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Comments 43351 to 43400:

43351. MA Rodger at 00:27 AM on 28 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       dvaytw @52.

       Oceans acting as the damper on any rising temperatures is not too difficult to establish. So a reference could well be found way back in time. But before 1997? Anything post 1990 will be preceeded by the IPCC FAR. A quick look at the Summary yields.

       IPCC WG1 1990 Policymakers' Summary p xxvi
       Info box - EQUILIBRIUM AND REALISED CLIMATE CHANGE
       "When the radiative forcing on the earth-atmosphere system is changed, for example by increasing greenhouse gas concentrations, the atmosphere will try to respond (by warming) immediately But the atmosphere is closely coupled to the oceans, so in order tor the air to be warmed by the greenhouse effect, the oceans also have to be warmed, because of their thermal capacity this takes decades or centuries This exchange of heat between atmosphere and ocean will act to slow down the temperature rise forced by the gieenhouse effect."
       IPCC WG1 Policymakers Summary p.xxix
       "Global-mean temperature alone is an inadequate indicator of greenhouse-gas-induced climatic change Identifying the causes of any global-mean temperatuie change requires examination ot other aspects ol the changing climate, particularly its spatial and temproal characterisitcs (and?) the man-made climate change signal."

43352. andrewii at 23:52 PM on 27 July 2013
       IPCC is alarmist
       

       Thanks DSL, gws and Glenn Tamblyn!

43353. Tom Dayton at 23:47 PM on 27 July 2013
       Murry Salby finds CO2 rise is natural
       

       Michaelf, a debunking by Masters and Benestad was published in the July issue of the same journal.  The article is paywalled, but Masters explained the approach on his blog, and Benestad debunked previous, annoyingly similar "work" by Humlum on RealClimate.  Masters discusses their Masters and Benestad critique on his blog, including a discussion by he and Richardson about the complementarity of their critiques.

       Moderator Response:

       [TD] Mark Richardson wrote a whole Skeptical Science post summarizing his comment.

43354. Tom Dayton at 23:39 PM on 27 July 2013
       Murry Salby finds CO2 rise is natural
       

       Michaelf, Mark Richardson debunked Humlum's 2013 article in the latest issue of the same journal.

       Moderator Response:

       [TD] Mark Richardson wrote a whole Skeptical Science post summarizing his comment.

43355. Russ R. at 21:33 PM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Andy,

       I apologize for not having read your previous post.  

       My rant was not directed at you.

43356. Michaelf at 19:18 PM on 27 July 2013
       Murry Salby finds CO2 rise is natural
       

       Just been pointed to this article that seems to support Salbys work. Do you have a rebuttal for its conclusions?

       http://www.sciencedirect.com/science/article/pii/S0921818112001658

       Moderator Response:

       [TD] Just more of the same for Humlum.  Search for "Humlum" on this page.  Also enter Humlum in the Search field at the top left of this page to find more.

       [TD] Sorry, I should caffeinate before typing in the morning.  Mark Richardson wrote a Skeptical Science post about this Humlum paper!

43357. chriskoz at 18:28 PM on 27 July 2013
       A tale told in maps and charts: Texas in the National Climate Assessment
       

       I have problem understaqnding the nomenclature of some figures.

       Figure 4.3 introduces "Cooling Degree Days" on the scale from 0 to 2800. What does it mean that CDD==2800? Per year is impossible, so maybe per decade or per the entire period shown?

       On the other hand, Figure 19.3 shown delta of "Number of Dry Days" on the scale from -8 to +6. Again, what does this measure mean? What was the base of that delta? Per year, per decade or per entire period like in the previous example?

       I cannot have a "feeling" as to the magnitude of those changes because the measures is so poorly defined that you don't really know what numbers they show.

       Is it only me having problems here ? Maybe someone else who understands the undefrlying research can explain the nukmbers to me...

43358. Andy Skuce at 16:31 PM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Russ R

       i suggest that you read the previous post I made on the subject just a few weeks ago. I addressed points 1 and 2 there, but probably, by the sound of it, not to your satisfaction. Yes there are other gasoline taxes apart from the carbon tax, some of them bigger in the Vancouver area. And yes, the decline in consumption is bigger than expected from what these taxes should produce according to standard models. 

       You should also read the working paper by Rivers and Schaufele that I linked to that discusses this issue at length. You may be interested to read there that they do not discount entirely the idea that cross-border gas fill-ups may have  played a role in the consumption reductions. They wrote:

       Two alternative explanations, cross-border shopping and contemporaneous vehicle efficiency policies, could also potentially explain our findings. Both are discussed in turn. We believe that neither is credible and think that there are good reasons to trust that it is the carbon tax that caused the change in consumer behaviour. The first alternative explanation is that the carbon tax coefficient is actually capturing a cross-border shopping effect. Higher prices due to the carbon tax may have encouraged drivers to begin filling their gas tanks in neighbouring jurisdictions. We are unable to dismiss this explanation, yet believe that it is unlikely. Alberta is to the east of BC, while Washington State is to the south. Both jurisdictions have had lower gasoline prices than BC for many years, including a lengthy period prior to the introduction to the carbon tax (refer to Panel B in Figure 1). Further, over 95% of BC’s population would need to drive more than two hours to reach the Alberta border, while crossing into Washington involves an international border. It is doubtful that a sizeable share of residents suddenly began cross-border shopping because of the carbon tax. Nonetheless, this is a potential alternative explanation for our findings.

       I understand that a peer-reviewed version of this paper is in the works. 

       Rather than jump to the conclusion that everyone here is gullible, you perhaps should have considered the possibility that some of us had already thought through some of these issues more thoroghly than you have. 

43359. dvaytw at 16:15 PM on 27 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       Thanks for all the info, guys.  

       The dude is also trying to say that the ocean heat content is just climatologists making AGW theory unfalsifiable by changing their story after the fact.  I recall there was a study quite a while back predicting oceans would take up most of the heat.  I know Hansen had something about this as early as 1997, but I remember there was something even earlier.  Does anyone know what this was?  

43360. Russ R. at 11:59 AM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       (-snip-).

       Rather, all of the skepticism has been directed at the small side-effect of leakage that I raised.

       (-snip-).

       1. You should maybe have been a bit skeptical about a claim that a ~5% carbon tax resulted in a ~19% decline in per capita fuel consumption. That would imply a long-run price elasticity equal to -3.8. That should have immediately raised a few eyebrows, since no econometric analysis has ever observed a sensitivity figure of nearly that magnitude... the median estimate for long-term fuel (gasoline) price elasticity is only around -0.5. (Source: Gasoline demand revisited: an international meta-analysis of elasticities, Molly Espey (1998) Fig. 2) That implies a ~5% increase in price should result in only a ~2.5% decline in consumption, certainly not ~19%. The authors themselves noted the reduction was 7.1x greater than expected, (-snip-).

