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Comments 127601 to 127650:

127601. Alliecat at 18:22 PM on 5 August 2009
        Global warming and the El Niño Southern Oscillation
        One "minor" problem with all this - the correct figure is that ENSO accounts for only 3.6% of the variation, not the 70% claimed by McLean et al. See http://tamino.wordpress.com for the correct way to calculate the correlation between the SOI and the tropospheric temp anomaly.
127602. Lee Grable at 16:03 PM on 4 August 2009
        Global warming and the El Niño Southern Oscillation
        Haven't real climate scientists already hashed this out already?
127603. thingadonta at 14:12 PM on 4 August 2009
        Global warming and the El Niño Southern Oscillation
        RE 21: Robbo. Yes to most of the above. cheers.
127604. Robbo the Yobbo at 13:53 PM on 4 August 2009
        Global warming and the El Niño Southern Oscillation
        Thinga, I was taking issue with the point that John Cook made of the SOI not having a trend. It does. More positive in the mid 1940's to the mid 1970's and more negative to the late 1990's. This is simply a refection of the state of the Pacific Ocean. More frequent La Nina and a negative PDO followed by more frequent El Nino and a positive PDO. The 20 to 30 cycles are real oceanographic and atmospheric phenomenon. The point is how to assess that statistically (or theoretically)- and no simple approach springs to mind. I would suggest that integrating changes in shortwave forcing – see below – in the models is the next cab off the rank. McLean et al are explicit in the discussion on decadal climate shifts – particularly the “Great Pacific Climate Shift” of 1976/1977 and it is far from being McLean et al on their lonesome. It is disappointing that this discussion keeps occurring at all – it is not as if there is not a huge literature on this. Indeed the global whiners were quick to claim the climate shift as a symptom of global warming – before it turned around. Now they can’t back flip fast enough. The McLean et al paper takes the first derivative of the time series to filter out chaotic noise. While the method can't say how ENSO contributed to trend - the variation is almost all ENSO - 70 to 80% with a seven month lag behind the SOI. A nice little scientific result. It quantitatively shows that ENSO is by far the biggest influence on global surface temps - so you would expect a period of more intense and frequent El Nino (from 1976 to 1998) to boost surface temps. If that is not proven beyond doubt yet - it is a fairly solid hypothesis and made much more so by the quantified McLean et al results. It throws another interesting sidelight on the GCM. What the climate modelers do is take the bottom of the 1976 La Nina and the top of the 1998 El Nino and call that the recent trend in warming due to greenhouse gases - totally bogus cherry picking. If you exclude 1976 and 1998 - after Swanson and Tsonis- the trend from all other factors is about 0.1 degree C/decade. If you take the long term trend from 1850 – it is about 0.1 degrees per decade. If you take the 1946 to 1998 period the trend is about 0.08 degrees C/decade. Any of these is a reasonable estimate of background warming from all other factors. The current IPCC expectation of 0.2 degree C/decade in the next few decades is obviously not presently being met. On positive AGW feedback, indeed there is a very recent paper by Clement, Burgman and Norris - Observational and Model Evidence for Positive Low-level Cloud feedback which shows an interesting connection between multidecadal cloud changes and decadal changes in ocean indices. It posits a positive global warming feedback between the mid 1970's and the late 1990's from reduced cloud cover. i.e it wasn't greenhouse gases but feedback involving increased shortwave forcing. Trenberth and Fasula 2009, Palle and Goode 2009 - essentially say that clouds were involved (and I have referenced both of these previously) - and suggest that we need to get on top of the cloud variable. As long as Earth albedo persists at the current level – the planet will have about 2 W/m2 less shortwave at the surface than in the late 1990’s – see Project Earthshine – a cooling influence. I believe that the decadal changes in global ocean indices are driven by changes in clouds. The $64 dollar question is what drives decadal changes in clouds? On a final note - I was expecting the IPCC to moderate their projections in 2007 – so don't hold your breath Although with people like Swanson and Tsonis and Trenberth and Fasulu reassessing their position – there may be hope yet. Cheers Robbo
127605. thingadonta at 19:17 PM on 3 August 2009
        Global warming and the El Niño Southern Oscillation
        Robbo I think the AGW skeptics suggest that the shift in the PDO to a warm cycle from the late 1970s enhances the 'warming trend' from the 1980s-1990s and the associated El Ninos in this period, although if there is little/no influence from greenhouse gases during these decades one would also expect a similar drop in T and stronger El Ninas once the PDO shifts back to negative, from ~the early 2000s. In other words, the main problem with the Mclean (2009) paper remains, the longer term warming (recently flattening) trend, regardless of what the PDO or El Ninos are doing in the short term. At any rate, if the 'PDO shift' idea is anyway influential on earth T, the warming from C02 since the 1970s may have been over-estimated from the AGW camp, as one would expect both 1) stronger El Ninos in the 1980s-1990s(as you mention) and 2)the warm PDO cycle, BOTH to be superimposed on the longer term warming trend, to together produce a more strongly enhanced warming from the late 1970s-1990s. The flat T trend since the early 2000s supports this angle (with the shift back to a cooler PDO), although T should really be dropping further-back to 1970s temperatures-if greenhouse gases aren't really doing anything, and the question remains as to why the longer term warming trend appears to continue. (Notwithstanding a possible heat lag from peak solar activity in the mid-late 20th century, and Hansen's 2005 probably miscalculated/ misinterpreted 'disequilibrium'-already being dicredited since T isn't rising since the early 2000s, despite his predictions when he released the 2005 paper), albeit since the early 2000s at a flattened rate than the AGW proponents have argued. The AGW are now claiming 'internal variability' for the pause in warming since the early 2000s (eg from PDOs, ocean absorption etc), but they cant have it both ways (internal variability/negative feebdbacks now, but not positive feedback/enhancements in the period 1970s-1990s), therefore it is indeed likely c02/greehouse gas influence has been over-estimated for the period 1970s-1990s, which started the whole AGW thing off in the first place. In 2011 when the IPCC once again reports, they will have to scale back their T forecasts, if they are to be consistent methinks.
127606. Robbo the Yobbo at 11:52 AM on 3 August 2009
        Global warming and the El Niño Southern Oscillation
        The SOI does show 20 to 30 year cycles. A shift from a negative bias to the 1970's to a positive bias to the late 1990's - in a decadal timescale this is a trend. It must have this pattern as a result of the "Great Pacific Climate Shift of 1976/1977". More and bigger El Nino since the mid 1970's than before as a consequence of 'chaotic dynamical climate shifts'.
