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Comments 1 to 50:

  1. Welcome to Skeptical Science

    I've done two calculations to determine the contribution to atmospheric CO2 from wildfires, compared with burning fossil fuels.  I did not include Volcanoes or other natural CO2 sources.  When I estimated forest density, I came up with wildfires producing 88 times fossil fuel CO2 production.  When I found pre-computed numbers, I found that wildfires and fossil fuel burning are comparable.

    Assuming that forest fires produce the same amount of atmospheric CO2 as burning fossil fuels, and the half-life of atmospheric CO2 being 500 years, even if the entire WORLD shut down all fossil fuel burning (impossible!), the reduction in atmospheric CO2 would take centuries. And, since making more than a 25 cut in global fossil fuel use is unlikely, we are in this mess for the long haul.  So, my questions to you are:

    1. What do you propose to realistically cut CO2 significantly?

    2. How long will it take to reduce CO2 levels to pre-industrial age amounts?

    Thank you in advance,


    Moderator Response:

    [RH] Changed all-caps to italics. Please avoid all-caps, per commenting policies.

    [edit] Also, please show us your calculations that estimate forest fires produce 88 times the CO2 as FF emissions. 

  2. How much does animal agriculture and eating meat contribute to global warming?

    Excellent post.

    The flow charts are a fantastic visualization of the ratios for various energy uses and related emissions. This really points to the core targets that Americans can work on for overall emissions reductions, and where they can make the biggest impacts.

  3. A Buoy-Only Sea Surface Temperature Record Supports NOAA’s Adjustments

    A big thank you to you both, Zeke and Kevin. This is really useful and not a surprise, given the work I know went into preparing ERSSTv4. I like it that you've now included a comparison with Argo data, which contradicts what some people have been claiming. I'll be referencing this article from time to time.

  4. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    RickG @31, unlike CO2, aerosols do not become well mixed in the atmosphere.  As a result the negative forcing in relation to US/European aerosols was largely confined to the North Atlantic region, while those from China are largely confined to China.  That is significant because there is evidence that the North Atlantic region is more sensitive to forcings than most other regions of the globe.  This is most obvious with the impact of the milankovitch cycles forcing the glacial cycle due to strong NH summer insolation despite near zero global forcing.  (Note, nearly all the major glacial ice sheets are associated with the North Atlantic.) 

    The upshot of this is that it is not a given that a given aerosol concentration over China will have the same masking effect as the same aerosol concentration over Europe/NA.  So while increases aerosol emission will mask some warming, it is difficult to determine how much.

  5. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    I wonder, with respect to the cooling period from 1940 to the mid 1970s, which masked actual warming due to sulfate emissions; are there any projections as to what increased sulfates in Asia may be masking?

  6. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    wili @28, no we have not.  The reason is that, with zero net emissions, CO2 concentrations in the atmosphere will be drawn as excess CO2 is taken up by the ocean.  This process is fairly rapid and occurs on approximately the same timescale as the rise in temperature from the Transient Climate Response to the Equilibrium Climate Response.  It follows that, with zero net emissions, temperatures will remain approximately constant, as shown in this graph from Matthew's and Weaver (2010):

    Although Matthews and Weaver show a constant or slightly declining temperature with zero net emissions, a more recent study (not to hand at the moment) has shown the possibility of a slightly rising temperature as well, although this is most probable with low ECS so the rise in that case would be gradual and restricted.  In any event, so long as we achieve zero net emissions before we reach 1.5 C, and possibly 1.9 C, we can prevent mean decadal temperatures rising above 2 C above the preindustrial average.

    That's the good news.  The bad news is that even continuing emissions as low as 5% of current emissions may (and certainly emmissions at 10% of current levels will) be enough to kick us into the constant CO2 concentration path (red line above).  In that case whether or not we exceed 2 C depends on whether the ratio of 2 C divided by current temperature above preindustrial is less than, or exceeds the ratio of ECS to TCR, which means even another 0.2 C rise will make us 50/50 to avoid 2 C at best.  Further, ongoing emissions at the 5% rate will in the long term (400 plus years) result in an ongoing gradual rise in temperature for up to tens of thousands of years into the future (or until we reach zero net emissions).

    Further, this analysis ignores the effect indicated @15 above.  That probably means we require slightly negative net emissions of CO2 to achieve zero net CO2eq emissions.  (Note, for the long term, multi-centenial temperature rise, it is zero net CO2 emissions that matter, not zero net CO2eq emissons, due to the relatively short atmospheric lifetime of WMGH gases other than CO2.)

  7. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    On feedbacks, see most recently this: GW will be faster than anticipated (because of methane feedbacks from lakes)

  8. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Here's another question to pose to Kevin Anderson (or anyone else who want to take a shot at it):

    Given the lag time for full equilibrium effects of CO2, and given that we have been emitting at by far the highest rates over the last few years and decades, and given that we are already at about 480 ppm CO2 eq...isn't it likely that we are already locked in to about a 2 degree rise over preindustrial times, even if we were to stop all further emissions today?

    (This is of course assuming that we won't suddenly come up with a way to massively sequester atmospheric CO2, and that there is not some massive, unknown negative feedback waiting in the wings to save us--the potentially massive and quick feedbacks all seem to be positive, and you could add those to my 'given's above.)

  9. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    @ 22,

      Yes: but that is the exact politics of the matter- "..what is an excessive amount?"

      You are talking about the invisible hand of free market theory that is of course corrupted by any, and all, form(s) of Government intervention. The difficulty you talk of is often referred to as being, "..when Governments pick winners!"

  10. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    @ 24, 

     This is the argument that makes 'baseload' power largely a myth. If the elite want bespoke industry that makes profits while they sleep then they need to find a way to subsidise it and at the moment it is done through the sheeple consumer being too distracted by Hollywood to care enough about their kids to complain about the externalities of a globally manifest 24 hour working day.

