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Comments 129651 to 129700:

129651. chris at 07:28 AM on 19 May 2009
        Does ocean cooling disprove global warming?
        re #12 Ron, you're not really addressing the subject, but just dumping stuff (what's the relevance of tree rings to ocean heat content?). Let's take Pielke's assertion at face value: "Thus, according to the GISS model predictions, there should be approximately 5.88 * 10**22 Joules more heat in the upper 700 meters of the global ocean at the end of 2008 than were present at the beginning of 2003." O.K. fine. According to Levitus the end 2002 accumulated heat content was around 8.7 x 10^22 J and by the end 2008 it was around 14.5 x 10^22 J. That's around 5.8 x 10^22 J more heat in the upper 700 meters of the global ocean at the end of 2008 than were present at the beginning of 2003. So what's the problem? The accumulated heat seems to be right on the button in relation to Pielke's assertion of what the accumulated heat should be if the GISS model projection is required to be absolutely correct Of course like many measurements in the real world the data are somewhat noisy, and we are all aware of the problems (and the temptation!) of making interpretations based on observations over short periods of time. However one can hardly assert that there are problems with measurements compared to predictions when the measurements are almost exactly the same as the prediction.
129652. Ron Cram at 06:01 AM on 19 May 2009
        Does ocean cooling disprove global warming?
        Roger Pielke, the ISI highly cited climatologist referred to above, has blogged on a recent paper by Levitus regarding recent Argo instrumentation problems. He references a number of key papers. The biggest problem with the Levitus paper is that it does not even address the recent lack of warming. http://climatesci.org/2009/05/18/comments-on-a-new-paper... Pielke writes: "Thus, according to the GISS model predictions, there should be approximately 5.88 * 10**22 Joules more heat in the upper 700 meters of the global ocean at the end of 2008 than were present at the beginning of 2003. "For the observations to come into agreement with the GISS model prediction by the end of 2012, for example, there would have to be an accumulation 9.8 * 10** 22 Joules of heat over just the next four years. This requires a heating rate over the next 4 years into the upper 700 meters of the ocean of 2.45 * 10**22 Joules per year, which corresponds to a radiative imbalance of ~1.50 Watts per square meter. "This rate of heating would have to be about 2 1/2 times higher than the 0.60 Watts per meter squared that Jim Hansen reported for the period 1993 to 2003. "While the time period for this discrepancy with the GISS model is relatively short, the question should be asked as to the number of years required to reject this model as having global warming predictive skill, if this large difference between the observations and the GISS model persists.” Also, I contacted Craig Loehle to tell him his paper on ocean cooling was being discussed here. Perhaps he will comment. Also, his paper explaining why tree rings are not valid thermometers has been published. http://www.springerlink.com/content/45u6287u37x5566n/ Loehle and McCulloch also published a corrected 2,000 year temperature reconstruction correlated to temperature without using any tree rings. Interestingly, it did not confirm Michael Mann's Hockey Stick. http://scienceandpublicpolicy.org/images/stories...
129653. Dan Pangburn at 05:46 AM on 19 May 2009
        It's the sun
        Patrick 027 I have been searching for a metaphor to possibly provide insight into the relation between Climate Science and Control Theory. This is a poor one but will have to do until a better one comes along. Climate Science is like the complete definition of how to engineer a car. It defines everything in detail. For the car it would include the required size of gears, diameter of drive shafts, steering gear ratio, seat height, tire size, wire size, etc. etc. Control theory is like the patrolman who observes that the car is being driven too fast. The patrolman doesn’t need to know anything about how to design a car. He doesn’t need to know if some of the calculations may have contained errors. He doesn’t even need to know if there are factors making the car go that no one understands or even knows exist. In 386 you presented a huge list of details of what contributes to weather and by extension climate. I am not qualified to challenge that list, or determine if it is correct, adequately complete or even address it. In Control Theory, ALL of that gets lumped together into a box called ‘control/plant’ which is defined as ‘all factors that influence average global temperature’. The factors do not need to be defined in detail. They do not need to be correct. They do not even need to be known. By definition the ‘box’ in the Control Theory model contains ‘all factors that influence average global temperature’. The output in this Control Theory model is (by definition) average global temperature. Feedback is (by definition) the effect that average global temperature has on ‘all factors that influence average global temperature’. It is a trivially simple model but the science behind it is extremely powerful and proven in nearly endless successful applications. The planet itself is a perfect computer for weather and climate that, by definition, correctly accounts for all factors. The output from that computer is archived in ice cores and sediments. Using proxies, scientists have teased temperature anomalies (changes from a reference value) that are validated by being done by different people using different methods. For this assessment using Control Theory the data does not even need to be accurate in an absolute sense only reasonably representative in relative amplitude. Many sources report this data and a few are plotted from identified credible sources in my pdf file linked from http://climaterealists.com/index.php?tid=145&linkbox=true . The thing to be observed about this data is not the short term oscillations that average out but the long term trends of hundreds or even thousands of years. Now comes the crucial observation that may take an understanding of Control Theory. Repeatedly during the last and previous glacial periods, a temperature increasing trend changed to a decreasing trend and vice versa. With knowledge of Control Theory it is recognized that this is not possible if there is net positive feedback from temperature unless it is triggered by an external stimulus that is more powerful than the feedback. The observed temperature trend changes show that any positive feedback effect must have been smaller than the external stimulus. That is, the external stimulus called the shots and net positive feedback, if any, was less significant. The higher level of atmospheric carbon dioxide now results in changes to atmospheric carbon dioxide level being even less significant. If an AOGCM predicts otherwise it is either faulty or misused or both. It is unfortunate that most if not all Climate Scientists are unaware of Control Theory (it’s not in their curriculum). If they were knowledgeable in Control Theory they might not have made the egregious mistake of blaming Global Warming on added atmospheric carbon dioxide and misleading a whole lot of people. As far as one degree being significant, realize that it is one degree from the pre-industrial period and most of that has already occurred. I personally think that the influence of atmospheric carbon dioxide is much less than one degree and the temperature run-up at the end of the 20th century was a result of the Solar Grand Maximum combining with a PDO uptrend, both of which are now going the other way. If the politicians will just stay out of it, the free market will bring about acceptable solutions to the issues of finite supplies of fossil fuels.
129654. Patrick 027 at 04:54 AM on 19 May 2009
        It's the sun
        If Control Theory makes any sense at all, I don't get that from your posts (no offense), so I'm going to look it up elsewhere. (If there were no positive feedback, the temperature would not go up and down as much as it does.) "This is kind of vague but appears to expose a fundamental lack of understanding of how gases absorb photons. Perhaps it would help to study work by Dr. Jack Barrett" I skimmed it. From that: " The GCMs take feedbacks into account, such as the supposed positive feedback from extra warming caused by the absorption of radiation by extra water vapour. Such feedbacks have to be parameterised and although they may contribute a greater reality to the models, they also introduce extra uncertainties." No, the feedbacks are not parameterized; they are part of the climate model output. Parameterization is required for sub-grid scale processes... http://www.realclimate.org/index.php/archives/2007/01/the-physics-of-climate-modelling/langswitch_lang/sw --- But anyway, I have a really good understanding of radiative energy transfer in the atmosphere as it relates to bulk properties (emissivity and absorptivity, scattering cross section, etc, as a function of wavelength) - I have less detailed knowledge of the microscopic and quantum-mechanical mechanisms that give rise to this behavior, though I do understand the generalities (collision/pressure broadenning and doppler broadenning of line spectra, for example). My point was that, within some range of conditions, the tropopause level the radiative forcing by CO2 (integrated over all wavelengths and directions) can be approximated with a logarithmic relationship. This alone says little if anything of the relationship of the temperature response to radiative forcing. (PS - important (note this, Gord) - at sufficiently low CO2 levels, the relationship becomes more linear. Removal of all CO2 would not be an infinite negative radiative forcing - as I recall, I think it would be somewhere between -20 and -30 W/m2. With nearly 4 W/m2 forcing per doubling, this suggests that the logarithmic proportion must become inaccurate before 5 or 6 halvings.)
129655. chris at 02:20 AM on 19 May 2009
        Does ocean cooling disprove global warming?
        In an ideal world subject to ideal monitoring, the oceans shouldn’t lose heat while the climate system is in positive radiative imbalance. That seems to be the ideal to which DiPiccuo and Pielke are staking their claims on. That differs somewhat from the surface temperature record where year on year variation can incorporate true temperature decreases since year on year variation in the climate system can “overpower” the very marginal yearly temperature increase due to greenhouse forcing, and the surface temperature isn’t a measure of total heat content in the Earth system. So 2008 with a strong La Nina, and a solar minimum gives a real (and not unexpected) reduced surface temperature compared to the preceding years. However the expectation is that the radiative balance in 2008 is still in positive dis-equilibrium even if the excess radiative forcing is reduced somewhat. So the oceans should continue to absorb heat in 2008, but less strongly. Does that make sense? That’s how I see it… The question then is whether we occupy an ideal world, ideally monitored. In my opinion the latter is the origin of the uncertainties upon which DiPiccuo and Pielke play fast and loose! 1. There does seem to be uncertainties in the monitoring systems. I read the Levitus paper [*] (see fig 2 in John Cooks great summary above) last night, and this analysis, ‘though not the last world probably, does support the conclusion that ocean heat has continued to accumulate during the period from 2003, consistent with the analyses of steric (warming) and mass (glacial melt) contributions to sea level rise in recent papers. 2. The variation in the Levitus data (e.g. the very large jumps in ocean heat content from 2002-2004) is odd and may or may not be real. However if one considers the long term trend, that’s more likely a reasonable measure of the ocean heat uptake. Levitus annotate their Fig 1 (equivalent to John’s figure 2 above) with a trend (1970-2008) of 0.4 x 10^22 J per year. I worked out the trend from 1985-2008 is 0.6 x 10^22 J per year. 3. If the jumps in the data are real, then the most likely explanation might be the redistribution of ocean heat in the way that Dave Horton indicates (e.g. El Nino years excess warmth in the surface waters of large regions of the Pacific; La Nina years more surface heat taken down to the deeper oceans at the expense of more upwelling cold waters). The question then becomes whether these ocean currents take pools of cold or warm water outside the monitoring system, or the measuring of these pools becomes somehow biased as they redistribute in the oceans… 4. So there is some uncertainty over these issues. That’s obviously why we shouldn’t attempt fundamental conclusions on the basis of a few years worth of data! 5. Incidentally, it’s interesting to consider Pielke’s analysis of these issues, which I looked at in response to Ron Cram’s assertions on the preceding thread (see the link to Pielke’s web blog in his first post there). Pielke considers that the ocean cooling (which we now know very likely isn’t cooling at all!) casts grave doubts on our understanding of the greenhouse effect and the consequences of enhancing atmospheric greenhouse gas levels. He asserts that for “a requirement to NOT reject the IPCC claim for global warming“, various criteria of heat content should be satisfied. Thus, for example, the added upper ocean heat content must be (according to Pielke) at least 13 x 10^22 J by the end of 2008, and he asserts elsewhere that the upper oceans should have acumulated 5.88 x 10^22 J in the period end 2002 to end 2008 (if Hansens radiative imbalance GISS model projections are to be satisfied). He then proceeds to ridicule the modelling with a list of years 2003, 2004, 2005, 2006, 2007, 2008 each with “~ 0“ as their accumulated heat content! However if we compare Pielke’s proscriptions with the Levitus data, we find that the accumulated heat in the upper oceans is around 14.5 x 10^22 J at end 2008, and the accumulated heat in the upper oceans between end 2002 and end 2008 is close to 5.8 x 10^22 J. O.K. so we can quibble with this sort of “numerology“, and we accept that these data cannot be treated as being rock certain measures of reality. However the data actually conform to Pielke’s proscriptions, even though he was raising them in an attempt to trash the modelling.....which is interesting....
