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Comments 43351 to 43400:

  1. Update on BC’s Effective and Popular Carbon Tax

    This article makes no mention of the increase in British Columbians driving just across the border in Washington to fill their gas tanks. (http://bc.ctvnews.ca/tax-gap-has-b-c-ers-driving-south-for-gas-watchdog-1.1285011)

    According to Statistics Canada, the number of same-day return trips by BC drivers across the US border has increased by more than 100% since the carbon tax was implemented, from 421,665 per month in June 2008 (the last month before the carbon tax), to 868,915 as of May 2013.

    Source: Statistics Canada. Table427-0005 - Number of international travellers entering or returning to Canada, by province of entry, seasonally adjusted, monthly (persons), CANSIM (database). (accessed: 2013-07-25)

    Yes, carbon taxes will change people's behaviour... thought perhaps not as intended.

  2. michael sweet at 22:14 PM on 25 July 2013
    2013 SkS Weekly News Roundup #29B

    JvD,

    When you use strong words like "deliberate lies" you are much less convincing.  It makes you look especially bad when you accuse others of deliberate lies and then it is pointed out that your statements are contradicted by the Saudi gevernment.  Who is the deliberate liar here?  It appears to me that you are the deliberate liar, and not the environmentalists.  If you want to convince others to listen to your position you need to change your tune.  You may have a point, but I will not read your posts as long as you make wild accusations about others that can easily be pointed back at you.

  3. 2013 SkS Weekly News Roundup #29B

    JvD,

    What they (deliberately!) neglect is that the conventional retail electricity price contains not only the cost of generation (which is about €5 ct/kWh), but also the cost of transmission and distribution.

    How is that a problem? One minute you're saying that "the cost of production" should be the only measure, the next you're saying that it's unfair to compare the "cost of getting electricity into my house" between two technologies because one manages to bypass the cost of transmission and distribution by virtue of the fact that it's already at my house!

    The fact that rooftop PV doesn't have transmission and distribution costs is an actual benefit that means it gets to compete with end-user retail prices rather than wholesale electricity prices.

    Anyway, back to your cost of production bugbear:

    Yes I am. The only sensible way to determine the competitiveness of different energy options is to compare the cost of production of those sources. If the Saudi's were to raise the domestic price of oil to the international level, that would tilt the playing field domestically to other sources, but it would not change the basic fact that oil is far more cost effective than those other sources.

    The cost of production is irrelevant. Yes, Saudi Arabia has the world's lowest oil production costs, but taking advantage of that to sell oil cheaply domestically instead of selling that same oil at the going market rate is not only a real cost, it enourages inefficient resource allocation!

    Scenario A: Saudi Arabia produces a barrel of oil for $6, and sells it domestically for $6. Citizens benefit from cheap oil, with those more able to consume oil benefitting the most. (Note that I'm actually taking your word for it that they really are selling it at "production cost", since I haven't actually seen any evidence of the "true production cost" vs domestic retail price, and I have doubts that the "true production cost" is even publicly known; it would also depend heavily on how it is accounted.)

    Scenario B: Saudi Arabia produces a barrel of oil for $6, and sells it at the going market rate of $100. The extra $94 is used to give tax breaks, education, health services, welfare, etc. Citizens pay more for their oil, but avoid paying $94 through tax or reduced services that they would have had to pay somehow otherwise. The benefits of that $94 can be targetted to achieve desired outcomes. The higher cost of oil encourages more efficient use (e.g. not burning it for electricity!) and encourages the use of alternatives that will allow the oil reserve to last longer and ultimately derive more revenue.

    As has been pointed out to you repeatedly, the Saudi government calls it a subsidy; I do not think it is appropriate to accuse others of deliberate lies to misinform the public just because they don't adhere to your personal definition of the word. You're also picking the country in the world with the cheapest production cost and the best chance of retailing their oil above that production cost to dispute all subsidies.

    To me, an apples-to-apples comparison is between true market values of each commodity before any taxes or subsidies have been added. This means, for example, that when comparing wind to fossil fuels, then any tax breaks or special benefits that wind receives should be removed and any excise taxes on fossil fuels should be removed and then the two compared so that the true cost can be ascertained. But how does it help to compare the retail price of wind power in my country with the retail price of domestically-sold oil in Saudi Arabia? Can I buy that oil at that price? No? Then it's irrelevant. If the Saudi's want to forgo the extra revenue that they would get if they sold all their oil at market rates then that's their problem; it makes no difference to me.

    Likewise, if I put solar PV on my roof, I don't care that the electricity generator is generating power at half the price — I can't buy it for that price! It needs to get to my house, which makes it twice as expensive. What it costs me is what counts.

    And, of course, once we start adding in externalities to get the true costs of burning those fossil fuels, the point becomes moot anyway...

  4. 2013 SkS Weekly News Roundup #29B

    As another egregious example of camparing apples to oranges as a result of wrongly accounting for energy taxes and subsidies, consider the level of discussion in my country - the Netherlands - concerning the so-called 'grid-parity' of rooftop solar versus conventional generation. All of the so-called 'green' groups in my country are lobbying hard for promotion of rooftop solar. They are doing this by claiming that rooftop solar is "already cheeper than conventional electricity". They are claiming that since rooftop solar costs about €20 ct/kWh, and retail electricity prices are a few €ct/kWh greater than this, that rooftop solar is 'competitive without subsidies'.