     The definition of 'efficiency' is worth looking at. Methodical thought implies that a problem is first well defined.

  11. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    michael sweet @16, methane decays as a function of the concentration of OH radicals in the atmosphere.  Therefore increasing the quantity of ozone (thus preventing the photodissociation of H2O) and of methane will increase the average decay time of CH4 (currently about 12.4 years to reduce to 36.8% of the original concentration).  NO2 decays by photodissociation, so the rate is controlled by insolation and hence is fairly stable (decay time 121 years).  In either case, the effect is that at a given emission rate, there will be a equilbrium concentration such that 63.2% of the concentration equals the emisisions of the decay rate.

    For NO2, that concentration is significantly greater than the current concentration, even if NO2 emissions were halved.  As a result sequestration to avoid increased forcing from NO2 will certainly be required.  Because of the high natural rate of CH4 emissions and short decay time, that is not necessarilly the case.  Therefore it is possible that sequestration will not be needed for CH4.  On the other hand, increases in arctic CH4 emissions as a feedback, in addition to ongoing agricultural emissions will likely require ongoing sequestration.  In neither case will sequestration need to continue in perpetuaty, only until atmospheric concentrations stabilize.  That, however, is likely to take more than 50 years for methane and several hundred years for NO2.

    Beyond those points, RustNeverSleeps @18 makes excellent points.

    I am not aware of any particular research on this.  It is just a point that follows logically from the difficulty in reducing direct agricultural emissions combined with the at least doubling of human population over the coming century (with consequent increase in the need for intensive agriculture).  It is, however, a point that can slip by unnoticed by treating all emissions as just CO2eq for emissions pathways.

    Finally, my final conclusion was not that a small multiple of sequestration made necessary by agricultural emissions will also sequester the emissions from an ongoing fossil fuel industry.  That is certainly not the case, and it is dubious IMO that even 50% of current fossil fuel use can be reconciles with net zero emissions by sequestration.  However, some small level of sequestration will be necessary regardless, and that small level can be increased to reduce overshoot at a slow rate.  We are still best of keeping that overshoot as low as possible. 

  12. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Digby Scorgie @22, the product of air transport is not air transport itself, but efficient transport of people and goods.  One of the cheapest competitors of air transport is sea transport (or rail transport, or blimp transport) and in some cases simply telecomunications.  Therefore, even if no adequate substitute for jet fuel can be found, there will still be reasonably prices substitutes for the actual services provided by modifying our social expectations or rapidity of delivery.  Indeed, much of the "expense" of converting to a low emissions economy is simply social inertia in the form of expecting the bundle of goods and services we currently have, ie, optimized for delivery using fossil fuels, to remain unaltered when we could instead optimize for delibery with renewables with no loss of utility.

    That leave aside the fact that jet fuel can be synthesized direcly from biological fuels, and/or jet fuel exhaust can be captured and sequestered, in either case providing a zero net emission substitute at far below infinite cost.  Indeed, I included these possibilities in my estimate of US$200 carbon price for complete subsitution (although early schemes in this direction may be more expensive).

  13. Heat from the Earth’s interior does not control climate

    Maark @41, you should more carefully read the post above as it contains enough information to refute your theory as is.  Further information is available here.  On top of that, the rate of spread over time at ocean ridges is well known by dating the ocean floor.  That rate of spread is in turn correlated with amount of magma ejected, and hence the rate of heat flux at the ocean ridge.  This data does not support your theory.

    Finally, looking at things differently, the key question is not the absolute rate of energy release from the interior, but the rate of change in that energy release.  That allows us to consider the direction of that change by considering the sources of geohysical heat, which are two fold: friction from tidal interactions, and heat from radioactive decay.  The later necessarilly decreases with time because the radioactive elements are in fact decaying, ie, becoming inert elements by various combinations of radioactive emissions.  The rate at which that occurs is slow, being dominated by elements with half lifes in the billions of years - but it is one way.  The process cannot reverse itself.  Likewise, over time tidal forces reduce as tidal friction moves the interacting bodies further apart.  Again this is very slow.  There is a slight possibility of variation in that different continental configurations will result in more or less tidal friction, and hence more or less geothermal heat from tidal forces.  As it happens, the current continental configuration represents a near peak for tidal friction, but that peak will have been declining since the closing of the isthmus of panama as Australia, South America and Africa continue to drift north (thereby reducing friction by opening up the gap to Antarctica.  In any event, any change form this will represent a very small fraction of total geothermal heat over intervals of 100s of thousands of years.

    There is simply no physical basis to think geothermal heat could be increasing on a global level, and if anything it will be declining, at a far slower than glacial rate.

  14. Heat from the Earth’s interior does not control climate


    Use the search option at the top of the page to search for informaton about 'Milankovitch Cycles'.

    Essentially cyclical changes in Earths orbit and axial tilt that cause small fluctuations in how much sunlight is received by different parts of the Earth at different times of the year.

    This provides a small warming and cooling impetus. This then is magnified by changes in CO2 levels in the atmosphere as the oceans warm and cool, changes in methane levels in different climates and expansion/contraction of land and sea ice, altering how much sunlight the earth reflects to space.

  15. Heat from the Earth’s interior does not control climate

    I will pose this as a question because I am not an advanced scientist, just a college student in some basic environmental classes. If the earth's record shows 7 cycles of heat/cooling in past 650,000 years, then we should ask what is the common factor in all of these events. It is possible atmospheric C02 was the source, but then humans were not the source of the C02. Another common factor was the Earth's core and its heat. It is simple to observe earth's heat on any day in winter in our North American climate. When I pour concrete I must keep the ground below the concrete from freezing. We construction workers pile hay or straw in the ground and in a couple of days it is unfrozen. Does anyone disagree that there is constant heat radiating up from the earth core? This is basic right?

