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HumanityRules at 23:43 PM on 20 April 2010Tracking the energy from global warming
You can access were Trenberth gets TOA data for figure 1 at BAMS State of the Climate 2008. Go to page S33. Read to the end because it discusses some of the issues with the dataset. It seems the quality of the data has reduced over time in this series with the early data seeming to have better stability than later material. Trenberths smoothed black line must be based on Figure 2.26 but I don't immediately see the connection. I also hunted down this presentation by the same guys. Page 20 shows Figure 2.26 while page 21 shows an updated version. -
Glenn Tamblyn at 22:57 PM on 20 April 2010Where is global warming going?
And with that 2.3% sitting next to that great big 93.4%, the 2.3% can easily get pretty volatile. And Juliet Davenport. You are so right. Looking at AGW as energy change should be a no-brainer. But that assumes that people have a technical education so that looking at the world in terms of energy and quantification is second nature. My humble BEng(Mech) leads me to do that as a matter of course. But how many of our friends, family, neighbours, fellow countrymen look at the world that way. How many naturally seek to quantify a problem as their first step to understanding it? This is the terrible insidious danger of AGW. The appropriate way of looking at it, the best mode of thought on the subject, is simply a foreign language and mental framework for the majority of people. So people distrust their lack of understanding of it more than they fear the actual problem. A foreign idea gets doubted precisely for its foreignness, not for its correctness. -
HumanityRules at 20:33 PM on 20 April 2010Where is global warming going?
Nice graphic, although I'd like to see the others in orbit around the large 'sun-like' ocean :) So why are we concerned about a tiny 2.3%? A simple answer might be because that is were we've being doing most of our measurements for along time. Science has to be pragmatic.Response: "So why are we concerned about a tiny 2.3%?"
I thought the answer to that was obvious... we live in that 2.3% -
Juliet Davenport at 20:30 PM on 20 April 2010Where is global warming going?
I wonder about how to communicate this further than just the concept of "heat" - because in countries where it tends to be cold, "heat" has a positive connotation - and vice versa in warm countries. Could we explain what the warming affect actually means within each of the environments? The phrase Global Warming is more widely associated with temperature and perceived by how we feel it, but does not explain what "work" is done as a result of global warming, and what impact that has on systems. To make it straightforward what does heating the oceans actually mean? What does heating the atmosphere really mean, and are we talking about in terms of ice-sheets - is that "work" related to the amount of heat given to the ice-sheet but with no temperature change? Sorry for the stream of consciousness! -
Peter H at 18:46 PM on 20 April 2010Where is global warming going?
Seems to me this might provoke a 'so why are we concerned about a tiny 2.3%' comments. And isn't it not about the amount of energy but, given the atmosphere is so much less mass than the oceans, the relative effect of that 2.3% on a much smaller mass. So, I'd like to see a mass v change graphic for each component I think -
Ed Davies at 18:30 PM on 20 April 2010Where is global warming going?
"The ocean heat figure of 93.4% is almost certainly an underestimate as it only includes ocean heat down to 700 metres (Levitus 2005)." I think I'm with John Russell on this one. As I understand it, a lot of the "natural variation" in the climate, that part usually described by the shorthand "El Niño", is the result of changes in the rate of transfer of heat from the top levels of the oceans to deeper levels so when the globe is supposedly cooling what's really happening is the heating is happening deep in the ocean rather than on the surface. Therefore, what's of interest is the rate of change of total heat content of the ocean all the way down, not just the surface or even the top 700 metres. Are there now enough measuring buoys, etc, to plot that reliably? -
Berényi Péter at 18:17 PM on 20 April 2010Where is global warming going?
There is another heat reservoir around for Global Warming to go. It is actually the coldest of all (-270 °C). The huge March temperature anomaly around the North Pole for example, while temperatures are higher than average, is still pretty cold (way below freezing). This excess heat can not go to the oceans, because open sea surface is defined to be above freezing temperature and according to the Second Law heat is never transferred to a warmer reservoir from a colder one. It has simply nowhere else to go but space. -
John Russell at 17:58 PM on 20 April 2010Where is global warming going?