129656. Ian Forrester at 01:08 AM on 19 May 2009
        Does ocean cooling disprove global warming?
        John the information on the depth of ARGO bouys was obtained from this document: ftp://ftp.gfdl.gov/pub/ysc/Global_OA/REV1/replies.pdf I haven't a clue who any of the participants in the discussion are.
129657. John Cross at 23:38 PM on 18 May 2009
        Does ocean cooling disprove global warming?
        A couple of comment about ARGOS vs. XBT. An ARGOS buoy is a full CTD capable instrument as opposed to an XBT which is just temperature. This means that the CTD is recording temperature at a depth calculated from pressure. The XBT is transmitting temperature at a depth that is essentially preset, in other words the depth is found from the rate of sinking of the XBT which has been previously calculated. So it is using an estimated depth. While I have some experience with CTDs I have little with XBTs. however, my gut feeling is that the instrumentation in the CTD is of better quality than the BXTs. Ian, great link to the physics form. Interesting read. One comment, I think that most ARGOs go deeper than 700 meters. I thought that prior to sending out the data most would sink to about 2km than do a full CTD cast all the way up. Regards, John
129658. David Horton at 18:52 PM on 18 May 2009
        Does ocean cooling disprove global warming?
        #1 Philippe - I guess the logic would be that the ocean mass is so great that changes in temperature will be very slow, damping out the kind of fluctuations you can get in air. But as Ian points out, this ignores salinity change and mixing of levels. It also ignores changes in the movement of water masses. I may well be misunderstanding something about the logic, but don't such phenomena as La Nina/El Nino argue for at times quite rapid changes in ocean temperature regionally? And wouldn't this be potentially reflected in the movement of other streams in the ocean? But above all, the 5 year sequence shows the same cherry picking that has become so familiar over the last couple of years. I guess the only difference here is that they are arguing that this is a general reflection of global changes because of the energy inertia of the ocean system.
129659. gv at 18:29 PM on 18 May 2009
        Does ocean cooling disprove global warming?
        Does argo probe deeper as well??
129660. thingadonta at 16:17 PM on 18 May 2009
        It's not bad
        Some of your pros and cons listed above and not correct. The longer geological record contradicts statements made by the IPCC and other climatologists, because the IPCC and other climatologists don't usually bother to consult the longer geological record, and the usual argument from climatologists is that 'geologists are not climate scientists', which is false; climate is a subset of geology (earth science), not the other way around, (with both ultimately a subset of astronomy). The longer geological record has much to say about the lists you have given above, for eg: -Increased desertification corresponds to globally cool periods, NOT warm periods, in the geological past, (which is the opposite of what the IPPC projects). This genrally means that African and the US, and some Asian crop yields will increase with warming, not decrease. Globally, there is more rainfall. Africa, for example, began to become drier with the onset of glacial periods several million years ago, with larger areas of savannah and reduced rainforest cover, (which may well have led to the evolution of the savannah-ape line-that's us). -Warm periods do not correspond with increased extinction in the geological record, rather, biodiversity increases (which is the opposite of what the IPCC projects) -Coral reefs thrive during sea level rise, whilst sea level falls produce extinction. -Coral reefs thrive during warmer periods, and oceans do not become acidic from greatly increased C02; there were many periods of thriving corals and other marine life in the geological record when C02 was much higher than today. -Polar bear populations have survived the many warm interglacials in the last several hundred thousand years, warmer periods do NOT promote their extinction. The bigger threats to polar bears are ecotourists, bureaucrats, and hunters. -The Tibetan plateau began to rise around 30-40 million years ago; changes in short -term climate are paradoxical and not thought to greatly affect water supply/runoff in this region as much as longer period changes in elevation; as during globally warmer periods snow (and rain) precipitation increases along with seasonal meltwaters-particularly on the Chinese (cooler) side, whilst in cooler periods ice and snow cover increases but overall precipitation and seasonal meltwater generally decreases. Other points: -Crop yields at all latitudes increase with increased C02, (already an estimated 15% since about 1850), the same goes for tropical rainforests,(the Carboniferous period had high vegetation levels and high C02-much higher than at present) -Both Europe and USA have thrived in warmer periods, both ecologically (in the past) and economically during human occupation eg reduced energy consumption for heating, increased rainfall, less droughts, less deserts (USA). -Lakes do no "vanish" on a global scale during globally warmer periods; if anything it is generally the opposite (point 1 above-lower desertification occurs during warmer periods). I could dig up alot of other longer geological record indices, but again, what surprises me is the complete ignorance amongst many who promote various global warming scenarios/projections on what the actual record of the earth itself has to say on these matters. A similar thing occurs with creation scientists, and in various discussions and debates within biology about evolution; the longer geological record is usually ignored (other than the usual-'the fossil record is incomplete'), when it was the geological record that formed the general foundation about thinking about evolution in the first place, and has alot to say about it. Another related topic is the long history of debates around catastrophism and uniformitariaism-which also have much to say about current issues/debate concerning global warming-but that is for another day and another thread. In general, there needs to be more input/integration from the actual geological record on various climate change scenarios/issues, which directly contradict some of the (surmised/projected) points in your list above.
129661. Dan Pangburn at 15:47 PM on 18 May 2009
        It's the sun
        Patrick 027: Wow! You have been busy . . . This responds to 383. I will read your latest tomorrow. The egregious mistake that the Climate Science Community is making is obvious to those who understand Control Theory that have looked at the paleo temperature data. From your comments it is also obvious that you are unfamiliar with Control Theory. With knowledge of Control Theory you would recognize that your statements in 383 are mostly nonsense. With Control Theory it is trivial to determine that there is no net positive feedback from average global temperature. With no net positive feedback added atmospheric carbon dioxide has no significant effect on average global temperature. “This ignores the possibility that the temperature variations were externally forced. Positive feedback causes a cyclic variation in response to a cyclic forcing to be larger in amplitude than otherwise.” Quite the contrary, it proves that temperature changes from up-trend to down-trend (or vice versa), were externally forced. Selection of a suitably long trend avoids cyclic issues. “It also ignores that feedback mechanisms work differently on different time scales” This and later comments demonstrate a lack of understanding of what feedback means in a dynamic system like earth’s climate. “The logarithmic proportionality of radiative forcing to CO2 level has no direct bearing on the climate sensitivity to radiative forcing.” This is kind of vague but appears to expose a fundamental lack of understanding of how gases absorb photons. Perhaps it would help to study work by Dr. Jack Barrett at http://www.warwickhughes.com/papers/barrett_ee05.pdf “Actually, cloud feedback in climate models is small and ranges from negative to positive; the dominant positive feedbacks are water vapor and albedo.” A recent paper by Dr. Spencer addresses cloud feedback and points out the previous over-estimation of climate sensitivity by the IPCC. It can be seen at http://www.drroyspencer.com/research-articles/satellite-and-climate-model-evidence/
129662. Patrick 027 at 15:07 PM on 18 May 2009
        It's the sun
        Dan Pangburn (cont.) - "Without significant net positive feedback AOGCMs do not predict significant global warming." Approx. 1 deg C for doubling CO2 may or may not be considered significant; it is certainly a significant relationship of CO2 varies by a large enough amount. "Zero feedback results in 1.2°C from doubling of atmospheric carbon dioxide per p631 of ch8 of UN IPCC AR4 " That sounds about right. What I want to emphasize here is that the logarithmic proportionality of radiative forcing to atmospheric CO2 level has nothing directly to do with whether or not there are positive or negative feedbacks to radiative forcing or whether tipping points might be crossed as radiative forcing is changed. ----------- From the time scale dependence of feedbacks: There could be some exceptions, but the general tendency is for Earth's climate to vary the most in response to externally-imposed forcings with time scales ranging from perhaps many decades to perhaps hundreds of thousands of years, or something similar to that. Simplified hypothetical examples (with a qualititative resemblence to reality, but I don't actually know some of the real numerical values) to illustrate the point: Suppose at time 0, there is a sharp change in radiative forcing of + 4 W/m2 - perhaps from an increase in solar radiation absorbed over the Earth's surface (for an albedo of 0.3 and taking into account that the surface area of a sphere is 4 times its cross sectional area, a 4 W/m2 solar forcing actually requires about a 23 W/m2 increase in solar TSI, quite a bit larger than any variation known to occur outside the long-term solar brightenning over 100s of millions of years that is a characteristic of stellar evolution; recent solar TSI variations (over the period of time relevant to AGW) may be a tenth of that or perhaps less). BEFORE CONTINUING THAT, BACKGROUND INFO: ------------ (PS actually, often what is used for 'radiative forcing' is the tropopause level radiative forcing with an equilibrated stratosphere. I think this is the value that is close to 4 W/m2 (Actually maybe 3.7 W/m2, give or take a little) for a doubling of CO2 (and I think that includes the SW effects of CO2, which are much smaller than the LW effects but are present (CO2 can absorb some SW radiation). Radiative forcing at any level is the sum of a decrease in net outward (upward minus downward) LW (mainly emitted by Earth's surface and atmosphere) radiation at that level and an increase in absorbed SW (essentially all solar) radiation below that level; the climatic response involves changes in temperature that change the LW radiant fluxes to balance the forcing plus any radiative feedbacks that occur (which can be LW and/or SW). Variation in radiative forcing over vertical distance is equal to a radiatively forced heating or cooling. Top-of-atmosphere (TOA) radiative forcing is the sum of a decrease in LW emission to space and an increase in all absorption of SW radiation. An increase in solar TSI of 2 W/m2 results in a (globally averaged) TOA SW forcing of 0.35 W/m2 if the TOA albedo (the fraction of all SW radiation incident at TOA that is reflected to space) is 0.3. But the tropopause level forcing will be less than the TOA forcing because some of that 0.35 W/m2 is absorbed in the stratosphere - and it generally will be a larger fraction than the fraction of all SW radiation absorbed in the stratosphere, because solar UV fluxes are proportionately more variable than total TSI. An increase in the greenhouse effect involves increasing the opacity of the atmosphere over portions of the LW spectrum. Aside from LW scattering ... (which is minor for Earthly conditions, but can also contribute to a greenhouse effect in theory under some conditions (such as with dry ice clouds), but in a different way than atmospheric absorptivity and emissivity (by reflecting LW radiation from the surface or lower layers of air back downward); for Earthly conditions, scattering is much more important