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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 28251 to 28300:

  1. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Andy Skuce, there will certainly be a limit to intermittent power penetration without storage and/or long distance transmission... but there is no reason that the remainder has to be made up by fossil fuels. There are many countries with large hydro power resources which could be linked to neighboring countries with wind/solar power to provide stable electricity at lower prices. We can see this currently with Denmarks >40% wind power working symbiotically with hydro power in Norway and Sweden. The same could be done with nuclear, but only France really has high enough nuclear penetration to make it feasible (that is, trading their stable baseload for lower cost wind/solar from neighbors).

    Thus, it seems plausible to me that most of Europe, and many other places around the world, could completely decarbonize without needing electrical storage... and again, all indications are that the current free-fall in battery storage costs will continue and make large scale grid storage economically feasible soon. Ergo, lots of reason to think that we could see rapid decarbonization, driven purely by economics, in the coming decades.

  2. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    I largely agree with Joris that opposition to nuclear power on the grounds of safety is unfortunate and that nuclear fear has been exaggerated. Nevertheless, nuclear fear is a global reality and not one that will go away very easily, certainly not by mocking people who are scared of anything radioactive nor, sadly, by lecturing them on the facts of death counts at Chernobyl, Three Mile Island or Fukushima.

    My guess is that many, maybe most, people now have a natural disgust reaction when it comes to nuclear power and that no amount of argument will persuade them otherwise. It's a bit like Americans with their gun culture or my aversion to eating dog. You could tell me how tasty and nutritious dog meat is and that it can be provided without cruelty, but I'm not going to listen to a word you say.

    Public rejection of nuclear power is a sad reality and unless the nuclear industry and its friends can find a better way of changing people's minds, it is not going to become a major player in the future. Nuclear proponents are often proud of their hard-headed approach to facts, but they seem to be in denial of the reality that greatly increasing nuclear power in almost any country is going to run into determined public resistance that won't be overcome for a generation or more.

    Some of the most strident anti-nuclear sentiment I have encountered is in France, which benefits from cheap(ish), carbon-free electricity, produced for decades without a major accident. In the same country, an estimated 40,000 die every year from diesel pollution. 

  3. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    While it is true that countries like Denmark sometimes get >100% of their energy from intermittent renewables, they can only do this because they are part of a larger grid that includes coal, gas, bioenergy, nuclear and hydroelectricity. If we are looking at the maximum feasible penetration of solar and wind, I am (mostly) persuaded by Jesse Jenkins' argument that within a grid, the maximum penetration of intermiitents is going to be about 40%. Of course, this would not apply if there were a cheap electricity storage technology.

    A place worth watching for renewables penetration is Hawaii. With abundant solar, wind and geothermal potential and with current diesel-powered electricity selling at 31cents per kwh (and a legislated mandate to go 100% renewable), this is a place to watch. Or, rather, places to watch since every island has its own grid.

  4. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    The discussions seems to be getting sidetracked, as happens often in other forums, into another tired, hackneyed discussion about nukes vs renewables.

    This paper is important enough, it seems to me, to discuss it's specific claims and take these side-debates elsewhere.

    Particularly, I would like to know how Andy Skuce's excellent article just posted on this site intersects with the above study. I assume that it would move the "Hard Deadline" date from 2018 to some even earlier date, but I'm not sure how much earlier. 2017? 2016? Now? Last year? Three decades ago??...

  5. Rob Honeycutt at 02:00 AM on 16 July 2015
    There is no consensus

    britty5096...  Are you looking at the correct tab? The advanced tab specifically states that it's a survey of research papers.

  6. Joris van Dorp at 01:30 AM on 16 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    CBD, the subsidies report I linked considers both "consumer support" subsidies and production support subsidies, which makes it a little complicated to understand exactly how much money goes to subsidise production, which is what should concern us if we want to evaluate the competitive performance of different energy technologies.

    For example, the report considers the fact that oil consumers in many oil exporting countries buy oil products at the domestic cost of production (as opposed to the international market price, which can be several times higher in many cases) as a 'consumption subsidy', and lumps this huge figure (about 400 billion/a) together with actual production subsidies, somewhat obscuring the effective production tax/subsidy situation. 

    Moreover, both these "consumption subsidies" and tax revenues are highest by far for oil products. This follows logically from the fact that oil products are heavily taxed in most OECD countries, while they are sold at the cost of production in most oil exporting countries. 

    Ignoring so-called 'consumption subsidies' for oil,  the 8 to 1 figure for the ratio between tax revenues and production subsidies (~800 billion to ~100) billion is in fact concluded by this report. The report does not show that coal or gas generally recieve more subsidies than they yield in tax revenues, contrary to your claim above. In fact, the report explicitly states that total coal production subsidies are only 3 billion, on page 5. I assume you are aware that this is virtually nothing when considering the massive amount of electricity provided by coal.

    Concerning your PPA figures for recent utility solar in the USA, I have also seen these figures. AFAIK, no details have been provided about the base investment cost. If the solar resource of these projects offers 1700 full load hours of insolation equivalent, if the PPA prices are constant prices, and if the discount factor is 8%, then a PPA price of 0.0553 $/kWh implies a total lifecyle cost of at most 1$/W in present value money, to break even over a 20 year PPA lifetime. This would be very cheap for utility solar. Certainly it is far cheaper than estimates for utility solar from recent literature. It would be good to know how such a low lifecycle cost was achieved.

    Of course, none of this is to say that solar is competitive with FF or nuclear. Even if the 0.0553 is in fact fully unsubsidised (which requires more detailed information on the project finances) then this price only matters during times when the sun is shining. Outside of those hours, the value of these solar plants is zero, since they are not dispatcheable. As such, they are only competitive with FF when the sun shines. That makes solar (or wind) power usefull only as a fuel saving technology for traditional fossil fuel power generation. The fuel cost of coal power is about 3 ct/kWh, so the PPA of solar would have to drop to below 3 ct/kWh to be a competitive fuel saving measure paired with a coal power plant.

  7. There is no consensus

    britty5096 - Keep in mind that "unpopular opinions" are absolutely not "null results", but rather the very points that will be noted, especially if they are supported by the evidence. 

    And the survey (not poll) of abstracts shows very very few items expressing the 'skeptical' "unpopular opinions", and almost none (personally, I can't think of any) that have held up to scrutiny against the evidence. 

  8. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Joris van Dorp - "...how solar or wind can ever be cheaper than nuclear on a cloudy, windless day?"

