulk of subsequent global warming.   Which is always an excellent point for rebutting those tiresome denialists' claims of "no CO2/temperature causative relationship".

14167. TornadoWatch at 16:38 PM on 11 July 2018
       Water vapor is the most powerful greenhouse gas
       

       Eclectic@279

       I'm sure that albedo has its part in establishing temperatures, but that is not the issue here. The issue is in correctly calculating the greenhouse effect for water vapor. Now, James Frank and John Cook of this webpage along with Lacis et. al. (referenced by Dan Bailey@278) have claimed that water vapor and other condensable GHG cannot be a forcing of temperature since they too short-lived in the atmosphere to cause much greenhouse heating. TD@267, however, points out that GHG molecular atmospheric lifetimes are irrelavent in determining such heating. I won't argue that point at this time, but I think you would agree that we must at least be consistent. Therefore, if there is no temperature forcing due to the water vapor greenhouse effect, then there is no feedback to a rise in temperature either. There can only be one value for the H2O greenhouse heating, not two different values for forcing and feedback. Of course, with no H2O feedback, there will be no amplifying the CO2 greenhouse heating and no CO2 "control knob".

       Moderator Response:

       [TD] You misinterpreted Frank, Cook, and Lacis et al. by thinking they claimed that condensable GHGs cannot be forcings solely because individual molecules are too short-lived in the atmosphere. What actually is being "claimed" is that throwing into the atmosphere, more molecules of water vapor than the atmosphere can contain at the atmosphere's current temperature, results in that extra number of molecules (regardless of which individual molecules those are) quickly to fall out of the atmosphere without replacement of that fallen extra number, so that the total number of water vapor molecules in the atmosphere quickly returns to its original, lower value.

       The original, lower value (equilibrium number of water vapor molecules) is maintained as water vapor molecules are thrown into the atmosphere by evaporating from the vast pools of liquid water that always are present around the world, followed by an equal number of water vapor molecules condensing out. If you throw extra water vapor molecules into the air, a molecule condensing out will not quickly be replaced by another molecule evaporating, because there is no room in the atmosphere at the atmosphere's current temperature. Therefore adding water vapor without first or simultaneously increasing the atmosphere's temperature by some other means, cannot force the temperature higher.

       In contrast, if the temperature of the atmosphere is increased by some other means, more water molecules will make the leap from liquid to gas, and when they condense out other water molecules quickly will take their place, thereby creating and maintaining a larger total number of water vapor molecules in the atmosphere at any given moment. So an increase in temperature by any other means causes an increase in total number of water vapor molecules--a feedback to whatever caused that initial increase of temperature.

       Non-condensing GHGs such as CO2 have no such temperature limits on the total numbers of molecules that can exist in the atmosphere at a given time. So throwing more of them into the atmosphere results in them just staying there, for a really really really long time until other mechanisms remove them.

14168. One Planet Only Forever at 13:23 PM on 11 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       Reading the recent comments and thinking more about what needs to be done, I am revising/expanding my comment@5.

       I will, however, preface this by saying that the most important challenge to overcome is the ability of the less ethical among the wealthy and influential people to get away with misleading marketing appeals triggering passionate unjustified responses in support of excuses for causing harm to the future generations of humanity (appeals that make people primitively react selfishly and resist performing the more advanced human activity of thoughtfully considering things to help improve the future for humanity).

       It is important to understand the difference between Engineering Risk Management and Business/Economic Risk Management.

       I presented a common Business Risk Management method in my comment@5. In addition to liking to have others suffer any negative consequences, the business/economic approach attempts to justify what is done (claiming it is acceptable) by discounting future negative consequences and comparing that reduced perception of harm being done to others with the perceived lost opportunity (or cost) that some people today would experience if the amount, or risk, of future harm to others was reduced.

       Engineering Risk Management is different. It strives to reduce the chances of negative future consequences. The way it works is evident in the development of Building Codes and design codes for special items such as Dams. It is important to severely limit what is allowed because once harm has been done it can be very difficult to properly compensate those who were harmed and properly penalize those who benefited from the riskier more harmful approach.

       Canadian, US and many other Building Codes are based on designs statistically having a small chance of experiencing an event that would result in damage to any part of the structure. And the design of the structure would strive to allow all the occupants to be safe and safely exit the building even though the building is now damaged and may no longer be able to be used. The code minimum requirements are established to ensure that the statistical probability of damage occurring to a building is limited to a 1 in 50 year event (like a 2% chance of occurring).