at shorter wavelengths) ..., each layer of atmosphere emits and absorbs LW radiation to the extent that it lacks transparency to radiation from behind it (in either direction). The surface also emits and absorbs LW radiation, almost as a perfect blackbody (but not pefectly; it does reflect a little LW radiation from the atmosphere back to the atmosphere). Along a given path at a given wavelength, Absorptivity = emissivity when in local thermodynamic equilibrium (a good approximation for the vast majority of the mass of the atmosphere and surface), where emissivity is the intensity of emitted radiation divided by blackbody radiation intensity (function of wavelength and temperature, and index of refraction, but that last point can be set aside for radiation in the atmosphere) for the temperature of the layer or surface, and the absorptivity is the fraction of radiant intensity absorbed along a path. As a path's optical thinckness increases either by geometric lengthening or by increasing density of absorbant gases or cloud matter, absorptivity and emissitivity both exponentially 'decay' from zero toward 1, or toward a lower number if there is reflection or scattering involved. Positive TOA LW forcing is caused a decrease in LW emission to space from increased opacity, which hides a greater portion of the (globally and time-averaged) larger LW fluxes from the (globally and time-averaged) warmer surface and lower atmosphere from space, replacing it with reduced LW fluxes from generally cooler upper levels of the atmosphere (the warmth of the upper stratosphere is in a very optically thin layer at most LW wavelengths and the thermosphere is too optically thin to have much effect). For relatively well-mixed gases (such as CO2), increasing concentration also cools the stratosphere by increasing the stratosphere's emmission to space and decreasing the upward LW flux that reaches the stratosphere. Thus, the tropopause level radiative forcing from an increase in CO2 is actually greater than the TOA level radiative forcing. (The SW forcing from CO2 absorption of SW radiation tends to heat the stratosphere, but the LW effect dominates. If there were an increase in SW absorption in the troposphere, this would add to tropopause level forcing, but it would (along with stratospheric SW absorption) reduce forcing at the surface.) Increasing LW opacity also tends to increase radiative forcing at the surface by increasing downward emission from the lowest (and generally, on average, warmest) layers of the atmosphere, by making them more opaque (they replace a fracton of the smaller LW fluxes from the upper layers and lack of LW flux from space with a larger increase in their emitted LW flux). Increasing solar TSI has a positive radiative forcing at the surface, which is smaller than that at the tropopause level because some SW radiation is absorbed in the troposphere. Other points: Volcanic stratospheric aerosols have a larger negative SW forcing at the surface and tropopause than at TOA because they absorb some solar radiation as well as scatter it. An increase in albedo at one level (at the surface or within the atmosphere) tends to produce a negative SW forcing, but it will be larger below that level than above to the extent that the increase in upward SW radiation above increases SW absorption (heating) above that level. An increase in absorption of SW radiation (such as by water vapor) only results in a positive TOA forcing in so far as it reduces the amount of SW radiation reflected to space (by intercepting SW radiation both before and after scattering), and will result in a negative forcing at lower levels. ---- The stratosphere has a low heat capacity and tends to reach equilibrium with radiative forcing on short timescales (sub-seasonal, as I recall). Radiative forcing with stratospheric adjustment includes changes in LW radiation within and from the stratosphere resulting from stratospheric temperature changes. This tends to reduce the difference between TOA and troposphere-level forcing from before stratospheric adjustment. It is useful to use tropopause-level forcing with stratospheric adjustment because the remaining climatic response will tend to be more similar among different forcing mechanisms (solar forcing warms the stratosphere and thus stratospheric adjustment increases forcing at the tropopause; the opposite is the case with CO2), although there can still be differences in efficacy (the climate sensitivity to global and annual average forcing, to one forcing agent relative to a reference forcing agent - for example, black aerosols on snow and ice (I am not 100% sure but I think the effect may be amplified because the warming is concentrated in regions where there is a strong positive feedback, resulting in greater global-average warming per unit global average radiative forcing), and also, perhaps how the effects of solar, volcanic, well-mixed greenhouse gas, and stratospheric ozone depletion forcings affect the circulation patterns of the stratosphere and troposphere and interactions between them...(NAM, SAM, circumpolar vortex); also, solar forcing can change the ozone level in the stratosphere - but so can climate change in general (temperature dependant chemical reactions, polar stratospheric clouds, circulation patterns that bring ozone from the tropics to the high latitudes and then downward). Why is tropopause level radiative forcing so important? In the global average, solar heating, although somewhat distributed among the surface and atmosphere, is displaced downward relative to the distribution of radiative cooling to space. In pure radiative equilibrium, this would be balanced by radiative fluxes among the surface and different levels of the atmosphere. However, the temperature gradient required for such radiative equilibrium is unstable to convection in the lower atmosphere. Thus, the climate tends to approach a radiative-convective equilibrium, in which, to a first approximation, a net convective flux (including surface evaporative cooling and latent heating upon condensation/freezing of water) cools the surface and heats the troposphere, balancing a net radiative heating of the surface and net radiative cooling distributed within the troposphere. Localized vertical convection, where it occurs, causes the troposphere's vertical temperature distribution to approach neutral stability - a temperature decline with height near the adiabatic lapse rate (the rate at which temperature decreases due to expansion of some mass of gas with decreasing pressure, in the absense of a heat flux into or out of that mass). Because of condensation, the lapse rate that applies (except near the surface, below cloud level) is the moist adiabatic lapse rate - it is less than the dry adiabatic lapse rate because of latent heating upon ascent. It diverges most when latent heating per unit vertical lifting is greatest - which is at higher temperatures (found lower in the atmosphere). Thus the moist adabiatic lapse rate varies over the globe and with weather conditions and seasons, though a good representative value is 6 or 6.5 K per km. Because radiative fluxes by themselves would drive the lower atmosphere toward being convectively unstable, the surface and various levels within the troposphere tend to warm up or cool off together in response to forcings - they are convectively coupled. Any increase in radiative forcing at the tropopause level corresponds to some change in radiative heating below the tropopause level. If this radiative heating is concentrated at some level, it will, without changes in convective heat fluxes, warm up that level, decreasing vertical stability above and increasing it below, thus slowing convective heat transport up to that level from below and increasing it from that level to above. Convection thus spreads the heating effect vertically throughout the depth that convection can occur. So the surface and all levels within the troposphere warm up by similar amounts. The warming may be a bit less at the surface because the moist adiabatic lapse rate decreases with increasing temperature (assuming the cloud base level (lifting condensation level) does not rise on average, etc., because the dry adiabatic lapse rate applies to convection below that level and it is larger and is less sensitive to temperature). Complexities of response: 1. This is complicated by spatial and temporal variations. 1a. The radiative forcing (and it's vertical variations) for any given change is not generally evenly distributed over space and time; just as each additional unit of any one substance (Gas or otherwise) will, beyond some point, have decreasing marginal effect, different agents can overlap with each other; additional CO2 will have less effect in cloudy and humid air masses (although the tropopause level forcing will depend much more on high level clouds and upper tropospheric humidity than low level clouds and humidity, since the CO2 in the cold air above a warm cloud or warm humid air mass will still block some LW radiation emitted from those warming layers; ... it is also worth pointing out for other reasons that reduction in CO2 radiative forcing by H2O vapor will be greater for surface forcing than for tropopause level forcing at least in part because H2O vapor relative concentration decreases generally exponentially with height, whereas CO2 is well mixed). ... There is, however, a (climate-dependent) average distribution of optical properties and their alignment with temperature variations, and thus radiative forcing, and the resulting temperature change takes time (short term weather phenomena can actually be described to a large extent without taking into account much radiation, except for the diurnal solar heating cycle). Clouds and humidity cannot realistically be rearranged relative to the horizontal and vertical distribution of temperature with infinite freedom; some things are linked by simple physics and some things correspond predictably because of the basic structure of the atmosphere and it's long-term climate (diurnal and annual cycles, land-sea and other geographical heating contrasts, the coriolis effect, Hadley cells, Walker circulation, monsoons, subtropical dry belts, midlatitude storm tracks, wind-driven and thermohaline ocean circulation, mesoscale convection phenomena, characteristics of variability in QBO, ENSO, NAM and SAM, PDO, AMO, etc, inertial oscillations, inertio-gravity waves, Rossby waves, ...). The global average radiative forcing by mathematical definition corresponds to a global average radiative heating rate below the level considered; if the level forms a closed surface, that heating, however horizontally distributed, cannot simply leak out without some change in climate itself - increased temperature to increase the net LW flux out to balance the radiative forcing + any radiative feedbacks. -------------- (When in climatic equilibrium, the Earth loses heat to space by LW emission at the same rate as it absorbs SW radiation (plus a TINY fudge factor for geothermal and tidal heating). This is a necessary but not sufficient condition for a climatic equilibrium, because climate change can in principle involve spatial and seasonal rearrangements of radiative heating and cooling and the convection/advection that balances them when averaged over fluctuations that could result in zero global-time average change in radiant fluxes. However, there are tendencies for the climate to behave in some ways and not others for any given set of solar, greenhouse, aerosol, geographic, biologic, and orbital (Milankovitch) forcings, etc.); a longer term equilibrium climate can be defined that includes patterns/textures of cyclical and/or chaotic shorter term variability, both from internal variability and from forcing cycles and fluctuations on the shorter time scales (annual and daily cycles, volcanic eruptions (when the statistics of such short term episodic events do not vary over longer time periods, then the resulting short term climate fluctuations can be incorporated into a description of longer-term equilibrium climate). -------------- 1b. There are daily, seasonal, latitudinal and regional, and weather-related and interannual variations in the distribution of convection and vertical stability in particular. Because much or most latent heating is associated with precipitation that reaches the surface, regions of descent are often dry; descent is also often slow over large areas and so adiabatic warming may be balanced by radiative cooling. Horizontal heat transport in the air from regions where much heat is convected from