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Comments 107301 to 107350:

107301. Karamanski at 01:17 AM on 9 October 2010
        Positive feedback means runaway warming
        Climate senitivity must be lower than the IPCC calculates. The ice age was ended by slight changes in the earth's orbit and rotation which melted some ice which enhanced the initial warming. Also a warming ocean gave up more carbon dioxide to the atmosphere further reinforcing the warming. These feedback loops continued until the present interglacial began. What I'm curious about is why did the warming stop. Wouldn't the warming have continued to feed on itself until all the ice sheets were gone and when the ocean ran out of carbon dioxide to emmit? Because of this there must be a negative feedback that we don't understand that well. Please explain this.
        Moderator Response: Try reading the "Advanced" tabbed page here. Is there some particular part of that, that you have a question about?
107302. Ken Lambert at 01:12 AM on 9 October 2010
        It's the sun
        KR #637 "1750 has perhaps the best (not perfect) chance of being at equilibrium of those three dates - 900 temps have a steady downward trend, part of the Little Ice Age, I suspect, while 1880 is in early industrialization with numerous forcing changes from early CO2. But as the various forcings move around, the climate can only follow, only hitting equilibrium if (a) forcings don't change for a period long enough for the oceans to catch up, or (b) forcings reverse and pass climate change going the other way." Well I agree with you that AD1750 at near the Maunder Minimum would be closest to equilibrium so the temperature 'trajectory' is close to zero. Having said that - you seem to then confuse Temperature trajectories with forcings. I notice that none of ya'll (Ned KR, kdkd) seem to accept my basic point that the area under ALL the forcing curves represents the total energy gained or lost by the Earth system. I have found a summation of the 10 Radiative forcings from your chart at #623, here: http://www.brighton73.freeserve.co.uk/gw/GISS_forcings.gif Now this is interesting because if you take the areas under the "Sum of 10 Forcings" composite curve - you can see that from 1850 to about 1915 all the area under the curve is negative. According to this The Earth system has lost energy from 1850 to 1915 so we should see cooling. There is no significant cooling in temperatures in this period - in fact all charts show increasing temperatures since 1850. Clearly the only forcing which could maintain temperatures and add energy to offset the negative area was Solar, but this has been 'chart zeroed' at 1850 and has negligible area under its curve. If a S-B IR cooling response curve was added which corresponded to a temp rise of about 0.1 degC (probably more)in that period then another -0.4W/sq.m of IR cooling would add to the negative area under the combined curves. The only conclusion is that Solar should not have been zeroed, but entered the chart in AD1850 at about 0.2W/sq.m+, in order to maintain a positive area under the composite curves to support a 0.1 degC+ warming in that period. The same argument follows on for the rest of the chart up to date.
107303. Berényi Péter at 01:00 AM on 9 October 2010
        Climate Cherry Pickers: Falling sea levels in 2010
        #69 TimTheToolMan at 21:11 PM on 8 October, 2010 I agree that accumulation of energy below the thermocline occurs primarily through conduction and my understanding is that the timeframes are measured in centuries. No, it is not he case. Thermal conductivity of water is 0.58 Wm^-1K^-1. To calculate power flux through a surface, one has to multiply it by temperature gradient perpendicular to that surface. Now, even at the thermocline temperature gradient seldom exceeds 0.04 Km^-1 (1°C difference in 25 m). Therefore in this layer power flux by conduction is less than 25 mW/m². However, as we go deeper, temperature gradient decreases rapidly; below 1000 m it is about 0.0007 Km^-1, implying a downward power flux of 0.4 mW/m² by conduction. On this rate it would take a million years to increase abyssal temperature by 1°C. A bit more than "centuries". On the other hand there is a geothermal heat flux from below at the bottom of oceans, some 100 mW/m² on average, that is, hundreds of times more than heating by conduction from above. So conduction is absolutely negligible, except perhaps in the very vicinity of the thermocline, but even there it fails to be dominant. If there were no poleward mass transport above the thermocline at all, the conductive power flux at it would lower the thermocline by about 20 m in a century. However, there is one, so average depth of the thermocline is pretty stable. It is mass transport alone that is able to influence heat contents of deeper layers in oceans on these short timescales, both wind or tide driven turbulent mixing and thermohaline overturning due to density differences. But I don't think this transport could exceed geothermal heating rate by much.
107304. Karamanski at 00:58 AM on 9 October 2010
        A detailed look at climate sensitivity
        When I said "only .8 degrees celsius" I was comparing the global warming so far to what is projected for the future. A rise of .8 degrees celsius a very steep increase relative to the known paleoclimate record. I also was not saying that warming has stopped. This decade was indeed the hottest on record and 2010 is on track to tie or exceed 2005 as the warmest calender year on record. Even though warming may continuing the rate of global temperature increase is steady and is not accelerating. From what I think, assuming that climate sensitivity isn't super high, I find it diffult to think that we will have a temperature increase of 3 degrees celsius by 2100. For example, thermal inertia might be much larger and slower than expected. I'm still very skeptical of the accuracy of climate models. For instance, they did not predict the halt in the increase of methane concentrations over the past decade. Arctic sea ice predictions by climate models are 40 years behind real observations. Please explain this.
