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Comments 27751 to 27800:

27751. bozzza at 12:49 PM on 8 September 2015
       2015 SkS Weekly Digest #36
       

       I was always taught that 'e' certainly does not equal 'mc²'....

27752. BBHY at 11:25 AM on 8 September 2015
       2015 SkS Weekly Digest #36
       

       "...temperature and carbon fluctuate in tandam at fairly regular intervals over the last 400K years"

       Is that a reference to Milankovitch Cycles? It sounds like it is, but those are not limited to only 400K years.

27753. Tom Curtis at 10:02 AM on 8 September 2015
       2015 SkS Weekly Digest #36
       

       Ignaz @2:

       "...a talk by William Nordhaus at Yale, certainly no denier, where he showed the number of data dependencies in models, that have not been isolated..."

       At 7:23 in the video, Nordhaus is talking about the fact that different estimates of climate sensitivity use the same or overlapping data to make those estimates, ie, the same twentieth century temperature record and the same twentieth century forcing record (in some cases), or the same ice core records (in others).  It follows that those estimates are not stastically independent.  That has nothing to do with the independence of climate models.  You have completely misrepresented what Nordhaus was saying (through ignorance, I suspect).

       "However, as of 2013 we do not know to what extent carbon forces temperature and temperature forces carbon..."

       Nonsense, and nor is it what Nordhause is saying.  Specifically, we know that CO2 concentration increases by approximately 7.7 ppmv per 1 degree increase in global temperatures (likely range of 1.7-21.4 ppmv/^oC).  Nodhaus's estimate comes out at a 2.23% increase per degree C, or 6.3 ppmv/^oC at 280 ppmv initial CO2 concentration.  We also know that temperature increases relative to CO2 concentration at approximately 3^oC per doubling of CO2 (likely range of 1.5-4.5⁰C per doubling).

       Not knowing values to arbitrary precision is not the same as not knowing the values.  Nor does Nordhaus suggest it is.  His discussion of what we know relates only to the limits of the method he discusses in his video.  Multiple other methods can be, and have been applied to the problem.

27754. scaddenp at 09:42 AM on 8 September 2015
       2015 SkS Weekly Digest #36
       

       Noone is claiming that the veracity of a scientific question is settled by vote - the extent to which anything in scence is "true" is dependent on constant comparison of theory and results by experienced scientists. The opinion of relativity deniers doesnt weigh much unless one them someday publishes a reproducable result which would call the theory into question and this applies in climate too.

       The importance of understanding what the extent of consensus is among climate scientists is a/ to counter the denier myth that consensus doesnt exist and b/ because the consensus science position is the best guide to policy action in any sphere.

       Weather is chaotic, climate is not as far as we know. See here .Climate is determined by the energy balance and sets the bounds in which the complex dance of weather occurs. Ask yourself why summer average temperature is higher than winter average temperature - because the energy input into the system is higher. CO2 is likewise.

       CO2 can be both a forcing and feedback. In the ice-age cycle, the controlling forcing is the highly predictable change in solar distribution. CO2/CH4 are very slow feedbacks that magnify the effect of the solar forcing and fortunately, temperature-induced increases in CO2 and CH4 are slow enough not to have significant impact in next hundred years.

       "However, as of 2013 we do not know to what extent carbon forces temperature and temperature forces carbon, or excatly why they fluctuate if indeed one expects a reenforcing feedback loop is present."

       What on earth is your source of this claim? If Nordhaus, then he is wrong. See for instance Hansen and Sato 2012 - look at Fig 2, and lower 2 comparisons of calculated temp to measured.

       It is best to find out about science from scientists. The best way to do that would be to read the IPCC WG1 reports. All the text in main report linked back to published science that the text is based on.

27755. Tom Curtis at 09:41 AM on 8 September 2015
       2015 SkS Weekly Digest #36
       

       Ignaz @2, if E=mc², then it is not true that F=ma.  Rather,

        

       where

       

       and a∥ is the acceleration parellel to the instantaneious velocity of the object, and a⊥ is the acceleration perpendicular to that velocity.

       This is not mere pedantery.  If you are going to argue that "we know" not by scientific concensus but by the actual data, then you have to adopt a consistent perspective that fits that data, not swap between more exact and less exact (and falsified) theories in a single breathe.  That you treat equally to formulas, one of which is the best available (ie, not formally falsified and substantially tested) theories and an approximation retained by consensus as a convenience for many common situations seriously damages your thesis.

       Even more damaging is that the approximation is adequate for everyday experience.  More devestating for your case is the fact that the much worse approximation from Aristotelian dynamics is still adequate for the vast majority of peoples actual experience.  It is only when we measure the motion of objects in a precise manner that Aritstotle's theory (or at least the medieval developments of that theory) are shown false.

