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Comments 118701 to 118750:

118701. Doug Bostrom at 02:45 AM on 27 May 2010
        Greenland rising faster as ice loss accelerates
        Further to Phila's remarks on "alarmists", "warmists" and the like, this research was done and will continue to be done quite apart from any ideological considerations; folks such as Phil Jones are nice examples of somebody's curiosity leading them inadvertently into the limelight, as Pielke Sr. recently remarked. The muse researchers are following is mostly a private spirit. Public reactions to research findings are quite divorced from motivations leading to new discoveries; Charles Darwin did not set out to upset Christian orthodoxy regarding creation but inadvertently blundered into that controversy. The exact behavior of ice sheets, the response of the crust to changes in mass balance, all these matters and more will be scrutinized to a fare-thee-well not because researchers are grinding some axe but instead due to the human inclination to resolve mysteries. That may be a hard thing to believe but I think most scientists would largely agree.
118702. Phila at 02:33 AM on 27 May 2010
        Greenland rising faster as ice loss accelerates
        Wes, "Hard to imagine our hydrocarbon-based economy surviving the next 40 years of technological evolution." It was hard to imagine in 1970, too. And yet, here we are.
118703. chris at 02:33 AM on 27 May 2010
        Robust warming of the global upper ocean
        Ken Lambert at 23:46 PM on 26 May, 2010 "The mechanism of heat transfer to the oceans from the atmosphere has always been unconvincing." Nope. An unconvincing variety of "common sense" doesn't "trump" a century of understanding of the thermodynamics of radiative heat transfer! Remember that for each 10^22 joules of energy added to the top 700 metres of the oceans, this region of the ocean (top 700 metres) warms by ~ 0.01 oC [*]. Therefore year on year variation of upper ocean heat content is very difficult to measure and yearly averaged measures of ocean heat content have a considerable associated error (as is apparent in the error bars in the data in the figures in the top post). As with all measurements where yearly data points have large associated errors, longer term measures are more robust than short term measures. So it's possible that the calibration errors in ARGO floats haven't been completely eliminated and we aren't quite measuring the upper oceans reliably. It's also possible that some of the heat may be in regions of the oceans (greater depths) and partly escaped detection. it's also possible that for a short period there hasn't been a significant radiative imbalance (e.g. due to a particular coincidence of atmospheric effects), and so some of the heat wasn't missing at all (we'll get it as an "added chunk" as atmospheric fluctuations shift in the other direction). We have reasonable evidence that sea level rise slowed for a couple of years around 2006-2008, but that the longer term trend of sea level rise has pretty much caught up. The sea level rise in recent years can't be fully accounted for from knowledge of land ice melt, and efforts to "close the sea level budget" for these short periods require some thermal expansion (enhanced ocean heat) contribution [**]. So there are some interesting uncertainties to be resolved for this very short period of time. No doubt in the next few years these uncertainties will be resolved. However as with all areas of science, one doesn't choose one area of uncertainty, select a particular set of data, and then assume that encasing this within a bit of arithmetic defines absolutely what's happening in the natural world. ------------------------------- [*] In case anyone wants to check my sums: surface area of oceans: 3.61 x 10^14 m^2 volume of top 700 metres: 3.61 x 10^14 x 700 = 2.57 x 10^17 m^3 = 2.57 x 10^20 litres weight of this seawater: 2.57 x 10^20 x 1.03 kg (density correction) it requires 4186 joules to warm 1 kg of water by 1 oC raising the temperature of the top 700 metres of the oceans by 0.01 oC requires 2.56 x 10^20 x 4186 x 0.01 = 1.07 x 10^22 joules..... [**] recently reviewed here: A. Cazenave and W. Llovel (2009)Contemporary Sea Level Rise Annual Review of Marine Science 2, 145-173
118704. Doug Bostrom at 02:32 AM on 27 May 2010
        Robust warming of the global upper ocean
        Ken Lambert: The mechanism of heat transfer to the oceans from the atmosphere has always been unconvincing. You'll need to develop that assertion into an explanation better than what others practicing in the field have done before you're convincing. You do realize that, right?