    Because in reality we aren't talking about single solar or wind stations, but rather networked systems extending over geographic areas. And as demonstrated by Archer et al 2007Supplying Baseload Power and Reducing Transmission Requirements by Interconnecting Wind Farms, connecting even as few as 20 wind stations in the US MidWest results in a dependable baseload capacity of 33% average power, as weather systems won't cover all of the locations at once. Adding solar to the mix would greatly increase the available percentage, as would extending the geographic region considered. 

    Overall the papers I've seen indicate that some overcapacity, rather than storage/buffering, is more economic in renewables with current technology. And for the small percent of the time that fossil backup is required, the carbon emissions for that backup amount to only a few percent of the emissions required without renewables. 

    At this point wind energy is one of the cheapest additions to energy portfolios, with utilities increasing their contract purchases accordingly. 

    Nuclear power is certainly an option, and IMO needs to be part of the energy mix - but it's rather expensive (for many reasons), requires very long lead/build times, and notably comes in quite large (as in not incremental) chunks, making it hard to plan for and finance. 

  9. There is no consensus

    Skeptical Science:

    Thank you for this.  I would also count myself among those who agree that climate change is impacted by human activities.  But can you please consider changing your summary of it to more accurately reflect what the study's abstract says?  Firstly, this is not a poll of scientists, but a poll of published scientific papers (so there is probably a lot of representation from a handful of prolific scientists).  Also, it says that "66.4% of abstracts expressed no position", and 97% of the abstracts that expressed a position endorsed AGW.  In total, only 33% of all abstracts (not scientists) explicitly endorsed AGW.  Furthermore, there is often a bias against null findings in any field, which encourages "exciting" results to be published while null findings (especially unpopular opinions) may be suppressed by peer reviewers, journal editors, or lack of funding.  So really, if you want to rephrase it, it should say "97% of published abstracts that stated a position on AGW agreed with it".

  10. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    JvD  It will be interesting to see if in the fullness of time, concerns on effects of wind turbines on the human brain are substantiated or not.  if they are substantiated and that may well not be the case, wind turbines may have to deal with concerns from the public just as the nuclear industry has had to do.  A piece in  The Australian states:

    "There has been a report from the National Metrology Institute of Germany that concludes exposure to infrasound below the range of hearing could stimul­ate parts of the brain that warn of danger. It finds that humans can hear sounds lower than had been assumed and the mechanisms of sound perception are much more complex than previously thought.

    The researchers do not claim the results are definitive regard­ing wind turbines and health impacts, and say more work is needed.

    But the research builds on recen­t work in Japan and Iran — and investigations by NASA dating back to the 1980s — that suggests the health science of wind energy is far from decided and would benefit from further inquiry"

  11. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    JvD @28:

    "the fact that fear of nuclear is universal does not follow from nuclear's performance in terms of safety and environmental effects. Coal based power has killed millions of people, and still kills more people every day, globally, than nuclear has killed in its entire existance."

    That establishes only that the risks of coal powered are under appreciated.  Not that the risks of nuclear have been overestimated.  Of course, it is very probably that those risks have been overestimated by a sizable number of people - but those people have had little influence on regulations.  It is therefore entirely uncertain that overdesign of safety features has needlessly increased the cost of nuclear power.  Given a priori assumptions about the efficiencies of government, it likely that it has been both overregulated in some aspects and under regulated in others (as chernobyl and fukushima demonstrate).

  12. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    JvD @23, I have no intrinsic objection to nuclear power.  Indeed, I am happy enough with it that I used to stor a sample of uranium ore in my bedroom as a teen, and still consider it short sighted and stupid that Australia persists in operating diesel/electric rather than nuclear submarines.  Having said that:

    1)  Nuclear power as the primary power supply can only be an intermediate term solution as, if it is considered a long term solution, economic growth will result in waste heat becoming as bad a global forcing as CO2 is currently (and a much worse regional forcing);

    2)  Given (1), to the extent that we can solve the need for carbon free energy using renewables, that is a step in the right direction;

    3)  There is no inprinciple reason why renewables cannot supply all our energy needs, even if populations grow to double their current levels, world economic growth continues unabated, and third world per capita GDP catches up with the future levels of western per capita GDP.  However, the use of nuclear power, particularly over the next 50 odd years may substantially reduce the cost of going to a carbon free economy;

    4)  I do not need to determine whether or not a nuclear/renewable mix or a pure renewable strategy will be most cost effective.  Rather, we need to ensure there is an appropriate price on carbon and let investors sort it out; but

    5)  For whatever reasons (rational or irrational), nuclear power is a hard sell in some societies.  At the same time for reasons entirely irrational, effective action on AGW is a hard sell in nearly all societies.  I do not think it is good policy to shackle the later to the former.  Doing so generates a substantial risk that we do not undertake effective action on climate change.  It may have the payoff of making available a cheaper mitigation strategy but only at the substantial risk of having no mitigation strategy.

    Points (4) and (5) are the key points IMO.  I have absolutely no problem with people inclined to do so promoting the use of nuclear power.  As a political policy, I would by likely to vote for it given reasonable confidence of certain safe guards (mostly relating to waste disposal).  I know that those safegaurds are technically feasible, and probably quite cheap to impliment.  But I strenuously object to people attempting to coopt concern for AGW as a mechanism to generate support for nuclear power.  (I have similar, but even stronger objections to coopting concern about AGW to push for negative population growth and/or negative economic growth policies by people who think those are intrinsically desirable in any event.)

    I want to see support for action agains AGW across all parties, whether green, socialist, centrist or conservative.  I am not going to tie support for that action to any secondary issue when they are not essential to solving AGW, even if they would be helpful. 

  13. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    JvD, the report you link shows that ~94% of those tax revenues come from oil. Conversely, oil accounts for less than 5% of global electricity generation. Basically... you are using gasoline tax revenues, which have nothing to do with electricity generation, to argue that fossil fuel electricity generation is not more expensive when subsidies are removed. Clearly false. The report also shows that ~46% of fossil fuel subsidies go to coal and natural gas, which are primarily used for electricity generation. Rounding that up we could say that roughly half of fossil fuel subsidies go towards electricity generation... while only ~6% of fossil fuel tax revenues come from electricity generation... and suddenly your 'eight times' is going in the opposite direction. That is, fossil fuel electricity generation gets about eight times as much subsidy support as it generates in tax revenues... based on your chosen data.

    Your other claims are similarly flawed. Many countries have been able to install massive amounts of renewable electricity generation (up to 100%) without any storage or long-distance transmission. These things will certainly be required in many countries, but not until the transition to renewable electricity is well underway (say ~50% of electricity generation)... by which point even the combined costs of renewable power and improved grids are expected to be significantly lower than fossil fuels.