127607. Gareth at 07:37 AM on 3 August 2009
        Global warming and the El Niño Southern Oscillation
        Small point: Phil de Freitas = English cricketer of yesteryear. Chris de Freitas = Auckland University academic with a penchant for climate denial...
        Response: Damn, this is what happens when I stay up late watching the Ashes.
127608. Tiranse at 05:16 AM on 3 August 2009
        There is no consensus
        So where does the Scientific Method inject "consensus" into conclusion? Consensus, by definition, is a social and political construct that has no use in real science.
127609. Tiranse at 05:12 AM on 3 August 2009
        Satellites show no warming in the troposphere
        Thingadonta: Frankly, your post gets closer to Truth than anything else I've read here. It is a history proven fact that humans, are...well human...and will do much to dig-in on a vested position to avoid 1) loss of credibility, 2) loss of real or perceived power, and the age old 3) loss of $$ (i.e funding). Real science has *never* been based on consensus -- it has been driven by those that are usually well outside the consensus. Otherwise, we'd all believe that the earth was the center of our universe. The lack of real, public debate on what may be the most important issue of our time does not exist. That is frightening.
127610. canbanjo at 23:52 PM on 2 August 2009
        Global warming and the El Niño Southern Oscillation
        John, Bob does say his paper 'does not address trends as such'. So his statements seem rather contradictory. I have asked him to clarify, no response yet.
127611. Quietman at 13:14 PM on 2 August 2009
        Global warming and the El Niño Southern Oscillation
        All 8 pages instead of the Abtract in John's Link: Influence of the Southern Oscillation on tropospheric temperature J. D. McLean,1 C. R. de Freitas,2 and R. M. Carter3 Received 16 December 2008; revised 23 March 2009; accepted 14 May 2009; published 23 July 2009. http://climatedebatedaily.com/southern_oscillation.pdf
127612. David Horton at 09:09 AM on 2 August 2009
        Global warming and the El Niño Southern Oscillation
        I love "The paper does not address trends as such (which Real Climate and similar websites often appear to be obsessed by)." Who would have thought?
127613. canbanjo at 08:34 AM on 2 August 2009
        Global warming and the El Niño Southern Oscillation
        Thanks Chris, I sent an e-mail to Bob Carter to get his side of the story, he responded as follows (the websites he refers to are this one and realclimate): Dear canbanjo, Thank you for your interest in our paper. There is little point in my responding to ridicule when that ridicule is based upon wilful misunderstanding of the science in question. Unfortunately neither of the web sites that you mention provide dispassionate scientific analysis of the AGW issue, and they are therefore not sites that I spend time reading. For their authors are primarily committed to defending against all comers the IPCC's hypothesis of dangerous human-caused warming, rather than testing it independently. The McLean et al. paper supports earlier understanding of the effects of ENSO and volcanic eruptions on the climate system, and shows that much of the variance in the global temperature record can be explained by changes in ENSO 7 months prior. That fact leaves no room for a major influence from human carbon dioxide emissions, and cannot simply be shrugged of. The paper does not address trends as such (which Real Climate and similar websites often appear to be obsessed by). I attach a leaflet which contains some recommended websites and other sources of information on AGW that are of higher quality, and exhibit better scientific balance, than the two that you are currently relying upon. Thanks again for writing. With kind regards. Bob Carter Professor R.M. Carter Marine Geophysical Laboratory James Cook University Townsville, Qld. 4811 AUSTRALIA Phone: +61-7-4781-4397 Fax: +61-7-4781-4334 Home: +61-7-4775-1268 Mobile: 0419-701-139
        Response: Thanks for posting the response from Bob Carter. I'd read some comments from Phil deFreitas which seemed to be backpedalling somewhat - saying that the paper proved El Nino caused short term variations but not the long term trend. So I worried I may be misrepresenting their position, setting up a strawman argument. But Bob Carter is definitely still sticking to the story that El Nino causes long term trends.
127614. Philippe Chantreau at 03:31 AM on 2 August 2009
        Global warming and the El Niño Southern Oscillation
        We have discussed this already in a surface temp related post quite some time ago. Considering the stratospheric influence on satellite measurements, unadjusted data is of little usefulness. These papers probably had some subsequent research but they are a good way to start. http://www.ncdc.noaa.gov/oa/climate/research/rss-msu.pdf http://climate.envsci.rutgers.edu/pdf/VinnikovGrody2003.pdf Revised 2005 version: http://climate.envsci.rutgers.edu/pdf/TrendsJGRrevised3InPress.pdf Vinnikov and Grody disagree that trying to remove the stratospheric influence, which is what Fu did, is a better idea than their treatment. http://www.ncdc.noaa.gov/oa/climate/research/nature02524-UW-MSU.pdf Overall the surface temperature records for both GISS and HadCRUT agree very well with the satellites. Tamino has shown that already: http://tamino.files.wordpress.com/2007/08/global2.jpg In addition, it is not obvious at all that satellite measurement are overall more accurate than surface. There was some disagreement with some balloon data, which was then examined more closely and shown to be defective due to similar diurnal problems as the satellite data: http://www.sciencemag.org/cgi/content/short/309/5740/1556 Watts has now "surveyed" enough surface stations to do a good preliminary analysis. Strangely enough, no data analysis has yet been done on his web site but NCDC did one, which confirms what John V had already shown at the beginning. http://www.ncdc.noaa.gov/oa/about/response-v2.pdf Data analysis does not show microsite effect to introduce any significant bias. UHI has been closely examined before: http://www.ncdc.noaa.gov/oa/climate/research/population/article2abstract.pdf http://www.ncdc.noaa.gov/oa/climate/research/population/article3abstract.pdf Nonetheless, GISS corrects for UHI. Sorry for the OT John.
127615. thingadonta at 12:42 PM on 1 August 2009
        Global warming and the El Niño Southern Oscillation
        It is also a case of whether or not one uses unadjusted satellite trophosphere data, or 'flawed' surface data.?
        Response: The UAH temperature record is adjusted for diurnal drift as is the RSS satellite record. In fact, the main reason for the difference between the two records is how they adjust the data - UAH imposes a cooling effect while RSS imposes a warming effect.