118705. Doug Bostrom at 02:24 AM on 27 May 2010
        Greenland rising faster as ice loss accelerates
        Wes, read this to get up to reasonable speed on the whole subject: Spencer Weart's The Discovery of Global Warming. In particular your remarks about technological advances superseding the amount of C02 we've added to the air suggest a lack of sufficient background in the topic.
118706. Doug Bostrom at 02:17 AM on 27 May 2010
        Sea level rise is exaggerated
        Daniel you'd need to do some ferreting on your own to develop confidence in the idea but the time disparity in response you note is likely down to the fact that sea level rise is due not only to addition of water from melting ice but also significantly to thermal expansion of the sea itself. The world ocean has been quite efficiently absorbing "excess" retained heat and thus expanding in a noticeable way during the entire period in question while up here in the air the temperature has only more recently risen sufficiently to begin carving into terrestrial ice in a significant way, this in part because the ocean is indeed such a capacious sponge for warmth. There's a helpful primer on thermally-induced sea level rise here. There is an up-to-date and truly excellent discussion of sea level rise here* with a cornucopia of background information including some treatment of the lag of ice response versus ocean expansion. *Global sea level linked to global temperature Martin Vermeera, Stefan Rahmstorf 2009
118707. Phila at 02:11 AM on 27 May 2010
        Greenland rising faster as ice loss accelerates
        "Maybe they print this "alarmist" data because that is what all the data look like." Seems logical to me. And I'd take skeptics a bit more seriously if they'd give up their use of the term "alarmist." Either you have a valid scientific objection to the data, or you don't. If you don't, accusations of "alarmism" are meaningless. If you do, they're unnecessary.
118708. Michael Le Page at 01:53 AM on 27 May 2010
        Working out climate sensitivity from satellite measurements
        I think the page you link to on climate sensitivity could do with a little revising. It may be worth pointing out a) that most recent estimates of sensitivity based on past climate suggest it is rather more than the model consensus of around 3 C (eg Pagani 2009) b) that the reason for this is that models include only fast feedbacks ie Charney sensitivity
118709. PaulK at 01:50 AM on 27 May 2010
        There's no empirical evidence
        Riccardo, Well, erm, OK. I guess if my bank manager were to say he were going to repay only the interest instead of capital and interest, you could describe that as structurally identical. I think what you are saying is that you wrote "OLR" when you intended to write "Delta OLR", where you would/could define the latter as OLR(t)minus the radiative input or output prior to the forcing being imposed. I think you are also suggesting that in context, I should have been smart enough to figure out what you meant rather than what you wrote. In this, I think you are right. I should have spotted what you intended to say. However, by a remarkable non-coincidental coincidence, the expression you wrote for OLR actually corresponds to the radiative imbalance perturbation function for the boundary condition of constant TSI - the thing I was focused on in the first instance, and which I would like to return to. This really did throw me off. Given that we do now (I believe) have a common understanding of Schwartz, what I would like to do is to take the general solution I offered in #55 and demonstrate that (a)it works perfectly when applied to Schwartz if one accepts the same (restrictive) assumptions as Schwartz and (b) that it is a lot more versatile in its ability to accept realworld data in order to assess how OLR should be moving. Unfortunately, I don't have time immediately, but I will post on (a) as soon as I do.
118710. Chris G at 01:38 AM on 27 May 2010
        Working out climate sensitivity from satellite measurements
        Hmm. IDK, but it seems to me that a satellite history would be useful for observing radiative imbalance, which would be largely influenced by fast acting heat sinks, and to a lesser extent fast acting feedbacks. But how would you separate the two? Also, for instance, it takes a relatively short time to reduce floating ice and observe an albedo effect, but it could take centuries to see the albedo effects of ice sheet reductions. I don't know that it would be easy to ferret out the effects of feedbacks that could take centuries from the larger signals, especially when your record is short. I suspect the short record that is available is dominated by the heat sink signal of ocean heat content rising, plus, an arctic albedo change would be confused with an ocean heat content sink. Locations and timings aside, I can't see that the premise of Lindzen's work, that you can predict feedback effects from radiative imbalances, is sound.