       The result is that for me, and the vast majority of others; we do accept that E=mc², and F=ma because (we have been told that) it is the consensus view of physicists.  No person with only a high school education in physics has done enough experiments to verify Newtonian dynamics as a close approximation of the truth, let alone Relatitivistic kinematics.  Very few actual physicists have done so either.  Even for most with an actual interest in the topic, they are only aware of a few historically influential experiments, without being aware of the vast number of other experiments actually supporting the theories in question.

       So, we (as in the fraction of the general populace interested enough to actually follow the science) know these things (whether in dynamics, kinematics, or climate science) because we accept a scientific consensus, and know enough that the consensus itself  was not formed by accepting a consensus but by following data.  But unless you have an extensive research career covering both theoretical and experimental aspects of the topic, you do not know these things independently of accepting some things because they are the consensus view.  (Indeed, even then you must accept the consensus on peripheral factors necessary to carrying out your experiments.)

27756. Ignaz at 05:56 AM on 8 September 2015
       2015 SkS Weekly Digest #36
       

       Question: Do we accept the veracity of E=MC² or F=MA because 97% of  physcists say so?
       
       I understand that climate is a nonlinear chaotic system, but it's that a reason to be even more circumspect? I recently heard a talk by William Nordhaus at Yale, certainly no denier, where he showed the number of data dependencies in models, that have not been isolated. Specifically, when we look at paleoproxy data we see that temperature and carbon fluctuate in tandam at fairly regular intervals over the last 400K years. However, as of 2013 we do not know to what extent carbon forces temperature and temperature forces carbon, or excatly why they fluctuate if indeed one expects a reenforcing feedback loop is present.
       
       Has this issue been addressed and resolved?
       
       (Nordhaus' pertinent comments at 7:22) https://youtu.be/Wr_2RKnCqNQ

27757. johnsnz at 04:56 AM on 8 September 2015
       2015 SkS Weekly Digest #36
       

       This is where our expectations of science went terribly wrong.

       Tol takes issue..saying its only 91% consensus not 97% as John Cook claimed. But its unusual to adopt a denial stance when you already know you believe its at least 91% probable that John is right all along?

       The scientific truth begins when at least a 95% probabilty is reached. 91 is only 4 away from 97 or 4% of it. Both figures are so high as to mean the very same thing our planet is troubled and we are the only ones who can do anything about it.

       We need wake up now, stop wasting time on semantics, modify/fastrack our methods considering all, first looking for medium strong trends and only then distilling out the scientific. 

27758. Sunspot at 02:50 AM on 8 September 2015
       What Emma Thompson got right and wrong on climate change
       

       Then again, everyone admits that the predictions back in 2000 were much too conservative, things are changing much faster than anyone would have believed 15 years ago. We are entering uncharted waters, and it becomes more difficult to predict these changes. There is clear and present danger, whether things get to a certain point in ten years or twenty is of course important, but some things are truly unpredictable and all predictions at this point should still be regarded as likely understated.

       Today, tomorrow, and the day after will be 15-20 degrees above normal here in New England, and the forcast is for more heat next week. This is getting very suspicious already...

27759. One Planet Only Forever at 02:08 AM on 8 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Digby Scorgie,

       From my perspective it is more imporant to ask them to explain things. And what I would ask them to explain are:

       • The history of CO2 levels in the atmosphere and the rapid recent increase. Why the rapid recent increase? Use the resources in the course to ensure that the facts of CO2 levels through the past 800,000 years are clearly understood.
       • What do they believe the effects of CO2 in the atmosphere are? What is the science of CO2 related to incoming solar ratiation and outgoing infrared radiation from the surface. Ask them to provide a rational explanation with references to peer-reviewed publications. Correct any clear misuderstanding with information from this course.
       • Based on their, potentially new, understanding about CO2 in the atmosphere ask them if they have changed their mind. If they have, then share the course link and encourage them to delve into the fuller understanding of what is going on.

       If they won't understand the CO2 issue you have found someone who has decided to resist being convinced. Ask them what is motivating their deliberate reluctance to understanding what is going on. They probably will not answer but I am sure they will understand that some unacceptable personal interest is motivating them. That acknowledgment is the first step toward the required change of made-up minds that have been easily impressed by made-up claims.

27760. Stranger8170 at 00:39 AM on 8 September 2015
       Climate change and Hurricane Katrina: what have we learned
       

       Tom Curtis, your response to Ignaz was terrific!  I know that the moderators might delete my post if I say that  Ignaz is  intellectually dishonest, so I won't.

27761. Javii at 00:17 AM on 8 September 2015
       A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
       

       Just registered only to thank you for such a damn good article!

27762. Tom Curtis at 23:57 PM on 7 September 2015
       Climate change and Hurricane Katrina: what have we learned
       

       First, Ignaz @5 has plagiarized from wikipedia, which states:

       "On April 5, 2006, months after independent investigators had demonstrated that the levee failures were not due to natural forces beyond intended design strength, Lt. Gen. Carl Strock testified before the U.S. Senate Subcommittee on Energy and Water that, "We have now concluded we had problems with the design of the structure." He also testified that the U.S. Army Corps of Engineers did not know of this mechanism of failure prior to August 29, 2005. The claim of ignorance is refuted, however, by the National Science Foundation investigators hired by the Army Corps of Engineers, who point to a 1986 study by the corps itself that such separations were possible in the I-wall design."

