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Comments 127651 to 127700:

127651. chris at 10:44 AM on 28 July 2009
        Climate time lag
        Yes, that's an interesting article. Using the range of climate sensitivities currently available for fast response to raised atmospheric CO2 levels near 3 oC (+/- about 1.5 oC at 95% certainty) the estimated amount of CO2 added to the atmosphere during the PETM is expected to have caused only up to 3.5 oC of warming. Independent paleotemperature data indicates that tropical oceans warmed by 4-6 oC, and high latitude oceans by 5-8 oC. So within our current understanding of climate sensitivity, the PETM warming, if correct, is too large to be explained by current estimates of climate sensitivity to CO2 (assuming Zachos' estimates of [CO2] are about right). The authors consider that additional feedbacks amplified the CO2 (and methane) warming. Possible contributions include methane emissions from permafrost or swamplands, or enhanced water vapour [*]. As the authors describe, the entire PETM episode was very long (around 75,000 years), and a concern for our present understanding is that climate sensitivities determined taking into account relatively rapid feedbacks (the Charney sensitivity) don't accommodate longe term positive feedbacks (like large scale methane release induced by CO2-induced ramping up of temperature), that might enhance the earth's temperature sensitivity to CO2 (possibly after a certain threshold temperature rise is reached). The essential understanding of the PETM being triggered by massive release of greenhouse gases (CO2 and/or methane) likely associated with tectonic events involving opening up of the nascant plate boundary in the (now) N. Atlantic (see Storey 2007 abstract in my post just above), isn't affected by this article. [*] R. D. Pancost et. al. (2007) "Increased terrestrial methane cycling at the Palaeocene–Eocene thermal maximum" Nature 449, 332-335 abstract: The Palaeocene–Eocene thermal maximum (PETM), a period of intense, global warming about 55 million years ago1, has been attributed to a rapid rise in greenhouse gas levels, with dissociation of methane hydrates being the most commonly invoked explanation2. It has been suggested previously that high-latitude methane emissions from terrestrial environments could have enhanced the warming effect3, 4, but direct evidence for an increased methane flux from wetlands is lacking. The Cobham Lignite, a recently characterized expanded lacustrine/mire deposit in England, spans the onset of the PETM5 and therefore provides an opportunity to examine the biogeochemical response of wetland-type ecosystems at that time. Here we report the occurrence of hopanoids, biomarkers derived from bacteria, in the mire sediments from Cobham. We measure a decrease in the carbon isotope values of the hopanoids at the onset of the PETM interval, which suggests an increase in the methanotroph population. We propose that this reflects an increase in methane production potentially driven by changes to a warmer1, 6 and wetter climate7, 8. Our data suggest that the release of methane from the terrestrial biosphere increased and possibly acted as a positive feedback mechanism to global warming.
127652. thingadonta at 10:41 AM on 28 July 2009
        Climate time lag
        re 258: Robbo Yes, thats the PETM paper I was talking about.
127653. thingadonta at 10:32 AM on 28 July 2009
        Climate time lag
        re:257 Chris A few points, (even though this isnt climate time lag): "These extremely large changes are incompatible with temperature-driven re-equilibration of CO2 into the atmosphere which rather strong evidence indicates can only really yield CO2 changes of around 200 ppm over the full range of Phanerozoic temperatures". Yes, most of the c02 rise was driven by increased volcanism especially in the Jurassic, but the earth thrived throughout most of the times these c02 values were high in Jurassic-Cretaceous. Solar output was not much different than now, and values of 5000ppm C02 in Jurassic did not create runaway greenhouse etc. The general issue is: how much did changes in ocean currents, continental configurations, very strong volcanism, naturally driven T changes, lower solar output back then etc, actually interact with c02 /climate sensivity in all this? I suspect the models/explanations are 'tweaked', but it does require more reading from me. Because of volatile volcanism (those dinosaur movies were right-there was much more volcanism back then), the c02 variations in response to volcanism, T and tectonic changes, were also much more profound than "just 200ppm". But all this doesn't say much about strong or weak c02 sensitivity. But one crude skeptical point is that the world didnt end when Co2 values were much much higher. The very widesread basaltic volcanism in eg the Triassic-to especially the Jurassic (we have widespread Jurassic volcanics through NSW, Victoria, Tasmania, extending right through to Antarctica, South America, South Africa due to large-scale continental Gondwana breakup) caused the values of c02 to rise up to 5000ppm. The only major extinction event here was the end Triassic, associated with this break up. C02 levels remained much higher from this volcanism and ongoing continental configuration with no runaway greenhouse, with thriving organisms and a solar output not much different han now. The PETM event requires more reading from me. But I note that a recent blog/paper on 'Watts up with that website' questions the whole relative effect of c02/CH4 on this major event. My general concern is being able to quantify the relative contribution of c02/greenhouse gases in these geological ages and events without researcher's bias, and general climate sensitivity to c02, back then and now. You say there is 'abundant literature', but there is abundant literature on recent climate now without definitive/agreement on climate c02 sensitivity-people are still not sure about it. I doubt they can be that sure about the geological past as well, other than 'no end of the world'. The PETM event requires reading from me. The issue of 'suddenness' in the earth-climate c02 etc relationship is what the alarmists are all worried about with respect to recent human effects. I enjoy reading your abstracts, its been a while since I looked at some of these. I especially remember looking at the coals in NSW which simply 'disappear' at the end Permian, and not reappear for 10 Ma-organisms all dead!. Also the Triassic red sandstones and Jurassic volcanics-these were worldwide features. But I didnt know that c02 was so high then, makes sense with all the volcanism. By the way, there is evidence in the end Ordovician-early Silurian in Australia for major tectonism.
127654. Robbo the Yobbo at 09:40 AM on 28 July 2009
        Climate time lag
        Nature Geoscience Published online: 13 July 2009 | doi:10.1038/ngeo578 Carbon dioxide forcing alone insufficient to explain Palaeocene–Eocene Thermal Maximum warming Richard E. Zeebe1, James C. Zachos2 & Gerald R. Dickens3 ‘The Palaeocene–Eocene Thermal Maximum (about 55 Myr ago) represents a possible analogue for the future and thus may provide insight into climate system sensitivity and feedbacks1, 2. The key feature of this event is the release of a large mass of 13C-depleted carbon into the carbon reservoirs at the Earth's surface, although the source remains an open issue3, 4. Concurrently, global surface temperatures rose by 5–9 °C within a few thousand years5, 6, 7, 8, 9. Here we use published palaeorecords of deep-sea carbonate dissolution10, 11, 12, 13, 14 and stable carbon isotope composition10, 15, 16, 17 along with a carbon cycle model to constrain the initial carbon pulse to a magnitude of 3000 Pg C or less, with an isotope composition lighter than -50. As a result, atmospheric carbon dioxide concentrations increased during the main event by less than about 70% compared with pre-event levels. At accepted values for the climate sensitivity to a doubling of the atmospheric CO2 concentration1, this rise in CO2 can explain only between 1 and 3.5 °C of the warming inferred from proxy records. We conclude that in addition to direct CO2 forcing, other processes and/or feedbacks that are hitherto unknown must have caused a substantial portion of the warming during the Palaeocene–Eocene Thermal Maximum. Once these processes have been identified, their potential effect on future climate change needs to be taken into account.’