    What they ( -snip-) neglect is that the conventional retail electricity price contains not only the cost of generation (which is about €5 ct/kWh), but also the cost of transmission and distribution. Moreover, it contains the high taxes on electricity that are applied in my country. So when these taxes and costs are included, it is obvious that rooftop solar is 400% as expensive as conventional electricity. Yet these 'green' groups are claiming continuously that if my countrymen would switch wholesale to rooftop solar that this would result in significant financial savings for the country! (-snip-)! Since we use about 100 TWh of electricity per year in my country, if we would switch to rooftop solar it would cost at least €15 billion per year extra, even ignoring the very high cost of additional transmission, backup and storage needed to run completely on intermittent renewables such as solar power.

    The green groups are ignoring this. Shockingly, they are even turning around and saying that the retail price of €20 ct/kWh is going completely to the 'big bad'energy companies. Now, I know that these green groups realise that of this €20 ct/kWh only about €5 ct actually goes to the energy companies, and that the rest is taxes and gridcosts. (-snip-).

    Moderator Response:

    [DB] Inflammatory snipped.

  5. 2013 SkS Weekly News Roundup #29B

    You seem to be insisting a special definition of subsidy. Lets not get hung up on definition. How about the claim then that goverments are providing $600B of various kinds of price support that, if removed, would increase consumer cost of fossil fuel, making other sources more competitive. Are you contesting this statement?

    Yes I am. The only sensible way to determine the competitiveness of different energy options is to compare the cost of production of those sources. If the Saudi's were to raise the domestic price of oil to the international level, that would tilt the playing field domestically to other sources, but it would not change the basic fact that oil is far more cost effective than those other sources.

    Certainly, it would change nothing in the cost effectiveness of oil versus alternatives in countries outside Saudi Arabia. In anything, reducing oil demand in Saudi Arabia by raising domestic prices by 600% (which is what it would take to achieve international prices level domstically) could increase the amount of oil available to the international market, which could reduce the international price of oil, thereby reducing the competitiveness of alternatives globally. Even if the international price of oil would not change, then there is no reason to assume renewables would really take off in Saudi (although efficiency of oil use would likely improve). If the domestic price of crude were to be raised, then international coal would be the next-best economic choice for Saudi, increasing the co2 emissions of the country rather than reduce them. We now know of course that Saudi is investing heavily in nuclear energy, which alleviates the risk of Saudi turning to coal. Solar energy might seem a no-brainer in sunny Saudi, but it turns out that desert environments are not especially favourable for solar, due to the increased burden of dust and high operating temperatures.

    In order to maintain clarity in comparing the economics of different energy sources, I believe it is necessary to judge them based on cost of production only, including all indirect costs, but excluding as much as possible any subsidies and taxes. (-snip-).

    (-snip-). In my own experience, I chastised my local chapter of Greenpeace (of which I am still a donating member) from bringing this very same lie several years, and they have backed-off from it (grudgingly, though not completely). (-snip-).

    Moderator Response:

    [DB] Inflammatory snipped.

  6. The Economist Screws Up on the Draft IPCC AR5 Report and Climate Sensitivity

    ianW01 & jdixon1980,

    1)  I modified the graph in question so that all three red circles align with 2100, and added a trend line from the end of the observational data to 2100 for each.  Here is the result:

    You may think there is a gain in visual clarity, but I do not.

    2)  The original graph does not cause any confusion if you do not assume graphs can be interpreted independently of their accompanying text.  In the case, the accompanying text, ie, the legend, clearly states:

    "Measured and Projected temperature to 2100"

    That legend precludes interpretations in which the red dots are considered to indicate temperatures other than at 2100.

    3)  In that regard, ianWO1's interpretation of the graph (@16) as showing the time to equilibrium temperature is entirely unwarranted.  In fact, in scenario RCP 6.0, forcings do not peak until about 2150 and temperatures are still rising at 2300.  Beyond 2300, whether or not temperatures will reach, exceed or fall short of the equilibrium for the Charney Climate Sensitivity depends on a number of factors outside the scope of the scenario.  Further, depending on those factors temperatures may be unstable for millenia, although rates of change are unlikely to match those in the twentieth century, much less the twenty-first.

    4) I also like jdixon1980's suggestion for an animated gif and think it would be a superior presentation.  On the other hand, I am not prepared to prepare it myself, and therefore am disqualified from criticizing other people who have voluntarilly surrendered their own time to prepare the original graph for not spending more of their own time to make the superior product.  Perhaps jdixon would volunteer? 

  7. grindupBaker at 16:31 PM on 25 July 2013
    Why doesn’t the temperature rise at the same rate that CO2 increases?

    @Me#16 Correction because delta-radiation ~proportional to delta-t for these <.01 dt ratios even though proportional to t**4. Seems to me that 75% +ve feedback is what's been added average (presumably increasing). +0.8C thus far balances 3.75 wm**-2 * 0.8 / 1.2  = 2.50 wm**-2. OHC gradient looks like 0.85 wm**-2. CO2 forcing 5.35*ln(10/7) = 1.91 wm**-2. So, (2.50 + 0.85) / 1.91 = 1.75 (75% +ve feedback). Right ?

  8. grindupBaker at 15:48 PM on 25 July 2013
    Why doesn’t the temperature rise at the same rate that CO2 increases?