       You will notice that his wording is exactly copied by Ignaz without attribution, following his clause, "Although the Army Corp of Engineers initially asserted that the levees would have failed even if the design flaws had not been present ...".

       Second,  despite Ignaz's willingness to quote (without attribution) from wikipedia, he neglects to quote wikipedia when it says:

       "According to Professor Raymond Seed of the University of California, Berkeley, a surge of water estimated at 24 feet (7 m), about 10 feet (3 m) higher than the height of the levees along the city's eastern flank, swept into New Orleans from the Gulf of Mexico, causing most of the flooding in the city. He said that storm surge from Lake Borgne travelling up the Intracoastal Waterway caused the breaches on the Industrial Canal."

       To illustrate this point, consider the following map of part of the flooded areas in New Orleans following Katrina:

       

       The map comes via a USGS article, that states:

       "The storm surges produced by Hurricane Katrina on August 29, 2005, breached the levees protecting New Orleans in numerous places, flooding approximately 75 percent of the metropolitan area. Most of the levee failures were caused by overtopping, as the storm surge rose over the top of a levee and scoured out the base of the landward embankment or floodwall. Three major and costly breaches appear to have been caused by failure of the soils underlying the levees or failure of the earthen levee embankments themselves; in several places, levee foundations failed when water levels were below the tops of the levees."

       (My emphasis)

       The blue stars on the map indicate locations where the levies were overtopped, and the redstars locations of structural failure in the levies.  As can be seen, most of the flooding in this restricted area came from levies being overtopped, and even in the locations where structural failure was a significant factor (New Orleans East Bank and New Orleans East), there was also flooding due to overtopping of levies.  In the areas effected by structural failures, therefore, those failures made flooding worse - but flooding would still have occured without the failures.

       As this larger map of the flooding (below) indicates, the area in the map above represents only a subsection of New Orleans and of the flooding.  The flooding outside of the area of the map above is all due overtopping of levies (as I understand it).

       

       So, in addition to a bout of plagiarism, Ignaz has taken the summary of reports that show the majority of the flooding and much of the damage to have been due to overtopping of the levies and interpreted them to indicate that effectively all of the damage was due to structural failure.  That is, he has egregiously misrepresented the findings of the various inquiries into the flooding resulting from Katrina.

       It may be noted that his failure to properly note and cite his quotation also served the purpose of (temporarilly) hiding his misrepresentation.

27763. Rob Honeycutt at 23:36 PM on 7 September 2015
       The cause of the greatest mass-extinctions of all? Pollution (Part 1)
       

       dudo39... The first "question" is completely irrelevant to the main topic of mass extinctions, the second question is merely asking why your irrelevant question was moderated.

       I'm still not seeing a question that requires a response.

27764. Tom Curtis at 23:00 PM on 7 September 2015
       Citi report: slowing global warming would save tens of trillions of dollars
       

       Ignaz @13, I think you are right to point out the financial interest of Citi group in the issue.  However, you have the sign wrong.  Citi group is an insurer.  That does not mean they are likely to make large profits from tackling climate change.  Rather, it means they are exposed to large losses if we do not tackle climate change.  That is due to the increased rate of climate related natural disasters in a warming world:

       

       Of course, tackling climate change is no no benefit in reducing insurance losses if climate change does not in fact drive increased natural disasters.  That is, they only have a financial interest in telling us about climate change if climate change is in fact real, and harmful.

27765. michael sweet at 22:55 PM on 7 September 2015
       Climate change and Hurricane Katrina: what have we learned
       

       Ignaz,

       This article describes the strength of hurricanes and sea level rise and how heey affect damage.  The levees in New Orleans are not germaine to the discussion.  Your comment is off topic.

       Please provide a citation for your claim that the 1881 hurricane was stronger than Haiyan.  In any case, Haiyan was the strongest hurricane recorded at landfall in the history of carefully recorded data.  You are trying to minimize record strength at landfall.  That is small consolation for the people who have to weather stronger and stronger hurricanes at landfall.  The fact that in the past occasional hurricanes were as strong as current ones does not compensate for the increase, caused by AGW,  in the strongest hurricanes.