the surface can produce regions where the air is stable to localized overturning; this is especially true of polar regions in winter, where the surface and lowermost air is often or generally colder than some of the higher tropospheric air. Over land, there is a significant diurnal temperature cycle at and near the surface that is not matched by a similar cycle above - this is because a majority of solar heating is concentrated near the surface over a smaller heat capacity (in sufficiently deep water, there is a large heat capacity that damps short-term temperature cycling; finite thermal conductivity into soil and rock limits the depth available to supply heat capacity for radiative cycling as a function of frequency); thus, the daily high temperature near the surface is more coupled convectively to the temperatures in the rest of the troposphere than the nightime/morning low temperature. Horizontal temperature gradients can and do supply potential energy for large-scale overturning even when the air is locally stable to vertical convection, but this occurs more readily when the air is less stable; when air is more stable, a smaller amount of overturning is sufficient to eliminate horizontal temperature gradients by adiabatic cooling of rising air and warming of sinking air. There is a sort of large-scale convective/advective coupling of temperature change patterns, as either reduced horizontal temperature gradients or increased vertical stability will tend to reduce the large scale overturning (the Hadley cells, monsoons, Walker circulations, and the synoptic-scale circulations of strengthening baroclinic waves (the midlatitude storm track pressure systems and the jet stream undulations that correlate with them) - when any overturning on any scale increases, it reduces the tendency for more overturning by mixing heat horizontally and/or stabilizing the air to local vertical convection; a decrease in overturning has the opposite effect, so there is a tendency to approach an equilibrium overturning rate or at least fluctuate about such a rate; however, the spatial arrangment and category of overturning are a bit less constrained, allowing for internal (unforced) variability. And some circulation patterns (cumulus clouds and hurricanes in the short term, ENSO and some forms of storm track variability) can reinforce and strengthem themselves with feedbacks involving self-reinforcing distributions of latent heating and self-reinforcing momentum fluxes (but beyond some point, the midlatitude storm tracks are anchored to the way solar radiation varies with latitude, hurrican activity is regulated by sea surface temperatures and large scale circulation tendencies and temperature gradients, etc, and ENSO is in a way limited in magnitude by the width of the Pacific ocean - the warm water normally in the western tropical Pacific can only slosh back as far as the Americas)... The simple 1-dimensional globally representative model (describing everything in terms of a balance between vertical fluxes) also implies that the stratosphere is exactly in radiative equilibrium, but this is only approximately true for the global average. Some kinetic energy produced by overturning in the troposphere actually propogates (via Rossby waves and gravity waves) into the stratosphere and mesosphere and drives circulations there - that kinetic energy is converted to heat in the process, though it is a small amount - the larger effect, as I understand it - is large regional deviations from radiative equilibrium - sinking regions are adiabatically warmed, causing them to be warmer than the radiative equilibrium temperature, so they radiatively cool; rising regions do the opposite. (PS the QBO is a nearly-cyclical fluctuation of winds in the equatorial stratosphere that is driven by noncyclical fluxes of momentum from the troposphere, carried by a family of equatorial waves (including in particular Rossy-gravity and Kelvin waves); the cycle is self-organizing - the vertical distribution of winds in the stratosphere regulates where the momentum in different directions carried by different kinds of waves is actually deposited, so that regions of westerly and easterly flow alternately appear at higher levels and slowly propagate downward.) 2. While the temperature response of the surface and troposphere together tends to follow the (global-average) tropopause level forcing, the distribution of radiative forcing will affect the convection rates and thus the circulation patterns. However, except when a forcing is too idiosyncratic, the general tendency of the climate response to a positive tropopause level radiative forcing is: At the surface, greatest warming is in higher latitudes in winter where the albedo-feedback is strongest (the summer reduction of sea ice causes winter warming because the solar radiation is absorbed by water without much temperature increase, but this stored heat must then be released in the colder months before ice can reform). In the tropics, increased evaporative cooling is a negative feedback (at least over moist surfaces), but this is balanced by increased latent heating at higher levels - at low latitudes, the greatest warming will tend to be in the mid-to-upper troposphere because of the decrease in the moist adiabatic lapse rate. The stability of the air at high latitudes could help explain why high latitude warming is concentrated near the surface. Because of the opposite tendencies in the large-scale horizontal temperature gradients between lower and higher levels of the troposphere, the effect on baroclinic wave activity (midlatitude storm tracks) is not immediately clear, but more water vapor will be available for latent heating (the horizontal temperature gradient is a necessary condition for baroclinic waves but it is not their only fuel source), and perhaps the reduced vertical stability at higher levels might contribute to a poleward shift in activity (possibly with a positive cloud feedback on the storm tracks' subtropical flanks) - but there are other factors, including changes in the stratosphere and stratosphere-troposphere mechanical interactions (also affected by ozone depletion). The tropopause height will also increase (but is that more for greenhouse forcing than solar forcing?). Because of the dominance of the ocean in the Southern midlatitudes, the wind-driven upwelling of cold water (which, coming from below, will not warm much until the temperature signal of climate change has spread sufficiently through the deeper ocean), and the relative stability of much of the Antarctic Ice sheet (at least for a while) (as opposed to Arctic sea ice in particular), the near-surface high latitude polar warming will not be especially large relative to low latitudes in the the Southern Hemisphere, at least during the first few centuries (??). (Northern hemisphere land masses also have a seasonal snow albedo feedback.) The similarity of radiative feedbacks might overwhelm some differences in radiative forcings. The water vapor feedback in particular will have a much stronger radiative forcing at the surface than at the tropopause level (but the tropopause level water vapor feedback is sizable compared to the externally imposed forcing). Because of this, changes in vertical convection rates due to different forcing mechanisms might be more similar. (However, setting aside the radiative implications of the diurnal temperature cycle over land, the global average net convective cooling of the surface cannot get any larger than the direct solar heating of the surface; and precipiation (aside from dew and frost) can only balance evaporative surface cooling, which cannot exceed total convective cooling. Increasing the greenhouse effect will tend to increase precipiation but it cannot do so beyond such limits; aerosol cooling tends to decrease precipitation in a greater proportion to its effect on temperature, so balancing greenhouse warming with aerosol cooling would reduce precipiation in the global average. Where there is a regionally-concentrated forcing, such as by the Asian Brown Cloud, in which there is some tropospheric radiatively-forced warming but a negative radiative forcing at the surface, the temperature response at different levels on the same regional scale will not be coupled so much by convection; convection may be reduced in that region with perhaps some increase elsewhere depending on how much radiative forcing of each sign occurs, etc... The greenhouse effect tends to decrease the diurnal temperature cycle near the surface by decrease the relative importance of solar heating in the radiative energy budget - by increasing downward LW radiation by increasing LW opacity, and maybe by increasing LW radiation in both directions by increasing temperature (but only to the point that the net LW flux from the surface doesn't increase (??)). This is related to the larger diurnal temperature cycle found in higher elevations and clear nights with dry air. Wind can reduce the diurnal temperature variation by producing turbulence to mix heat downward at night when the surface is radiatively cooling. (Some feedbacks to global warming could regionally alter the surface temperature relative to temperature at other levels by affecting the rate of evapotraspiration.) (When there is sufficient solar heating on land, surface temperature is actually warmer than the air temperature just above it. The surface impedes effective convection, leaving thermal conduction and diffusion to transport heat and humidity from the surface to the air and within that very thin layer of air next to the surface. This doesn't destroy the convective coupling of surface temperature to air temperature, but it adds another chain in the link.) ------------ (to be continued...)
129663. Steve L at 13:53 PM on 18 May 2009
        Does ocean cooling disprove global warming?
        Reply to #5: I think the total amount of historical experience is also smaller with Argo than with XBT so, from a rhetorical standpoint, one may be able to argue that Argo isn't as reliable (still getting the kinks out) or wasn't as reliable early on. I work for an agency that uses hydroacoustics to estimate salmon runs -- the agency sometimes switches to newer technology. Of course, it does so to improve accuracy and precision, but early on in the transitional overlap period it would be a mistake to assume the new method is better, even though the agency expects that to eventually be the case.
129664. gv at 13:46 PM on 18 May 2009
        Does ocean cooling disprove global warming?
        #2 response [ Response: I believe Argo is designed to have more extensive coverage. The Argo homepage talks about how sparse measurements were before the Argo network was deployed (although they might be talking themselves up a bit on this page). ] So argo is at least designed to be a more accurate and extensive mesurement. So if argo dat is not coinciding with XBT data wouldnt it make sense to more rigorously question XBT data, rasther than the other way around ??? look i know nothing about argo or XBT or any of this- just trying to apply Popper and socrates a bit and see where it leads us
129665. Steve L at 12:57 PM on 18 May 2009
        Does ocean cooling disprove global warming?
        I feel woefully undereducated on this and should read the papers. But ... why tell you when I can show you?: The most striking feature of Figs 1 & 3, to me, are the seasonal pattern of ocean head content. The peak occurs in Autumn (southern hemisphere) every year. I imagine this is because most of the ocean is in the southern hemisphere and so has completed the half year in which it receives most of its solar energy. Two lazily considered ideas relevant to the discussion of the previous post: (1) measurement has to be pretty good for both Argo and XBT to resolve this signal (the signal is much stronger than noise on a seasonal scale), but it looks like Willis reconstructs this feature better than Leuliette in Fig 3; (2) if the total ocean heat content (estimated from the upper layer) can fluctuate this greatly among seasons, then surely it should be able to deviate from a monotonic annual increase. Both aspects of the first lazy idea argue for recent global cooling, I guess; the second lazy idea, if valid, would argue against it. Sorry for being so lazy! The other thing, though, that might be worth mentioning, is that steric sea level (Fig 4) doesn't seem to resolve any seasonal cycle. Does this suggest that resolution of the seasonal cycle is a poor criterion for evaluating this stuff or does it mean that Cazenave's method is less reliable?
