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Comments 73301 to 73350:

73301. JosHagelaars at 22:02 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       @Peter Hogarth "..problem is it's man-hour and computationally intensive to work through this.." Maybe you could use volunteer computing to help you with that. Ref: http://boinc.berkeley.edu/.
73302. Norman at 22:02 PM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       muoncounter @ 143 "To question the experts, without the intent of disproving them? And yet you don't seem to search for understanding the expert opinions; instead, as here, you imply that Jeff Masters is wrong because Bastardi and Watts don't say the same thing." I am not implying he is wrong, I was just making the distinction between an expert opinion and a scientific study. Here is what you posted by Jeff Masters "the wild roller-coaster ride of incredible weather events during 2010, in my mind, makes that year the planet's most extraordinary year for extreme weather since reliable global upper-air data began in the late 1940s. Never in my 30 years as a meteorologist have I witnessed a year like 2010--the astonishing number of weather disasters and unprecedented wild swings in Earth's atmospheric circulation were like nothing I've seen." He states this without graphs or trend analysis so it is his opinion (expert) and the two other Bastardi and Watts do see the same data (which I do not see on a daily basis and could not offer an opion at all on the matter) but do not form his opinon. I was not saying he is wrong I was just wondering why the others do not see this if it is this obvious. Also I am researching to understand Masters opinion on the matter by looking into historical extremes of the past to see if he is correct with his opinion.
73303. pauls at 22:02 PM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       Chris G - The basis of the statement was uncovered in the comments of the 'Pielke Sr. Agrees' post. His calculation is unrelated to feedbacks. RealClimate put up an article about it at the time: 'Recently, Roger Pielke Sr. came up with a (rather improbably precise) value of 26.5% for the CO2 contribution. This was predicated on the enhanced methane forcing mentioned above (though he didn’t remove the ozone effect, which was inconsistent), an unjustified downgrading of the CO2 forcing (from 1.4 to 1.1 W/m2), the addition of an estimated albedo change from remote sensing (but there is no way to assess whether that was either already included (due to aerosol effects), or is a feedback rather than a forcing). A more appropriate re-calculation would give numbers more like those discussed above (i.e. around 30 to 40%).'
73304. damorbel at 21:54 PM on 2 October 2011
       The 2nd law of thermodynamics and the greenhouse effect
       Re your Moderator Response: [Dikran Marsupial] to #283 "I pointed out that the distinction was (i) irrelevant to the discussion of whether heat flow is bidirectional or not (which depends only on their temperature) " You appear to want me to accept that heat flow can be "bidirectional" in some way. As far as physics is concerned I think this is where we disagree. Heating (or cooling) results in an increase (decrease) in temperature difference between two locations, a given location can only have one temperature so it is quite impossible for one location to have, simultaneously, a rising and a falling temperature. If the energy entering this location is balanced by the energy leaving it, as for example in the atmosphere, the temperature of the atmosphere will not change due to changes in GHG concentration, since GHGs both absorb and emits radiation at a given temperature, nothing will be changed if the amount of CO2 is increased (or decreased). Put another way, if there was no CO2 at all the radiation from the surface would replace that from the atmospheric gases, there would no radiative temperature change. Of course the surface is warmer than the upper atmosphere but that is due to gravitation, not radiation. Further you wrote:- (ii) it is irrelevant to the greenhouse effect because as far as the atmosphere is concerned it is heated from below by IR radiated from the surface, not from the Sun above" Have we not already agreed that the Earth doesn't have a significant heat source inside it? I agree that, if the Earth had a heat source inside it, big enough for, let us say 240W/m^2, then its would be closely related to the concentration of GHGs (and the emissivity of the surface). Further, as things stand, the Earth's average temperature would be what it is now, except it would be uniform (no frozen poles!) In my physics this planet, with its internal 240W/m^2, has a temperature that is very dependent on it emissivity. To explain, if it was a metal planet its surface temperature would be very high, highest of all if it was gold plated (gold has the lowest emissivity of all common metals). However if this (gold plated?) planet would have a GHG atmosphere its temperature would be lowered, the amount it was lowered would depend very much on the mass of the GHGs. But do not be surprised that such a planet (with no star nearby) would have a uniform surface temperature.
       Moderator Response: [Dikran Marsupial] Your misunderstanding is right at the most basic level, so it would be a good idea to reach an understanding of heat flow before trying to apply it to the Earth.