Is not averaging effect created by the colossal thermal mass of the oceans the reason why the evidence of rising ocean temperatures -- as opposed to the much more erratic atmospheric temperature readings -- is so much more useful when attempting to convince sceptics that there is a clearly visible overall warming trend? -
Berényi Péter at 17:44 PM on 20 April 2010Tracking the energy from global warming
#49 Moderator's comment to Marcel Bökstedt at 05:31 AM on 20 April, 2010 what we're finding is the satellites are measuring an increase in the energy imbalance Are we? I am avare of an online analysis up to 2005:
It does show that the alleged huge 2003 step-like increase in OHC is probably an artefact due to changing instrumentation (mass deployment of ARGO floats).
However, I could not find s similar analysis for the last five years. I agree with you on satellite net TOA radiation imbalance measurement's precision being better than its accuracy, especially since CERES started.
Unfortunately the NASA Radiation Budget Data Products page is a mess. Can anyone find recent data preprocessed enough to be shown here?
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Jeff Freymueller at 11:32 AM on 20 April 2010Tracking the energy from global warming
#32 frogstar, it looks like one of your questions was never answered. There are many examples of quantities where we can measure Q(t2) - Q(t1) much more accurately than either Q(t2) or Q(t1). All it takes is for there to be some poorly known factor that contributes to both of the absolute levels Q(t1) and Q(t2), but cancels out when you take the time difference. This is actually a very common situation in all areas of science. -
HumanityRules at 10:29 AM on 20 April 2010Tracking the energy from global warming
It's worth reading about the confidence the IPCC had in the ocean data back in 2007 when the present divergence wasn't obvious. Fig 5.1 is enlightening in that the confidence intervals narrow over time representing an improvement in the data. Trenberth's analysis would have it that those confidence limits have widened again even though we have greater data coverage. I guess figure 5.4 also emphasises why the ocean heat content is so important to this issue. I'd be interested in seeing an undated Figure 5.4 covering 2003 to 2008. (You could read from this page onwards) http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch5s5-2-2.htmlResponse: Here's Figure 5.1 that you refer to:
Note that this refers to ocean heat from 0 to 700 metres deep. The issue here is the ocean heat measurements at deeper levels - both down to 2000 metres for which there is ARGO data and deeper, for which the data is more sparse. Figure 5.4 is even more interesting (in fact, has inspired an idea for a nifty graphic and a blog post), so here it is:
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HumanityRules at 09:49 AM on 20 April 2010Tracking the energy from global warming
43.dhogaza I’m not sure you quite represent the position of each of the scientists accurately in the Pielke/Trenberth/Willis discussion. Trenberth notes that estimates of energy content of the ocean in the literature based on Argo data has a quite wide spread. Willis points out that early results contained errors, since these errors where identified estimates are all now in agreement. Willis thinks coverage is now good and the likelihood that further large errors are unlikely, like a good scientist he doesn’t completely rule out further adjustments. Ultimately Willis seems to think the Argo data is robust while Trenberth thinks it still contains large error. The degree to which both scientists think the Argo data contains errors is very important here. Given Willis is the expert on Argo data it does appear Trenberth is having his own Dunning-Kruger moment. But further experience will undoubtedly resolve this. 49.Marcel Bökstedt I agree we haven’t focused enough on the TOA estimates, thanks John for the reply. Do you have the references for any of this work? -
michael sweet at 09:39 AM on 20 April 2010Flowers blooming earlier now than any time in last 250 years
Johnd A number of scientific papers have been cited that show that spring is advancing. These papers measure the response of farmed plants and natural plants and also the behaviour of animals. You can check the data and find out how much is based on natural plants and how much is based on farmed plants. I have read some of these studies (there are hundreds of published papers) and am satisfied that the issue is caused by increasing temperature. You need to cite data that suggests that is not the case. As far as changing the standard of what is measured, I am sure that the farmers in Australia measure and track soil moisture every year at many locations. Find a summary of that data. See how it compares to this data of plant responses. Just because you have not looked for it does not mean that the data does not exist. If spring comes earlier it may become too hot in summer for plants to grow, because there was not enough time for the soil to accumulate water in the winter. Of course if you live in Sibera you might welcome the warmth. The point for this thread is that the weather is measurably changing. This is caused by human intervention in the climate system. This is additional proof of AGW. -
Jacob Bock Axelsen at 06:28 AM on 20 April 2010Are we too stupid?