118711. daniel at 01:35 AM on 27 May 2010
        Sea level rise is exaggerated
        I feel I am getting mixed messages from the AGW community. On one hand Sea level has been rising since the 1800's which is caused by anthropogenic emissions warming the planet. On the other hand melting rates for Arctic sea Ice and increases in the global mean temperature anomaly have only risen from "normal" or "naturally caused" levels since the mid 70's. Please clarify when exactly AGW was supposed to have had an effect or why these factors should be so vastly seperated in time.
118712. chris at 01:33 AM on 27 May 2010
        Greenland rising faster as ice loss accelerates
        HumanityRules at 12:18 PM on 26 May, 2010 HumanityRules at 12:45 PM on 26 May, 2010 There’s nothing particularly alarmist in the data on Greenland ice melt, but there’s no question that the prognosis is alarming. Obviously during the past 100’s and 1000’s of years sea levels have waxed and waned a little as long term temperature variations cause polar ice sheets to advance and retreat. However over the last 2000 years (where we have a reasonable handle on sea levels; [*]), the evidence indicates little net change in sea levels. So sea levels likely did rise above present levels (by of the order of 8-17 cm according to [**]) during the Medieval period, and were likely at a minimum (of perhaps 24-30 cm below current levels [**]) during the LIA. During Roman times sea levels were apparently similar to mid 20th century levels. Now it’s going to be all in one direction during the coming century (barring astonishing solar phenomena or massive volcanic activity, or a truly remarkable change in technologies for energy production or CO2 sequestration). It’s pretty well understood that the rate of sea level rise is roughly proportional to the temperature difference between some temperature at which polar ice variation is balanced, and the extant temperature [***]. So as the Earth temperature rises during the coming century the rate of sea level rise will very likely continue to increase. That’s the expectation of greatest likelihood. I would say that's pretty concerning… …but I don’t see how a straightforward consideration of the evidence is alarmist. [*] G. A. Milne et al. (2009) Identifying the causes of sea-level change Nature Geoscience 2, 471 - 478 abstract [**] A. Grinsted et al (2010) Reconstructing sea level from paleo and projected temperatures 200 to 2100 AD Clim. Dynam. 34, 461–472. abstract [***] S. Rahmstorf (2007) A Semi-Empirical Approach to Projecting Future Sea-Level Rise Science 315, 368 – 370 abstract [***] M. Vermeer and S. Rahmstorf (2009) Global sea level linked to global temperature PNAS 106, 21527-21532 abstract
118713. daniel at 01:18 AM on 27 May 2010
        It's a 1500 year cycle
        Can we trust that the ice core data is collected and interpereted correctly? Counting those fine lines using a variety of techniques and extrapolating climate way back into the past may sound straightforward to the average laymen but how much error is there in the graph? All it takes is a slight shift in the assigned timeline for one of the ice cores and viola the bipolar climate becomes global. Thanks for the video but you will need to present the graph with links to the source and a brief explanation of the methods and reliability of this data. :)
118714. wes george at 01:05 AM on 27 May 2010
        Greenland rising faster as ice loss accelerates
        You guys realize that it is hard to get to excited about Greenland's icecap melting at 300gt annually out of 2.8 million gt, especially since that's got to be the high end of the estimate. GRACE estimates the melt at only 185gt annually. It took 33 years to go from 0 to 300gt, at that rate accelerating technological evolution will have yield innovations both social and economically beyond our wildest dreams long before even 1.0% of Greenland's ice is lost. Hard to imagine our hydrocarbon-based economy surviving the next 40 years of technological evolution. If this is the signal of AGW, then just what part of it is catastrophic and unprecedented? "This is a big change, and it is a big deal." Why? Just what does 30 years warming trend really mean to the life cycle of 3 million gt icecap left over from the last ice age?
118715. Alexandre at 00:58 AM on 27 May 2010
        Working out climate sensitivity from satellite measurements
        I understood Lindzen's paper is about figuring out the relationship between radiative forcing and temperature. How was CO2 included there? How was sensitivity to CO2 calculated from periods of just a couple of years? Doesn't the Charney sensitivity have a multi-decade lag?