    My hypothesis, after reading the very basics of plate techtonics, is that warmer plates move closer to the surface heating water and soil. It is a fact that the plates are constantly moving so shouldn't this be considered? Where could I find evidence from core drill temperatures? Are there records kept as in sea temperatures?

    Some arguments above negate the potential for core heat to radiate this strongly on the basis that the change in temperature would need to be drastic. But my science book is saying that if air temperatures increase just one degree the results are drastic. Well then if an area under the Atlantic 1,000- square miles warmed by 4 degrees and the ocean conveyor belt brought that warm water to the equator it would certainly affect our huricane season and El Nino. It would also affect the glaciers. This hypothesis is at least consistent with warming in the pre-human historic past.

    If you have a simple expaination I sincerely want to know before I embarrass myself in class. Thanks

  16. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Another example of how some scientists don't give the full picture (or even the correct one) is Schmidt's Carbon Brief interview where he gave completely inaccurate figures for US emissions, even praising them (claiming imaginary reductions). This leads to the notion that GDP can be decoupled from emissions, which I've read other scientists espouse. I've always felt that this idea is false as it likely didn't take into account exported emissions. This Monbiot article points to research that  there is no evidence that decoupling is taking place at all (and may even be the reverse). I think scientists are guilty of not thinking deeply enough about this stuff, even though they think deeply about their subject area.

    Anderson is absolutely right, IMO, to point to these failings of the scientific community.

  17. It hasn't warmed since 1998

    AJC1973 @366:

    1)  You seem very confused about trends and variation.  The point about the final point of data is that it tells you nothing about any other data point.  In contrast, the trend sums up information about all the data, and does so in a way that usefully informs you about the next likely datapoint (see video below).  People who only want us to look at the first and last datapoint are really cherry picking - trying to blind us to the truth by the carefull exclusion of data contrary to their narrative.

     (Further comments)

    2)  Words to indeed have meaning, and expostulating about that fact won't lead us to ignore those meanings.  Thus, here are the four most recent annual temperature records for the three major surface temperature records:

    Year_____: _1998, _2005, _2010, _2014

    HadCRUT4: 0.536, 0.544, 0.559, 0.567

    NOAA____: _0.63, _0.66, _0.70, _0.74

    GISS_____: _0.63, _0.69, _0.72, _0.74

    As can easilly be seen, in each case 1998 < 2005 < 2010 < 2014.  You want to say that 2014 = 2010, but that is not true.

    Probably you have been confused by people inaccurately talking about a "statistical tie".  That is because in each case 2005 lies within the uncertainty interval of 2010.  Therefore, given the data it is statistically possible that 2010 was actually the warmest year, but the nominal value (or the mean estimate) places 2010 above 2005.

    Note, this is not a 'statistical tie' (or worse, a case where 2010 is 'statistically indistinguishable' from 2005).  That is because there are years which may have been (given uncertainty) warmer than 2005, but which could not have been (given uncertainty) warmer than 2010.  Put another way, the probability that 2010 was the warmest year given the data is greater than the probability that 2005 was the warmest year.

    Note, the same can be said of the relation between 1998 and 2005, and 2010 and 2014.

  18. It hasn't warmed since 1998

    AJC1973 @366 : You will need to explain yourself more clearly ~ since your post [above] does not make much sense.

    Words ( even "Proffesor" ) can have meaning ~ but they need to be allied with commonsense thinking. Is the world warming . . . or isn't it? The evidence shows clearly that it is . . . and word-games cannot alter the physical reality of it all.

  19. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Andy @20: I look forward to that, thanks.

    Tom @21:  That makes sense; the tax must make fossil fuels more expensive than the next cheaper alternative.  The only problem I then foresee is when it costs an excessive amount to get the alternative introduced — as perhaps with synfuels for aircraft and ships.  Anyway, it will be extremely interesting to hear what Kevin Anderson has to say about this, because he doesn't think an MBI such as a tax will work.

  20. It hasn't warmed since 1998

    2 things... 


    using a trend as an answer as to why the current data doesnt matter is crazy. you cant say it doesnt matter look at the other 10 data points they lead to this...  obviously they dont if they did there would be no cooling trend... lets break it down.. this is like a straight a student someone who had got 10 straight A's but on the final got an F..  The Proffesor then grades accordingly.. but the student says no... you didnt take into account the "Trend" my grade should be reflective of the past 10 measurements... would that really fly?


    Also come on guys words have meaning.. you cant say that 2010 was the highest temerature on record, it was tied with 2005.  if 2005 was just as warm 2010 cant be higher... 

  21. There's no empirical evidence

    jl5501 - there are a number of approaches to this. On page 405 of IPCC WG1 (chapter 5),  you will find results of 9 studies with different methods summerized. The range of the ECS from these studies is still wide. Another recent study is discussed here. Accurately determining both past temperatures and particularly past forcings is not a trivial exercise.

  22. G R A P H E N E

    Graphene technology certainly does not - and can not - address the rapidly growing problem of population increase or the pressure this puts on the food supply required for their survival. However, it may provide clean water through its potential use as a membrane filter. Graphene technology is not claimed to be a universal panacea. It may slow but will not stop carbon emissions from a warming Arctic.

    Given the present state of technology, it is difficult to see graphene technology replacing aviation fuel with stored electric energy. On the other hand, pending this development, it is possible to replace fossil fuel with bio-fuel. Graphene does have potential to slow, possibly reduce, ocean acidification by reducing greenhouse gas emissions.

    The essay examines the potential for graphene technology to displace fossil fuel for electricity generation and storage, land transport and, eventually, on vessels now dependent on bunker oil for propulsion. It will be developed. If it is not, there appears to be no other candidate able to displace fossil fuels. The consequences of not displacing them may make large parts of the globe uninhabitable by our species.