       2. (-snip-) in 2010, Translink (the public transit authority) raised its vehicle fuel levy by 3 cents per litre, and by an additional 2 cents in 2012 on all gasoline and diesel sales in the South Coast region (covering all of Greater Vancouver) . (-snip-). (-snip-).

       3. I suggested that some amount of the massive decline should be attributed to people filling up their tanks outside the province... as a) there is a substantial tax gap, and b) the number of cross-border trips have more than doubled during the period. (-snip-). Never mind that Andy Skuce kindly supported my point @16.2, estimating that around 11% of the decline in domestic sales could be due to cross-border day trips by BC residents. I agreed that his estimate was reasonable, and pointed out @18.2, 18.3, 18.4 and 18.5 that there are at least 4 other smaller factors contributing to the decline in domestic sales, and suggested that he might want to consider them if he's going to be doing more detailed analysis. (-snip-). (-snip-).

       4. And then the clincher.... Tom Curtis @15 produced a historical gas price chart he pulled from gasbuddy.com showing that the spread between BC and Washington prices hasn't widened, rather it narrowed as much as 20% by his pixel counting method. And just like that, case closed. (-snip-)... except for one detail. The gas price differential didn't really narrow. (-snip-). Tom (-snip-): "When comparing US cities to Canadian cities you have a choice of price units. The standard unit of measure in the US is dollars per gallon and in Canada the standard is cents/liter. Comparison of US and Canadian cities is done using recent currency exchange rates and uses the conversion factor of 1 US gallon being equal to 3.78 liters."  Gasbuddy doesn't apply historical exchange rates. (-Snip-) But nobody here stopped to apply a moment of skepticism (or common sense). News reports of people lining up across the border to buy gas, people complaining of the rising tax gap, 400 thousand more trips per mont... but no... ignore all of those people. Tom concludes that LESS people bought gas because he downloaded a chart that he erroneously interpreted as evidence that the price differential had narrowed.  (-snip-).

       Moderator Response:

       [DB] Multiple inflammatory tone violations snipped.  Please familiarize yourself with this site's Comments Policy and comport future comments to comply with it (link adjacent to the user comment box).

43361. Brianc at 11:04 AM on 27 July 2013
       BC’s revenue-neutral carbon tax experiment, four years on: It’s working
       

       In 2008 1,714,031,000 liters of diesel fuel was sold in B.C. In 2011 2,221,338,000 were sold.

       I know this data doesn’t have 2012 but you’d have to have one heck of a drop to get over a forty percent drop in diesel fuel. It makes me wonder what data they are using, or maybe I’m using the wrong data.

       http://www.statcan.gc.ca/tables-tableaux/sum-som/l01/cst01/trade37c-eng.htm

43362. Andy Skuce at 09:33 AM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Tom, KR, Philippe,

       I disagree on a couple of points.

       One is that I think the data show that BC same-day crossing have gone up faster than elsewhere in Canada. Here's a plot I made. I did running 12 month sums of the monthly data, so the number of cossings is for a yearr centred on a given date.

       

       (Forgive the typo in the label.) The BC same-day trips increase from 2008 to 2012 more in absolute terms than the rest of Canada and in population relative terms much more. As I said above, I don't think this was driven significantly by the carbon tax. I would speculate that this is a result of other pressures and due to the fact that a lot bigger proportion of the population in BC live close to the border compared to other provinces and they can more easily respond to economic incentives by shopping in the US.

       But, regardless of the motivation for taking the additional trips, more people filling up in the US in 2012 than in 2008 would depress reported fuel sales in BC, other things being equal. The question is by how much. My provisional estimate is that this may account for a small part (about 10%)  of the observed decrease reported per-capita consumption relative to the rest of the country. The decrease reported since the introduction of the carbon tax is huge, 18.8%; if the cross-border-corrected number turns out to be 16%, it would still be a very large decline, far bigger than econometric models would predict from a carbon tax of $30/tonne.

43363. Philippe Chantreau at 06:24 AM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       "I'll add that the burn of driving to WA from BC would in general lose more than any advantage"

       Let's see, at about 7 cents a liter, the total on a 60 liters tank comes to $4.20, which would buy how much exactly? At $1.45 a liter, that would be less than 3 liters. And how much distance can be covered with that much gas in the kind of vehicle that has a 60 liters tank? 40 km at best in real conditions, perhaps 50 (I think that's overly generous). Therefore,  I estimate one would have to be within 18 to 24 km of the nearest station across the border (not the border itself) and avoid long waits to just break even. It would have to quite a bit closer to create a measurable gain and that gain would be so minimal that it becomes problematic to justify the hassle if no other factor is involved in the trip. The cost of mileage for the car (maintenance, tires, oil, etc) should be factored in too. 

        

       For anyone in Vancouver with that kind of vehicle, it seems it would be a total no brainer: not worth it. A vehicle with a 40 liters tank capacity and a 30 mpg mileage wouldn't give a much better deal. That's what I can come up with, in 3  minutes by head, based on an outlook from the Washington State side. I doubt that the numbers I'm not aware of (BC gas prices) are so off that they can radically change my conclusion but I'm open to better informed, more accurate calculations. 

43364. KR at 04:35 AM on 27 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       dvaytw - Note that the experimentally measured parameter that I discussed above is the thermal gradient of the ocean skin layer and its changes WRT downward atmospheric IR, averaged over multiple days. The gradient is the result of all acting processes, including IR, ocean turbulence, winds, evaporation and condensation, passing fish, etc - indicating that these other processes (while undoubtedly affecting the gradient to some degree) do not override or overwhelm the IR related changes.

       Any increase in evaporation in particular (one of the more common off-the-cuff objections to this information), results in its own increase in GHG absorption and re-radiation near the surface - increasing the IR input to the skin layer, and again acting to reduce the thermal gradient and ocean heat loss. 

43365. MA Rodger at 04:05 AM on 27 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       dvaytw @46.

       Courtesy of SkS, some light reading for you or your 'friend'. How Increasing CO2 Heats the Ocean.

43366. davidsanger at 03:20 AM on 27 July 2013
       Why doesn’t the temperature rise at the same rate that CO2 increases?
       

       Timothy @12 and Glenn @14
       
       Thanks for the explanation and references which led me to the Rob Painting posts, extensive comments, and the two Meehl papers (2011 and 2013). Very helpful.
       