127616. chris at 06:44 AM on 1 August 2009
        Global warming and the El Niño Southern Oscillation
        It's the latter canbanjo. The paper is a run of the mill restatement of the well understood fact that the year on year variability in the global surface temperature is dominated by ENSO (warmer in/shortly after El Nino years; coooler in/after La Nina's)....volcanoes also have a strong effect on variability without having much effect on the long term trend. Incidentally, the same applies to the year on year variability in atmospheric CO2 levels which is also dominated by El Nino/La Nina, despite the latter having essentially no effect on the long term trend . So the paper very clearly has nothing whatsoever to say about the long term warming trend since 1958. In fact (as John Cook describes very cogently) the method of analysis eliminates this trend. The problem is that at least one of the authors has chosen to misrepresent their own paper, for reasons which are all too apparent. It's the latter that is appalling rubbish. One can see how easy it might be to give the impression that a dominant contribution of ENSO to temperature variability is misconstrued to imply a dominant contribution to the long term change in temperature. Normally scientists are extremely careful to ensure that they are clear about what their work actually means. Something is clearly awry in the scientific integrity of at least one of the authors of that paper....the only other interpretation is that this author is simply ignorant of the methodologies, consequences and interpretions of a paper to which he has put his name... Incidentally, one might argue that the overall atmospheric/ocean circulation/interactions, of which ENSO is a part, do influence the rate at which heat accumulates in the oceans as a result of radiative imbalance, since presumably ENSO phenomena are part of the "mechanisms" by which excess heat is distributed through the oceans. Thus the more effective the mixing of surface and deeper waters the more quickly the oceans as a whole, will come towards eqilibrium with any radiative imbalance. Thus all circulation processes per se might be expected to slow the rate of warming as experienced at the surface (our land/ocean surface temperature anomalies as compiled by NASA Giss/Hadley/NOAA), since heat that accumulates in the upper ocean layers is more efficiently moved from the surface to the deeper layers, and thus makes less of a contribution to the temperature that we "surface dwellers" experience. The overall equilibrium temperature under the influence of a particular radiative imbalance will, however, be independent of this. That's how I think of this anyway! However this latter issue is not a part of the paper under discussion; these phenomena (ocean mixing and ocean/surface/atmosphere heat transfer) are included in Global Circulation Models....
127617. canbanjo at 05:29 AM on 1 August 2009
        Global warming and the El Niño Southern Oscillation
        How did this paper get published, if it is clearly distorting the truth, or is it a case of the actual paper being factual, and then the authors subsequent comments jumping to unjustified conclusions?
127618. thingadonta at 13:33 PM on 30 July 2009
        Global warming and the El Niño Southern Oscillation
        A better link on changes in low cloud cover. http://www.sciencedaily.com/releases/2009/07/090723141812.htm
127619. David Horton at 12:02 PM on 30 July 2009
        Global warming and the El Niño Southern Oscillation
        "I seem to rememer that El Nino 1998 was a low loud year" unlike 2009 which seems to be a high loud year for denialists. Pearls before swine, John Cook, pearls before swine.
127620. thingadonta at 11:36 AM on 30 July 2009
        Global warming and the El Niño Southern Oscillation
        As an aside: Here is a link to the idea that warming produces less low level clouds, thereby further enhancing any warming (like any sunny day once the low clouds are 'burned' off). It's just common sense, especially over surface temperate zones, where most 20th century warming has occured. It will magnify any warming trend, regardless of cause (solar or greenhouse gas). http://www.guardian.co.uk/environment/2009/jul/23/cloud-cover-oceans-global-warming. Unfortunately, the article doesn't link the actual paper. Its interesting though how they get it wrong, the article concludes less low level clouds means that clouds won't reduce greenhouse gas warming, when its warming that is reducing low level cloud cover. Love those 17th century cloudy, Little Ice Age, European paintings! (I seem to rememer that El Nino 1998 was a low loud year?).
127621. Robbo the Yobbo at 05:44 AM on 30 July 2009
        Global warming and the El Niño Southern Oscillation
        The ENSO component of warming between 1976 and 1998 has 2 components. The climate shifts (e.g. Swanson and Tsonis) in 1976/1977 and 2001/2002. The other contribution atmospheric heat is ENSO decadal variation. Cool La Nina to the mid 1970's, warm El Nino to 1998, cool La Nina since. http://www.cdc.noaa .gov/people/klaus.wolter/MEI/
127622. Philippe Chantreau at 04:40 AM on 30 July 2009
        Global warming and the El Niño Southern Oscillation
        The link to the Wong 2005 paper does not work, can it be fixed, or the complete reference shown?
        Response: Fixed, thanks for the tip.
127623. Mizimi at 04:39 AM on 30 July 2009
        Global warming and the El Niño Southern Oscillation
        Eyeballing the SOI graph some things appear to me: 1. There is an apparent(slight - maybe my eyes!) downward trend and 2. The bandwidth of the oscillation has declined, particularly since 1998. 3. One would expect the lag between the graphs to be reasonably consistent, ( volcanic activity excepted)yet GTTI begins to decline in 2003 before SOI has peaked. Also that GHC trend is a bit misleading. It's a big figure but in context equates to around 0.05C/annum if we assume it is restricted to the top 1000m of the oceans.
127624. Steve L at 01:02 AM on 30 July 2009
        Global warming and the El Niño Southern Oscillation
        Actually, Thingadonta, I think what John is saying is that McLean et al are incorrectly concluding that short term relationships between SOI and T mean there is no other cause for the long term warming trend. He's also saying that the relationship between ENSO and Temperature is NOT close unless you remove the long term trend in T.
127625. thingadonta at 22:09 PM on 29 July 2009
        Global warming and the El Niño Southern Oscillation
        Am I correct in saying that if there really is a close relationship between ENSO and earth T since the 1950s/1980s, you are saying it doesn't say anything about the longer term temperature rise, along with the build up of ocean heat over the longer term?
127626. XPLAlN at 20:28 PM on 29 July 2009
        Global warming and the El Niño Southern Oscillation
        Thanks. As usual you have presented the material with both clarity and brevity.