127655. chris at 07:42 AM on 28 July 2009
        Climate time lag
        That doesn't really accord with the evidence 'though thingadonta. For example, we can determine from the glacial record the response of CO2 levels to earth temperature variation. It's likely that the transitions are slow enough (~ 5000 years) for the atmospheric CO2 changes to come to near equilibrium with the temperature changes. So around 5 oC of warming/cooling (glacial/interglacial) gives around 90-100 ppm of atmospheric CO2 change (around 180 ppm glacial/around 270 ppm interglacial through a number of glacial cycles). This gives approx 20 ppm of atmospheric CO2 change per oC of global-scale warming/cooling from the geophysical response of CO2 ocean/atmosphere partitioning (and any other contributions like biological responses; terrestrial sequestering) to temperature. That is inconsistent with the very large CO2 variations observed in the Phanerozoic record: 3000 ppm atmospheric CO2 in the Devonian to 1000 ppm in the early Carboniferous to values down to 500 ppm preceding and during the mid Carboniferous and early Permian glacials back up to 1000 -1500 ppm in the late Permian; up to 2000 ppm in the Triassic; the Jurassic has values apparently as high as 4000-5000 ppm and then reduced CO2 to values near 500-1000 ppm during cold Jurassic periods….and so on. These extremely large changes are incompatible with temperature-driven re-equilibration of CO2 into the atmosphere which rather strong evidence indicates can only really yield CO2 changes of around 200 ppm over the full range of Phanerozoic temperatures. Likewise it's perverse to attribute very large increases of CO2 that are known to be contemporaneous with major catastrophic tectonic processes, to temperature responses that we know cannot possibly have produced such massive changes in CO2. For example the Paleo-Eocene Thermal Maximum (PETM) 55 MYA is clearly associated temporally with the massive tectonic processes involved in opening up of the N. Atlantic as the plates separated above a mantle plume, and which resulted in massive enhancement of atmospheric greenhouse gases (not to mention ocean acidification etc.) [*]. It would require some rather bottom-squirming dissembling to argue away this evidence, and one could raise further examples of catastrophically raised CO2 levels associated with some of the other major extinctions in Earth history (see [**] below). The fact that we don't know what caused any particular event (.g. why did the Serbian or Deccan Traps erupt just when they did?) is not really an argument against this very basic causality in relation to variations in greenhouse gas concentrations. After all we know that the loss of heat from the Earth's interior results in plate movement with ocean subduction, mantle plume formation and such like. We can assume that the process is essentially stochastic, and that occasionally continents collide (Africa into Europe; India into S. Asia), and mantle plumes breach the surface with massive flood basalt extrusion (e.g. Deccan Traps – I've seen smaller versions of these flood basalt landscapes in the West of Scotland). We can understand how biologic processes may result in large scale slow reduction of greenhouse gases (oxygen-producing organisms in the Archaean; plant evolution that gave rise to drawdown of CO2 and glaciation in the Carboniferous)….we understand the processes involved in weathering and their temperature dependences…and so on. As you indicate the location of the land masses is important (over the poles promotes ice build up; near the equator promotes weathering). There is such a truly vast scientific knowledge of these processes and their interrelationships, it doesn't seem reasonable to ignore this and propose that completely uncharacterised putative temperature swings of which there is neither evidence nor cause resulted in the extremely large atmospheric CO2 variations that we know cannot have been temperature-driven anyway! In my opinion we really have to follow the evidence. And interpretations based on the evidence is always much more interesting and satisfying than those involving attempted forcing of dodgy hypothesis into empirical scenarios that they just don't fit. Incidentally, I think you're right about the lack of really sound evidence for bolide impacts as recurring causal elements of extinctions. However these (extinctions) do seem to associate with major tectonic events [**] [*] M. Storey et al. (2007)Paleocene-Eocene Thermal Maximum and the Opening of the Northeast Atlantic Science 316, 587 - 589 abstract: The Paleocene-Eocene thermal maximum (PETM) has been attributed to a sudden release of carbon dioxide and/or methane. 40Ar/39Ar age determinations show that the Danish Ash-17 deposit, which overlies the PETM by about 450,000 years in the Atlantic, and the Skraenterne Formation Tuff, representing the end of 1 ± 0.5 million years of massive volcanism in East Greenland, are coeval. The relative age of Danish Ash-17 thus places the PETM onset after the beginning of massive flood basalt volcanism at 56.1 ± 0.4 million years ago but within error of the estimated continental breakup time of 55.5 ± 0.3 million years ago, marked by the eruption of mid-ocean ridge basalt–like flows. These correlations support the view that the PETM was triggered by greenhouse gas release during magma interaction with basin-filling carbon-rich sedimentary rocks proximal to the embryonic plate boundary between Greenland and Europe. [**] Wignall P (2005) The link between large igneous province eruptions and mass extinctions Elements 1, 293-297 Abstract: In the past 300 million years, there has been a near-perfect association between extinction events and the eruption of large igneous provinces, but proving the nature of the causal links is far from resolved. The associated environmental changes often include global warming and the development of widespread oxygen-poor conditions in the oceans. This implicates a role for volcanic CO2 emissions, but other perturbations of the global carbon cycle, such as release of methane from gas hydrate reservoirs or shut-down of photosynthesis in the oceans, are probably required to achieve severe green-house warming. The best links between extinction and eruption are seen in the interval from 300 to 150 Ma. With the exception of the Deccan Trap eruptions (65 Ma), the emplacement of younger volcanic provinces has been generally associated with significant environmental changes but little or no increase in extinction rates above background levels. R. J. Twitchett (2006) The palaeoclimatology, palaeoecology and palaeoenvironmental analysis of mass extinction events Palaeogeog., Palaeoclimatol., Palaeoecol. 232, 190-213 concluding paragraph: "Mass extinction studies have enjoyed a surge in scientific interest of the past 30 years that shows no sign of abating. Recent areas of particular interest include the palaeoecological study of biotic crises, and analyses of patterns of post-extinction recovery. There is good evidence of rapid climate change affecting all of the major extinction events, while the ability of extraterrestrial impact to cause extinction remains debatable. There is growing evidence that food shortage and suppression of primary productivity, lasting several hundred thousand years, may be a proximate cause of many past extinction events. Selective extinction of suspension feeders and the prevalence of dwarfed organisms in the aftermath are palaeoecological consequences of these changes. The association with rapid global warming shows that study of mass extinction events is not just an esoteric intellectual exercise, but may have implications for the present day." Keller G (2005) Impacts, volcanism and mass extinction: random coincidence or cause and effect? Austral. J. Earth Sci 52 725-757. Abstract: Large impacts are credited with the most devastating mass extinctions in Earth's history and the Cretaceous - Tertiary (K/T) boundary impact is the strongest and sole direct support for this view. A review of the five largest Phanerozoic mass extinctions provides no support that impacts with craters up to 180 km in diameter caused significant species extinctions. This includes the 170 km-diameter Chicxulub impact crater regarded as 0.3 million years older than the K/T mass extinction. A second, larger impact event may have been the ultimate cause of this mass extinction, as suggested by a global iridium anomaly at the K/T boundary, but no crater has been found to date. The current crater database suggests that multiple impacts, for example comet showers, were the norm, rather than the exception, during the Late Eocene, K/T transition, latest Triassic and the Devonian-Carboniferous transition, but did not cause significant species extinctions. Whether multiple impacts substantially contributed to greenhouse warming and associated environmental stresses is yet to be demonstrated. From the current database, it must be concluded that no known Phanerozoic impacts, including the Chicxulub impact (but excluding the K/T impact) caused mass extinctions or even significant. species extinctions. The K/T mass extinction may have been caused by the coincidence of a very large impact ( > 250 km) upon a highly stressed biotic environment as a result of volcanism. The consistent association of large magmatic provinces (large igneous provinces and continental flood-basalt provinces) with all but one (end-Ordovician) of the five major Phanerozoic mass extinctions suggests that volcanism played a major role. Faunal and geochemical evidence from the end-Permian, end-Devonian, end-Cretaceous and Triassic/Jurassic transition suggests that the biotic stress was due to a lethal combination of tectonically induced hydrothermal and volcanic processes, leading to eutrophication in the oceans, global warming, sea-level transgression and ocean anoxia. It must be concluded that major magmatic events and their long-term environmental consequences are major contributors, though not the sole causes of mass extinctions. Sudden mass extinctions, such as at the K/T boundary, may require the coincidence of major volcanism and a very large impact .
127656. Quietman at 02:08 AM on 28 July 2009
        Climate's changed before
        Global Warming: Scientists' Best Predictions May Be Wrong ScienceDaily (July 15, 2009) No one knows exactly how much Earth's climate will warm due to carbon emissions, but a new study suggests scientists' best predictions about global warming might be incorrect. ... The study, which appears in Nature Geoscience, found that climate models explain only about half of the heating that occurred during a well-documented period of rapid global warming in Earth's ancient past. The study, which was published online July 13, contains an analysis of published records from a period of rapid climatic warming about 55 million years ago known as the Palaeocene-Eocene thermal maximum, or PETM. "In a nutshell, theoretical models cannot explain what we observe in the geological record," said oceanographer Gerald Dickens, a co-author of the study and professor of Earth science at Rice University. "There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models." http://www.sciencedaily.com/releases/2009/07/090714124956.htm Read the rest, Interesting.