embb The title says: economists warn about CO2 trade wars. Maybe they missed something? Der Spiegel certainly misses on the truth about climate scientists, but perhaps they are right in this case. At the other extreme, Lovelock and even the Pentagon predicts climate change related wars. A trade war seems the lesser evil. My post is about peer-reviewed realistic mechanisms that can avoid both the tax and the wars. "organised crime creates a fraud of billions with the trade of certificates" As that article correctly states, this large tax fraud has no effect on emissions. An analogue would be to conclude anything on the usefulness of dollar bills in light of the fact that 90% carry traces of cocaine. "(...) the US in this case (...) did not sign so they could not defect by definition." Surely most would agree that not signing at all is defecting to act on mitigating climate change. Who would sign and implement major emission cuts after that? "The question is how you can implement a tit for tat in the case of emission taxing." You did write "if you emit co2 I will emit co2", but no matter. You still incinuate a game between two prospective taxpayers. The pay-off demands for a dilemma are obviously: temptation > mutual cooperation > mutual defection > being cheated. For two agents the 'tax-payment-game' is trivial and looks something like this: i) Mutual defection and temptation is the initial saved tax payment, tax, plus the high probability of a fine, fine=tax, and N years in prison: pay-off = tax - fine - N*income << 0. Naturally, on top of this comes the future cost of indirect reciprocity from your surroundings that disapprove of parasitic freeloaders. However, you benefit from the public goods financed by the tax. ii) Mutual cooperation and being cheated is 0 plus the public goods financed by the tax. Your average payoff when cooperating is larger than 0, and your average payoff when defecting is much less than 0. No dilemma. If you disagree, then by all means, try to disprove it. Of course, the mafia may change the pay-off matrix. However, that is a choice between money versus lowered life expectancy, reduced fertility, stress and violence. A choice that most are able to turn down. Back to reality: A production company in China is part of society, so the authorities can document if they used power which lead to CO2 emissions. The company immidiately recieves the pay-off from not paying the tax, but faces much stronger punishment when caught, because the authorities do not wish to loose exports. China, inspite of being a communistic dictatorship, has already understood the pay-off from international trade and domestic entrepreneurship. It gets better. James Hansen has proposed that the tax revenue is divided among the payers. The dividend actually creates incentive to further and further decrease your emissions. This is guaranteed to work because it has been working in California for the last 35 years. BTW, the latest and most extreme reform was put in place by the famous 'armchair activist' Arnold Schwarzenegger. -
Leo G at 05:48 AM on 20 April 2010Tracking the energy from global warming
Marcel @ 49 - Thought you might like this reply to Dr. Trenberth from Dr. Willis, on Pielke Snr.'s blog http://pielkeclimatesci.wordpress.com/2010/04/19/further-feedback-from-kevin-trenberth-and-feedback-from-josh-willis-on-the-ucar-press-release/ "....You should also note that Karina’s paper suffered from errors in the altimeter data that were still not corrected at the time of her paper. These errors tended to make the altimeter time series show too much global sea level rise, and after correcting them the trend in globally averaged sea level since 2004 or 2005 is significanly lower. Finally, I do not think that any of the techniques used by various groups should be supressing the global warming signal in the data over the period from 2005 to the present. As I mentioned above, the Argo data coverage during this period is such that any reasonable interpolation technique should do. Capturing the trend over 50 years, however, is another story. Cheers, Josh" -
Marcel Bökstedt at 05:31 AM on 20 April 2010Tracking the energy from global warming
Berenyi Peter> I'm inclined to agree with you, this seems to be a point where the model does not agree with the data. The situation is unclear though, so its probably best to wait for better observations both from satelites and from the deep ocean. Humanity rules> I agree, whatever the answer is, it has to explain the observed rise in sea level, and this is also a restriction on the warming of the deep ocean. I'm not sure I understand the relevance of the satelite data as they exist today, Trenberth seems to claim that they do tell us something, but I'm not sure what. If someone has got this point, please explain!Response: The point with the satellite data is it's not able to determine the absolute energy imbalance with great accuracy. However, as Trenberth puts it, "satellite measurements are sufficiently stable from one year to the next, so that by measuring incoming solar radiation and outgoing infrared radiation, it is possible to track changes in the net radiation".