127627. thingadonta at 19:46 PM on 29 July 2009
        Climate time lag
        re:287 Chris: I've never seen a Sophia Loren movie with anything to do with biodiversity but I wish I had. I'm extremely skeptical from my readings in geology that warmer periods dont correlate with biodiversity, and with higher c02, but I would have to read the recent papers. I hope they arent twisting the evidence. I think those papers may be actually examining 'rates' of warming, and smearing this into 'general' warming periods, but I would have to read them. I DO know that there is an association with increased desertification and colder periods. Deserts, for example expanded and savannahs increased in Africa around 4-7 Ma as the earth continued to cool, which is quite possibly how the savannah ape evolved (and argues about such effects). We are here probably because cooling shut down the forests in Africa, and enlarged the savannah, possibly also changing the balance of savannah peak/predator relationships etc and the availability of meat with the increase in grazing animals. Ice ages followed which may have gradually enhanced our dominance over other animals through reduced predation? etc. I certainly think there is some connection to the evolution of intelligence and the onset of worldwide ice ages, possibly with a concomittant reduction in competition/ biodiversity/predator-prey relationships (??). You didn't address the PETM 55 Ma mammalian explosion- one can read about it on the WIKI PETM entry. Makes an interesting connection though, severe stress then explosive evolution? What is going on here? Does severe stress increase rates of speciation, or does it produce extinction? Seems like more climate ambiguities. I am just thinking out loud, but thanks for the papers.
127628. Robbo the Yobbo at 19:33 PM on 29 July 2009
        Climate time lag
        "The heat doesn't hide, this is the kind of ..." There might be some heat hiding in melted ice and parmafrost as internal kinetic energy equal to the enthalpy of fusion of water. This is a millimetre/year currently as melted icewater in the oceans. And some soil warms up. So where is all the heat from the radiative imbalance of the planet hiding? As it is apparently not in the oceans or atmosphere. Biology thives within reason I said and the anthropogenic C02 flux is a fraction of the natural cycle - most especially that below the thermocline. Cheers Robbo
127629. chris at 17:57 PM on 29 July 2009
        Climate time lag
        re #288 Not realy thingadonta. The notion that biodiversity thrives under high CO2/warm-hot periods is one of those fallacies that one thinks must be true, but actually seems not to be. We've already seen that most of the major extinction events through the Phanerozoic are associated (where this is characterized) with greenhouse gas enhancement through tectonic processes, high temperatures, ocean acidification/anoxia etc. (see my post #257). In the more general case, high temperaures are associated with low biodiversity and vice versa, as indiated by detailed examination of the fossil record: *PJ Mayhew et al. (2007) A long-term association between global temperature and biodiversity, origination and extinction in the fossil record Proceedings of The Royal Society B 275, 47–53. Abstract: The past relationship between global temperature and levels of biological diversity is of increasing concern due to anthropogenic climate warming. However, no consistent link between these variables has yet been demonstrated. We analysed the fossil record for the last 520Myr against estimates of low latitude sea surface temperature for the same period. We found that global biodiversity (the richness of families and genera) is related to temperature and has been relatively low during warm 'greenhouse' phases, while during the same phases extinction and origination rates of taxonomic lineages have been relatively high. These findings are consistent for terrestrial and marine environments and are robust to a number of alternative assumptions and potential biases. Our results provide the first clear evidence that global climate may explain substantial variation in the fossil record in a simple and consistent manner. Our findings may have implications for extinction and biodiversity change under future climate warming. Hollywood films with Sophia Loren are simply not a good means of informing oneself on the subject of biodiversity. One really has to address the evidence ! Likewise, high temperatures seem to have the effect of greatly delaying for long, long periods, the recovery of biodiversity following greenhouse-induced extinction events; e.g. : Fraiser ML et al. (2007) Elevated atmospheric CO2 and the delayed biotic recovery from the end-Permian mass extinction Palaeogeog. Palaeoclim. Paleoecol. 252, 164-175 Abstract: Excessive CO2 in the Earth ocean-atmosphere system may have been a significant factor in causing the end-Permian mass extinction. CO2 injected into the atmosphere by the Siberian Traps has been postulated as a major factor leading to the end-Permian mass extinction by facilitating global warming, widespread ocean stratification, and development of anoxic, euxinic and CO2-rich deep waters. A broad incursion of this toxic deep water into the surface ocean may have caused this mass extinction. Although previous studies of the role of excessive CO2 have focused on these "bottom-up" effects emanating from the deep ocean, "top-down" effects of increasing atmosphere CO2 concentrations on ocean-surface waters and biota have not previously been explored. Passive diffusion of atmospheric CO2 into ocean-surface waters decreases the pH and CaCO3 saturation state of seawater, causing a physiological and biocalcification crisis for many marine invertebrates. While both "bottom-up" and "top-down" mechanisms may have contributed to the relatively short-term biotic devastation of the end-Permian mass extinction, such a "top-down" physiological and biocalcification crisis would have had long-term effects and might have contributed to the protracted 5- to 6-million-year-long delay in biotic recovery following this mass extinction. Earth's Modern marine biota may experience similar "top-down" CO2 stresses if anthropogenic input of atmosphere/ocean CO2 continues to rise. The contemporary situation is potentially very serious due to the rapid rate of change, combined with the equally problematic (if not more serious right now), confounding issues of massive deforestation, more generalised habitat destruction/degradation and over-exploitation: Brook BW (et al. (2008) "Synergies among extinction drivers under global change" Trends in Ecology and Evol. 23, 453-460 Abstract: If habitat destruction or overexploitation of populations is severe, species loss can occur directly and abruptly. Yet the final descent to extinction is often driven by synergistic processes (amplifying feedbacks) that can be disconnected from the original cause of decline. We review recent observational, experimental and metaanalytic work which together show that owing to interacting and self-reinforcing processes, estimates of extinction risk for most species are more severe than previously recognised. As such, conservation actions which only target single-threat drivers risk being inadequate because of the cascading effects caused by unmanaged synergies. Future work should focus on how climate change will interact with and accelerate ongoing threats to biodiversity, such as habitat degradation, overexploitation and invasive species
127630. thingadonta at 16:36 PM on 29 July 2009
        Climate time lag
        re:272 Chris "The fact that some dinosaur species thrived in a hot world nearly 200 million years ago is not a good marketing ploy for a suddenly hot contemporary world". Actually there was an adaptive radiation (explosion) of dinsoaurs in the Jurassic as the world warmed, c02 rose, and continents broke up. You emphasise the rate of c02 changes in biosphere adaptability etc, but this does skittle over one major point. High C02 geologically is associated with high biodiversity and thriving plant (feeding of the c02) and animal life (which feed off the plants). This is also why there was an explosion of mammallian evolution at PETM 55Ma (see Wiki entry on PETM). (Love that C02!). Colder climates are generally associated with increased worldwide desertification and extinction. Warm periods and higher c02 produces biodiversity. One certainly doesn't hear this from the AGW side. In fact there is no getting around it, even "requiring some rather bottom-squirming dissembling to argue away this evidence", as you might put it. However I do note that the contention here is the rate of change, rather than just the warming.