    To the extent that basic CO2 forcing formula is accurate and the reanalysis OHC is accurate and Dr. Randall was accurate saying 3.75 wm**-2 is balanced by +1.2C then it seems to me that 42% +ve feedback is what's been added average (presumably increasing). +0.8C thus far balances 3.75 wm**-2 * 0.5 = 1.87 wm**-2 (0.5 per t**4 at ~287-289 degrees K). OHC gradient looks like 0.85 wm**-2 (Dr. T says it's 0.9 wm**-2). CO2 forcing 5.35*ln(10/7) = 1.91 wm**-2. So, (1.87 + 0.85) / 1.91 = 1.42. What am I misunderstanding ?

  9. grindupBaker at 15:26 PM on 25 July 2013
    Why doesn’t the temperature rise at the same rate that CO2 increases?

    @DAK4Blizzard #3: Extra info. Dr. Kevin Trenberth says in SFU lecture video posted as "The Role of the Oceans in Climate" oceans mix well to 20m depth in summer, 100m in winter - can take 90m as average and will delay response by 6 years. KT says 3.5m depth = all atmosphere heat. Dr. Randall says top 6.5m land is what's considered (insulates well) and equivalent to 3.25m ocean depth but I recall a lady climate scientist saying only ~2m ocean depth = all land heat (my memory vague on that latter).

  10. The Economist Screws Up on the Draft IPCC AR5 Report and Climate Sensitivity

    Richard Lawson @19, I would be interested in how you found that "slew" of papers.  A search of google scholar for "climate", "sensitivity" post 2008 returned 282,000 hits.  I doubt you have read even 10% of them so as to be able to determine that they are dominated by low sensitivity results.  I suspect that you may have read about the "slew" of papers on some denier site where (if they are like Patrick Michaels or WUWT), they only report the few papers returning a low climate sensitivity and not those many others reporting a high climate sensitivity.  Thus they will not have reported on Haywood et al, (2013) which reports climate sensitivities from 2.7 to 4.1 C per doubling of CO2 from a comparison of the output of eight models with pliocene conditions (table 2).  Nor on Eagle et al (2013), which report a high regional climate sensitivity in central China.  Nor on Li et al (2013), which report a climate sensitivity of 5.4 C per doubling of CO2.  Nor (finally) on Previdi et al (2011), who report that the Earth System Sensitivity, ie, the climate response allowing for slow feedback such a the retreat of ice sheets etc, may well have an impact in periods short enough to be relevant to policy.

    However, it is not true that all recent low climate sensitivity estimates have been based on simple energy budget models, nor that their use are the cause of the low estimate.  Schmittner et al, for example, use the Uvic earth system model, but reach their low sensitivity estimate because of the (probably unrealisticly) low estimate of the difference in temperature between the LGM and the present.  Nic Lewis's recent two recent efforts (only one of which was peer reviewed) have low sensitivities at least in part because they do not allow for the effects of recent La Nina's (which will cause the estimated climate sensitivity to be low). 

  11. Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature

    OneHappy, the most thorough and extensive attempt to review Cook et al, 2013 for potential errors was done by Cook et al 2013.  This was done by contacting authors of papers and asking them to independantly rate their own papers.  Curiously, the resource this independent vetting of the result provides has been ignored by "skeptical" critics of the paper.  That is because if you simply ignore the abstract ratings, Cook et al could have reported that 96.57% of climate science related papers that state a position are rated as endorsing AGW by their authors.  And that is the result they do not want to accept.

    With suitable caveates, the author self ratings can be used as a check on the error rates in the abstract ratings.  If we do so by simply treating them as basic error rates, after correcting for errors we will simply reproduce the statistics for the self ratings (which is not interesting).  We can compare ratio of particular types of errors in particular categories and find some interesting facts.   Doing so, we find that among papers rated by both authors and by abstract, 1.98% of papers rated as endorsing the consensus by the abstract raters were rated as rejecting the consensus by the authors.  In contrast 30% of papers rated as rejecting the consensus by abstract raters were rated as endorsing the consensus by the authors.  If we correct the headline result on that basis, it reduces the 97% endorsing the consensus to about 95%.

    As an alternative, we can assume that any paper rated as rejecting the consensus by either author or abstract rater actually rejects the consensus; and that any paper not rated as rejecting the consensus by either, but rated as neutral by either is actually neutral.  If we do this, we still find that 90.6% of papers that state a position endorse the consensus.

    It should be obvious that the assumptions in the last example are ridiculous, and that consequently the result is lower than any concievable result from a reasonable analysis of the data.  Yet still the result shows >90% of papers endorsing the consensus.  I believe this supports the position I have stated previously (before I had access to the detailed data on author ratings) that the level of endorsement is almost certainly greater than 90%, and is most likely greater than 95%.

  12. grindupBaker at 13:29 PM on 25 July 2013
    The climate change policy discussion I wish Andrew Neil would have on BBC

    Andrew Neil blogs "The recent standstill in global temperatures is a puzzle. Experts do not know why it is occurring...". Most likely he's never heard about oceans or been to the seaside. Oceans are a double-edged sword. ~5,900 Zj for just 1 degree average rise is a huge buffer with ~8 Zj p.a. being added the last decade or so but once the heat is in the oceans it'll be tricky getting it out. ~10,000 Zj energy needed to melt all land ice off Antartica and Greenland. But the earlier potential effects such as frozen methyl hydrates release seems somewhat pressing. I haven't seen a climate science estimate of reasonably safe additional ocean heat.