       Modeling of the deep ocean currents and vertical mixing does indeed seem to be extraordinarily complicated and and I'm glad to see it's an area of ongoing development

43367. KR at 02:16 AM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Russ R. - What I said, and I thought I was being clear, is that given the lack of (and in fact reduction of from 10 yrs ago) differential in gasoline prices, there is little reason to expect significant gasoline purchasing in WA rather than BC. I'll add that the burn of driving to WA from BC would in general lose more than any advantage. 

       Additional information over and above the lack of economic gain: less increase in day trips to the US from BC than from Canada overall which by itself invalidates the hypothesis, and changes in exchange rate that seem far more likely to be the variable of interest in cross-border travel. 

       Do some people drive across the border to fill up? Of course - people do all kinds of things for all kinds of reasons. Is it significant as an economic influence? You have presented no evidence to that point, and the economics and travel data say otherwise. 

       Keep in mind that the carbon tax applies across the board - heating, electrical, industrial, etc. What percentage of the carbon reduction comes from those other sectors, from improved insulation, compact fluorescent lights, and so on? If you want to make a point regarding carbon leakage, find out if (and if so, show your data) whether the carbon tax has displaced electrical generation across the border. But the relative rate of cross-border trips from BC has not increased (it has decreased) relative to Canada overall during the period of the carbon tax, nor for that matter has Ontarios as far as I can see. There's no evidence for fill-up carbon leakage.

       You have (IMO) shifted back and forth from multiple data sources in an attempt to support your hypothesis, but (again, IMO) you have not succeeded in producing evidence.  

43368. Tom Curtis at 01:57 AM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Russ R @22, in your first post here you cited an article based on information from the Canadian Taxpayers Federation suggesting that a surge in British Columbians crossing the border was due to high tax rates on fuel in British Columbia.  Being fair, it may be.  The CTF cite high taxes in general, and it was you (SFAIK) who attributed that to the Carbon Tax specifically.  Regardless, we now know that the surge is almost entirely a function of changes in the exchange rate, and that the price differential on fuel between BC and WA is at least not unusual, and so cannot be the cause of the surge.  In fact the cause is (at least mostly) changes in the exchange rate.

       It took about twenty minutes to gather together and present the data to determine that.  Nor is it a tricky operation.  Normalizing the data involved subtracting from each entry the mean of the column, then dividing by the standard deviation of the column.  It is the sort of thing any bright twelth year student could do, and quite a few grade ten students as well.  I am certain I could talk my youngest daughter (grade 10), who is currently learning how to use the ANOVA function, through the proceedure in no time flat if she had the slightest interest in the procedure.

       So the question is, why did not the CTF do it?  By not doing it, the simply took two random facts and combined them to make an argument that was clearly not justified by the data they used.  Indeed, with full context, the argument was refuted by the data they used.  How is that not an unsubstantiated argument?  How is the argument not bullshit when it is refuted by the very data presented as establishing it?

       What this episode tells me about the CTF is that they prefer propoganda to understanding.  I know this because either they did not do the analysis, or they did.  In the latter case they knew the argument was not supported by the data, but presented it anyway in what could only be called a deliberate lie.  In the former case, the merely found data that could be construed as supporting their argument, and did not bother checking whether it did or not.  The truth of the matter was immaterial to them, at least when set against the imperative of getting their message out.

       What it tells me about the CTV British Columbia was that it had a massive failure of editorial standards.  A type of failure, I might add, which seems like standard practise for most news organizations nowadays - who again appear to have no concern that what they report is true, merely that it gain viewers or readers.

       Despite the apparent moral bankruptcy of the CTF and CTV British Columbia, however, I did not make my statement merely on establishing their original unsubstantiated story was false.  It was not until I established that the change in relative prices was opposite to that which might be naively supposed that I insisted that anybody mounting the argument without a proper statistical analysis is spreading sunsubtantiated bullshit.  The significance is that that unexpected change in price differential undercuts the logic of the argument entirely.  So, we are not in a position of ignorance anymore.  We have good reason to believe the fundamental premise of the argument is false.  But you still think its OK to spread the argument without any sort of analysis to show the argument is, despite the information we have to hand, still valid?  Or indeed, that it is OK to set yourself up as knowledgable on this topic by presenting the argument without having first taken the twenty minutes it requires to check your facts?

       Frankly, if that is your approach, I don't care for your good opinion.

       I do care about truth, and repudiate utterly the idea that it is OK to ride roughshod over it as a means to an end as the CTF and CTV BC have done in this case. 

43369. Russ R. at 01:37 AM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       KR,

       "I see no justification for claiming carbon taxes have driven the BC population to displace significant gasoline purchases, 'carbon leakage', to Washington state. The price differential doesn't support it, and in my opinion more supporting data is needed before accepting such a claim. "

       Let me get this straight... you have no skepticism about a claim that a rougly 7¢ per litre carbon tax is responsible for a huge (18.8%) relative reduction in per capita fuel consumption and are willing to accept it at face value, but you won't accept that some amount of that reduction should be attributed to leakage?

       Is that about right?

43370. KR at 01:16 AM on 27 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       dvaytw - I took a look at your discussion, and have some comments.

       • The oceans represent about 93% of the climate thermal mass. Ignore 90+% of the climate at your peril. 
       • Ocean energy, and temperatures, continue to rise throughout measured depths. That includes waters below 2000m, see Pukey et al 2010 on abyssal temperatures.
       • Focusing only on air temperatures and their short term variations (under 25-30 years) is a fools game; you can choose any apparent trend you want out of short term noise. That's one advantage of ocean heat content as a measure - the oceans have tremendous thermal inertia and lower short term variability as a result. 
       • No matter how you parse Eschenbachs graphs, the oceans are warming at a rate that has been quite stable over the last half century. 
       • If you look at sufficient air temperature data for statistical significance, or account for even some of the variability to look at shorter terms (Rahmstorf et al 2012), you see that the air is also continuing to warm at a stable rate. 

       If your friend wants to discuss science, he's welcome to read or engage in topics on SkS, or RealClimate, where points are best backed by published peer-reviewed science and data. Rather than WUWT, where bloggers toss off the random and (a critical point here) contradictory objections of the day, and the wildest unsupportable hypotheses hold sway. 

43371. Bob Loblaw at 01:07 AM on 27 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Russ R @ 22:

       That's odd. When I read Tom saying that, I thought is represented a very succinct summary.