So satellite measurements are useful to determine whether the energy imbalance is rising or falling. And what we're finding is the satellites are measuring an increase in the energy imbalance while ocean heat measurements find a decrease in energy imbalance. As both these metrics are measuring essentially the same thing, this discrepancy needs resolving. -
garythompson at 04:27 AM on 20 April 2010Tracking the energy from global warming
#22 vocta - thanks for pointing me to the right paper! so i read that one and it appears that the 0.9W/m2 net TOA imbalance comes from models. the actual measurements were 6.4 W/m2 which is way "outside the realm of current estimates of global imbalances" as Trenberth states. the authors further go on to state that "the TOA energy imbalance can probably be most accurately determined from climate models...." so am i understanding this correctly? every time we rely solely on measured data we get a TOA imbalance that is impracticle so instead we use model results. Pardon my ignorance but this seems very troubling to me why the scientist can't reconcile this and bring models and measurements into agreement. to me, TOA imbalance seems like the perfect tool to use to validate and/or monitor AGW. The fact that there is so much uncertainty in this is troubling. as a somewhat unreltated question - it seems to me that most satellite measurements of OLR are over bodies of water/ice. do we have any over land? -
Peter Hogarth at 04:24 AM on 20 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
HumanityRules at 19:55 PM on 17 April, 2010 I wouldn't say there is really a contradiction. You may argue the "turning point" is different in the simulation (from Vinje 2003) compared with the actual observations, but it depends how we fit a curve or trend. If one curve went upwards, - now that would be a contradiction! I would suggest the curve "fit" I originally used is an indication, used to illustrate long term "increase" or "decrease" in slope. It is useful in this regard. I used the simulation image (perhaps lazily) to highlight what the experts (who also use the data Peter B nicely animated) believe sea ice extent was like during this period, when actual data is extremely sparse. I would expect the models/simulations to have improved somewhat since 2003. -
mike roddy at 02:58 AM on 20 April 2010Earth's five mass extinction events
Thanks for this, fascinating stuff, especially Chris #45. I have a question for nobody in particular: Hansen says that burning all the coal and tar sands will lead to Venus. BAU projections call for 5-7C temps in 2100, which is deadly, but not Venus. Does this mean that feedbacks at 5-7C will subsequenstly overwhelm the planet, since the rise in CO2 has been so rapid? -
Tom Dayton at 02:55 AM on 20 April 2010Flowers blooming earlier now than any time in last 250 years
JMurphy, I think this is close: We’re coming out of the Little Ice Age And a runner-up is It’s a climate regime shift -
Tom Dayton at 02:45 AM on 20 April 2010Tracking the energy from global warming
And, RSVP, the Earth's core continues to cool despite the contributions of radioactive decay. This topic is addressed by a Scientific American article, Why Is The Earth's Core So Hot?. -
GFW at 02:39 AM on 20 April 2010Tracking the energy from global warming
Chemware @12. Presumably everyone ignored this because it was wrong. Watts are already energy/time. 1W = 1J/s. So Wm-2 is an energy flux, and the area under any curve segment in figure one would represent energy (per square meter) accumulated during that time. -
GFW at 02:33 AM on 20 April 2010Tracking the energy from global warming
RSVP @34. Although the earth's core was initially so hot due to the energy of gravitational infall as the earth accreted, it is believed that the source of the majority of the heat keeping it so hot is simply radioactive decay. -
Doug Bostrom at 02:32 AM on 20 April 2010Tracking the energy from global warming
RSVP the Earth's heat derives from energy conserved during the accretion of material forming the globe as well as by isotope decay, principally potassium-40, uranium-235 & 238, thorium-232. -
JMurphy at 02:22 AM on 20 April 2010Flowers blooming earlier now than any time in last 250 years
Is there a thread dealing with the common refrain that 'temperatures are naturally rising because we are recovering from the last ice age' ? The closest I can find is one dealing with the postponement of the next glacial maximum (or ice age), because of all the CO2 in the atmosphere. -
dhogaza at 02:16 AM on 20 April 2010Tracking the energy from global warming
The discrepancy is not between net radiation balance at TOA as measured by CERES and OHC as measured by ARGO, but between OHC measurements and computational model predictions. In cases like this the standard pre-postnormal science procedure is to abandon model and stick to measurement.