    As to solar getting 75% subsidies in the US. Not even close. It's a 30% investment tax credit (dropping to 10% at the end of next year). At either $0.0387/kWh (with subsidies), or $0.0553/kWh (without), the lowest solar PPA prices in the US are now both lower than the national average price. That's more than 'competitive'. Indeed, the subsidized price is lower than any other power generation in the country... except the cheapest wind farms.

  14. Joris van Dorp at 23:58 PM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    To the moderator,

    It is no controversy that adding electricity storage to solar or wind adds at leasts 10 to 20 ct/kWh, making it grossly uncompetitive even with FF having fully internalised costs.

    http://www.sandia.gov/ess/docs/other/Grid_Energy_Storage_Dec_2013.pdf

    By the way, you can always just ask for a source for anything I claim. I never write anything not backed-up by solid evidence. I don't have time for such nonsense. I'll give evidence for all my claims freely, if asked. No need for threats! :)

    Moderator Response:

    [JH] If have neither the time nor inclination to document the sources of your statements, then this website is not for you. 

  15. Joris van Dorp at 23:42 PM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    @CBD: the fact that fear of nuclear is universal does not follow from nuclear's performance in terms of safety and environmental effects. Coal based power has killed millions of people, and still kills more people every day, globally, than nuclear has killed in its entire existance.

    My point is that the extraordinary fear of nuclear power is an irrational barrier to having nuclear solve AGW efficiently, which scientists should have spent some time removing in decades past. Instead, scientists have devoted all their attention to urging co2 emission reductions. In the upcoming climate talks in Paris, the focus will again be entirely on agreeing on reduction of global co2 emissions. No effort will be spent on agreeing to reduce global antinuclearism. I think this way of approaching climate policy has failed in the past and it will continue to fail in Paris and beyond.

    You repeat that solar and wind are cheaper than nuclear. Could you explain briefly how solar or wind can ever be cheaper than nuclear on a cloudy, windless day?

  16. Joris van Dorp at 23:16 PM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    CBD: "If even just the overt subsidies, to say nothing of the massive 'external costs' from their health and environmental effects, were withdrawn fossil fuels could not compete with solar and wind power now."

    That is incorrect. Fossil fuel tax revenues dwarf fossil fuel pre-tax subsidies in a ratio of 8 to 1.

    http://www.oecd.org/env/49090716.pdf

    In other words, fossil fuel usage brings in eight times as much tax revenue (in OECD countries) as it takes in subsidies. It is only the external costs (mostly climate impact costs) which can push the cost of fossil fuel energy above the cost of unbuffered(!) solar and wind power.

    That said, buffered wind and solar power (buffered as in: made fully dispatcheable by adding electricity storage and long-distance transmission) is still far more expensive than unmitigated FF, even including FF external costs. That is a serious issue not to be ignored. It implies that relying on solar or wind to replace global FF use will require their permanent financial subsidies, globally, so better make sure the money for that is made available - globally - if we intend to go that route.

    Finally, recent record-breaking PPA's for solar and wind in the US still benefit from exorbitant tax benefits and subsidies, equivalent to up to 75% of their base cost, so these impressively low PPA's do not nearly imply that solar or wind are competitive with FF.

    Moderator Response:

    [JH] Youcontinue to make unsubstantiated global asertions, e.g.,

    That said, buffered wind and solar power (buffered as in: made fully dispatcheable by adding electricity storage and long-distance transmission) is still far more expensive than unmitigated FF, even including FF external costs. 

    Unsubstantiated global assertions such as the above are nothing more than sloganeering which is prohibited by the SkS Comments Policy. Please cease and desist immediately.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive or off-topic posts. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site. 
     
    Finally, please understand that moderation policies are not open for discussion.  If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

  17. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Are there any proposed bills in any government body anywhere in the world calling for a halt to all production of ff-burning machines, vehicles, buildings and plants by the year 2018?

  18. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    JvD, yes the high cost of nuclear power is largely due to safety measures... which are required due to fear of meltdowns... which exists because the nuclear power industry cut corners and continued using outdated plant designs (e.g. Chernobyl) and old reactors (e.g. Fukushima) long after they should have been abandoned.

    However, the only thing that matters is that they are expensive. Why that is the case would only be relevant if there were some realistic way of changing it in the immediate future... which there isn't. Yep, without Three Mile Island, Chernobyl, and Fukushima the whole world would very likely be running on relatively cheap nuclear power by now. But that isn't the reality we live in. Every time nuclear power could have really started to take off and become competitive there has been a disaster and the technology has instead fallen further behind.

    Now that it has reached the point that wind and solar are both cheaper than nuclear there is no chance that current commercial nuclear power designs will ever become a major contributor. None. Maybe some new technological breakthru will make some form of nuclear financially viable again in the future, but until then nuclear isn't going anywhere.

  19. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Tom Curtis, I disagree that 'we have not seen any major turnaround in the US'. US CO2 emissions per capita peaked at 22.51 metric tons in 1973 and were down to 16.3 in 2012. Yes, that is still higher than most countries (though not Australia), but a 28% reduction (most of it in the past several years) seems like a "major turnaround" to me. Similarly, total US CO2 emissions peaked at 5.928 billion metric tons in 2007 and were down to 5.181 billion in 2012... a 13% reduction in five years.

    The world record for lowest cost solar power purchase agreement has been broken twice in the past month... both for new plants in the US southwest. Wind and solar power generation have tripled in the US since Obama became president. Average fuel efficiency of US vehicles is rising rapidly. Et cetera. There are a lot of different indicators showing that the United States has turned the corner on carbon pollution. Certainly still a long way to go, but the US has been heading in the right direction for several years now.

    As to when we will see a global transition... I don't think it will have as much to do with the '100th monkey' as with the financiers. At this point, the only reason fossil fuels are still hanging on is that they've got powerful financial lobbies behind them. If even just the overt subsidies, to say nothing of the massive 'external costs' from their health and environmental effects, were withdrawn fossil fuels could not compete with solar and wind power now. By 2020 they won't be able to compete even with the benefit of subsidies. That situation is not sustainable. The political favor which is propping up the fossil fuel industry is purchased via campaign contributions and lobbiests. As fossil fuel profits continue to get squeezed (as oil profits are currently being squeezed like never before) the money available to buy that political favor will decline... just as the money available for wind and solar companies to do the same increases. Renewables have already started to receive some of the favorable treatment previously enjoyed by fossil fuels. That will only snowball as each benefit to renewables pushes fossil fuels further and further behind. In the end, I expect a rapid collapse of fossil fuel financial and political influence. At which point, the misinformation campaign will also stop and the '100th monkey' will realize that they believed in global warming all along... because the people telling them what to think will then be getting their money from 'big renewable'. No way we aren't in the midst of full scale global conversion to renewable power before 2030 unless some major new technological breakthru comes along with a less expensive alternative.