        Response: I should've clarified in the figures but Figure 4 shows the steric sea level with the seasonal element removed. This enables you to more clearly determine the trend. Figure 3 does not have the seasonal signal removed. Steric sea level does have a strong seasonal cycle.
        
        In fact, Leuliette 2009 has an interesting discussion on the seasonal signal. They find that there is a strong seasonal signal of 8mm per year due to ocean mass change, peaking in the Northern Hemisphere summer. Eg - ice melt in the north. The steric sea level peaks in the Southern Hemisphere summer as most of the ocean is in the south, with an amplitude of 3.9mm. Both signals cancel each other out somewhat with the resultant global signal being around 4.2mm.
129666. Dan Pangburn at 12:50 PM on 18 May 2009
        It's the sun
        Ginckgo 382: The assessment using Control Theory described at 380 shows that atmospheric carbon dioxide level change, during the previous glacial period, had no significant influence on temperature change. The logarithmic decline of influence with increased concentration shows that CO2 has even less effect at the higher current level. This is all described further at the pdf linked from http://climaterealists.com/index.php?tid=145&linkbox=true
129667. gv at 12:31 PM on 18 May 2009
        Misinterpreting a retraction of rising sea level predictions
        oh and yes any hypothesis must be falsifiable that it means that there must be a clear testable means ( now or in the future) wherby you say that if X is true the hypothesis must be false. so how do we falsify AGW. what X must be true for AGW to be falsifiable.
129668. Dan Pangburn at 12:25 PM on 18 May 2009
        It's the sun
        Gord: What you describe, different ratios of temperature-change/CO2-change at paleo time vs. 20th century, corroborates that CO2 does not drive temperature. Another analysis that looks at atmospheric carbon dioxide level change vs. temperature change can be seen in a video at http://www.climate-skeptic.com/ . Correlation does not prove causation but lack of correlation proves lack of causation. The lack of correlation of the sequence of 30 year long up and down trends of temperature during the 20th century with the smoothly rising temperature proves lack of causation, i.e. that CO2 level did not drive temperature. Measurements made during the last decade also corroborate this. Since 2000, atmospheric carbon dioxide has increased 18.4% of the increase from 1800 to 2000. According to the average of the five reporting agencies, the trend of average global temperatures since 1998 shows no significant increase and for the seven years ending with 2008 the trend shows a DECREASE of 1.8 C°/century. This separation of trends corroborates the lack of significant connection between atmospheric carbon dioxide increase and average global temperature. I wonder how wide the separation will need to get before the IPCC and a lot of others are forced to realize that maybe they missed something.
129669. gv at 12:18 PM on 18 May 2009
        Misinterpreting a retraction of rising sea level predictions
        re # 2 "The Society keeps members informed on current news and activities through the regular distribution of the bi-monthly Bulletin of the Australian Meteorological and Oceanographic Society." That does not sound like a peer review journal to me. Sounds more like an academy mouthpiece. However, I do not know anything about the journal, this is just what i picked up at their website. re # 9 "Since the expectation of GW is the result of the framework theory, it has to be DISPROVEN to be invalidated." that is not how science works You generate a hypothesis you find supporting data if over the years ANY data is found that disproves the hypothesis. The hypothesis is wrong. or at least that is the scientific metyhod i have been used to in my line of work. Karl popper agrees.
129670. Ian Forrester at 12:10 PM on 18 May 2009
        Does ocean cooling disprove global warming?
        There is a good discussion on this on Physics Forums: http://www.physicsforums.com/showthread.php?t=311982 Just skip over the posts by Saul. The missing piece in this jigsaw is the amount of heat which is transferred into the deeper ocean. ARGO mostly measure up to about 700 meters. Some floats do go deeper but they are a small percentage of total. I think that most people have a hard time understanding that warm water can sink because simple physics tells them that warm water is less dense than colder water and should float. However, there is another contributing factor to density and that is salinity. As the surface waters warm and evaporate the water that is left becomes slightly more saline. As this keeps on recurring the increased density from evaporation causes an inversion (similar to what happens in lakes) and the surface water sinks to deeper depths carrying heat with it. This would occur on a cyclic basis but I have no idea how long it will take for the water to increase in salinity till it is dense enough to sink. Anyone have any thought on this?
129671. gv at 11:55 AM on 18 May 2009
        Does ocean cooling disprove global warming?
        Just trying to understand both points of view and to make up my mind..... for starters why was the argo system deployed ? was it more accurate than XBT ? Did it have more extensive coverage than XBT ? was xpt just running out of steam and needed replacement?
        Response: I believe Argo is designed to have more extensive coverage. The Argo homepage talks about how sparse measurements were before the Argo network was deployed (although they might be talking themselves up a bit on this page).
129672. Philippe Chantreau at 10:25 AM on 18 May 2009
        Does ocean cooling disprove global warming?
        Nice overview John. I still don't see where the logic is to say that oceans should be warming uniformly, without any kind of noise.
129673. Patrick 027 at 05:10 AM on 18 May 2009
        It's the sun
        ginckgo - good point. Dan Pangburn - Well, I don't see the value in using control theory if climate science has already advanced in every way beyond where control theory would be helpful. If control theory works, it must be more sophisticated than as suggested by your example, because you're results are incorrect. "Repeatedly during the last and previous glacial periods, a temperature increasing trend changed to a decreasing trend and vice versa. This is not possible if there is significant net positive feedback from temperature." This ignores the possibility that the temperature variations were externally forced. Positive feedback causes a cyclic variation in response to a cyclic forcing to be larger in amplitude than otherwise. It also ignores that feedback mechanisms work differently on different time scales: In the shortest time periods, climate change response to a high frequency forcing tends to be damped by thermal inertia (heat capacity), although if modes of internal variability (unforced fluctuations, such as QBO, ENSO...) resonate somehow with forcing ...(?) - but also, in doing analysis, one can not assume that any variation within some interval of the spectrum of frequencies is actually being excited by external forcings with those frequencies, because, though alterable by external forcings, some internal variability will occur without any fluctuating forcing (QBO, ENSO, NAM and SAM, AMO? etc...). When temperature does change in response to external forcing, nearly instantaneous positive feedbacks include water vapor. Clouds will also be a nearly instantaneous feedback, but it is not so clearly and/or generally positive. Over longer periods of time, seasonal snow can be a positive feedback. Sea ice changes can be a positive feedback. Generally over longer timescales (especially during cooling, because snow can only accumulate as rapidly as it precipiates, whereas melting and distingration of ice sheets can occur faster (with uncertainty)), glaciers and ice sheets, and changes in vegetation (forests vs grasses vs deserts, etc.) can be positive feedbacks. Changes in the more rapid portions of the carbon cycle (soil, vegetation, atmosphere, oceans) can also be a (positive) feedback. BUT over even longer periods of time, the very slow CO2 removal from the atmosphere by chemical weathering and geologic storage by generally slow organic C burial tends to balance geologic emissions of CO2. Changes in geologic emissions and changes in topography, land surface composition, and geography can force the atmospheric CO2 level, but resulting changes in climate tend to cause changes in chemical weathering so as to reach a new equilibrium CO2 level; furthermore, chemical weathering tends to act as a negative feedback to climate forcing by other causes (with some complexities - it depends on geography and rock composition, etc...). "With this knowledge and the knowledge of the logarithmic decline in effectiveness of added atmospheric carbon dioxide it is obvious that there is no significant net positive feedback from increased average global temperature." The logarithmic proportionality of radiative forcing to CO2 level has no direct bearing on the climate sensitivity to radiative forcing. "This IPCC prediction is probably still high because of faulty cloud parameterization, etc." Actually, cloud feedback in climate models is small and ranges from negative to positive; the dominant positive feedbacks are water vapor and albedo.
129674. ginckgo at 19:56 PM on 17 May 2009
        It's the sun
        How does the likely possibility that CO2 has not caused of every single change in climate in the past, preclude it from being a significant cause at the moment? You guys do see the fallacy in insisting that, considering the complexity of the system, right?