127657. thingadonta at 22:55 PM on 27 July 2009
        Climate time lag
        re 255: Chris: I can't comment about the relationship between co2 and climate sensivity etc throughout geological periods without having a more detailed look at the papers and data you mention. So thanks for the papers. But I DO know that glacial periods occur where there is eg: 1) restricted ocean current circulation (eg in the last 37 Ma-Australia's increasing separation from Antartica, Africa crashing into Asia and eliminating almost the the Tethys Sea-only the small Meditterranen Sea is left, and South America joining North America in the last few million years), and 2) where continents are bound together near the poles (eg Permo-Carboniferous). The general reduction in ocean circulation causes cooling in the oceans and subsequent lowering of c02 (higher solubility), the relative effect of lowering c02 on T itself is likely small-once again I suspect the reserchers have enhanced co2's relative effect in such cases. Its a chicken and egg argument, c02 drops because the ocean and earth cools, not the other way round. I also know from experience that it can be very difficult to nail-down cause(s) of geological-age climate changes, and the sometimes associated minor/mass extinction events; the usual trend is that the latest research 'fad' usually dominates the debate- eg K-T boundary extinction event in the 1980s with bolide impact, as opposed/coupled with strong volcanism in the Deccan traps in India (very likely a combination of both). Also, I mention the end Permian with its very strong volcanism in Siberia which widespread hothouse-(but what caused the Siberian volcanism in the first place?). Note also: there are no coals in the early Triassic, coal-forming plants went extinct at end Permian for around 10Ma and had to re-evolve, but was this due to greenhouse gases?. I suspect, but I am not familiar with all this more recent geological-greenhouse gas literature, that relative greenhouse gas effects can be 'adjusted' to produce whatever effect on climate and/or extinction events in the geological past is desired to produce a preconceived outcome. This happened with bolide impacts (with few real major or minor extinction events correlated); researchers have also probably overshot the mark with greenhouse gases and the geological past, with more chicken and egg-type arguments (co2 causing T to change or T causing c02 to change). eg: "When atmospheric CO2 levels drop below thresholds, the levels of which are modulated by the solar output, cold/glacial periods result". But how do you know that T didnt drop naturally first, with the drops in ocean T leading to drops in atmospheric c02 from higher solubility of c02 in cooler oceans? And one more thing, is the geological record at sufficient resolution to resolve this? I suspect it isnt, in the vast majority of cases. I'll have to read the stuff sometime.
127658. chris at 21:15 PM on 27 July 2009
        Climate time lag
        re #249 thingadonta, there is a huge body of evidence that the climate was intimately sensitive to atmospheric greenhouse gas concentrations throughout the long history of the earth. The effect of the progressively increasing solar constant is that greenhouse gas (largely CO2 since the end of the Archaean) thresholds for various broad climate states (hot/warm - cool/cold) shift through deep time. However the climate remains highly sensitive to greenouse gas levels (obviously so, since greenhouse gases are greenhouse gases!). So analysis of CO2 levels from paleoproxies and comparison with paleotemperatures and evidence for glaciations, demonstrates a rather close connection with atmospheric CO2 levels during many hundreds of million years. The decreasing levels of atmospheric CO2 through the late Eocene are linked with the onset of first Antarctic glaciation and in the late Pliocene with the onset of Greenland glaciation [*]. However the threshold for these glaciations (around 500 ppm of atmospheric CO2) are much lower than the thresholds for glaciation in the deep past, where, for example, the very much weaker solar output during the Ordovician meant that drops of CO2 levels below around 2000-3000 were sufficient to instigate significant widespread cold and localized glaciation [**]. There is a vast scientific literature on CO2-climate links right through the entire Phanerozoic, a vast period of 500-odd million years where there is a reasonable coverage of paleotemperature and paleo-CO3 proxies. The data frm more than 100 studies has been summarized in a detailed review published in 2006 [**]. Since that time a large number of additional evidence for close CO2-earth temperature links has been published [***]. So the earth's climate has been very sensitive to atmospheric CO2 levels for many 100's of millions (if not 1000's of millions) of years. When atmospheric CO2 levels drop below thresholds, the levels of which are modulated by the solar output, cold/glacial periods result. Likewise when atmospheric CO2 levels rise (e.g. following major tectonic events, or possibly during the long slow grinding of the Indian subcontinent towards and into South Asia through the early and middle Eocene, with the release of massive amounts of CO2 from carbonate sediments), the earth is warm/hot. [*] D.L. Royer (2006) "CO2-forced climate thresholds during the Phanerozoic" Geochim. Cosmochim. Acta 70, 5665-5675. [ ***] More recent studies supplement the information in Royers compilation and cover additional periods with new data sets right through the past several hundreds of millions of years: [**] D. J. Lunt et al. (2008) Late Pliocene Greenland glaciation controlled by a decline in atmospheric CO2 levels Nature 454, 1102-1105 R.E. Carne, J.M. Eiler, J. Veizer et al (2007) "Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era" Nature 449, 198-202 W. M. Kurschner et al (2008) “The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of the terrestrial ecosystem” Proc. Natl. Acad. Sci. USA 105, 499-453. D. L. Royer (2008) “Linkages between CO2, climate, and evolution in deep time” Proc. Natl Acad. Sci. USA 105, 407-408 Zachos JC (2008) “An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics” Nature 451, 279-283. Doney SC et al (2007) “Carbon and climate system coupling on timescales from the Precambrian to the Anthropocene” Ann. Rev. Environ. Resources 32, 31-66. Horton DE et al (2007) “Orbital and CO2 forcing of late Paleozoic continental ice sheets” Geophys. Res. Lett. L19708 B. J. Fletcher et al. (2008) “Atmospheric carbon dioxide linked with Mesozoic and early Cenozoic climate change” Nature Geoscience 1, 43-48. [****] Kent DV, Muttoni G “Equatorial convergence of India and early Cenozoic climate trends” (2008) Proc. Natl. Acad. Sci. USA 105, 16065-16070. Bohaty SM et al. (2009) “Coupled greenhouse warming and deep-sea acidification in the middle Eocene”, Paleooceanography 24, art # PA2207. Robert M. DeConto et al (2008) "Thresholds for Cenozoic bipolar glaciation" Nature 455, 652-656
127659. Robbo the Yobbo at 17:44 PM on 27 July 2009
        Climate time lag
        Should be - Clement et al speculate that decreasing cloud cover...
127660. Robbo the Yobbo at 17:41 PM on 27 July 2009
        Climate time lag
        Before Chris complains about Quadrant and Lindzen - compare it with the Trenberth and Fasula (2009) study above. Increased upward IR flux balancing CO2 warming. 'Instead the main warming from an energy budget standpoint comes from increases in absorbed solar radiation that stem directly from the decreasing cloud amounts. These findings underscore the need to ascertain the credibility of the model changes, especially insofar as changes in clouds are concerned.' This is reinforced by a study in last weeks Science by Clement et al(copy available at http://www.drroyspencer.com/Clement-et-al-cloud-feedback-Science-2009.pdf) - note that the paper is the link - although Spencer. as usual, is worth reading on this. Clement et al speculate that the decreasing is a positive feedback but the periods look much more like good ol' decadal SST. Increasing cloud cover since circa 2000 is a bit of a bummer for the cloud positive feedback theory - but icreasing temperature and water vapour and decreasing cloud cover was always a bit of a stretch. It could simply be a 'chaotic dynamic' response - a climate system tuned to a 50 year cycle. But one has to wonder about a connection to the 22 year solar cycle.