27766. Kevin C at 21:59 PM on 7 September 2015
       Citi report: slowing global warming would save tens of trillions of dollars
       Ignaz: I'm interested in the evidence for your statement '[Citi group] stands to make hundreds of billions if not trillions of dollars depending on government policy on this issue'. From the context I presume that you are saying that Citi will *make* money if the decarbonization pathway they are suggesting is adopted. Further, you seem to be suggesting that this is a bad thing, so that presumably the money will be made at the expense of the economy in general, or possibly at the expense of the government, rather than as part of a corresponding benefit to the rest of the economy.I presume part of this is based on a detailed study into Citi's investment portfolio and risk exposure. Could you fill in some of the details for us please?The other part - how Citi benefits at the expense of the economy in general is more obscure. Can you explain where this comes from?
27767. Ignaz at 18:32 PM on 7 September 2015
       Climate change and Hurricane Katrina: what have we learned
       

       Katrina came ashore in Louisiana as a Category 3 hurricane with sustained winds of 125 mph, and a two part storm surge that was not particularly impressive (12-16ft). It has been well documented by civil authorities and the Army Corp of Engineers that the hurricane was not the main cause of the devastation visited on New Orleans. The cause of the devastatoin was poor levee design and construction by local and federal government authorities. Although the Army Corp of Engineers initially asserted that the levees would have failed even if the design flaws had not been present, on April 5, 2006, months after independent investigators had demonstrated that levee failures were not caused by natural forces beyond intended design strength, Lieutenant General Carl Strock, Chief of Engineers and Commander of the Corps of Engineers, testified before the United States Senate Subcommittee on Energy and Water that "We have now concluded we had problems with the design of the structure." He also testified that the U.S. Army Corps of Engineers did not know of this mechanism of failure prior to August 29, 2005. The claim of ignorance is refuted, however, by the National Science Foundation investigators hired by the Corps of Engineers, who point to a 1986 study by the Corps itself that such breaches were possible in the I-wall design.
       
       Amazingly, however, the word 'levee' does not even appear once in this post. It's more than a bit disingenuous for Kerry Emanuel to use Katrina, and government incompetence, as an example of AGW effects. 
       
       In the case of Typhoon Haiyan, it is also well documented that, a) category 5 typoons are not historically unusual in that part of the world, b) the effects of Haiyan were amplified by the fact that it funnelled straight into Leyte Gulf and San Pablo In addition, it was not the most devesating typoon to hit the Philipines. That distinction belongs to a typoon which hit the islands in 1881, well before, pardon the pun, global warming was a gleam in anyone's eye.

27768. Ignaz at 17:33 PM on 7 September 2015
       Citi report: slowing global warming would save tens of trillions of dollars
       

       If a study disconfirming your expectations were funded by the fossil fuel industry, I'm sure a howl of protest would rise from this blog - never mind ad hominems. However, a study confirming your thesis comes from an bank, that stands to make hundreds of billions if not trillions of dollars depending on government policy on this issue, and it's lapped up unquesiontingly? Not to mention no one seems to question the bank's clairvoyance, guessing what expenditures and costs may or may not turn out to be over a hundred year period, when they couldn't predict the meltdown of 2008 when they had all the data in front of them! Am I the only one that sees a problem with this?

27769. bozzza at 14:56 PM on 7 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       .. in summary: FOX won't change its message because its message is merely one of obfuscation that can be morally defended on spurious grounds from the very start.

       It's like a kid asking endless questions who never listens to the answers: it's idiotic and you just have to accept there is no conversation possible.

       We are a specious species...

27770. bozzza at 14:37 PM on 7 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       @9, the fake conservatives have always sold stuff and this means constantly entertaining two ideas at once. Nuclear Power has always been flogged as the cure for climate change going back to the 60s....

       "... but, but, but wait: there's more!!"

        

       They just want a captive audience on the hook and only when they get the feedback that the game isn't working will they switch to a new method.

        

       Entertaining the middle postion is always possible: some call it walking both sides of the street at the same time and some call it compromise- it's all in the language and how much the captive audience lets you get away with. The worlds always been run by psychos: such is the role of enterprise.

27771. scaddenp at 14:24 PM on 7 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Just wander over to any denialist web site  and you can soon find plenty to play with. Send a letter to the editor  to your local paper demanding action on climate change and you will have local deniers after you in force.

27772. Digby Scorgie at 14:01 PM on 7 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Well, not having a denier on hand to experiment with, I'm going to abandon my idea.

       As an old man with no children to fear for, I find myself in the position of an observer monitoring an interesting experiment:  Will the deniers continue to sabotage climate action until it's too late, or will they be overruled in time?

27773. juan vicini at 10:40 AM on 7 September 2015
       Breathing contributes to CO2 buildup
       

       1. isn't most of the swallowed CO2 plus the amount of CO2 produced from digestive processes, absorbed by the intestine, therefore by swallowing power plant co2 through cola arnt we sinking CO2 into fat, is all CO2 in human food obtained from organic sources through photosynthesis, if not how much mineral carbon is in our food?

        

       2. If over all human population growth and the resulting increment in food intake translates into a net depletion of the top of the food chain (excluding whales who eat plancton directly) live biosphere in the oceans, wouldnt that translate into an overall increase in CO2 in the atmosphere resulting from incremental of human respiration? pound per pound does human respiration more eficient than fish respiration in terms of oxygen intake vs CO2 outflow?