Yeah, well, Christy and Spencer said the same thing when their early satellite temperature reconstructions showed cooling rather than warming. Turns out the models (and surface temp measurements) were right, and Christy and Spencer were simply error-prone (several times over) and had made a seriously flawed analysis. What's the relevance to OHC vs. TOA vs. models? Trenberth:We are well aware that there are well over a dozen estimates of ocean heat content and they are all different yet based on the same data. There are clearly problems in the analysis phase and I don’t believe any are correct. There is a nice analysis of ocean heat content down to 2000 m by von Schuckmann, K., F. Gaillard, and P.-Y. Le Traon 2009: Global hydrographic variability patterns during 2003–2008, /J. Geophys. Res.,/*114*, C09007, doi:10.1029/2008JC005237. but even those estimates are likely conservative. The deep ocean is not well monitored and nor is the Arctic below sea ice. That said, there is a paper in press (embargoed) that performs an error analysis of ocean heat content. Our article highlights the discrepancies that should be resolved with better data and analysis, and improved observations must play a key role.
Shorter form: current observational data and reconstructions of OHC built on said data pretty much suck at this point. This, BTW, is totally in line with his "travesty" e-mail touted by denialists as showing the Trenberth doesn't think there's been warming. Talk about misunderstanding the point ... Now, Josh Willis:I think that it is still premature to make claims about the Earth’s energy imbalance based on satellite observations and ocean heat content data over ANY period. As with the satellite observations, the ocean heat content data continue to undergo refinement and removal of systematic errors. Since the satellite data are insensitive to the absolute value of the imbalance, they rely on ocean heat content data to estimate it. However, I personally belive that there is not a long enough common period between the satellite observations and the RELIABLE ocean heat content record to make any strong claims about the energy budget. Many people are working on both data sets, however, and I hope that a more reliable comparison will become available soon.
You yourself said: "Well, net radiation balance at TOA (Top of Atmosphere) as measured by ERBE & CERES satellites is 2 ± 5 W m-2, that much we know. Unfortunately this outrageously inaccurate value is quite useless for checking OHC history reconstructions." Apparently you're unaware that there's something circular in the notion of using TOA satellite reconstructions to check OHC reconstructions (since Willis points out that the former depends on the latter ...)? Anyway, two experts in the field suggest that your faith in the observations is, at this point, misplaced, and that the quality of observational data available to date isn't good enough to warrant "throwing out the models". Just as the quality of Christy and Spencer's early satellite temperature reconstructions weren't of good enough quality to warrant "throwing out the models". -
Doug Bostrom at 02:10 AM on 20 April 2010Tracking the energy from global warming
Ken, I'm not sure why you'd need to get a instantly simultaneous reading from Argo buoys in order to derive a trend in total OHC from their collective data. If for instance you obtain a reading from each buoy over the course of 36 hours, wait for 6 months and then repeat the collection process, the 36 hour collection period should essentially vanishe from the OHC signal. There's a nice near-realtime map of Argo buoy distribution available: Current Argo distribution map -
Chris G at 02:02 AM on 20 April 2010Tracking the energy from global warming
The case for a change in circulation patterns might be getting stronger. Changes in salinity distributions are being found, and since it is a thermohaline cycle... Here is a summary of a paper by Durack and Wijffels. http://www.sciencedaily.com/releases/2010/04/100416094050.htm Regarding #34 and #39, also, if the warming were being caused by from-within, electromagnetic interactions between the sun and the earth, I'd expect that this would be detectable by measurements of deep mine temperatures. To my knowledge, there are several rather deep mines in the world, but I've never heard of a warming trend over time with them. Warming trend with depth; yes, but not over time. @ #32, Sorry, but I'm going to guess that what you are missing is an understanding of how statistics can be used to distinguish between sampling differences that are simply a result of random noise and those that are noisy, but are some measurable probability of being caused by real differences in the data sets. I took stable to mean that the standard deviation did not vary much over time; if that is right, then more sample data will lead to less probability that observed mean differences are merely noise, not greater. Yes, technically, any model which can not make 100% accurate predictions can be said to be incomplete. I don't know of any model, even most of the basic physics ones, that can do this. (For instance, we've all been taught in beginning science courses that projectiles follow the path of a parabola; that is a fundamentally flawed model, but it's still useful.) That does not mean that models are without use. The whole point of this discussion is a question of how might this model be better completed. -
