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Comments 48651 to 48700:

48651. curiousd at 14:43 PM on 13 February 2013
       Renewables can't provide baseload power
       

       Question....Some time ago I received comments from folks at SKS that they might post a lead article by me on CO2 offset solar charities. Months have passed and I have interacted with  many such organizations plus found some interesting facts. For instance, largely due to "The Swanson Effect" (crystalline silicon solar cells are factor 35 cheaper than ~30 years ago) what used to be a charity is now likely a business, though a small one. Great news in most respects but bad news for innovators like Solyndra or concentrating solar projects such as Desertec, perhaps.  Developing country inhabitants can power and light their homes cheaper with solar than using kerosene or going onto  the grid. Now what should I do?  I can send something written up, but to whom, and in what form, and what happens after that? 

48652. Susanne at 11:55 AM on 13 February 2013
       OA not OK part 20: SUMMARY 2/2
       

       I think I've just bumped into one of the concepts this series "skips lightly over", and I'm hoping you will kindly help me to crawl around it. The concept is buffer theory, and the reason I only think it's my obstacle is that I encountered it in this "simple description" of the ocean's importance for climate, written by an oceanographer:

       "...it is also clear that the ocean’s capacity for carbon dioxide is limited, as indicated by its increasing acidity. This is most extraordinary since the ocean has always been considered to be strongly buffered against acids and alkalis alike;"

       To me, a buffer is a space that separates two things for safety, as in "buffer zone" or a buffer in a schedule. After a bit of googling around I'm guessing in chemistry it's a process rather than a space and that buffer theory spells out how buffering mechanisms (mechanisms?) work. I also suspect it's such a fundamental concept that even a simple explanation requires a boatload of technical terminology, but I hope I'm  wrong about that.

       FYI the simple description is being written for a regular "climate column" we're doing for our local newspaper. Our readers' assumed level of knowledge is about year 8 school science 40 years ago. It's a great opportunity, but it would be very easy to scare the editor, never mind the readers.

       I'm not asking you to write to the level we're aiming for, but I'd be very grateful for an explanation that makes sense to me when I'm translating for my oceanographer. Can you help?

       Thanks for the series and for this site.

48653. vrooomie at 10:56 AM on 13 February 2013
       The Japan Meteorological Agency temperature record
       

       "Kriging" should be added to the Glossary.

48654. dana1981 at 10:52 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       StBarnabas @27 - you are correct.  If you click the "extreme flooding" link in the OP at the end of the 2nd paragraph in the Lukewarm Escalator section, that goes to a post by Rob Painting about research showing that the short-term pause in sea level rise was primarily caused by large flooding events.

       I'm not sure I understand your question about thermal expansion though.

48655. brent at 10:31 AM on 13 February 2013
       Announcing the Skeptical Science Glossary
       

       Thanks for the replies - might it be an idea to make sure everyone understands how to do this?  I've re-enabled scripts, but as I have FF delete all cookies when I close it, I'll need to re-check 'No Definitions' every time I visit.

       Moderator Response: [Sph] The delay has been added.
48656. StBarnabas at 09:05 AM on 13 February 2013
       The Japan Meteorological Agency temperature record
       

       Kevin

        

       many thanks. I'm constantly amazed by how little I know. Strange that a lot of my students think I know everything! What is possibly more strange that I have found that people who know little or almost nothing seem to think they know  almost everything, or at least sufficient to make profound judgements on areas totally outside their often minimal expertise.If only I could think of a relavent example. :-)

        

        

        

       Moderator Response: [DB] As a general note: refreshing the same browser window after submitting a comment submits a duplicate of the first comment.
48657. bratisla at 08:59 AM on 13 February 2013
       The Japan Meteorological Agency temperature record
       

       Glad to see kriging gaining ground in Earth sciences, especially since Matheron was head of a department where I work now and still was able to produce several great geostatistic ideas (several of his notes are available I think)

       Just one question : did you try kriging on HadCRU4, to see what happened ?