       Do you agree that any body at a temperature above zero degrees Kelvin will radiate photons of energy? Please confine yourself to a direct answer to the question, rather than digress (which will prevent the discussion from making any progress).

       Damorbel please demonstrate that you are not just trolling and are willing to address the science by giving a direct answer to the above question, without digression. Your disruptive behaviour on these threads has led to the point where you need to demonstrate that you are able to learn and are not here simply to disrupt the discussion.

       Please can everyone else refrain from responding to damorbel until I have gone through the basics with him step by step.
73305. Norman at 21:51 PM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       muoncounter @ 143 With keeping with the OP: "'Why are scientists predicting that global warming will cause intensifying and/or increasing extreme weather events?'" That is the question posed in the article above. I would not disagree that the drought in Texas or Lousiania is extreme (well outside the normal). Nor severe tornadoes in 2011. Nor even that 2010 and 2011 had extreme weather events occur. Yes they did have extreme weather events. But I still stand by the fact that your graph of Texas and the tornado graph above both show that the trend in extreme weather is decreasing and that is the topic. The topic was not if 2011 had extreme weather events or not but if the trend for extreme weather events is increasing.
73306. barry1487 at 21:36 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       The link to SKS post 'Ocean Heat Content And The Importance Of The Deep Ocean' in the article brings up a 404 error when I click it. I have been curious about our lack of knowledge re vertical mixing. Would this not have a bearing on the response time of the oceans to atmospheric warming? Why are we so confident that the oceanic lag to equilibrium sensitivity is 30 - 40 years? Do we somehow have a grasp on mixing rates despite knowing little about the actual mechanics? Having learned that the global average temperature at the surface of the oceans is warmer than the average temperature of the near-surface atmosphere, and knowing about the thermocline, it is a puzzle as to how the atmosphere warms the oceans and not the other way around, or what it means that a warming atmosphere is till cooler than the surface of the oceans. My guess is that the averaged temperature difference is sort of a constant, and that if one strata warms or cools, then so does the other, with waves, wind and currents, and response to diurnal and seasonal changes mixing things up at the boundary. But I've found no explanation for this line of enquiry on my travels. Scant knowledge on the actual mechanisms drawing heat energy into the deeps makes it a tough nut to crack for this layman. I've found plenty of material on horizontal heat transport across the oceans, but little on the physical details of vertical mixing. Any suggestions greatly appreciated.
73307. Peter Hogarth at 20:10 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Rob, really interesting article, the vertical mixing is the factor we don't understand well, at the moment NOAA has years worth of full water column sonar data, which can help allow us to visualise the deep sea currents and layers, problem is it's man-hour and computationally intensive to work through this, effectively 3-D high resolution data. Daniel Bailey at 13:12 PM on 2 October, 2011 Beautiful. Thanks for pointing us to this.
       Response:

       [DB] An interesting Science Daily article on meso-scale eddy processes here.  A PDF of the study forming the source of the article is located here.