107305. CBDunkerson at 00:46 AM on 9 October 2010
        It's the sun
        Ken #649: "The Earth's temperature in AD1750 which according to you and the AGW community is 0.8 degC COOLER than today's temperature." The 0.8 C figure is warming since the global temperature record began in 1880 AD. Most paleoclimate reconstructions have 1750 being somewhat cooler than that. That said, in 1750 TSI was around 1365.5 w/m^2. In order for TSI alone to cause a 0.8 C increase in global temperatures it would have to increase to about 1370 (a level never seen in the planet's entire history) rather than it's current level of about 1365. I pulled all of this TSI information from the 'Advanced' version of this article. Hadn't you read it?
107306. KR at 00:30 AM on 9 October 2010
        It's the sun
        Ken Lambert - I would agree, there is one TSI for one equilibrium temperature of the Earth, with all other variables held constant. Of course, if you change (for example) CO2 levels, the equilibrium temperature for a particular TSI will change, as the radiative efficiency of the Earth will change. But all other variables are not held constant. The other radiative influence changes are much much larger over the last 150 years. This is a multi-variate issue, and you're only looking at TSI vs. Temperature!!! So: - You insist upon equilibriums, when it's obvious from the temperature record that temps were not at equilibrium in 1750 (cooling slightly), - You don't recognize that existing forcings at any baseline date are incorporated in the temperature trajectory entering that baseline (your offset concerns), - You're going on about equilibrium TSI, when the TSI deltas are an order of magnitude less than the other forcing changes, - And most importantly, you're not (in any of the recent comments here, here, or elsewhere) including the CO2 or aerosol radiative deltas in your 'equilibrium' considerations. This horse has been flogged to death, Ken - you are hunting for a solar cause, you are not considering the relative magnitudes and importance of the radiative factors, and have ceased to add content to the discussion some time ago. I'm out of here...
107307. Eric (skeptic) at 00:23 AM on 9 October 2010
        The value of coherence in science
        in #40 BPP asks "A question that I have for any of the skeptics here is - What evidence would you find sufficient to change your mind about ACC?" My position on AGW has been consistent and coherent for more than a decade. I don't need any evidence for AGW (without the Catastrophe) because I believe the theory is sound. I don't even care if it is warming or cooling because I believe that natural factors modify sensitivity to AGW on various time scales, for example the blocking weather patterns which may be caused by lower UV. A question for you: what makes the CAGW position coherent? If the important catastrophe is stronger, more frequent storms and heat waves now, then sensitivity is low and the Greenland melting catastrophe is way out of range and not worth worrying about. If the more important catastrophe is Greenland melting, then there cannot be stronger and more frequent storms now because those lower sensitivity. In case someone wants to propose paleo evidence for sensitivity, there's a thread for that http://www.skepticalscience.com/detailed-look-at-climate-sensitivity.html with my assertion at #37. The bottom line is that a coherent CAGW theory can only choose one type of catastrophe, not both.
107308. Ken Lambert at 00:13 AM on 9 October 2010
        It's the sun
        Ned #645 Clearly the waste heat thread went pear-shaped after I left. Ned: "Yes, you do mention the OLR negative feedback that leads all forcings to decay towards 0 over time, as the planet's outgoing radiation increases or decreases. But you are still blindly ignoring this when you talk about your imaginary "equilibrium TSI". In fact, there is a continuous range of TSI values, any one of which can be balanced by a corresponding OLR value, leading to some particular stable temperature. There is no reason why one particular TSI value can or should be artificially promoted as the uniquely special equilibrium TSI that the Earth wants to be in balance with. If you still don't get this, someone else can take over, because I'm done." Ned, you have just confirmed exactly my contention about a 'unique' TSI corresponding to a particular 'Equilibrium' temperature. Let's repeat what you say above: "In fact, there is a continuous range of TSI values, any one of which can be balanced by a corresponding OLR value, leading to some particular stable temperature." Question: And can you guess what that particular temperature of interest is? Answer: The Earth's temperature in AD1750 which according to you and the AGW community is 0.8 degC COOLER than today's temperature. And what follows from that is that we have a TSI AD1750 corresponding to Temp AD1750. Pray tell me then Ned what is the value of TSI AD1750? And after you have done that you should than be able to advise what particular TSI value corresponds to an Earth temperature 0.8 degrees higher than that of AD1750.