48658. StBarnabas at 08:49 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Dana

        

       Good post as ever. One query, my very simplistic understanding is that in La Nina years more heat is retained in the ocean cooling the surface and in La Nino years more oceanic heat is transferred to the atmosphere cooling the ocean slightly. I had understood the sealevel drop in 2010 was due to very wet weather over large continental masses shifting c 1cm of water from the ocean to the land.

        

        

        

       Of course the thermal expansion coefficient of water is temperature dependent and the mix of heat between the upper and lower ocean layers would cause an effect – I could easily do a calculation, but I suspect there are already many papers on this?

        

48659. Tom Curtis at 08:07 AM on 13 February 2013
       Sea level rise predictions are exaggerated
       

       Kevin @22, unless serious efforts to reduce carbon emissions are in place soon, the temperature difference between the end of this century and now will be approximately that between the coldest period of the Last Glacial Maximum and the Holocene average.  That temperature difference was enough to cause a 100 meter rise in sea level in 8,000 years, the equivalent of a 12.5 mm per year rise.  Given that, a rise of  0.785 meters (increase of annual rate to average rate of deglaciation over the century), or 1 meter (increase to deglaciation rate over fifty years, and constant thereafter) are likely.

       Given that the Earth warmed gradually after the LGM so the actual differential in temperature during the last deglaciation was less than what we will experience, and given that periods of much faster melting occurred durring the last deglaciation, sea level rises of 2 meters are a distinct possibility.

48660. Kevin C at 08:02 AM on 13 February 2013
       The Japan Meteorological Agency temperature record
       

       StBarnabas: I've used nearest neighbour, inverse distance and polyharmonic splines as well as kriging. The interesting thing is that, as long as you use a distance cutoff of 1000-1500km, they all give similar results to kriging. The temperature data is pretty well behaved and it doesn't much matter what you do with it. Robert Rhode in his recent BEST memo showed something similar - that the GISTEMP method (which is essentially a kernel smooth) comes close to kriging.

       The principle benefit of kriging in this case is that you don't need to set a distance cutoff - you get a global map which naturally reverts towards the global mean if you get too far away from an observation.

       In general kriging has some awesome properties. For example it gives you a proper area weighted mean almost by magic, and weights neighbours of a cell according to how much distinct information they add. Unlike BEST I'm losing some of the benefits by starting from the gridded data, but again for this problem it doesn't make much difference.

48661. Tom Curtis at 07:48 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Nick Palmer @ 23, the most germaine point is that luke warmers will insist that most of the rise in temperature from the depth of the LIA until about 1940 is natural in origen.  That, is also, the concensus position.  However, it means that the "lukewarmer" prediction for temperature increase above MWP conditions given only a doubling of CO2 is from 0.7 C assuming natural conditions return to those at the lowest point of the LIA, to 1.8 C above MWP (assuming they stay at current levels).

       Of course, on current trends we will significantly more than double atmospheric CO2.

48662. StBarnabas at 07:47 AM on 13 February 2013
       The Japan Meteorological Agency temperature record
       

       Kevin

       thanks. Kriging looks a very interesting technique, I would be tempted to use a cubic spline or other signal processing technique. Might be an interesting comparison. With the absencence of Arctic data it is interesting that it gives such good results as I'm sure a spline or similar technique would underestimate the Arctic trend.

48663. Kevin C at 07:16 AM on 13 February 2013
       The Japan Meteorological Agency temperature record
       

       Composer: The Arctic is a big issue because of the magnitude of the trend there. Here's a GISTEMP figure from U-Columbia (which I've used before).

       

       The Arctic trend look like around 1C/decade - that's around 6 times the rest of the planet! So yes, leaving it out is a huge deal. And when does the trend really take off? You guessed it - around 1998.

       The rest of the missing regions are mostly land, which is in turn warming faster than ocean.

48664. Bob Loblaw at 06:44 AM on 13 February 2013
       Sea level rise predictions are exaggerated
       

       Kevin @22:

       Um, you did look at figure 2, that shows the rate of change increasing? Tamino's blog also has a recent post discussing some of this. And you realize how the rate of increase is going to depend on both warming of the oceans and increased loss of land ice, and future predictions of this don't depend on the past trend alone?