  13. Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature

    OneHappy,

    I suggest reading through earlier comments, there was some discussion on the exact ratings applied to some papers and suggestions on how Cook et al might be meaningfully "audited". In particuar, any bias in how the papers are chosen (e.g. simply checking the papers of known sceptics) will invalidate attempts to extrapolate the error rate to the sample as a whole — if you don't want to recheck every rating then you need to choose a random sample of papers and see what error rate you get with those, taking into account both the papers that you didn't disagree with and those that you did. And don't forget the self-ratings of the authors!

    The bottom line, however, is that nobody has come up with a huge hoard of papers that did not endorse the consensus yet somehow escaped that categorisation in Cook et al. You can always find errors in any human endeavour (and the paper itself specifically quantified disagreements between Cook et al raters, though remember that a disagreement in rating doesn't automatically translate into a disagreement in endorsement/non-endorsement) but the real question is, what impact does that error rate have on the result?

    Given the overwhelming numbers involved, even gross errors would not sway the results very much. For example, as Tom Curtis pointed out previously regarding the author self-ratings, in order for the original authors' level of endorsement to drop to 94.5% — a figure I would still consider overwhelming — you would need to believe that half of the original authors mistakenly assessed their own papers as endorsing the consensus when they should have been rated as neutral.

    Now, it's true that some (e.g. Richard Tol) managed to mis-rate their own papers (thereby incorrectly claiming Cook et al were wrong) but half? And that would still make the headline look much the same. Why? Because there really are bugger-all papers in the literature that actually dispute the consensus. What's even worse is that when you examine those papers, certain opinions about quality and rigour invariably form. In other words, not only are there very few papers disputing the consensus out there, but most of those are also rubbish with obvious errors that make you wonder how they got published in the first place. (Actually, not really — it's painfully obvious how they got published in most cases; it's just sad.)

    There's no need to have doubts, the assessments are all online. Check for yourself!

  14. Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature

    On reflection I think if there are 4 mistakes in over 4,000 abstracts rated then 0.1% is an acceptable rate of error, but still interested in other opinions on this.

  15. The Economist Screws Up on the Draft IPCC AR5 Report and Climate Sensitivity

    Richard@19,

    You're correct.

    For example, simple Energy Budget models ignore the albedo change from sea ice/ice sheet melt, also the permafrost melt and methane clathrate release is ignored. That's because the machanics or the extents of those feedbacks are unknown. However, with more data about recent sea ice melt, I expect the sensitivity figures will be updated upwards in the near future.

  16. BC’s revenue-neutral carbon tax experiment, four years on: It’s working

    usbuyer:

    There's certainly some truth to what you say, whenever I drive across the border (about twice a year) I always fill-up. But I always have done that, even when I used to live in Alberta. And there has been in an increase in Canadians making cross-border shopping trips in the past few years, not only in BC, but in the other provinces also. It's unclear how much of this increase has been driven by the ~8cents per litre carbon tax, which might save an additional $5 per fill up. As you know, a lot of other goods are cheaper in the US.

    I am working on crunching some numbers on this and will post a link here when I have finished. On a preliminary basis, I think that this might account for about an apparent 2% reduction in  BC's per-capita fuel consumption. The latest figures, in a peer-reviewed study, show that BC fuel consumption has fallen by about19% relative to the rest of Canada since the carbon tax was introduced. So, perhaps 10% of the reduction might be attributable to cross-border shopping rather than other behaviour changes spurred by carbon taxes. But I need to check the calculations first.

  17. BC’s revenue-neutral carbon tax experiment, four years on: It’s working

    Don't have an opinion on whether BC carbon tax is good or not. Do know that I used to spend about $2500 year buying gas in BC - now go across the border - fill up (and play a round of golf) - spent less than $200 on gas in BC last year. Many of my neighbors go to US on the weekend - shop - and gas up. Of 6 families around my place, I would estimate that gas buys in BC were around $15000 year, now not more than $1000 year. Don't know of any neighbors driving less - just going south for gas to save money. Need to look at all the impacts (lost sales, etc) when contemplating higher taxes.

  18. Levitus et al. Find Global Warming Continues to Heat the Oceans

    MA Rodger - Oh my, I missed that throwaway line the first time through. Eschenbach (somehow) dismisses CO2 in a sentence completely unrelated to anything else in the blog post, with no supporting evidence whatsoever. 

    So: a discussion that adds nothing to Levitus 2013, with unsupported aspertions on OHC data accuracy and a complete non sequitur regarding CO2 tacked on the end. I believe that sums up that Eschenbach post - in my opinion it's not worth the time to read. 

  19. Levitus et al. Find Global Warming Continues to Heat the Oceans

    dvaytw @36.

    Is there anything specific that bothers you. My main take-away from that Wattsupian post is that the author is a total idiot. 45+100+60. That's a lot smaller than 205. An' it ain't CO2 wot dun it, neever!! Then such arrant stupidity is quite a common on that planet.

  20. Levitus et al. Find Global Warming Continues to Heat the Oceans

    dvaytw - Aside from the (unsupported) aspersions on OHC data at the end, that post really doesn't say anything new. The oceans have a vertical temperature profile, they have accumulated huge amounts of energy over the last half-century of measurements, that translates into different amounts of warming over the vertical ocean profile. 

    While the temperature changes he plots are interesting, the raw temperature data is already available on the very same site he got the OHC information from - and by reversing to degrees C he's thrown away (cancelled out) the volume and total energy values of interest. 

    Overall, that post contains nothing much of interest. Far more informative to read the original Levitus 2012

  21. Levitus et al. Find Global Warming Continues to Heat the Oceans

    Wattsup has a blog post about this wherein he claims:

    "The nice thing about the ocean is that the temperature and heat content are mathematically related by the fact that it takes about 4 megajoules to warm a tonne of water by 1°C. This lets us convert from heat content to temperature and back as needed.