        Response: Climate sensitivity is about the climate's response to any energy imbalance. The definition refering to doubled CO2 is convention but it could just as easily say "climate sensitivity is the global temperature change caused by an energy imbalance of 3.7W/m2". So the key element of climate sensitivity is not how it responds to increased CO2 but how climate responds to warming. Eg - what feedbacks occur when temperature changes. This is the focus of Lindzen's and the other studies described above.
118716. ProfMandia at 00:54 AM on 27 May 2010
        Working out climate sensitivity from satellite measurements
        John, This is a very well done presentation and because it is short, to the point, and loaded with facts, it should be very effective. It appears that as more research gets published, climate sensitivity appears to converge on 3C with 2C being a very constrained lower bound. And, of course, 3C is not going to be pleasant at all (HUGE understatement). Scott A. Mandia, Professor of Physical Sciences Selden, NY Global Warming: Man or Myth? My Global Warming Blog Twitter: AGW_Prof "Global Warming Fact of the Day" Facebook Group
118717. Eric (skeptic) at 00:39 AM on 27 May 2010
        Satellites show no warming in the troposphere
        Re #15 suckfish, what matters is the distribution of the tropospheric warming. If it is concentrated then there will be more radiated heat and less retained. If it is diffuse then less radiated and more retained. The average increase or decrease doesn't tell us that and is not as important.
118718. Riccardo at 00:18 AM on 27 May 2010
        Has the greenhouse effect been falsified?
        Berényi Péter, could you please tell to which of the many figures posted in you comments you're referring to? Also, could you elaborate on the concept of the radiation temperature at the CO2 wavelength being "as cold as it can get"?
118719. Ken Lambert at 23:46 PM on 26 May 2010
        Robust warming of the global upper ocean
        HR #57 #58, kdkd #59 If Josh Willis' 0.1W/sq.m sequestered in the deep oceans (below 1000m) is correct, and the upper levels (down to 900m)are showing flat OHC from Argo post 2004, then Dr Trenberth's 0.9W/sq.m TOA imbalance is *nine* times the increase in OHC. Both cannot be right when there is no other feasible heat storage than the oceans. The 0.1 W/sq.m is small enough to be from other sources like undersea volcanoes or geothermal (warm bottom) sources. The mechanism of heat transfer to the oceans from the atmosphere has always been unconvincing. Try heating your bath with a radiant heater held above the surface or from warm air in a room. SW penetrates about 300m into water and LW a few millimeters. An immersion heater is a different story. Undersea volcanoes or geothermal heating would be much more efficient in heat transfer terms. Or the other 8/9ths of Dr Trenberth's heat could simply be lost to space where the heat sink is at -273 degC. The above 60 posts show that warming of the upper oceans is not 'Robust' at all. BP has got it pretty right in his application of the first law, and the conclusion that the large OHC increases prior to 2004 are offset errors in the XBT-Argo transition is much more 'Robust' I would suggest.
118720. Berényi Péter at 23:06 PM on 26 May 2010
        Has the greenhouse effect been falsified?
        Sylas, it is easy to see that radiation temperature in CO₂ stopband (between 14 and 16 μm) is about as cold as it can get. It means that photosphere (the region from where photons have a reasonable chance to escape to space) in this frequency band is above the troposphere. Below that line atmosphere is opaque (optically thick) in stopband. Now. In that region (lower stratosphere) temperature does not decrease with height anymore. If you put more carbon dioxide into air, photosphere will ascend, but its temperature may even increase slightly. Therefore OLR (Outgoing Longwave Radiation) should not diminish in this range with increasing CO₂. If you want to explain "greenhouse effect" anomaly due to changing carbon dioxide levels, you should provide some more details. Thanks.
118721. michael sweet at 22:48 PM on 26 May 2010
        Greenland rising faster as ice loss accelerates
        Humanity rules: Can you provide evidence that Nature and Science are alarmist beyond your desire for them to be incorrect? These are two of the top journals in science today. They are well known for their unbiased publishing of a very wide variety of material. Why should they be biased in this one subject? Maybe they print this "alarmist" data because that is what all the data look like. If we have no evidence that they are biased the default hypothesis is that the data is really this bad. Sceptics are welcome to submit papers to Science if they have good data.