73308. Dave123 at 20:07 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Rob@11- I understand that the OHC hiatus isn't a model. It's the cause I'm interested in. Look, "we" assert that modeling is useful because it is based on physics (and chemistry) and not statistics. Models I built never had to detail fluid mechanics as part of the mass transfer- we had uniform turbulent flow at all scaleings. Ocean flows are largely laminar- low Reynolds number except at coast-lines where waves are turbulent. From a naive point of view a layered ocean might stay that way, the surface becoming hotter, increasingly less dense and therefor more stable on top of a denser colder base. No mixing invited. You can see that I think in certain really saline ponds with fresh water overlays. But less dense doesn't quite work that way- as the surface becomes less dense, that relieves pressure on lower layers and they can well up. Thus a top bottom current loop can be established. Do I undertand correctly that the millenial exchange between deep ocean and surface water is based on that mechanism? Now are we talking about accelerating the global currents? Regional acceleration? New currents developing? Or is there another mechanism that I'm unaware of? Do Hurricanes cause turnover? Dan@7- thanks for sharing that! Some of the circulation patterns reminded me of Jupiter. Rob@11- Re TOA- when this question came up I thought that TOA energy balance was a direct satellite measurement. So I went looking for verification and couldn't validate that notion. It seems that the TOA number is an argument between satellite data and other measurements. I probably missed something. There are some annoying consequences to this... but I'll hope you'll show me the error of my background studies before I bring them up.
73309. Rob Painting at 18:46 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Dave123 @ 5 - see the hiatus decades in the observational record of OHC highlighted in figure 1 - that's not a model output. I have another post on Meehl (2011), detailing the mechanisms at work in the model runs. Looking at the ocean in horizontal layers, misses the important changes taking place in the vertical plane. It'll be clearer in the post - there's a few graphics from the study detailing this. Utahn @ 8 - there are a number of references throughout the post pointing out it is a model-based study. Good point about linking to related SkS posts - forgot to do that.
73310. Rob Painting at 18:32 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Muoncounter @ 3 - the issue is: why is there short-term natural variability? Take it as given the authors of this study understand there is a long-term warming trend. Choose different start/end points for the decades (in your graph), and see what happens. The late 1950's to late 1960's appears to be a hiatus decade for instance. Is that clearer? Icarus @ 4 - Meehl (2011) refers to Hansen (2005) and Trenberth, Fasullo & Kiehl (2009). As for the top-of-the-atmosphere (TOA) energy imbalance, there are upcoming posts on this issue - it's not cut and dried. I think it boils down to this: was the slowdown due to natural variability alone?, or did other factors (aerosols) play a role too? "Is it reasonable to take the increasing global sea level over the last decade as confirmation that there has been no slowdown in increasing total energy content? That's a very good question, but again, it's not so simple. If, for example, ice melt from ice caps and glaciers accelerate (it has), then that can become the dominant contributor to sea level rise, and mask the slowdown in OHC. And yes, I have an upcoming post on closing the sea level budget too. You might want to take a look at Ari Jokimaki's SkS post: Deep ocean warming solves the sea level puzzle
73311. Glenn Tamblyn at 18:08 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Craig Allen @6 I suspect that the ocean circulation component of the climate models is one of the hard aspects. Modelling fluid flows in the short term to determine energy transports while also getting longer term fluctuations in the flows - volumes but far more importantly, 3D distribution is always going to be hard. You might get the short term stuff right but not pick up the longer term oscillations as well. Or vice versa. So modelling climate variabilty which is the oceans dog wagging the surface temp tail is always going to be hard. Thats why reading too much into surface trends without looking at the total system changes is a bit pointless.
73312. Utahn at 14:20 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Great summary, some of the text is a bit confusing (as is the title), in that it makes it look like they did measurements, rather than model runs. I do believe this is very likely occurring, but it could be more clear that this is a modeled result. It might also be nice to have a post or addendum on other pieces of evidence of deep ocean heating (actual measurements, sea level, etc...)...or link to another sksci article...
73313. Chris G at 13:34 PM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       Old Mole, That is the rub, you can claim that the increase in CO2 is only a quarter of the forcing, and you might be technically correct (or at least in the right ballpark for driving forcing), but your estimate would suffer an error of omission by not acknowledging the feedback forcings that come with any increase in energy content (temperature). It is almost like an accounting game where you show that CO2 has less effect by comparing it to the total effect which includes water vapor, but you don't give CO2 credit for causing the increase in water vapor. I suspect Pielke is avoiding the feedbacks that CO2 is responsible for because he cites work that he published in 2008 that did not find an increase over North America and makes no mention, nor sites the work that Trenberth did earlier, in 2005, which did. Both authors acknowledge that the data is (was?) problematic, but if you post a quote that says, "‘there are no sufficient data sets on hand with a long enough period of record from any source to make a conclusive scientific statement about global water vapor trends’." (attributed to Vonder Haar), why turn around and cite anything at all, unless you really want to believe that there is little water vapor feedback. Meanwhile, there is no reason to believe that warmer air and water does not lead to more water vapor in the air. Kind of speculating here on Pielke's rationale; anyone have more solid information?