43372. Bob Loblaw at 01:04 AM on 27 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       dvaytw:

       Nobody "forgets" evaporation. Nobody ignores thermal loss to the atmosphere, either. Everyone looks at the enire energy balance in their models/analysis:

       - absorption of solar radiation (can penetrate metres, as pointed out)

       - reflection of solar radiation (energy that arrives at the surface, but immediately is lost again)

       - absorption of IR radiation (a few mm)

       - emission of IR radiation

       - evaporation (an energy transfer to the atmosphere, due to the latent heat of evaporation)

       - thermal transfer to the atmosphere (driven by turbulent mixing in the atmosphere)

       - and finally, thermal transfer ito the ocean (conduction, turbulent mixing, etc.)

       None of these exists in isolation. Change one, and all are likely to change in response. Increase the downward IR absorbed at the surface, and the energy has to go somewhere. If the water surface temperature increases, then the likely response is that emitted IR will increase, thermal losses to the atmosphere will increase, and thermal transfer into the ocean will increase as well.

       Your "opponent" is suffering from Single Factor Syndrome, where he/she thinks that compartmentalizing your thinking to look at only a small part of the picture means that the rest doesn't matter. The statement "Greenhouse radiation will only increase that evaporation" is just simply wrong. The word "only" is the warning flag: as soon as someone thinks that there is only one factor in climate, they are mostly likely talking through their hat.

43373. KR at 00:44 AM on 27 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       dvaytw - See How Increasing Carbon Dioxide Heats The Ocean, or the RealClimate Why greenhouse gases heat the ocean posts. 

       Long story short - IR gets absorbed in the first millimeter or so of water, visible light penetrates a few meters. But that surface layer, with surface tension, is relatively stable (not turbulent), heat from solar warming has to go through the skin layer by relatively inefficient thermal conduction, not mixing or radiation, and the downward IR from the atmosphere reduces the thermal gradient across that last millimeter and hence the ability of the oceans to lose energy. Conduction is a function of thermal conductivity and of gradient; IR decreases the gradient and slows cooling. 

       Hence the oceans gain energy until the increased temperature of the ocean re-establishes a thermal gradient across that skin layer once again sufficient for the oceans to lose as much energy as they gain from the sun - warmer waters. 

       I will note that this surface layer effect is experimentally confirmed. 

43374. dvaytw at 00:10 AM on 27 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       KR and MA Rodger thanks for the feedback.  

       I actually relayed KR's response directly and he said some stuff back.  I feel silly copying back and forth, but if anyone's interested, the debate is here:

       http://www.forumosa.com/taiwan/viewtopic.php?f=86&t=120785&start=250

       He and I get into it about ocean heat content on page 25 (if you want to comment, I think you can do so as a guest poster.)  

       Most of what he said suggests to me he doesn't really understand what KR said, but I would like to ask about this one thing:

       "Of course we all know that the sun's radiation has effect on the oceans, especially on the top layers. To count the energy on the top layers and combine it with the energy rise in the deep ocean, which they hope is caused by greenhouse gases, is deceptive.

       The radiation caused by greenhouse gases, on the other hand, is very shallow and only hits the surface, compared to that of the sun, which goes in deeper. What they often forget is that surface water evaporates. Greenhouse radiation will only increase that evaporation, carrying away that precious energy back into the sky."

       That bit about deep and shallow penetrating radiation... is there any truth to that?  

43375. KR at 23:54 PM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       I believe the gas price differential between BC and WA, or for that matter between Vancouver and Seattle, indicates that there is little if any economic justification for driving across the border merely to fill the tank. 10 years ago (prior to the carbon tax) the Vancouver price was about 2x the US price, currently it's ~1.5x the US price, and has remained between roughly 1.3-1.5x over much of the last six years.

       I see no justification for claiming carbon taxes have driven the BC population to displace significant gasoline purchases, 'carbon leakage', to Washington state. The price differential doesn't support it, and in my opinion more supporting data is needed before accepting such a claim. 

43376. KR at 23:06 PM on 26 July 2013
       CO2 effect is saturated
       

       As Tom Curtis correctly points out, the LBL codes are quite accurate and are direct computations from the spetroscopy, not complex models, confirmed by satellite meaasures. And the primary uncertainty in direct effects is from varying composition of the atmosphere, not the LBL models. 

       However - the uncertainties (+/- 5-10%?) in direct forcing are once again smaller than, and subsumed by, uncertainties in climate sensitivity, which is estimated at 2°C to 4.5°C per CO2 doubling. A high estimate in direct CO2 forcing will lower the CS estimate, and vice versa, as they are related by the total effects on the climate. 

       So: ΔF = 5.35*ln(C/C0) W/m² is a demonstrably solid estimate for CO2 direct forcing, quite small uncertainties, and incidentally not affected by the computation methods of GCMs. To bring this discussion back to the opening post, CO2 direct forcing is by no means saturated; it has a logarithmic relationship to CO2 concentration. And the total effects on the climate of GHG increases are bounded by climate sensitivity, not the far far smaller uncertainties with line-by-line radiative code. 

       Can we leave this particular dead horse in peace now?

43377. Russ R. at 22:19 PM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Tom Curtis,

       "I and anybody else following this excercise would be quite justified in dismissing it as unsubstantiated bullshit."

       I have to say, I was very impressed with your responses right up until that.  

43378. Tom Dayton at 21:47 PM on 26 July 2013
       CO2 effect is saturated
       

       Stealth, in addition to Tom Curtis's excellent reply to you, see Chris Colose's post "Adding Up the Greenhouse Effect: Attributing the Contributions," being sure to click on his links to coverage of that topic by RealClimate among others.

43379. Paul Barry at 20:59 PM on 26 July 2013
       The Consensus Project data visualisation - a history
       

       The consensus project is good work. Just a couple of comments - late to this post.

       (1) I'm not sure everyone loves interactive or animated graphics. Many people find animated graphics a little annoying and prefer to see all of the data in a simple static graph or chart. Animated, novel graphics appeal to people who perhaps are unused to examining data and graphs, but others prefer to look at old-fashioned, "professional-looking" static graphs (think of all those analysts who look at economic and financial data) that don't move about. It would be very useful to provide some nice static graphics using other formats too: trend lines, bars etc. which could be reproduced and published elsewhere easily.

       
       (2) Many with a scientific bent (if not necessarily a good understanding of the science) will be more curious about the 3% of the papers expressing an opinion which rejected the consensus - the "outliers".

       Of the 11944 abstracts analysed in the Cook paper, these amount to 0.3% or 36 papers. 36 might even sound like a significant number of papers to some who may adopt what they believe to be a Popperian approach believing that just one paper is all that is required to "falsify" the consensus!