118722. kdkd at 22:28 PM on 26 May 2010
        Robust warming of the global upper ocean
        HumanityRules #57 There's certainly something wrong somewhere. Your final comments are a mis-statement of the scientific process. If someone can find strong evidence that the missing heat doesn't actually exist then that will make their career. Meanwhile the surface observations are what are used to make the (to date rather conservative) IPCC & co predictions, and the heat imbalance model is a bit of a side show to the main game. Much as some people would like it to be central. However the uncertainties relative to the other things that are measured better, and easier to measure are so high this won't happen for a while. What's the uncertainty on the 0.1 W/m2 term by the way, i.e. ± how much?
118723. HumanityRules at 21:40 PM on 26 May 2010
        Robust warming of the global upper ocean
        From the Pielke Snr website this was Josh Willis assessment of Johnson most recent paper on deep ocean warming "They looked at the prospect of deep warming on decadal time scales using the sparse, but highly accurate repeat hydrographic sections and found that below 3000 m in the global oceans, and below 1000 m in the southern ocean, the ocean is taking up an energy equivalent of about a 0.1 W/m^2 energy imbalance at the top of the atmosphere. So while this is significant, it suggests to me at least that the deep ocean is probably not taking up a bunch of heat really rapidly and the traditional idea that most of the action is in the upper several hundred meters is probably going to hold up."
118724. HumanityRules at 21:38 PM on 26 May 2010
        Robust warming of the global upper ocean
        54.kdkd "it seems extremely likely that large scale observations of warming are also due to the same CO2 parameter." I guess it's the 10 of the 16years of OHC showing no large scale observations of warming that makes me question this. It's the reduced uncertainty in the measurement system for the most recent period of no warming that further backs up my cautious approach. This isn't even necessarily a question of if AGW is occuring but could just be the magnitude. Everybody seems fixed on finding the missing heat rather than considering whether we should reduce our overall estimate of the build up of energy in the system based on these observations. Given the singularity of this approach there's likely only one possible outcome somebody, somehow will find the missing heat.
118725. Ned at 21:06 PM on 26 May 2010
        Collective Intelligence and climate change
        Putting aside Doug's car for a moment, I like the idea of this "Deliberatorium" experiment, but the implementation is not so great. It's an awkward and confusing user interface, there's a shortage of explanations and instructions, the text of the arguments is full of typos and grammatical errors, and if you want to be thorough about it, wading through the whole thing to rate all the arguments takes ... forever. If that's intended as a real research project, rather than just somebody's toy, they should pull the plug, invest much more time in the user interface, and then re-launch.
118726. Riccardo at 19:56 PM on 26 May 2010
        The significance of the CO2 lag
        batsvenson, if common sense doesn't help, if chris's numerical example above doesn't help either, try the math yourself or see here.
118727. Riccardo at 19:18 PM on 26 May 2010
        There's no empirical evidence
        PaulK, "Clearly, the structural forms are very different." They are not. Indeed they're identical apart from the term Q(0) which comes from working with T instead of ΔT and the use of C/λ which is τ. It's just simple math. @Doug sorry to disappoint you. It was not much fun, just trivial math. :)
118728. kdkd at 18:59 PM on 26 May 2010
        Robust warming of the global upper ocean
        Riccardo #55 Absolutely. The measurement model as it stands is indadequate to assess these heat budgets with a reasonable degree of certainty over a sufficiently long timescale. Until we have enough good quality data over a long enough timescale, this global heat balance stuff will not be good enough to make a substantial contribution to the state of the scientific consensus.
118729. batsvensson at 18:50 PM on 26 May 2010
        The significance of the CO2 lag
        @chris, Ned, et al. RSVP claim is that "A causes more of B cause more of A is a runaway solution". This claim is valid. The straw man attack on RSVP claim is to claim RSVP stated "A causes B cause A", which he never did.
118730. Riccardo at 18:48 PM on 26 May 2010
        Robust warming of the global upper ocean
        I know I'm going to be a bit boring by repeating the same thing, but I cannot resist to quote from the paper linked by Doug (thanks Doug, by the way): "The data from these repeat sections suggest that abyssal variations may contribute significantly to global heat, and hence sea level, budgets. To close ocean heat, sea level, and likely freshwater budgets on interannual time scales, the ocean below 2000 m must be much better sampled in space and time than it has been, or is likely to be, relying on repeat hydrography alone." Different paper, different people, similar conclusions, it's a travesty we cannot track the flow of energy through the climate system.