       3. Humans are getting very close to applying C as a material to very "usefull" purposes, and more that any other technology out there CO2 recapture tech. will be most responsible for it given that it isnt just regular C laying about that is most useful, but rather the one that is excited to very high temperatures. Hopefully we wont depleate the atmosphere of CO2 then. 

        

27774. scaddenp at 07:34 AM on 7 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       I've tried this Digby and wish you the best of luck. Basing your opinions on data rather than tribal values is not something that humans do naturally and on the whole, I think scientists only do it marginally better than general population. A well-trained, real skeptic confronts questions with "what data would cause me to change my mind?", and checks whether it exists. The normal response is a frantic search for data to back our existing position.

       However, the scientific approach does have value in talking to skeptics if they are not too vested in denial. The commonest response that I have seen is to demand data validating predictions that science doesnt make (eg Tristran point A or that temperatures rise uniformly with CO2). In challenging this, someone engaged is forced to look at what the science actually does say - a massive step forward from Fox news or denialist blogs.

       However, if someone is vested in denial, then they will typically just retreat to safe denialist blogs and disengage from you. Favourite outs are that climate is just too complex too understand so nothing can be known; science cant be trusted as scientists are just chasing money (a wonderful piece of projection), and at worst, that there is global conspiracy for something and any inconvenient data is manufactured by evil scientists bent on world domination. Remember the cardinals that refused to look through Galileo's telescope.

27775. michael sweet at 02:45 AM on 7 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Tamino recommended this video which gives a recommendation for a general discussion where you want to change another persons position.  I thought that the points the speaker makes are good and will try to use them in the furute.  He suggests that arguing the facts with a denier (which is mostly what I have done in the past) is ineffective and does not get people to change their views (even when your facts are correct).  He has suggestions for a better way to address the conversation.

27776. Tom Peel at 01:50 AM on 7 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Digby, in my experience no evidence has ever convinced a denialist to change his position.  What happens is that at some point deniers will not dispute whether global warming is taking place. They will simply say that climate has always changed in the past and therefore whether humans are responsible for the change right now is irrelevant. 

27777. Jim Eager at 00:27 AM on 7 September 2015
       Climate change and Hurricane Katrina: what have we learned
       

       Ryland, you are confusing saying a) there will be more powerful hurricanes, with b) there will be more hurricanes period. Emanuel does not say the latter, he says the former.

27778. shoyemore at 00:21 AM on 7 September 2015
       Climate change and Hurricane Katrina: what have we learned
       

       Re: ryland #2

       To quote the article linked:

       Although Landsea doesn't dispute that humans are causing climate change, he does doubt the assertion that global warming has significantly increased hurricane activity. To explain his doubts, he points to the imperfections in hurricane records.

       Above, Professor Emanuel says:

       Theory and computer models show that the incidence of the strongest hurricanes – those that come closest to achieving their potential intensity – will increase as the climate warms, and there is some indication that this is happening. But these most destructive, high-category storms constitute only around 12% of the world’s tropical cyclones; the great majority do little damage but occur far more often.

       These are not mutually contradictory - Emanuel is saying that there will an increase in the "most destructive, high category" storms, while Landsea is talking about ALL hurricanes.

       If Emanuel is right, we better get ready. If we delay in the hope that Landsea is also correct on extreme storms, and if he is wrong, then we (or a lot of people, somewhere) are screwed.

       Incidentally, if you read father down your link, you will find NASA scientists who support the view of Professor Emanuel's article.

       

27779. Benzeke at 16:54 PM on 6 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Digby, you are asking a very tough question.Time is not on your side for an easily recognized, opinion changing event to happen in the next few years.

       IMHO, the answer is: 'when Fox News says so'. I have floated the idea of a 'Fox News Moment', akin to the economic Minsky Moment. Or better yet, the 'Wile E. Coyote Moment' when he realizes he is about to fall to the bottom of the canyon. It is inevitable that the day will come when the ultra wealthy conservative class will realize that they have significant skin in the game and it is in their financial interest to change the agenda. Fox News will be the mechanism. I suspect a healthy number already understand this, but think denial is in their best interest, financially or politically. Cynical, but one reason they are rich is because they think this way. At some point, hopefully in the relatively near future, Fox will change its message.

       I think this will happen before there is any really obvious event that would change the minds of the rank and file denialists. The change will be framed in such a way that it does not compromise the current arguments. i suspect something along the lines of 'conservatives finally got the science right after the liberal, big science parasites screwed it up'.

       As for evidence a bit more tangible, I am afraid how hot is it now and where is sea level at the moment are all that will satisfy some people. Some will never acknowledge a change even if the water is lapping at their doorstep.