127661. thingadonta at 14:25 PM on 27 July 2009
        Climate time lag
        Regarding radiative imbalances on this post, from Richard Lindzen: "It means that increases in surface temperature are accompanied by reductions in the net outgoing radiation – thus enhancing the greenhouse warming. All climate models show such changes when forced by observed surface temperatures. Satellite observations of the earth’s radiation budget allow us to determine whether such a reduction does, in fact, accompany increases in surface temperature in nature. As it turns out, the satellite data from the ERBE instrument (Barkstrom, 1984, Wong et al, 2006) shows that the feedback in nature is strongly negative -- strongly reducing the direct effect of CO2 (Lindzen and Choi, 2009) in profound contrast to the model behavior. This analysis makes clear that even when all models agree, they can all be wrong, and that this is the situation for the all important question of climate sensitivity". http://www.quadrant.org.au/blogs/doomed-planet/2009/07/resisting-climate-hysteria
127662. Robbo the Yobbo at 14:13 PM on 27 July 2009
        Climate time lag
        There is a 'cute' little carbon cycle diagram. http://en.wikipedia.org/wiki/Carbon_cycle Ice ages seem to be the result of factors which trigger ice sheet growth. In the pre-Quaternary - these influences included continental drift and tectonic uplift. Some of these studies that Chris is referencing suggest that the ice extent was sufficient to prevent warming even with high concentrations of CO2 in the atmosphere. In the Quaternary - it appears that orbital eccentricities have been sufficient to trigger ice sheet growth, a strong albedo feedback, and rapid cooling. Hence the 100,000 year cycles. ‘Carbon is released into the atmosphere in several ways: • Through the respiration performed by plants and animals. This is an exothermic reaction and it involves the breaking down of glucose (or other organic molecules) into carbon dioxide and water. • Through the decay of animal and plant matter. Fungi and bacteria break down the carbon compounds in dead animals and plants and convert the carbon to carbon dioxide if oxygen is present, or methane if not. • Through combustion of organic material which oxidizes the carbon it contains, producing carbon dioxide (and other things, like water vapour). Burning fossil fuels such as coal, petroleum products, and natural gas releases carbon that has been stored in the geosphere for millions of years. Burning agrofuels also releases carbon dioxide. • Production of cement. Carbon dioxide is released when limestone (calcium carbonate) is heated to produce lime (calcium oxide), a component of cement. • At the surface of the oceans where the water becomes warmer, dissolved carbon dioxide is released back into the atmosphere. • Volcanic eruptions and metamorphism release gases into the atmosphere. Volcanic gases are primarily water vapour, carbon dioxide and sulphur dioxide. The carbon dioxide released is roughly equal to the amount removed by silicate weathering; so the two processes, which are the chemical reverse of each other, sum to roughly zero, and do not affect the level of atmospheric carbon dioxide on time scales of less than about 100,000 years.’ The longer term changes in CO2 are the result of biological processes and these are mediated by temperature. The higher the temperature, within reason, the higher the biological activity – so that rising CO2 after ice ages is a symptom of rising temperatures rather than an initial cause. This doesn’t say anything about CO2 as a greenhouse gas. CO2 should reinforce warming from orbital changes and the resulting reduction in ice albedo – but anyone who claims to know what the relative effects are has rocks in their head.
127663. Robbo the Yobbo at 11:39 AM on 27 July 2009
        Climate time lag
        re 248 Tamino - not the hero of the Magic Flute - but an anonymous blogger you claim as an authority on statistics and who has many peer reviewed studies to his name - according to your misleadsing claims? Please. Your confusing me with someone else - I don't know who Weart and Ramsthorf are. You are also confusing me with someone else - someone who cares.
127664. thingadonta at 11:23 AM on 27 July 2009
        Climate time lag
        re 240 Thanks Chris: at least somebody posts intelligently. I read a few of the papers on c02 and glacial cycles and I'm still not convincd that they arent 'reaching', and trying to insert c02 effects that arent there. Certainly Flannnery does, whenever and wherever possible. In his entire book the weathermakers, he only mentions the sun 3 times, and only in denigration/passing. What lack of respect to that which has sustained him all his years. If c02 contributes 2 of 5 C to glaical warming, then the earth in glacial cycles only drops ~3C from earth-solar relationships. This should be easily modelled, although other forcings (such as cloud cover changes and importantly, ice albedo) would make it, as usual, non-definitive. Ice albedo would be very large towards the end of glacial ice ages with max ice extent, which should give a sharp rise in T once this thinning ice finally dissipates over northern zones-which may partly explain the rapid rise in T compared to slow lowering of T in glacial cycles? As for the phanerozoic, I dont think that the increase in solar output alone is enough to explain the very low sensitivity to c02 in geological times. One cant just say 'it didnt apply then', but 'it strongly applies now' without seeming to be inconsistent and selective. You mention 'Gaia', but I am of the opinion that Gaia likes things with more c02, which is why we are burning more c02 (!), -to return to several thousand ppm C02 would do planet earth good, I feel, and also I am very skeptical that a few hundred more ppm c02 in the atmosphere is anyway toxic to 'Gaia' and life on earth generally. I just dont think the earth is that sensitive to trace c02 atmospheric changes, with the geological past high co2 and associated high biodiversity as evidence.
127665. Robbo the Yobbo at 11:14 AM on 27 July 2009
        Climate time lag
        More science...from IPCC contributors...hope you find it amusing Phillipe 'Global warming due to increasing absorbed solar radiation Kevin E. Trenberth National Center for Atmospheric Research, Boulder, Colorado, USA John T. Fasullo National Center for Atmospheric Research, Boulder, Colorado, USA Global climate models used in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) are examined for the top‐of‐atmosphere radiation changes as carbon dioxide and other greenhouse gases build up from 1950 to 2100. There is an increase in net radiation absorbed, but not in ways commonly assumed. While there is a large increase in the greenhouse effect from increasing greenhouse gases and water vapor (as a feedback), this is offset to a large degree by a decreasing greenhouse effect from reducing cloud cover and increasing radiative emissions from higher temperatures. Instead the main warming from an energy budget standpoint comes from increases in absorbed solar radiation that stem directly from the decreasing cloud amounts. These findings underscore the need to ascertain the credibility of the model changes, especially insofar as changes in clouds are concerned.'
127666. Philippe Chantreau at 10:30 AM on 27 July 2009
        Climate time lag
        The ad-hom was yours, directed against Tamino. There is no discussion of the science possible with you. All you do is make barrage of arguments with a compilation of papers that you think support them. You cited Weart and Ramsthorf about D-O and Bond events suggesting that their work on natural variability was being suppressed by the climate science community. Anyone familiar with these authors knows that's nonsense. I am not going to go back to every single argument and every single paper you cited to analyze whether it is relevant and the papers actually supports your argument and to determine if that paper led to anything interesting about the big picture. Perhaps that's all you have to do but I don't have that kind of time. If I have to choose between doing something interesting and arguing with you, the choice is made in advance.
127667. Thumb at 10:29 AM on 27 July 2009
        Climate time lag
        "Why don't you get a job as a prosecutor for some totalitarian communist country? Your tendancy to make false accusations to support an ingrained bureaucratic ideology would go down well." Good example of projecting.
127668. Robbo the Yobbo at 08:59 AM on 27 July 2009
        Climate time lag
        Back to time lag? ENSO has such a dominant influence on global mean temperature that it is difficult to imagine that the decadal mode of variation has no impact on decadal surface temperature. It is trivial to compare the most recent shifts in global temperature in the mid 1040’s, the mid 1970’s and post 1998 to the phases of the PDO. It leads naturally to the suspicion that the current hiatus in warming may not be as short lived as many people hope. We are far from understanding the basis of the PDO or of predicting ENSO with more than average accuracy past three months. Next to nothing is known about the fine detail of ENSO radiaive tansfers. Swanson and Tsonis are physicists who think in terms of ‘choatic dynamical systems’ – and this covers a multitude of factors of radiative balances and ocean dynamics that are evidently barely understood. So it may be premature to calculate a‘heat lag’ if the most significant variant is so little understood. Verdon and Franks (2006) used ‘proxy climate records derived from paleoclimate data to investigate the long-term behaviour of the Pacific Decadal Oscillation (PDO) and the El Niño Southern Oscillation (ENSO). During the past 400 years, climate shifts associated with changes in the PDO are shown to have occurred with a similar frequency to those documented in the 20th Century. Importantly, phase changes in the PDO have a propensity to coincide with changes in the relative frequency of ENSO events, where the positive phase of the PDO is associated with an enhanced frequency of El Niño events, while the negative phase is shown to be more favourable for the development of La Niña events.’ Verdon, D. and Franks, S. (2006), Long-term behaviour of ENSO: Interactions with the PDO over the past 400 years inferred from paleoclimate records, Geophysical Research Letters 33: 10.1029/2005GL025052.
127669. Robbo the Yobbo at 06:56 AM on 27 July 2009
        Climate time lag
        “The close relationship between ENSO and global temperature, as described in the paper, leaves little room for any warming driven by human carbon dioxide emissions. The available data indicate that future global temperatures will continue to change primarily in response to ENSO cycling, volcanic activity and solar changes.” The Swanson and other papers I have referred here show the dominance of decadal sea surface temperature changes – particularly that associated with the PDO and decadal modulation of ENSO. These are a particularly goog introduction. Interdecadal variability and climate change in the eastern tropical Pacific: A review Alberto M. Mestas-Nun˜ez, Arthur J. Miller The Significance of the 1976 Pacific Climate Shift in the Climatology of Alaska Brian Hartmann and Gerd Wendler The best Phillipe can do is a series of insults and deceptive claims about the authority of an anonymous bogger - “Tamino is an authority on time series analysis”. Did he understand the nature of an ad hominem argument? It is simply as argument against the person rather than on the subject of the argument. Even if it is true that I am an idiot – it is still ad hominem argument. There is a need to step back and take in the whole picture rather than raise one irrelevant point after another. Carbonic snow, Tamino is an expert if you understand it or not, no trends, diurnal variation – yes it has been said – tedious variations on a theme with no rhyme or reason other than to attempt to discredit the opposition and avoid the real point. Here is another paper. http://meteora.ucsd.edu/papers/auad/Global_Warm_ENSO.pdf As I say, the proof is in the reality of global temperature. My favourite quote from Swanson is that ‘the nature of these past shifts in climate state suggests the possibility of near constant temperature lasting a decade or more into the future must at least be entertained. The apparent lack of a proximate cause behind the halt in warming post 2001/02 challenges our understanding of the climate system, specifically the physical reasoning and causal links between longer time-scale modes of internal climate variability and the impact of such modes upon global temperature.’