118731. batsvensson at 18:39 PM on 26 May 2010
        The significance of the CO2 lag
        @Ogemaniac at 10:47 AM on 19 May, 2010 "few seem to understand that not all positive feedbacks are "runaway". " True if the control system use a discrete time sampling model. (Which climate models do but, as far as we know, mother nature doesnt.)
118732. johnd at 17:54 PM on 26 May 2010
        Collective Intelligence and climate change
        doug_bostrom at 10:36 AM, you think you have problems with your fuel gauge. My car has a readout that tells me how much further I can travel on the remaining fuel. Trouble is that distance really does decrease faster than the distance on the odometer increases. If ever two pieces of data should correlate, these are those two. The manufacturer solves the problem by the remaining distance readout going blank once it goes below 50 km. I'm wondering if there is some other form of data that I could input, such as tyre pressures as they should increase due to heat buildup the further the vehicle travels, but I don't know whether it can be correctly calibrated given I drive on both gravel and paved roads, or if it's even relevant. :-(
118733. HumanityRules at 17:12 PM on 26 May 2010
        Collective Intelligence and climate change
        4.doug_bostrom ditto your gas gauge. You thought about selling that pile of junk? ;)
118734. HumanityRules at 17:02 PM on 26 May 2010
        Collective Intelligence and climate change
        3.doug_bostrom I got no problem with you driving your car based on your dodgy pressure measurements. It when you demand the complete re-organisation of the transport system based on them that I think it's necessary to take a closer look at your notebook.
118735. kdkd at 16:59 PM on 26 May 2010
        Robust warming of the global upper ocean
        HumanityRules #52 Given that we can't model the observed 20th and 21st century warming without using CO2 as a parameter, it seems extremely likely that large scale observations of warming are also due to the same CO2 parameter. This is not mathematics, we can't provide logical proof - inductive proof is just how science works, and the global warming story is remarkably consistent for such a large poorly measured complex system. Just because some things are uncertain in the measurement system, it doesn't follow that everything is uncertain, which appears to me to be your argument. More generally I'm most unimpressed with the way that short term problems with the measurement model of ocean heat content are used by so called climate sceptics to try to draw strong conclusions about longer term climate implications, discarding much prior work on the topic in the process.
118736. Doug Bostrom at 16:38 PM on 26 May 2010
        Robust warming of the global upper ocean
        HR, no problem and I realized I sounded defensive as soon as I hit the "Submit" button. I'm trying to retrain myself to avoid signaling unfounded conclusions so was trying to be clear on that. OT but speaking of "Submit", I wonder what is the subconscious effect of that common term used on web interfaces, at sites sometimes featuring contention? Reminds me of the old New Yorker cartoon depicting a heavily ribboned and brassed military man at the wheel of his automobile, approaching a "Yield" sign and barking out "Never!"
118737. HumanityRules at 16:13 PM on 26 May 2010
        Robust warming of the global upper ocean
        51.doug_bostrom I wasn't accusing you of assigning casuality more this publication and the general assumption this is a AGW signal. It maybe but there seems a lot more to measure and explain before we say it is.
118738. Doug Bostrom at 15:58 PM on 26 May 2010
        There's no empirical evidence
        Holy Cow, this is fun to watch.
118739. Doug Bostrom at 15:07 PM on 26 May 2010
        Robust warming of the global upper ocean
        HR, I'm not assigning any causality or even forming conclusions, instead looking at what's available in the way of hints in publications such as those I cited. Recent Bottom Water Warming in the Pacific Ocean (pdf, full text) has a pretty good discussion of general factors controlling transfer of heat in the ocean, definitely worth a careful read. Be sure not to become beguiled or transfixed by the sentence "Abyssal cooling of about 0.02°C has been reported in the southwest Pacific Ocean...", heh! Ok, I lie, I'll allow myself one conclusion, namely that the classical understanding of vertical heat transfer in the ocean is appropriately conservative in the face of limited understanding of what's actually "going on down there" but needs and indeed is receiving some freshening (pun!). It'll be absolutely fabulous to see some instruments drifting around in the bottom half. Can we hold our breaths that long? I doubt it!
