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Comments 59351 to 59400:

59351. Riccardo at 20:49 PM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       Arrhenius was right (and lucky) because the emission layer is inside the troposphere. In fact, Arrhenius' results have been confirmed by Hulburt some decades later by taking into account the temperature structure of the troposphere-stratosphere and the effect of water vapour, CO2 and Ozone. On passing, even a cursory analysis of the temperature structure should tell why the stratospheric temperature follows the insolation annual cycle.
59352. The Inconvenient Skeptic at 20:39 PM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       Daniel, That you need a citation for Phil Jones most influential work is unexpected, but here you go. SURFACE AIR TEMPERATURE AND ITS CHANGES OVER THE PAST 150 YEARS P. D. Jones, M. New, D. E. Parker, S. Martin, and I. G. Rigor
59353. The Inconvenient Skeptic at 20:22 PM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       Thank you Ari. Seasons are not caused by GHG's. So Daniel still has not answered the question of why the stratosphere's temperature cycle is de-coupled from the troposphere on the seasonal scale which is the point that I have been making the entire time.
59354. Ari Jokimäki at 18:51 PM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       I would like to point out that it is not expected that GHG warming, which works in decadal timescales, should be clearly evident in seasonal cycle of stratospheric temperature. Everybody knows that Earth's seasons are due to Earth's orbital parameter changes, but it has nothing to do with GHG warming.
59355. DouglasM at 18:03 PM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       Well, Holgate is not a Climate Scientist. He is, however, an expert (with relevant Doctorate) in Oceanographic Mean Sea Level research, is fully peer reviewed and, as far as I know, his published work has not been challenged. Sounds pretty authoritative to me! I certainly would not want to fly in a plane that had been built using incomplete & proxy data.
59356. Miriam O'Brien (Sou) at 17:27 PM on 30 April 2012
       John Nielsen-Gammon Comments on Continued Global Warming
       Thank you - this is a good way to demonstrate the trend - particularly as so many people who are still (genuinely) sceptical seem to be unable to read graphs. (In my experience if someone says a chart shows a downtrend some people believe them, even when the trend is clearly upwards). FYI, the latest (24 April 12) ENSO wrap up from the Australian Bureau of Meteorology states:

       "Some, but not all, climate models note an increased risk of El Niño conditions evolving during winter or spring. Historically, about 70% of two-year La Niña events are followed by neutral or El Niño phases."

       If so, maybe next year will set another global surface temperature record.
59357. Realist at 17:26 PM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       Chriskoz, So believing we have too many people for a healthy earth means that person is a climate change denier? As you state sustainability is possible with the current population. However that is not a meaningful assessment because population is growing at a greater rate than ever with 14 plus billion to be added in the next hundred years. So either the solutions need to consider 21 to 30 billion with a higher average standard of living than today as the energy requirement to be achieved, or controls on the population level to keep it to current levels, or reduce it from here.
59358. skywatcher at 15:54 PM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       DouglasM - Indeed, the burden of proof lies with the authors of an hypothesis. In this case, the burden would lie with the author of a paper, or those who interpret it as such, whose conclusions lie contrary to those of the wider science community. Unfortunately for you, the evidence of just nine stations is pretty weak versus hundreds plus a satellite record. Even Holgate says there's no statistical significance in the difference between SLR rates in the early and later part of the century from their data. A CERN thought - why would a CERN talk be authoritative on sea level or climate science? Sure CERN's probably a great place to hear about particle physics. But would my local zoology department be the place to hear authoritative talks on particle physics? What makes you think a speaker at CERN is authoritative on climate science? They could be, but that probably does not depend upon their presence at CERN. We're still left with why you consider this single paper "most authoritative"? Don't trust models? Ever got in a car, bus or plane?
59359. DouglasM at 15:18 PM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       Hmm, that's Hermie talk. Just for some light relief, read Clive James from a few years back: http://www.clivejames.com/point-of-view/series6/hermie The burden of proof in science is always with the authors' of a hypothesis, not those who question it!