129675. Gord at 19:32 PM on 17 May 2009
        It's the sun
        Dan Pangburn - The Vostok Ice core data also show that the relationship between the Earth's temp and CO2 levels is probably linear relationship. I once plotted the the Vostok graphs on a computer using AutoCad and measured the change in temp vs the change in CO2 levels. Although this was just a crude approximation because I did not use actual data (just the graphs and only at a few points), the results showed that the change in CO2 divided by the change in temp was a constant (or very close). Because the change in CO2 divided by the change in temp is a derivative and produced a constant, this indicates that the equation describing the the relationship between temp and CO2 is probably linear. -------------------- The following is a re-post of what I posted on another forum a few years ago: --------------------------------- --------------------------------- The IPCC uses this formula for an approximate calculation of CO2's relationship to changes in W/m^2 forcing EXCLUDING AMPLIFICATION(I will call it delta F). delta F = 5.35 LN( C/Co) where LN is the natural logarithm, Co is the CO2 in ppm for a starting point, C is the CO2 in ppm for analysis and F is the forcing in W/m^2. The IPCC also uses a figure of 0.297 deg C change per each W/m^2. If we multiply both sides of the formula by 0.297 we obtain the relationship: delta T = 1.59 LN ( C/Co) where delta T is the change in temperature (in deg C). ------------------ A way to determine the "approximate" amplification factor that the IPCC uses for CO2. If the CO2 has gone from 1ppm to 290ppm (guesstimate for pre-industrial time) then delta T = 1.59 LN (290/1)= 9.02 deg C. The AGW'ers say the Earth has warmed by about 33 deg C due to the Greenhouse effect, so 33/9.02 = 3.66 must be the Maximum amplification factor possible. ------------------------ The Past and Future of Climate by David Archibald http://www.warwickhughes.com/agri/pastandfuture2.pdf Atmospheric CO2 vs Earth Temperature During the Ice Ages The Ice Ages (Figure 7) shows the biggest variances (interpolating) for Temp is 13 deg C (+3 to -10) and CO2 is 120ppm (180 to 300). This is about 330 thousand years ago. Using the above formula delta T = 1.59 LN (300/180)= 0.812 deg C The ratio for Actual CO2 change to Actual Temp change is 120ppm/13 deg C = 9.23 The "amplification factor" for CO2 would have to be 13/0.812 = 16.0!! Now look at a portion of the graph where the changes are less (eg. 215 thousand years ago) The variances are..Temp variance is about 3.2 deg C (-1.8 to -5) and the CO2 variance is about 30ppm (230 to 260) Using the above formula delta T = 1.59 LN (260/230)= 0.195 deg C The ratio for Actual CO2 change to Actual Temp change is 30ppm/3.2 deg C = 9.38 And, the "amplification factor" for CO2 would have to be 3.2/0.195 = 16.4 ! Clearly, the "amplification factor" varies so much, it is pure fiction....3.66 for the "Greenhouse Effect" vs about 16 for the Ice Ages! But, the MOST IMPORTANT thing this analysis shows is that, the CHANGE IN CO2 divided by CHANGE IN TEMP is really a CONSTANT (9.23 vs 9.38). The CHANGE IN TEMP divided by CHANGE IN CO2 is a DERIVATIVE that produced a CONSTANT. This means that the mathematical equation relating CO2 and TEMP HAS TO BE A LINEAR FUNCTION or close to it. Further, evidence of the LINEAR relationship is very apparent in the cyclical nature of CO2 vs TEMP in the Ice Ages graph. First, TEMP leads CO2 by about 800 years....CO2 follows TEMP LINEARLY! We know that the SUN's activity is cyclical in nature and CO2 absorbtion and release by the Oceans is governed by temperature. Temperature DRIVES CO2 production.....simple CAUSE and EFFECT. --------------------- If CO2 were assumed to "somehow" cause the the temperature changes (as the AGW'ers want us to believe) then: 1. It would HAVE to LEAD temperature not FOLLOW it. 2. The CO2 production (volcanos, bio-mass decay etc) would HAVE to occur in a "cycle" that produced the same sequence of events to produce the CO2 with the same regularity over about 400 THOUSAND YEARS!!! I would suggest that the probability of this happening is about ZERO. -------------------------- -------------------------- End of the re-post. Dan have you looked into this as well?
129676. Steve L at 15:07 PM on 17 May 2009
        Ice age predicted in the 70s
        I was struck by this week's skeptic article (by David Deming in "The American Thinker"), [http://skepticalscience.com/article.php?a=2327] finding it both laughable and inspiring, and it drew me back to here. One thing that surprised me a bit was Deming's claim that we don't know what causes ice ages. I thought it was Milankovitch cycles mostly (Deming says Ike Winograd disproved that). With the google I only found a Wunsch abstract [http://tinyurl.com/qg3bgw] that says orbital changes only explain 20% of the variance in climate records studies. Anyway, I'm curious to learn more about our understanding of ice ages.
129677. Dan Pangburn at 10:58 AM on 17 May 2009
        It's the sun
        The physics is the same, of course. However, most in the Climate Science Community are unaware of the science (which includes the physics) of Control System Theory. Control Theory should more properly be called Control Science, or better yet, Control Engineering since it has multiple practical common applications such as automobile cruise control, aircraft autopilot, missile guidance, electronic circuits, etc. etc. Control Theory is usually taught in mechanical, electrical and aeronautical engineering graduate school and is not in the Climate Science curriculum. Those who understand Control Theory have the knowledge to recognize that earth’s climate can be evaluated as a dynamic system with feedback. In the analysis, all of the minutia of weather and climate, whether known or not, get lumped together (in the control/plant which, by definition, includes all factors that influence average global temperature). The output, as archived in the ubiquitous Antarctic ice core data is extracted as temperature anomalies. Repeatedly during the last and previous glacial periods, a temperature increasing trend changed to a decreasing trend and vice versa. This is not possible if there is significant net positive feedback from temperature. It is not necessary to explicitly describe any of the factors in the control/plant (as used in Control Theory) to determine whether net feedback, if significant, is positive or negative. The average global temperature does not need to be known accurately just reasonable valid relatively. With this knowledge and the knowledge of the logarithmic decline in effectiveness of added atmospheric carbon dioxide it is obvious that there is no significant net positive feedback from increased average global temperature. Atmospheric/Oceanic General Circulation Models, AOGCMs, include the circulation effects of atmosphere and ocean. Climate Scientists use these global climate models to predict future climate. Although there may be no explicit input parameter for feedback in the AOGCMs, when used to predict future climate they incorporate features that result in significant net positive feedback. Without significant net positive feedback AOGCMs do not predict significant global warming. Zero feedback results in 1.2°C from doubling of atmospheric carbon dioxide per p631 of ch8 of UN IPCC AR4 (this 5.84 mb pdf file can be viewed and/or downloaded from http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Print_Ch08.pdf ). This IPCC prediction is probably still high because of faulty cloud parameterization, etc. Unless overwhelmed by other factors, an insignificant temperature increase of less than a degree Celsius, most of which has already taken place, is expected from doubling atmospheric carbon dioxide from the pre-industrial-revolution level of about 275 ppmv. See the pdf linked from http://climaterealists.com/index.php?tid=145&linkbox=true for a more extensive discussion and graphs.
129678. Quietman at 06:56 AM on 17 May 2009
        Volcanoes emit more CO2 than humans
        This is cut and paste from the original article that I can't locate: Although scientists understand the mechanics of El Nino, its origins have yet to be determined. The new theory [of the cause of El Nino] suggests that the primary mover behind El Nino is hot magma welling up between tectonic plates on the Pacific sea-floor. The upwelling magma heats the overlying waters enough to affect the ocean surface, initiating the cascade of events that brings on the wrath of El Nino. This, while not the same source says the same thing: Hot Vents and Global Climate Every two to seven years a climatic disturbance brings floods to California, droughts to Australia, and famine to Africa . Known as El Nino, it is essentially a warming of surface waters in the eastern Pacific near the equator. Although scientists understand the mechanics of El Nino, its origins have yet to be determined. Most believe that the interaction between the atmosphere and the sea somehow generates this climatic disturbance that wreaks havoc upon those regions of the world that lie in its path. But now a new theory on the origins of El Nino has been proposed and, surprisingly, it has very little to do with the atmosphere or the sea. The new theory suggests that the primary mover behind El Nino is hot magma welling up between tectonic plates on the Pacific sea-floor. The upwelling magma heats the overlying waters enough to affect the ocean surface, initiating the cascade of events that brings on the wrath of El Nino. http://www.platetectonics.com/book/page_20.asp
129679. Quietman at 06:34 AM on 17 May 2009
        Volcanoes emit more CO2 than humans
        I give up. When I first looked to find the cause there was one page of search results now there are hundreds.
129680. Quietman at 06:28 AM on 17 May 2009
        Volcanoes emit more CO2 than humans
        Here is a different view: As far as deep-ocean vents modifying the ocean temperatures, researchers now think that this source of heat does contribute to the long-term evolution of the ocean state. We can trace the chemical signatures of sea floor venting carried for quite a distance in the deep currents. Those traces are useful for estimating the deep flows, which are difficult and expensive to measure directly since they are so slow. However, we observe that the heating due to deep venting becomes diluted in the vast reaches of the abyssal ocean and therefore does not make quick changes in the ocean state. These affects are felt over decades or centuries, not on the relatively rapid time scale of El Niño. It is indeed tempting to look for simple causes of complex oscillations like the El Niño cycle. Unfortunately (or perhaps fortunately for those of us who like scientific challenges), it seems that the ocean-atmosphere system is well capable of generating these oscillations on its own, and the task now is to understand how this happens. Volcanoes and sea floor venting are part of the slowly changing background state to which phenomena like El Niño are added, and they increase the complexity of the task. http://www.pbs.org/wgbh/nova/elnino/resources/elninofaq.html Sorry, I still can't where the hypothesis is spelled out.
129681. Quietman at 06:16 AM on 17 May 2009
        Volcanoes emit more CO2 than humans
        The real cause of El Ninos is still obscure. However, the recent discovery of over 1,000 previously unmapped submarine volcanos rising from the seafloor in the eastern Pacific may lead to El Nino's source. The synchronous eruption of, say, 100 of these volcanos might warm the ocean around Easter Island a tad---just enough to warm the atmosphere above a bit---resulting in a shift of the high pressure area. The area of intense volcanic activity covers 55,000 square miles of sea floor where the Pacific and Nazca plates are separating. In addition to the active volcanos, many plumes of 800°F water gush from the sea floor in this area. The volcano-El Nino link is, therefore, not so far-fetched. (Nash, Nathaniel C.; "Volcano Group in Pacific May Cause El Nino," Pittsburgh Post_Gazette, February 14, 1993. Cr. E. Fegert) Comment. If submarine volcanos do cause the El Ninos, and the El Ninos are periodic, the submarine volcanism would have to be periodic, too. This implies an unrecognized rhythm in the earth's internal fires. - http://fusionanomaly.net/elnino.html
129682. Quietman at 06:12 AM on 17 May 2009
        Volcanoes emit more CO2 than humans
        Sometimes, and for reasons not fully understood, the trade winds do not replenish, or even reverse direction to blow from west to east. When this happens, the ocean responds in a several ways. Warm surface waters from the large, warm pool east of Indonesia begin to move eastward. Moreover, the natural spring warming in the central Pacific is allowed to continue and also spread eastward through the summer and fall. Beneath the surface, the thermocline along the equator flattens as the warm waters at the surface effectively act as a 300-foot-deep cap preventing the colder, deeper waters from upwelling. As a result, the large central and eastern Pacific regions warm up (over a period of about 6 months) into an El Niño. On average, these waters warm by 3° to 5°F, but in some places the waters can peak at more than 10°F higher than normal (up from temperatures in the low 70s Fahrenheit, to the high 80s). In the east, as temperatures increase, the water expands, causing sea levels to rise anywhere from inches to as much as a foot. But in the western Pacific, sea level drops as much of the warm surface water flows eastward. During the 1982-83 El Niño, this drop in sea level exposed and destroyed upper layers of coral reefs surrounding many western Pacific islands. http://earthobservatory.nasa.gov/Features/ElNino/elnino.php Yeah, I know that you really did want to know that either.