73314. Daniel Bailey at 13:12 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Some nice visuals on ocean currents from JPL: [Source]
73315. muoncounter at 12:33 PM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       Norman#141/142: "My efforts on SkS are not to disprove ... maybe too many just accept an expert opinion without doing active research on their own to question it." To question the experts, without the intent of disproving them? And yet you don't seem to search for understanding the expert opinions; instead, as here, you imply that Jeff Masters is wrong because Bastardi and Watts don't say the same thing. "Texas precipitation graph in post 126 does show some improvement." The entire point of the 3 graphs in that comment was to show that this year is extreme - something you have disputed repeatedly in spite of the obvious evidence. Even Louisiana, with all the flooding due to spring runoff from the midwest, is 30% below its long term mean. That point alone is the very definition of the extreme conditions described in this post. Oh, your tornado graph misses the 80 EF3-5 tornadoes through just mid September of this year. That will make 2011 the 2nd highest (after 1974). Pretty extreme year, no?
73316. Craig Allen at 12:07 PM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       This raises a question I've long wondered about - how well do climate models simulate ocean circulation?
73317. Dave123 at 10:22 AM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Did I post this- or did it get deleted? - I would find this more compelling if there was data, not just model output - Do the models invoke some mechanism for the heat transfer into the deep ocean? Do you know which one(s) is activated and does it provide any guidance toward a quick study to validate mechanism and predicted temperatures?
73318. Daniel Bailey at 10:21 AM on 2 October 2011
       Back from the Dead: Lost Open Mind Posts
       Added the following 9 posts from January 2007: Jan 9, 2007 Ice Ages Jan 11, 2007 The Latest from GISS Jan 12, 2007 Red White & Blue (noise, that is) Jan 15, 2007 Calling All Science Teachers Jan 16, 2007 On the Edge Jan 17, 2007 This Blog is Different Jan 18, 2007 Ocean Heat Content Jan 18, 2007 Time to get interesting … or boring, depending on your perspective Jan 20, 2007 Leafy CO2
73319. Old Mole at 10:14 AM on 2 October 2011
       Understanding climate denial
       John Hartz @127 As our Commonwealth colleagues will be happy to remind you, we in the US tend to be a little slow on the uptake in terms of genuine threats to Western civilization: two instances last century come immediately to mind. AGW denial is only our old bad habit of isolationism wearing another mask.
73320. logicman at 10:14 AM on 2 October 2011
       Climate Change Could be Expensive for Canada
       Jonathon@15 "...Discussing only the negatives, without acknowledging the positives is akin to a corporation reporting revenues only, and omitting costs." Which they do when the costs are completely external. When gas was made from coal, the gasworks polluted the ground beneath to a significant depth. The cost of cleaning up the toxins does not appear in the historic financial records. There are many ways of damaging the environment which are not illegal, which means that many external environmental costs are not accounted for in company ledgers.
73321. Norman at 10:01 AM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       muoncounter @ 138 "Has anyone seen a credible paper saying that conditions are getting milder?" Maybe not a paper but you Texas precipitation graph in post 126 does show some improvement. Before 2011 there is a clear signal of less drought conditions after 1960. You can see many more severe dry years before 1960 than after so that would be one example to attach to a paper on the subject is someone where to write one. Extreme tornado count is down which would be good news for homeowner's.
73322. Norman at 09:50 AM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       DB @ 134 "By all means, acquire those methodologies, do the work and disprove what the current experts in the field are saying. You will be welcome to submit the work here as a guest post if it meets publication standards." I think regardless of work I would do on the topic it will not be accepted in journals. Here is why. My credentials. I have a BA in Chemistry. Long ago I did take one year in Meterology (I did receive an A). There are many people with degrees in Meterology or Climatology that want to get their research published. I cannot forsee any publication opening up their limited space to anyone with a science degree while they have so many applications from those with credentials in the field of study. Therefore I would conclude I would never be able to post such an research project. But I do thank you for the offer. The nature of my posts may seem to lack a consistent overall methodology. Mostly because I am responding to specific points brought up in someone's post. At times it does lead to divergence from the OP. My efforts on SkS are not to disprove the expert opinions or findings. (some may feel that is my goal). I am of the opinion that maybe too many just accept an expert opinion without doing active research on their own to question it. I am just working to keep the thought process active, think for yourself, question everything. Maybe it does not come across in that fashion.
73323. Norman at 09:41 AM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       Eric (skeptic) @ 136 Thanks for the link to heat related deaths. That was counter intuitive.
73324. Icarus at 08:51 AM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Thanks Rob, very interesting article.

