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Comments 26801 to 26850:

  1. So what's really happening in Antarctica?

    Morgan01944 @5, the full context of your final quote reads:

    "One other thing is certain: West Antarctica has been losing mass at an increasing rate since the 1990s and, irrespective of what is happening further East, that trend looks set to continue. Going to the other end of the Earth, the Greenland ice sheet has also been losing mass at an accelerating rate since around 1995. Greenland is now the single biggest source of mass to the oceans. These trends at both poles are huge signals that are unequivocal and uncontested."

    West Antarctica is indeed at one pole, as Greenland is at another.  Further, their trends in ice loss are indeed both huge and uncontested (including by Zwally et al).  That it is not clear as to the trend in the East Antarctic Ice Sheet has no bearing on that claim.  Ergo, your juxtaposing this quote with the two others, which discuss the reasons for lack of clarity in Eat Antarctica, shows at best careless reading - not a problem with the OP.

  2. So what's really happening in Antarctica?

    Not one of your more convincing posts:

    "If we knew the snowfall history perfectly then there wouldn’t be any controversy!"

    "So what is really happening? One thing that Zwally’s study does highlight is how difficult it is to nail what is happening in East Antarctica because the signal is small and contaminated by unwanted effects that are as large or even large"

    " trends at both poles are huge signals that are unequivocal and uncontested."

    Moderator Response:

    [DB] Note that this article is a repost.  Please refrain from arguments from your personal incredulity, like you have done here. 

    If you have substantive issues with the content of the article, please cite those specific issues along with a link to a published analysis or examples from the primary literature that support your contentions.

  3. So what's really happening in Antarctica?
    Looks like realclimate DNS is down/subverted, i have informed Prof. Schmidt. The majority of nameservers that i checked claims no authoritative nameserver exists, a minority redirect to IP 208.91.197.217, which is also returned by directly querying the listed authoritative nameservers. whereat resides a spoof site claiming the domain has expired, and inviting one to buy it. A whois check is more illuminating, i have sent the results on to Prof. Schmidt also.
  4. So what's really happening in Antarctica?

    The "issue" with RC manifests itself primarily on weekends, as also appears to be the case here.

    So it's simply a regular server mainteance or they don't run a server on weekends. No surprise, climate scientists usually don't have too much volunteer money to spare to maintain their ageing server. RC has been running for over 10y with the same graphical appearance which is quite impressive in those days of constant (and not necessarily useful) technology changes.

  5. G R A P H E N E

    Ed Wiebe @ 3 icorrectly points out that Superconductivity of Graphene coated with Lithium is achieved at K5.9, not room temperature.

    The sentence: ‘When coated with Lithium it becomes a superconductor, having no resistance to an electric current at room temperature’ is wrong and the text has been modified to show deletion of the sentence.

  6. The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy

    Here's a scenario by WWW and Ecofys that does the job of getting rid of fossil fuels by 2050. You should note that the total energy consumed in 2050 is about one-third of the amount in the RCP2.6 scenario I referred to in my post. Also, the amount of renewables and non-BECCS bioenergy looks (eyeball) similar between the van Vuuren and WWF cases, somewhere around 200-250 EJ/year.

    This would be a huge challenge over 35 years and relies very heavily on energy efficiencies as well as aid to developing countries to allow them to grow their economies without increasing emissions. Much of the capital stock we have like power stations would have to be scrapped before its economic lifetime was up.

    To me, this scenario looks even less feasible than the one that relies on CCS and BECCS.

  7. So what's really happening in Antarctica?

    bwilson4web - I've noticed RealClimate has hosting issues from time to time for several years. I suspect this is just another hosting farble, and will be resolved in due course. 

  8. So what's really happening in Antarctica?

    Hi,

    I'm having difficulty reaching the "RealClimate" web site with symptoms suggesting the domain name may have been redirected to someplace else. Is there another source and/or an IP address of the server?

    Thanks, Bob Wilson, Huntsville AL

  9. 2015 shatters the temperature record as global warming speeds back up

    I think Cooper13 has a good point. Next year, 2016, will be the appropriate year to add to the chart under the category of El Nino years. It should be empahasized that 2015 will be a record, even before the large influence of the strong El Nino is felt. 

  10. 2015 shatters the temperature record as global warming speeds back up

    I predict we'll have 20 years of people claiming "global warming stopped in 2015 - now it's for real!"