       Unfortunately the US east coast has been cooler than normal lately. Since 'how hot I am now' gets extrapolated to the whole world, a significant portion of the US is unaware that this is going to be a very hot year: it's been 123 in Basra, Iraq, but... it's Iraq.

       The 2011 La Nina brought Austin, Texas 99 days of 100 or higher, with 112 being the highest, and this was insufficient to convince Texans that the planet is warming. The previous record was 69 days of 100 or greater. I fear it will take Basra-like temperatures to convince Texans that we are messing with the planet. The next strong La Nina event is going to get interesting for Texas.

27780. Digby Scorgie at 14:28 PM on 6 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Tristan, I wouldn't want to confront their denial.  I'd like to get behind it.  If someone tells me global warming is a myth, another way I could perhaps achieve this is to ask "OK, I believe you (says he, lying in his teeth).  If global warming were really to occur, what would you expect to see?"

       I know that there are many people whose worldview excludes the possibility of global warming in our time.  I'd like to nudge them into thinking about a different world (like the PETM maximum) where global warming does occur.  So what if global warming does not occur in their world.  I'd like them to imagine a world where it does occur and then give me a description of it.

27781. ryland at 12:53 PM on 6 September 2015
       Climate change and Hurricane Katrina: what have we learned
       

       There is another side to the hurricane story that suggests natural variability has a significant effect on hurricanes and may play a bigger role than global warming.  Christopher Landsea, a scientist at the US NAtional Hurricane Center is not as certain as scientific organisations, such as the UK Royal Society and the US National Academies  of Sciences, that climate change is worsening hurricanes.  He considers hurricanes occur in cycles " "The late nineteenth century was a very busy period," he explains. "Then from the 1900s until about 1925, it was very quiet. The late 20s to the 60s were very busy. The 1970s to the mid-90s were quiet again, and then from the late 90s onward, it's been generally very busy.".  (http://tinyurl.com/pnqcdb3)

       The article gives a comprehensive discussion of hurricanes and expresses views some of which  do not entirely support those in the piece by Kerry Emanuel.

27782. Tom Curtis at 12:08 PM on 6 September 2015
       The cause of the greatest mass-extinctions of all? Pollution (Part 1)
       

       dudo39 @26, fairly obviously, a 1% CO2 concentration in respired air will result in an increase in pCO2 in the pulmonary system, and presumably also in the end-tidal CO2 concentration.  That the end-tidal CO2 concentration in breath is around 4% is therefore irrelevant to the result.  In other words, prolonged exposure to just 1% CO2 concentration is physiologically harmful to humans, if mildly so.

       Never-the-less, the concern about anthropogenic CO2 has nothing to do with direct physiological impacts.  It has to do with climate impacts, and the impacts of ocean acidification.  Discussion of physiological impacts (direct toxicity) is raised as a red herring by climate change deniers.  Even on the red herring, however, they get their facts wrong in that levels of CO2 concentration that could be reached in a determined BAU scenario do in fact have negative physiological impacts.  Not impacts worth considering given the other harms that would result from such a high CO2 concentration, but impacts none-the-less.

       Note:  the "background" CO2 concentration you refer to is the end-tidal CO2 concentration in respired air, ie, "the level of (partial pressure of) carbon dioxide released at end of expiration".  It represents the peak CO2 concentration in respired air, not the average concentration.  It is not even the average concentration in the alveoli, which start with a slightly lower level even durring expiration, and are likely to have a substantially lower level of CO2 at the end of inspiration, given that the inspired air has only the atmospheric concentration.

27783. Firgoose at 09:38 AM on 6 September 2015
       2015 SkS Weekly Digest #35
       

       Fixed wili's abbreviated link .. Positive tropical marine low-cloud cover feedback inferred from cloud-controlling factors

27784. dudo39 at 09:29 AM on 6 September 2015
       The cause of the greatest mass-extinctions of all? Pollution (Part 1)
       

       Rob Honeycutt @24,

       First lines of my comments 22 & 23 are "actual" questions.

       Tom Curtis @25,

       Thanks for the detailed information. I would then amend my implied statement that CO2 is not toxic, or pollutant, to humans in concentrations lower than about say 45,000 ppm.

       Does your statement "at sustained 1% CO2 concentrations humans buffer against CO2 by loss of bone mass" imply then that us humans  are undergoing loss of bone mass since birth [since it appears that  the background CO2 concentration in our lungs is about 4%]?

27785. Kiwiiano at 05:44 AM on 6 September 2015
       Climate change and Hurricane Katrina: what have we learned
       

       "such a horrendous prospect that otherwise intelligent people rebel against the idea even to the extent of denying the very existence of the risk."

       Whoa...the Christchurch city council is requiring new homes built near the sea to allow for future flooding with other mitigations and are at risk of being sued by outraged home-owners. The pity of it all is that they are pinning their colours to a very conservative sea-level rise estimate that is sure to be exceeded. 