129683. Quietman at 06:08 AM on 17 May 2009
        Volcanoes emit more CO2 than humans
        ps Dr. S.D. Meyers and Dr. J.J. O'Brien. "Variations in Mauna Loa carbon dioxide induced by ENSO" Which I wanted to link for you has been surpressed by the new regime but is worth reading if you can find a bootleg copy.
129684. Quietman at 06:02 AM on 17 May 2009
        Volcanoes emit more CO2 than humans
        Note "Study: Volcanoes Unleash El Niño" http://dsc.discovery.com/news/afp/20031117/elnino.html is about the symptoms, not the cause.
129685. Quietman at 05:55 AM on 17 May 2009
        Volcanoes emit more CO2 than humans
        As I said chris, When I relocate the article I will post it here. I had not realized just how misunderstood this science was. This explains in part how the ocean drives the atmospheric currents known as Trade Currents. http://www7.nationalacademies.org/opus/elnino.html or http://www7.nationalacademies.org/opus/elnino_PDF.pdf It does not explain the thermocline fully however so I'll try to keep finding something on it's root cause that can be linked to.
129686. Patrick 027 at 03:16 AM on 17 May 2009
        It's the sun
        "Feedback Control Theory " How is that different from climate model physics?
129687. Gord at 22:52 PM on 16 May 2009
        It's the sun
        TrueSceptic - Yes, he is a sceptic. He is also a male, a human being, a consumer, a professor, wears pants, etc....does that hold any particular significance for you? Like I said... "I certainly agree with you that Feedback Control Theory is totally lacking in the field of Climatology." It seems that you somehow totally missed the point,...I was commenting about the curriculum of Climatology as discussed by Dan Pangburn. It should be evident to you that field of Climatology includes some "AGW sceptics"....they all share the same curriculum.
129688. Mizimi at 20:23 PM on 16 May 2009
        It's the sun
        Hmmm...astonishly honest as well....
129689. TrueSceptic at 10:43 AM on 16 May 2009
        It's the sun
        373 Gord, _I remember reading an article by a leading Climatogist (a Ph.D and AGW sceptic) that had "discovered" that Feedback and Control theory was being taught in the building next to his....the faculty of Electrical Engineering. He briefly described a simple single feedback loop control system. He seemed amazed that this technology even existed. He certainly had no idea that feedback and control system concepts have commonly been used electronic circuit designs since the invention of the vacuum tube._ Really? This is astonishing ignorance, and did you say he's a "sceptic"?
129690. Patrick 027 at 10:00 AM on 16 May 2009
        Arctic sea ice melt - natural or man-made?
        "A lot for you, nothing to the Earth. Everything is relative. " It was an analogy, Quietman. There are actually over 700 billion tons of C in the atmosphere in the form of CO2. Anthropogenic emissions could easily double atmospheric CO2. On a per molecule basis, CH4 is certainly a stronger greenhouse gas than CO2, and CO2 may be stronger than H2O vapor, but there's a lot more H2O in the atmosphere than CO2 (although there are variations in concentration such that H2O has less effect than it would if it were well-mixed), and much more CO2 than CH4. Etc. There is much less of any of these than there are N2 and O2, but N2 and O2 have little effect on LW radiation. Of course, the per molecule strength of a gas depends on overlap with other gases and with itself - these things depend on the concentration; for example, the radiative forcing of CO2 is roughly logarithically proportional to CO2 amount within a range of values. ------ "The science isn't settled." Depends on which part of the science. I never claimed that ever last piece of the puzzle had been fit together. What we know: Human activity has caused a dramatic and rapid increase in atmospheric CO2 and is still adding to that, pushing the atmospheric CO2 level to well above levels seen for hundreds of thousands of years. Human activity has also added other greenhouse gases. The mechanism of radiative forcing of climate is settled. Changes in greenhouse gas levels have made important contributions to climate change in the past, both as externally forced changes (volcanic activity and other geologic emissions, tectonically/mineralogically forced changes chemical weathering, changes in the C cycle due to biological evolution) and as feedbacks (orbitally-forced glaciations/deglaciations and monsoon changes, changes in solar TSI over 100s of millions of years, biological evolution, other climate changes). Water vapor and snow and ice albedo are important positive feedbacks. The best estimate of climate sensitivity from physics, paleoclimate, and the historical record is about 3 deg C per doubling of CO2 (or its radiative equivalent, adjusting for efficacy of different forcing agents), give or take roughly 1 deg C or so. Climate sensitivity from the paleoclimatic record can be problematic because climate sensivity could vary as a function of climate itself (and perhaps geography/geology and biological evolution); the climate sensitivity determined by greenhouse gas changes between preindustrial time and the last ice age may be larger than the climate sensitivity now because there is less ice sheet area available to melt/disintegrate and the snow and ice is more confined higher latitudes; however, Hansen's calculation of a 3 (+/- 1 ?) deg C for the radiative equivalent of a doubling of CO2 is actually calculated from the radiative forcing of greenhouse gases, ice sheets, aerosols, and land albedo changes from vegetation, and thus the climate sensitivity to greenhouse gas forcing and other anthropogenic forcings could be greater than that, as any ice sheet and vegetation responses would be feedbacks in AGW context. (Off hand I am not sure if sea ice albedo was included in Hansen's forcings; I think it was not. I inferred that nnow cover, along with water vapor and clouds, were treated as feedbacks. Snow cover would have extended to lower latitudes in the ice ages, but some higher latitude snow cover would be replaced by ice sheets, and the total area of seasonal snow might actually have been less (??), although it would have been at lower latitudes...)); however, there is evidence for a relationship even farther back in time than the last several ice ages, going back hundreds of millions of years; the Earth has been both warmer and cooler in the past. A persuasive case that there is some strong negative feedback missed by climate models is lacking. There are also both largely settled and unsettled aspects to what climate change means on the regional level. Greenhouse effect-driven warming will tend to warm the surface and troposphere but cool the upper atmosphere; solar forcing tends to warm both or cool both; volcanic aerosols can cause warming in the stratosphere while cooling the surface and troposphere. Any surface and tropospheric warming will tend to be enhanced in the mid-to-upper troposphere at lower latitudes (due to a moist adiabatic lapse rate feedback) and at higher latitudes near the surface (due to snow and ice albedo feedbacks and perhaps alsob because of the relatively larger vertical static stability in the air)(except, at least at first, in the Southern hemisphere due to the Antarctic Ice Sheet's stability, cold upwelling water driven by winds, and the dominance of water and lack of land in southern midlatitudes). Sea level will rise from thermal expansion of water and from melting glaciers and land ice (and not just until 2100); it will not be perfectly the same everywhere because regional sea level variations are caused by wind and temperature variations. Generally, a greater portion of precipitation will come in shorter time intervals at any given location. There is some expectation that midlatitude storm tracks will shift poleward, with drying trends on their subtropical flanks. Depending on how much more moisture the soil can hold in the spring from winter melt, there may be significant drying in midlatitude continents in summer in particular if extra precipitation in the winter is lost to runoff. There are significant costs to adapting to large, rapid, sustained changes into relatively unfamiliar conditions; if taken far enough, such change leads to mass extinctions. Ecosystems are stressed by such changes. The economy is an ecosystem and it depends in part on the larger natural ecosystems. Human society is obviously capable of rapid evolution, but this can still involve much pain, and that can be amplified by an evolved expecation of modern comforts, as well as population growth and politics (somewhat unlike in the stone age, it is not a simple matter to pack up one's belongings and just migrate; even if you are poor enough to carry all you own, borders and property rights get in the way). Buildings and infrastruture have been designed for conditions and will need adjustments. Agricultural productivity will decrease in the tropics; it may increase at first at higher latitudes, but only up to a point; tropical conditions are not kind to some valued food crops; the growing season cannot get any longer than a full year and growing season quality is important. Some crops are photoperiod sensitive. Breeding new crop varieties takes time and effort. There is great concern about fresh water availability as glaciers melt (regularity is important, not just total amount). Warming could increase risk and spread of some tropical diseases. Loss of biodiversity is a cost; biodiversity is a resource for new crops, drugs, etc. There is a great concentration of people near sea level. Uncertainty in climate change could itself be a cost because uncertainty hinders planning (there will always be uncertainty in the future climate, human effects or not, but presumably the total uncertainty is greater when there remains natural fluctuation and uncertainty in climate response to anthropogenic forcing). Even if adaptation were easier than mitigation (although it is not an either-or issue but a question of how much of each), it makes sense that the benificiaries of climate-change causing activities should pay the costs of climate change (the market response to that imposed price signal would tend to favor mitigating economic pathways - efficiency and clean energy, etc.). Even with various levels of uncertainty, there are actions for which an actionable level of inteligence will have been met. Even decades ago, it made sense to invest in clean energy and energy efficiency technology, at least to have it available to deploy with sufficient pace, as an insurance policy for the risk that global warming would be a problem. We have reason now to actually impose a price signal on emissions (or some other policy) to shift the economy towards greater demand of and investment in clean energy and energy efficiency as well as other emissions-reducing pathways. I do agree that there is room for debate about how large that price signal should be, because the science is not FULLY settled (it is likely it never will be FULLY settled).
129691. Mizimi at 05:16 AM on 16 May 2009
        Water vapor is the most powerful greenhouse gas
        Anybody read this http://www.landshape.org/dokuwiki/doku.php?id=introduction which is an outline of a new climate 'theory' by Ferenc Miskolczi (ex NASA mathemetician) and if so...any comments?
129692. Steve L at 05:15 AM on 16 May 2009
        A broader view of sea level rise
        #32 Ron: Hmmm, I thought you were asserting before that Argo disproved the concensus understanding of AGW. Now it seems you are saying that Argo and a bunch of other stuff suggest to you that AGW won't be "catastrophic". That seems like progress to me, but maybe I never knew what you meant. If you define "catastrophic" I'll be more likely to understand your perspective now. John, I thought I remembered a post of yours on effects of the solar cycle on temperature but I couldn't find it. Is it still around somewhere?
        Response: Here's the post on solar cycles. Note - it cites a recent paper that finds the solar cycle imposes a 0.18C signal on the temperature record. There are other papers that find around a 0.1C signal. I've since come to think its more likely to be the 0.1C signal as the strong signal Tung finds goes out of phase as you go further into the past.