107309. chris1204 at 23:32 PM on 8 October 2010
        Global warming impact on tropical species greater than expected
        John, I recall the lizard post rather well. I responded somewhat frivolously at the time. I thought this time I'd look into the business a little bit more closely and went behind a couple of pay-walls - a seriously worrying manifestation of skepticalcience addiction. The article you cited essentially models the metabolic theory of ecology, which suggests that larger species may have higher metabolic rates and that metabolic rates increase with temperature. Ectotherms which lack the capacity to regulate temperature would be especially vulnerable to increased temperatures for the very reasons you cited. The Wikipedia reference I've given above contains the same equations for metabolic rate as a function of temperature as Dillon et al. Entering 'temperature and metabolic rate' into Google yields over 800,000 hits. Most of the references dealt with hibernation but this article by Marshall & McQuaid (2010) was the first I came across dealing with temperature increases and metabolic rate: Warming reduces metabolic rate in marine snails: adaptation to fluctuating high temperatures challenges the metabolic theory of ecology The title is self-explanatory. Interestingly, the authors also note in their introductory remarks: 'Departures from the model's prediction of acute metabolic responses to temperature (the slope) have been shown for insects and arachnids...' The importance of this study lies in its demonstration of decreased metabolic rates via heart rate and oxygen consumption in aestivating (estivating) snails at temperatures between 30 and 40 degrees C. Aestivation comprises the 'summer sleep' or torpor experienced by a range of organisms to protect against heat stress and seems to be a widespread phenomenon in organism inhabiting marginal zones. In short, the behaviour of real organisms may differ in significant respects from what one would expect from the metabolic theory of ecology, which derives from Kleiber’s law, itself based on the posited physical and geometrical principles underpinning animal circulatory systems. Of course, the mere fact that I've come up with one paper identifying one organism (with references to the behaviour of some other organisms) whose behaviour does not accord with the metabolic theory of ecology doesn't automatically invalidate the concerns raised by Dillon et al. Dillon very properly cautions: '...plenty of real ectotherms have some ability to moderate their temperatures through behavior, such as darting under rocks to escape the sun. These measures have limits though, especially for small creatures, and actual biology — not just temperature — needs investigating. “You can’t assume that the temperature patterns tell you what the effects on biology will be,” he says.' The Marshall & McQuaid paper nevertheless suggests that the picture may indeed be very much more complicated at least for some organisms and ecosystems. However, the mere fact that these systems are so beautifully complex is reason enough to be wary of complacency about potential climate impacts.
107310. muoncounter at 23:29 PM on 8 October 2010
        It's the sun
        CBD, "the possible range of variation here is more than an order of magnitude less than GHG forcings. ... solar forcing for 2004-2007 ... was still less than the IPCC projected for this time period. " I thought those were the salient take-aways, especially in the context of 'its the sun' and 'its only the sun'. Funny how order of magnitude seems to get lost when discussing the role of various deltas.
107311. kdkd at 22:57 PM on 8 October 2010
        Skeptical Science housekeeping: Comments Gluttony
        HR #20 The moderation criteria seems to be based on the comments policy. I'm not 100% happy with the way that it all works, but it seems more effective than the nonsense at WUWTF for example. Hopefully in the not too distant future victims of comments deletion may get feedback from the deletionist as to why their comment was deleted.
107312. kdkd at 22:55 PM on 8 October 2010
        It's the sun
        KL #various Your "area under the curve" stuff is (from a statistical perspective) just a calculus-centric view of talking about regression models. We've done that to death elsewhere, and it doesn't confirm your over-complex, often illogical, statistically illiterate and difficult to ascertain argument. Come up with something new and I'll be happy to assess your arguments on its merits. This particular dead horse however is well and truely flogged.
107313. CBDunkerson at 22:33 PM on 8 October 2010
        Global warming is accelerating the global water cycle
        Kooiti Masuda #23: "Accordingly, the mean residence time of water vapor in the atmosphere becomes longer." If I understand correctly, this model result is a consequence of the same thinking (based on the Clausius–Clapeyron relation) that suggests a warming atmosphere will hold a greater amount of water vapor... rather than an independent verification (since higher evaporation + longer water vapor residence would perforce mean more total water vapor) of it. Do the Syed et al results bring us closer to validating the assumptions underlying these water cycle models? To clarify where I'm going... water vapor feedback is one of the major factors in determining 'climate sensitivity'. I'm wondering if water cycle monitoring and/or modelling are now precise enough to validate the projected positive feedbacks from water vapor. I know that Roy Spencer has recently suggested that an accelerated water cycle might actually lead to negative water vapor feedback due to precipitation outpacing evaporation; "The average amount of water vapor in the atmosphere represents a balance between two competing processes: (1) surface evaporation (the source), and (2) precipitation (the sink). While we know that evaporation increases with temperature, we don’t know very much about how the efficiency of precipitation systems changes with temperature. The latter process is much more complex than surface evaporation (see Renno et al., 1994), and it is not at all clear that climate models behave realistically in this regard. In fact, the models just “punt” on this issue because our understanding of precipitation systems is just not good enough to put something explicit into the models."