27786. Tristan at 03:09 AM on 6 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Digby, the evidence they ask for can be put into one of three boxes:

       
       A) Can't realistically happen (temps tracking alongside Hansen's 1988 projection for Scenario A, which never occurred)

       B) WIll happen someday (statistically significant warming trend from both satellite datatsets from 1998+)

       C) Has already happened (evidence global warming is happening, is human caused, and is bad)

       
       In all cases, should evidence of any of those things occur, the committed denier will simply change their requirement, or find a reason why that evidence is unacceptable.

       This is not a unique feature of climate science denial, but relates to every sort of denial that exists.

27787. Tom Curtis at 15:31 PM on 5 September 2015
       Breathing contributes to CO2 buildup
       

       juan vicini @54 & 55:

       1)  The CO2 in soft drinks is obtained by capturing CO2 from power station exhaust, and then forcing it into the water under high pressure.  Because the CO2 is captured from power station exhaust, the amount of CO2 in that exhaust is reduced by the same amount as the CO2 "emitted" by soft drinks.  In consequence, soft drinks emit no CO2 that was not going to be emitted anyway.  It causes no increase in total CO2 emissions, other than that due to the energy of manufacture.

       2) All human food is either plant life, or processed from plant life (meats).  As such, the CO2 in all human food is obtained from the atmosphere by photosynthesis.  Further, once respired, new food is grown by again taking CO2 from the atmosphere by photosynthesis.  As such, the respired CO2 from humans does not increase overall atmospheric CO2 levels.  It is only possible to imagine that it does by ignoring the photosynthetic half of the equation.  This is all explained very clearly in the original post above, and in the comments afterwards.

27788. r.pauli at 13:51 PM on 5 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       the YouTube channel for Potholer54 has a wonderful playlist on denialists

       https://www.youtube.com/watch?v=52KLGqDSAjo&list=PL82yk73N8eoX-Xobr_TfHsWPfAIyI7VAP   

       "The main purpose of this channel is to explain in simple terms the conclusions of scientific research, and correct some of the unsourced crap we get fed on the Internet. I am a former science journalist (see the "Who I am" video) with a degree in geology."

       He is Peter Hadfield - I have enjoyed everything he has done. - https://en.wikipedia.org/wiki/Peter_Hadfield_(journalist)

27789. juan vicini at 13:36 PM on 5 September 2015
       Breathing contributes to CO2 buildup
       

       I wonder... How much of the CO2 in the atmosphere comes from soft drink bubbles?

27790. juan vicini at 13:27 PM on 5 September 2015
       Breathing contributes to CO2 buildup
       

       Humans sink Carbon through waste, Humans are producers by means of the increment in aricultural productivity per hectar which we have developed. Fossil fuel burning recycles sunk carbon like volcanoes do every so often. Humans are part of the biosphere increments in our population do increase co2 in the atmosphere through breathing alone. We do not produce all the food we eat, non farmed fish consumed by humans per year amounts to 70 million tons. the question of how much of the CO2 in the atmosphere comes from breathing is a valid one. in the end it is not just how much goes up and how much is sunk because we can't expect to keep earth on a permanent temperature indefinately as that would be imposible ue to prescesion of the earths axis. In fact trying to do o would probably harm the biosphere much more than fossil fuel burning. the adecuat balance of CO2 at any given moment in the atmosphere should be monitored as a percetage of total mas of living biosphere and in relation to the amount of C escaping the atmosphere aswell.

27791. Digby Scorgie at 12:37 PM on 5 September 2015
       Denial101x MOOC - Full list of videos and references at your fingertips
       

       Um, fellows, I don't think you understand my question.  If someone tells me global warming is a myth, I'd like to ask, "OK, so what would you say would be proper evidence of global warming?"

       I'm past the stage of caring what people think of climate change.  I doubt that any effective action will be taken in the near future.  It will be the planet that will change people's minds — and then it will be too late.

       Nevertheless, I'm still curious about how deniers would answer my question.  While there's curiosity, there's hope?!

27792. Daniel Bailey at 12:09 PM on 5 September 2015
       Spoiled ballots, spoiled views: an election snapshot from Powys, Wales, UK
       

       wideEyedPupil, given that I wrote the article you linked to, I'm not particularly worried about it. 

       

        

       1. The graphic you're interested in was taken from this source. 
       2. Nuclear power does have it's place, but as one of many wedges, and not the entire busload.
       3. But then, renewables can drive the busload by themselves, as it turns out.
27793. Tom Curtis at 08:11 AM on 5 September 2015
       Tracking the 2C Limit - July 2015
       

       ronald myers @43, HadCRUT4 has 30 years more data, but that data is drawn primarilly from Europe and North America meaning it is limited in extent, and geographically biased.  Because of this, NOAA and GISS decided not to included that data, considering estimates of GMST from that data to be too unreliable (a decision with which I agree).