129693. Mizimi at 04:57 AM on 16 May 2009
        It's the sun
        Relative to the 'it's the sun' thread.... icecap.us/images/uploads/REVISITINGTHEANALOGUEFORTHECOMINGICEAGE.pdf - presents an interesting view on AGW models and the results obtained from them.
129694. chris at 04:15 AM on 16 May 2009
        A broader view of sea level rise
        re #28 1. CO2 variability. a. Contrary to your assertion Ron, enhanced CO2 emissions during the last couple of decades do seem to be associated with enhanced atmospheric CO2 accumulation. We can inspect the atmospheric CO2 data: http://www.esrl.noaa.gov/gmd/ccgg/trends/ and find that the averaged yearly CO2 accumulation in the atmosphere for the decade 1990-1999 was 1.50 ppm per year and for the (not quite) decade 2000-2008 was 1.98 ppm per year. b. It shouldn’t be hard to “swallow” a relatively narrow range of CO variability since that’s what the evidence and our understanding of the carbon cycle indicates: (i) In a stable climate system with no change in external forcings (no volcanoes or, changes in solar output, greenhouse gases etc), there will still be some year on year variation in the atmospheric CO2. For example, in or shortly after El Nino years the CO2 levels rise due to heat and moisture stress in the tropical rainforest belts; in or after La Nina's tropical forests recover their growth and CO2 levels in the atmosphere drop somewhat. However that will just yield variation around a rather steady level. Atmospheric CO2 levels can't undergo extended continual unforced rises and falls without some sort of phenomenon external to the climate system, because there is a pretty fixed amount of accessible carbon in the short term carbon cycle. So on the decadal, centennial, millenial timescale the atmospheric CO2 levels aren't expected to change that much. In fact it's an indication of the rather steady nature of the accessible carbon in the short term carbon cycle that over tens and hundreds of thousands of years through numerous glacial-interglacial cycles, the atmospheric CO2 levels tend to return to interglacial values within a few ppm of 280 ppm. If one of the carbon pools (oceans/atmosphere/terrestrial) is perturbed, then the carbon will be redistributed. If deforestation and other land use changes reduces the carbon stored in the terrestrial pool and the atmospheric (and ocean) levels will rise. That seems to be the origin of much of the enhanced accumulation of CO2 in the atmosphere through the 19th century [N2O and methane rise follows a similar trajectory – see MacFarling Meure paper cited in post #23; see also the link on land use contributions to enhanced CO2 levels in Philippe Chantreau’s post #25]. Obviously if the climate system isn't stable and external forcings change (variation in solar output/major periods of volcanic activity and so on) then atmospheric CO2 levels will respond somewhat. That seems to be the origin of the small reductions of atmospheric CO2 through the period of the LIA….and so on… 2. You’ve misrepresented my statement:

        ”It's very easy to calculate that within a climate sensitivity right in the centre of the likely range (3 oC of warming per doubling of atmospheric CO2), the enhanced greenhouse warming during the two periods is 0.15 oC and 0.13 oC, respectively.”

        by contracting it to "the enhanced greenhouse warming during the two periods is 0.15 oC and 0.13 oC, respectively." …and then engaged in trashing your own misrepresentation! The point is that all else being equal, a rise in atmospheric CO2 from 286 ppm (1850) – 309 ppm (1940) should produce a surface temperature rise at equilibrium of around 0.3 oC within a climate sensitivity of 3 oC of warming per doubling atmospheric CO2. Since a large amount of science indicates that is the “best estimate” for the climate sensitivity under current conditions, we shouldn’t be surprised to find that the world seems to have warmed significantly during this period, with increasing effects on sea levels, glacial recession and so on. Of course in the real world all else very likely isn’t equal. A small enhanced solar forcing in the first half of the 20th century likely contributed to warming. Very significant volcanic activity in the late 19th/early 20th century, “knocked back” temperature rises temporarily…and so on. But we can hardly assert that temperature rises won’t follow from enhanced greenhouse gas levels, when the most likely scenarios from scientific evidence/analysis indicates that they should! And it’s not about “pro-AGWers” whatever that might mean – it’s about the science and its associated evidence. Small persistent changes in greenhouse gas levels are expected to produce re-equilibration of the climate system towards new temperatures, not because “pro-AGWers” “think” so, but because that’s what the evidence, and our scientific understanding of the greenhouse effect indicates. ..and a 9 ppm change in atmospheric CO2 is certainly measurable!
129695. NewYorkJ at 03:55 AM on 16 May 2009
        A broader view of sea level rise
        Ron Cram, You write "The assessment is also based on the climate sensitivity estimates by Schwartz and Chylek, Chylek's work on aerosols, Spencer's identification of a hew negative feedback over the tropics he identified as Lindzen's Infrared Iris Effect, and others." These assessments haven't held up too well. Comment on Chylek/Lohmann: http://www.clim-past.net/5/143/2009/cp-5-143-2009.html Basically, if you do some severe cherry-picking of data, you can find a lower climate sensitivity (or a much higher one as Annan illustrates). Comment on Scwhartz: http://www.jamstec.go.jp/frcgc/research/d5/jdannan/comment_on_schwartz.pdf As a result, Schwartz revised his estimate up about 50%, although not all the issues Annan et al found have been addressed. http://www.ecd.bnl.gov/steve/abstracts/HeatCapacityResponse.html Lindzen's hypothesis hasn't withstood the test of time, and has gone through various revisions. When one piece of data refutes a claim, it morphs until another piece is falsified. Chris Colose exposes some key problems with Lindzen's latest claims, and there's some clear evidence that Lindzen has a problem admitting error. http://chriscolose.wordpress.com/2009/03/31/lindzen-on-climate-feedback/ As for Spencer, what can I say? The UAH dataset has been revised upward more times than I can count. At one time he used his own flawed data to claim everyone else was wrong. The fact that he's working hard to find a negative feedback shouldn't surprise anyone.
129696. NewYorkJ at 03:40 AM on 16 May 2009
        A broader view of sea level rise
        Ron Cram, ""credibility" is not a factor under consideration" Really? You seemed to understand that a journal's reputability is important, given your comment in #4: "Roger Pielke, the ISI highly cited climatologist I referenced above" What changed? It's not really a choice for contrarians to publish in E&E. They do so because their studies are usually very weak and can't pass a single independent peer review in dozens of reputable journals. Keep in mind that this doesn't imply anything peer-reviewed is correct (not the specific purpose of a peer-review), but something that can't pass ANY valid peer-review is highly suspect. While it's plausible that a biased reviewer exists somewhere in some journal, alleging all of these journals are corrupt is a rather dubious charge that tends to hurt the credibility of the accuser, especially when they end up publishing a study in an uncited demonstrably political journal of like-minded skeptics. Publishing in E&E helps give them the false appearance of a better level of credibility than their study deserves - seemingly better than just posting it on their website. If you're a stickler for ad hominens, Climate Audit is the last place one would want to go. The individual of that site spends more time slinging mud at reputable scientists (the ad hominens you're referring to) than doing actual objective research, and your link is evidence of that. Also, your link does not support your claim of reviewer bias, as is generally the case with McIntyre's ramblings. Good scientists need to be able to acknowledge errors and move on without constantly alleging corruption and conspiracy from those who dare challenge them. McIntyre consistenly fails to meet this criteria. If you say that scientists aren't supposed to be advocates, by this criteria, what contrarian scientists would still exist?
129697. Patrick 027 at 03:06 AM on 16 May 2009
        It's the sun
        Re 372 - so you mean oxygen can indirectly cause cooling by affecting something else. Well of course, I have been aware that rising oxygen could lead to cooling by reducing the methane levels; however, I suspect this is a less significant effect once oxygen reaches some level of abundance and when methane's role becomes secondary to CO2 in climate-regulating greenhouse gases (except for short-term perturbations) - as far as I am aware, the O2 driven cooling by methane loss is thought to be potentially important in some Proterozoic ice ages, but I haven't heard anything about it being implicated in Phanerozoic ice ages. My impression has been that during the Phanerozoic, oxygen levels have not varied by an order of magnitude or more - instead reaching a peak of ~ 30 % or so some time in the Paleozoic (couldn't get much higher without forest fires consuming it), and it's now about 20 %, ...
129698. Ron Cram at 01:51 AM on 16 May 2009
        A broader view of sea level rise
        NewYorkJ, you are correct to think most researchers would prefer to publish in journals with a higher Impact Factor. I think I should explain why scientists sometimes choose to publish with E&E. Perhaps you have already heard the charge that skeptical papers are not well received by many journals. In most cases it has to do with the reviewers the editors chooses to review a paper. If you want, I can probably find advocacy quotes from editors of these other journals that would prove their motivation. It is a shame really, because scientists are not supposed to be advocates. I want to give you an example of what researchers are up against. Steve McIntyre, who has published in GRL and other journals, writes about a rejection notice he received from International Journal of Climate. http://www.climateaudit.org/?p=5978#comment-341365 Read Steve's comment and then a few comments following. You will begin to get a flavor of the kind of nonsense that goes on.
129699. Ron Cram at 01:28 AM on 16 May 2009
        A broader view of sea level rise
        Steve, I did read what Chris has written. I am not freaking out. I pointed out a few of the weaknesses with his argument. I hadn't the time then, or now, to deal with all of them. Your assessment that I have stepped back from my original position regarding Argo requiring a reconsideration of AGW theory is not correct. Loehle points out that there are reasons to question Argo data and I can accept that. But in my mind, the full accumulation of data is contrary to the claim AGW will be catastrophic. Argo is a very strong element of that but it is not alone. The assessment is also based on the climate sensitivity estimates by Schwartz and Chylek, Chylek's work on aerosols, Spencer's identification of a hew negative feedback over the tropics he identified as Lindzen's Infrared Iris Effect, and others. I have not found anything Chris has written as compelling. The only item you offer me is one I cited first and then Chris quoted back to me. It is one thing to be able to look up the numbers and another to be able to understand what they mean. A "pro-AGWer" is shorthand for a climate alarmist- one who strongly supports AGW theory. I would think the context would make that clear.
129700. Ron Cram at 01:10 AM on 16 May 2009
        A broader view of sea level rise
        NewYorkJ, your attack on the editor of E&E and Loehle's paper is completely ad hom. I'm sorry you do not understand that. In science, "credibility" is not a factor under consideration. The scientific method requires results to be reproduced. If results are reproducible, they are confirmed. If they are not, the paper is rejected. It is that simple.

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