Berényi Péter at 01:28 AM on 20 April 2010Tracking the energy from global warming
Well, net radiation balance at TOA (Top of Atmosphere) as measured by ERBE & CERES satellites is 2 ± 5 W m-2, that much we know. Unfortunately this outrageously inaccurate value is quite useless for checking OHC history reconstructions. Toward Optimal Closure of the Earth's Top-of-Atmosphere Radiation Budget Journal of Climate, Feb 1, 2009 by Loeb, Norman G, Wielicki, Bruce A, Doelling, David R, Smith, G Louis, Keyes, Dennis F, Kato, Seiji, Manalo-Smith, Natividad, Wong, Takmeng OHC measurements, at least for the upper 700 m are more accurate during the last couple of years. ARGO only accomplished its 3000 floats target in 2007, but coverage is reasonably good since 2005. So. The discrepancy is not between net radiation balance at TOA as measured by CERES and OHC as measured by ARGO, but between OHC measurements and computational model predictions. In cases like this the standard pre-postnormal science procedure is to abandon model and stick to measurement. -
Tom Dayton at 01:19 AM on 20 April 2010Tracking the energy from global warming
RSVP, the amount of heat leaking to the surface from the Earth's interior is not merely an assumption. It is known to be very small relative to the heating from greenhouse gases. See the references I linked in my comment of 9:28 a.m. and the following one, on the thread Volcanoes emit more CO2 than humans. -
VoxRat at 00:51 AM on 20 April 2010Tracking the energy from global warming
#36: "There still remains one way to balance the energy budget and that is to accept the observed red line in figure 1 is also the actual energy budget. But I guess that raises too many uncomfortable questions!" How is that "balancing the energy budget"? The red line represents a cumulative estimate of where all the incoming goes... If you choose to ignore the satellite data on incoming and outgoing radiation, how do you estimate the incoming energy to balance against it? -
HumanityRules at 23:48 PM on 19 April 2010Tracking the energy from global warming
The Pielke/Trenberth exchange continues here -
HumanityRules at 23:40 PM on 19 April 2010Tracking the energy from global warming
Here's a couple of reviews from Trenberth and Cazenave which focus on sea level rise. Trenberth remains skeptical about the most recent data while Cazenave seems to have a more faith in the numbers. I think Cazenave makes a plausible case for the numbers in Table 1 of her review (page 7). Marcel Bökstedt point about deep ocean expansion is raised by Trenberth but isn't quite the issue Marcel suggests it might be and can't explain away the lost energy. Trenberth still has to come back to faulty ocean data even though several lines of approach confirm the lack of thermal expansion in the most recent data. Just on the question of lag raised by thingadonta. I think this is only an issue when you are measuring either atmosperic or ocean parameters alone. If your measuring both simultaneously it doesn't really matter where energy is building up or whether there are shifts in the rate of transfer between the two systems. It has to be observable somewhere and at the moment it isn't. Piekle makes a good point that total energy is a better parameter for understanding whats going on compared to global mean temperature for this very reason. There still remains one way to balance the energy budget and that is to accept the observed red line in figure 1 is also the actual energy budget. But I guess that raises too many uncomfortable questions! -
Ken Lambert at 23:11 PM on 19 April 2010Tracking the energy from global warming
I have read some of the Willis and von Schukmann papers and it is not easy to understand their exact methodologies for correcting the temperature data from their 'tiling' the oceans and then measuring the heat content of each tile. A tile might be eg. 200m deep x 5nm x 5nm (nautical mile) or some such volume – but have made the point before that unless an instantaneous snapshot at Time1 was compared with a snapshot at Time2 of the whole volume of the oceans (all the tiles) then it would seem hard to measure an accurate difference between the OHC increase or decrease between Time1 and Time2. eg. for major currents like the Gulf Stream – running at 4-5 knots could move heat from one tile to another in minutes to hours. I would think that the Argo buoys would have to measure all at the same instant – eg. 12.00 noon GMT at Time1 and then at Time2 and a buoy would have to be in each 'tile' at the two reference points in time for that data to be useful. Since the Argo buoys are not tethered to a particular spot in the ocean, and move with the currents, would they tend to coagulate in warmer or cooler currents than calmer waters? and what happens to the data from a 'tile' location reporting temperatures at Time1 when it has no buoy in it to report at Time2? -