       It would be nice to get more information on these papers. How many people are behind them? Are they they the usual suspects? It could be useful too to compile some data on them answering questions like the following:

       (1) How many of these papers had their findings refuted or superceded subsequently by others? (2) What arguments/evidence do they papers put forward to contradict the consensus on climate change (3) To what extent to they deviate from the consensus position.

       There being only 36 of them, it should not be too difficult to do this kind of analysis. Perhaps someone already has?

43380. Tom Curtis at 18:58 PM on 26 July 2013
       The Economist Screws Up on the Draft IPCC AR5 Report and Climate Sensitivity
       

       Richard Lawson @24, a dedicated question page would be a nice addition to SkS, and has been suggested before.  It, like a number of other good suggestions has been side lined because the time available from volunteers is limited, and a number of other very worthwhile projects have been pursued instead.  (The Consensus Project comes to mind.)  However, we live in hope, and as I am not in on current planning, one may be coming soon (or not).

43381. Richard Lawson at 18:32 PM on 26 July 2013
       The Economist Screws Up on the Draft IPCC AR5 Report and Climate Sensitivity
       

       Tom Curtis @21. Many thanks again for your response. Yes, the impression I had was from the discussion on CS that is penetrating through to the general news, where the picture is that CS values are being revised downwards by recent work. It was an Economist article that stated that EB models gave lower values than GCM models.

       There are a few of us out here, non climatologists who are engaging in the thankless and often depressing task of debating with delayers on blogs and Twitter. We do search sks &c for answers, but there is often no answer to a specific question, which is why it is so useful to be able to put questions here.

       It might be useful if sks had a dedicated standing page for us to put questions which arise from the debate. 

43382. Tom Curtis at 17:49 PM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Andy Skuce has drawn my attention to an error in my calculation @14.  In fact, in BC 36,000 million vehicle-kilometers were driven, ie, the aggragate of all kilometers by all vehicles 4.5 tonnes and smaller was 36 billion km, not as I had mistakenly interpreted it an average per vehicle of 36,000 km.  That means the real average per vehicle was 13, 850 km, or just over 1150 km per month.   The net effect is to increase the upper bound of BC fuel purchased from US pumps to 21.6%, if we remember to allow for the additional correction discussed @20.1

       This correction has no impact on estimates of carbon leakage, ie, additional fuel purchased outside the taxed area in order to avoid the tax.  Because US prices have always been cheaper than BC prices, and because for most of the period of the tax, the price differential has decreased (see @14 {third paragraph} and @20.6 above) there will be effectively no carbon leakage other than a small amount across provincial borders that is severely restricted by population distribution.  Nevertheless, it will impact assessments of the tax in another way.  Specifically, by reducing the proportion of the BC economy directly effected by the tax, it reduces the effective tax rate by a small (and difficult to calculate) amount.  The economic impact would be equivalent to the situation if all fuel were purchased in BC, but the tax rate was X% less, where X depends on the actual proportion of fuel purchased outside British Columbia, and the proportion of fuel expenditure as part of the total economy.

       I would like to thank both Andy and Russ for picking up on my errors so that they could be corrected promptly.

43383. Tom Curtis at 16:00 PM on 26 July 2013
       CO2 effect is saturated
       

       Stealth @261:

       1)  You appear to not understand what models are.  They are simply the worked out predictions of scientific hypotheses.  In the case of LBL models, they are the worked out predictions of hypotheses that have been repeatedly tested to very greate detail in laboratories along with more or less accurate estimates of atmospheric temperature, humidity and gas concentration profiles.  The working out is not mathematically complex, although it is tedious.  Nor is it chaotic, so errors in initial conditions will be proportional to errors in the final results.  In that context, saying that an LBL model predicts something is no different from saying that the only well confirmed radiation theory predicts that thing.  It would be like disputing the planned trajectories of space craft as entirely hypothetical because they were worked out on a computer using only Newton's laws of graviation and the known masses and trajectories.  Indeed, more absurd in that Newton's laws of gravitation and motion for more than two bodies and a sufficient time are chaotic.

       2)  Despite that, satellite observations have been used to directly confirm the accuracy of LBL models.  One of the earliest attempts to do so was published in 1970:

        

       In this case, the data about temperature and humidity profiles was gathered by a radiosonde near simultaneiously with the satellite observation.  The accuracy, even back in 1970, was extraordinary.

       More recently (2008), a comparison between two LBL models and satellite observations was made.  The following is a scatterplot of measured OLR for 134,862 observations between the satellite and the more accurate of the two LBL models:

        

       And here is a fuller comparison of both models with the satelite:

       

       Note that the least accurate of the two models is never less accurate than 1.33% error, while the more accurate is never less accurate than 0.33% error.

       Similar comparisons can be found for even broad band models such as Modtran:

       

       Broadband models use the same well understood physics as LBL models, but use simplifying approximations to reduce the number of calculations needed.

       It should be very clear from this that uncertainty from radiative models is almost entirely from uncertainty about the specific composition of the atmosphere; and that Myhre et al's model based estimate of 3.7 W/m^2 +/-10% is sufficiently justified by the data.

       3)  Your suggestion that estimates of the CO2 contribution appears to be based solely on Lindzen's 1991 throw away comment.  Certainly the 1990 IPCC (Houghton) estimate of 60-70% water vapour and cloud contribution is reasonably close to the 1997 Khiel and Trenberth estimate of 72-79%, which is yet closer to the Schmidt et al 2010 estimate 75%.  That seems like a fairly smooth refinement of a value as methods (and computers) improve, with the initial estimate being by no means unreasonable.

       In contrast Lindzen's "estimate" has no basis.  He does not even provide sufficient information as to how the estimate was done to know whether he was estimating the current increase in radiative forcing of CO2 as a proportion of the total greenhouse effect (as assumed by Schmidt et al), or whether he estimated the relative contributions to back radiation (as I have previously assumed).  In the first case he is, completely without warrant, assuming that H2O and clouds accounted for 100% of the natural greenhouse effect.  In the latter case he is showing a fundamental misunderstanding about the nature of the greenhouse effect (which is about the TOA energy balance).  In neither case is his estimate a scientific estimate because he has not provided the necessary detail for reproducibility.

       What is more, you are showing a throrough inconsistency.  You are calling into doubt detailed and accurate estimates because they are "model based", but are prepared to give Lindzen's "estimate" credence when it appears to be based on no more than a back of the envelope calculation.  Frankly, all Lindzen's estimate shows is that he stopped doing science and became a simple denier far earlier in his career than I had previously estimated.

