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Comments 26651 to 26700:

26651. bozzza at 13:46 PM on 18 November 2015
       The thermometer needle and the damage done
       

       Sequestration makes zero sense: ..as it, too, is subject to the same Jevons Paradox as the fossil fuels it seeks to make more efficient in the first place. 

       It's like a dog chasing its tail: only the most anti-intellectual of societys could still be stuck on this as if it were a problem...that's what the goggle-box 'll do to ya!!!

26652. Tom Curtis at 13:40 PM on 18 November 2015
       Exxon climate revelations are just part of a long history of science misinformation
       

       ryland @6, the NSW government has a policy of replacing a planning framework that takes IPCC projected sea level rises into account using a single value for the entire state with one that takes into account IPCC projected sea level rises but allows variation across local government areas based on differences in sedimentation and erosion, subsidence and uplift and (presumably) the fact that sea level rise is partially abated as you move northward (and exagerated as you move south ward) due to uplift in northern regions related to the colission of the Australian continental plate with that of Asia.  You glossed that as "NSW government is advising councils to no longer follow the predictions of the IPCC" even though no such statement was made by the NSW government, the minister or any of the spokepeople, and indeed the minister has made statements directly contradicting that delusion.  That is your fantasy.

       You have additional fantasy's evident above in your belief that not only are their people who think "they are subject to misinformation campaigns" by people reporting the findings of the IPCC, but you think they are rational in that assessment.  In fact such people are delusional on a conspiracy theorist level - something quite evident from the facts that:

       a)  They in fact subscribe to a conspiracy theory with regard to the findings of the IPCC; and

       b)  They appear untroubled by the even more delusional conspiracy theories from the likes of Christopher Monckton.

26653. Andy Skuce at 13:35 PM on 18 November 2015
       The thermometer needle and the damage done
       

       No, these researchers did not look at the problem from that angle. I would expect that any proceeds from a carbon tax levied in any country and would be spent within that country, either by reducing other taxes or by increased government spending. So, there shouldn't be that big of a direct hit from a carbon tax. Nevertheless, even rich countries will endure some strains from carbon taxation, since there will be winners and losers, as well as adjustment pain.

       But on the whole, the rich will be able to deal with carbon taxes better, even if they have to pay more, simply because they can afford more options to avoid them. 

26654. Andy Skuce at 13:26 PM on 18 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       Meurig: there are several other sequestration methods, biochar among them, that I didn't attempt to cover here. Others would be mineral sequestration (olivine or basalts) and various forms of sequestration in the sea by iron fertilization or pumping CO2 into the ocean depths. All of these methods are even more speculative and untried than geosequestration. Some of them are hard to scale, some don't offer a permanent store and some might just be too expensive to deploy.

       That doesn't mean that I would necessarily write these technologies off, just that making them a big part of a mitigation scenario now would be premature. The main point I was trying to make here is that, if you rely on sequestration as the main response to the climate crisis, you are facing a gigantic problem no matter what technology you employ. 

26655. scaddenp at 12:01 PM on 18 November 2015
       Exxon climate revelations are just part of a long history of science misinformation
       

       "Or it is fantasy to state that a considerable and significant prercentage of the global population is not convinced that climate change is due only to human activities?"

       It might not be a fantasy, but AGW is a fact whether it suits people to believe in it not. Similarly it is also absurb for policy-makers not to base policy on scientific consensus especially when it is strong.

26656. ryland at 10:47 AM on 18 November 2015
       Exxon climate revelations are just part of a long history of science misinformation
       

       Tom Curtis  I am well aware of your disdain but what I wrote was not fantasy but fact substantiated by appropriate references.  Are you saying thr comment by Mr Stokes that the draft regulations "recognise that the coastline is dynamic and ever-changing, rather than static" is fantasy? Or is it fantasy that the goverment is intent on changing the existing criteria, that are based on IPCC predictions, for assessing coastal development  Or that the emails to which I referred are fantasy?  Or it is fantasy to state that a considerable and significant prercentage  of the global population is not convinced that climate change is due only to human activities?  Or is there some other statement of mine that you regard as fantasy?   

26657. baeb at 09:41 AM on 18 November 2015
       The thermometer needle and the damage done
       

       I'm wondering if the economists that predicted that hotter poorer nations will have the most problem with global warming were taking account of the probable fact that richer less warm nations are more dependent on abundant fossil fuel energy for their survival?  Thus say, if eventually there is a huge carbon tax and not very cheap renewables to replace it, might not rich nations take a bigger hit than poorer ones where perhaps people are more self-sufficient and produce more of their own goods because they can't afford not to?

26658. meurig at 08:39 AM on 18 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       It would be good to see a treatment of the potential for carbon sequestration through sustainable biomass pyrolysis + addition of biochar to soil.  It doesn't look like an inexpensive option, and it won't necessarily work everywhere - but the same is true of BECCS.

26659. Tom Curtis at 07:21 AM on 18 November 2015
       Climate's changed before
       

       MA Rodger @514, yeah.  Finding an appropriate 20th century instrumental record for comparison can be tricky.  In this graph, from the IPCC AR5 (Fig 5.7), they use respectively, HadCRUT4 NH and HadCRUT4 extratropics (30 N plus), HadCRUT4 SH, and HadCRUT4 Global for each each of the three appropriate panels.  For what it is worth, the pre-twentieth century global temperature range is 0.8 C for Man EIV 08 (the reconstruction with the largest range.  That compares to a peak range of 2.02 C in the upper panel (NH) spaghetti graph.  That, however, is for a NH extratropics (30-90), land only reconstruction by Christiansen and Lungqvist (2012).  Both the latitude range and land only features would again exagerate temperature variability if the reconstruction were misinterpretted as a global reconstruction. 

       

       PAGES 2000 show a 0.6 C variation for global temperatures using 30 year bins.  That later feature will supress the full range of variability, but the result is consistent with Mann 08.

       Given this, and that the temperature range from 1880-1910 to current is about 1 C, it is evident that 20th century plus temperatures have already exceded the maximum range of global temperature variation in the 1900 years pre 1900 AD, and by about 20-25%.  Further, it has done so in just over a century, whereas the maximum temperature range pre 1900 (for the last 2 K years) is spaced by about 400-600 years.

26660. MA Rodger at 06:02 AM on 18 November 2015
       Climate's changed before
       

       Tom Curtis @513.

       Indeed. The 1.7°C was a mistake that dodged being edited.