RSVP at 23:09 PM on 19 April 2010Tracking the energy from global warming
I never understood the explanation for why the Earth's inner mantle is so hot. Supposedly, all that pressure due simply to gravity makes for heat, but pressure in-and-of itself does no produce energy. Pressure on the increase in a fluid does, but if the pressure is static, it is not clear to me how this produces heat. I bring this up in the context of global warming as volcanic energy is assumed to not form a significant part of the radiate model as so far explained at this website, but in terms of something that could change over time, it seems suspect, perhaps accounting for "missing energy". With erupting volcanoes and earthquakes currently going on around the world, it seems this heat varies over time and is not constant. The fact that the Earth is a giant metal ball spinning in the magnetic field of the Sun should tell you something. A situation that should theoretically lead to electrical currents that in turn produce heat. And given that the Sun magnetic field changes with time, perhaps all this could explain the fluctuations we observe. -
thingadonta at 22:46 PM on 19 April 2010Tracking the energy from global warming
#19 "How you know global heat transfer is weakest and slowest between the deepest oceans and everything else"? Ever dived into a deep lake in the middle of summer?, it gets significantly colder as you go down because the surface warms much faster; warm water also rises and cold water sinks-creating long term stratification that isn't easily budged by further input of heat at surface. In fact with time the T divergence between the surface and deeper water can increase, until a point is reached whereby heat transfer can overcome this gravity-related stratification. The important factor is the time involved. The stratified water column resists heat transfer, and the time scales involved since 2005 are too short for the missing heat to be 'going into' deep oceans. Upwelling and downwelling currents are also much too slow to be transferring additional heat from surface to ocean depths in the matter of years. I suspect the explanation of the divergence in Figure 1 lies in some sort of time lag between net radiation and heat transfer,and that the figures are mostly accurate, and that net radiation might start to decline, as it does at the very end of the graph. -
thefrogstar at 21:21 PM on 19 April 2010Tracking the energy from global warming
The blog appears to faithfully reproduce the published article, but I think I'm missing something here. "....satellites which measure both the incoming sunlight and outgoing radiation. The absolute energy imbalance is too small to be measured directly." -So the simple calculation of Energy 'Out' subtracted from Energy 'In' can't be done because the errors of measuring the two are large, relative to the difference between them? "However, the satellite measurements are sufficiently stable from one year to the next so it's possible to track changes in the net radiation". -Isn't this the exact same calculation: "Net Radiation" is the difference between radiative energy 'In' and 'Out'? If the measurements are "stable" how does this make them better? ....Or are they just collecting data over a longer time period to get a better statistical grasp on the data? If this is the case, won't the signal-to-noise ratio only increase as the square-root of the time period? Separately, a third expanation: Might "a divergence problem, if you will" be due to a model which is incomplete, if you will? -
Marcel Bökstedt at 20:40 PM on 19 April 2010Tracking the energy from global warming
SNRatio> Yes, it seems that the expansion of water per added unit of heat is about twice at big at the surface as in the deep ocean, so if we (A) believe figure 1, (B) believe that all that missing energy went into the deep ocean, we would conclude from looking at figure 1, taking into account that the upper ocean is warming at a slower rate now, that the rise of sea level should have been approximately constant since 2005. This ignores the additional effect of melting glaciers. -
SNRatio at 20:20 PM on 19 April 2010Tracking the energy from global warming
27.Marcel Bökstedt at 18:37 PM on 19 April, 2010 Berenyi Peter> It seems that Trenberth does exactly this calculation, and gets that if the "missing energy" (0.9 W/m^ 3) were deposited in the ocean below 700 meters, it would rise the sea level by 1.3 mm/y. ---- May this be an explanation why we have had a continuing sea level rise in spite of very little surface temp increase 2000-2010, and only a fraction being explainable by ice caps/glaciers melting. -
Marcel Bökstedt at 20:06 PM on 19 April 2010Tracking the energy from global warming