       First, you ignore the fact that the rate of increase has gone up over the last hundred years, then you do a linear extrapolation, then you admit that a linear extrapolation is not appropriate, but then you claim that the principle is the same and go ahead and do it anyway, because "the math is simpler"????

       Bottom line: you don't see any evidence because you're working so hard not to see it.

48665. dana1981 at 06:20 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Jeffrey @20 - we've got a post looking at future climate change under various sensitivity and emissions scenarios tomorrow.  It's going to be a good one, stay tuned.

48666. Rob Honeycutt at 05:37 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Nick...  Yup.  And I believe this is the original source of the colored and doctored version:

       http://www.co2science.org/education/reports/prudentpath/ch1.php

       You can catch these pretty easily when they pop up because most of the Idso's MWP Project graphs are doctored in various ways.  The always add in their own notations of where MWP, LIA, etc occur.  They delete any aspect of the original that might be inconvenient and then they add the notation "Adapted from..."

48667. Kevin8233 at 05:27 AM on 13 February 2013
       Sea level rise predictions are exaggerated
       

       So, you have a prediction for sea level rise of between 750mm and 2,000mm, but have observed rates of 3.2 mm/yr.  100 yrs X 3.2 mm/yr = 320 mm.  So, essentially, you are predicting a substantial increase in the rate of rise.Looking at the graph of sea level rise for years 1880-2000,there does not seem to be much chance of your prediction coming true. 

       A gradual, steady increase from 3.2 to 11.8 mm/yr by 2100 would give you an increase of 750 mm after 100 years, but it would take a steady increase to 36.8 mm/yr by 2100 to give you a 2 M rise.  I realize you are not advocating for a linear increase, but the math is simpler and the principle remains the same.

        

       Bottom line, I don't see any evidence that these increases are occurring, so I don't see the predictions happenning.

48668. Nick Palmer at 05:21 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Rob Honeycutt@19

       Yup it does come from a denialist source.That is why I think it can be used against lukewarmers - Judo uses the enemy's strength against himself - to make the argument powerfully that even 1°C of warming is likely to have far reaching effects.

       Connolley put in the data that was sneakily missed out - see below

       

48669. Rob Painting at 04:49 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Nick Palmer - maybe the lukewarmers can explain why global sea level (a proxy for the volume of global land-based ice and therefore global temperature) during the Medieval Period was static during that time and only began to rise appreciably in the 19th century?

48670. SEAN O at 04:34 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       This graph also shows up at Stoat:

       http://scienceblogs.com/stoat/2013/02/07/the-sleepwalkers/

       WMC comments:

       "So now we know how MR proposes to support his assertions: provide evidence that doesn’t cover the period in question, and erase information that contradicts his assertions – even when that comes from the very refs he is quoting"

       http://www.flickr.com/photos/belette/8454321768/

48671. Jeffrey Davis at 03:09 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       It needs to be stressed that climate sensitivity is not a limit on warming. A climate sensitivitiy of 2C does not mean that there will only be 2C of warming. Warming will continue as more CO2 is added to the atmosphere. Nor is there any guarantee that we won't face a terrible catastrophe before warming reaches 2C. Storm damage, crop damage, the advance of insect pests have all reached terrible levels today when we've only experienced around .9C of warming.

       Ask a "luke-warmer" if they'd play Russian Roulette with 3 live bullets out of 6.

48672. Rob Honeycutt at 02:47 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Nick Palmer...  First thing I notice about that graph, even without going to Stoat to see it, is the phrase "Adapted from Ljundquist, 2010."  I would bet my bottom dollar that graph actually comes from the Idso's website, CO2science.

48673. Composer99 at 02:40 AM on 13 February 2013
       The Japan Meteorological Agency temperature record
       

       What a difference in trend the missing 15% of coverage makes.

       I guess it shouldn't be surprising given that the missing areas are among the fastest-warming.

48674. Tristan at 02:26 AM on 13 February 2013
       The Japan Meteorological Agency temperature record
       

       If you keep putting together such articles I'm going to get embarrassed by the amount of compliments I give you.