       My own take on the spread of data in the Loehle & McCulloch (2008) reconstruction was that almost 60% of it is either North Atlantic or close by there. I did half think that representative thermometer records could be sourced from the GISTEMP or BEST websites as both have 'clicky' maps that yield the nearby stations. That would then allow some attempt of comparing oranges with oranges. Then I reasoned, the strong 1930s warming in the US & Arctic Atlantic will probably prevent the extra warming since 1935 shooting too far off the graph. Thus my choice of global GISTEMP to bring the reconstruction up-to-date.

26661. Tom Curtis at 01:47 AM on 18 November 2015
       Climate's changed before
       

       MA Rodger @512, NN1953VAN-CA actually cites a 1.3 C temperature variation (from -0.8 to +0.5 C).  Even that is incorrect, however.  The actual temperature range for the mean value is -0.6 to 0.56 C, for a 1.16 C temperature range.  

       Even that is exagerated taken as a global value.   That is because, of 18 proxies used, Loehle and McCulloch use 12 from the NH extratropics, 4 from the tropics, and 2 from the SH extratropics.  As they take a simple mean of the proxies, they tacitly assume that 66.7% of the Earths Surface is in the NH extratropics, 22.2% in the tropics, and just 11.1% in the SH extratropics.  The real values are 30.11% NH extratropics, 39.78% tropics, and 30.11% extratropics.  Even within zones, the data is heavilly biased, with 8 of the 12 NH extratropical proxies coming from the North Atlantic Region (Europe and North America) and the rest from China, the tropical proxies coming from Indonesia and Africa, with South America excluded, and all SH proxies coming from Africa.

       These biases matter.  The NH varies more in temperature because of the greater percentage of land in the NH.  The North Atlantic is known to be the region of greatest and most persistent temperature change due to the so called Medieval Warm Period.  So not only are the proxies heavilly biased in coverage, the are biased in favour of areas known to have greater temperature variation before the proxies were chosen. 

       That bias extends to the fact that only 8 of 18 proxies (44.4%) are for SST, despite 70.8% of the surface being ocean.  This strong terrestial bias again distorts the result given that temperature changes over land are greater than those at sea.  (Odd how every bias in the data exagerates temperature variability.)  Unfortunately, SST proxies are limited in number, and this particular bias is not atypical of paleo temperature reconstructions.  That, however, means in turn that although error bars tend to be shown as symetrical for such reconstructions, in fact the reconstructions are more likely to exagerate variability than supress it.

       Moderator Response:

       [PS] I note that NN1953VAN-CA is using the badly flawed reconstruction of Loehle, (published in the "tobacco science of climate" journal E&E) rather than something like Ljungqvist 2010 from the peer-reviewed literature.

26662. MA Rodger at 22:08 PM on 17 November 2015
       Climate's changed before
       

       NN1953VAN-CA @510.

       I assume you mean to say that the poles vary the more and not "with least temperature change". Similarly, individual locations will vary more than a global mean. (You cite the 1.7°C wobbles of the 2,000 year Loehle & McCulloch (2008) temperature reconstruction. The individual proxy data varies by 7.5°C.)

       The graph you present of recent met. measurements at Vostok shows a trend (or lack of trend) for temperature not for temperature anomaly. If you examine the other graphs available on the site (you link to @510), you will see the individual months (which do not require converting into anomalies) show significant trends in temperature. The annual average data (again which doesn't need converting into an anomaly) gives a trend of 0.017ºC/y. This is not large compared with the global average but no single point on the globe can be expected to behave as the global average does. Do examine that "spaghettigram" of data used in Loehle & McCulloch (2008).

       Perhaps the most important point you miss is that the Loehe & McCulloch (2008) graph you present only shows data to 1935. The 'decline' prevents the use of more recent proxy data. If you then splice on, say, GISTEMPS data, the reconstruction would sit at +0.825ºC using 10-year rolling averages (and +0.98ºC using rolling 12-month averages). This rise, unprecidented in the rest of the reconstruction, is AGW.

       Your calculation of the effect of CO2 forcings on global temperatures is far too crude. A 40% increase in CO2 should eventually increase global temperture by roughly 1.2ºC after the forcing has been balanced by temperature, something which is a long way off as the CO2 has been present only a short time. (Also, it is not just CO2 that is resulting in AGW.)

       Discussion of the benign climatic results of AGW that will indeed be evident in some parts of the world are off-topic here. However, as you are happy to make some places less habitable for many millenia, perhaps you should invite a few Nigerians, Indians Indonesians etc (who even now are suffering from elevated temperatures in an already hot climate) to come and live with you. I would go further than Eclectic @511. The view "you are pushing" is denying something potentially far far worse than WWII.

26663. Eclectic at 21:51 PM on 17 November 2015
       Climate's changed before
       

       NN1953VAN, you seem "stuck" on Vostok. Taking far too much stock of Vostok, so to speak :-)

       As Tom Curtis has said, that's a regional record. And you seem to be concentrating on one or two regional trees . . . and you are ignoring the forest of evidence which torpedoes the case you are trying to argue.

       In addition, you are wrong in your total assessment (of total human agriculture etcetera) of the outcome of present day global warming ~ please see: under the thread of "It's Not Bad", and elsewhere ~ how world agricutural output will reduce as surface temperatures rise further. [ If you care to educate yourself on the matter, then you will find multiple reasons for that deterioration. ]

       And you should also "factor in" some extensive political and social disruptions from mass migration of "climate refugees" . . . and here, if you think today's Europe is managing poorly the influx of refugees . . . well, you (and Europe) ain't seen nuthin' yet ! Yes, Canada's and Russia's soils  will benefit somewhat from higher temperatures ~ but those countries won't enjoy the accompanying socio-political burdens.

       Will the world [in your words] "get back on it's own as it has many times before"? . . . well indeed, it might well do so in 10,000 or 100,000 years. But to be relaxed about that (distant) prospect, is like being relaxed about the deaths and miseries of World War II . . . which count as a pinprick [by your line of argument] because that war was insignificant in length ~ a mere 6 years [1939-1945]. Yet that is the view you seem to be pushing.