59360. scaddenp at 15:04 PM on 30 April 2012
       How Increasing Carbon Dioxide Heats The Ocean
       Truckmonkey, your comments about sea being "warmed by the atmosphere" seemed to imply you were thinking of conductive or convective heating, not radiative heating. If this is not so, then no issue. Also, the issue of skin layer The cool skin was raised in the last of the series.
59361. trunkmonkey at 14:37 PM on 30 April 2012
       How Increasing Carbon Dioxide Heats The Ocean
       Scaddenp-OK I read it, including the comments. Don't see any basic misunderstandings. What I do see is that something so apparently simple as heat transfer between the ocean and the atmosphere pushes us beyond our understanding of the physics.
59362. Daniel Bailey at 14:03 PM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       TIS, the topic of this thread is Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930. Thus, your objections are not on-topic on this thread. If it is your intent to contest Stratospheric Cooling and Tropospheric Warming, then take it there. Or is it perhaps more straightforward, like contesting the Enhanced Greenhouse Effect, then take it there. For the lay reader, a good overview of the whole thang can be found on the How we know we're causing global warming in a single graphic thread. Again, all fundamental stuff. Not contested or in "debate". Your Phil Jones reference lacks a citation...and an explanation as to why it should be considered to be anything other than an off-topic, inconvenient diversion.
59363. chriskoz at 14:02 PM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       Realist and others who discuss population factors, Washington/Cook "Climate change denial" book on the right margin actually discusses the overpopulation problem as one of the topic of the denial. Reread the appropriate chapter and the references therein. Essentially, the sustainability experts quoted state, that with current population of 6-7bilion can sustain current level of comfort with some behavioural adjustment, with all natural sources 100% renewable. The mandatory condition is population stabilisation at current levels. Denial of that condition is, according to authors, equal the denial of AGW reality: stabilisation of climate in particular and sustainability in general is impossible without population stabilisation.
59364. The Inconvenient Skeptic at 13:43 PM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       You are correct that I mis-typed that the Sun (meant Earth) receives the least energy in July. Thanks for noticing that. Jumping to the point then. If it isn't the solar energy that is causing the phasing of the stratospheric temperatures, then what is? I welcome an explanation of how GHG's manage to cool the stratosphere while the Earth is warmest and vice versa. Unless of course you are discounting all the work of Phil Jones that shows the Earth's maximum temperature is ~16C in July while it is ~12C in January.
59365. Daniel Bailey at 13:32 PM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       "As usual the readers on this site focus only on anomaly which is why they consistently miss the point." The readers of this forum focus on the peer-reviewed literature published in reputable journals. They also focus on debunking the memes promulgated by fake-skeptics... "The stratospheric temperature that I show is the average daily temperature for the past 9 years." And thus utterly lacking in any significance, statistically. "The stratospheric temperature is directly dependent on the amount of energy the Earth is getting from the Sun." You conveniently omit it is also directly dependent upon the amount of GHG's present in the atmosphere. And upon the levels of CO2...directly. "The means in January the Earth gets the most energy and in July the Sun gets the least energy. " You may want to revisit this assumption. Unless you are implying the Sun receives back radiation from the Earth... "This would indicate that the amount of CO2 can have no impact on the upper atmosphere." Utter Horse-hockey. That the stratosphere's temperatures can be affected by levels of CO2 is foundational to GHG functionality. Another point utterly without debate by those who understand the science. "Ignoring the facts in this case is pointless because there isn't a debate on this. " Correct. That you are wrong is a fact, without debate. And that the facts are inconvenient to the agenda you consistently prosecute is also not contested. As usual.
59366. chriskoz at 13:30 PM on 30 April 2012
       2012 SkS Weekly Digest #17
       The slightly OT news: Dr Michael Mann just received the coveted Oeschger medal award as reported in realclimate. Most of SkS "long-timers" probably visit realclimate, however newbies might not so I stuck this news here rather than in somewhat more relevant thread about Mike's book. If you think you can contribute to the well deserved congrat thread you are encouraged to do so. As the scientist who withstood the worst personal intimidation in recent history, Mike deserves every bit of recognition for his work and his stance.