107314. Kooiti Masuda at 22:14 PM on 8 October 2010
        Global warming is accelerating the global water cycle
        johnd's question to me seems off-topic here, but I try to answer for once. I know that JAMSTEC does both observational and modeling studies about the Indian Ocean, but I am not better at explaining them than the official web site. The Indian Ocean Dipole is an element of interannual variability, something in the Indian Ocean like El Nino in the Pacific. "IOD positive" means sea surface temperature is low near Sumatra (high near Kenya). "IOD negative" is the opposite. While oceanographers tend to view that IOD and ENSO are distinct things, I rather view that both are parts of the Southern Oscillation in the broader sense as first envisaged by Gilbert Walker in 1920s. IOD, as well as ENSO, is not a directly important element of climate change (of longer time scales), but the trends in how often positive and negative IOD events occur can be a subject of climate change with many people's interest. I think that some basic characteristics of the Indian Ocean are more important in the issue of climate change (as well as water cycle). One is that the seasonal reversal of monsoon is the most distinct here. Another is that the intertropical convergence zone can appear on the either side of the equator here. Also, Madden-Julian oscillation (a mode of intra-seasonal variablilty) is usually generated in the equatorial Indian Ocean.
107315. TimTheToolMan at 21:11 PM on 8 October 2010
        Climate Cherry Pickers: Falling sea levels in 2010
        @Joe Blog I agree that accumulation of energy below the thermocline occurs primarily through conduction and my understanding is that the timeframes are measured in centuries. Accumulation of any energy can only occur with either an increase of energy input into the ocean such as might happen with a change in cloud cover or theoretically a decrease in energy lost from the ocean. This is the mechanism you hinted at with your suggestion increased LW radiation such as would happen with increased CO2, would decrease the LW radiation loss at the surface. But is this really the case? It might surprise most here that the science behind that assertion is at best weak and at worst non-existant. http://www.realclimate.org/index.php/archives/2006/09/why-greenhouse-gases-heat-the-ocean/ Explains the issue and you'll be hard pressed to find references to it elsewhere even though its the lynchpin behind AGW.
107316. CBDunkerson at 20:57 PM on 8 October 2010
        It's the sun
        muoncounter #641: Yes, I saw that report too. The bit about the magnitude of any solar change being "dwarfed" by the increase in CO2 forcing makes it somewhat of a minor issue AND the researchers note that the results need further verification... but it is certainly an interesting new wrinkle. Unfortunately, if validated it would essentially mean that we can't be sure about precise solar forcings prior to this kind of detailed spectral analysis. Is a solar minimum ALWAYS accompanied by higher output of VISIBLE light or was that the case for this particular minimum but not all? Are solar maximums characterized by DECREASED visible light or exceptionally increased levels? However, again... the possible range of variation here is more than an order of magnitude less than GHG forcings. The report also shows that while the solar forcing for 2004-2007 may have been greater than would have been suggested by looking at total solar irradiance (rather than a specific wavelength analysis)... it was still less than the IPCC projected for this time period.
107317. Ned at 20:41 PM on 8 October 2010
        It's the sun
        Ken writes: Try harder next time Ned. Not going to happen. After the fiasco of the Waste Heat thread, I'm no longer willing to expend indefinitely large efforts on repeatedly explaining the same points over and over again without any evidence of benefit. Yes, you do mention the OLR negative feedback that leads all forcings to decay towards 0 over time, as the planet's outgoing radiation increases or decreases. But you are still blindly ignoring this when you talk about your imaginary "equilibrium TSI". In fact, there is a continuous range of TSI values, any one of which can be balanced by a corresponding OLR value, leading to some particular stable temperature. There is no reason why one particular TSI value can or should be artificially promoted as the uniquely special equilibrium TSI that the Earth wants to be in balance with. If you still don't get this, someone else can take over, because I'm done.
107318. CBDunkerson at 20:32 PM on 8 October 2010
        A detailed look at climate sensitivity
        Karamanski #52: "Since 1880, global temperatures have only risin .8 degrees celsius." Only? You do realize that's the most extreme temperature increase, in both amount and rate, since the end of the last ice age right? "In order for global temperatures to rise by 3 degrees celsius by 2100, global warming would have to undergo a very rapid acceleraton. Apparently this isn't showing any signs of happening." It isn't? The actual temperature data seems to show that it is. The graph below shows both linear and quadratic 'best fit' trend lines against the GISS data. Note that the best quadratic fit is an increasing temperature slope. Not particularly surprising given that 2000-2009 was the hottest decade on record and 2010 is thus far the hottest single year on record. "Global temperature increases over the past decade have been on the low end of climate model projections." That's like saying, 'there were ten days at the end of Spring that were on the low end of average temperatures... therefor it seems unlikely that temperatures will increase this Summer'. You're looking at a short term fluctuation, no greater than half a dozen such since 1880, and ignoring the long term trend.
107319. jondoig at 18:43 PM on 8 October 2010
        Uncertain Times at the Royal Society?
        "Doubling CO will cause 2-4.5 °C global warming" Clearly you mean CO2 not CO. Also Joe Romm's post on this report at Climate Progress is worth a look. He argues the new report is dangerously conservative: "It doesn’t spell out simply and clearly what will happen if we don’t take action to reduce emissions nor does it spell out the plausible worst-case scenario (which is crucial to how individuals and societies actually make major decisions)."