    Remember that the three layers have very different volumes. So a terajoule of energy added to the shallow 0-100 metre layer will warm it more than the same terajoule of energy added to the more voluminous 700-2000 metre layer. Fortunately, NOAA also provided the ocean depths on a 1° x 1° grid, so we can calculate the volume of each of the layers. Once we know the volumes, we can calculate the temperature changes. Figure 4 shows the same data as in Figure 3, except expressed as a temperature change rather than as a change in heat content."

    http://wattsupwiththat.com/2013/05/10/the-layers-of-meaning-in-levitus/

    Comments on that?  

     

  22. The climate change policy discussion I wish Andrew Neil would have on BBC

    An important point not highlighted by Dana, but critical in the policy arena, is the trajectory towards the necessary approx. 80% reduction of emissions (more if related to today's emissions) by 2050. The longer humanity dithers, the steeper the reductions will need to be, the stronger the adverse impacts on "traditional" economics. This was recently reiterated (aka it is old news) by Kevin Anderson here. It can be comprehended even by non-economists. Those who accept the science while defending current economic practises should probably be the strongest supporters of early and sweeping decarbonization efforts. And indeed, it looks to me that some, like the Germans, are trying hard. Maybe not hard enough considering the challenge, but harder than most ...

  23. Richard Lawson at 23:11 PM on 24 July 2013
    The Economist Screws Up on the Draft IPCC AR5 Report and Climate Sensitivity

    Many thanks Tom Curtis @15. OK I have another question. I have been puzzled about the recent slew of papers giving low climate sensitivity. Then I read that the low CS papers are based on simple Energy Budget models, and that the more complex general circulation models which deal with more factors will deliver higher CS values. 

    Is that correct?

  24. Glenn Tamblyn at 19:11 PM on 24 July 2013
    Why doesn’t the temperature rise at the same rate that CO2 increases?

    David Sanger

    I am no expert on this but the general sense I have is something like this:

    A major part of the ocean circulation patterns in the upper half of the ocean is currents generated by the winds, particularly the major permanent wind patterns, the Easterly Trade Winds near the tropics, and the Westerly Roaring Forties. These winds generate large circular currents, the Gyres, one per ocean basin with smaller child gyres as well. These rotate clockwise in the Northern Hemisphere and counter-clockwise in the south.

    This circular movement pushes water towards the center of the gyres which then creates a downwards water flow in the central region as this is the only place the inflow of water can get out. This is described in more detail in the theory of Ekman Pumping.

    Additional factors come into play in the Southern Ocean with the interaction between the gyres and the circumpolar current that circles the Antarctic. Also the fact that the cold surface temperatures in the Southern Ocean mean that the temperature gradient between the surface and the deeper waters is less so Ekman pumping can more easily move water down since the buoyancy gradient is lower.

    In recent years the speed of the Westerlies has increased. The speed of the Trade Winds may also have increased. And the latitiudes where the westerlies are blowing are shifting polewards as the Hadley Cells expand.

    In principle, increases in the wind speeds should 'spin up' the gyres, increasing the Ekman transport, thus more water being moved from the surface to the mid depths - 1000 to 2000 meters - and thus able to carry more heat with it. But the details are apparently rather complex due to the interactions in the Southern Ocean. This is why the Southern Ocean is a region of intense research right now.

    Things like the PDO and perhaps even the ENSO cycle may well be smaller scale consequences of a broader mechanism involving fluctuations in the winds and Ekman transport. With more research this area has the potential to really nail a lot of our uncertainties wrt natural climate variability.

  25. Timothy Chase at 18:23 PM on 24 July 2013
    Why doesn’t the temperature rise at the same rate that CO2 increases?

    Correction:  last sentence should be "... I believe this is primarily due to the fact that la Ninas tend to dominate rather than el Ninos."  During the negative phase of the PDO, la Ninas are more common, el Ninos less so, and during la Ninas the ocean tends to store heat that is released during an el Nino.

    Regarding the relationship between el Ninos and the PDO, please see Comparing ENSO and PDO  and The Pacific Decadal Oscillation (Climate Impacts Group, University of Washington)

    However, there has also been talk of the character of ENSO changing as the result of global warming, where depending up the climate model, more "el Nino"-like or more "la Nina"-like conditions tend to dominate.

  26. Cornelius Breadbasket at 18:05 PM on 24 July 2013
    The climate change policy discussion I wish Andrew Neil would have on BBC

    Too many people will not have the time or depth of interest to follow the debunking of Andrew Neil's misrepresentation. In the spirit of the one-line responses here on Skeptical Science I suggest a link toi this excellent testimony by Dr Jennifer Francis.

  27. 2013 SkS Weekly News Roundup #29B

    CBDunkerson@15,

    You're absolutely correct. If you recall this fragment of the court decision:

    “Having been investigated by almost one dozen bodies due to accusations of fraud, and none of those investigations having found Plaintiff’s work to be fraudulent, it must be concluded that the accusations are provably false. Reference to Plaintiff, as a fraud is a misstatement of fact.”

    you can be confident that NRO and CEI defence as if their accusations of fraud were simply "opinions with rhetorical hyperbole" has already been rejected by the court. A "misstament of fact" simply means a "lie".