26664. ranyl at 20:20 PM on 17 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       "480 CO2e…

       Unfortunately, the global CO2 measure doesn’t tell quite the entire story. For atmospheric levels of gasses like methane, nitrous oxide, and a host of less common industrial chemicals have also all been on the rise in Earth’s atmosphere due to human emissions. As a result, according to research by the Advanced Global Atmospheric Gasses Center at MIT, total heat forcing equal to CO2 when all the other gasses were added in was about 478 ppm CO2e during the spring of 2013. Adding in the high-velocity human greenhouse gas contributions since that time gets us to around 480 ppm CO2e value. In the context of past climates and of near and long term climate changes due to human interference, 480 ppm CO2e is nothing short of fearsome."

       http://robertscribbler.com/tag/480-ppm-co2e/

       Yet the 2.6RCP in Figue 1 (Fuss) gets to max 480CO2e by 2100 with another 50 years of net positive emissions, those negative emissions must be huge to clear it allotu agaim in 20years, yet they look quite small....makes you wonder about the realism here??

       And as there is growing evidence that the climate sensitivity more likely to be between 3C-4.5C, is it possible that these predicted temperature range % chances will be too low due to including models with unrealistically low climate sensitivities (<3C)?

       Maybe a better way to consider the CO2 levels needed is to consult the past as the primary measure?

       Last time the CO2 was 400-450ppm, the world was 4-6C hotter, and sea levels 30-40m higher in the Miocene?

       300ppm average is ~current temperature when this record breaking 2015 El NIno fully matures and sea levels 6-9m higher back then, and weare well above this 300ppm and have put the CO2 in incredibly fast (faster than seen in geological records so far).

       Can't help feeling as the resulting heat input will presumeably also be faster than has occured previously as well that melt rates could exceed previous records and many expectations?

       400-450ppm means eventual 30-40m over the next millenia, but that rate must depend on heat rate input as well, and previously 4-5m a century have occured in Ice sheets melts.

       Even 1-2m means moving potentially having to move some major coastal cities and that 1-2m seems highly likely by 2100 even if stopped all emissions today and things went immediately carbon negative.

       War apparently causes massive amounts of CO2 emissions and ecosystem devastation.

       This is not factored into the CO2 emissions scenarios though (we have plenty of war though), and additional CO2 emissions from war induced ecosystem dessimations aren't either, nor permafrsot melt, nor peat burning in Indonesia, nor forest fires, nor the reductions in CO2 fertilisations as nutrients decline, species are foresd to shift climatic zones and drought and rain become unprecedented.

       BECCs impacts on ecosystems probably aren't factored in either and presume biomass growth consistency using industrial know how, and thus widespread environmental impacts (pesticides, fertilizes etc).

       300ppm seems safe...ish?, that is eventual sea level rise of 6-9m and temperature between current and 2C as the final outcome.

       Is 300ppm CO2e by 2100 impossible?

       And what does the reasonably possible 2m by 2100 sea levels rise actually mean for places New York in less than a century's time?

       Remember to add in the storm induced sea surge growth as well?

26665. Andy Skuce at 18:21 PM on 17 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       Tom Curtis provided a nice explainer on the drop in atmospheric oxygen in his Climate Change Cluedo post, part 6 It includes this IPCC diagram, which I find very useful. See Tom's text for a very clear explanation.

       

26666. NN1953VAN-CA at 16:35 PM on 17 November 2015
       Climate's changed before
       

       Few centuries or even millennia observation may not give real trend in global climate, as there were abrupt changes after long steady trend. My point is that CO2 does not affect climate change in measure some are trying to prove.

       Looking at Atmospheric CO2 content in time span of several centuries:
       CO2 stable for several thousand years at 250 – 280 ppm
       Vostok and Gereenland are the places with least temperature change expected. (I am aware it’s not global). When mentioned ‘least temperature change’ at any time and for any given period temperature variation day/night on equator or seasonal on mid latitudes varies much more than on polar regions, again, averages do not change much on either.
       Vostok temperature varied 3 degrees with CO2 content stable, and in last 60 years with CO2 gone to 400 ppm (looking at 280 ppm it is 40% increase) temperature is stable. Please see table.

       Vostok station

       Vostok surface temp
       
       This is recent average surface temperature at Vostok – there is lack of data for 1962,1964, 1996, and 2004 other than that there is no temperature increase.
       Next graphs are for Greenland:

       

        

       
       Please check top graph – right side from 1950 to 20xx
       Atmospheric CO2 gradually raised to 400 and at same time span Greenland temp. varries, but doesn’t follow CO2 trend.

       Global temperature reconstruction done by Loehle, 2007 and Loehle and McCulloch, 2008 studies

       

       Average temperature change from +0.5 to -0.8, does not follow CO2 content which is stable until 1950.
       Yes, there are other forcing but somehow all other forcing are overcoming CO2 is at present level as there should be much greater GT change for 40% CO2 increase. If so, which other forcing works now and was not present when CO2 was stable and temperature rose. Because if ‘other forcing’ are preventing temperature raise, it means CO2 GHG effect is not that great as GHG theory is trying to show.
       Recent GT should reflect higher upward trend if CO2 is 25% of GHG effect, and risen for 40%.
       Beside, GW is not that bad, there are parts of the world which would greatly benefit from some temperature raise, e.g. great part of north hemisphere presently uninhabitable is going to be much more humans friendly. Of course there are just as many parts of planet which will become uninhabitable or under the sea. It will get back on it's own as it has times before.

26667. Rolf Jander at 15:58 PM on 17 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       Daneil: Thanks for the reasuring numbers but it is still creepy.

       scaddenp: That was kind of my point, the co2 we made would eventually come back as oxygen if we stop burning FF. Heres hoping we get on that sooner rather than later.

26668. scaddenp at 13:57 PM on 17 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       Yes, and thanks to the wonders of photosynthesis, so long as we have CO2 in the atmosphere, we will also have O2.

26669. Daniel Bailey at 13:50 PM on 17 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       "for every atom of carbon locked away we lose two atoms of oxygen"

       No need to panic:

       "We are occasionally reminded that fossil fuel burning is depleting atmospheric oxygen at a rate of almost 1000 tons per second. There are about 32 million seconds in a year, so that somewhere around 30 billion tons of O2 are being converted to CO2 annually. There are about 1,200,000 billion metric tons of O2 in the atmosphere, so we can keep burning fossil fuels at the present rate for 40,000 years before we run out of oxygen. By then, all of the world's fossil fuel supply will have long since been exhausted. For a more complete, but less detailed, discussion of this topic see Et tu 02 by Wallace Broecker.