       Despite being the warmest decade on record, the last decade has seen a slowdown in the rate of global warming in some temperature datasets.

       Meehl et al 2011 provides references to support the statement that "the observed energy imbalance at the top-of-atmosphere for this recent decade indicates... a net energy flux into the climate system of about 1 W /m²" - unfortunately I can't see what those references are, on the Nature site. Does anyone know? Obviously we don't have a way of reliably measuring the energy content of the entire climate system but if we can reliably measure a TOA energy imbalance then we know for sure that the energy content is increasing. Is it reasonable to take the increasing global sea level over the last decade as confirmation that there has been no slowdown in increasing total energy content? - Can regional sea level, gravity or any other satellite data tell us anything about temperature changes in the deep ocean, if we haven't got adequate ways of measuring it in situ?
73325. Old Mole at 08:31 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       My problem with Dr.Pielke's analysis is that it undercuts the "moral hazard" arguments discussed on other threads. If CO2 is only responsible for about a quarter of climate change, and land use is the determining factor for regional effects, the industrialized world has far less responsibility for catastrophes in tropical regions, since by his logic, they will be their own fault. Tropical rain forests are the lungs of the planet, and essential for everyone on it ... but they have no economic value unless logged or cleared for agricultural use. This is probably the most extreme market failure in the history of capitalism.
73326. Chris G at 07:26 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       I am coming around to the conclusion that the disagreement is mostly related to Dr. Pielke's not acknowledging the positive forcing feedbacks, dominated by water vapor, but I suspect methane should be included (thawing permafrost and clathrates), that are a direct result of the initial driving force of the increase in CO2. Looking around for statements made by him on the subject of water vapor, his seems to be an argument of uncertainty.
73327. Chris G at 07:01 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       So, if someone disagrees with the definition with the definition of "forcing" as I am using it, I'd be happier if you would just say so. We are all capable of rational disagreements here. I don't think it matters a great deal though, just different words applied to the same physical processes. In any event, I was thinking about the math some more. If you use the definition, "Climate forcing An energy imbalance imposed on the climate system either externally or by human activities." you would therefore include an increase in water vapor as contributing to the radiative imbalance. Then, if you use a 1.2 K estimate of no-feedback warming that could be attributed to a doubling of CO2, and you combine that with Dr. Pielke's estimate that the positive radiative forcing of CO2 is only 26% of the total forcing, then you end up with something like a warming sensitivity to a doubling of CO2 in the 4.5 K ballpark (1.2/0.26 ~= 4.5), minus negative forcings. Obviously a back-of-the-napkin estimate, and I have slightly abused the 26% number because it was provided in the context of forcing so far rather than forcing for 2x, but that is pretty close to a mainstream estimate. It may be that Dr. Pielke, Sr. has not arrived at estimates that differ by much from the mainstream, but the way he frames his statements makes it seem that way.
73328. muoncounter at 06:21 AM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       These decadal studies leave me unimpressed. Bill Chameides at Duke has a very similar posting, in which he shows this graph: Looking from the change between decadal averages since the 70s, it sure looks like the same 0.16C per decade. That is consistent with tamino's how fast is earth warming? trend. Where's the stall?
73329. Rob Painting at 06:12 AM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       Yes John, but the Antarctic Oscillation Index is strongly negative - so down here in New Zealand, we're copping a lot of cold & unsettled weather. It sucks!
73330. caerbannog at 05:47 AM on 2 October 2011
       Understanding climate denial
       Michael Mann certainly understands climate denial, and he has learned how to give deniers all the respect that they deserve. Here's an example of how Dr. Mann is now dealing with deniers. Mann just responded to a denier hit-piece that was published on-line, and boy did he take the gloves off! You can read his piece here. I'd like to encourage folks here to follow the link to Mann's piece and click on the "recommend" button at the top of the page. Also, tweet it, facebook it, do whatever you can to spread Mann's words far and wide.
73331. John Russell at 04:50 AM on 2 October 2011
       The Deep Ocean Warms When Global Surface Temperatures Stall
       "...the last decade has seen a slowdown in the rate of global warming..." Of course it has very little significance in scientific terms but, fwiw, today was the hottest October day ever recorded in the UK -- 29.9C. Very pleasant it was too.
73332. muoncounter at 04:33 AM on 2 October 2011
       Climate Change Could be Expensive for Canada
       It's a double whammy, per Kurz et al 2008, as: the resulting widespread tree mortality reduces forest carbon uptake and increases future emissions from the decay of killed trees. This impact converted the forest from a small net carbon sink to a large net carbon source both during and immediately after the outbreak. In the worst year, the impacts resulting from the beetle outbreak in British Columbia were equivalent to ~75% of the average annual direct forest fire emissions from all of Canada during 1959–1999. ... Climate change has contributed to the unprecedented extent and severity of this outbreak. For a 2006 MODIS image, see earthobservatory.
73333. Pete Dunkelberg at 03:44 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       How might RP Sr have arrived at 26% radiative forcing for CO2? see # 15. It has gone into "common knowledge". Thus the linked paper by Schmidt et al. is needed.
73334. Eric (skeptic) at 03:39 AM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       Muoncounter, my best guess is intensity will be up, but frequency is still an open question. In any case, named storms far from land barely reaching a 35kt threshold are not a very relevant example of extreme weather. Your explanation (a) could be valid when there is a low frequency of incidence making it difficult to pick out a trend (as is the case with intense TCs). With some forms of extreme weather your explanation (b) might be valid (e.g. floods which are localized and recurrent versus intense TCs which affect a much larger and newer area). Explanation (c) seems invalid to me since a more intense TC is almost always bad at landfall.
73335. Pete Dunkelberg at 03:38 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       What we all understand is that the increase in water vapor in response to the temperature increase caused by CO2 is a climate feedback. Trust Gavin: radiative forcing is a separate and important concept. Abstract of Schimdt et al. linked above:

       The relative contributions of atmospheric long-wave absorbers to the present-day global greenhouse effect are among the most misquoted statistics in public discussions of climate change. Much of the interest in these values is however due to an implicit assumption that these contributions are directly relevant for the question of climate sensitivity. Motivated by the need for a clear reference for this issue, we review the existing literature and use the Goddard Institute for Space Studies ModelE radiation module to provide an overview of the role of each absorber at the present-day and under doubled CO2. With a straightforward scheme for allocating overlaps, we find that water vapor is the dominant contributor (~50% of the effect), followed by clouds (~25%) and then CO2 with ~20%. All other absorbers play only minor roles. In a doubled CO2 scenario, this allocation is essentially unchanged, even though the magnitude of the total greenhouse effect is significantly larger than the initial radiative forcing, underscoring the importance of feedbacks from water vapor and clouds to climate sensitivity.

73336. Albatross at 03:29 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       Pete @19, Dr. Pielke was asked a very specific question "what fraction of the observed global warming is due to CO2 and other anthropogenic effects". In that context his answer makes no sense at all. Perhaps he misunderstood the question, but us arguing in circles is not going to shed much light on this. Dr. Pielke really now has two things to answer/explain 1) The original question and 2) explain how he arrived at 26% for radiative forcing for CO2. His numbers do not gel with the body of science on this issue. I hope that people do not get too focussed on this radiative forcing issue (at least not until we have more information from his side), because some of the other issues where Dr. Pielke is at odds with the body of knowledge are equally as critical.
73337. John Hartz at 03:29 AM on 2 October 2011
       Climate Change Could be Expensive for Canada
       “As the climate has warmed, various beetle species have marauded across the landscape, from Arizona to Alaska. The situation is worst in British Columbia, which has lost millions of trees across an area the size of Wisconsin. “The species Dr. Six was pointing out, the mountain pine beetle, has pushed farther north into Canada than ever recorded. The beetles have jumped the Rocky Mountains into Alberta, and fears are rising that they could spread across the continent as temperatures rise in coming decades. Standing on a mountain plateau south of Missoula, Dr. Six and Dr. Running pointed to the devastation the beetles had wrought in the forest around them, consisting of a high-elevation species called whitebark pine.” Source: “With Deaths of Forests, a Loss of Key Climate Protectors,” New York Times, Oct 1, 2011 To access this in-depth article, click here
73338. Pete Dunkelberg at 03:17 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       Dana,I know water vapor is not a climate forcing. So does Gavin Schmidt. That said, is not the disagreement between you and Dr Pielke Sr. based on talking about different things?
73339. muoncounter at 03:07 AM on 2 October 2011
       Climate Change Could be Expensive for Canada
       Today's NY Times has a multi-page spread (starting on p. 1) about forest loss. Apparently warmer temps mean the pine bark beetle and other pests thrive. It's not specific to Canada, but the Great White North does have a rather large forest products industry. -- source
       Moderator Response: [John Hartz] In this particular instance, "today" is Saturday, October 1 in the US. The time stamp for all posts is Australian.
73340. muoncounter at 01:54 AM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       Eric#137: Some valid points; we've been around the hurricane argument many times. Some studies say no trend, some say numbers and intensity increase. No studies say the trend is down; that warmer SSTs means everything will be nice and comfy. The point was, is and will remain thus: There are a significant number of extreme conditions around the world consistent with climate change; there is a valid physical mechanism for warming as the cause of said change and a valid physical mechanism for the cause of said warming. The explanations offered in response seem to cluster into a. 'older data is no good' or 'there's no trend,' which boil down to 'let's wait and see;' b. 'more people live in risky areas' or 'disaster counts don't mean anything,' which boil down to 'we're all gonna die eventually anyway;' c. 'this has all happened before' or 'its not that bad' or 'its just the weather,' which boil down to 'don't worry, be happy.' Has anyone seen a credible paper saying that conditions are getting milder?