59367. The Inconvenient Skeptic at 13:20 PM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       As usual the readers on this site focus only on anomaly which is why they consistently miss the point. The stratospheric temperature that I show is the average daily temperature for the past 9 years. Temperature (not anomaly) changes over the course of the year. What causes the actual temperature to change is what I am discussing. The stratospheric temperature is directly dependent on the amount of energy the Earth is getting from the Sun. Over the course of the year the Earth's distance from the Sun changes. That is the dominant factor in determining the amount of energy the Earth is getting. The Earth is farthest from the Sun in July and closest in January. The means in January the Earth gets the most energy and in July the Sun gets the least energy. The stratospheric temperature reflects that same behavior while the Earth's surface does not. Arrhenius stated that in the upper atmosphere (i.e. above the level where water vapor exists) that an increase in CO2 would not be impacted by that water vapor. I am simply pointing out that the stratosphere shows no dependence on the Earth's surface. This would indicate that the amount of CO2 can have no impact on the upper atmosphere. Ignoring the facts in this case is pointless because there isn't a debate on this. I am simply pointing out that the article states the response to Arrhenius, but fails to mention that the temperature of the stratosphere is independent of the surface and the troposphere. Of course Arrhenius didn't know that when he said it, but the author should have known that.
59368. Bob Lacatena at 13:07 PM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       42, scaddenp, Funny you should say that. Just the other day I was thinking that denial science is the science of hope. So far, denial scientists have been unable to prove anything more than that they hope that climate sensitivity is low. Spencer, Lindzen and others keep looking for ways to prove it, but failing. They also continue to ignore the preponderance of evidence that says otherwise. In the end, they can't prove that climate sensitivity is low, so they hope that it is low, and hope some day to be able to prove it. The same goes for deniers who cry "fraud" or distrust (a) climate scientists (b) models (c) the surface temperature record (d) tree rings and proxy studies or (e) anything else that is inconvenient. They can't actually prove anything. All they can do is to claim that "method x" is untrustworthy, and so it doesn't prove anything, either. And, in the end, they are left with the nothing but the hope that they are right.
59369. muoncounter at 12:43 PM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       Realist#14: "more humans equals more human caused global warming..." On the surface, that statement seems to make sense. However, it is rooted in correlation-implies-causation. Blaming it on people is a dead end - and off-topic for this thread. An industrial society that grew up enjoying profligate fossil fuel use without regard for its waste products is a more sensible cause for warming. It is the fear of a threat to this lifestyle - and fear is exactly what the deniers exploit - that results in the 'we can't afford' anything different response. Bernard J#16: "It's what we do with all of our energy usage that is more to the point" Consider this: we don't have lots of time to debate the changeover from fossils to renewables before the wheels start to come off. I live in a state where summers bring rolling brownouts when generator operators find that their cooling water ponds are too hot - and the same plants are shut down in winter when their water intake pipes freeze. If we continue to do nothing while we debate the end game, these problems will only grow more severe and more frequent. This makes shifting the discussion to a reorganization of energy consumption by society at large seem like a luxury.
59370. scaddenp at 12:37 PM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       Dave123 - I would be curious about your source for: "The waste heat contained in the slag from steel production is on the order of 2 Terawatts. The largest single windturbine made by one supplier I paid a call on is 6 Megawatts. The heat contained in the slag does not count the heat contained in the steel...another matter." "contained" is perhaps not the best choice of words. Nor is a Terawatt a measure of energy. MECS data for energy use in steel production (cost of mining and transporting materials; energy conversion in raw product; and energy for processing) looks good to me and 2003 figures would work out at around 13GJ/tonne. A 1.5MW turbine might weigh 60 tonne. It should generate the energy cost of create it in 145 hours of generation.