48675. Nick Palmer at 00:16 AM on 13 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       

        

       Perhaps this is too simplistic but, from the graph aboove, which was taken from Stoat's post "The Sleepwalkers", from the height of the MWP to the depths of the LIA seems to only be about 0.9°C which is what a lot of the lukewarmers expect we are going to get, with their favoured low sensitivity figure.

       But, eyeballing, that would put us about 0.7°C on top of the peak of the MWP which suggests that such an apparently small increase (which the lukewarmer types represent as insignificant) would actually be quite a big deal in terms of the changes to the planet, no? From the LIA to the MWP was certainly a big change to the climate in the northern hemisphere…

       Do they shoot themselves in the foot by backing an approximately 1 °C rise figure? If they have already accepted up to 3°C sensitivity, as Moshers and co's self-description seems to suggest, then surely it is an open and shut case for them to agree that any rise between 1-3°C has got to be extremely risky?

48676. Martin Lack at 23:22 PM on 12 February 2013
       A Brief Note on the Latest Release of Draft IPCC Documents
       

       Given that their own belief sytem is almost entirely based on non-peer-reviewed material, it is ludicrous for climate contrarians to complain about the IPCC reviewing "gray literature".

48677. shoyemore at 18:57 PM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Andy Skuce @6

       You will find Steve Mosher's definition of Lukewarmerism in the comments to this post - reasonably early on.

       http://wattsupwiththat.com/2013/02/01/encouraging-admission-of-lower-climate-sensitivity-by-a-hockey-team-scientist/#comment-1214225

       I am still at a loss to define "Lukewarmers" - there seems to be agreement on teh fundamentals of the science, but a difference in the response. Some, like Richard Tol and Pielke Jnr, just seem to take a different tone - Tol for example is on the "academic board" of the science-denying Global Warming Policy Foundation, but supports a carbon price for all the right reasons. Others (Judith Curry) desire to be "bridge builders", but turn out to be anything but. My own suspicion is that they just get a kick out of running with the foxes and hunting with the hounds at the same time.

48678. Doug Bostrom at 16:17 PM on 12 February 2013
       Announcing the Skeptical Science Glossary
       

       Brent (and others wishing not to have glossary popups appearing), you can pull up the tab at bottom of your screen ("Look up a Term") and select "No Definitions" (at lower right). 

48679. brent at 12:06 PM on 12 February 2013
       Announcing the Skeptical Science Glossary
       

       Excellent idea in principle but with FF 18.0.2 it's infuriating, forever trying to avoid keywords with my cursor.  Afraid I'm going to disable scripts for SkS from now on.

       Moderator Response: [Sph] As Doug points out in the following comment, you can easily turn off the automated glossary function using the glossary tab at the bottom of the page.
       
       We are looking into adding a short (configurable) delay, but the coding for it is not straightforward.
48680. dhogaza at 12:02 PM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       In the case of Mosher and Fuller, I wonder if the need to distance themselves from the consensus view despite their actually sharing the consensus view is related to the fact that they wrote and profited from a book that accused leading climate scientists of scientific fraud?

       It was Mosher who, years ago, before ClimateGate, coined the term Michael "Piltdown" Mann as part of the CA-led attack on MBH 1998/99 and the "hockey stick", in essence claiming that his work on climate reconstructions was a fraud on the level of Piltdown Man.

       Perhaps portraying the mainstream as having moved to their view, rather than the obvious fact that their view has moved to be in line with the mainstream (regarding climate sensitivity to a doubling of CO2, at least) is easier than admitting that their earlier claims of scientific fraud were unwarranted.

        

48681. dhogaza at 10:51 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Interesting reading over at fuller's.   Self-congratulation on scientists like Annan accepting the lukewarmer position that climate sensitivity is ... about 3C.

        

       The delusion over there seems real.  They really seem to believe that the consensus position has been 4C or more, and all of the calls for action are based on sensitivity at that level.

        

       While sensitivity in the "about 3C" range, even if a bit lower as Model E and other results might suggest, has been, of course, the basis for policy arguments that we must take definite action if we want to restrict warming by 2100 to 2C over preindustrial levels.

        

       The disconnect with reality, history of climate science, history of the political calls for action is just ... stunning.