127670. Robbo the Yobbo at 06:54 AM on 27 July 2009
        Climate time lag
        “The close relationship between ENSO and global temperature, as described in the paper, leaves little room for any warming driven by human carbon dioxide emissions. The available data indicate that future global temperatures will continue to change primarily in response to ENSO cycling, volcanic activity and solar changes.” The Swanson and other papers I have referred here show the dominance of intersnnual and decadal sea surface temperature changes on temperature variance – particularly that associated with the PDO and decadal modulation of ENSO. The best Phillipe can do is a series of insults and deceptive claims about the authority of an anonymous bogger - “Tamino is an authority on time series analysis”. Did he the nature of an ad hominem argument? It is simply as argument against the person rather than on the subject of the argument. Even if it is true that I am an idiot – it is still ad hominem argument. Interdecadal variability and climate change in the eastern tropical Pacific: A review Alberto M. Mestas-Nun˜ez, Arthur J. Miller The Significance of the 1976 Pacific Climate Shift in the Climatology of Alaska Brian Hartmann and Gerd Wendler Here is another one. There is a need to step back and take in the whole picture rather than raise one irrelevant point after another. Carbonic snow, Tamino is an expert wheteher you understand it or not, no trends, diurnal variation – yes it has been said – tedious variations on a theme with no rhyme or reason other than to attempt to discredit the opposition and avoid the real point. Dishonest and intended to mislead. Here is another paper. http://meteora.ucsd.edu/papers/auad/Global_Warm_ENSO.pdf As I say, the proof is in the reality of global temperature. My favourite quote from Swanson is that ‘the nature of these past shifts in climate state suggests the possibility of near constant temperature lasting a decade or more into the future must at least be entertained. The apparent lack of a proximate cause behind the halt in warming post 2001/02 challenges our understanding of the climate system, specifically the physical reasoning and causal links between longer time-scale modes of internal climate variability and the impact of such modes upon global temperature.’
127671. Robbo the Yobbo at 05:32 AM on 27 July 2009
        Climate time lag
        No answer for your silly and deceptive Tamino claim? No discussion of science. More ad hominen argument. No I thought you were 14 from the imaturity of the you expression.
127672. Flipper at 03:34 AM on 27 July 2009
        Other planets are warming
        I am curious, With the millions of dollars of equipment we left on the moon 40 years ago, did anyone leave a thermometer? Has there been trends? Remote mensurements would not be able to provide reliable data, as the technology used has changed and become much more precise in the past 40 years. The Moon has no atsmosphere so only the surface temperature based upon the direct influence of the Sun would be recorded (I know there is a very slight atmosphere and there is slight internal heating but this should suffice as a baseline to compare the planets to) There have been arguments that ground based weather stations can;t be reliable over a long period of time due to micro climate influences. Measuring stations near a grassy field 50 years ago may be a strip mall now. Before we commit billions of dollars in change. We should at least disprove the Sun's influence. Anything that could melt IceCaps on Mars should have a noticable difference on our own Moon
127673. Philippe Chantreau at 03:16 AM on 27 July 2009
        Climate time lag
        Yobbo, your reading comprehension is a problem. Read again my theoretical example of an ad-hom and see how well it fits your own definition. If you can't, there is nothing anyone can do for you. The paper you linked, however, is a great example of non-sequitur. The mathematical treatment applied to the data effectively removes any trend, therefore this conclusion statement perfectly corresponds to your definition of a non-sequitur: "this study has shown that natural climate forcing associated with ENSO is a major contributor to variability and perhaps recent trends in global temperature, ..." Regardless how timid and parenthetical the perhaps makes it, there is nothing in the paper to support it, it does not follow. It is interesting to note that some of the authors have already recanted on this particular point, both at WUWT and RC. By the same move, they are also disowning the Carter press release, which is an even bigger non-sequitur. My opinion is that you have demonstrated a depth of knowledge and comprehension of science that are insufficient to afford yourself the kind of sweeping judgements of which you are so generous. In addition, your ideological bias affects your perception beyond what is tolerable for objective critical thinking. The uncritical excitement with which you embraced the McLean/Freitas/Carter paper is a case in point. How closely did you examine that paper? Did you examine it at all? What kind of emotions were going through you when you were reading the authors' statements? Are these emotions conducive to true critical thinking? On top of that, you pasted the Carter press release, without checking if it represented the contents, which it does not. I find it very unsurprising that you would think I am a "socialist", whatever you mean by that word. I am not, and you have nothing to support that assertion since I have kept my ideology to myself so far. There is another non-sequitur: because I disagree with you in the state of the science in general, I must be a socialist. In your world, that is also an ad-hom, since being a socialist is on par with eating raw puppies for breakfast. I have lived on 3 continents and an island. I have lived in places where there are very rich people, and some third world countries as well. I do not subscribe to any ideology pre-formulated in books or other theoretical constructs that attempt to define how people ought to live. All of them fail in the real world, including capitalism. Every socio-economic system based on a theory must make concessions to its basic premises if it is to endure. This is made obvious by the fact that the ones that have endured are full of compromise, even contradictions. It is made even more obvious by the other fact that, when allowed to run wildly toward a theory defined "ideal", all of them eventually fail, no matter what the ideology's name is. I am not young, I have witnessed a number of systems of governance, with various levels of corruption or other non theoretical influences, in a variety of cultures. I find your thinking and your ideology rudimentary, uninteresting and divorced from reality. Perhaps that's why you don't find me so fun. I deeply regret that because, on your end, you have some seriously hilarious moments. I wish I could reciprocate, really.
127674. chris at 00:35 AM on 27 July 2009
        Climate time lag
        Re #238 I don't think any academics (academics?) are "squarking" thingadonta, since your points refer to rather well understood scientific phenomena. Arguments based on ignorance aren't very interesting or useful (see previous discussion on the CRF hypothesis where a fuller understanding of scientific knowledge on this hypothesis highlights the shortcomings of arguments based on the cheeky presumption of ignorance in the reader!). ONE: Ice age cycles. Temperature rises in the Vostock core do precede rises in atmospheric CO2 during glacial to interglacial transitions. However these transitions are extremely slow (the last glacial to Holocene transition lasted around 5000 years, during which global temperatures rose around 0.1 oC per century on average and atmospheric CO2 levels rose 2 ppm per century; they're rising more than 100 times faster now). While temp rises in Vostock cores precede slow CO2 responses, the CO2 responses actually precede temperature rises in Greenland cores, which illustrates the overall (glacially!) slow processes. Overall the atmospheric CO2 rise contributed 1.5 – 2 oC to the ~ 5 oC of the full insolation-drived transition. This is very apparent from modelling of the insolation changes due to Earth orbital cycles (largely the obliquity/precessional components [*]). Since the bulk of the response of raised CO2 levels occurs relatively quickly (say 100 years) on the timescale of the ice age transition, we expect a very, very slow temperature rise contribution from the very, very slow CO2 rise that results from the very, very slow insolation changes. So all of the contributions tend to be rather "mixed together", and we don't expect to see obvious apparent jumps or whatever (not sure what you're expecting to see) from very low-resolution ice cores (a truly vast scientific literature on this – e.g. [**]). [*] http://en.wikipedia.org/wiki/Milankovitch_cycles TWO: Phanerozoic temperature variations: You're ignoring a fundamental element of paleogeophysics, namely the fact that the solar constant has risen progressively from the time of its formation, such that the solar output at the time of the Ordovician was 4-5% lower than the present day solar output. This has some well understood and critical consequences. The most relevant one for this discussion is that the greenhouse gas thresholds for cold/glacial vs warm/hot periods in the past were very different from now. Fundamentally, greenhouse gas levels had to be much higher during the Ordovician than now to maintain cool/warm earth temperature. So it's rather straightforward to calculate that whereas present day strong solar output means that major ice sheets are unlikely to be supportable in the long term with CO2 levels above around 500 ppm, cold periods were inevitable during the Ordovician once atmospheric CO2 levels dropped below around 3000 ppm (there is a large scientific literature on this with CO2-ice thresholds in the range 2240-3920 ppm [***]). There is a certain "Ghia" –ish element to this. Atmospheric greenhouse gas levels generally stay at a value that supports a coolish-warmish Earth, since if temperatures rise high, weathering processes that draw CO2 out of the atmosphere become quite effieicent. On the other hand weathering is suppressed in cooler climbes and atmospheric CO2 levels are maintained. So it's often phenomena external to basic geophysics that greatly perturb greenhouse gas levels and result in major earth temperature variation. These include the evolution of photosynthesising oxygen-producing organisms in the Archaean that resulted in oxidation of methane (the major greenhouse gas during the early ages of the Earth), the unique events around the time of the Carboniferous (major evolutionary phenomena in plants including "invention" of lignin that suppressed oxidative return of plant carbon to the atmosphere and gave us much of the fossil fuel that we are so enjoying burning today), the very well characterised tectonic events that resulted in periodic massive release of greenhouse gases back into the atmosphere with subsequent warming, ocean anoxia and extinctions, and so on. [**] Timmermann A et al (2009) The Roles of CO2 and Orbital Forcing in Driving Southern Hemispheric Temperature Variations during the Last 21 000 Yr, J. Climate 22, 1626-1640. Wolff EW et al (2009) Glacial terminations as southern warmings without northern control, Nature Geoscience 2, 206-209 [***] Herrmann, A.D., Patzkowsky, M.E., Pollard, D., 2003. Obliquity forcing with 8–12 times preindustrial levels of atmospheric pCO2 during the Late Ordovician glaciation. Geology 31, 485–488. Herrmann, A.D., Patzkowsky, M.E., Pollard, D., 2004. The impact of paleogeography, pCO2, poleward ocean heat transport and sea level change on global cooling during the Late Ordovician. Palaeogeogr. Palaeoclimatol. Palaeoecol. 206, 59–74. Royer DL (2006) CO2-forced climate thresholds during the Phanerozoic. Geochimica et Cosmochimica Acta 70, 5665–5675 etc.