  11. The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy

    Andy: I was using my mark-one eyeball to estimate the changes in gas and oil use from the thicknesses of the blue and orange bands.  Gas use seems hardly to change at all up to 2030 or so.  Oil use does decline somewhat.  But even with the large decline in coal use, the overall rate of decline in fossil-fuel use for the next two decades still does not seem drastic enough to me.  It would help to see some numbers!

    It's a bit of a worry when you say the scenario "still overshoots the carbon budget".  Also, talk of "negative emissions" raises my eyebrows — I'll believe it when I see it!

    What I'd really like to see is a graph showing the way fossil-fuel use has to decline in order to satisfy the 600 Gt budget — without any CCS.  I would love to see such a graph compared with RCP 2.6.  Any chance of that?

  12. The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy

    Digby: In the second and third graphs, I think it's clear that fossil fuel use without CCS peaks in 2020, followed by a decline, with, for example, no coal without CCS after 2060. Although that's a very ambitious mitigation scenario, it still overshoots the carbon budget, requiring net negative emissions after 2060, as shown in the first figure in my original post. That's where the BECCS is needed.

    The 600Gt CO2 budget number that Flannery mentions is a lot lower than the figure of 1000Gt that you would find in the IPCC AR5 reports for a 66% chance of staying below 2 degrees. However, the lower number is more appropriate as a go-forward budget for fossil fuel use from now, because you have to subtract the three years or so of emissions since AR5, as well as make allowance for cement and land-use emissions over the rest of the century. 

  13. The Road to Two Degrees, Part One: Feasible Emissions Pathways, Burying our Carbon, and Bioenergy

    Andy Skuse: That sums it up well: to "rely on sequestration as the main response to the climate crisis" would be to face "a gigantic problem".  Some sequestration would help but it cannot be used as an excuse not to cut the burning of fossil fuel.

    With regard to the latter, I'm busy reading Tim Flannery's "Atmosphere of hope" and find it difficult to reconcile his comments on our "carbon budget" with the graph showing RCP 2.6 fossil-fuel use.  He states that we have a budget of 600 Gt of carbon dioxide remaining and are currently emitting just over 30 Gt annually from burning fossil fuel.  At current rates we'll use up the budget by 2028.  Even if the rate is capped at 30 Gt, that still extends the deadline to 2035 only.

    I've seen similar figures elsewhere but I've also seen comments disparaging the whole idea of trying to quantify a carbon budget — the uncertainties are large.  If we accept the budget of 600 Gt, then we can carry on as usual for about two decades and then we have to stop burning fossil fuel completely.  If the rate of fossil-fuel use declines considerably, then we can continue for longer.

    Now, if I look at the above graph, I see the use of oil and gas declining only slightly over the next two or three decades.  Coal use declines a lot and is compensated for by the use of gas plus CCS.  However, the overall reduction in fossil-fuel use does not seem in any way sufficient to meet Flannery's requirement.  Have I misinterpreted things?  Has Flannery erred?  Is the RCP 2.6 graph only part of the picture?

  14. SBC Energy Institute Climate Factbook

    enSKog @1, the claim on page 8 is not so much wrong as oversimplified.  As shown in this image from Wild et al (2012), the net effect of reradiation is that there is a 342 W/m^2 back radiation, so that back radiation is 86% of upward IR radiation at the surface:

     

    More importantly, IMO, only 239 W/m^2 escapes to space, so that the Outgoing Longwave Radiation is only 60% of the upward IR radiation at the surface.  The difference between the two (158 W/m^2) is the "Total Greenhouse Effect".  The difference between the upward IR radiation at the surface and the total IR radiation from the atmosphere (ie, 239+342-397 = 184 W/m^2) is made up for by other energy inputs into the atmosphere, specifically 79 W/m^2 of absorbed solar radiation, 85 W/m^2 from evaporation (including the release of H2O associated with photosynthesis, ie, transpiration), and 20 W/m^2 associated with convection (sensible heat).  

    As a side note, the same diagram is uses by the IPCC AR5 as Fig 2-8 except that upward IR radiation is given as 398 W/m^2 and evapo/transporation is given as 84 W/m^2 with no other changes, except related changes to bracketed figures, ie, the uncertainty ranges.

    If we take a more detailed look, we note that energy absorbed by a single molecule (from any source) and then emitted as radiation has an equal chance of being emitted in any direction.  This is sometimes glossed as "LWR is absorbed but then radiated in ALL directions", but of course individual molecules emit single photons on reradiation, each of which must have a specific direction.