  23. There's no empirical evidence

    jl5501 @301 : The answer to your first question is multi-faceted, regarding past influences. In the short-term viewpoint of recent centuries, the biggest factor is atmospheric CO2 (plus its feedbacks). In the longer term i.e. megayears, you will find large influence from the subtle shifts of interaction between the gradually changing cycles of the planet's orbital shape and inclination of the axis, as well as continental drift [affecting ice-related albedo].

    Go to this site's Home Page, and check out the various Climate Myths ~ and in particular, Number 14 which addresses the recent cycling of Ice Ages. The chart there may give you the impression that a new ice age might be "expected" in 10,000 years or so . . . but in the text you will notice that the next [natural] deep cooling from orbital/tilt interactions will be a weak effect . . . and so the next "due" Ice Age might well be (hypothetically) due in 30,000 years or longer ~ yet in reality ( and owing to the the recent high levels of human generated co2 ) that due-to-arrive Ice Age will be scotched by the present higher than natural CO2 in the air and by the warmed-up oceans and by the dissipating North Polar ice. So . . . a long, long wait for new ice ages . . . and an unpleasant time for the next few centuries, from the overheating of our planet.

  24. Discussing global warming: why does this have to be so hard?

    we are not playig nothing safe : humans are changing earth and that's a good thing, I like the scientific evolution of our society which makes us confortably discussing on the internet of possible climate in the future centuries. this is a huge progress and it can continue to evolve.

    BUT : it means we have to stop fighting for stupid questions. the most important problem is to have food, water, energy, houses.

    if we can produce and distribute that all other the planet, it will be good. clearly, the biggest fear is capitalism which makes all these things too expensive and forces us to work for silly reasons (and consume more and more CO2 for nothing !), much more than climate change which even with 4°C shouldn't imply wars and food problems because it will be very slow compared to our lifes.

    so fire the assholes which serve us of governement, and let's assist the climate change without fear.

    Moderator Response:

    [PS] Please take the time to review the Comments Policy and ensure future comments are in full compliance with it.

    You also make a number of eyebrow-raising assertions. eg "capitalism which makes all these things too expensive" and " 4°C shouldn't imply wars and food problems". If you are going to make assertions, especially contrary to mainstream thought, then you need to back these with supporting references.

  25. CO2 effect is saturated

    so, where is the answer to the article ?

    the curve relating the CO2 concentration in atmosphere and temperature of lower atmosphere ?

    it should be a simple thermodynamic equilibrium wich depends on absorption and emittance parameters,

    and yes even with 100% of CO2 the temperature would be finite (because of the Stefan-Boltzmann black body rule which says the irradiance depends of temperature in T4 : the more a body is hot, the more it cools itself by irradiating around)

  26. There's no empirical evidence

    We know that the climate was warmer in the geological past than it is now. What do we know of the factors ( particularly co2) that caused the decrease in temperature from the warmest time?

    From that, are we able to calculate how much the climate would be warming without human generated co2 emissions

  27. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Digby Scorgie @19, for a carbon price to eliminate the use of fossil fuels, it need only raise the cost of using the fossil fuel to greater than its next cheapest competitor.  As there is no use of fossil fuel where the next cheapest competitor has an infinite price, the cost of the carbon price need never rise to infinity to eliminate the emission of CO2.  It is dubious that it needs to rise even to US$200 in the long term, although with current technologies it would need to rise higher to completely eliminate CO2 emissions.

  28. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Digby, we are arranging one, maybe two, interviews with Kevin Anderson over the next little while, so I will make sure to put that question on the list.

    If you or other readers have anything else you would like an answer to, ask it here and I will pass it along.

  29. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Kevin Anderson has an interesting article at his website about methods of inducing a decline in the burning of fossil fuel.  He contends that MBIs (market-based instruments) are inadequate to the task.  By MBIs is meant such methods as carbon taxes and cap-and-trade.

    (As an aside, I should mention that I've always wondered if instituting a carbon tax is like trying to divide by zero: for fossil-fuel use to tend to zero, the tax has to tend to infinity!)

    It would be interesting to follow up this Part Two article with Anderson's view of MBIs.  How about it, Andy?

  30. rustneversleeps at 07:42 AM on 29 November 2015
    The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    michael sweet,

    N2O has an atmospheric lifetime of about 120 years, and a global warming potential 300x that of CO2 over a 100 year timescale.

    Furthermore, the N2O emissions do not come from "gasses already in the atmosphere" unless you consider the Haber-Bosch process as doing that. The fact is that we have disrupted and dominate the nitrogen cycle far, far more than we have the carbon cycle.

    Methane, while it does have a shorter atmospheric life, also has a GWP of 34x that of CO2 at the hundred year timescale. Which is surely germane if we are talking about hittlng the 2C target.

    So I don't think your rejoinder to Tom really holds.

    (N2O is also a powerful ozone depleting substance, just to ruin our days a bit more...)

  31. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Leto @11.

    I am inclined to see the 'mugged old lady'analogy as not immediately applying to the full ΔTemperature resulting from AGW. There is obviously no bad stuff (no mugged old ladies) if AGW resulted in ΔT(full)=0.1ºC. So perhaps we should apply it to the ΔT(from now). Or better still apply it to emissions from now. But such meddling probably is too much of a strain on the analogy.

    Howver, I do rather like the idea of David Lewis @13 who likens present AGW policy to the 1939-40 Phoney War. A lot is being done (the UK was re-arming big-time well before Munich) but there is so far no sanction to properly begin doing what is inevitably needed to be done. In the greater public consciousness, the bad stuff has yet to be seen as that bad. Mind, comparing the available perspecive of Nazi malevolence in 1939-40 and the available perspecive of AGW today, playing a Phoney War with AGW is far less excusable.