127675. Robbo the Yobbo at 21:06 PM on 26 July 2009
        Climate time lag
        Tamino is an authority in time series analysis, whether or not you can recognize it. Tamino - not the hero of the Magic Flute - is an anonomous blogger. Is Grant Foster "Tamino"? I don't know but that's one idea on the net. Do you know or are you just making it up as you go? http://www.aavso.org/news/foster.shtml Since working for the AAVSO, Grant has spent much of his time pursuing his musical career. Playing Irish music festivals and local venues whenever he has the chance, Grant plays guitar and sings Irish ballads. To earn his "real" money, however, Grant works on text categorization for Island Data Corporation based in San Diego where he teaches computers how to classify natural language text.
127676. thingadonta at 20:45 PM on 26 July 2009
        Climate time lag
        Back to climate time lag. I have a question. There is a lag of 400-1000 years between rising T and rising c02 in the Vostok ice core, after previous ice ages (?which possibly follows slowly rising ocean heat releasing c02?). If the earth's climate is so sensitive to c02, why does the curve of T in Vostok ice cores exhibit no change once the c02 actually kicks in- surely, there should be a strong kick in T correlating with the 400-1000 year lag in rising c02, once it kicks in?? Tim Flannery in 'The Weathermakers' states that T rose 5C at the end of the last ice age from a 100ppm rise in c02, (tellingly, he makes no mention of the sun, which actually causes the end of the ice ages, but no matter-it doesnt fit his pre-conceived book title), but if this is true, the 400-1000 year lags in c02 should drive T up 400-1000 years later as well? Also, how come in the geological past, when c02 was eg 10x higher at ~30000ppm or more (eg Ordovician), over several time periods, that earth T was actually cooler in some of these periods than at present? If the IPCC climate sensitivity with regard to c02 forcing is right, this is impossible. At ~3000ppm Co2, T should be about 10C+ higher, if one backdates IPCC models, sensitivities and forecasts. Geological history, methinks, just like it did with creationists, will drive strong c02-forcing theorists extinct and toothless. (I like this topic of climate time lag because it makes some academics squark about like mina birds when my cat wanders past their self-imposed territory. (Mind you, the cat is alien as well.))
127677. Robbo the Yobbo at 17:52 PM on 26 July 2009
        Climate time lag
        I'm sorry - I just had a thought that you are perhaps very young. What is the old expression - a young socialist is an idealist but an old one is an idiot? David asked what someones vision of the world was. Mine is one in which there is not a billion people going hungry. Already we have millions more hungry because food is being turned into fuel. The problem of unanticipated consequences. It makes me very sad and angry. What is the solution? The only one that I can see is continued economic growth. I am not rich. This is not a personal agenda. As I have said, let's make a transition to new energy systems. Inevitable this century anyway. 'Non sequitur (Latin for "it does not follow"), in formal logic, is an argument where its conclusion does not follow from its premises.[1] In a non sequitur, the conclusion can be either true or false, but the argument is a fallacy because the conclusion does not follow from the premise. All formal fallacies are special cases of non sequitur. The term has special applicability in law, having a formal legal definition. Many types of known non sequitur argument forms have been classified into many different types of logical fallacies.'
127678. Robbo the Yobbo at 17:15 PM on 26 July 2009
        Climate time lag
        Furthermore - you the confusing the logical non-sequitor and an ad hominen argument. Ad hominem argument is most commonly used to refer specifically to the ad hominem abusive, or argumentum ad personam, which consists of criticizing or attacking the person who proposed the argument (personal attack) in an attempt to discredit the argument. It is also used when an opponent is unable to find fault with an argument, yet for various reasons, the opponent disagrees with it. Many of your statements would fit this description.
127679. Robbo the Yobbo at 17:08 PM on 26 July 2009
        Climate time lag
        What do you think the Swanson paper means? Nothing makes any sense because the discussion keeps going of into wild tangents to avoid the reality of episodic climate shifts in particular. And I really just started with a comment on changing Earth albedo. But no matter how reasonable I try to be - the same things keep coming back in new twists. I did not accuse David of bias but of not being authentic in the Laingian sense. The same may apply to you.
127680. Robbo the Yobbo at 17:01 PM on 26 July 2009
        Climate time lag
        These guys are a lot more fun than you. http://wattsupwiththat.com/2009/06/13/results-lab-experiment-regarding-co2-snow-in-antarctica-at-113%C2%B0f-80-5%C2%B0c-not-possible/ But I think this is probably the definitive site on global whining. http://kidsagainstagw.com/2009/02/04/global-whining/ "Human beings seem to have an almost unlimited capacity to deceive themselves, and to deceive themselves into taking their own lies for truth … the result … is that (we have) been tricked and (have) tricked ourselves out of our minds, that is to say, out of our own personal world of experience …" (J.D. Laing).
127681. Philippe Chantreau at 16:17 PM on 26 July 2009
        Climate time lag
        You need to review your logic Yobbo. Theoretical (purely) example of ad hominem attack: Robbo the Yobbo eats little puppies for breakfast (without cooking them), therefore he has no clue on atmospheric science. That would be a real ad hom and a logical fallacy, regardless of the veracity of the puppy premise. Now, the following is quite different: Robbo the Yobbo says that atmospheric CO2 could possibly sublimate out of the atmosphere and fall as snow. When pointed to the ludicrousness of the idea he says that he meant very very small amounts in some place very very cold. Therefore Robbo's opinion on atmospheric science is of very limited interest. That is not an ad hom, neither it is a logical fallacy. Tamino is an authority in time series analysis, whether or not you can recognize it. Neither of the authors of the paper discussed has a significant record of publication in statistical methods or time series analysis. Saying that Tamino has more expertise than any of them on that subject does not constitute an ad hom nor an appeal to authority. Roy Spencer has made ridiculous arguments that contradict everything known about the carbon cycle. He and Christy have let people use faulty UAH data for political purposes while they knew the data were faulty. Eventually their mess had to be corrected by someone else. Yet you are yourself using Spencer in an appeal to authority, going as far as listing his credentials. Accusing others of one own's faults is a common strategy among the intellectually dishonest. At least you acknowledge your ideological drive. Which brings us to this question: why would your ideology make you better able to objectively look at the science and form a better understanding of it than anyone else's? Why should you not be as biased as those you accuse?
127682. Robbo the Yobbo at 14:50 PM on 26 July 2009
        Climate time lag
        They are talking about past climate cycles. 20 to 30 year cycles of warming and cooling. Between these 'climate shifts' the most recent warming rate due to all other causes was 0.1 degree C/decade. On this basis they hypothesise that the current warming hiatus may persist until perhaps 2020. You may doubt any of this but should at least not misrepresent the paper.