       If we take the worlds supply of fossil fuel to be 10,000 billion metric tons of carbon, as per [LINK] and we oxidize all of it we would get about 37,000 billion metric tons of CO2, and about 27,000 billion metric tons of O2 would have been consumed. Some additional O2 would have also been consumed by oxidation of hydrogen in the (hydrocarbon) fuel, so that roughly 38,000 billion metric tons of oxygen would have been consumed. This is about 3.3 percent of the atmosphere's oxygen. Such a loss would be equivalent to increasing your elevation from sea level to about 330 meters, or about 1100 feet."

       Emphasis added.

       SOURCE

26670. Rolf Jander at 13:27 PM on 17 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       CCS worries me. for every atom of carbon locked away we lose two atoms of oxygen. It depletes the atmosphere in general as well. I can't help but think the cure might be worse than the disease, like the little old lady who swallowed the fly. I would hope instead that using graphene enhanced solar cells batteries and capacitors, renewable energy will deploy rapidly and avoid this drastic soloution.

26671. Tom Curtis at 12:56 PM on 17 November 2015
       Exxon climate revelations are just part of a long history of science misinformation
       

       CBDunkerson @3, the NSW Coastal Planning Guideline that is being superceded is this one, implemented under the previous Labor government in 2010.  The discontent by developers over the Guideline was a requirement that councils take into account the benchmark for sea level rise of "... an increase above 1990 mean sea levels of 40cm by 2050 and 90cm by 2100."  It also required councils to advise developers on present and future hazards.  The Liberal/National Coalition government that superceded it in March 2011, and modified the Guidline with a circular to councils.  That made, as near as I can tell, the reporting of future hazards optional for councils, and required that any future hazards be identified as future hazards.  Thus the change is that, under the first policy the reporting of future hazards was mandatory, while it was optional that they be identified as future hazards; while under the policy as of 2012 (ie, the issuance of the circular) the reverse was true.

       The current change to the policy, under the Baird Liberal/National Coalition government will require that greater account be taken of local conditions.  It does not challenge the benchmark of sea level rise, nor dispute it.  Indeed, under the O'Farrell L/NP govenment, the NSW Chief Scientist issued a report those benchmarks, saying:

       "In considering the science behind sea level rise benchmarks, the one constant that emerges
       is change. The way the science has been used to determine benchmarks is adequate, given
       the current level of knowledge. However, for some years to come there will be more and
       better models for predicting sea level rise which will be informed by more and better data
       enabled by rapid advances in sensing, positioning, computational and imaging technologies."

       and:

       "In 2009 the then NSW Government developed two benchmarks - for 2050 and 2100 sea
       level rise. Overall, the approach was one whereby projections for global sea levels at the
       middle and end of the 21st century were added to other more regional estimates for these
       time periods, as well as a global accelerated ice melt factor. This methodology is similar to
       that used in other jurisdictions in Australia and around the world, with some international
       jurisdictions utilising more extreme climate modelling approaches to explore possible worst
       case scenarios."

       Despite Ryland's fantasies, there is no indication that the review will reduce expectations of sea level rise built into the new benchmarks.  Indeed, given that the old benchmark was based on the IPCC TAR (2001), it is more likely that they will increase that expectation.  What it will do is make allowance for locations like Newcastle, where due to ongoing subsidance the local effective rise in sea level is likely to be larger than that indicated by the benchmark, while also allowing that for some other locations in NSW, they may also be slightly less.

       It is only denier politicians and media playing this up as a rejection of IPCC predictions.  In fact, and because it is purported to be science based, it is nothing of the sort.

26672. Digby Scorgie at 10:39 AM on 17 November 2015
       The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy
       

       I'm not sure it's valid to consider RCP scenarios without also considering the effect of the increasing world population and our decreasing ability to feed everyone — an ability that is being increasingly compromised by climate change.  Optimistic statements to the contrary, it seems from all I've read on the subject that we'll reach a tipping point in the near future.  At this point a lot of people will die of starvation and strife.

       How is CCS going to prevent such a catastrophe?  The graph shows CCS increasing from about 2030 to 2040 onwards.  That's exactly the time when the aforementioned tipping point is likely to occur.  In other words, it will be too late.

26673. Tom Curtis at 10:02 AM on 17 November 2015
       2015 SkS Weekly Digest #46
       

       RobH @1, from page 10 of the Pew Article, we find the number of respondents by discipline:

       

       Running the percentages, that is 49.5% from biological or medical, 13.7% from chemistry, 6.1% from geosciences, and 9% from physics and astronomy.  From the first table on page 3 we find that 497, or 19.6% are in some other discipline, with 50 not responding to this question.  Further, from first table on page 3, only 66% of respondents were actively involved in research.  From those figures it is uncertain how many of those surveyed were actual climate scientists but it was certainly significantly less than 50%.  Further, around 50% are from a discipline from which we would not expect any significant background knowledge to assist in understanding climate science.

       These results are very similar to the Doran (2009) survey of Earth Scientists, of which 8.5% of 3,146 respondents published on climatology, 5% were climatologists, and 2.5% where climatologists actively publishing on climatology.  Doran (2009) showed the following results on the attribution question:

        

       That shows an 88% 'consensus' among active publishers on all topics (ie, actual research scientists) when restricted to earth scientists only, but only a 76% 'consensus' among nonpublishing, non climatoligists.  Famously it found a 97% consensus among actively publishing climatologists on attribution.  That is, as expertise declines as measured by either discipline, or area of research so does confidence in the consensus on attribution - but among those who are most expert as measured by both discipline and research activity, there is a 97% consensus.  The results of the 2009 Pew survey of scientists are quite consistent with this.

       While on the topic, the actual climate change questions in the survey were:

       "Which of these three statements about the earth’s temperature comes closest to your view?
       1 The earth is not getting warmer

       2 The earth is getting warmer mostly because of natural changes in the atmosphere [OR]
       3 The earth is getting warmer mostly because of human activity such as burning fossil fuels
       9 Don’t know/Refused"

       and

       "In your view, is global warming a very serious problem, somewhat serious, not too serious, or not a problem?

       1 Very serious
       2 Somewhat serious
       3 Not too serious
       4 Not a problem
       9 Don’t know/Refused"

       There is no ambituity in these questions on which the deniers can play their typical word games to avoid the results of a survey - though no doubt they will try.