107320. HumanityRules at 17:57 PM on 8 October 2010
        Skeptical Science housekeeping: Comments Gluttony
        Get personnal, graph the comments by poster, lets see who's posts generate the most heat ;)
107321. HumanityRules at 17:55 PM on 8 October 2010
        Skeptical Science housekeeping: Comments Gluttony
        #4 I was going to ask if the data had been adjusted for deleted comments. Look I'm curious about the moderation criteria. I had a few time consuming posts deleted recently which I thought were mainly if not completely science in content and which were around- if not on-topic (more on topic than some of the surviving posts anyway). Have you started deleting posts you consider plain wrong or misguided?
107322. chris1204 at 17:38 PM on 8 October 2010
        Global warming impact on tropical species greater than expected
        No doubt, as the tropics expand into temperate zones, some ectotherm populations may manage to migrate to new ecological niches. On the other hand, much will depend on the extent to which potential new habitats are physically accessible, the capacity of other plant and animal species forming part of their food chain to migrate with them, the extent of competition from species already present in new locations, and the extent of general habitat degradation. Clearly, a fascinating new variable in an array of challenges for our stewardship of the planet.
        Response: If I'd been more organised (and less forgetful), I would've referenced a recent blog post on observed local extinctions of lizards over the last 35 years.
        
107323. Tom Dayton at 16:45 PM on 8 October 2010
        A detailed look at climate sensitivity
        Whoops, I should have linked to a graph right here on Skeptical Science--a graph that includes as well some of the IPCC scenario projections for scenarios worse than constant emissions.
107324. Tom Dayton at 16:40 PM on 8 October 2010
        A detailed look at climate sensitivity
        Karamanski, the rate of CO2 emissions has been increasing since 1880, so the rate of CO2 concentration increase has been increasing, so the rate of temperature forcing from CO2 has been increasing, so the rate of temperature increase since 1880 has been increasing. Therefore the temperature increase rate can't be extrapolated as a linear increase from 1880 to the present. CO2 emissions will continue to increase. Perhaps the most convincing picture of the consequence is a graph of the temperature increase if CO2 emissions instead remained at their current level ("constant emissions"). That does not mean business as usual, because business as usual means the same amount of CO2 per unit of energy produced. Business as usual means an increasing amount of CO2 emitted, not merely an increasing amount of CO2 concentration resulting from constant emission. That's because increasing industrialization and increasing population will result in an increasing number of sources of and amounts of emissions. Business a usual will result in an increasing rate of CO2 emission. The lower bound of the business as usual scenario is the "constant emissions" scenario, in which the increasing number of sources is offset by reduced rates of emissions from each of the sources. That is the curve labeled "4. Constant emissions" in this figure reproduced at RealClimate. Even in that possibly unreasonably optimistic case, the temperature climbs dramatically because of the continued increase of amount of CO2 accumulating in the atmosphere. The business as usual case will be worse than that--much worse.
107325. Doug Bostrom at 15:50 PM on 8 October 2010
        It's the ocean
        Karamanski, I believe you're thinking of Keenlyside et al 2008 (full text, pdf) which includes Mojib Latif as a coauthor. The abstract is probably better to read directly rather than letting someone else paraphrase it. The key lies in the words "surface temperature" and regional variability, how much heat is available where we can measure it in various regions of the surface temperature network and different regions of ocean surface. Keenlyside predicted a regional cooling in the North Atlantic area caused by circulation changes in the North Atlantic ocean, sufficiently strong as to cause a change in the overall surface temperature trend, even as other areas of the globe continued to warm. Behind all this is no change in the total amount of energy being retained on the planet, rather a change in distribution. Popular press treatments of this paper conveyed the impression that warming was going to stall or even that the Earth was going to cool, which is wrong in terms of energy being retained on Earth during the period covered by Keenlyside's prediction. Richard Wood explains this in a commentary at Nature accompanying Keenlyside et al: [Keenlyside's] starting point is the ocean. On a time scale of decades, this is where most of the ‘memory’ of the climate system for previous states resides. Anomalously warm or cool patches of ocean can be quite persistent, sometimes exchanging heat with the atmosphere only over several years. In addition, large ocean current systems can move phenomenal amounts of heat around the world, and are believed to vary from decade to decade. Wood goes on, regarding the extent of the predicted cooling: The authors use their model to predict that the MOC will weaken over the next decade, with a resultant cooling effect on climate around the North Atlantic. Such a cooling could temporarily offset the longer-term warming trend from increasing levels of greenhouse gases in the atmosphere. That emphasizes once again the need to consider climate variability and climate change together when making predictions over timescales of decades. On a parenthetical note, it's fun when scientists bet money on validation. Some climate researchers found Keenlyside's analysis and forecast sufficiently debatable as to offer a bet on the outcome.
107326. KR at 14:57 PM on 8 October 2010
        Global warming impact on tropical species greater than expected
        Not terribly surprising, actually. Tropical species are adapted to much more consistent conditions than temperate or arctic species.
107327. KR at 14:45 PM on 8 October 2010
        It's the sun
        *Including* the offset you are so concerned about?