  20. Joris van Dorp at 22:03 PM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Tom, are you suggesting that solar and wind power are more likely to eliminate global coal burning than nuclear power, and hence that scientists have been right to focus on the need to reduce co2 emissions rather than the need to remove irrational barriers to nuclear deployment?

    I'm not sure I understand what overarching point you are trying to make here.

    Concerning wind in Europe, it is clear that onshore wind in Europe tends to be costly, not so much due to the cost of the technology itself, but due to the cost of NIMBY and the high cost of land, which is getting worse because many of the best locations have already been tapped. But yes, there has been a kind of 'demonisation' of onshore wind energy growing in Europe. The concern is not so much the result of a misunderstanding of safety issues as with nuclear (although there have been a few horrific fatalities in the wind industry in recent years, which briefly made headlines), as it is the high cost of subsidies, the spoilage of views, the bird and bat mortality, the emerging issue of the financial and environmental cost of the additional powerlines needed, and the particular noise polution caused by the turbines. A number of European countries have recently shut down subsidies for onshore wind for this reason. All in all, I don't think it is difficult to understand why onshore wind is a bit more expensive in Europa than in the Asian pacific region. It's probably not about irrational demonisation as is the case with nuclear.

    Moderator Response:

    [JH] Please tone down the rhetoric and avoid unsustantiated global assertions. 

  21. 2015 SkS Weekly Digest #27

    Michael Fitzgerald @47.

    I concur with your first sentence. However, addressing these three logical outcomes from your '239-Steps' test is made difficult by your apparent denial of the snowball Earth mechanism ('apparent' in that I am left to interpret the moderation "(snip)" @47).

    And in addition to that apparent difficulty, I do not concur with your second sentence. Why do you write that I "seem to believe that no reasonably supportable function consistent with a sensitivity of 0.8C per W/m^2 at an average surface temperature of 288K exists."? My comment @40 surely suggests the exact opposite.

    In the round, your comment @47 simply re-states your problematical 239-Steps test in a different form. I'm not sure how that would be any help to 'man nor beast'.

    Within all your inconsequential/nonsensical blather @47, I note you tell us "170K ... below which the feedback is zero". On what do you base that assertion?

  22. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    JvD @20 & 21, I notice from page 17 of the report that onshore wind costs more in Europe than in the Asian countries.  Is this also because of the "demonization" of renewables in Europe?  Apparently that is "the only credible explanation" in this sort of case.

    What is noteworthy is that while the values I quoted are for studies of historical, actually operating plants, the values from the various bar charts are for Gen III nuclear plants; and include a carbon price of $30 a tonne for coal.  The report feels it is necessary to report that " that there are great uncertainties concerning
    the cost of carbon capture, which has not yet been deployed on an industrial scale" but feels no need to report similar uncertainties on the price third gen nuclear reactors, which have also "not yet been deployed on an industrial scale".  The important point, however, is that the bar charts you are rellying on do not reflect historical values and hence are irrelevant to the point I made.

  23. Joris van Dorp at 20:19 PM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Page 19 of this IEA publication clearly shows that nuclear is far cheaper in asia-pacific countries than in the USA.

    https://www.iea.org/publications/freepublications/publication/projected_costs.pdf

    The only credible explanation is the high cost of rabid antinuclearism in the USA and other countries.

    My point is that scientists have spent too much time urging humanity to stop emitting co2, while failing to urge humanity to stop being antinuclear.

    Moderator Response:

    [JH] Unsubstantiated and argumentative assertion stricken. Please cease and desist including statments like this in your posts.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

     

  24. Joris van Dorp at 20:14 PM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Tom, I believe you are mistaking cause for effect. Demonisation undermines public acceptance of nuclear, which increases the cost of nuclear (the extreme 'negative learning curve' of nuclear as seen in antinuclear countries). In China and other non-antinuclear countries, the exact same nuclear power plant costs only half as much as in antinuclear countries like the USA. Public acceptance is the cause of this difference. Cost is merely a symptom of public acceptance.

    By the way, the 'nuclear is too expensive' argument seems contrived, because solar and wind energy are even more expensive than expensive nuclear. Yet popular 'green' mythology holds that we can solve the climate crisis with wind and solar, never mind the cost. It seems one can't disparage nuclear over cost issues while hailing far more expensive solar and wind as the end-all and be-all of climate protection, no can one?

  25. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    JvD @18, what has kept the world from nuclear has not been demonization but the simple fact that its levelized cost is greater than that of coal (see table 11.1a):

    Nuclear

    LCOE $/MWh 74 56-67 44 51-77 33-74 71

    Pulverised coal
    LCOE $/MWh 47 45 51 36-44 28-75 51-53

  26. Joris van Dorp at 18:02 PM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    If nuclear power hadn't been demonised so successfully, the world could have had a decarbonised electricity supply by now.

    http://www.researchgate.net/publication/270572988_Global_zero-carbon_energy_pathways_using_viable_mixes_of_nuclear_and_renewables

    http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0124074

     

    http://conservationbytes.com/2014/12/15/an-open-letter-to-environmentalists-on-nuclear-energy/

    SKS is a very popular climate science website, and rightly so, but in all the years I've followed this website, I've seen a lot of talk about renewables as a solution to AGW, but almost nothing about nuclear. Indeed, whenever nuclear has come up, it has been attacked and disparaged. That is a pity, because as this article shows, it is now almost too late to prevent 2C of warming.

    I wonder if the decades of antinuclearism which has prevented nuclear power from achieving global hegemony instead of coal could not have been prevented if scientists had spent a little less time advocating for people to reduce co2 emissions, and a little more time on explaining to the public that nuclear power is in fact a bona fide and effective way to achieve credible climate protection, let alone elimination of air pollution from electricity generation.

    P.S. (I have been banned from this website (which I greatly value) for years now, for being a determined pro-nuclear advocate. My first account was "JvD". I hope that re-registering under a new account is acceptable, since I've spent so much time being banned in penance. If not acceptable, please excuse me and just ban this account as well. Thank you.)

  27. Global warming is causing rain to melt the Greenland ice sheet
    Another paper linking the 2012 event to an atmospheric river (among other causes) is Neff(2014) doi:10.1002/2014JD021470
  28. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Whilst I agree with the article and it's undoubtedly gloomy and likely conclusions, there is a form of Carbon Capture which is gaining traction all over the world which I have never seen on this forum, - not that I read the majority of articles, - however, I am referring to Terra Preta, now usuallly called Biochar, which is the practice of mixing charcoal with compost and using this as compost.