118740. HumanityRules at 14:03 PM on 26 May 2010
        Robust warming of the global upper ocean
        48.doug_bostrom "Seeing that the upper ocean is not effectively isolated from the lower approximately 1/2 of the ocean" I had it in my head that the deep and upper ocean are effectively isolated in our classical understanding. The known mechanisms tranfer relatively small amounts of energy to the deep on a year to year basis. Look at the difference in heat accumulation in 2003 and 2004. Given that the ocean is just sitting there absorbing the suns energy then those large differences need to be accounted for before you can start asigning causality.
118741. Pat Moffitt at 14:01 PM on 26 May 2010
        Unprecedented Warming in Lake Tanganyika and its impact on humanity
        johnd at 08:53 AM on 26 May, 2010--If we are looking at the total amount of nutrients within the entire lake water column- then harvest will have a minimal effect on the total nutrient store. (The residence times are enormous). Internal recycling is critical to this lake however the production of biomass is complex and terrestrial sources do have a role. I don't really see the loss of nutrients to the fish catch as a vital link here. Overfishing may have deleterious and multiple effects that can cascade through the system but I don't think it is related to the loss of nutrients within the harvested fish. Langenberg's thesis posits that the changes in fish production catch data are the result of fishing practices not climate. In fact he showed that increasing temperatures that lead to a shallower mixed layer does not necessarily result in decreased production. However the ability to blame climate may perversely lead to a collapse in the fishery by undermining the need of he involved parties to create and enforce a workable fishery management plan.
118742. HumanityRules at 13:56 PM on 26 May 2010
        Robust warming of the global upper ocean
        47.CoalGeologist i'm not so concerned about the accuracy of the data. It's the best we've got and have to accept that. What I'm concerned about is taking highly variable data, drawing a straight line through it and saying look it's AGW. This is not an objective process like writing down readings from an instrument. For every argument that says this is a valid approach there is one which will question the validity.
118743. actually thoughtful at 13:45 PM on 26 May 2010
        Collective Intelligence and climate change
        The deliberatorium needs an expand all. And more sophisticated arguments, with sources. It kind of, sort of, needs to be more like skeptical science!
118744. HumanityRules at 12:45 PM on 26 May 2010
        Greenland rising faster as ice loss accelerates
        47.Jeff Freymueller Your post sort of contradicts the general idea that the earth as a whole has been losing ice for 200-300years (with some reversal periods). Hopefully your not suggesting that ice loss is only a 21st century phenomenon. Here's a longer term estimate of Greenland mass balance. (It came from here which looks to be an endless sourse of climate change imagery. Try Greenland in teh search for example)
118745. jimmck at 12:30 PM on 26 May 2010
        Human CO2 is a tiny % of CO2 emissions
        I am please to find this site as I have been working on building up a Balance Sheet and "C" Flow for the period 2000 to 2010 and you have filled in some gaps. It seems to me that ocean temperatures must be rising. If they were static then the oceans would absorb any amount of CO2 due to equalisation of partial pressures given thay there is 50 times as much CO2 in the oceans as in the air. How much has the average ocean temperature changed from 2000 to 2010.