26674. bibasir at 02:56 AM on 17 November 2015
       Exxon climate revelations are just part of a long history of science misinformation
       

       The New York Times article referenced below details how Exxon's own research in 1995 concluded CO2 emissions were causing global waarming.  The link still works.

       http://www.nytimes.com/2009/04/24/science/earth/24deny.html

       “Back in the 90s, the Global Climate Coalition, led by ExxonMobil, did fund scientists to determine the cause of global warming. GCC’s own scientists concluded that human emissions of GHGs were responsible so they promptly squelched that report and began funding front groups to deny the science and to confuse the public.

       But a document filed in a federal lawsuit demonstrates that even as the coalition worked to sway opinion, its own scientific and technical experts were advising that the science backing the role of greenhouse gases in global warming could not be refuted.”

       “The scientific basis for the Greenhouse Effect and the potential impact of human emissions of greenhouse gases such as CO2 on climate is well established and cannot be denied,” the experts wrote in an internal report compiled for the coalition in 1995.

       Moderator Response:

       [PS] Fixed link

26675. wili at 01:36 AM on 17 November 2015
       2015 SkS Weekly News Roundup #46
       

       For the next news roundup?

       According to the JMA, October 2015 (+0.53C) is a new record, beating the record set last year by whopping +0.19C. This makes is just the second month on record, and second month in row, with an anomaly of at least +0.5C above the 81-10 average. This is now also the largest anomaly for any month on record.
       
       

       ds.data.jma.go.jp/tcc/tcc/products/gwp/temp/oct_wld.html

26676. Joel_Huberman at 01:25 AM on 17 November 2015
       G R A P H E N E
       

       I want to reinforce the comment of Mark Welsch @15. There's no need to wait until graphene is commercialized. In some locations, renewable energy with current technology (wind, solar) is already better than fossil-fuel energy in terms of price. With a gentle push from a steadily rising fee on fossil fuels, based on their CO₂ emissions, and with all of the fee revenue (minus a few percent for administration) being returned to legal residents on a per capita basis to cushion against the rising price of energy, renewable energy will gradually become the superior energy choice throughout the world. By joining and working with Citizens' Climate Lobby (CCL), everyone reading this post can contribute to this essential acceleration of the transition away from fossil fuels. Since I joined CCL last April, I've been increasingly impressed by the quality and effectiveness of its work. It's a non-partisan, international organization that, in the United States, works constructively with both Republicans and Democrats. I'm optimistic that it will succeed in getting "carbon fee and dividend" legislation passed in the United States, even in a Republican-dominated Congress, within the next few year. By joining and working with CCL, you can help accelerate this process.

26677. RobH at 00:13 AM on 17 November 2015
       2015 SkS Weekly Digest #46
       

       Good Grief! Who are the 3 to 16% of global scientific community who dont accept that humans are causing climate change?

26678. CBDunkerson at 22:53 PM on 16 November 2015
       Exxon climate revelations are just part of a long history of science misinformation
       

       ryland, what "for-hire think tanks" do you believe "proponents of AGW" employed? NASA?

       What industry do you believe has been 'funding a public misinformation' campaign to promote the existence of global warming? Where is your evidence of the big payments this group (the Illuminati?) has made to Fourier, Tyndall, Arrhenius, Callendar, Keeling, and other scientists who have been building this 'false story' for the past 200 years?

       As to NSW, the article you linked requires a site-subscription to view, but others on the subject quote the same man as saying, "Changes to climate are likely to intensify our existing hazards", and give the impression that what he is advocating (and it is apparently being hotly disputed, rather than the settled government policy you suggest) is a change to  local beach maintenance regulations from the 70s - rather than anything to do with the IPCC at all. Which makes sense, given that the IPCC reports don't even have that kind of district planning guidance in them. Basically, it looks like you have just fallen for yet more propaganda... frauds recasting an announcement about local government organizational minutiae into a slam on the IPCC.

26679. Eclectic at 20:26 PM on 16 November 2015
       Exxon climate revelations are just part of a long history of science misinformation
       

       Not quite sure what point you are aiming to make there, Ryland @ #1.

       If you are stating that promoting a lie is no better or worse than promoting truth . . . then you are simply being absurd. If you are stating that knowingly promoting a lie is no better or worse than unwittingly promoting a lie . . . then you are simply being absurd, also.

       For a quarter-century or more, there has been "nowhere to hide" for the climate-science deniers who would wish sincerely to consider their viewpoint somehow valid. And even a half-century or more, for the tobacco-science deniers.

       Being duped by propaganda is a separate matter ~ but nobody is seriously suggesting that it is the "dupes" who are deliberately funding the science-denying propaganda.

26680. ryland at 20:14 PM on 16 November 2015
       Exxon climate revelations are just part of a long history of science misinformation
       

       My apologies for not putting this snippet of news in the above post but I have only just become aware of it.  It appears the NSW government is advising councils to no longer follow the predictions of the IPCC on climate change and sea level rise when considering applications for building.  The Planning Minister has advised he will be announcing  “a much more scientific and evidence-based ­approach … it reflects recognition that what is happening on the coast is a product of what is happening to the sand off the coast,” he said.

       “We will be integrating coastal management and planning with what is happening in the adjacent seabed.”   The reference is here.  

       It will be interesting to see if similar changes to other IPCC predictions result in changes in the public viewpoint.

       Moderator Response:

       [JH] Here is Ryland's "above post". I deleted it by mistake. My apologies to Ryland and everyone else reading this thread. 

       Mr Cook, you make this comment with regard to the Tobacco and Fossil Fuel industries:

       "Both had excellent lobbyists. Both employed front groups and for-hire think tanks as those grew in the 1990s. Both used whatever media were available, starting with print and radio, and now the Internet".

       Isn't this exactly what the proponents of AGW also do to get the message across?  Isn't it rather hypocritical  to condemn the tobacco and fossil fuel industries for doing what the IPCC and sites like this also do?

       In fairness, you do go on to say "Both funded public misinformation campaigns long after their own scientists had discovered the truth".  There are many outside the community of climate scientists, who, while perfectly sure climate change is happening, are not convinced humans are as much to blame as is suggested by politicians and climate scientists.  See examples here and here. These people may well be and from their comments indeed are,  of the opinion that they are subject to "public misinformation campaigns"  and that the truth has yet to be discovered

26681. Tom Curtis at 12:43 PM on 16 November 2015
       Why were the ancient oceans favorable to marine life when atmospheric carbon dioxide was higher than today?
       

       bozza @3, geological events are not timed based on "acceptable error values".  They are timed using the means available to as high an accuracy as is technically feasible.  Errors in the hundreds of thousands of years in the mid phanerozoic are achievable in some circumstances (example), and of one to three million years in many circumstances (example).