    The charcoal part of this mix remains in the soil with the nutrients from the compost and makes the goodies available to plants (becomes 'Permanent Compost' whilst also acting as nurseries for huge populations of soil biota, which also stimulate the plants.

    This has two major effects, one the carbon is sequestered for huge periods of time,- Terra Preta paddocks in South America have had the charcoal measured to be there 7000 years- those paddocks contain 30% charcoal down to 1 metre, in fact it has been calculated that if all the tropical areas of our planet went over to Biochar we would remove all the carbon dioxide added by industrial development since 1800 whatever, - although I have not seen how long estimated.

    Nontheless it is a significant thought.

    The second major effect is the increased, often spectacularly increased soil fertility, which adds a significant element/motivation, economics, ie you make money with it, very hard with CCS

    Less major effects include greatly increasing the water retention ability of the soil, and locking up most toxins in the soil.

    The point is that the Biochar movement is significantly growing all over the world, almost all using waste carbon, which would otherwise have returned to the air and much of it happening at grass roots level and it is a message of hope, whereas requiring the rich and powerful to make the required sacrifices seems to me to be a hopeless.

  29. 2015 SkS Weekly Digest #27

    Moderators - Take note, there may be a sockpuppet in action. 

    Michael Fitzgerald, you are either co2isnotevil/George White, whose views on this site were shown to be nonsense years ago, or you are parroting his views without credit.

    Your last post with "..1.6 W/m^2 of surface emissions per W/m^2 of net solar input..." directly echos many co2isnotevil SkS posts both in phrasing and in claims about short climate response, and both your phrasing "...incremental solar input..."  and arguments here directly match a July 3rd 2015 co2isnotevil post at WUWT

    ---

    Your math is IMO utter and complete nonsense - 4.4*239 is a meaningless and unphysical multiplication, 255K is only of interest as the emissions of a perfect blackbody radiating 239 W/m2 (ie in Gedankenexperiments), while the Earth is a real graybody where emissivity throttles radiative output to space, you confuse cause and effect (TOA imbalances from emissivity or albedo changes lead to changed surface temperatures that can once again radiate the same as incoming - you have the temperature change coming first), Snowball Earth is a red herring in regards to current climate change, etc etc. Nonsense on top of nonsense, complicated arguments without basis that seem (IMO) intended to dazzle and confuse, not science. 

    Moderator Response:

    [RH] Looking into it.

  30. MIchael Fitzgerald at 11:36 AM on 15 July 2015
    2015 SkS Weekly Digest #27

    Moderator (RH)

    You should also remove 2) from post 41) where snowball earth was originally brought up.

    Thanks.

    Moderator Response:

    [RH] The issue is that you're making up your own theory how snowball earth events play out, on the fly. Tom's reference is well substantiated by a great deal of research on the subject.

    Update: Specifically, your explanation doesn't explain cap carbonate deposits. There's a whole website dedicated to snowball earth science at snowballearth.org.

  31. MIchael Fitzgerald at 11:33 AM on 15 July 2015
    2015 SkS Weekly Digest #27

    Moderator (RH)

    Thanks for the reference.  One error is defining the current steady state as the zero feedback result.  The 1.6 W/m^2 of surface emissions per W/m^2 of net solar input must be after feedbacks have been accounted for, otherwise more than 1 W/m^2 per W/m^2 of input violates COE. This is also a multi-decade to multi-century average that varies little from year to year going as far back as we have accurate records, so certainly any feedback that operates on time scales of decades to centuries must alreadly be accounted for in the steady state average and this includes GHG, cloud and weather related feedback.

    It's also interesting that the steady state average includes seasonal transitions which, relative to surface reflectivity from ice and snow, emulates the transitions in and out of ice ages, albeit on a much shorter time scale.  Another test could be crafted to more precisely calculate the most predominant non GHG related component of temperature changes between ice ages and interglacials based on seasonal differences in the response to solar input (i.e. feedback from growing/melting ice/snow).

    The incorrect quantification of feedback didn't seem to affect the specific analysis (I didn't dig too deep), but the sensitivity claimed was 3 W/m^2 per K, which in the units used by the IPCC is a sensitivity of 0.33 K per W/m^2 which is below the IPCC's lower bound of 0.4C per W/m^2 and approximately equal to the SB sensitivity at the planets emission temperature of 255K.

  32. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    The essential point is that the exisiting infrastructure of industrialized civilization irreversibly uses fossil fuels at a high rate, so produces greenhouse gases at a high rate. That is the situation now. Policies to reduce the usage of fossil fuels can only slow down the rate of emissions slowly. The current atmospheric concentration level is 400 ppm and this will continue to increase even as the rate of emissions decreases. The continuing absorption of emissions in the oceans will only slow down the global atmospheric warming but at the expense of the damaging acidification of the oceans. Limiting the warming to 2 deg Celsius is not  feasible even if policies are adopted to reduce the rate of fossil fuels as rapidly as practical.

  33. MIchael Fitzgerald at 10:34 AM on 15 July 2015
    2015 SkS Weekly Digest #27

    PhilippeChantreau, #43

    There's no double standard.  I expect the same degree of rigor from others about anything having to do with science that I expect of myself.  Anyone can assert a hypothesis, but scientific rigor is all about asking questions and testing those hypotheses.

  34. MIchael Fitzgerald at 10:25 AM on 15 July 2015
    2015 SkS Weekly Digest #27

    MA, Tom #40 #41

    It seems that both of you understand the contradiction this test exposes which can be resolved by either finding a way to disqualify the validity and applicability of the test, identifying a function of sensitivity that when the test is applied, produces the correct results or accepting a lower sensitivity. You both also seem to believe that no reasonably supportable function consistent with a sensitivity of 0.8C per W/m^2 at an average surface temperature of 288K exists. Let me address the potential issues you've raised towards disqualifying the applicability of this test.


    Snowball Earth is not a stable state, for if it was, we would still be in it. The most likely events to initiate it would be a large impact event or the explosion of a super volcano that happened to coincide with a natural ice age. Once the dust settles, the planet will warm back up. Of course, this requires that the Earth respond to changes in solar input much faster than currently accepted, as the dust will only persist for a decade or so. A less likely cause would be a dramatic decrease in solar output.

    (snip)


    Hysteresis is not evident in the response to more than a 100 W/m^2 difference in total forcing between summer and winter. If it was, we would see different delays between min/max solar input power and min/max temperature and/or different average temperatures as the planet warms vs. as the planet cools. Delay can masquerade as hysteresis, but the two are not the same. To mitigate the effects of delay on the test, after each step of input, a long enough time must pass for the planet to be in LTE with respect to the total input power. To the extent that feedback from increasing or decreasing reflection changes the input power, the pre-reflected input power will need to be adjusted until 1 W/m^2 of input after reflection (forcing) is received in LTE. This isn't a problem since forcing, per the IPCC definition, already excludes input power reflected away by the dynamic actions of surface ice/snow and clouds.