107328. KR at 14:42 PM on 8 October 2010
        It's the sun
        Ken Lambert - You haven't responded to my latest post. Do you understand that the 'baseline' is the starting point for forcing deltas, and that the incoming trajectory for temperature incorporates the forcings existing at the baseline timepoint? The offset you are so concerned about?
107329. scaddenp at 13:59 PM on 8 October 2010
        It's the sun
        RC have a post up on it - which is basically "wait and see, we think it is instrument error".
107330. Stephen Baines at 13:53 PM on 8 October 2010
        Global warming impact on tropical species greater than expected
        BTW that's Deutsch 2008. I'm bad with dates...Must be my age.
107331. Stephen Baines at 13:51 PM on 8 October 2010
        Global warming impact on tropical species greater than expected
        Interesting. Hey John. I sometimes use a paper from PNAS by Deutsch et al 2007 in class in my physiology lectures as a good example of how to apply physiological principles (in this case temperature vs performance curves) to ecological problems. That paper also finds that tropical insects, and perhaps tropical cold-blooded species generally, are likely to be more susceptible to increasing temperature than temperate species, even though the temperature change is likely to be greater at high latitudes. The reason in that case has to do with adaptation to climate variability. They show that tropical species are operating much closer to their optimum and maximal temperatures, presumably because low seasonal variability in temperature in the tropics allows them to be more finely tuned, metabolically speaking, to their environment without too much risk of experiencing lethal temperatures. Temperature species, on the other hand, operate well below their thermal optima and maxima, presumably to avoid the possibility of experiencing lethal temps. The much lower margin for error in tropical species causes their population growth to be negatively affected by predicted temperatures, while higher latitude species actually experience an increase in population growth initially in response to warming.
107332. adelady at 13:45 PM on 8 October 2010
        The value of coherence in science
        chrisc, et al Post-normal science as defined reads ".. appropriate for cases where "facts are uncertain, values in dispute, stakes high and decisions urgent .." I really dislike the use of this term. To me, it's dog-whistle in the sense that "we-don't-know-enough" = "facts are uncertain". The examples given are for surgeons being forced to deal with life-threatening injuries despite not knowing the full extent of those injuries or engineers faced with a collapsing dam or bridge not knowing exactly how the original fault arose. With climate science the same does not apply. It's in the same position as any other branch of science - it is simply not possible to know every single thing that might possibly have some marginal impact on the body of knowledge. But the core body of knowledge is substantial and proven. The accumulating data merely supports and expands the current science, occasionally there's an interesting unexpected item. Those are mainly big things, like the speed of Arctic ice loss, with a few small ones, mainly in the area of regional effects which are specific consequences rather than core to the science itself. (And all science would stop in every field if it was impossible to find out anything new or interesting.) There are questions about just how much faster sea level and temperatures will rise, how badly acidification will impact certain regions or food items, lots of questions. But the core issues of 1)the climate is changing by warmong, 2)the observed change is much faster than any known previous warming, 3)the cause of this change at this time is CO2 released too fast from carbon sinks, - not one of those core facts is in question. So I'd strongly dispute climate science as meeting the definition of post-normal science.
107333. muoncounter at 13:24 PM on 8 October 2010
        It's the sun
        Has anyone a comment on this report of variations in solar output during 2004-2007? "The amount of visible radiation entering the lower atmosphere was increasing, which implies warming at the surface," says atmospheric physicist Joanna Haigh of Imperial College London, who led the research, published in Nature on October 7. But the change from 2004 to 2007 in the sun's output of visible light, and the attendant warming at Earth's surface of 0.1 watt per square meter, is roughly equivalent to the overall forcing of the sun on the climate over the past 25 years—estimated by the U.N. IPCC to be an additional 0.12 watt per square meter. That suggests scientists may have overestimated the sun's role in climate change. Regardless, the solar change is dwarfed by the impact from the extra heat trapped by CO2 alone since 1750: an additional 1.66 watts per square meter, an effect that other greenhouse gases, such as methane, strengthen further. In other words, whereas the new satellite measurements call into question computer models of solar output, it does not change the fundamental physics of human-induced global warming.
107334. Joe Blog at 13:21 PM on 8 October 2010
        Global warming impact on tropical species greater than expected
        Ahhh, it is about cold blooded species.
107335. Joe Blog at 13:18 PM on 8 October 2010
        Global warming impact on tropical species greater than expected
        Im a lil confused by this i have to admit...Well the metabolic rate in warmblooded animals should increase with cold...not warmth, it takes more energy to maintain our core temperatures... Cold blooded is the opposite o course, ill have to have a read o the paper;-)
107336. johnd at 12:51 PM on 8 October 2010
        Global warming is accelerating the global water cycle
        Kooiti Masuda at 12:26 PM, Kooiti, even though it may not be within your direct field of interest, when the topic allows, it would be of interest to hear your perspective on the research being done at JAMSTEC on the Indian Ocean, and the IOD, and how it all fits into our current understanding of regional and global climate.