    It might be supposed that this must result in a collection of molecules radiating equally in all directions, but again this is not true.  If we consider a parcel of air defined by vertical planes perpendicular to the surface with top and bottom boundaries defined by concentric shells around the Earth's center, then the air in the top of the parcel will be thinner and (in the troposphere) cooler than that in the bottom of the parcel of air.  As the parcel of air has measurable thickness, some of the IR radiation from the air at the bottom of the parcel going upward will be reabsorbed by air in the parcel above it, and vice versa.  Because of the difference in temperature, the air in the upper portion of the parcel will reradiate at a slower rate than that in the lower portion, with the net effect that the upward radiation from the parcel will be less than the downward radiation from the parcel.  This difference is the core reason why the greenhouse effect exists.

    The point is that the booklet's claim and your gloss both represent simplifications of a more complex process.  Both can be made true by appropriate qualification and or change in wording, but only by adding significant complexity.  The same is also true to a lesser extent of my explanation above.  In any teaching situation, you have to make these tradoffs between absolute accuracy and keeping things simple enough for people new to the subject to understand the concepts.  Unfortunately, those same tradeoffs result in potential misunderstandings, which are often exploited by deniers to spread confusion and doubt.  (For your gloss, the confusion is that outgoing LWR must equal the downard IR radiation at the surface - something I have seen argued by deniers.)  So, while I would have preferred to see an explanation of the importance of the temperature gradient in the atmosphere to the greenhouse effect, and the use of the word "net" on the page you discuss, overall the booklet is very good and the "errors" are only those of approximation needed to keep things simple in a teaching context.

  15. SBC Energy Institute Climate Factbook

    Looks pretty good but on page 8 they say

    "90% of the upwardly directed LWR is
    absorbed by GHGs and radiated back
    downwards, ...."

    90% of up LWR is absorbed but then radiated in ALL directions!

    Is it too late to get this corrected? Don't want to give the denialists anything to pick at.

  16. Climate's changed before

    It might help to quote some reliable sources from an earlier period before climate change became a political issue. For example: was rapid temperature change thought to be a or the cause of mass extinctions in the 80's or 90's? 

  17. 2015 shatters the temperature record as global warming speeds back up

    If 2015's high average temperature is in part influenced by a strong El Nino, then it is likely that several of the succeeding years will be cooler (even as the underlying trend remains unequivocally upward). This will surely lead to new claims that global warming has stalled, a cooling trend is upon us, there is no link between warming and CO2 concentrations etc etc  And yes, these claims will be repeated in major newspapers, albeit mainly in the 'comment' sections, where scientifically illiterate 'skeptics' are given free rein to spout whatever nonsense they like without any need to reference the facts.

  18. 2015 shatters the temperature record as global warming speeds back up

    With all these precise temperature measurements of known El Niño, La Niña events, plus volcanic influences, how far are we away from determining the climate sensitivity for a doubling of CO2?

    Moderator Response:

    [AS] Spelling of La Niña corrected

  19. 2015 shatters the temperature record as global warming speeds back up

    Foster Brown - I think that depends on what you mean by "deep". The Peruvian cold upwelling should be say "very deep". I think the article would be more correct if it said "deeper" (<500m) rather than deep.

  20. 2015 shatters the temperature record as global warming speeds back up

    Please correct me if I am wrong,  but  the phrase "During El Niño events, hot water is transported from the deep ocean layers to the surface" doesn´t seem accurate.   The typical situation in the Pacific Ocean off the Peruvian coast is upwelling of cold, nutrient-rich water that maintains a highly productive ecosystem.   El Niño tends to reduce this upwelling and its corresponding cold subsurface water.  

    Moderator Response:

    [Rob P] The post by Dana Nuccitelli is correct although, as Phil Scadden points out, "deeper ocean layers" would be a better description. The thermocline (the depth where there is a sharp contrast between the warmer well-mixed surface layers and the cooler layers beneath) across the tropical Pacific is 'tilted'; shallower in the eastern Pacific where a lot of upwelling occurs, and deeper in the western tropical Pacific.

    The westward tropical trade winds pile up warm water in the west - which is why sea level is higher in the west than in the east. This also drives an accumulation of warm water which extends well below the surface and thus displaces the thermocline to greater depth. This is known as the western Pacific warm pool.

    When the trade winds relax, buoyancy and the pressure gradient force (a response to gravity) take over and the warm water travels not only eastward (in pulses known as Kelvin waves), but also surfaces. This greater-than-normal exchange of ocean heat with the overlying atmosphere is why the global surface temperature spikes with El Nino. The other part of the equation, as you point out, is a shutdown of the cold water upwelling as the subtropical gyres spin down temporarily.         