    Whether this legaly proven lie is a perjury depends on its context (i.e. if accompanied by statement of oath) which is unknown to me. Like you, I hope MM's lawyers don't overlook this opportunity and add the possible perjury to their case if there is a good stance for it.

  28. Timothy Chase at 17:55 PM on 24 July 2013
    Why doesn’t the temperature rise at the same rate that CO2 increases?

    David, you might want to check out:

    A Looming Climate Shift: Will Ocean Heat Come Back to Haunt us? by Rob Painting, 24 Jun 2013

    Basically, the Pacific Decadal Oscillation (or more recently "Interdecadal Pacific Oscillation) is in its negative phase, and during this time the ocean tends to store heat.  I may be wrong, but I believe this is primarily due to the fact that it la Ninas tend to dominate rather than el Ninos.

  29. Why doesn’t the temperature rise at the same rate that CO2 increases?

    What is the current thinking as to why the oceans are now absorbing more heat than in previous decades? Is it some process which is occurring in response to the last centurys rise in air temperatures, or is it possibly related to other factors and cycles like ocean currents etc.?

    What are there promising research projects trying to sort this out, and will they likely result in improved climate models which better understanding of the role of the oceans?

  30. Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature

    By the way I'm aware of two replies to this. 1) Its only four papers it does not change the overall result, and mistakes could equally have gone in the other direction as well. Moreover, denialists will have done their best to find or implicate every error they can, so these four might be the best they can come up with. 2) Since a sample of scientists were also contacted to rate their entire paper the fact that three scientists claim their paper argues somthing different to how SS classify it from the abstract does not matter because overall the findings from that method were 97.2% support from AGW.

    But. The problem as I see it is that one mistake appears to have been found, and three more uncomfortable classifications seem to have occured. The presence of these fairly obvious looking doubts does cast a worrying shadow over the study as a whole because the implication is if you can find some mistakes, you can probably find more. And rhetorically that kind of doubt is exactly what denialists feed on.

  31. The climate change policy discussion I wish Andrew Neil would have on BBC

    I'm with Dikran on his comment about the futility of trying to see signals among noisy data. Something interesting to do, however, is plot the monthly sattelite data...but do so using roughly 13-year rolling averages. Such an averaging time would roughly smooth out solar cycles. If you do this, you'll see a nearly linear, upward trend. And, this occurs whether or not 1998 is included in the data.

  32. Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature

    This issue may have been addressed, but denialists have picked around the edges of this study by arguing some papers were wrongly classifed. While the total number of such incorrect classifications amounts to only four papers (as far as I am aware so far) what seems to be powerful about this objection is that by finding possible small errors it implicates the accuracy and credibility of the study and its overall findings. The links are:

    http://www.webcitation.org/6Grmd4IOP

    http://notalotofpeopleknowthat.wordpress.com/2013/06/30/getting-to-the-bottom-of-cooks-97-lie/

    The latter reference involves only one paper but it does look like an incorrect classification, as far as I can tell. The former reference involves three papers where denialist scientists consider their entire paper and state it does not support AGW, when the SS study classified it as supporting AGW based upon the abstract. It just doesnt sound right that a denialist who rejects AGW would publish a paper with an abstract that supports AGW.

    What is the reply to this?

  33. 2013 SkS Weekly News Roundup #29B

    Andy Skuce - I would consider price supports, tax incentives, and the like all as various kinds of subsidies: artificially manipulated prices representing a cost to the government or someone else, which change the economic landscape in one direction or another. 

    I would agree with you and with JvD that "industrialized" only is the wrong grouping, considering that the majority (not all) of these subsidies are in the exporting nations - although I would note that tax policies and import/export barriers are additions in both industrial and undeveloped countries, likely not accounted for in the figures above. I cannot, however, consider a refusal to consider artificial commodity pricing as a subsidy anything other than absurd. Every analysis I have ever seen describes these as subsidies. Accusations claiming that discussions of these subsidies are "lies" are unreasonable. 

     

    scaddenp - Yes, commodities is the correct word, which for some reason I spaced on in my previous post. Commodities have a value established by supply and demand, artificially lowering those values is a subsidy, a cost. At the very least, the Saudi Economy and Planning Minister thinks so... and I will have to say I consider his take on the situation more supportable than (re)definitions discussed in this thread. 

  34. 2013 SkS Weekly News Roundup #29B

    When people discuss "subsidised public housing", does anybody stop to check whether the housing is being sold/rented below construction cost, or is it just a reflection of the fact that the cost is below market value and therefore represents a cost to the taxpayer?

    BTW, I suspect that it's actually a lot harder to work out the "true cost" of Saudi oil than is being suggested here, even if all cards were on the table. Even within my own business it's hard to work out the "true cost" of some things.

  35. 2013 SkS Weekly News Roundup #29B

    The Saudis certainly consider opportunity costs when they run the economics on solar versus oil-generated electricity. No doubt-oil-generated electricity is competitve with solar energy at marginal oil production costs, but solar probably wins if world prices for oil are used.

    It is true that the Saudis sell domestic gasoline at greatly below market prices to their own consumers and that could reasonably be construed as a wasteful subsidy. On the other hand, the consumers are also the owners of the oil, since Saudi Aramco is a state company, and Saudi citizens might think it only fair that they pay just for the production and refining costs of oil that they already own as a birthright.

    It's perhaps worth noting that N Americans are enjoying cheap natural gas at well below world gas prices. There's no direct cash subsidy here, but government reluctance to approve LNG export projects is certainly helping to shield consumers from paying world commodity prices.