27794. Tom Curtis at 08:05 AM on 5 September 2015
       The cause of the greatest mass-extinctions of all? Pollution (Part 1)
       

       dudo39 @23:

       1)  CO2 toxicity appears to be a complicated subject.  To begin with, the consequence of CO2 toxicity is not asphyxiation, which requires reducing oxygen concentrations to about 4%, but from increasing acidity in body tissues.  The effects of this increased acidity include hamorrhaging of lungs, spleen, intestines and kidneys.  It also includes loss of body mass, and the mass of various organs, although the rate of loss varies by organ and by species.  Finally, at 15% concentration, it results in the complete loss of spermatogenesis.  15% concentration sustained over several weeks also resulted in the deaths of 30 to 50% of guinea pigs, but not of rats.

       At lower levels of CO2, sustained exposure can be effectively buffered but at a cost.  Specifically, at sustained 1% CO2 concentrations humans buffer against CO2 by loss of bone mass.  This also is associated with replacement of calcium carbonate with calcium bicarbonate in bones as part of the buffering process.  I am not sure what effect this has on the strength or brittlness of bone.  The buffering is not continuous in time, but appears to go through stages.

       The upshot is that while humans cannot increase CO2 concentrations in the atmosphere to levels that are immediately fatal, or which will result in permanent sterillity (15%), at the upper limit we can increase atmospheric CO2 concentrations to levels that are toxic and have harmful effects on humans.  Other species, however, are far more susceptible to CO2 concentration, particularly some marine species.

       2)  Yes, atmospheric H2O is replaced by evaporation, but that just means the concentration of H2O is controlled by temperature.  Total human emissions of H2O does not increase the atmospheric concentration appreciably over the concentration due to that evaporation. 

27795. ronald myers at 07:27 AM on 5 September 2015
       Tracking the 2C Limit - July 2015
       

       My primary objective was to suggest changes to the first figure in this thread. There were three items. One was that HadCRUT4 has an additional 30 years of temperature record than GISS. The second item was a suggestion to adjust the CO2 so the average of the first 30 years are at 0 and consistent with the alignment of the temperature anomaly. The last was a method to include the CO2 concentrations on the figure and provide a means for the reader to determine the concentrations from the figure. You did bring up an additional suggestion to include other GHG concentrations and scale them in proportion to their forcing level. This would result in a total forcings line which is about 3% higher than just CO2 (based upon the natural log of the total forcing of 485 ppm CO2 equivalent per http://www.esrl.noaa.gov/gmd/aggi/aggi.html Table 2 and projecting 2015 value).

27796. Rob Honeycutt at 06:22 AM on 5 September 2015
       The cause of the greatest mass-extinctions of all? Pollution (Part 1)
       

       dudo39...  I can't see that you proposed any actual question(s).

27797. dudo39 at 01:42 AM on 5 September 2015
       The cause of the greatest mass-extinctions of all? Pollution (Part 1)
       

       To Moderator Response,

       Please tell me what policies did I not comply with?

       My comment about water vapor was in response to the satement "Water vapour quickly cycles back to the surface as rain".

       I did not suggest or imply that CO2 caused extinction by asphyxiation; my question was in response to "Harmful or poisonous effects depend on the physical and chemical properties of any one substance. Substances are widely variable in their toxicity in terms of concentration. Carbon dioxide, essential to photosynthetic plantlife, has other properties which, at higher concentrations, make it dangerous. As a strong greenhouse gas, any substantial increase in its atmospheric levels over a matter of a few centuries make it a pollutant because of the impacts of rapid climate change. At much higher levels it becomes an asphyxiant".

       Please note that National Safety Council's "Fundamentals of Industrial Hygiene" [4th Edition] states in the first paragraph in page 42: "Carbon dioxide is always present in the atmosphere, but the proporetion of carbon dioxide in air exhaled from the lungs is 100 times greater"; thus my statement about the 40,000 ppm of CO2.

27798. Jim Eager at 01:38 AM on 5 September 2015
       Global warming intensified the record floods in Texas and Oklahoma
       

       Umm, Denis, exactly where do you think those greenhouse gas emitting technological systems came from?  It was we humans who designed and built and use them. Trivial semantics aside, people have been making poor decisions that negatively impact the environment and thereby ourselves since long before we invented indusrialized civilization.

27799. Tom Dayton at 01:36 AM on 5 September 2015
       Hockey stick is broken
       

       David Appell is updating a list of all the hockey sticks anybody can find. He's asking for additions from anybody. It's over three dozen now.

27800. wideEyedPupil at 01:32 AM on 5 September 2015
       Spoiled ballots, spoiled views: an election snapshot from Powys, Wales, UK
       

       @Daniel Bailey 28
       You might be aware you first graph comparing avain death by power source ahs been reused various places online like here. I'm wondering where the source for death by nuclear came from. Nuclear advocates often level this myth about wind turbines and it would be nice to have a reliable source to say well, if it's bird deaths your care so much about then you'd advocate replacing nuclear with wind power. Thx Alastair

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