  32. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?


    Can you post a link to support your claim that agricultural emmisions must be countered by sequestration to keep temperatures stable?

    It seems to me (without citations) that agricultural emissions will not need to be sequestered for two reasons:

    1) Methane and NO2 are shortlived in the atmosphere and after a decade or two decompose into CO2 and harmless gasses.  This is different from carbon dioxide which is essentially permanent once it is emitted.

    2) All agricultural emissions come from gasses already in the atmosphere. Therefore if agriculltural emissions are stable after a period of time the concentration of agricultural methane and NO2 will stabilize. (The resulting CO2 came from the atmosphere so it would not increase CO2).

    Lowering CO2 emissions from deforestation is necessary for long term stability of the atmosphere and may be difficult.  Some sequestration may be necessary but the scale required might not be as large as you suggest.

    This summary reviews many methods of reducing agricultural emissions by altering farm practices.  Greater farm efficiency and choice of crops that emit less greenhouse gases can help.  Managed forrest produces substantial income in many locations as long as enough food is produced.

    The required use of a technology as difficult as sequestration that has not yet been developed at any price is extremely risky.  

    I find it interesting that the IPCC declines to estimate sea level rise from the decline of the great ice sheets because it is not well understood while at the same time relies on unknown technology for sequestration.

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

    There are two relevant issues missing from this discussion. Firstly, the greenhouse gas emissions are already causing irreversible ocean acidification and warming, with a consequential deleterious impact on the operation of the marine ecosystem. Secondly there is the fallacious presumption that technological systems can be installed that will rapidly emulate what it has taken natural forces eons to do. Additionally, these techological systems naturally age despite the use of energy and materials for their operation and maintenance. Systems providing negative emissions may turn out to be worthwhile for a while but they cannot possibly offset the positive emissions. In addition, no realistic alternatives to the jet fuel used by the many thousands of aircraft, including airliners, or for the fuel oil used by the many thousands of ships, including cargo vessels, have been identifies despite research over many decades.

  34. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    The long term maintenance of a stable temperature requires zero net emissions.  Further, to bring emissions down sufficiently for a 2 C target requires western nations to reduce to zero net emission by 2050 or there abouts, even if we do not set national emission quotas on an equal per capita basis (the only truly fair way to tackle climate change).  That presents a major problem.  From 10-20% of total emissions are a direct product of agriculture.  That rises to about 30% if fossil fuel use in agriculture is included.  Of the direct emissions from agriculture, about 50% is in the form of nitrous oxide from fertilization of crops, and an approximately equal amount is from methane production either from rice production or from enteric fermation from cattle.  

    While studies have been undertaken as to how these values can be reduced, it would be foolish to think they can be eliminated.  Nor can we draw down from current levels of agricultural production without guarantteeing a global famine.  Ergo, for the forseeable future (ie, for several centuries down the track) we can expect NO2 and CH4 emissions from agriculture to equal at least 10% or current CO2eq emissions.  That is, absent carbon sequestration CO2 emissions cannot be reduced below approximately 10% of current values.

    Ergo, any viable future pathway must include carbon sequestration of at least 10% of current CO2eq emissions.  That is in addition to any carbon sequestration of continuing standing energy supply from fossil fuels, or from transport (some of which may be impossible to eliminate).

    The key point is that large scale sequestration is going to have to be deployed withing 30-40 years regardless of whether or not total emissions ever go negative or not.  That is, even the emmision reduction curves in the first figure above that "... assume no net-negative emissions technologies deployed ..." must in fact deploy large scale sequestration technologies to deal with agricultural emissions.  That being the case, we cannot consistently argue that we must follow one of those paths or fail to limit warming to a 2 C target.  If we can deploy sequestration technology that compensate for agricultural emissions, than we can deploy 50% more of that technology and generate substantial net negative emissions.

    This is not necessarily an optimistic point.  Such technologies may be unfeasible at large scales, in which case the view is very pessimistic indeed for in that case we will never reach carbon neutrality.  But more probably such technologies are achievable (though potentially with significant difficulty).  In that case the situation is not as cut and dry as Anderson suggests.  It is not, then, that we should not reduce emissions significantly faster than we actually are - but that it is not necessarilly cause for despair if we do not.  There probably will be a plan B, and must be if there is in fact a viable plan A.

  35. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Leto @9

    The truth is the solution is painful and always has been painful because it requires sacrifice for a future, that one can maybe foresee, but not see.

  36. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    When I read Schmidt's critique of Anderson (i.e. "I don’t think that that language is particularly useful, and I don’t think that concept is very helpful to making sensible decisions") I thought of the debate in the runup to WWII as described by historian Dan Todman, in this exerpt from a BBC History podcast produced in Sept 2009.  (I believe the podcast is here):

    "Todman: ...the government believes that the way to end this war is to depose Hitler. And it thinks that can be done without a complete commitment of British wealth, of British power, of British personnel. And the problem is that it is not a limited aim, getting rid of the head of a totalitarian dictatorship, its a total aim. The only way to do it is to smash that dictatorship. So they misjudge how the war is going to be fought. But they're not alone in doing that. I mean that's a widespread misconception amongst the whole population. And the limits on their freedom of action are not just conceptual. Its not that Chamberlain and members of his Cabinet want to continue with business as usual because they are somehow bad people, or that because they believe that always, business must come before national survival. Its really more that they are trapped in a situation, where they can't gain compliance on the part of the population, either on one side because of there's a great belief in voluntarism, both from the left and from the right, there's a strange situation in which you have both the Daily Express complaining about rationing, Beaverbrook launches a campaign against rationing in 1939, and the left also complaining about excessive compulsion.