127683. David Horton at 14:14 PM on 26 July 2009
        Climate time lag
        I know this is futile, but you haven't understood anything about the RC paper you so happily quote (and I bet that's a first, why don't you quote from any of the other material there?). Again, you did read "it’s important to note that we are not talking about global cooling, just a pause in warming" didn't you? In summary the HYPOTHESIS the paper puts forward is that 1998, instead of just being a particular high outlier in the random variation around the ever-increasing mean temperature, represents a sudden upward jump. Why you would think that a sudden upward jump (if they are right) is better for your attempts to prevent any action to stop the planet cooking is better than a steady increase is beyond me, clearly.
127684. Robbo the Yobbo at 13:26 PM on 26 July 2009
        Climate time lag
        And it was actually realclimate that stimulated the uncertainty note. It is probably less embarassing than a backflip with triple pike. 'Nature (with hopefully some constructive input from humans) will decide the global warming question based upon climate sensitivity, net radiative forcing, and oceanic storage of heat, not on the type of multi-decadal time scale variability we are discussing here. However, this apparent impulsive behavior explicitly highlights the fact that humanity is poking a complex, nonlinear system with GHG forcing – and that there are no guarantees to how the climate may respond.’
127685. Robbo the Yobbo at 12:24 PM on 26 July 2009
        Climate time lag
        I didn't say it was a good reason to act but it is better than what you have now. 'Imagine, twenty-two or more years (1998 to ~2020) of no new global temperature record. What would that do to the debate?' Well, it has been charmless but pointless.
127686. David Horton at 11:10 AM on 26 July 2009
        Climate time lag
        "uncertainty is a far batter reason for justifying action ". I think there is a typo there and you meant to say "uncertainty is a far battier reason for justifying action". I never cease to be amazed by this stuff. Black is white, up is down, today is yesterday. Mr Yob is arguing here, in case you were uncertain about what on earth he was saying, that politicians are not going to act because the climate is certainly changing as a result of CO2, rapidly and for the worse. Oh my goodness no. They will only act because the babble of denialists, deliberately pretending that there is debate and alternative answers where none exist, have created uncertainty about the future. So amid all this uncertainty, politicians will swing into action, convincing the public, also battered by the endless stream of nonsense from denialists, that firm action is needed on greenhouse gas emissions. Yeah, that works for me. I think I'll start pretending to believe in cosmic rays and clouds and CO2 release from oceans, and sun spots, and wobbling planets, and global warming on Mars, and argue so convincingly that politicians will swing into action. How could I have thought that presenting reality would do that?
127687. Robbo the Yobbo at 10:04 AM on 26 July 2009
        Climate time lag
        Ah Phillipe - an ad hominen attack and an appeal to dubious authority. I expect nothing less. I refer to dozens of websites. Inevitably these are links to published papers (for the convenience of others) and good sources of up to date data. The latter is something the internet was made for. These is never any reliance on dubious sources. I have copied over my references to the people named below. And here is a quote from Pielke Jn from the page linked to. Read the full entry below. ‘As I've argued many times, uncertainty is a far batter reason for justifying action than overhyped claims to certainty, or worse, claims that any possible behavior of the climate system is somehow "consistent with" expectations. Policy makers and the public can handle uncertainty, it’s the nonsense they have trouble with.’ It is not something that I rely on – but something that I agree with. Particularly the nonsense bit. Yours with absolutely no respect Robbo The Spencer and Braswell link was a reference to a Journal of Climate paper. “See Spencer and Braswell - http://www.drroyspencer.com/Spencer-and-Braswell-08.pdf for the implications for TOA radiative balance for varying cloud cover. Changing cloud cover falsifies the Hanson paper referred to above. “ This is the link to Shaviv. “I have provided references. There is a link to a 42 page summary from CERN’s Jasper Kirkby. It appeared in Surveys in Geophysics 28, 335-375 (Nov 2007) – but is available on the CERN server. There are several references linked to on ScienceBits: http://www.sciencebits.com/CosmicRaysClimate Check out Figure 3 on the site – but of course never relying on a single source.” Dr Roy Spencer again http://www.drroyspencer.com/latest-global-temperatures/ - UAH temperature – it also appears on a NASA site. Roger Pielke? “http://www.uwm.edu/~kswanson/publications/2008GL037022_all.pdf http://www.realclimate.org/index.php/archives/2009/07/warminginterrupted-much-ado-about-natural-variability/ Read carefully because Swanson supplies all necessary pre-digested rationalisations for global warmists. Although it is not new or startling science it is capitulation to the bleeding obvious. http://rogerpielkejr.blogspot.com/2009/07/two-decades-of-no-warming-consistent.html Roger Pielke Jn – definitely in connection to the Swanson paper. 13 July 2009 Two Decades of No Warming, Consistent With . . . Over at Real Climate they are busy giving climate skeptics reason to cheer: ‘We hypothesize that the established pre-1998 trend is the true forced warming signal, and that the climate system effectively overshot this signal in response to the 1997/98 El Niño. This overshoot is in the process of radiatively dissipating, and the climate will return to its earlier defined, greenhouse gas-forced warming signal. If this hypothesis is correct, the era of consistent record-breaking global mean temperatures will not resume until roughly 2020.' Imagine, twenty-two or more years (1998 to ~2020) of no new global temperature record. What would that do to the debate? Real Climate does say something very smart in the piece (emphasis added): Nature (with hopefully some constructive input from humans) will decide the global warming question based upon climate sensitivity, net radiative forcing, and oceanic storage of heat, not on the type of multi-decadal time scale variability we are discussing here. However, this apparent impulsive behavior explicitly highlights the fact that humanity is poking a complex, nonlinear system with GHG forcing – and that there are no guarantees to how the climate may respond.’ As I've argued many times, uncertainty is a far batter reason for justifying action than overhyped claims to certainty, or worse, claims that any possible behavior of the climate system is somehow "consistent with" expectations. Policy makers and the public can handle uncertainty, it’s the nonsense they have trouble with.
127688. Philippe Chantreau at 02:40 AM on 26 July 2009
        Climate time lag
        Yobbo has a memory as selective as his readings. His very first post on this thread has a link to Spencer's blog, then he linked to a variety of them: Shaviv's blog, PielkeJr., Spencer again. In fact, he might possibly be the one with the most blog references in the all thread. Don't recall eh? I'd say. Tamino has published numerous papers on statistical methods and time series analysis. He knows more about the subject than any of the authors of the paper linked by Yobbo. And yes, Donta, by all means keep coming up with stuff like the diurnal temperature "heat lag". It's almost as fun as Yobbo's carbonic snow falling in "minute amounts" in a very very cold place. Keep up the good work, indeed.
127689. Robbo the Yobbo at 20:39 PM on 25 July 2009
        Climate time lag
        Well David - it's this way - the only blog I think I referred to (and no I can't be bothered checking) was realclimate - and that was just being provocative. I’ll make sure I get another good spanking. Really they are as appalling as anyone else. (Save Gaia says - ...Montreal Protocol?) I think it must be the human condition. I don't recall referring to Pielke Jn before - although it might have been in relation to the Swanson paper. Certainly the junk is far from one sided. I can give a good example at Niche Modelling and Jennifer Maroshy with that appallingly silly Miscolcsi theory. Oh my god - you mean somebodies got something wrong on the internet? Tamino is irrelevant. And he doesn’t understand the decadal variations I have been rabbiting on endlessly about. So he doesn’t understand what McLean et al are saying and it is simply a kneejerk reaction full of sound and fury but signifying nothing. To quantify the trend from decadal climate shifts is not something that people have been able to work out – but to claim that because the method can say nothing directly about trend the variance result can be neglected. That is the confidence trick. But let’s wait until Tamino publishes. The 80% explanation of variance in the tropics 7 months after the SOI is a good little result. 80% is astonishingly high if confirmed. I don’t know you’re doing – but I’m going back to see what the SOI was in December last year. Although as Mike Hulme says, to “hide behind the dubious precision of scientific numbers, and not actually expose one’s own ideologies or beliefs or values and judgements is undermining both politics and science". Keep up the good work Mr. Donta. There is a political battle to be won. I think this discussion must be finished Cheers Robbo
127690. Philippe Chantreau at 17:58 PM on 25 July 2009
        Climate time lag
        Yobbo's funny is of the best kind, David: inadvertent. Yobbo: "We have peer reviewed science on the one hand and the simple minded blogosphere on the other." That's precious. By all means let's apply that to CA, the carbonic snow dudes at WUWT and all the other junk out there. If blogs are so bad why did you refer to blogs earlier on this thread, including that of Pelke jr who is a political scientist, hence a lot less qualified on any real scientific subject than Tamino is on statistical analysis? Your total incomprehension of what Tamino does suggest that the simple minded part of the blogosphere might not be the one you suggest. The "trick" shows that, even with a massive trend over SOI induced variations, Carter's results would be exactly the same. With a cooling trend or no trend, no difference. Which part of that do you not understand? Or do you just fail to see the implication?