    The ice cores show that entering an ice age is somewhat slower than exiting one which could be an indication of a small amount of hysteresis. This is more likely the consequence of less snow consequential to reduced evaporation as the planet cools and more rain consequential to increased evaporation as the planet warms, resulting in asymmetric rise/fall delays. As an avid mountaineer and back country skier, I can assure you that nothing erodes surface ice and snow faster than rain. If enough time is allowed to pass and TSI remained constant, the same LTE surface temperature will eventually arise whether TSI was increasing or decreasing prior to being held constant, although the time it takes to achieve LTE may be different. Keep in mind that the LTE surface temperature is the time weighted average of all possible metastable states consistent with the current accumulated forcing.

    The relative temperature range that the Earth experiences is quite large when you consider seasonal variability in monthly average temperatures which are about 250K at the poles and about 320K in the deserts. The only gap is between 170K and 250K, below which the feedback is zero and we can reasonably assume a linearly interpolated temperature dependence of unit (zero feedback SB) sensitivity at 170K up to the required sensitivity at 250K. We can also reasonably assume a monotonically decreasing sensitivity with temperature unless positive feedback as a function of temperature can be shown to increase at a high enough rate to provide significantly more than the 4.5% additional emissions consequential to a 1.1% increase in temperature arising from a 1% increase (3.9 W/m^2) in total forcing (baseline 390 W/m^2 @ 288K with a sensitivity of 0.8C per W/m^2).

    The assertion that there's no baseline reference for the sensitivity as a function of temperature is not correct. The slope of the SB Law precisely quantifies the sensitivity for the zero feedback case, positive feedback increases the sensitivity above this and negative feedback decreases it below. By extending the ideal black body analysis we can establish hard bounds for an ideal gray body where the absolute effect can vary based on the specific physics describing how a layer between the surface and space reduces the emissivity. This range has an upper limit quantified by the slope of SB at the radiating temperature of the planet and a lower limit quantified by the slope of SB at the radiating temperature of the surface whose emissions are attenuated by the emissivity. The accuracy and precision of the ideal black body result is limited by the precision of the SB constant, while that for an ideal gray body is limited by the precision and accuracy of the emissivity.

    If Earth behaved as an ideal gray body, we could bound the sensitivity at 0.25 +/- 0.05 C per W/m^2 (0.3C per W/m^2 is the sensitivity at the radiating temperature of 255K and 0.2 C per W/m^2 is the sensitivity of a surface at 288K). This represents only 20% uncertainty as compared to the 50% uncertainty of the currently accepted estimate of about 0.8 +/- 0.4C per W/m^2. Unfortunately, there's no overlap in these two estimates, so more testing is required.

    Determining if the planet behaves like a gray body and how close to ideal this behavior is can be ascertained by plotting the average surface temperature on one axis vs. the average power emitted by the planet the other. From this, we can establish how close the real behavior is to the ideal behavior of a gray box quantified by Stefan-Boltzmann with an emissivity of about 0.61 (239 W/m^2 @ 255K / 390 W/m^2 @ 288K). This seems like a simple enough test, does anyone have an idea about what it will tell us when applied to satellite data? Has anyone done this?

    Moderator Response:

    [RH] Unsubstantiated snowball earth theory removed as sloganeering until such time you provide a published citation supporting it.

  35. MIchael Fitzgerald at 10:10 AM on 15 July 2015
    2015 SkS Weekly Digest #27

    KR #42

    I've already considered the analysis based on current conditions and the situation doesn't get any better. If 1 W/m^2 of forcing (incremental solar input after reflection) results in a 0.8C temperature increase, the Planck emissions increase by 4.4 W/m^2 from 288K to 288.8K. All of the W/m^2 of input are subject to the same conditions, thus each W/m^2 of input must also result in 4.4 W/m^2 of Planck emissions (how can it tell which watt is which) and results in a total of 4.4*239 = 1051.6 W/m^2 which corresponds to a temperature of about 96C. Clearly this can't be true.


    Didn't Milankovitch postulate that the asymmetric response to forcing by the hemispheres interacting with the precession of perihelion had the effect of variable gain, thus apparent amplification?

    It also seems to me that the sensitivity has a discontinuity at 0C, since the negative feedback from incremental reflection by clouds is absent because surface ice/snow has about the same average reflectivity as clouds, thus below 0C the net feedback is more positive. This would imply that as more of the surface is covered by ice and snow, as it is during ice ages, the average sensitivity is higher.

    Moderator Response:

    [RH] If you're interested, SoD has a very good three part series on measuring climate sensitivity that you might find interesting.

  36. Global warming is causing rain to melt the Greenland ice sheet

    Recommended supplemental reading: 

    Greenland is Experiencing a Sudden and Rapid Melt Season Onset by Pakalolo, The Daily Kos, July 9, 2015

  37. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Fortunately China is working its toosh off converting to renewable energy.  Her rate of construction of new fossil fuel plant is going down rapidly and she seems to always exceed any promises in this regard that she makes.  Her motivations are not just climate change which will impact on her very hard.  She doesn't want to be caught by the short and curlies, dependent on overseas energy.  I wish the US of A would follow suit.  Without sorting out PPCT, she never will.

    http://mtkass.blogspot.co.nz/2015/01/ppct.html

    Moderator Response:

    [PS] link removed.

  38. Global warming is causing rain to melt the Greenland ice sheet

    And part of the reason is that we just had the warmest June on record.

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

  39. Rob Honeycutt at 04:00 AM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    On a personal level, here is something I tell people that relates to stranded assets: Carefully consider your next vehicle purchase.

    If you buy a big, gas guzzling SUV as your next new car, there is a strong likelihood that you will get next to zero resale value when you want to trade it in. Potentially that's true for many ICE vehicles as prices fall for EV's and their availability expands.

    It'll be curious to watch what happens in the vehicle leasing market as the shift occurs. This could rapidly become a massive liability for those leasing companies.

  40. Rob Honeycutt at 03:49 AM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Tom... Unfortunately, changes in social norms are unpredictable and erratic. That's the achilles heel to all the projections: How and when humans will actually respond suficiently to the challenge.

    It's seems to me our response is going to be a little like the 100th monkey effect. At some point there will be a shift where people, en mass, will accept there is a problem and respond. Depending on when that actually occurs will dictate how rapidly the response is required. 

    I guess I just have a hard time imaging that in 2050 there are going to be very many people running around saying there's no problem. I think denial has its limits.