107337. chris1204 at 12:47 PM on 8 October 2010
        The value of coherence in science
        Oh and thanks also JMurphy :-)
107338. chris1204 at 12:46 PM on 8 October 2010
        The value of coherence in science
        Thanks for your responses Ned, Mike, Phila, & Doug, all of which are very helpful and thought provoking. I'll follow up the links you've suggested. Ned comments about 'self-organisation' of groups, saying 'I think this is a bad thing. I would like to break this pattern.' I can only say enthusiastically, 'Hear, hear!!!' Phila @ 54, I don't think I'm comparatively unique - if I did, you would be very right to find this troubling. I'm in a line of work which requires a high degree of self-reflection but whether I do it particularly well or not is another question. I often fail at it - just ask my wife and children :-). I'm good at talking about self-reflection, which is not the same thing, as you so rightly point out :-). Doug: 'Reflexive categorization itself is presumed to be a negation of the worth of research, but it's not.' Again, you're absolutely right. And for all my grumbles about the 'post-normal' aspects of a lot of medical research, I can't see any viable substitute for our present system. The only value in labels such as 'post-normal' (I actually think it's a rather clumsy term and wish there was a more neutral label) lies in understanding the limitations of a research paradigm. Understanding the limitations of a research paradigm is not the same as to dismiss it. The research may still be very useful so long as we retain the capacity for requisite discernment. For example, Jenner's popularisation of vaccination (he did not 'invent' it) took place in the setting of zero understanding of our immune system. Nevertheless, none would question the value of his work or that of Pasteur which saved millions of lives and served as a springboard to our current knowledge explosion in immunology. At the same time, there would have been numerous interventions back then which would have looked broadly similar and yet were singularly useless. Some such as homeopathy remain popular even today.
107339. Albatross at 12:26 PM on 8 October 2010
        Global warming is accelerating the global water cycle
        Johnd @22, I get back to you tomorrow, have plans tonight.
107340. Kooiti Masuda at 12:26 PM on 8 October 2010
        Global warming is accelerating the global water cycle
        It is difficult to evaluate global water cycle based on observational data. The achievement of Syed et al. is great. (I am a bit ashamed that I have not published original results though I am purported as an expert in this field of science.) But it is a piece of science in action and it should not be considered as something definite. There is asymmetry in the situation of climate science. From theories, it is easier to discuss global phenomena. From observations, it is easier to discuss local phenomena. *** In the world of numerical climate models (which are based more on theories than on observations), the situation is clearer, but again somewhat confusing. I have watched simulations by all global climate models which participated in "CMIP3" collaboration (the same as which was used in IPCC AR4) in a certain scenario (A1B) of greenhouse gas emission for the 21st Century. As the global mean surface air temperature rises, global mean precipitation and global mean evaporation (which are nearly equal to each other) increase in all models. But the relative rate of increase is slower than that of global mean water vapor content in the atmosphere. Accordingly, the mean residence time of water vapor in the atmosphere becomes longer. In terms of mass flow per unit time, the water cycle accelerates. But in terms of efficiency of recycling, the water cycle decelerates. The results seem robust as far as the current generation of climate models are concerned. There is a small possibility that all models err similarly, because all models use hydrostatic approximation and (various kinds of) cumulus parameterization.
        Moderator Response: Not to cause embarrassment or red ears, but let's acknowledge how privileged we are to have Dr. Masuda pay us a visit. We can best do so by applying our very greatest effort in formulating any questions we may have regarding the topic of this thread, the global hydrological cycle.
107341. Karamanski at 11:46 AM on 8 October 2010
        It's the ocean
        A paper by Mojib Latif predicted that changes in ocean circulation in the Atlantic could cause the rise in global surface temperatures to stall for a decade or two. How exactly would changes in ocean circulation cause global warming to temporarily slow for a decade? Is this related to the Atlantic Multi Decadal Oscillion? Would this have any effect on ocean heat content? I've been curious about this for a long time. Please explain this.
107342. Ken Lambert at 11:43 AM on 8 October 2010
        It's the sun
        "You claimed that a graph showed that "the actual value of the Solar forcing is in the range of 0.3 - 0.5W/sq.m and ongoing since about AD1700" That was a highly misleading statement, since the actual graph showed it not even rising up to 0.3 -- the bottom end of your claimed range for the past three centuries -- until the 1930s." You are exaggerating and splitting hairs Ned. Some of the proxies are higher than the black line average and some naturally below. The highest is about 0.4W/sq.m circe AD1750. I can dig up the actual numbers from the site and check it - but for now 0.2 - 0.5 is good enough. My point about the area under the curve being the total energy is the critical one. "Ken, there is no unique "equilibrium TSI where the Earth neither warms nor cools due to Solar". No such number exists! There are infinitely many possible values of TSI which would produce neither warming nor cooling of the Earth. I keep making this point and you keep ignoring it." Again - such a number MUST exist for the pre-industrial (unforced by AG forcings) Earth. Conservation of mass would indicate that the Earth has a constant amount of dirt, water (in ice of liquid form) air etc etc. There would be an overall function which takes into account the specific heats, latest heats etc of the whole Earth system subject to warming by external forcings. "I assume you are also not including the climate response forcings (IR cooling and WV feedbacks) in this analysis which net currently is -0.7 W/sq.m and would give a significant energy loss area under its curve to add to the Solar and All Other above." I have already mentioned S-B IR cooling plus feedbacks as being added to the other forcings which will bring the system toward equilibrium. S-B cooling is currently -2.8W/sq.m and proportional to T^4 so will rise rapidly with actual temperature increase - closing the forcing gap (unless WV and ice feedbacks rise faster) The S-B IR + WV response curves should be included in these 'AG Radiative Forcing' charts with Solar so the viewers can get the real picture of the overall warming curve for the planet. Try harder next time Ned.