127631. thingadonta at 14:14 PM on 29 July 2009
        Climate time lag
        Hey Robbo, what about climate cool lag? Nobody has mentioned this yet. ('Where's my global warming dude' is a funny website. "The science is settled... but somebody forgot to tell mother nature".). I think the 'cool lag' (if that is the right word-I really don't think it is) in thermodynamics is usually a bit shorter than heat lag, but I'm not really sure about the timing and what magnitude occurs in cooling once a system reaches 'equilibrium' with heat slowly declining. This would have implications IF the sun is driving recent 20th warming and c02 has little effect; what is T then going to be doing in the next few years/decades?. The sun does appear to be waning slightly. Some of the russians (reputable qualified peer-reviewed published scientists, despite Horton's loud protests with a 'consensus' blindfold on-ie there is an 'overwhelming consensus', but only amongst those who agree with you), predict lower T over the next few decades levelling out around 2050? based on various sun analyses, but I dont know how 'immediate' this effect will be over the next few years, (if of course it is the sun driving warming recently). It might even be in line with the flattening of T over the next decade or so, as predicted by some alarmists (eg realclimate-probably to cover themselves), or perhaps they secretly believe the sun is the driver of recent T after all?
127632. David Horton at 13:32 PM on 29 July 2009
        Climate time lag
        Well Robbo, Thingy, it's been nice. Now that I've converted you guys you stay converted, you hear me? Stay away from denialist blogs and tabloid newspapers and books by geologists for awhile. Promise me now. Spend some time outside, smell the flowers, look for clouds in the shapes of animals, enjoy the sunsets. Think about the future. Have a great life.
127633. Robbo the Yobbo at 13:26 PM on 29 July 2009
        Climate time lag
        This is a nice story from NASA that examines the implications of solar irradiance changes over the 20th century. http://www.nasa.gov/centers/goddard/news/topstory/2003/0313irradiance.html I don't think anyone has ever said that CO2 is not a greenhouse gas - but that there are multiple other factors involved. Clouds have been addressed very poorly to date - by any account. Decadal climate shifts seem finally to be emerging from oceanograohy and hydrology into climate physics - and physicists still do not understand them very well. Look at the additional evidence on clouds in particular and - my favourite - the changes in SST surface temperature on decadal timescales that have decadal long implications for GMT and rainfall. It is not enough to go off on some other tangent and accuse me of being equivalent to a creationist.
127634. thingadonta at 12:47 PM on 29 July 2009
        Climate time lag
        RE:279 David, you need to re-examine your philosphical positions. Here are some points to consider. In complex, chaotic systems (EG stockmarket/economics, climate) the ones who usually get it wrong are those who over-simplify, and those who are over-confident in what can't be easily modelled or predicted. There is a fundamental difference here between complexity and simplicity, both viable scientific positions. This is largly the difference between views here, those who proscribe to complexity and chaos (e.g. in Crichton's Jurassic Park- the mathematician and 2 paleontologists, as opposed to the lawyer and developer- you know the story-which also neatly explains Crichtons position on global warming), and those who don't. "...an absolutely coherent picture". Your choice of words 'absolutly coherant picture' is revealing. This is an assumption taking the position of 'simplicity' in scientific systems, which also attmepts to smooth out 'chaos'. The trouble is, you are not dealing with a simple system. Small variations within complex chaotic systems can have large effects (this is also uually the reason that 'planned' economies fail). Medical research and cosmology also have aspects which are complex, and which are still uncertain. As does climate, such as just how much does the physics of rising c02 affect world temperature. World class physicists and many others still dont agree on this, they are not AIDS deniers or cheesy moon lunatics. They are reputable and varied scientists. Those who attmept to simplify uncertainties within complex systems are also often politically driven. As for "unprecedented and accelerating speed of warming". This sort of statement is not going to convince thinking scientists, because 1) you havent disentangled solar forcings and 2) it is simply not true. Temperature rose as fast or faster in Europe per decade immediately after/around the end of the Little Ice Age -per decade- than between the 1970s-1990s; T in the USA rose as fast in the decades to the 1930s compard to the decades to the 1990s. So the T rise it is not 'unprecedented' even in contemporary times. Neither is the rise 'accelerating', it is slowing down, or a relatively constant rise, depending on what starting and end points you use, (whether decadal, centurial or whatever). It is entirely comparable to previous rises-eg it is within normal variation/cycles, particularly the 1470 year solar cycle trend. You can keep parroting out these usual green phrases of 'unprecedented' and 'accelerating', but once a naive population is exposed to these sort of parroted phrases for long enough, they become immune, just like to a new virus, especially as the effects of the virus (meme)declines.
127635. David Horton at 12:46 PM on 29 July 2009
        Climate time lag
        The "paradigm shift" was the recognition that climate was changing as a result of greenhouse gas emissions. Your imaginary paradigm shifts are the result of a small group of people, with a range of motives, trying to turn the clock back. In this you are just like the creationists, who want to send biology back 200 years while pretending to be investigating "intelligent design". You might be fooling yourself Robbo, and I'll give you the benefit of the doubt that that is what you are doing, but you aren't fooling too many others.
127636. Robbo the Yobbo at 12:05 PM on 29 July 2009
        Climate time lag
        Science proceeds by examining the evidence. The evidence is for decreased cloud cover to 1998 and increased cloud cover since. There is an alternative strand of evidence on multidecadal climate shift. And yes - usually one scientist (and then a few more)does dramatically change the ways things are understood. These are caled paradigm shifts.