       Further, uncletimrob's claim that dating uncertainty makes answering the question in the OP's title impossible is simply false.  First, the answer has been given by detailed computer modelling as shown in Fig 3.  Second, the answer has been confirmed by a large number of emperical studies where relative dating based on stratigraphy is sufficient to distinguish later from earlier times and provide an answer, even if precise absolute dating is impossible.

26682. bozzza at 00:40 AM on 16 November 2015
       Why were the ancient oceans favorable to marine life when atmospheric carbon dioxide was higher than today?
       

       ...by definition the error is atleast tens of millions of years assuming an acceptable error value of +/- 5%!

26683. bozzza at 00:28 AM on 16 November 2015
       Video: Drought, Climate, Security, and Syria
       

       @1,

        The difference between 'direct' and 'indirect' causation is not as big as the language might have you believe.

        Words do not contain the truth according to some interpretations of eastern scriptures... suffice to say:  when Bruce Lee narrated that when he points at the moon he also narrated that you and all others concerned should not look at his finger or you will miss all the heavenly glory!!!

26684. braintic at 22:47 PM on 15 November 2015
       CO2 effect is saturated
       

       Rob Honeycutt:

       Mike Sanicola is Morgan Wright. He runs the Hyzer Creek Disk Golf course in New York. His YouTube ID is hyzercreek. "Mike Sanicola" is actually the name of a baseballer who was drafted to the Yankees in 1983, was seriously injured, then went into the ministry.

       As Morgan Wright, he claims to be an optometrist. In his most recent YouTube comments, he made the mistake of mixing the two identities, which tipped me off to the Sanicola identity.

       He says "I'm an opticist, who specializes in optics and IR. I worked for GE's infrared department and designed infrared telescopes for GE that were used by NASA in outer space.  I invented the ambient temperature microbolometer."

       Also, no proof yet, but I am beginning to wonder if he is actually Steven Goddard. He regularly links to Goddard's site, and their manner of speech and desire to advertise dual occupations are eerily similar.

26685. chriskoz at 10:26 AM on 15 November 2015
       Video: Drought, Climate, Security, and Syria
       

       michael sweet@3,

       Sport is entertainment while AGW is a battle for survival in increasingly hostile environment. So different situations are and so different moods in them, that the same subjective perceptions (as you would imagine) will never apply.

       In an entertainemnt, the culprit is saught because the good time was "spioled".

       In a battle for survival, a denial (sometimes deep rooted) is the first and someimtes only response, from both victims and vested interests causing it. Also note that as AGW is a major cause of war in Syria, the media try to ignore that link (denial at that level), instead trying to inflate the attribution of other causes: religious conflicts, military intervention by West, etc.

26686. shoyemore at 01:48 AM on 15 November 2015
       Video: Drought, Climate, Security, and Syria
       

       Another good analogy I read is the role of speed in motor accidents.

       Speed (driving faster than the conditions warrant) may not directly cause road fatalitities, but it reduces the options, increases the risks and makes deaths or serious injuries more likely. A "threat multiplier", in other words, much like climate change and geopolitics.

26687. MA Rodger at 23:03 PM on 14 November 2015
       Climate's changed before
       

       NN1953VAN-CA @508.

       Your observation that there have been large variations in temperature as reconstructed by the Vostock ice core data does not contradict "GHG theory". You point to a 3.17°C variation over the 163 year period 397-234ybp within that Vostock data. And if you examine the GISP2 data, there are variations of a similar scale, for instance a 3.7°C variation over a 393 year period.

       As Tom Curtis @507 pointed out, a single location will show greater variation in temperature than will a global average. And the poles will be the places where such local variations are expected to be the greatest. Also mentioned @507, the graph shown @507 does contain the Vostock and GISP2 data but the data are strongly smoothed so only longer-lasting wobbles will appear at full size.

       Sadly the different shades of blue used in the graph @507 are not particularly clear. In the graph, Vostock is one of the two dark blue traces. Your -3.17°C variation being a very sudden variation (the preceeding 155 years show a +2.9°C variation and the following 44 years a +2.2°C variation), it is dramatically smoothed out in the graph and appears as a dip of -0.2°C. GISP2 is one of the light blue traces and for the most recent millenium it is the bottom trace on the graph. The GISP2 data contains variations that are far less sudden than with Vostock so less of the GISP2 wobbles are smoothed out.

       But let us here use the un-smoothed data as provided. While the period 397-234ybp show a -3.17°C variation at Vostock, the GISP2 data over the same period shows a maximum variation of just -0.15°C. If we take just these two temperature records as a very crude global average, we get a variation of -1.66°C. Add in further variations from elsewhere in the globe (which even if of the same sign we would expect to be yet smaller) and the Vostock data becomes less prominent still. Simply, the Vostock variations are not at all a good representation of global average temperature variations over the time periods you are examining.

       And to repeat this exercise for the biggest GISP2 variation, the +3.7°C variation over the 393 year period 8210-7817ypb. This appears strongly on the graph @507 as a +2.5°C variation. Over this full period 8210-7817ybp period the Vostock temperature ends at a similar temperature to the period start. Thus the two records average out as a +1.35°C variation and again would be diluted further when more temperature records are included. There is a complication with this data as the 8210-7817ybp period does include a 2.9°C Vostock deviation during part of the the 393 year period. When Vostock & GISP2 are average out, that deviation reduces to +2.2°C variation over a 91 year period. This is by far the most dramatic variation for an average of Vostock & GISP2 over the 10,000 years. Add in more data to get a better global average and it will certainly flatten out but probably still be visible. In the graph @207, this period shows a +0.4°C variation despite the smoothing, but in this 8-series global average the polar regions are grossly over-represented. (If Vostock & GISP2 were taken as representing respectively the whole antarctic & arctic, that would be only 7.5% of the globe.)

       Thus we can conclude that over the last 10,000 years when CO2 has been comparatively unchanging, there have been only small wobbles in global average temperature, as the graph @507 crudely demonstrates. Yet, as "GHG theory" predicts, now that CO2 is increasing there will be (and indeed is) a much larger increase in that global average temperature.