       The requirements for Dams are typically more stringent because of the amount of harm that could be caused by the dam failing. A common requirement for dams is that they be designed to safely manage a 1 in 100 rain event without wave action resulting in any water reaching the top of the containment features of the dam, and be capable of holding the expected water from at least a 1 in 1000 year event without risk of failing. That is like protecting against an event with a 0.1% chance of occurrence.

       And with the Building Code and Dam Requirements, it does not matter how much cheaper or quicker an alternative is. The minimum requirements must be met. In a way, the codes set hard limits on economic/business options. And engineers are ethically responsible for not budging on those hard limits.

       For an issue like climate change (and so many other things), the Engineering Risk Management approach should be applied, setting hard limits on Business/Economic considerations and the way that options are evaluated. Engineering Risk Management also screens out (eliminates/dismisses) options that would result in harmful future consequences. Those options don't get to be considered no matter how desirable those options may be to someone or some group.

       The risk avoidance criteria for Dams is based on lower probability extreme events than the criteria for a building. The criteria for the planet should be based on lower probability extreme events than is used for Dams. I have seen many reports of evaluations indicating that humanity could experience livable conditions on this planet for hundreds of millions of years (before the changes of the Sun result in climate change that makes it too difficult to sustain life). Perhaps 1 in a billion is the more appropriate Engineering Risk Limit basis for global livability impacts like climate change impacts.

       That is essentially the same as the common sense understanding that it is unacceptable for any portion of current day humanity to be benefiting in a way that causes negative consequences for future generations.

       That would be the result of ethically altruistic thinking, pursuing increased awareness and understanding of what is really going on in pursuit of the development of sustainable improvements for the future of humanity and, as a minimum, protecting the future of humanity from harmful consequences.

       Science is by default, when being done properly, Ethically Altruistic. At its best it, a-politically and without potential bias for economic benefit, develops improved understanding and identifies required corrections, including corrections of economic and political developments.

       So the 'climate alarmist' evaluations deserve to be rigorously evaluated. If they are found to be 'based on good reasoning and are more probable than 1 in a billion' then the most severe of those probable events should be promoted as the proper basis for economically evaluating the acceptability of developed actions, and alternatives being considered, by the current day population.

       Attempts to defend much of what has economically/politically developed, including attempts to defend the failure of leadership (political and business) to responsibly limit the creation of additional climate change impacts will inevitably fail such an evaluation. It is common sense that what has developed cannot be justifiably defended.

       The lack of responsible actions from the wealthier and more powerful people can only be excused by misleading marketing claims. That must be corrected; the sooner the better, no matter how unhappy some people are about being told that they have developed unacceptable desires and are required to change their mind and actions.

       SkS cannot help but be Politically Correcting. People claiming that it is unacceptable for SkS to be seen as political, meaning politically biased, need to be challenged to justify why they want to protect understandably unacceptable developed economic and political beliefs from being corrected. Why do they want to believe that Ethical Altruism should not be limiting or correcting Egoism/Selfishness?

       Another way to say that is that SkS strives to be ethically altruistic, which can only be perceived to be Political if some political groups have allowed egoist/selfish desires to over-power their human ability to thoughtfully consider their actions, over-powering the ethical altruistic interest in striving to be more aware and better understand how to help develop sustainable improvements for the future of humanity.

14169. tcflood at 13:00 PM on 11 July 2018
       CO2 lags temperature
       

       Eclectic @575

       Your explanation paints a consistent picture with Schmidt's comments and makes sense. Dana's comments when taken at face value still seem to me to be a little unclear.

       Thanks for taking the time to respond. 

14170. nigelj at 12:30 PM on 11 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       "I hear you but my concern is that the denialists are constantly reminding the average Joes out there (like me) of exaggerated or unfulfilled predictions, including distorting them.'

       This is my concern as well. Saying stupid stuff like "climate change will cause human extinction within 30 years" is not going to convince either denialists or "fence sitters". Such claims are easy to ridicule and disprove.

       What will be more likely to convince fence sitters are defensible projections with some evidential basis. This would include sea level rise towards 2 metres or maybe slightly more this century, serious lethal heatwaves, and the possibility of abrupt climate shifts and other things. That is "alarming enough" and can be substantiated with evidence, historical examples, and physics. 