127637. David Horton at 11:32 AM on 29 July 2009
        Climate time lag
        Amazing how cherry pickers can continue to furiously cherry pick while complaining about being accused of being cherry pickers! Science doesn't work by selecting the odd paper here and there, and even just selecting sentences within one paper, while ignoring the massive weight of evidence in all kinds of disciplines. Consensus doesn't mean everybody conspiring to present some ideologically-driven view (and there must be at least as many right wing scientists as left wing, perhaps more, certainly in some disciplines), it means that the vast majority of scientists, and the published work, presents an absolutely coherent picture. Just as, say, cosmology does, or medical research. There may be odd niggling things here and there, or the odd scientist who remains certain of the cheesy composition of the moon, or that AIDS isn't caused by HIV, but even if such people fluke a hit, they don't affect the overall body of knowledge. So cherry pick away, but while you do, CO2 keeps rising, its greenhouse properties remain indisputable, temperatures rise, ice melts, climatic records continue to be set and odd events continue to occur, and plant and animal species begin to respond. The planet doesn't care about the cherry picking, just about the reality of an unprecedented and accelerating speed of warming.
127638. Robbo the Yobbo at 10:21 AM on 29 July 2009
        Climate time lag
        The amount of carbon conceivably released from volcanism etc is not sufficient to explain the spike in carbon in rocks during the PETM. Some mechanism such as methane release from clathate is required as an explanatory mechanism. Methane is oxidised in the atmosphere to carbon products and these are incorporated into the geologic record. As I understand it, Zeebe et al suggest that there is not enough carbon in the record to explain warming with current models. Again, I don’t see any point in this that can be applied to contemporary conditions. My point was that that citing the PETM as an example of climate sensitivity to carbon dioxide, and with absolute conviction, was misplaced enthusiasm. Lean et al are demonstrably wrong – you simply have to look at the ISCCP cloud reconstructions from any number of sources – try the CERES, Earthshine and ISCCP graph on the Project Earthshine site. About a one percent change in Earth albedo since 1998 – or a decrease of 2 W/m2 reaching the surface. There is a preprint of an article discussing this here. http://bbso.njit.edu/Research/EarthShine/literature/Palle_etal_2008_JGR.pdf Lean has not included the ‘climatologically significant’ shift Earth in albedo into their discussion. How can they possibly understand recent trends and predict the future? Note Swanson and Tsonis - half of the warming between 1976 and 1998 was decadal climate shift. Note Trenberth and Fasula on the imnportance of recognising the cloud effects in the planetary heat budget. Note Clements et al on a decline in cloud adding to warming between 1976 and 1998. Cloud cover that has since increased. Anything that doesn't fit the mold is cherry picking, dodgy, incorrect, misinterpreted, speculative or ignored by the global whiners.
127639. Robbo the Yobbo at 08:28 AM on 29 July 2009
        Climate time lag
        'Sadly, the tedious pretence that uncertainty over second-order (and often rather peripheral) elements of phenomena somehow constitutes cause for doubting the essential elements of our understanding is creepy, but perhaps it was ever thus where science impacts on politics and vested-interest!' Duh. Or is this snide and silly?
127640. chris at 08:24 AM on 29 July 2009
        Climate time lag
        Robbo (re #274), you can "absolutely repudiate without any qualification" all you want, but you were again using a paper that was subsequently shown to be incorrect, to pursue a dreary political point. you said in your political post #266 (discursions on "tantric-sex" and "water birth" and so on...): "The ocean acidification notion seems reminiscent of past environmental scares - very light on data heavy on fear tactics. Did you know that DDT was approved for use by the World Health Organisation in 2006? I had to read the document myself to believe it. In 2007, chemists at NASA’s JPL remeasured the photolysis rate of dichlorine peroxide at almost 1/10th of what was required to explain ozone depletion. Ozone depletion seems largely to be the result of increased UV from the sun. Acid rain was never a problem – plants are of course adapted to a range of environmental conditions. " So you were using Pope et al's provisional result to pursue a political point (about "fear tactics" apparently - the dreary notion that ozone-depletion by CFC's is some sort of conspiracy theory). However Pope et al. were wrong (nothing wrong with being wrong, of course!). As was Schwartz who you used to pursue a conspiracy theory point about climate sensitivity...as was Palle which you used to pursue a point about moonshine (literally!). Unfortunately, you're cherry-picking your sources according to a preconceived (non-scientific) world view. You don't make an effort to find out whether the rare "oh-so-convenient" study that suits your view might has been re-addressed in the meantime. You should at least run any paper more than a couple of years old through "Google Scholar" to determine whether anyone (including the authors themselves) might have reinterpreted their analyses.
127641. chris at 07:37 AM on 29 July 2009
        Climate time lag
        really Robbo? Where was the ad hominem? I pointed out that you misread the Zeebe paper and made a general point about "uncertainty" in science (my post #268); I pointed out that you (once again) made a big issue out of a paper that was subsequently shown to be incorrect, and made a general point about cherrypicking provisional interpretations in areas of scientific uncertainty (my post #269; you did this with the Palle paper you first introduced yourself with...you did it with the Schwartz paper on climate inertia...and now the Pope et al. paper) ...it's not ad hominem to point out things that are true. I was a bit cheeky in my post (#272). But playfully so - I hope you're not in a bad mood because you were beaten by the Poms at cricket last week (who's whinging now!). I did comment on the Clement et al paper I believe. It indicates that there is evidence of a positive feedback to warming in the cloud response. What else do you want me to say? I'd say it's rather provisional and not yet worth making a fuss over. Otherwise, I've introduced dozens of papers on this thread that you haven't commented on. Many of yours seem subsequently to be either effectively retracted (Schwartz), or shown to be incorrect (Palle; Pope et. al). No one suggested that Pope et al's mis-interpretation is "the end of the Earth". It's nothing of the sort...it's one of the glorious aspects of science to be wrong. The tedious thing is to jump upon provisional results that seem to go against the mainstream and use them to pursue political points. No one is taken in by that sort of advocacy, and it's not worth getting so worked up about stuff like that. As for your odd assertion of "the probability of no warming for another decade or two..." where on earth has that come from? Lean and Rind have a paper in press in Geophys. Res. Lett. that indicates that we're expecting some rather significant warming in the coming years [*]. So again there seems to be something wrong with your assertions. Have you been cherrypicking provisional analyses in areas of scientific uncertainty again? [*] Lean, J. L., and D. H. Rind (2009) "How will Earth's surface temperature change in future decades?" Geophys. Res. Lett., doi:10.1029/2009GL038932, in press. abstract: Reliable forecasts of climate change in the immediate future are difficult, especially on regional scales, where natural climate variations may amplify or mitigate anthropogenic warming in ways that numerical models capture poorly. By decomposing recent observed surface temperatures into components associated with ENSO, volcanic and solar activity, and anthropogenic influences, we anticipate global and regional changes in the next two decades. From 2009 to 2014, projected rises in anthropogenic influences and solar irradiance will increase global surface temperature 0.15 +/- 0.03 oC, at a rate 50% greater than predicted by IPCC. But as a result of declining solar acivity in the subsequent five years, average temperature in 2019 is only 0.03 +/- 0.01 oC warmer than 2014. The lack of overall warming is analogous to the period from 2002-2008 when decreasing solar irradiance also countered much of the anthropogenic warming. We further illustrate how a major volcanic eruption and a super ENSO would modify our global and regional temperature projections.