118746. PaulK at 12:28 PM on 26 May 2010
        There's no empirical evidence
        Riccardo, The solution I proposed for OLR in posts #52 and #55 is mathematically exact, and makes very few assumptions. The solution is based directly on a flux response function which varies as a function of time, and therefore represents a generalized solution to a wide variety of energy balance models. Because it makes very few assumptions, the conclusions about the shape of the OLR response are mathematically robust but have low information content. I would prefer to use this model directly as a basis to discuss observed OLR response, rather than a more informative model, but with questionable assumptions. However, in response to the points I made about the geometry of the OLR response, you referred me to the Schwartz paper and you attempted to abstract a solution for OLR from that model (your posts #56 and #60). I did the same thing, initially mistakenly assuming that F was a net forcing in time (Q(t) – E(t)), since Schwartz rather loosely describes F as a Delta(Q-E). When I reexamined the solution form, however, it was apparent that F has to be an impulse forcing in Schwartz, as more conventionally applied. So I again recalculated OLR and found that I had a solution that was different from (both your original and) your corrected OLR solution. I concluded, since we had been talking originally about net flux response functions, that you were misunderstanding the F term in Schwartz. It is apparent from your last post that this is not the case. Therefore, I now believe that it is either your maths or mine which are wanting. For the case F=bt, I obtain the following result for OLR, using the Schwartz model and Schwartz nomenclature:- C * d(Deltat)/dt = CdT/dt = dH/dt =Q(t) – E(t) = net flux in time For constant input Q(t) = Q(0) for all t. We “transfer” the forcing to the output side as follows: Net flux in time = Q(0) –(E(t)-F(t)) = Q(0) – OLR(t) = C*d(Deltat)/dt Hence OLR(t) = Q(0) - C* d(Deltat)/dt But Deltat = b((t-tau) + tau*exp(-t/tau))/lamda and Therefore d(deltat/dt) = b(1-exp(-t/tau))/lamda Substituting into the solution for OLR we obtain : OLR(t) = Q(0) – Cb(1-exp(-t/tau))/lamda Note that at time t=0, we obtain OLR(0) = Q(0), and for t>>tau, OLR tends to a constant = Q(0)-Cb/lamda = Q(0) –b*tau. If we note that b can be written as F(tau)/tau, then this asymptote is equal to Q(0) – F(tau). All of this seems reasonable to me within the context of the assumptions made. The above solution may be compared with your corrected solution (post#60) : OLR(t) = β *((t-τ)+τ*exp(-t/τ))-β*t Clearly, the structural forms are very different. I emphasise that I am not wedded to the Schwartz model, but I believe that we need to get this out of the way if there is any hope of having a sensible conversation on the subject of whether an observed rise in OLR can be rendered compatible with common assumptions.
118747. HumanityRules at 12:18 PM on 26 May 2010
        Greenland rising faster as ice loss accelerates
        46.Jeff Freymueller That's the problem I did biology and chemistry at High school. 43.llewelly Thanks I think I've got that it's to do with vectors etc. still not sure that in Riccardo's example the outside force of gravity is not having an effect to change the rate of acceleration but let's move on. If this study shows that for almost half the time of the study period Greenland and Iceland were accumulating mass rather than losing it I'm still concerned with teh emphasis on ice loss here. There is variability in ice accumulation so what. It seems like Nature and Science are competing to produce reports that can generate the most alarmist press releases, news reports or politicians oneliners. Irrespective of what the full data set tells us. This is worrying.
118748. Eric (skeptic) at 12:09 PM on 26 May 2010
        Polar bear numbers are increasing
        Riccardo, the Norwegian group doesn't use the word hunting, only the word "removal" which is an obfuscation. The Baffin Bay population with 2000 bears has a hunting quota of about 100, but in fact about 200 have been hunted each year. But the indigenous groups maintain that the population is both underestimated and replenished by polar bears migrating from neighboring areas.
118749. Jeff Freymueller at 12:09 PM on 26 May 2010
        Greenland rising faster as ice loss accelerates
        #36 fydijkstra, the key point you seem to be leaving out is that Greenland was not losing much mass (maybe not any) in the late 20th Century, and then over a short period of time it switched over to shedding mass like crazy. The changes in uplift rate observed here are far bigger than the uplift or subsidence rates observed over most of the planet. This is a big change, and it is a big deal.
118750. Jeff Freymueller at 12:04 PM on 26 May 2010
        Greenland rising faster as ice loss accelerates
        #44 johnd, HumanityRules was mixing up velocity and acceleration, and getting very confused. The ball in the air example is a basic high school physics problem, so it seemed a logical one to me. Especially given that the acceleration is due to gravity, and we all (should) know that gravity is always pulling objects back to the ground. I like your block of ice on a kitchen scale analogy quite a bit. Especially if you think about the sort of kitchen scale that visibly depresses when you put a weight on it. As the block of ice melts and the water drips away, the weight reading on the scale will get smaller, and the scale will rise up as the ice melts. What's missing from the scale analogy is that this movement is superimposed on a general subsidence or uplift, so what you see most clearly is a change in the trend of height over time.

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