26688. michael sweet at 21:55 PM on 14 November 2015
       Video: Drought, Climate, Security, and Syria
       

       I like the analogy of AGW as being like a baseball player on steroids.  Say a pllayer hits 20 home runs in a season.  After steroids he hits 40 home runs.  How many should be attributed to the steroids?  All the sports fans I know say all the tainted home runs should be disqualified. For AGW that would mean that the entire Syrian war was due to AGW.  

       It is interesting to me that for AGW the standard is set so high for the question "did AGW cause this affect".  Hansen has show that 99% of all hot summers are caused by AGW  Scientists still say we do not have enough data to attribute the Syrian drought to AGW.  If it were sport we would dismiss all other contributions to the war and just say it was drought from AGW.

       What fraction of the cause needs to be AGW for AGW to be assessed as the main cause?  Since everything has multiple causes, it seems to me that AGW will never take the blame since there are always other contributors.  The Syrian war would not have occured without the record droght that preceeded it.  The drought was a record because of AGW.

26689. 0^0 at 20:24 PM on 14 November 2015
       The Skeptical Science temperature trend calculator
       

       Okay - I guess that was a bit trivial question.. In the output

            ar1         ma1      intercept   time(ds_hadcrut4_global_yr_subset$value)
            -0.5092 0.7643 -0.2845    0.0168
       s.e. 0.2951  0.2214  0.0351    0.0018

       I get 0.0168 ==> 0.168 C/decade and s.e. 0.0018 ==> +- 1.96*0.0018 = 0.035 C/ decade which is close to what I get now from calculator here for the 1980-2013 period (using the same for autocorrelation period)

       Trend: 0.164 ±0.044 °C/decade (2σ)
       β=0.016402 σw=0.00067164 ν=10.771 σc=σw√ν=0.0022043

       Using sarima(ds_hadcrut4_global_yr_subset$value,1,1,1) based on some ideas in a tutorial I get even more close to that

              ar1        ma1          constant
              0.2161  -1.0000    0.0165
       s.e. 0.1753    0.0999    0.0020

       Need to recheck my input data to find in which detail of my excercise the devil is.. 

26690. NN1953VAN-CA at 18:16 PM on 14 November 2015
       Climate's changed before
       

       Response to moderator
       Reference are Ice core tables:
       Vostok
       Greenland
       Historical Isotopic Temperature Record from the Vostok Ice Core
       Deuterium
       Age of content Temperature
       Depth the ice of the ice Variation
       (m) (yr BP) (delta D) (deg C)
       0        0      -438.0   0.00
       1       17     -438.0   0.00
       2       35     -438.0   0.00
       3       53     -438.0   0.00
       4       72     -438.0   0.00
       5       91     -438.0   0.00
       6     110     -438.0   0.00
       7     129     -438.0   0.00
       8     149     -442.9  -0.81
       9     170     -437.9    0.02
       10   190     -435.8    0.36
       11   211     -443.7  -0.95
       12   234     -449.1  -1.84
       13   258     -444.6  -1.09
       14   281     -442.5  -0.75
       15   304     -439.3  -0.22
       16   327     -440.9  -0.48
       17   351     -442.5  -0.75
       18   375     -436.6    0.23
       19   397     -430.0    1.33
       temperature variation from -1.84 at year 234 BP
       to                                         1.33 at year 397 BP
       temperature variation           3.17   time  163 years
       for Grenland ice core measurements temperature/ time variation takes longer, it is some 2K years for 3 degrees in temperature difference.
       The only reason I reference those two is that there temperature difference is the smallest at those points. Global temperature was different but variation may have been close to those changes.
       Sorry if my sentence:
       'I do understand nature around me' sounded dismissive as to reply to your statement:
       'Just because you don’t understand something doesn’t mean that science doesn’t either.'
       your opinion on my understanding.
       I was not intended to be dismissive, just stating that I do look around and look for reasons beyond.
       Why I mentioned C02 content as stable, for long period of time is to question statements that with present C02 content, GT is expected to be higher, and it is not.
       There are other factors as Milankovitch’s cycles, dust in the atmosphere as of volcanic activity or due to meteor hitting the earth, proportion variation in sea/land as at ice age or warm periods. etc
       I was not dismissing all other factors which are affecting GT change. 

       Present C02 concentration in the atmosphere is not reflecting GHG theory and that is what I was trying to express. 

       Moderator Response:

       [PS] In the role of moderator, my intention is provide guidance on what is acceptable on this site in terms of comments policy, constructive argument, and also to point to appropriate source material that should be considered. Please respond to the points made by other commentators that have addressed your argument directly. You would make discussion of your case against 'GHG theory' better if you did the following:

       1/ Outline your understanding of what science predicts. References to at least the IPCC if not primary literature preferred for this prediction.

       2/ Present the observations that you think contradict that prediction.

       As it stands at the moment, we believe you are mistaken about what GHG predicts and mistaken in your interpretation of ice-core observations. A clearer statement would both will help clear confusion.

26691. Digby Scorgie at 12:06 PM on 14 November 2015
       Video: Drought, Climate, Security, and Syria
       

       The video was interesting but did they have to use the horrible head-thumping background music?

       Is it because people today need this awful music to focus scarce mental resources on the task of understanding verbal messages?

26692. Riduna at 11:12 AM on 14 November 2015
       G R A P H E N E
       

       MA Rodger @ 18. … Graphene is a technology that is still in the laboratory

       Difficult to say because for commercial reasons, its users tend not to announce their activities. Market demand for significantly improved energy storage and the huge profits to be made from its provision, makes it likely that commercial use of graphene technology will occur sooner than later. A 15 year time span for its wide commercialization is an informed guess. It may be wrong.

       That Tesla batteries will use graphene technology is speculative – we don’t know. That Porsche will use graphene in batteries for its ‘Mission E’ (2018) sportscar is more likely given its claim of a 15 minute recharge time (1). The explicit statement of Sunvault-Edison that it will use graphene technology to power its Electron-1 car, (2016) if true, may indicate early commercialization (2).

       (1) http://www.drive.com.au/it-pro/porsche-unveils-allelectric-mission-e-sports-car-20150916-gjog22.

       (2) http://www.teslamotorsclub.com/showthread.php/52844-Edison-Electron-One

26693. Tom Dayton at 10:42 AM on 14 November 2015
       Models are unreliable
       

       Hawkins and Sutton are about to publish a peer-reviewed article explaining why and how choice of reference period is important when comparing model projections to observations. A pre-publication version is available now.