107343. Karamanski at 11:32 AM on 8 October 2010
        A detailed look at climate sensitivity
        I agree entirely that humans are causing global warming, and that solving the problem should be our highest priority. However, I am very skeptical of the accuracy of climate models and their global temperature projections for the 21st century. I think a global temperature increase of 3 degrees celsius is a bit wide of the mark. Since 1880, global temperatures have only risin .8 degrees celsius.In order for global temperatures to rise by 3 degrees celsius by 2100, global warming would have to undergo a very rapid acceleraton. Apparently this isn't showing any signs of happening. Global temperature increases over the past decade have been on the low end of climate model projections. I'm not saying that warming has stopped, but I am saying its falling short of climate model projections. I find it very hard to believe that we will have a global temperature increase of 3 degrees celsius by 2100. Could you please explain this to me?
107344. johnd at 11:23 AM on 8 October 2010
        Global warming is accelerating the global water cycle
        Albatross at 09:53 AM, these maps from BOM perhaps best illustrate the difference. Note that it is E as measured by pan evaporation that is charted. I think that pan evaporation should exceed rainfall is something that should be self evident. Given that pan evaporation appears to be the only actual standardised physical measurement, at some point all other calculated values of evaporation under defined conditions such as Evapotranspiration (ET) must at some point be referenced back to such physical measurements. I note in the explanation you provided, it is E that is referred to, not ET, so I assume that it is being used to define the same E as BOM do, though that is not clear.
107345. pbjamm at 11:23 AM on 8 October 2010
        Climate Cherry Pickers: Falling sea levels in 2010
        @ TimTheToolMan adelady asked you @40: "Where exactly will the heat to drive the next el Nino come from?" @43 you respond: "In answer to your question or rather to put it into perspective, the heat you speak of could accumulate in a matter of days if not hours." If this is so, then why does it not at all times? You say @47 that only a tiny portion accumulates per day. Please take the time to explain the mechanism at work here.
107346. The Skeptical Chymist at 11:09 AM on 8 October 2010
        The value of coherence in science
        @ Chris There are some ~500-600 comments on that Realclimate thread making it hard to find the relevant exchanges, but the Climate Progress post linked to by JMurphy @ 57 is a copy/paste of guts of it.
107347. Joe Blog at 10:53 AM on 8 October 2010
        Climate Cherry Pickers: Falling sea levels in 2010
        Ahh, after having a bit o a better read o the comments, i see Goddard didnt apply inverse barometer, so apple n apples then...
        Response: The data with the inverse barometer applied is a "better" signal - if you don't filter out the atmospheric pressure effects, you get a much noisier signal with lots more ups and downs (much better for cherry picking). In this case, Goddard opted for inverse barometer not applied so I thought rather than get bogged down in discussion of inverse barometers, I just plotted the same data he used.
107348. scaddenp at 10:49 AM on 8 October 2010
        Climate Cherry Pickers: Falling sea levels in 2010
        Should also add, over longer time scales, conduction and mass transport can store heat deeper into the ocean. These processes are slow movers of heat however so surface just warms first, limiting how much you can store in a day.
107349. michael sweet at 10:31 AM on 8 October 2010
        Carbon Dioxide - Everyone's Favorite Pollutant
        RSVP: I have seen no scientific arguments that we should ban gasoline, or even coal, if they figure out a way to keep the CO2 (and other pollutants) out of the air. I think carbon sequestration is unlikely to be economic for coal use, but if it is more power to them. Your argument is absurd on its face- look at it being compared to cigarettes. You need to rethink what you are trying to achieve. Your claim, on a scientific blog, "It doesn't take facts; just common sense" makes you appear a fool. Changing to "why don't we label coal a pollutant" is no better. We all remember your previous similar arguments and your lack of understanding of the basic science. If you want to convince anyone to consider your arguments they need to be fact based to succeed on this blog. Perhaps if you understood the science you would change your opinion. The information you need is on this site if you choose to read it.
107350. scaddenp at 10:23 AM on 8 October 2010
        Climate Cherry Pickers: Falling sea levels in 2010
        TTTM - I was thinking about heat capacity, conductivity etc. Irradiate a surface and it heats till temperature is such that blackbody radiation matches incoming radiation. You arent asking me to prove that? The storage of energy for a material before that temperature is reached depends it heat capacity. Straightforward for land, but for sea, convection, transport of heat by mass flow, etc. will also affect this (the nebulous thermal properties). Conduction also moves heat away from the irradiated surface so this also has be figured in.

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