  21. Satellites show no warming in the troposphere

    Something I'm having trouble reconciling is the comparison of UAH and RSS datasets. The article states, "Throughout the history of Tropospheric temperature measurement, the UAH analysis has always been lower than RSS for all temperature products." However, as Knaugle pointed at #51, it's RSS that's been the outlier, or at least it was until UAH 6.0 brought UAH into line with it. Spencer (of UAH) talks about the discrepancy in a blog post from a few years back, promising he's not been "bought off by Greenpeace", and even going so far as to say that in his boss's (John Christy) opinion, "RSS data is undergoing spurious cooling."

  22. 2015 shatters the temperature record as global warming speeds back up

    I think it is well worth pointing out that the 'spike' in global temperatures for 1998  and that El Nino event occurred AFTER the El Nino (which started in the winter of 1997).

     

    The current 2015 El Nino is at the same stage the '97-98 event was in 1997,  NOT 1998 (where we see the huge temperature spike in the annual temperature record); that anomalous spike is consistently misused to claim 'no warming in the past 15+ years. Thus, comparing temperatures for the global/annual record for 2015 vs 1998 is not apples-to-apples.

    As I understand it, El Nino typically has a 3-6 month delayed impact on global temperatures. 2015 can be directly compared to 1997, and once the El Nino effect fully manifests itself, we can then evaluate 2016 to 1998 as a true apples-to-apples comparison.

  23. Book review: Climate Change, What Everyone Needs to Know

    The link to "Click here to read the rest" isn't working. Here's the correct URL: http://www.theguardian.com/environment/climate-consensus-97-per-cent/2015/nov/17/book-review-climate-change-what-everyone-needs-to-know

  24. Exxon climate revelations are just part of a long history of science misinformation

    I found a line in Ryland's article at 9 interesting:

    "Many owners found that under this policy, their properties became almost unsaleable"

    If acknowledging projected sea level rise makes properties unsalable, how long will it be before most sea front land becomes worthless?  After Katrina many inland states complained about insuring the coastline property damage  After Sandy they raised insurancce rates so that in my area (Florida) some houses had larger insurance payments than mortgage payments.  Those increases were withdrawn.  After the next hurricane will the properties become insurable?  

    Investors will notice when properties start to fall in value due to sea level rise.  It might be sooner rather than later if acknowledging sea level rise caused properties in Australia to become unsalable.  Perhaps then the conservatives will want to take action.

  25. Exxon climate revelations are just part of a long history of science misinformation

    Ryland, permit me to take you to task on your comment: "Perception is reality", in Ryland @ 9 [or thereabouts ~ as the commentary enumeration has been re-jigged a little bit, in this thread].

    Perception is certainly not identical to reality . . . but, where sanity prevails, perception closely approximates reality.

    Fantasy (as exhibited by frequent propaganda pieces in The Australian) is where the perception [ of Global Warming / Climate Change ] has little overlap with reality.

    "Fantasy" [ no double entendre intended :-)  ] there includes the determined effort to deny reality . . . and is clearly a way of thinking divorced from sanity.

    I would like to be able to say candidly that it is "un-Australian" to be fantastically divorced from reality . . . but if I were to do so, then my perception would indeed be faulty. Still, we can hope ~ that in 10 years or so, The Australian will eventually embrace scientific reality in place of the [current] fantasy. Then, it will be worth subscribing to that paper.

  26. Exxon climate revelations are just part of a long history of science misinformation

    ryland originally (now inline @1):

    "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"

    ryland @9

    "As for your other comment, yes I'm sure there are those that consider the belief in man made climate change is akin to a religion and also there are those who believe there is a conspiracy. Remember perception is reality so those that have these perceptions may well also consider the prophecies of doom regularly emanating from the IPCC, climate scientists and politicians to be misinformation campaigns. Personally, I don't subscribe to those perceptions but accept that others do."

    ryland @9 is a bit of an evasion, in that my other comment was not that he also shared those views, but that he considered them rational.  However, supose he intends it as an adequete response to my claim, ie, that he acknowledges the existence of those views without considering them rational.  In that case it completely destroys the logic of his point in his initial post.  I acknowledge the existence of people who think the Earth is flat, or that the Sun orbits the Earth.  I wouldn't dream of bringing them up as a relevant issue in a discussion such as in the OP in that their views are clearly irrational.  So what if people can only irrationally (or being deluded by others due to limited sources of information) claim the IPCC or other climate scientists indulge in "public misinformation campaigns".  That has zero bearing on the fact that documentary evidence proves that Exxon was advised by their own scientists that global warming was real, and that they then funded organizations claiming the opposite.  Indeed, the mere falseness of "those perceptions" mean that the documented behaviour by Exxon does not have equivalents from the climate science side of the debate.