48682. JasonB at 09:36 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       dorlormin,

       That's exactly right. Someone who derives their conclusions from the evidence can't help but arrive at the obvious value:

       

       There is still uncertainty, sure — for example, the sensitivity is probably temperature-dependent since certain feedbacks only exist within certain temperature ranges (e.g. in terms of albedo, highly-reflective ice can only exist up to a certain temperature; vegetation can only exist up to a certain temperature, etc.) which means the past values may not be exactly the same as the future, but that's still the best information we have, and saying "Well, it was high in the past, but we're now pushing it into a regime unknown for tens of millions of years and we don't know what it will be under those circumstances, so let's assume it's lower!" doesn't seem like good risk management!

       Choosing to ignore that and instead assume a sensitivity a-priori (or using a technique that is fundamentally unable to give you an accurate answer while ignoring those that do) is not scientific, no matter how "scientific" the proponents feel they are because they have grudgingly agreed to accept every other piece of evidence leading up to that last one, which is just one step too far for them. It's as if they think this last obstacle to action is impenetrable, so they're willing to concede everything else, but you get the feeling that if you push too hard on the last one they'll take a step backwards and proclaim "But CO₂ is a trace gas anyway! UHI! Sun!". :-)

48683. dorlomin at 08:52 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Lukewarmism is a nonesense idea that is designed to artificially polarise the debate into discrete camps. It is a premeditated selection of the minimum defensible sensitivity and creating an argument around that rather than an open process of bringing evidence to the table. 

48684. dana1981 at 08:45 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Tom @10 - I entirely agree.  Mosher's move towards the IPCC/consensus has been quite noticeable, and as a result he's become less and less popular amongst the contrarians.  It does seem like he's holding onto this 'lukewarmer' label just to distinguish himself rom the consensus position somehow.

       I also very much agree that if you believe there's a ~50% chance equilibrium sensitivity is 3°C or higher, you should be pushing hard for urgent action on climate change.

       And that dovetails very well with my next post coming up on Wednesday, looking at future climate change in various sensitivity and emissions scenarios.  Stay tuned, that's going to be a good one.

48685. dhogaza at 07:51 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       " But though he has shifted towards the IPCC position, he does not want to give up that title, so he has expanded the range of "lukewamer" positions to the right. "

       
       

       And consider this:

       
       

       "Everything we believe is well within the consensus and we think that you can change the consensus from inside the tent "

        

       If one's opinion lies within the consensus, the need for changing the consensus is driven by ... what, exactly?

        

       Tom Fuller has also in the past said he thinks sensitivity is about 2.5, i.e. dead-on with NASA GISS Model E's 2.4-2.7 range.  He's made a big deal of James Annan's work to diminish the high tail of uncertainty as though this is somehow counter to the mainstream view (Annan thinks sensitivity lies within 2.5-3C, though he agrees that higher values can't be entirely ruled out).

        

       I think that lukewarmerism is just obfsucation - claiming a difference where non exists in order to appear to accept the science in order to support their political position that nothing need be done (or not much needs to be done).

        

       I think it's just an effort to paint the mainstream view as being that sensitivity is > 3C and likely considerably higher, that calls for action are based on that view, and then "reasonably" extrapolating that accepting a lower value (say 2.5-3) means no immediate action need be taken ...

        

       
       

48686. Tom Curtis at 07:46 AM on 12 February 2013
       Humidity is falling
       

       Jeff313 @7, thankyou for admiting that your formula was merely sloganeering, not analysis.  Once, however, you admit that the effect depends on the values, unless you analyse the actual values and the effect they have, which you have not done, you are unable to say anything regarding the net effect.  This is particularly the case given that increases water vapour provides both a positive (the WV feedback) and negative (the lapse rate feedback) feedbacks.  If WV is increased at medium altitudes, but decreased at high altitudes, that can have the effect of neutralizing the lapse rate feedback, while strengthening the water vapour feedback.  Ergo, your slogan is not valid even as a "general statement".