    It also bears acknowledging, there a lot of positive things happening. Wind and solar are being built out at a rapid pace, and their costs continue to fall. The auto industry is showing great progress in shifting toward electric vehicles, with nearly every major company launching EV's in the coming years. This past year was the first year we saw carbon emissions decouple from economic growth, which was something many said was impossible. 

    It's definitely not enough and not fast enough, but these are the things that have to happen, and they are happening. 

  41. 2015 SkS Weekly Digest #27

    Tom Curtis - Quite right, I must have been conflating AR4 and AR5, as you correctly point out that the IPCC didn't give an AR5 median/mode. 

    As it stands, the 1.5C lower sensitivity bound given in AR5 (as opposed to the 2C lower bound in AR4) is due almost entirely to the incorporation of short-term observational estimates such as the recent Lewis paper - and there are serious indications that such short-term estimates are biased low. I therefore consider (IMO) the AR4 bound of 2C on sensitivity (only a 5% chance of sensitivity being lower than that given current data) to be a more reasonable estimate. 

    Either way, the only 2% change in sensitivity to direct forcing over a +/1 5C range around current conditions is really negligible considering the uncertainties in feedbacks, and dispite Michael Fitzgeralds search for exactitude in that sensitivity delta it's just insignificant compared to the feedback uncertainties. 

  42. 2015 SkS Weekly Digest #27

    KR @42, the IPCC likelihoods for 1 C and 6 C show they still have a fat tailed probability density function for the climate sensitivity.  It follows that their most likely (modal) value is less than 3 C, although it is possible (but not certain) that the most policy relevant value (the mean) is above 3 C.  Unfortunately in AR5 they specified neither mode, median or mean of their implicity PDF.

  43. PhilippeChantreau at 02:42 AM on 15 July 2015
    2015 SkS Weekly Digest #27

    Michael Fitzgerald at 38. This is the weekly digest, there is flexibility as to what's on topic, as was pointed to my attention recently.

    My question is essentially why the egregious double standard? Why such heavy scrutiny and such high burden of proof on climate science, and why so little scrutiny and so little burden on other activities that have proved for sure how damaging they are. You ask a specific question indeed. My contention is that the question is misplaced, and that areas of activity with a proven track record of economic damage deserve at least as much questioning. You may not want to engage, and mods may decide it is OT, but it is a perfectly legitimate argument.

    I think I agree with your take on precautionary principle. There is no reason why it should apply only to climate science and decisions made on its basis.

  44. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Rob Honeycutt @10:

    "I feel fairly confident that humanity will be at or near zero carbon emissions by 2050"

    I wish I shared that confidence.  I think it is still at least an even chance that emissions in 2050 will be greater than current emissions.  I don't expect the climate denial disinformation machine to pack it in anytime between now and 2050, and neither have we seen any major turnaround in the US, Australia or India that would lead to confidence of achieving zero emissions by 2050.

  45. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    ranyl @8, the IEA Outlook says:

    "In its latest report, the Intergovernmental Panel on Climate Change (IPCC) estimated that to preserve a 50% chance of limiting global warming to 2 °C, the world can support a maximum carbon dioxide (CO2) emissions “budget” of 3 000 gigatonnes (Gt) (the mid-point in a range of 2 900 Gt to 3 200 Gt) (IPCC, 2014), of which an estimated 1 970 Gt had already been emitted before 2014. Accounting for CO2 emissions from industrial processes and land use, land-use change and forestry over the rest of the 21st century leaves the energy sector with a carbon budget of 980 Gt (the midpoint in a range of 880 Gt to 1 180 Gt) from the start of 2014 onwards."

    For comparison, 3 000 gigatonnes of carbon dioxide is 817. 4 gigatonnes of Carbon, ie, about 20% less than the well known target of a trillion tonnes of carbon.  More to the point, the energy sector target shown in the diagram above represents 980 GtCO2, or 267 GtC.  These are figures based on the latest IPCC report, and hence are hardly "fictitious".  Further, they are figures for a 2 C target.

    More importantly, these figures represent emissions, not CO2 concentrations.  The target scenario stabilizes at a CO2 concentration of 450 ppmv.  That represents 360 GtC (1320 GtCO2) above preindustrial levels.  In contrast, 592 billion metric tonnes of CO2 represents an atmospheric increase of 76 ppmv (ie 356 ppmv total concentration); and a total increase of 900 billion tonnes represents 116 ppmv, for a total target of 396 ppmv.  That means if we accept the, presumably non fictional values from the quote from the article linked by JH we have already exceeded the target for 4 C; and that the climate sensitivity is 2.1 C per W/m^2, or 7.8 C per doubling of CO2.  

    I think such a prediction as the central estimate (50-50 chance) can safely be described as alarmist.  

    Rather than the scientists at the conference being so alarmist, it is more likely that David Biello is massively mistaken about what the scientists said.  (Most likely he has mistaken emissions for CO2 content in the atmosphere).

  46. Rob Honeycutt at 02:09 AM on 15 July 2015
    A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    I'm with CBDunkerson here. Anyone investing in carbon emitting infrastructure is making a massively risky investment... Not even a risky investment, they're making an investment that is not going to return a profit. 

    Think about what's likely to happen over the course of the next 40 years. We are certain to see more and more extreme weather events. We're going to see more and more of exactly what scientists have been saying all along. It's going to become abundantly obvious, far beyond what it is already, that we have big trouble on our hands. 

    At some point it's not a question of who's going to make the decision to shut coal plants down. It's going to be, how fast can we shut them all down, and how much disruption are we going to see from the shut down?

    I feel fairly confident that humanity will be at or near zero carbon emissions by 2050, one way or another. What I'm not certain about is whether we can do it in a methodical, systemized fashion designed to produce the least impact to people and economies.

    What I think the world's capital investments (specifically, the world's capital investments in carbon production and use) are doing is pushing us toward a chaotic transition.

  47. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    Actually, I'm with TomR on needing an explanation of the 'replacements clause'. As worded, it would appear to indicate that we could continue replacing existing old coal plants with new ones indefinitely and never hit 2C... so long as we stopped building 'non-replacement' carbon commitments by 2018. Which is certainly false and thus presumably not the intent.

    Also, the 2018 figure is based on an assumption that any new carbon emissions sources will continue operating for their expected lifetime. I suspect that is unlikely to be true for many. In the US we have already seen coal plants being shut down prior to normal end of life because it has become more cost effective to build and operate new natural gas plants than continue running some old coal plants. As solar and wind power costs decline we are likely to see a similar result... with both coal and natural gas plants shutting down early in favor of cheaper renewable power. Indeed, the likelihood of fossil fuel plants becoming such 'stranded assets' is already causing a decline in investment in these technologies.