    So, granted that those deluded about climate can also make a "tu quoque" which is not only a fallacy of reason, but grounded on false premises as well.  So what!

  27. Exxon climate revelations are just part of a long history of science misinformation

    ryland @9, I did read the piece in The Australian.  I have previously noted that The Australian's coverage of climate science bears more resemblance to propoganda than to reportage (See here and here).  The article to which you linked is a case in point.  The passages you so heavilly bold consist almost entirely of editorial content by The Australian.  The only direct quote of Bob Stokes, to the effect that the prior policy "...sterilised land from development because it was a very cautious approach" says nothing about whether or not projections of rising sea levels will be used in the new standards.  Your bolding of it, therefore, amounts to a rhetorical bluff.  The quote does not support your opinion, and the opinions of The Australian's journalist as to the reasons for and effect of the policy do not constitute reporting on the policy, but editorializing on it.

    Better is the reporting by the Sydney Morning Herald (linked above, but which you ignored) where we learn that:

    ""Changes to climate are likely to intensify our existing hazards," Mr Stokes told Fairfax Media, adding that while many of the problem areas are known, other new ones may emerge."

    Note the difference between The Australian's heavily editorialized reporting and the direct quote and attribution from the SMH.  However, 'climate change' is used as a weasel word by some deniers, so I looked further, including to the report by the Chief Scientist under the L/NP coallition which resoundingly endorses use of IPCC projections of sea level - giving a clear indication of the position of the government.  You ignored that as well.  No doubt you will also ignore the NSW governments page on the impacts of sea level rise, which so resoundingly rejects the IPCC position that it states it as the likely impact, and links to the relevant IPCC chapter. 

    Finally, I watched Bob Stokes talk introducing NARClim (the NSW government funded regional climate modelling project to aid future development decision making), in which he briefly mentions the reforms on coastal planing, saying (at 15:17):

    "Finally I just wanted to refer to coastal reforms.  Obviously one of the key impacts in relation to climate security is the impacts of rising sea levels and greater storm activity on coastline.  That's something we are dealing with through coastal reforms - effectively working with local councils to find out what the impacts are embayment by embayment of rises in sea level, and how that needs to be factored into decisions about development."

    Of course, all that must be irrelevant.  After all you have The Australian's editorializing masquerading as reporting so can turn a blind eye to everything else, including the actual opinions of the minister involved.

  28. Exxon climate revelations are just part of a long history of science misinformation

    I think you probably didn't see the piece from the Australian that stated

     

    "The initiatives mark the second phase of the Coalition government’s demolition of the previous Labor government’s policy, which among other things directed local councils on the coast to enforce the climate change and sea level rise predictions of the UN Intergovernmental Panel on Climate Change.

    Under that regime, councils in some cases included sea-level rise warnings on the planning certificates of some seaside properties based not on what was happening on the beaches concerned — including one that is acquiring sand naturally and pushing back the sea — but on IPCC predictions.

    Many owners found that under this policy, their properties became almost unsaleable.

    “It sterilised land from development because it was a very cautious approach,” Mr Stokes said.

    The new strategy will employ scientists and engineers to look at what is happening in each of 47 coastal sediment compartments, and make that information available to councils through a new NSW coastal council.

    I think that, especially the last paragraph, makes it fairly plain the NSW government is changing the policy and will not be basing decisions on IPCC predictions but on empirical assessment of the local beaches. 

    As for your other comment, yes I'm sure there are those that consider the belief in man made climate change is akin to a religion and also there are those who believe there is a conspiracy.  Remember perception is reality so those that have these perceptions may well also consider the prophecies of doom regularly emanating from the IPCC, climate scientists and politicians to be misinformation campaigns.  Personally, I don't subscribe to those perceptions but accept that others do. 

    Moderator Response:

    [JH] For future reference, please specifiy who you are responding to. Thank you.

  29. 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!!!

  30. 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.

  31. 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. 

  32. 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. 

  33. 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.

  34. 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?   

  35. 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?

  36. 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.

  37. 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.

  38. 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.

  39. 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.

  40. 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.

  41. 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.

  42. 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?

  43. 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.

  44. 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 temptemperature graph

    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:

    temp.graphs

     


    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 studiesproxy locations

    temperature

    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.

  45. 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.

  46. 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.

  47. 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

  48. 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.

  49. 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.

  50. 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.

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