48687. Tom Curtis at 07:16 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       dana @9, I think that has more to do with the fact that Mosher has been shifting towards the IPCC position over time.  I doubt many of his "fellow" lukewarmers would still recognize him as one.  But though he has shifted towards the IPCC position, he does not want to give up that title, so he has expanded the range of "lukewamer" positions to the right.  Indeed, he has expanded it so far that his estimate of the probability of a climate sensitivity between 3 and 4.5 C is likely greater than the IPCCs. His estimate of for greater than 4.5 C is, however, much lower.

       In fact, I think his high estimate for 3-4.5 C is the real story here.  The disaterous future consequent on greenhouse emissions that is currently predicted assumes a climate sensitivity of 3 C per doubling of CO2.  Mosher things there is nearly a 50/50 chance it is worse than that.  Why, then, is he not demanding urgent action to mitigate climate change?

        

       Andy Skuce - Mosher's comment.

48688. Tom Curtis at 06:52 AM on 12 February 2013
       Temp record is unreliable
       

       Kevin @266, first, the chart I showed @263 is not of adjustment of individual temperature datums, but of adjustment to station trends.  That is not a matter of adjustments down early and up late, but of differing adjustment for each station that just happen to have a mean value slightly above zero, even though nearly half make negative adjustments to the trend.

       Second, it is not a 10% adjustment, but an 8.9% adjsutment in a record with an 11% error margin.  Further, it was not an adjustment in the temperature at all, but an adjustment in an index of temperature which you have done nothing to show makes that index less accurate.  For all you know, and most probably, it has made it more accurate.

48689. dana1981 at 06:52 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Pierre-Normand @8 - right you are, thanks.  Figure caption updated accordingly.

       Tom @7 - I still think that's a pretty minimal difference between the IPCC and Mosher positions.

48690. Pierre-Normand at 06:41 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Although it's been released in Jan 2013, the University of Colorado mean sea level data seems only to extend until late 2012. The last data point is for 2012.8590 (That is 859/1000 of the year, or something like the 313th day of 2012).

48691. scaddenp at 06:39 AM on 12 February 2013
       Temp record is unreliable
       

       Kevin, I am giving you reasons why a disparity would suddenly appear. A change in TOBS, move from city to airport, change of thermometer, and change of screen will all create a discontinuity in the record that the algorithm will pick up, and they will all result in temperatures taken after the change being lower than the ones before, so adjustments will increase trend.

48692. Tom Curtis at 06:37 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       shoyemore @1, it is interesting to compare the IPCC AR4 with Mosher's definition:

       "Analysis of models together with constraints from observations suggest that the equilibrium climate sensitivity is likely to be in the range 2°C to 4.5°C, with a best estimate value of about 3°C. It is very unlikely to be less than 1.5°C. Values substantially higher than 4.5°C cannot be excluded, but agreement with observations is not as good for those values. Probability density functions derived from different information and approaches generally tend to have a long tail towards high values exceeding 4.5°C. Analysis of climate and forcing evolution over previous centuries and model ensemble studies do not rule out climate sensitivity being as high as 6°C or more. "

       (Original emphasis)

       In the contrained language of the IPCC, that means that thre is a less than 10% chance that the Climate Sensitivity is less than 1.5 C per doubling of CO2.  There is a 66% chance it lies between 2 and 4.5 C per doubling, and that the probability does not fall of as quickly above 4.5 C as it does below 2 C.

       The IPCC did not publish a PDF for its own assessment, but the right skew of probabilities means that a climate sensitivity between 3 and 4.5 C is more probable, on their assessment than a probabiltiy between 2 and 3 C..  That is, although 3 C is the modal value, the median and mean values probably lie between 3 and 4.5 C.

       Because Mosher has not used the same demarcations, and because his assignment of probabilities is inconsistent, with a total probability greater than 1.025, direct comparison is difficult.  It is clear that somebody accepting IPCC values would preffer the upper half of the bet between the climate sensitivity being between 2 and 3 C, or 3 and 4.5 C,   As the probability of greater than 4.5 C is greater than the probability less than 2 C, and hence greater than the probability of between 1 and 2 C, they would also take the upper half of Mosher's proffered bet.  Hence I disagree with both Dikran and Dana that Mosher's opinion that the IPCC just about fall within the opinion of luke-warmer.