    The point at which CO2 emissions must peak to meet the 2C target is inherently a factor of both total emissions up to that point and rate of reduction afterwards. Until we have some kind of handle on what rate of reductions is likely to occur it isn't possible to define 2018 or any other year as the 'necessary peak year'.

    Moderator Response:

    [JH] I have asked the author of the OP, Stephen Leahy, to chime in on this issue. 

  48. 2015 SkS Weekly Digest #27

    Michael Fitzgerald - Given the various non-linearities along the range, I feel that it's really not useful to step from zero forcing to present conditions in order to establish slopes. Rather, since we're interested in how things will change from present conditions, look at the sensitivity to changes from the current conditions. 

    Rounding values just a bit for discussion, the sun provides 240 W/m2 of input energy, and in steady state the Earths climate will emit an equal 240 W/m2 to space at the top of the atmosphere. 

    From the Stephan-Boltzmann relation, P = emissivity * SB * T4, and rearranging for the effective Earth gray-body emissivity at 15C:

    240/(SB_constant*(15+273.15)^4) = emissivity is 0.6139

    Emitting 239 W/m2, ie with a 1 W/m2 forcing, and the effective emissivity becomes 0.6139 * 239/240 = 0.6114. The temperature required to emit 240 W/m2 with that new emissivity is (240/(0.6114*SB_constant))^0.25-273.15 = 15.30094, so the temperature sensitivity to forcing at current conditions is ~0.301C per W/m2

    This matches well with the predicted direct forcing of a doubling of CO2, 3.7 W/m2 leading to ~1.1C warming, with feedbacks expected to amplify it to ~3C. 

    Now calculating that sensitivity for different bounding scenarios, an ice age (~10C global average temperature) and an Eemian hothouse (~20C global average temperature, no polar caps, oceans 10s of meters higher), while retaining absurd precision:

    • At 15C, 1W/m2 leads to 0.30094 C temperature change
    • At 10C, 1W/m2 leads to 0.295718 C temperature change
    • At 20C, 1W/m2 leads to 0.306162 C temperature change

    The difference in temperature sensitivity per forcing watt between an ice age and a hothouse is less than 2%, far less than any uncertainties in feedbacks, so I think we can essentially treat that change as negligible. We can assume that direct forcing sensitivity is a constant for the purposes of evaluating climate change. Beyond that range the best response may just be "Uh-oh." 

    ---

    A far more interesting question is the level of feedbacks to a forcing change, which as summarized by the IPCC is in the range 1.5 to 4.5C, most likely value of 3C, per doubling of CO2. 

  49. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    "To avoid global warming of as much as 4 degrees Celsius by the end of the century, the scientists suggested civilization has a total budget of 900 billion metric tons of carbon dioxide in the atmosphere, and the world has already added roughly 592 billion metric tons since 1780."

    From article @JH 5.

    So less budget than the fictious 1000billion Tom C's diagram shows for 4C.

    "The argument against CCS is strong. Critics, however, often overlook the fact that making steel and making cement—the fundamental substrates of all power plants, whether wind turbines and solar rooftops or new nuclear—spew copious CO2, as does making the fertilizer that has made more than seven billion humans on the planet today possible. If the goal is zero- or negative emissions, these emissions will have to be eliminated. The only proposal at present to do so is CCS."

    CCS is very expensive and reduces power plant efficiency even if powered by biomass.

    Although the carbon negative claims are theoretically possible, most massive biomass production production is heavily carbon emissions loaded due to industrial farming, land change, fertilizers (production), pesticides, processing and tansport, and if power plant less efficient you need more biomass to get the same power an therefore more potential conflict with food and biomaterials production.

    I'm with Tom R all carbon negative asap, and call for chances of avoiding serious stuff 1:20 chnace which is common level for medical practioneers to consider thngs safe, i.e. there is a less than 1:20 chance that the treatment doesn't actually improves things.

    If people keep contemplating a budget rather than a huge debt people will just do lots of fancy accounting and CO2 emissions will just keep on going up.

    And don't forget the mass extinction event, implying the earth ecosystem needs repairing quickly as well, making things like pesticides, synthetic fertilizers, pollution, e-waste, rare earth metals, mining, deforestation and anything associated with toxic waste production kind of not sensible either.

    Where do stand?

    Let face it people are more worried about Scotish MP's voting on fox hunting than all this environmental stuff.

    Someone recently said to me that they felt I had good points but prefered just to not take notice as it meant they just function in their lifes, which were hard enough without having to worry about enviromentlachange as well.

    For me the only way to turn things arround on a tupence (as needed) is for everyone to want to.

    But at present it seems everyone wants to maintain BAU at all costs, be it powered by fossil fuels or the alternative environmental and GHG associated energy production systems available; playing at being accountants and accountants can make anything look rosey if they try hard enough.

    Wonder how many more extremely extrem weathe revents in a row will be needed before cliamte change is a high priority for everyone and not just a political tool to say the right thing about and hope for the children that its all been hot air?

    Moderator Response:

    [JH] Excessive white space eliminated.

  50. A Hard Deadline: We Must Stop Building New Carbon Infrastructure by 2018

    John Hartz @5, Schellnhuber is good company indeed.  Thankyou.

    @6:

    In a previous thread I wrote:

    "[It] is quite obvious that if it is acceptable, in 2018, to replace existing houses or to build carbon neutral houses, then it is also acceptable to replace an existing house with two 50% carbon neutral houses; or to modify an existing house to halve its carbon emissions, and build a new house with just 50% of current emissions per house, and so on. In particular, each 1% reduction in emissions from national electricity generation makes room for further economic growth.

    Ergo, Stephen Leahy's formula sounds dramatic, it really represents only a formula for no more emissions growth from 2018. Rather than a cessation of emissions growth (and hence ongoing growth in CO2 concentration), what the world needs is the almost complete elimination of net anthropogenic emissions by 2050, and hence on the order of a 3% reduction in global emissions per annum. That is a doable target. Even with slow initial progression, a genuine attempt to move in that direction will allow very rapid strides in the near future. It is not, however, something on which we can delay - and each year that we delay - each year you win your struggle for inaction makes the cost of transition higher (because it must be more rapid), and the end benefit lower (because of increased global warming durring the delay)."

    Obviously, even in context I agree with TomR's interpretation.  As to his suggested strategy, I do not believe it is necessary or achievable as a globally averaged target.  However, if we are to limit emissions on a per capita basis, as is required by simple considerations of justice, Western societies, and their citizens individually must indeed go net carbon negative as soon as possible, or purchase unused per capita emission credits from the third world to make up any overshoot.

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