26694. sifeher at 03:43 AM on 14 November 2015
       Video: Drought, Climate, Security, and Syria
       

       Thank you for citing this interesting and timely article. The Middle East wars may not have been caused directly by global warming, but it is certainly contributing to the migration of millions from that region and also from Africa. It would be good to call this to the attantion of the G20 meeting in Istambul next weekend and before the Paris climate summit.

26695. Lloyd Flack at 20:10 PM on 13 November 2015
       G R A P H E N E
       

       I'm worried by the possibilty that cells could be damaged by the phsical presence of sharp particles in similar ways to asbestos. For now I think it wight be a good idea to use similar precautions to those used in dealing with asbestos. There is the potential for cancers which take a long time to develop,

26696. Trevor_S at 18:24 PM on 13 November 2015
       Lamar Smith, climate scientist witch hunter
       

       The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that 'my ignorance is just as good as your knowledge.” ― Isaac Asimov

26697. 0^0 at 17:21 PM on 13 November 2015
       The Skeptical Science temperature trend calculator
       

       I'm still a bit new to R and ARIMA - and I have quite some difficulty in locating where in arima output you actually get those values "1.52+-0.404"

       "Nick Stokes at 09:13 AM on 29 August, 2013

       KR,

       Thanks, I should have looked more carefully at the discussion above. I did run the same case using ARMA(1,1)

       arima(H,c(1,0,1),xreg=time(H))

       and got 1.52+-0.404, which is closer to the SkS value, although still with somewhat narrower CIs."

       I may have problems in getting my input data right - or processing / reading it.. Or both.. :(..

       Should those numbers be available from someplace here in this output? 

       Call:
       arima(x = ds_hadcrut4_global_yr_subset$value, order = c(1, 0, 1), xreg = time(ds_hadcrut4_global_yr_subset$value))

       Coefficients:
       ar1 ma1 intercept time(ds_hadcrut4_global_yr_subset$value)
       -0.5092 0.7643 -0.2845 0.0168
       s.e. 0.2951 0.2214 0.0351 0.0018

       sigma^2 estimated as 0.00739: log likelihood = 35.09, aic = -60.18

       ds_hadcrut4_global_yr_subset$value contains - or at least should- yearly averages from monthy anomalies 1980 - 2013..

       Thanks!

26698. uncletimrob at 17:07 PM on 13 November 2015
       Why were the ancient oceans favorable to marine life when atmospheric carbon dioxide was higher than today?
       

       Sorry, but your question asks the impossible because 300 million years is so big compared to anything we as humans have experienced. 

       Its the same scale as saying something happend 1 year ago, and then asking about a year and 1/10th of a second ago.  

       Geologic time scales are hard to comprehend and  of course can only be very general and never down to the nearest year. I'd suggest that the "error" is a few tens of millions of years, but will be happy to be corrected by somenone with more expertise than me.

26699. Tom Curtis at 16:26 PM on 13 November 2015
       G R A P H E N E
       

       Some graphene related MSDS:

       Graphene

       "Potential Acute Health Effects: Slightly hazardous in case of skin contact (irritant), of eye contact (irritant), of ingestion, of inhalation. 

       Potential Chronic Health Effects:
       CARCINOGENIC EFFECTS: Not available.

       MUTAGENIC EFFECTS: Not available.

       TERATOGENIC EFFECTS: Not available.
       DEVELOPMENTAL TOXICITY: Not available.

       The substance is toxic to upper respiratory tract. The substance may be toxic to cardiovascular system. Repeated or prolonged exposure to the substance can
       produce target organs damage."

        

       Graphene films on SiO2/Si substrate:

       "Potential Health Effects: Generally not hazardous in normal handling, however good laboratory practices should always be used."

       Graphene oxide:

       "EMERGENCY OVERVIEW: THIS MATERIAL MAY BE AN IRRITANT TO EYES, SKIN OR RESPIRATORY TRACT.
       Potential Health Effects: Eyes – may cause eye irritation. Skin – may cause skin irritation.  Respiratory tract/inhalation – may cause irritation.Ingestion – not hazardous in normal industrial use circumstances.  Cancer – natural graphite may contain small amounts of impurities of 0% - 1% crystalline silica, which is listed as a Group 1 carcinogen by IARC and as a suspected human carcinogen by ACGIH. Inhalation of high concentrations of crystalline silica over prolonged periods of time has been linked to an increase in lung cancer. Inhalation of high concentrations of crystalline silica over prolonged periods of time may also cause silicosis.  Inhalation of high concentrations of graphite dust over prolonged periods of time may cause pneumoconiosis."

       Reduced Graphene Oxide:

       "EMERGENCY OVERVIEW: THIS MATERIAL MAY BE AN IRRITANT TO EYES, SKIN OR RESPIRATORY TRACT.
       Potential Health Effects: Eyes – may cause eye irritation. Skin – may cause skin irritation.  Respiratory tract/inhalation – at high concentrations may cause irritation. Ingestion – not
       hazardous in normal industrial use circumstances.  Cancer – natural graphite may contain small amounts of impurities of 0% - 1% crystalline silica, which is listed as a Group 1 carcinogen by IARC and as a suspected human carcinogen by ACGIH. Inhalation of high concentrations of crystalline silica over prolonged periods of time has been linked to an increase in lung cancer. Inhalation of high concentrations of crystalline silica over prolonged periods of time may also cause silicosis.
       Inhalation of high concentrations of graphite dust over prolonged periods of time may cause pneumoconiosis.
       Physical Hazards: Graphite is electrically conductive. Care should be taken, therefore, to avoid accumulations of graphite dusts or powders in places where these accumulations could cause shorting of electrical switches, circuits or components."

       Graphene Films, TEM grid:

       "Potential Health Effects: Generally not hazardous in normal handling, however good laboratory practices should always be used."

       The upshot appears to be that there is no evidence of significant toxicity from graphene itself, although doping agents can make it toxic.  It does act as an irritant (as does any fine dust), but that is not a major problem.

26700. Riduna at 12:55 PM on 13 November 2015
       G R A P H E N E
       

       Katesisco  @ 9– The US Materials Safety Data Sheet warns against inhalation of pure graphine particulates (dust) which causes cellular damage in the lungs resulting in emphysema. It describes skin and eye contact with dust as a mild irritant and gives no information on carcinogenic effects, if any. More work on its industrial use is needed since it does not address graphene compounds.

       Moderator Response:

       [PS] A reference would help please.

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