       And it all comes done to how we define "alarmist" and of course nobody is going to really agree on this. It's a term that will continue to be thrown around like throwing mud. I tend to think while I dislike the term, it's best to "take it on the chin" and say maybe we are being alarmist, but with pretty good cause. But you then have to be able to back your position with good evidence and facts.

       Politicians are often "alarmist" . Sometimes their alarmism works, but sometimes it doesn't when people see through them. Extreme alarmism is a risky card to play.

       Ultimately you have to be able to credibly back your position. J Hansen is obviously some sort of genius, but for me straddles the ground between the possible and the impossible and his sea level rise predictions require a lot of conditions to occur. One should however justifiably argue even the remote possibility he is right is enough to justify urgent action.

       Of course the denialists often twist sound predictions to make them sound false, for example using Hansens scenario A predictions when the only prediction that makes sense is scenario B. But thats another matter. It seems like theres no option but to patiently rebut this sort of thing, or is there another way?

14171. Johnboy at 10:31 AM on 11 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       Michael Sweet @ 12. I hear you but my concern is that the denialists are constantly reminding the average Joes out there (like me) of exaggerated or unfulfilled predictions, including distorting them. They often get away with equating alarmism with climate science in the eyes of the public. I think the scientists need to get out front of this to continue to bring the fence sitters into the fold.

14172. MA Rodger at 08:13 AM on 11 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       Sir Charles @21-24,

       The primary source may be an proper point of referenece.  And that is Fischer et al (2018) 'Palaeoclimate constraints on the impact of 2 °C anthropogenic warming and beyond'

14173. SirCharles at 07:40 AM on 11 July 2018
       There are genuine climate alarmists, but they're not in the same league as deniers
       

       

        

       Watch the concert here => https://www.youtube.com/watch?v=9a6JeqX1BHI

       Moderator Response:

       [DB] Please restrict image widths to under 500, please.

14174. SirCharles at 07:32 AM on 11 July 2018
       There 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.

       => Global warming may be twice what climate models predict

14175. Evan at 06:54 AM on 11 July 2018
       There 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.

14176. nigelj at 06:48 AM on 11 July 2018
       There 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.

14177. nigelj at 06:44 AM on 11 July 2018
       There 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.

14178. Daniel Bailey at 05:37 AM on 11 July 2018
       There 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"

14179. michael sweet at 05:35 AM on 11 July 2018
       There 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.

14180. Evan at 03:24 AM on 11 July 2018
       There 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

14181. sauerj at 02:56 AM on 11 July 2018
       There 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".

14182. rocketeer at 02:29 AM on 11 July 2018
       There 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.

14183. michael sweet at 02:12 AM on 11 July 2018
       There 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.

14184. michael sweet at 01:58 AM on 11 July 2018
       There 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.

14185. Johnboy at 01:48 AM on 11 July 2018
       There 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. 

14186. Evan at 00:52 AM on 11 July 2018
       There 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.

14187. jef12506 at 00:42 AM on 11 July 2018
       There 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.

14188. Evan at 23:50 PM on 10 July 2018
       There 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.

14189. agno at 21:32 PM on 10 July 2018
       2018 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.

14190. Eclectic at 17:11 PM on 10 July 2018
       CO2 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.

14191. MA Rodger at 17:07 PM on 10 July 2018
       Increasing 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.

14192. tcflood at 15:25 PM on 10 July 2018
       CO2 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?

14193. scaddenp at 13:59 PM on 10 July 2018
       Increasing CO2 has little to no effect
       

       jesscars - I have responded on a more appropriate thread here. Any discussion of past climate should go there.

14194. scaddenp at 13:58 PM on 10 July 2018
       Climate'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.

14195. Eclectic at 13:45 PM on 10 July 2018
       Increasing 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 !!

14196. jesscars at 13:36 PM on 10 July 2018
       Increasing 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:

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14197. wili at 13:11 PM on 10 July 2018
       There 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.

14198. scaddenp at 12:08 PM on 10 July 2018
       Increasing 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.

14199. scaddenp at 11:44 AM on 10 July 2018
       Increasing 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.

14200. jesscars at 11:38 AM on 10 July 2018
       Increasing 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:

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