59371. Bernard J. at 11:26 AM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       Muoncounter. When I said "How will it all fit on the planet?" I was speaking in terms covering more than just the business of renewable energy production. It's what we do with all of our energy usage that is more to the point - energising those post-energy production processes is just a part of the problem. Dave123. You've listed several large numbers, but that doesn't mean that they would mesh to give a product that would sustain a continuance of current Western society, especially if it were to be extended in the future to the 'Other 80%'. Here's an exercise for you. 1) For each country of the world list the amount of energy used per capita for (a)transport; for (b) heating/lighting/other household power; and (c) for food, for other consumables, and for infrastructure manufacturing* and maintenance/replacement. 2) For each of these countries, calculate how much can be supplied by renewables within their own borders, in a fashion that does not threaten the ecological intregrity of the respective nations. In conducting this calculation, partition the renewable energy into the three broad fields listed in the previous point, and include all of the process losses in converting renewable energy into a form that is employable for each of those broad fields. 3) Where renewable energy cannot be supplied within a nation's own borders, or where the resources for converting raw garnered energy into a storable and usable form are not available within a nation's own borders, determine how and where the shortfall will be addressed. 4) Once you are satisfied that you can fuel current Western enterprise indefinitely into the future (I would love to see such numbers...), turn you gaze to the downstream consequences of current energy supply. At current (and extrapolated, based on further industrialisation) trajectories of global resource use, how will water resources respond to humans persisting with our current energy use? Topsoil? Fisheries? Forestry? And what about that more abstract notion - biodiversity? How will biosphere feedings-back affect our global extraction of natural resources? As an example there's a disturbing indication that oceanic plankton stocks are decreasing in response to human chemical and thermal impact on the marine environment. Do you understand how, in this example alone, the trophic cascades will operate? Do you understand how the numbers above will be affected by such ecosystem changes? I've collated a lot of the numbers for all of the above myself, but I think that this is an exercise best left to the individual, at least in the context of this discussion, so that those who are not familiar with the system-level significance might actually learn to comprehend the issue. Down the track I hope to summarise some of the figures as quantities in tables and graphs - if I don't first come across others' work showing the same sort of things. Please, and I am earnest in this, take the time to actually learn about and compare the numbers yourself. Don't just look at a list of big numbers, because they are static and disconnected values that do nothing to inform about the overall situation. Remember, this is about thermodynamics, and the 'dynamic' part of the equation seems to be too often swept over in the discussion, to the detriment of the overall conclusion derived from such cursory considerations. [*Note: in this category I include mineral extraction. As humans exhaust the most easily sources for each and every mineral that we use, more energy will be expended to extract material from ever-decreasing quality of substitute sources. Your calculations for (c) should account for the future increasing energetic cost of mining ever-poorer sources of minerals, and for process replacement where it simply becomes impossible to sustain a particuar mining enterprise under the cost of ever-diminishing returns).]
59372. KR at 11:17 AM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       The Inconvenient Skeptic - "The problem with Arrhenius's upper atmospheric response is that stratospheric temperatures are..." Are you aware that Arrhenius published "On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground" in 1895, while the stratosphere itself was not discovered until five years later? With detailed knowledge of stratospheric structure and response coming after that? Arrhenius can hardly be blamed for not detailing changes (such as stratospheric cooling with increased GHG concentration) before anyone knew about the stratosphere. Add to that what muoncounter pointed out - that your objection regarding insolation and stratospheric temperatures has no basis in fact - and your post objecting to Arrhenius is quite, um, curious...
59373. scaddenp at 10:24 AM on 30 April 2012
       How Increasing Carbon Dioxide Heats The Ocean
       truckmonkey - it looks to me like some basic misunderstandings here. Have a look at Does back-radiation heat the ocean series at SoD.
59374. scaddenp at 10:14 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       "Don't trust models I'm afraid." What do you trust as a way to estimate what happen in the future? Extrapolation? Hope?
59375. scaddenp at 10:12 AM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       "at least triple"?? UN estimate is 10.1 billion by 2100. Where does your estimate come from? But, yes, I do agree with IPAT formula (Impact = Population * Affluence * Technology).