       Having said that, I finde Mosher's definition of "lukewarmer" strange.  It is strange both because most self avowed lukewarmers I have known have been quite clear that:

       1) The probable CS is around 1.5 C per doubling (very close to Mosher's lower limit); and

       2) The climate sensitivity is sufficiently low that no major action need be taken to mitigate climate change.

       Indeed, "lukewarmer" seems to be a badge for saying, "I'm not so foolish as to deny well established physics, but let's do nothing to protect the future".  I should note that both Lindzen and Monckton who purport to believe the most probable cliimate sensitivity is 0.5 C per doubling also claim to be "lukewarmers".

48693. Andy Skuce at 06:32 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       shoyemore:

       Do you have a link for that?

       Just like M Jourdain in the play le Bourgeois Gentilhomme who was surprised to hear he had been speaking prose all his life and never knew it, so it is that I am now shocked to discover that I have been a lukewarmer all along, at least by Steve Mosher's definition. 

       The 50% of Lukewarmers who would vote for a most likely climate sensitivity between 1 and 3 is a broad church encompassing contrarian extremists like Ridley, as well as the IPCC consensus. There's a factor of three over that particular range—a lot of uncertainty by any but Judith Curry's standards—and it implies a huge difference in climate outcomes from mild to very serious.

       I think that what truly unites Lukewarmers is not any internal consistency of scientific opinion, but rather their desire not to be seen as so stupid to deny basic science and, at the same time, not being able to admit that the dirty hippies were right all along.

48694. pmauca at 05:49 AM on 12 February 2013
       Announcing the Skeptical Science Glossary
       

       Great idea, but lots of irratating popups in firefox!

48695. dana1981 at 05:47 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       In fact, rather than "lukewarmer", I'd characterize Mosher's position as "pretty darn warmer".

48696. dana1981 at 05:45 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Agreed with Dikran @2 - Mosher's definition of "lukewarmer" is pretty much where the IPCC already is, and close to where I am too.  Basically he says lukewarmers think the most likely equilibrium climate sensitivity value is maybe a smidge lower than the IPCC does.  That's an inconsequential distinction, and incompatible with the positions of Ridley and Michaels.

       HH @3 - yes, let's just hope that Ridley doesn't exert any significant influence over UK climate or energy policy from his new position.

48697. A Change in the Weather at 05:45 AM on 12 February 2013
       An Updated Look at What Keystone XL and Alberta Tar Sands Mean for the Climate
       

       The oil from the tar sands, like any oil found anywhere, will not "replace" any other oil. It will be additive. It's a circular dynamic. The supply/demand curve determines the price, and any oil that can come on at that price will come on. As long as there's expansion of fossil-fueled infrastructure in the world, demand will be there.

       This is exactly what's happening with natural gas. Notionally, it should replace coal for electric generation in the US. And it is. But the displaced coal is being exported to China.

       We can't solve the carbon accumulation problem by adding more carbon. Once we enter the detailed discussion of the relative merits of carbon-emitting projects, we are lost. We have implicitly accepted the carbon emissions. We're at the point of choosing the moment to start reversing this modality.

       
       I agree the deniers are a danger. They will be incensed. Violence at some point is not hard to imagine. But violence is also the endpoint of continuing down our current path, as the atmosphere becomes more unstable and agriculture fails.

       Obama would be wise to avoid mentioning KXL until he has an entire strategy: no KXL, but yes to this (e.g., a Manhattan Project for renewables deployment). But that needs to happen very soon.

48698. Hyperactive Hydrologist at 05:29 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       Ridley has recently been elected to the House of Lords and he is also on the GWPF’s Academic Advisory Council. 

48699. SteveFunk at 05:28 AM on 12 February 2013
       Announcing the Skeptical Science Glossary
       

       Here's a minor glitch:  The definition of source does not fit the context, i.e. sources of information.

48700. Dikran Marsupial at 04:47 AM on 12 February 2013
       Lukewarmerism, a.k.a. Ignoring Inconvenient Evidence
       

       @shoyemore Seems to me the IPCC fall just about within that definition of "lukewarmer"!

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