    So really the Chamberlain government is trapped in a circumstance where it can't generate the national will that's necessary to fight a more total war, even as it gbecomes more and more convinced as it gets into the spring of 1940 that that is what it has to do. and really it is not until the circumstances change, until the fall of France, and this great threat to Britain that emotionally mobilizes the population, that ANY government can start to do that. And it has to be said that even when the Churchill government comes in in 1940 it takes a far more hesitant approach to the mobilization of domestic efforts than is often assumed. May to jUne 1940 is not as great and decisive a shift as we sometimes think in terms of things like rationing, and the conscription of women, those are events that take place much later in the war. And they're very concerned, the Churchill coalition, to stay behind the demand curve, really, they're operating inside the same set of limits as their predecessors, but they're doing so in a drastically changed international circumstance."

    Anderson, in this context, aims to speak the truth as he sees it, without regard to whether anyone is ready to hear it.  

  37. One Planet Only Forever at 03:58 AM on 28 November 2015
    Two-faced Exxon: the misinformation campaign against its own scientists

    Tom Curtis,

    I agree that generally is it inappropriate to refer to a person as being 'unacceptable'. However, I believe a person who has a history of deliberately pursuing unacceptable actions deserves the label. If they change their mind the label would no longer apply. As long as they persist in trying to get away with unacceptable actions 'they are unacceptable', or perhaps more correctly 'not deserving of acceptance'.

  38. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Leto @ 9:
    "We could have fixed things with minimal pain two decades ago; now it will take a bit more pain; wait any more and it will be worse."

    This statement is valid only if we are focused on the Earth's fever that is climate change, while ignoring the cancer that is our unsustainable economic growth. Such a fix would have continued economic growth using renewable energies, which would have continued with the planet's desertification and biodiversity loss with the rich developed world relatively oblivious of the collateral damage.

  39. Two-faced Exxon: the misinformation campaign against its own scientists

    Tom Curtis @#6

    Believe me, I don't want to  go "to easy on "Big Oil", not to mention "Big Coal" and "Big Natural Gas"."  But I also think there is dangers in people going too hard on them. There are plenty of articles over demonising them popping up every day now but I think these often tend to go over the top. I take your point that Big Oil may have been able to find freemarket lobby groups and think tanks that did not support denialism  and obfuscation - but that might have been hard, or impossible.

    Realistically, just about all freemarket organisations have varying degrees of right wing ideology "under the hood" and, at least in the US,  that has been strongly associated with denialism and anti climate science propaganda. I don't think there would have been a climate friendly substitute for the likes of ALEC etc to be found.

    I envisage that there may have been boardroom battles between the corporate psychopaths and those who care for their grand children and rather than blanket RICO like legal attacks against whole corporations, I would like to see subpoenas and FOI requests for the minutes of, and transcripts of those meetings so any guilty personalities could be outed.

  40. Two-faced Exxon: the misinformation campaign against its own scientists

    Bozzza @9 : [quote] "The markets obviously reward their endevours [sic] but the palms of industry must be greased and the more intervention into the market ideal means changing the core it's built around is going to get ever more complicated."

    ~ My apologies, Bozzza . . . but owing to my minuscule brain and/or lack of sufficient coffee, it seems your sentence [above] is not making much sense. Please trouble yourself to expand on the ideas you are wishing to present. We are already living in a highly complex as well as highly "complicated"  [  :-)  ] society . . . and we need to do a far better job of navigating somewhere safely between clumsy over-regulation and clumsy "market failure".

    And (as OnePlanetOnly is quick to point out) recent decades of general world-wide deterioration have resulted from an extensive amount of market failure. As he also points out: moral failure leads to market failure. A tendency of human nature, alas.

    [quote] "economies stand up by virtue of fossil fuels" [unquote] . . . is another such comment needing expansion. Perhaps you meant: "economies in the previous century stood up by virtue of fossil fuels" . . . for surely you were not intending to mean that the 21st Century world economy must necessarily and unavoidably "stand up by virtue of fossil fuels" into the foreseeable future ??

  41. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    MA Rodger @10, I take your point, and I was actually impressed with Schmidt in is interview. I did throw in the caveat that the statement was not so much wrong as one that did not stand up well in isolation. (And I didn't mean to cut bits away but rather intended to point to the bit that concerned me, knowing the more complete quotation was still there upthread.)

    My point is not really to criticise Schmidt. I  am sure Schmidt has an excellent understanding of what is required (better than mine, I am sure), but there is still something in the (perhaps unfairly isolated) statement that concerns me.

    Even in the case of mugged little old ladies we don't really, as a society, aim for zero muggings. Rather than putting every able-bodied adult on the street as a police officer to stop muggings, we accept a compromise, knowing that there are other demands on our resources.

    Rather than little old ladies, think of speed limits. Tackling global warmng by 'doing as much as possible' is like tacklng road safety by 'driving as carefully as possible' - rather than by setting explicit speed limits and blood alcohol limits. We shouldn't avoid setting a target for fear of making an arbitrary decision about an artificial threshold, because the alternative is to get lost in vague motherhood statements.

    Similarly, there is no simple image that comes to mind when you or Schmidt say 'do as much as possible'. Do you really expect me to do as much as physically possible to reduce my carbon footprint - give up all fossil fuels right now, today, stop heating the house, quit my job because it is beyond walking distance? You probably mean do as much as is reasonable, given the likely environmental, economic and societal costs of varying degrees of action... which demands some yardstick for reasonableness.

    If climate scientists and economists collectively told me it would cost 10% of my income to keep warming below 2 degrees (assuming others followed suit), I would happily pay that in a carbon tax or some sort of renewable subsidy. If you told me that 10% wouldn't cut it, and we were heading for 4 degrees warming at that sort of cost, I would be keen to pay more, and do more, and I might look at restructuring my job and my life to avoid driving. It's not realistic to ask me to do everything possible, and even if I literally do everything possible, the world as a whole will never 'do everything possible' - it will do the minimum it thinks it can get away with, which is why I think we do need targets. Otherwise, there is a risk of sliding into some sort of vague, luke-warmist approach, which is effectively what the world is doing now.