59376. Tom Curtis at 10:11 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       DouglasM @35, Holgate's 9 station reconstruction understates the figures for his 177 station series for the last decade of the twentieth century, but overstates them for the first decade of overlap: Holgate's 9 station reconstruction also disagrees markedly with both Jevrejeva 2008 and Church 2006 over the period from 1900 to 1920. Holgate shows sea levels rising at near 4 mm per year over most of that period, before dropping to 0 mm per year in 1920. Both Jevrejeva and Church show the sea level rising from 0 mm per year in 1900 to just below 2 mm per year before falling back to below 0 mm per year in 1920. This comparison, by the way, give the lie to your claim that Holgate is the "most comprehensive because the sampling covered the whole 20th century". Church and White 2006 sampled from Jan 1870 to Dec 2001. Jevrejeva et al, 2008 sampled from 1700 to 2002. Whether considering the number of stations, or the duration sampled, both studies are easily more comprehensive than Holgate 2007. But again, and this appears crucial in your assessment, it gives the result you want and therefore its significance must be overstated so that you can ignore the barrage of results you don't like from other sources. Turning to your throw away comments. (1) Evidence that sea level rise correlates with increased temperatures (which is very strong) suggests that in the 21st century when global means temperatures are expected to rise from 2 to 5 degrees centigrade, sea levels will rise much faster than they have in the twentieth. Suggesting that mere correlation trumps physics (as your comment does) is simply asinine. (2) That you first learnt of Holgate at a CERN lecture, unfortunately, does not these days mean you did not hear it from a denier source. And certainly the statement of an unnamed source at CERN does not make Holgate 2007 more comprehensive than other studies with far better sampling over far longer durations. Of course, as always, deniers are quick to appeal to argument by authority whenever the "authority" gives them conclusions that suite their politics.
59377. Daniel Bailey at 10:06 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       "Don't trust models I'm afraid." Barring absolute certainty, every decision one makes is based on a "model". You propagate a meme long since debunked on this site.
59378. Daniel Bailey at 09:56 AM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       "Apples to apples?" That would be an inconvenient comparison, as in it inconveniently lacks straw...
59379. Realist at 09:50 AM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       While it is easy to talk about m2 of solar panels per person, this becomes a frightening prospect with the worlds population set to at least triple in the next hundred years. At what point is the fact that more humans equals more human caused global warming going to be considered? From what i see all solutions tend to assume the current population level will remain, and do not incorporate population growth into the solutions.
59380. muoncounter at 09:45 AM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       TIS: That's an odd comparison, plotting stratospheric temperature against surface solar radiation (~340 W/m^2). Why not show the stratospheric temperatures against the TOA solar constant? Apples to apples? -- source Looks like more than 0.5 degree down over 25 years. Looks like a very small net variation over the same time frame.
59381. DouglasM at 08:44 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       Scaddenp, don't think Dr Holgate would like to think he was being used by pseudo-sceptic blogs, he's certainly no sceptic. First saw the Holgate results (among others) in a CERN lecture, and it was considered the most comprehensive because the sampling covered the whole 20th century! Don't trust models I'm afraid.
59382. The Inconvenient Skeptic at 08:28 AM on 30 April 2012
       Two Centuries of Climate Science: part one - Fourier to Arrhenius, 1820-1930
       The problem with Arrhenius's upper atmospheric response is that stratospheric temperatures are primarily a direct response to the solar constant and it's variation over the course of the year. The amount of energy that reaches the stratosphere from the troposphere is limited. This leaves the Earth's distance from the Sun as the primary driver of the stratospheric temperature variation. The coldest stratospheric temperature also took place in mid-2008 when the Sun was unusually quiet and the Earth was the maximum distance from the Sun. Since the Sun has become more active, stratospheric temperatures have increased. If the upper atmosphere's temperature isn't impacted by the CO2 absorption, it would appear as if Ångström was in fact correct, even if his measurement was not perfect by today's standards.