127642. Robbo the Yobbo at 07:36 AM on 29 July 2009
        Climate time lag
        The Pope abstract below – and links to a couple of recent blogs on the new study. I absolutely repudiate without any qualification any suggestion that I have misrepresented the science. http://rabett.blogspot.com/2009/07/science-lurches-forward-about-two-years.html http://chinese.eurekalert.org/en/pub_releases/2009-05/as-pmc050609.php Ultraviolet Absorption Spectrum of Chlorine Peroxide, ClOOCl Francis D. Pope, Jaron C. Hansen, Kyle D. Bayes, Randall R. Friedl, and Stanley P. Sander Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 J. Phys. Chem. A, 2007, 111 (20), pp 4322–4332 DOI: 10.1021/jp067660w Publication Date (Web): May 3, 2007 Abstract The photolysis of chlorine peroxide (ClOOCl) is understood to be a key step in the destruction of polar stratospheric ozone. This study generated and purified ClOOCl in a novel fashion, which resulted in spectra with low impurity levels and high peak absorbances. The ClOOCl was generated by laser photolysis of Cl2 in the presence of ozone, or by photolysis of ozone in the presence of CF2Cl2. The product ClOOCl was collected, along with small amounts of impurities, in a trap at about −125 °C. Gas-phase ultraviolet spectra were recorded using a long path cell and spectrograph/diode array detector as the trap was slowly warmed. The spectrum of ClOOCl could be fit with two Gaussian-like expressions, corresponding to two different electronic transitions, having similar energies but different widths. The energies and band strengths of these two transitions compare favorably with previous ab initio calculations. The cross sections of ClOOCl at wavelengths longer than 300 nm are significantly lower than all previous measurements or estimates. These low cross sections in the photolytically active region of the solar spectrum result in a rate of photolysis of ClOOCl in the stratosphere that is much lower than currently recommended. For conditions representative of the polar vortex (solar zenith angle of 86o, 20 km altitude, and O3 and temperature profiles measured in March 2000) calculated photolysis rates are a factor of 6 lower than the current JPL/NASA recommendation. This large discrepancy calls into question the completeness of present atmospheric models of polar ozone depletion.
127643. Robbo the Yobbo at 06:44 AM on 29 July 2009
        Climate time lag
        vChris You are avoiding the essential points - and indulging in the usual absurd and peripheral ad hominem arguments. If Pope et el were wrong in their cross-section measurement - I will check it out it is not the end of the Earth. I will go back to this topic as I obviously missed the April 2009 paper. Damned how could that happen? Speculation on 55 million year old rocks may be fun but very uncertain and not immediately applicable to contemporary issues. No comment on the new Svensmark paper, Clement et al, Trenberth and Fasula? This is not uncertainty – but certainty about the additional and probably related mechanisms – decadal SST changes, cloud changes, significant additional shortwave forcing in the most recent period of warming between 1976 and 1998, lees shortwave forcing since and what was always a reasonable connection of cosmic rays to clouds. The latter reinforced yet again in a different and quite elegant observational approach to the subject. So now we have theoretical, statistical, experimental and observational support. And this is the planetary reality – no warming in the oceans and the atmosphere (the heat content for the system) for 10 years. The probability of no warming for another decade or two as the decadal pattern of changes in SST and clouds continue. Yes I could be wrong along with thousands of other scientists – but the planet keeps telling me I am right. I have had enough of the juvenile insults. Goodbye Chris. Robbo
127644. chris at 02:26 AM on 29 July 2009
        Climate time lag
        well yes thingadonta, we can all look back into the depths of the barely imaginable past with great satisfaction, since whatever the contingent happenings, nasty or nice, their progression lead directly to each and every one of us existing now (even the irredeemably naughty Robbo). However that shouldn't lead us to believe that we (or our near descendants) are bound to sail through major climate perturbations with happy faces, since our societies may very well adapt poorly to changes that might arise. After all during major extinction events, life can be hard and species do go extinct. I doubt that humankind is seriously in danger of terminal decline, but major climate change will likely provide severe strains on our societies, and things are likely to be tough to decidedly unpleasant. Of course we could look back at the dinosaurs for comfort and observe that they sailed merrily through (apparently) major climate swings involving atmospheric CO2 concentrations ranging from (apparently) as high as 5000 ppm (hot-hot) to (apparently) as low as 500 ppm (chilly-chilly). However that is to compress geological time to human proportions. In reality these climate changes (as far as we can tell) occurred over many 100's of 1000's and millions of years, and individual dinosaur species migrated, adapted, evolved, became extinct through these vast periods. The fact that some dinosaur species thrived in a hot world nearly 200 million years ago is not a good marketing ploy for a suddenly hot contemporary world.
127645. AreaMan at 23:36 PM on 28 July 2009
        Climate time lag
        Where does the heat "Hide" during the time lag? We all know it can't really hide, something has to get warm or change phase or something...
        Response: The heat doesn't hide, this is the kind of misconception I was hoping to clear up in this post (perhaps to my discredit, I didn't explain clearly enough). What happens if the planet is in radiative imbalance with more energy coming in than going out? Then the planet is accumulating heat and begins to warm. Note - it immediately starts warming - the heat doesn't disappear for a few decades. But the heating is gradual because of the thermal inertia of the oceans - it takes a while for the oceans to warm up. Like turning on a kettle - the water doesn't boil immediately but takes a while to warm up.
        
        As the planet's temperature rises, the amount of energy radiated back out to space increases. Eventually the energy radiated out equals the energy coming in. At that point, the planet is back in radiative equilibrium and stops warming. The climate time lag is the time it takes for the planet to get back to equilibrium.