thingadonta> I think that we don't really know the amount of heat transfer between the top of the sea (say the top 700 meters) and the rest of it. I'm not saying that there must be a significant transfer, but I can't see how we can rule it out - how do you know that "global heat transfer is weakest and slowest between the deepest oceans and everything else"? -
thingadonta at 19:35 PM on 19 April 2010Tracking the energy from global warming
There is insufficient heat transfer between the atmosphere, land and oceans on annual and interannual time scales for net radiation measurements and calculated heat contents to be in agreement, even if the calculated heat contents are correct. This means there will be a time lag between the two, which becomes most apparent after an inflexion in either trend. If the rate of warming has indeed slowed, and there is no 'missing heat' in the deep oceans, net radiation is lagging the decreased rate of warming and the two lines in Figure 1 diverge, and are correct as they stand. They should eventually re-align. Also, note that global heat transfer is weakest and slowest between the deepest oceans and everything else, so it is even more unlikely that this 'missing heat' is going into the deep oceans in the short time scales involved (ie years to several years). If this explanation is correct, it also contradicts at least some of the standard assumptions about climate sensitivity to greenhouse gases. Neither declining rates of warming, nor the divergence in satellite measurements of net radiation and modelled earth heat content should be happening if greenhouse gases are physically doing what the IPCC says they should be doing. -
Marcel Bökstedt at 18:37 PM on 19 April 2010Tracking the energy from global warming
Berenyi Peter> It seems that Trenberth does exactly this calculation, and gets that if the "missing energy" (0.9 W/m^ 3) were deposited in the ocean below 700 meters, it would rise the sea level by 1.3 mm/y. An imperative for climate change planning: tracking Earth's global energy . -
Marcel Bökstedt at 18:10 PM on 19 April 2010Tracking the energy from global warming
Berenyi Peter> That is a good point, maybe we can start quantifying? It seems you know this stuff, so perhaps you can offer an estimate on the sea level rise which would be caused if the "missing energy" was hiding in the deep sea? -
Berényi Péter at 16:58 PM on 19 April 2010Tracking the energy from global warming
#24 Marcel Bökstedt at 16:28 PM on 19 April, 2010 the temperature of the deep ocean is close to that minimum, so that its thermal expansion coefficient is close to zero A common misconception. Equation of state for sea water is rather tricky. At high pressure volumetric thermal expansion coefficient is positive even at 3 °C. -
Marcel Bökstedt at 16:28 PM on 19 April 2010Tracking the energy from global warming
Humanity Rules> The argument about sea level rise is nice, but has to be analysed a bit. The expansion of water under heating is not constant, it depends on the temperature you start with. The minimal volume and highest density is reached at 3.98 C. I understand that the temperature of the deep ocean is close to that minimum, so that its thermal expansion coefficient is close to zero, which means we cannot use sea level to restrain the temperature of the deep ocean. I think. -
James Wight at 16:13 PM on 19 April 2010Tracking the energy from global warming
This seems to be quite a mystery. I wonder if it could have anything to do with the Pacific Decadal Oscillation (which appears to have switched to a "cool" phase). -
yocta at 15:26 PM on 19 April 2010Tracking the energy from global warming
RE#21 garythompon. I think you may be looking at the wrong paper. The paper you have linked is titled "Global warming due to increasing absorbed solar radiation" K.E. Trenberth, J.T. Fasullo. Geophys. Res. Lett, 2009 Reference 5 in the paper discussed above is titled Earth's Global Energy Budget K. E. Trenberth, J. T. Fasullo, J. Kiehl, Bull. Am. Meteorol. Soc. 90, 311 (2009) . which can be found here -
garythompson at 14:29 PM on 19 April 2010Tracking the energy from global warming
the following statement in the trenberth paper says "Increasing concentrations of carbon dioxide (CO2) (see the figure) and other greenhouse gases have led to a post-2000 imbalance at the top of the atmosphere of 0.9 ± 0.5 W m–2 ( 5);" going to reference (5), i looked at that paper and couldn't find that in it. can someone point me in the right directions and let me know what i missed? and i apologize if the link doesn't show as embedded. i followed the style as listed on this website but for some reason it didn't show right in the preview. i'll keep working on that..... -
scaddenp at 14:08 PM on 19 April 2010Flowers blooming earlier now than any time in last 250 years
"weather has cycles". But the papers under discussions are talking about trends not cycles. -
HumanityRules at 14:02 PM on 19 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
53.Philippe Chantreau I don't think understated just stated. The mass balance has probably been in negative territory (with a few interruptions) since the 1750's.
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