59383. scaddenp at 08:09 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       Douglas, I am not doubting the Holgate paper's analysis of 9 stations. I am questioning your assessment of it as "the most comprehensive" especially when it is not (as you have been shown). Does "generally recognised and often quoted" really mean "lionised on pseudo-skeptic blogs"? I was asking where you got that assessment of the paper from because your source is clearly wrong and you should know that before trusting that same source for other information. Also before deciding that data contradicts model for sealevel you should see what the science actually expects sealevel rise to be and rate of acceleration (eg Vermeer & Rahmsdorf. See also the discussion here and note the acceleration when you look at the longer century-level time line.
59384. Killian at 07:31 AM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       @#10, 11 and 12: The fundamental error here is decontextualizing the issue. It's not just about energy. It's also equally about finite resources, and the list is long. Discussing joules outside of that context isn't all that useful. 2. When discussing energy you have to deal with fungibility. Oil is the single most fungible energy source on the planet. It's truly magical. There are massive losses in terms of what other energies cannot do, and this must be factored in. It will take many more resources to do what oil does. When are we - humanity - going to get around to never decontextualizing the problems we face except when actually designing details? Within the broader context.
59385. DouglasM at 07:27 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       Well scaddenp, Holgate's paper is generally recognised and often quoted, so would have been peer reviewed before publication. Ask the gentleman yourself: Dr Simon Holgate Permanent Service for Mean Sea Level Proudman Oceanographic Laboratory Liverpool
59386. trunkmonkey at 07:24 AM on 30 April 2012
       How Increasing Carbon Dioxide Heats The Ocean
       This skin layer would be cool as a result of either heating the atmosphere above, or from evaporation. Either way it would be thermally unstable, sink, mix and cool the water below. One cannot think of it as an oil slick that stays on top. It is really the mixed layer. It is mixed mechanically by waves and shear at current boundaries. The mixed layer varies considerably in depth, extending to 2000m (Levitus). It can certainly become warmer when it is unable to radiate as much energy to a warmer air mass above.
59387. Riccardo at 07:22 AM on 30 April 2012
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       One thing people often forget is that the atmospheric surface temperature over the oceans is taken equal to the sea surface temperature. By this definition, atmospheric warming can not drive ocean warming. On the contrary, it's the ocean surface layer that drives both the atmosphere and the deeper ocean.
59388. scaddenp at 06:54 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       Perhaps DouglasM you would like to tell us where you got the idea that "S J Holgate's 2007 paper represents the most comprehensive empirical measurement of decadal sea-level change rates during the 20th century." Perhaps not the most reliable source of information?
59389. DouglasM at 06:53 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       Tom, oh no, it's going up 12 inches per century, not 7 inches. Statistical sampling using common and consistent data sources for over one hundred years has a good deal of credibility in establishing trend. If Holgate's observations were supposedly understated for the final ten years, they were likely to be understated by equal order for the preceding 90 years - the trend remains! Some comments by Holgate regarding his paper: "The point of the journal article was to show that global changes in sea level do not proceed smoothly and that there are periods of higher rates of increase along with periods of lower, or even occasional negative change. The paper also shows that the global average sea level has been rising for more than a century, and continues to rise. Sea levels that coastal dwellers experience is affected by local land movements. These movements include the recovery of the Earth’s surface from the deforming weight of ice sheets during the last Ice Age, subsidence due to water extraction, earthquakes and regional plate tectonics. These effects are carefully taken into account when we calculate the global and regional sea-level changes, but these effects may add or subtract from the relative sea level experienced at the coast."
59390. Rob Painting at 05:50 AM on 30 April 2012
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       Trunkmonkey - atmospheric warming does not heat the ocean, it's the other way around - the warming ocean is responsible for the bulk of atmospheric heating. Longwave (heat) radiation cannot penetrate more than a fraction of a millimeter into the ocean. This is why the change in ocean surface layers in the tropical Pacific (the tilting of the thermocline) during El Nino/La Nina has such a dramatic effect on global surface temperatures. See SkS post: How increasing carbon dioxide heats the ocean. The continued warming of the ocean, as Riccardo pointed out above, means there is more global warming 'in the pipeline'.