73341. dana1981 at 01:41 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       Pete @15 - you're talking about percentage of the greenhouse effect, not percentage of positive radiative forcing. Water vapor is the largest contributor to the greenhouse effect, but not a forcing. Pete @17 - I noted in the post that the black carbon forcing may be underestimated. So may the aerosol negative forcing.
73342. Pete Dunkelberg at 01:37 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       The chart in the post may be based on out of date and inadequate data on black carbon. Compare for instance Jacobson_2010_Fossil_and_Biofuel_Soot_Climate_Effects.pdf (5.5 MB pdf). Mark Z. Jacobson is a man who knows his soot. Whether he is equally sharp on climate forcing I don't know. Other reports that I don't have a link for just now indicate that black carbon in the atmosphere, over the Arctic in particular, may have been significantly underestimated.
73343. Chris G at 01:32 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       I think I may have gotten caught up in this a bit myself, but I think the distinction between a forcing and a total effect is being blurred. There was a pre-industrial (and pre-agricultural) balance of total radiative energy effects. A change in any of the contributing factors is a forcing. So, saying that the total attribution of CO2 is x is not the same as saying that the forcing is x; the forcing will be some other number determined by how much it has changed and how much that change affects the balance. If CO2 had not changed, its percentage of any positive forcing would be 0%. Let us pretend that you could double CO2 and hold everything else constant. The forcing would be on the order of ln(2) * x, where x was whatever its total contribution was before. But from a percentage standpoint, 100% of the positive forcing would be from CO2. If you account for an increase in water vapor, then the attribution of the positive forcing would be something less than 100%, and so on. Water vapor is a feedback, not an initial forcing, but, it does change the radiative energy balance, and sticking by the definition at the NRC link above, that makes it a forcing. Dr. Pielke is saying that CO2 is only about 1/4 of the positive forcing, which means that the other positive forcings are three times larger in effect than the ~40% change in CO2. At this point, I don't know; maybe that number is not that far off if water vapor contributes a large portion of the remaining 74%. However, that would mean that Dr. Pielke is making a fairly serious omission by not mentioning that it is our CO2 that is driving the increase in water vapor.
73344. Eric (skeptic) at 01:11 AM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       Muoncounter, there are two problems with your lower graphic. First there is an undercount of North Atlantic TCs in early years. Landsea 2007 estimated it at 2.2 for 1900-1965 Mann et al 2007 countered with an undercount of 1.2 pre-1944. The problem that neither paper analyzed was more recent overcounts in named storms that is exaggerated by the 10 year moving average and truncated vertical axis in your chart. Typically the overcounting is in the eastern Atlantic using modern satellite coverage. Here is an example from last year http://www.nhc.noaa.gov/archive/2010/GASTON.shtml? where TC Gaston briefly reached 35 knots by satellite estimate (no surface or dropsonde measurements), got named, and drifted west for a week as a minor disturbance still named in the discussions so that if it came back to life it would keep the name. The Landsea paper resulted in this graphic:
       
73345. Bob Lacatena at 00:22 AM on 2 October 2011
       Climate Change Could be Expensive for Canada
       16, ianw01,

       Are those of you chiming in to denounce him advocating ... [that there] are no benefits to climate change at all [?]