127646. AreaMan at 23:23 PM on 28 July 2009
        What causes short term changes in ocean heat?
        "Global heat also fell during this time, but somewhat less so, suggesting that some of the tropical heat may have been exported to higher latitudes. You are mangling the English language, and destroying logic. You aren't writing what you mean. The higher latitudes are part of the globe. If heat left one part of the globe and trotted up to the higher latitudes, the globe got neither warmer nor cooler. This sort of basic confusion mangles all sorts of reports on all sides of the debate. Be more careful. The Primary effect of any ENSO event is to simply move heat around. Secondary effects may change the energy balance by altering the IR radiation from the earth. For example, by altering clouds. I think we can agree ENSO does not alter solar brightness. Moving heat around can, by itself, change air temps, but that is not global warming or cooling.
127647. thingadonta at 22:26 PM on 28 July 2009
        Climate time lag
        I like the idea that the Jurassic Dinosaurs ran around eating each other, diversifying, evolving and generally thriving when C02 was up to 5000ppm; illustrates Michael Crichton's global warming position rather nicely I suspect. As for PETM, there was a similar explosion of diversity around the PETM 55Ma event in mammals wasn't there? Love that C02 biodiversity!
127648. chris at 22:13 PM on 28 July 2009
        Climate time lag
        Robbo, you've provided yet another example of my statement about the mis-use of glorious scientific uncertainty in peripheral elements of scientific knowledge, as a blunderbuss to cast doubt on rather well-established science. let's look at your dichlorine peroxide assertion in the light of my statement about uncertainty, which I reproduce below:

        Sadly, the tedious pretence that uncertainty over second-order (and often rather peripheral) elements of phenomena somehow constitutes cause for doubting the essential elements of our understanding is creepy, but perhaps it was ever thus where science impacts on politics and vested-interest!

        You stated: "In 2007, chemists at NASA’s JPL remeasured the photolysis rate of dichlorine peroxide at almost 1/10th of what was required to explain ozone depletion." Note that this observation never cast much serious doubt on our understanding of the role of CFC's in stratospheric ozone depletion (for example empirical atmospheric measures of oxygenated chlorinated species like ClO/ClOOCl were always incompatible with the laboratory analyses of Pope et al from NASA JPL). Normally, where there is some uncertainty, we sit back and wait to see how things develop, before charging in and asserting that the uncertainty fundamentally undermines our knowledge and understanding. Now that we've sat back and waited, we find that the uncertainty has resolved iself in favour of empirical observations and our previous understanding [*]. The experimental artefacts that bedevilled Pope et al's studies (extreme difficulty of preparing pure chlorine peroxide) have been solved by using a mass spectrometry fractionation method, and reanalysis of pure samples shows that the photolysis rates of ClOOCl are in fact in line with the standard photochemical models of ozone depletion. It's always worth relaxing about uncertainty; charging in with premature insinuations that our understandings are fundamentally flawed based on wildly cherrypicked interpretations of provisional analyses, is tedious, and reflects poor standards of scientific nous in those that are prone to those sorts of scientific misrepresentation. [*] Chen HY (2009) "UV Absorption Cross Sections of ClOOCl Are Consistent with Ozone Degradation Models "Science 324, 781-784 Abstract: Recently, discrepancies in laboratory measurements of chlorine peroxide (ClOOCl) absorption cross sections have cast doubt on the validity of current photochemical models for stratospheric ozone degradation. Whereas previous ClOOCl absorption measurements all suffered from uncertainties due to absorption by impurities, we demonstrate here a method that uses mass-selected detection to circumvent such interference. The cross sections of ClOOCl were determined at two critical wavelengths (351 and 308 nanometers). Our results are sufficient to resolve the controversial issue originating from the ClOOCl laboratory cross sections and suggest that the highest laboratory estimates for atmospheric photolysis rates of ClOOCl, which best explain the field measurements via current chemical models, are reasonable."
127649. thingadonta at 21:59 PM on 28 July 2009
        A Great Science Fiction Writer Passes - Goodbye Dr. Crichton
        When is the movie of 'State of Fear' coming out?. The references at the end are a useful guide also.
127650. chris at 21:36 PM on 28 July 2009
        Climate time lag
        re #263 You've got that wrong I think, Robbo. Have a more careful read of the Zeebe paper. These authors used paleorecords to constrain the initial carbon pulse which derived from CO2 and/or methane (which would have been quickly oxidised to CO2). This was limited (according to their analysis) to 3000 Pg of carbon or less, and (depending on the pre-existing atmospheric CO2 background) would have raised the atmospheric CO2 levels to around 1700 ppm. The authors conclude that additional feedbacks/forcings are required to yield the temperature rise estimates determined independently. These include the release of additional warming-induced greenhouse gases including methane. Since the authors state this explicitly, it's difficult to argue that they don't include this as a possible origin of additional forcing:

        Possible causes of the excess warming include increased production and levels of trace greenhouse gases as a consequence of the climatic warming (such as CH4; ref. 28).

        CH4 is methane Likewise David Beerling in his accompanying report to this paper in the same issue states (concerning the origin of feedbacks/amplification):

        Possible alternative candidates include methane emissions from swamplands6, 7 and permafrost8, and increases in atmospheric moisture9, biogenic aerosols and cloudiness10.

        Incidentally, there is a certain surreal element to this discussion (as most of the discussions on this thread). There is very little controversy that the PETM warming was driven by massive release of greenhouse gases into the atmosphere with subsequent warming, ocean acidification and some rather significant marine extinctions. On top of this fairly fundamental understanding there is some uncertainty about the details (such as we're discussing), not surprising since these 55 MYA phenomena are represented as paleoproxy traces in marine sediments and such-like. On this uncertainty, the Zeebe paper is rather concerning, since it indicates that the earth temperature response to very large greenhouse gas emissions may be amplified by feedbacks that are not generally considered in the standard estimation of climate sensitivity based on known short term feedbacks. Returning to uncertainty in science, most scientists would agree that uncertainty is great, since it provides an impetus for experimentation/observation and further understanding and refinement of our knowledge. Sadly, the tedious pretence that uncertainty over second-order (and often rather peripheral) elements of phenomena somehow constitutes cause for doubting the essential elements of our understanding is creepy, but perhaps it was ever thus where science impacts on politics and vested-interest!

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