    I agree with JvD that the original article was misleading on the level of fossil fuel subsidies in  industrialized nations. However, "lie" implies an intent to mislead and I'm not sure there is any evidence of that here, it was possibly just a mistake on the part of the journalist.

  36. The Economist Screws Up on the Draft IPCC AR5 Report and Climate Sensitivity

    ianw01,

    On rereading the posts and on closer look, it turns out I was wrong @8 (sorry) and you are right that the last plot is somewhat ambigous as to what those red points actually mean.

    I very much like jdixon1980@7 suggestion in the last paragraph to animate the graph over three sensitivities. That would remove the issue and enhance & clarify the graph at the same time.

  37. Timothy Chase at 10:43 AM on 24 July 2013
    Why doesn’t the temperature rise at the same rate that CO2 increases?

    gpwayne, I think it would be a good idea to at least briefly mention the point that the warming due to carbon dioxide being put into the atmosphere at any given moment doesn't happen immediately, but involves a certain lag, that it is warming "in the pipeline" due to it resulting in an imbalance in the rate at which energy enters and leaves the system, and that we only gradually accumulate the energy that warms the Earth up enough that it radiates energy at the same rate that energy is entering the system.  I believe this is at least as relevant as the point that the rise of temperature due to a rise in carbon dioxide is nonlinear.  You wouldn't have to include much additional material, though.  A brief mention and a link to where it is covered in more detail elsewhere at this site, such as:

    What the science says... The argument that "Earth hasn't warmed as much as expected" generally relies on ignoring the factors which have a cooling effect on the Earth's temperatures, and the planet's thermal inertia, which delays the full amount of global warming.

    in:

    Has Earth warmed as much as expected?

    http://www.skepticalscience.com/Earth-expected-global-warming.htm

    ... should be sufficient.

  38. The climate change policy discussion I wish Andrew Neil would have on BBC

    Just an FYI for Dana. You have been 'honored' with an original "Josh" cartoon over at Bishop Hill' blog. 

    http://bishophill.squarespace.com/blog/2013/7/23/you-get-what-you-pay-for-josh-230.html

     

    Hank.

  39. The climate change policy discussion I wish Andrew Neil would have on BBC

    Neil: "As pointed out above some scientists (and Mr Nuccitelli) believe that global warming is causing the depths of the oceans to heat up and that one day this heat will be released."

    It seems important to clearly explain that the ocean heat will not be 'released' as such. What will happen is that the ocean is expected to stop 'helping' us by absorbing as much heat as it does now, which means that more heat will go into the atmosphere. 

    .. and then I guess it wouldn't even be very 'helpful' if the oceans would (unlikely) continue absorbing heat at this rate, as that would increase the speed of sea level rise. So if we could worry less about atmospheric warming, we should probably need to worry more about sea level rise.

  40. 2013 SkS Weekly News Roundup #29B

    Not yet mentioned in this discussion of subsidies is the economic principle of opportunity cost.

    Opportunity cost is a somewhat hidden cost, when a choice is made between alternatives. If the choice that is made provides less return than other choices, then the person/entity making the choice is further behind - i.e., the choice actually cost them money, compared to the more advantageous choice. The classic example is the cost of keeping your money in your sock drawer. In one sense it "costs nothing", since you pay nothing out to keep it there - but you do "pay" the (now lost) income you would get if you invested that money somewhere where it would grow.

    In the case of the state-owned oil company that sells oil overseas for $100/barrel and sells it domestically for $30/b, there is an opportunity cost of $70/b for each domestic sale. The oil company's revenue is a source of income for the country, so each $70/b is lost, and to keep spending money at the same rate on other government functions, the money needs to come from somewhere else - perhaps taxes. If oil were sold at world rates locally, taxes could go down. This is a shift in the economics - the opportunity cost of selling domestically at lower rates is paid by other sources (perhaps taxes on alternative energy producers), who may or may not benefit from cheap gas.

    Whether you call it a subsidy or not is irrelevant - it is part of the economics.
     And it's "hidden" because you need to know where to look to see it.

  41. The climate change policy discussion I wish Andrew Neil would have on BBC

    Shuckman seems to have some 'interesting' sources as well 

    (hat tip Semyorka on the Guardian thread)

  42. Why doesn’t the temperature rise at the same rate that CO2 increases?

    For the sake of the example, suppose climate sensitivity is 30 for a doubling of CO2.  So from 200ppm to 400ppm we would see a temperature rise of 30.  We would then need to increase CO2 from 400ppm to 800ppm to see another 30.  In other words each additional increase in Carbon dioxide has less effect than a similar previous increase.  Of course this ignores an opposite effect, namely the inertia in the system.  The El'gygytgyn results hint that we should already be seeing more effects than we do.  It seems likely that we have set in motion a raft of interlocking feed back mechanisms that will have to work their way through before we are in equilibrium with 400ppm and hence be able to actually measure climate sensitivity. We won't be able to do this experiment since we are heading with gay abandon towards 500ppm and beyond. 

  43. 2013 SkS Weekly News Roundup #29B

    In your GM v Tesla analogy, I would argue that complaint would not be about price, but that GM's practices result in their employee buying more cars than they could otherwise afford. The complainent would not be Tesla but from makers of alternative forms of transport.

  44. 2013 SkS Weekly News Roundup #29B

    JvD - you are somehow confusing the cost of production with the price of a commodity. If demand for a commodity exceeds supply, then price rises till demand matches supply. If Saudi government removed that price support, then consumer cost would be higher and Saudi's would use less (and probably make better use of abundant solar). Therefore what they are doing is a subsidy and there would be less consumption if it were removed.