       I would simply warn that most imagined benefits are only superficially conceived, and are unlikely to come to fruition. A study of the actual impact of climate change on agriculture -- the very narrow range of light, temperature, moisture, and seasons in which selected crops thrive, and the serious efforts that must already be made to overcome pests and natural weather variations -- shows that imagined increases in crop production are only that. The same applies to fanciful thoughts that "warming" will mean fewer winter deaths and cheaper winter heating bills. Canada will continue to have only 8 hours of very low incidence sunlight in the winter. It's still going to get darn cold. At the same time, if buildings are constructed and insulated to protect against cold, not heat, but summer temperatures skyrocket by 5˚C or 10˚C, then that represents a problem. The bottom line is that a lot of factors are going to change: winter temps, daytime temps, humidity, weather patterns, precipitation patterns, floods, droughts, sea levels, dangerous pests, etc. And it only takes one of these to muck up the works. So many factors are going to change that it is very, very unlikely that there is any aspect of life or economics that is going to get only benefits and no detriments. How do you think the Napa Valley wine growers are going to feel when that is no longer wine country? Or every farmer in Texas when that state is no longer a viable agricultural contributor? On top of this, you have to look at the extremes. We are not talking about what has happened to date. What you see now is nothing. We're talking about what is going to happen. That is going to be a lot worse. Trying to imagine benefits is, to me, clutching at straws to try to pretend that there is no problem. It's too complicated, and the changes are too varied and too extreme for anyone but a handful of individuals to benefit in the long run. Things are going to change. Change is expensive. Change requires adaptation. New building techniques, new equipment, new insulation, new air conditioners, new behavioral habits, etc., etc. Even "good" change is expensive. Every change requires some degree of adaptation, which requires effort above and beyond what we need to expend today. You see a lack of balance because benefits aren't included. I see a lack of true appreciation of how complicated and nasty things are ultimately going to get when I hear such complaints.
73346. Eric (skeptic) at 00:17 AM on 2 October 2011
       Review of Rough Winds: Extreme Weather and Climate Change by James Powell
       Norman #133 "I had pointed out that warmer low temperatures are not dangerous to the human life, that 2011 had 3 F warmer nights is not the important stat for extreme weather. It is the very high temperatures that lead to fatalities via heat stroke." Heat stroke is not the only hazardous outcome. Warmer low temperature can lead to heat exhaustion and mortality. Kalkstein and Davis (1989) http://coaps.fsu.edu/pub/williams/Thesis/2563853.pdf point out that in most statistical models, (high) minimum dewpoints and minimum temperatures have a direct relation to mortality.
73347. Bernard J. at 00:14 AM on 2 October 2011
       2011 Sea Ice Minimum
       Dikran Marsupial. As a statistical exercise, those plots warm the cockles of my heart. As a hint of what may will come, they churn my innards. Of course, as you and others of us have noted above, they are not parametric modellings of the phenomena, and thus at some point the differing ice-free-summer projections of extent versus volume are going to knock one (or each other) over. It's interesting to consider how it will play out. For the trend in extent to hold into the future, something major would have to put a brake on the trajectory of (and thus on the causative factors for) loss of summer ice volume (= mostly thickness). That's a lot of 'inertia' with which to tangle. For the trend in volume to hold into the future, all that really needs to happen is for extent to suddenly collapse in magnitude, which can easily be anticipated once thickness reduces beyond a critical threshold. I think all wise money would be placed on the latter scenario: at some point between 2015 and 2050 (and probably very much in the first half of that period) there will be a spectacular plummetting of the values for sea ice extent. I'm still of the inclination to consider that it will likely occur before 2020. Whenever it does eventually happen, it will be instructive to see how humanity responds...
73348. Pete Dunkelberg at 00:11 AM on 2 October 2011
       Pielke Sr. and SkS Disagreements and Open Questions
       You say '"...Dr. Pielke responded: "~26% of the positive radiative forcing was from CO2"' This may be an overestimate, not an underestimate. Schmidt et al. 2010. Attribution of the present-day total greenhouse effect finds just 20% of it due to CO2. See also NASA, Real Climate. Dr Schmidt says at RC

       One amusing aspect of the process was that one of the referees initially suggested that our paper wasn’t necessary because it was common knowledge that the attribution to CO2 was between 9 and 26% (sound familiar?). As it turns out, they were reading a page from UCAR which was quoting (without attribution!) from my original blog post.

       The chart you show at the top of the post is talking about something else. Evidently the chart folds the water vapor feedback into CO2. It looks like a chart of climate forcings, not radiative forcings, so that you and Dr Pielke Sr. are talking about different things.
73349. Glenn Tamblyn at 21:34 PM on 1 October 2011
       Modern scientists, following in Galileo’s footsteps
       Les "Clearly the 'skeptics' comparing them selves to Galileo shows a very poor understanding of history". But maybe it gives a very clear understanding of the egotism/rightious victim mentality that they embrace so whole-heartedly
73350. mspelto at 21:01 PM on 1 October 2011
       Climate Change Could be Expensive for Canada
       Energy costs will also be impacted by continued glacier retreat which will impact hydropower at locations like Bridge Glacier or Apex Glacier. In these locations declining summer glacier runoff will lead to lower hydropower production unless more water is stored at another time of the year, though that is not possible in many locations due to flood control.

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