    Given how much time has been wasted debating the faux pause (not the fault of anyone here, of course), I really don't think this issue is 'mostly a waste of time'.

  42. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Leto @9.

    I think that is a little unfair on Schmidt. He was actually answering the question of whether a 2ºC target was still relevant. His point involved the analogy of "the number of little old ladies you want to have mugged every year" which is obviously zero. But you wouldn't be discussing it if it was zero or if zero was possible. He says of a target for temperature, it should be as low as possible and of the 2ºC target "Two degrees is not totally out of the question, though I think it is not likely that we will make it." It is only in this context that your quote applies and it did come with an important finale answering the question being asked, a finale quoted @6 but that you cut away. Schmidt is saying we need to do as much as possible so it is the same decisions and same actions for 3ºC as it is for 2ºC or 1.5ºC. Thus the conclusion "So discussion of the target – quite frankly – I think is mostly a waste of time."

  43. So what's really happening in Antarctica?

    Glaciologist Jan Wuite also put up an explainer about how this new article by Zwally et al fits in the wider context of Antarctic studies.Complements this one by Bamber nicely.

  44. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    "But any of the decisions that we’re making now, to get us on a path towards reducing emissions, they’re the same decisions we’d be making if the target was 3C, or 2C, or 1.5C. The actual actions that people need to make are the same." [Schmidt]

    As much as I respect Schmidt as a scentist, I think this is not quite correct, or at least it is a statement that does not stand well in isolation. The type of actions required are the same, and the general directions in which we have to head are the same, but the urgency required for different targets is not at all the same.

    This article is a timely reminder that the situation has already become urgent, and it is not enough just to vaguely embrace 'actions that people need to make', such as a slow move to renewables. The actions we needed to take in the 80s and 90s and 00s are not the same as the actions we need to take now, and the more we delay the more drastic the economic upheaval that will be necessary. We could have fixed things with minimal pain two decades ago; now it will take a bit more pain; wait any more and it will be worse.

    Gavin Schmidt is probably right that there is no sudden risk-transition point in the region of 2 degrees, but people need to have the costs of each trajectory spelled out, both envirnomental and economic.

    Frankly, as an Australian who lives on a dry continent prone to bushfires, I find the current ~1 degree of warming is already unacceptable for a number of reasons. The news is full of climate-related woe, not all of it obvious. There is even an argument to be made that droughts in Syria have contributed to the civil war there, and hence to the spread of terrorism. Dangerous climate change is not in the future; it is now. The idea of >2 degrees warming is simply awful.

    My biggest concern about 2 degrees as a target is that it is already too much, especially after allowing for uncertainty in predictions and inertia in our economic and political institutions. But the fight for more aggressive targets should at least begin with the fight to defend the 2 degree target.

  45. Two-faced Exxon: the misinformation campaign against its own scientists

    It's about who's in charge. Fossil fuel providers give the economy a baseline of dependability. They are an institution in more than a few ways.

    The markets obviously reward their endevours but the palms of industry must be greased and the more intervention into the market ideal means changing the core it's built around is going to get ever more complicated.

    Why would an institution argue for its own demise? Governments invited the fossil fuel providers to provide goods and services to the people and apart from being a tax base they also enjoy the baseline of activity- and therefore lack of anarchy- they provide.

    Governments are hamstrung: they can't just let billions of people fall into unemployment; economies stand up by virtue of fossil fuels; and they stand up by being fed incentives.

  46. The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    Gavin Schmidt, in
    The Carbon Brief interview of Oct 15 2015, discussed those who talk of targets that simply should not be exceeded such as 2C or a set amount of CO2 emission allowed by naming Kevin Anderson in particular.  He said:   "I don’t think that that language is particularly useful, and I don’t think that concept is very helpful to making sensible decisions". 

    According to Schmidt, "Two degrees is not totally out of the question, though I think it is not likely that we will make it. But any of the decisions that we’re making now, to get us on a path towards reducing emissions, they’re the same decisions we’d be making if the target was 3C, or 2C, or 1.5C. The actual actions that people need to make are the same. So discussion of the target – quite frankly – I think is mostly a waste of time."

    Anderson believes there is a some amount of warming civilization could get away with, but if there is some greater amount, civilization as we know it would end.  And, he says, if people thought 2C looked like it was the borderline between these two conditions, as science has advanced, it has dawned on many that 2C is too much. 

    It would be of interest to know if types like Schmidt would argue the opposite, i.e. that increasing scientific knowledge indicates that it will be safe to exceed 2C.  Will 3C, or 4C or 6C be just more of the same but hotter?   No runaway feedbacks in sight?  No dramatically escalating costs of coping?  Civilization keeps humming along?  How confident can anyone be? 

    I think many don't speak as clearly as Anderson because they believe that human beings need to be conned at this point or they will despair and do nothing. 

  47. Two-faced Exxon: the misinformation campaign against its own scientists

    Tom: I didn't mean to imply the Exxon's claims about supporting a carbon tax are genuine - they are not. But claiming to support a "revenue neutral" carbon tax is pretty common among corporations and moderate Republicans. Of course, what they mean by this is that not only does all of the carbon tax revenue get diverted to tax cuts, but in order to garner corporate support, it would have to be focused on tax breaks they prefer, such as corporate rate reductions, lower capital gains, etc.

    A carbon tax is actually a fee, not a tax, as it is something that is charged based on use of a public service or public property. Fees are typically NOT put into the general pool, let alone used for tax cuts. They are used to fund the maintenance and provision of the service or property that generated the fee, or closely related items. Gas "taxes", national park entrance fees, automobile registration fees and patent application fees are all examples of how this works. In principle, all of the carbon tax should be used for mitigation and adaption. There is no reason to connect them to tax cuts at all other than as a concession to the GOP. In that case, however, this should not be your starting position in the negotiation. If you start by backpeddling from your own 20, the other team is going to have a touchdown before you know it.