43384. Tom Curtis at 15:12 PM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Russ R @18:

       1)  I apologize.  You are correct.  I merely looked for the most recent data without comparing the date to the border crossing data (for which I plead tiredness).  Extending the vehicle data back to 2005 (the earliest year with data in html format) to establish a trend, and allowing somewhat crudely for the decreasing trend in new vehicle ownerships, I have recalculated the value for the last 12 month interval as 33%, yielding an approximately 8.3% upperbound on US purchases of BC fuel.  Of that some small fraction may be an increase due to the Carbon Tax (but see 6 below).

       2)  We have indeed neglected provincial border crossings.  I have done so based on your contention above that the major population center in BC is very close to Washington State, and ergo relatively distant from provincial borders.  Indeed, no major BC city is close to a provincial border, and for the most part they need to cross a mountain range to enter Alberta.  I suspect this term can be neglected as well within error of the first term.

       3)  While we have neglected this term, the usual pattern for people taking a day trip is to fill up before leaving.  This must be especially the case when there is a substantial price hike on crossing the border, a pattern that has been the case for at least a decade.  Therefore negligible numbers of US citizens entering BC for day trips will started filling up before crossing the border when previously they filled up in BC.

       4)  As >48 hours requires at least a long weekend, such trips require specific planning and will only occur, for most people a few times a year.  Again the impact will be negligible.

       5)  Again we have ignored this factor, but again the impact will be negligible for similar reasons to those given in (3).  IE, the price advantage would already have made this the dominant pattern of behaviour before the carbon tax, and is not likely to have much changed after the carbon tax.

       6)  This whole discussion todate has been premised on the assumption that the carbon tax made BC fuel more expensive relative to Washington State fuel.  I have already alluded to the possibility that this is not the case based on the chart shown @15.  In fact, measuring by pixel count at peaks in that chart, I find that there is an approximate 20% fall in the price differential over much of the period post Carbon Tax relative to that prior to the Carbon Tax, although in 2013 prices returned to there former margin.  That means prices have moved in the opposite direction to that which you have supposed.  Therefore, if anything, over the period of the tax less BC fuel would have come from US pumps than prior to the case, although no doubt for reasons other than the tax.  This would have lead to an increase in fuel purchases in BC, rather than a reduction so that we must suppose the Carbon Tax to have been even more effective than we imagined based on naive assumptions.

       I would like to confirm this for you with a better statistical method than pixel counting, but gasbuddy charge for the data (and at quite a steep rate).  I will note, however, that it is incumbent on people making the argument that changes in cross border fuel purchases have limitted the effectiveness of the carbon tax to provide the relevant data.  Given the chart above, and absent an actual statistical analysis of the data, I and anybody else following this excercise would be quite justified in dismissing it as unsubstantiated bullshit.

       For what it is worth, there has been a substantial and obvious increase in BC fuel prices relative to Alberta since the introduction of the Carbon Tax, but that is of limited concern given the relative locations of the BC population.

43385. Russ R. at 14:19 PM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Andy Skuce,

       ...estimated this way, the increase in cross-border shopping would amount to approximately 11% of the drop in fuel sales in BC.

       Your estimate of 11% of the reported drop in fuel sales sounds pretty reasonable for BC drivers going to the US.  Please see my notes to Tom Curtis above, as there may be other factors you might wish to include in your calculations.

       It is worth noting that cross-border traffic has recently increased in other non-carbon-taxed Canadian provinces also.

       It's also worth noting that starting in 2010 Ontario applied a tax on fuel (and a bunch of other things) amounting to 8% (an even bigger increase than the BC carbon tax), so comparing changes in BC to the rest of Canada isn't a perfectly controlled experiment.

       I live in Toronto, and I've certainly been doing more frequent trips to Buffalo.  I go for more than just gas, but I routinely fill up my gas tank every time, just before I return.

43386. Russ R. at 13:50 PM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Tom Curtis,

       Again, let me compliment your analysis.  I only have a few minor points to add:

       1.  Your calculation of 14.4% of vehicles doing a cross border day-trip was for 2009, the lowest year in the data set.  The number of visits has more than doubled since then.  That percentage would be substantially higher today (assuming the size of the BC vehicle fleet hasn't also doubled.)

       2.  Our analysis has only focused on BC residents buying gas in the US (Washington and Alaska).  We've neglected British Columbians driving across the provincial borders, and I have no idea how many of those there would be.

       3.  We've also entirely neglected the flipside of the coin... a decline in BC gasoline bought by visitors to the province, who instead wait until they get back home before filling up where it's cheaper.  (StatsCan also has data for US residents visiting BC by car.)

       4.  We've ignored multi-day trips.  These are probably material because Canadian residents have higher duty-free allowances (especially for alcohol and tobacco) if they've been out of the country for at least 48 hours.  Looking back at the StatsCan data, the number of multi-day trips has also approximatly doubled (and yes, the exchange rate is most likely the dominant factor) and these people will also be buying gas.

       5.  We haven't at all accounted for commercial vehicles... truckers are pretty price sensitive when it comes to fuel, as they have greater fuel capacity and range and will likely have more opportunities to fill up outside the province rather than in it.

       My point with all of this is, it's impossible to calculate the magnitude of "leakage" and pretty complicated to even estimate it, but it is obviously a factor (as the lineups at gas stations across the border will attest) and the article makes zero mention of it.  They simply assume that 100% of the reduction in domestic fuel sales translates into lower consumption and emissions.  Remember, if the tax is high enough to encourage people to change their behaviour and consume less fuel, then it's also high enough to encourage people to buy more of their fuel outside of the province.  Both result in lower domestic fuel sales, but only the former results in lower emissions.

       I'll close by saying that I'm not at all opposed to the carbon tax, but only because it has maintained its revenue-neutrality.  I would probably have distributed the tax rebates differently than BC chose to, but I pretty firmly believe it's more economically sensible to tax consumption than to tax income.

43387. DSL at 13:25 PM on 26 July 2013
       CO2 effect is saturated
       

       SASM, is this what you're looking for: http://www.cccma.ec.gc.ca/papers/jli/pdf/puckrin2004.pdf?

43388. StealthAircraftSoftwareModeler at 12:58 PM on 26 July 2013
       CO2 effect is saturated
       

       Moderator [TD] @260: My apologies; I will try harder to stay on topic.

       Back to the CO2 forcing equation: ΔF = 5.35*ln(C/C0) W/m2

       I have read the Myhre 1998 paper, and it appears that the 5.35 coefficient was derived from a combination of using LBL, BBM, NBM, and HITRAN models.