    You seem to be insisting a  special definition of subsidy. Lets not get hung up on definition. How about the claim then that goverments are providing $600B of various kinds of price support that, if removed, would increase consumer cost of fossil fuel, making other sources more competitive. Are you contesting this statement?

  45. The Economist Screws Up on the Draft IPCC AR5 Report and Climate Sensitivity

    Tom Curtis @12:

    I second ianw01@16 - I think that aligning the three data points vertically would add clarity rather than remove it.  Looking at the graph, I found myself second-guessing my understanding that the three data points were supposed to be all at the year 2100, because I could visually detect that they are not vertically aligned by noting the shrinking gap between the points and the right side of the graphic.    

    From the original article: "The figure below illustrates the amount of warming we can expect [my and ianw01's question is, by when? 2100?] if we continue on a business-as-usual path with continued reliance on fossil fuels and a slow transition to low-carbon energy sources (IPCC scenario RCP 6) for equilibrium climate sensitivities of 1.5°C (best case), 3°C (most likely), and 4.5°C (worst case), compared to the climate experienced during the history of human civilization." 

    If the RCP 6 scenario is supposed to be projected out to 2100 for each of the three climate sensitivities, how about showing three different curves, perhaps all red, but with a slightly lighter lineweight to avoid the "indistinguishable wedge" problem that Tom mentions?  Or even with the heavy lineweight, I think the overlap between the lines would be less confusing than the three points not being vertically aligned.  

    As still a third option, which would avoid the line-overlap/"indistinguishable wedge" problem, you could animate the graphic, cycling through the projections for the respective climate sensitivities, only displaying one at a time.  The legend itself could also cycle between "(RCP 6 scenario with 1.5 C sensitivity)," "(~ 3 C sensitivity)" and "(~ 4.5 C sensitivity)."  

  46. Dikran Marsupial at 03:30 AM on 24 July 2013
    The climate change policy discussion I wish Andrew Neil would have on BBC

    @jonthed The human eye is really good at detecting patterns in noise that don't exist.  In this case the perception of a plateau may be simply an artefact of the 1998 El-Nino spike.  If you blank out the spike, there is no longer much evidence of a plateau, just a steady increase at a fairly constant rate, with a bit of variability superimposed on top.

     

     

  47. Dikran Marsupial at 03:25 AM on 24 July 2013
    Empirical evidence that humans are causing global warming

    Matthew L: Not all speculation is idle.  Using your brain and having ideas is a good thing.  It is idle speculation when you don't test your assumptions or find out what scientists who have looked into the question have found out, or tested the consequences of their ideas.  I can assure you if you can produce a workable model that convincingly explains why mainstream science are mistaken about the causes of 20th century and current warming, academic journals would be keen to publish it and we would all be genuinely keen to read about it.  However, that takes a lot of work (on which the climatologists have commanding head start).

  48. The climate change policy discussion I wish Andrew Neil would have on BBC

    Can't the whole 'plateau' and 'mysterious ocean mechanisms' just be simply explained and put to bed for good by the fact that the ENSO has been mostly neutral or la nina since 1998 and that the temperatures are still rising on the same gradient for neutral an dla nina years, as shown perfectly in your graphic here on this site? 

    This one: http://skepticalscience.com/graphics.php?g=67

    surely this just shows that the whole 'plateau' is an illusion, that is fully explained and well understood? is it not?

  49. Empirical evidence that humans are causing global warming

    MatthewL:

    When I see an oscillation in temperatures from cooling (LIA) to warming (1850 - 1950) to cooling (1950 - 1980) to warming (1980 - 2000) to (possibly) cooling (2000 - ?) then it puts me in mind of a feedback effect. So, yes, I have used my own brain and had an idea. In your view is all speculation "idle"?

    Since you:

    (a) have asserted your speculation as fact ("For instance we have no way of telling whether the increase in temperature 1979 - 2000 is due [...]" - your words), and

    (b) have taken into account neither the responses of others in this thread nor the quantified radiative forcings applied to the Earth climate over this time frame (see a globally- and annually-averaged radiative forcing history in Figure 1 of this post, or a comparison of global mean temperature versus solar forcing here, or the inability of natural radiative forcings only to match the 20th-century observational record),

    I am comfortable in describing this specific speculation of yours as idle.

  50. Dikran Marsupial at 02:54 AM on 24 July 2013
    Empirical evidence that humans are causing global warming

    Matthew L, you obviously didn't see the point of my question.  The exchange of heat between the atmosphere and oceans is very sensitive to relatively small changes in ocean circulation, in particular ENSO.  This means that the oceans can equalise the the extra heat they have taken in really quite quickly.  It also means that it is not particularly difficult for small changes in ocean circulation (e.g. ENSO) to give rise to an apparent hiatus in global mean surface temperatures.  It is a pity that you can't see that uncertainties apply in both directions.

    As to the attribution of previous periods of warming or cooling, try reading chapter 9 of the most recent IPCC WG1 report.

    I agree with more funding for Prof. Trenberth though, science in general is rather underfunded.

    I also notice that you have ignored my challenge to give details of "a statistical test that establishes that there actually has been a hiatus in GMSTs and what we are seeing is not just an artefact of the noise? ".  You ought to ask yourself why it is that you are unable to answer this fairly basic question and yet seem quite confident of your own position on this.

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