127691. David Horton at 17:53 PM on 25 July 2009
        Climate time lag
        Ah Yobbo, great to see that you are a denialist with a sense of humour! Sadly very rare. Don't ever change.
127692. Robbo the Yobbo at 13:49 PM on 25 July 2009
        Climate time lag
        Bjorn Lomberg is an economist who repeatedly says that he doesn't question the climate science. Roger Pielke Jr is a political scientist who again doesn't question the science. Profesor Mike Hulme is currently a visiting fellow at the Tyndal Centre - specialises in climate research and advises the IPCC. Your point is ????????????????????????????????????
127693. David Horton at 13:30 PM on 25 July 2009
        Climate time lag
        "Bjorn Lomberg, Roger Pielke Jr and eminent climate scientist Mike Hulme, none of whom are notable skeptics". ???????
127694. Robbo the Yobbo at 13:07 PM on 25 July 2009
        Climate time lag
        The peer reviewed paper uses standard correlation techniques for estimating co-variance. There is nothing intrinsically wrong with statistical correlation. I refuse to comment further on Tamino's cynical manipulation of the woefully gullible. It is a blog - and it would seem not to be in keeping with the aims of this site to uncritically prefer convenient blogs over peer reviewed science because it suits your pre-conceived notions. And I suggest that NYJ considers the implications of decadal climate states before weighing in with simplistic analysis. Again, I wonder, with Swanson, what could fundamentally challenge 'the global warmist' understanding of climate science. Certainly not science. Any science that doesn't agree is dismissed without reading as dodgy, embarassing, and numbers of other pjorative terms. Eminent scientists and other persons are insulted by pimply adolescents in the name of a cause. Even people such as Bjorn Lomberg, Roger Pielke Jr and eminent climate scientist Mike Hulme, none of whom are notable skeptics - are demonised for not following the policy line. "To hide behind the dubious precision of scientific numbers, and not actually expose one’s own ideologies or beliefs or values and judgements is undermining both politics and science", says Mike Hulme. I am not denying basic atmospheric physics. I simply believe with Swanson that: ‘the nature of these past shifts in climate state suggests the possibility of near constant temperature lasting a decade or more into the future must at least be entertained. The apparent lack of a proximate cause behind the halt in warming post 2001/2002 challenges our understanding of the climate system, specifically the physical reasoning and causal links between longer time-scale modes of internal climate variability and the impact of such modes upon global temperature.’ After 20 years of reading on decadal rainfall, oceanographic and lately, global atmospheric changes, I would put it much more strongly. The Pacific dominates these climate states - and global temperatures. We have only a couple of cycles on the climate record – not nearly enough information to be definitive about this phenomenon. Swanson and Tsonis, McLean et al and many others in hydrology and physical oceanography reveal tendencies. But the real proof is in the pudding. Continued atmospheric temperature decline, a huge fisheries boost particularly in the eastern Pacific, a decline in ocean heat content, increasingly frequent and intense La Niña (and at the same time – less frequent and intense El Niño), much more rainfall in Australia. In the current cool mode of the Pacific Decadal Oscillation – the current pre El Niño state will not evolve into more than neutral or weak El Niño condition in the Southern Hemisphere spring. Record temperatures will not return any time soon.
127695. NewYorkJ at 11:50 AM on 25 July 2009
        Climate time lag
        Expansion on #217: la Nina years since the mid-70's: 1974: -0.10 1975: -0.03 1976: -0.11 1985: 0.06 1989: 0.21 1996: 0.26 1999: 0.40 2000: 0.37 2008: 0.49 Mostly isolating the ENSO influence by looking at just la Nina years, we still seen a strong positive linear trend during this period. ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/annual.land_and_ocean.90S.90N.df_1901-2000mean.dat
127696. thingadonta at 11:06 AM on 25 July 2009
        Climate time lag
        re:216 "That kind of blind faith must be a great comfort." It is NOT blind faith to conclude that climate change is being driven largely by the sun. I'll keep saying this as long as you keep making false accusations. Why don't you get a job as a prosecutor for some totalitarian communist country? Your tendancy to make false accusations to support an ingrained bureaucratic ideology would go down well. "And do you really believe that the best that human beings are capable of, in society, culture, economy and environment, is to be managed by the leaders of giant corporations? Is that your vision for humanity?" If you had read or understood anything I said, you would see that I didn't say that. I am going to go out on a limb here, but since you always stoop first to make personal remarks and false accusations I reckon this is ok this time, but let me take a guess what your line of work is. My first choice would be public service for a long period, since you can't tell what is going on in the real world anymore, can't analyse data, and have married yourself to self-serving academic-public service ideology, with a stream of false accusations against anyone who holds different views. You can't be a journalist, because journalists actually investigate, you just parrot out ideas that serve the interests of an administrative class. You can't be a politician, because politicians wouldn't lower themselves to public debate. You could be a scientist or academic, but since you can't examine data in any meaningful way, it is probably in a field where that isn't really required, such as in the arts. (But then again, I know that some academics are so bad at analysing data that is doesn't make much difference). My guess is a background in humanities, a long public service career, with some scientific training somewhere, in a field where data analysis is weak. (If this is inappropriate ad hominim stuff, you shouldn't resort to it either). Getting back to the topic of climate time lag...since the oceans have been warming for soem time, including eg 1955-1998, c02 released from a warmer ocean should continue to rise for several hundred years (there is always a long lag between rising T and rising c02 from oceans), irrespective of human c02 activities. But since this lag rise in c02 hasn't affected T in previous interglacials, (T rise in interglacials is driven by the sun, followed by c02 hundreds of years later which doesnt do anything)) it shouldnt affect T much in the next few hundred years either.
127697. David Horton at 10:52 AM on 25 July 2009
        Climate time lag
        "The trend is a trick"? perhaps you could define "variance" and "trend" for us in denialworld Yob. Why on earth do you think that people didn't know that El Nino La Nina changes explain much of the variance? What does this have to do with the overall clear trend in rising temperatures?
127698. Robbo the Yobbo at 10:31 AM on 25 July 2009
        Climate time lag
        No - just that there is no useful purpose to be served by adding 'a very strong (linear) trend' and then reexamining the covariance. I repeat what the paper shows is that 80% of temperature variance is explained by the SOI. The trend is a trick. We have peer reviewed science on the one hand and the simple minded blogosphere on the other. Is the alternative that we get managed by the equivalent of the Chinese Communist Party instead? Or is this a vageur and more utopian fantasy? The latter would match your mathematics.
127699. NewYorkJ at 10:27 AM on 25 July 2009
        Climate time lag
        Regarding the odd "ENSO explains most everything" claims, aside from relying on hazardous UAH data, or the embarrassing methodology in the recent paper (exposed by Tamino), one can also observe the trends during specific la Nina years (year after episode begins). Examine temperature anomalies from 1974,1975,1976, 1985, 1989, 1996, 1999, 2000, 2008. Note from these data points we get about 0.5-0.6 C of warming over this period during exclusive la Nina years. Repeat the analysis for el Nino years and we see a similar strong warming trend. Of course, one needs to account for their strength as well. 1998 was obviously a whopper el Nino year. ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/annual.land_and_ocean.90S.90N.df_1901-2000mean.dat http://www.cpc.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf
127700. David Horton at 09:23 AM on 25 July 2009
        Climate time lag
        "Tamino adds a fake linear trend – which cannot by itself change the covariance – and which then becomes the argument." This is the kind of misunderstanding, or willful misleading, which has been seen throughout this thread. Tamino in fact adds a very strong trend, to show that no matter how strong a trend is present, the analysis in this paper removes it. That is, whatever the trend, it disappears, mathematically. To then turn around and say that this demonstrates there is no trend shows a misunderstanding, or willful misleading, by the authors concerned, who would feel right at home here. #212 Thingy I'm happy for you in your ideology. That kind of blind faith must be a great comfort. But do you really think that faced with climate change, caused, in effect by the unfettered operation of markets, you can solve the resulting problems by market forces? And do you really believe that the best that human beings are capable of, in society, culture, economy and environment, is to be managed by the leaders of giant corporations? Is that your vision for humanity?

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