       I have read the Schmidt 2010 paper (http://meteo.lcd.lu/globalwarming/Schmidt/attribution_present_GH_effect_2010.pdf) and it uses the NASA GISS ModelE as an attempt to arrive at CO2 affect at absorbing IR radiation. The paper also references peer reviewed sources for CO2 effects that are all over the map: Houghton 1990 states water vapor is 60% to 70% of the greenhouse effect and CO2 is 25%. Lindzen 1991 states water vapor is 98% and CO is 2%. The effects of clear sky, clouds, water vapor distribution vary enormously. Schmidt also states that many “cloud treatments tended to be quite simple.”

       It appears that coefficients for the CO2 forcing function equation have been derived from models -- is this true, or have I misread these papers? Are there any empirical measurements made with any land or space based instruments, and if so, how did they separate out CO2 absorption from IR absorption of other gases?

43389. Andy Skuce at 06:33 AM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Russ R @7

       I also pass through Tsawwassen frequently to catch the ferry to Vancouver Island. Although the Shell station in Point Roberts is only a mile or two out of my way, I have never filled up there, partly because I don`t usually carry my passport with me on trips to Vancouver. I note that the gas price at that station is very high by Washington standards, $4.69 a US gallon, probably because Point Roberts is a pene-exclave of the US (that was a new word for me too!) and it's a 35 minute one-way drive (not counting two border crossings) for Point Roberts drivers to get cheaper gas in Blaine WA. And the gas in Blaine is 50 cents per gallon more than in Seattle.

       If my Toyota Yaris was 3/4 empty I could buy maybe 32 litres at Point Roberts and save just over $4 compared to gas prices in Victoria. It's not worth the hassle to cross the border twice for that. But if I lived in Tsawwassen and had a Nexus card, I probably would fill up there from time to time.

43390. scaddenp at 06:23 AM on 26 July 2013
       2013 SkS Weekly News Roundup #29B
       

       JvD - cost of production for puposes of supplying energy need is frankly pretty much irrelevant. What matters in terms of consumer choice is price that they are able to buy power.

       You are avoiding the main question here. I assume that you do in fact agree that removing price support will result in energy cost of FF fuel go up? And that this will make renewables cheaper? And that higher cost of FF will result in less consumption? If you agree with this, then removing these forms of price support will be an effective means of reducing CO2 emissions.

43391. Andy Skuce at 05:50 AM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       When thinking about cross-border shopping, we have to separate out two different issues:

       1) Has the carbon tax, by itself, driven the recent increase in cross-border shopping trips?

       Short answer: a bit, but it is probably not the dominant factor.

       The carbon tax has added about 8 cents per litre (about 30 cents a US gallon) to the cost of gasoline. A 60 litre/16 US gal fill up across the border would save $5 in avoided carbon taxes.  Most BC drivers would burn more money than this  in gas just driving to the US and back to fill up. It would take most people at least an hour to do the round trip. So, clearly, few people would be motivated solely by the gas tax to cross the border.

       But added to the other incentives to shop in the US, including other taxes on gasoline and cheaper groceries, electronics, booze and cigarettes, the carbon tax adds a small extra incentive.

       It is worth noting that cross-border traffic has recently increased in other non-carbon-taxed Canadian provinces also. In addition, the number of border crossing was higher everywhere in the early 1990's than today, which time also coincided with a spike in the value of the Canadian dollar, as Tom noted for more recent periods.

       2) Does the recent increase in one-day cross-border trips account for the drop in BC fuel sales?

       Short answer: it probably accounts for up to 10% of the measured drop in consumption. But it`s not possible to calculate this exactly.

       There were 2.3 million one-day car trips by Canadians between BC and the US in 2007 and 5.7 such trips in 2011. Thats an increase of 3.4 million trips per year.  That means that, averaged over the BC population of 4.6 million, there were about 0.74 extra car trips per capita per year. If you assume that the average person fills up a car gas tank 12 times per year and that every extra one-day trip to the US results in a fill up, that would mean about 6% of the fill ups made by BC drivers since the carbon tax was introduced might have been done in the US.

       Alternatively, if every one of those extra cross-border trips resulted in an average 60 litre (16 US gallon) fill up, then that makes about 200 million additional litres of fuel purchased annually. On a per-capita basis that amounts to about 44 litres per person per year. The graph labelled Figure 1 in the original post shows that per-capita fuel consumption has dropped by about 0.4 cubic metres per year, or 400 litres per person per year. Therefore, estimated this way, the increase in cross-border shopping would amount to approximately 11% of the drop in fuel sales in BC.

       Of course, some extra fuel is consumed in making all of these extra trips, at, let`s say, 8 litres per round trip, that would amount to 27 million litres, so not all of the fuel purchased in the US reduces net fuel sales in BC.

       I plan to do a more detailed calculation and I`ll post it on my blog when it is done. I will provide a link here, in a week or so. These are rough calculations only and are dependent on my assumptions, so please treat them as provisional.

43392. Rob Nicholls at 05:06 AM on 26 July 2013
       The climate change policy discussion I wish Andrew Neil would have on BBC
       

       Plus ca change. I saw Andrew Neil repeatedly asking the UK's Green Party Leader Caroline Lucas "Why has there been no statistically significant warming for 15 years?" on a programme called "Hardtalk" in 2010. I wrote to the BBC at the time pointing out that the audience was likely to have been severely misled by this question, that the warming over the previous 16 years reached a conventional threshold of statistical significance (p<0.05), and that over a short timescale natural causes of variability (ENSO, volcanoes, the solar cycle) tend to predominate, so the short answer is "15 years is too small a sample to demonstrate statistical significance." (I had no idea at the time how much the ocean is warming and how high a proportion of the warming goes into the ocean). 2010 proved to have the highest measured global surface temperatures ever according to some data sets, but alas, still the line of questioning persists. (Short term variability really is the gift that keeps on giving).

       If Andrew Neil knew more about the science he might understand 1) how biased a perspective his chosen lines of questioning sometimes give on AGW, 2) that the IPCC's (AR4) suggested range for climate sensitivity is in line with the large body of evidence on the subject, and 2) how out on a limb scientists such as Judith Curry and Roy Spencer are from the mainstream evidence-based consensus.

       This is why Skeptical Science is so important. To the uninitiated with no grasp of the vast weight of science behind the consensus on climate change, Curry and Spencer sound completely reasonable (although if you're aware of some of the science and actually bother to do a little digging you find the context of where they're coming from and IMHO their credibility is somewhat lost). Without websites like SKS, far more people would be taken in by the denial of dangerous AGW.