    What would be just in this case? The punishment of gross polluters and not only a forward-going carbon fee but a retroactive one that forced polluters to compensate for their past activity, with interest and penalty. Start with something strong, and you can end with something more reasonable, like splitting the carbon tax three ways between tax cuts, deficit reduction, and spending on adaption/mitigation, with the tax cuts being a per-capita dividend rather than rate cuts which would effectively give the overwhelming majority of the cuts to a very small number of people, even though they money supporting such cuts was generated by property we all own equally.

    Exxon, I suppose, would go along with a carbon tax in return for a big fat corporate rate cut. But it doesn't deserve one, and we certainly shouldn't be offering one unless we get concessions in return.

  48. One Planet Only Forever at 13:44 PM on 27 November 2015
    The Road to Two Degrees, Part Two: Are the experts being candid about our chances?

    It is so tragic to have to have effort put into sussing out and presenting the fundamental cause of the tragedy faced today and in the future that had been so clearly stated in the 1987 UN Report "Our Common Future".

    The following pair of statements are presented early in that document.

    "25. Many present efforts to guard and maintain human progress, to meet human needs, and to realize human ambitions are simply unsustainable - in both the rich and poor nations. They draw too heavily, too quickly, on already overdrawn environmental resource accounts to be affordable far into the future without bankrupting those accounts. They may show profit on the balance sheets of our generation, but our children will inherit the losses. We borrow environmental capital from future generations with no intention or prospect of repaying. They may damn us for our spendthrift ways, but they can never collect on our debt to them. We act as we do because we can get away with it: future generations do not vote; they have no political or financial power; they cannot challenge our decisions.
    26. But the results of the present profligacy are rapidly closing the options for future generations. Most of today's decision makers will be dead before the planet feels; the heavier effects of acid precipitation, global warming, ozone depletion, or widespread desertification and species loss. Most of the young voters of today will still be alive. In the Commission's hearings it was the young, those who have the most to lose, who were the harshest critics of the planet's present management."

    That was based on what had been happening prior to writing the report. A much blunter statement would be made today, and no leader (political or in business) should be able to claim they were not aware of this.

    The obvious threat to humanity is the shamelessness of the group of callous powerful wealthy people (undeserving of their wealth or power) pushing for what they want (and what they uderstand is unaccpetable) through fronts like the Tea Party and the House Freedom Caucus (powered by the science of misleading marketing).

    That small group of undeservingly wealthy people understand that their wealth and power is not deserved. And they cannot be expected to care how much damage they cause trying to maintain and expand it.

    They have abused their power in many ways including getting laws established that alow them to have the financial ability to ruin the political future of candidates in just enough regions to maintain their stanglehold on the most powerful nation on the planet (and fair to say also undeserving of its wealth and power) through a few elected representatives (willing to follow orders unflinchingly without consideration of the actual future consequences of their actions - or scarier is the potential that they believe that if they do not follow the orders eternal darkness will decend on the planet).

    The belief that the developed economies are deserving of being maintained (let alone be expanded) is a grand fairy tale that the populations benefiting within them will struggle to free their minds from. And as long as those who do not care about the future can get away with their desired freedom of pursuits (by gathering support from easily impressed people through misleading marketing appeals to greed and intolerance) humanity's future is indeed bleak.

  49. Two-faced Exxon: the misinformation campaign against its own scientists

    OPOF @5:

    "'Exxon' did nothing. Some 'powerful people able to influence Exxon leadership or within Exxon' did many unacceptable things hoping to be disguised within Exxon or otherwise be difficult to 'identify as responsible for the unacceptable actions'."

    There is no such thing as an "unacceptable person".  Only unacceptable actions.  In other respects I entirely agree with your excellent comment.

  50. Two-faced Exxon: the misinformation campaign against its own scientists

    Nick Palmer @4:

    "While acknowledging that those organisations and politicians that Exxon-Mobil sponsored/still sponsors did, and continue to, spread a lot of mis/disinformation about climate science, that's not all those organisations do. They lobby against taxes, increased regulation and for reduced government interference in corporate affairs. All things that business likes. I think it fair to say that Big Oil may have funded them even if there had never been such a thing as climate science denialism just to get, in their view, the best and easiest ride for their corporation and shareholders."

    I think that goes to easy on "Big Oil", not to mention "Big Coal" and "Big Natural Gas".  The reason is that there are sufficiently many think tanks, and they are easy enough to establish, that fossil fuel corporations could easily have funded think tanks that pursued those other ends, while being realists with regard to global warming.  There choice not to do so, therefore, is a choice to fund global warming denialism.  They may not have had a similar choice with regard to the US Chamber of Commerce and other round table lobby groups, but could clearly have articulated a distinct position when the US Chamber of Commerce made remarks depreciating the science of climate change.  They could also have lobbied strenuously internally to such organizations for a realistic (not pragmatic) approach.  Again failure to do so indicates that when such round table lobby groups of which their Corporations were members made statements supporting denialism specifically, of FUD more generally, they spoke for the fossil fuel corporations (ie, the primary beneficiaries of such FUD).

    Note that since 2009 (or 2007?), Exxon gets a pass on the second point - they did clearly articulate a realistic view on climate change regardless of the articulated views of any round table lobby groups of which they were members, but they continued to fund think tanks and politicians who articulated denier viewpoints on climate change when otherwise 'business friendly" alternatives existed.

    The strategy appears to be one of delaying action while taking sufficient action to create plausible deniability that that was their strategy, thereby affording them legal protection.

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