43393. Tom Curtis at 05:02 AM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Here is the gassbuddy comparison chart for fuel prices between British Columbia and Washington State:

       

       I should have included in the prior post, but plead tiredness and insomnia (the only reason I am posting at this time) as an excuse for my poor composition.

43394. Tom Curtis at 04:57 AM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Russ R @13, as of 2009 (most recent data), BC had 2.6 million light vehicles.  They drove an average of 36,000 km per year, or 3,000 km per month.  That is equivalent to about four tankfulls a month.  In 2009, there were an average of 375,000 one day drive trips to the US from British Columbia, representing  14.4% of all vehicles (assuming for ease of calculation no more than one trip per vehicle).  That indicates that approximately 3.6% of all fuel used by BC vehicles was likely purchased on return from a trip to the US, assuming nearly all vehicles did so.  Let's call it 4%.

       As the trips were for the most part not to get the fuel, and as fuels prices have been cheaper in Washington State than in British Columbia in US$ per gallon for the entirety of the last ten years (and by approximately the same margin), we can assume that that pattern has been consistent through time since before the introduction of the Carbon Tax.  The effect of the Carbon Tax is not, therefore, the approximately 4% of fuel used by British Columbia cars that was purchased in the US, but rather the change in that figure.  In other words, it is significantly less than 4% of total fuel use on British Columbia roads.

       I have no doubt that fuel purchases in the US by British Columbians will have increased by some small margin due to the Carbon Tax.  It is not as much as you suppose because the change in the price differential before and after tax is small (to small to pick by eye of a chart).  Further, it is not as much as you suppose because US service stations close to the border probably have higher than average prices to exploit the BC market, and BC stations close to the border probably have lower than average prices to claw back market share against US competition.  It is certainly much less than 4% of BC fuel use, and hence cannot account for the approximately 20% fall in fuel use* in BC over the period of the carbon tax**.

       *Much of that fuel use would be for heating and power generation rather than for transport so it is not strictly comparable.  Fuel use for private vehicle transportation may have fallen more or less than that 20%.

       **Neither does the Carbon Tax, in that it was already falling before the introduction, although no doubt the carbon tax helped maintain and even accelerate that fall.   

43395. MA Rodger at 04:13 AM on 26 July 2013
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       

       dvaytw @42.

       In the quote you present it says that somebody "thinks more energy is somehow transferred to the bottom of the ocean even though it isn't really warming it because there is so much volume there." Given the subject here is the 700-2000m layer (I assume, it being the deepest discussed in the Wattsupia link), that somebody's thinking would be at least partially correct. At present there is more OHC accumulating 700-2000m than there is 0-700m. The "so much more volume there" is only about 50% more and the "more energy" has since 2005 been not far short of being 50% more. Looking at the numbers, 0-700m OHC 2005ave - 2012ave OHC = 25.3ZJ. 700-2000m 34.9ZJ putting the average temperature increase 700-2000m at 92% of the 0-700m increase.

       Of course the devilish mathematics practised by these denialist types is a good match for their devilish physics where there is "warming" which is irrelevant and proper warming which is very relevant. So it isn't impossible that the 92% is somehow the wrong sort of %.

43396. KR at 04:06 AM on 26 July 2013
       Why doesn’t the temperature rise at the same rate that CO2 increases?
       

       keitho - The oceans will not stop warming, will not magically maintain a cooler atmosphere in the presence of a GHG driven forcing imbalance. I hope you are not being disingenuous in that regard - you are, however, giving me that impression. 

       Ocean warming simply lags behind that forcing. Meaning that we will (with variations such as ENSO) continue to see atmospheric warming, and even if were to stop emissions instantly we would continue to see the oceans and atmosphere warm up until the Earth again radiates as much as it receives. It's just a long climate response time due to the high ocean thermal mass - not a 'get out of jail free' card. 

43397. Russ R. at 04:02 AM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Tom Curtis,

       Very good presentation of the data in context.  I agree with your conclusion, the exchange rate movement is a better explanation for the increase in vehicle day-trips.  

       However, I would take a bet that on top of doing more single-day trips in general, British Columbians are bringing back more gasoline per cross-border day trip, simply because thanks to the added fuel taxes, the relative price differential on gasoline will have widened even more than the differential on other importable goods.

43398. michael sweet at 03:57 AM on 26 July 2013
       Why doesn’t the temperature rise at the same rate that CO2 increases?
       

       Keitho,

       The ocean will not stop the atmosphere from warming.  If the deep ocean absorbs a lot of energy it might slow warming down a little.  If the recent slowing in the increase of surface temperatures is caused by ocean warming (as compared to just random variation), it might mean that we have an additional 10 years before 2C is exceeded.  I would point out that with current climate change we have already experienced record climate damages in the past three years worldwide.  It might be a good thing if the deep ocean gave us more time, but it is no panacea (especially if we use it as an excuse to waste another decade).

       Heat always goes anywhere that heat is absent from.  First the surface warmed, then the middle and now we are seeing the deep ocean start to warm.  The question is how fast it will go to each location.  The movements of heat are complex and that is why scientists are working to understand the heat fluxes better.  If the heat currently accumulating in the middle levels of the ocean is somehow funneled under the Antarctic ice shelves that would be a big problem, because of sea level rise.  As scientists learn more about the heat fluxes they can better estimate the chance of problems like that.  It strikes me (without data) that while heating the ocean might make the surface temperature a little lower for a while, it would be more likely to melt Antartica.  Since I live in Florida that would be bad.  Which do you prefer?

43399. Flakmeister at 03:51 AM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       Tom,

                 thx for following up on my skepticism. The exchange rate drives the cross border shopping and one can easily see that in early '09 the CAD went into the crapper (and has subsequently returned)...

43400. Michael P at 03:47 AM on 26 July 2013
       Update on BC’s Effective and Popular Carbon Tax
       

       The population of BC is approximately 4.4 million. On that basis, an additional 10% of population make day trips across the border, once a month. Assuming that every single one of those day trips includes filling the fuel tank, then we're talking one tank filling for 10% of the population. Assuming that the average person fills a tank approximately once a week, the most that the statistic could account for would be approximately 2.5% reduction in fuel usage in BC. There's still a lot of fuel reduction that cannot be explained on that basis. Now, even assuming that we only fill the tank once a month, there's still a 9% reduction that is not explained by the cross-border traffic. I would be interested to see data that shows the trend clearer, but a cursory view seems to show that the 19% reduction is not explained by filling up south of the line.

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