59391. Daniel Bailey at 05:34 AM on 30 April 2012
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       "atmospheric temperatures appear to be reaching equilibrium" And what are you basing this assertion on, precisely? Plenty of recent posts here at SkS showing the opposite. As for the rest of your comment, I suggest "reading the OP..."
59392. trunkmonkey at 05:20 AM on 30 April 2012
       Levitus et al. Find Global Warming Continues to Heat the Oceans
       Tom Curtis@20 Sure, equilibrium has not been reached for whatever is forcing ocean temperature in the top 2000m, but atmospheric temperatures appear to be reaching equilibrium. If atmospheric warming is driving the ocean warming then ocean temperatures should follow .
59393. Dave123 at 05:19 AM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       Bernard, I feel like I'm listening to Climate Denialist. For me it isn't sufficient to wave thermodynamics around. I've pointed out that for a fraction of our military expenditures (153 out off around 700 million) we could build SOA windturbines for about 2 terawatts of energy per year...or 100 terawatts over 50 years. I generally prefer primary sources to Wikipedia but In 2008, total worldwide energy consumption was 474 exajoules (474×1018 J=132,000 TWh). This is equivalent to an average energy consumption rate of 15 terawatts (1.504×1013 W).[1] The potential for renewable energy is: solar energy 1600 EJ (444,000 TWh), wind power 600 EJ (167,000 TWh), geothermal energy 500 EJ (139,000 TWh), biomass 250 EJ (70,000 TWh), hydropower 50 EJ (14,000 TWh) and ocean energy 1 EJ (280 TWh).[6] Nothing here looks out of reach to me, thermodynamic losses factored in. Please submit references and papers... that's what I hope for from SkS.
59394. NewYorkJ at 03:31 AM on 30 April 2012
       Global Warming Causing Heat Fatalities
       I suspect if human activities were a net cooling effect over the 20th century, deniers would be saying increased cold snaps are a good thing, based on similar 20th century data. Central air conditioning usage through the 20th century has increased, from near zero to around 50%, aside from other cooling technologies. Advanced or central heating has had a similar (if not greater) jump. Most of the former changes are not a result of adaptation to global warming any more than the latter, so using 20th century trends in industrialized countries as evidence that increased heat waves are a good thing for mortality is not supported in the data. Basic cause-effect fail. -1 Chip. Adaptation is not without costs either, particularly burdensome for those who are not currently prepared. For those who are prepared, with AC in their homes, vehicles, and place of work, will heat-related mortality stay constant? This relies on the assumption that no one ever goes outdoors for long.
59395. Daniel Bailey at 03:26 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       DouglasM forgot the /SARC tag.
59396. Tom Curtis at 03:12 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       DouglasM @32, actually, what Lindzen did (among other things) is accuse his colleagues of fraud based on (at best) poorly sourced data which he did not double check. In a more genteel age, such a gaffe would have resulting in his resigning his current paid position in disgrace. In this age where the politics of fossil fuel trumps all sense of ethics, he merely apologizes in terms which accuse the those being apologized to of academic negligence - this time based on no greater evidence than that it would be convenient for Lindzen if it were so. Those politics, and those guided by it, are certainly an example of the GIGO principle. A case in point is your claim that:

       "S J Holgate's 2007 paper represents the most comprehensive empirical measurement of decadal sea-level change rates during the 20th century."

       Really, Holgate 2007 in which Holgate examined the records of just nine stations is a more comprehensive survey than Jevrejeva et al, 2008, in which they examined 1,023 stations; or than Church and White, 2008 who tracked at least 350? It becomes apparent that "most comprehensive" is a trade term for you, meaning something like "has conclusions most suitable to my prejudices". Examining Holgate we find that after 1993 his 7 stations diverge substantially from a 177 station record from a previous study of his. If they had instead tracked the 177 station record, then the highest rate of change in sea level would have been at the end of the 20th century (instead of the 1980's). More significantly, his seven gauge record diverges significantly from the still more comprehensive satellite record of 3.1 mm per year over the period 1993 -2003 (compared to the 3.4 mm per year found by Jevrejeva over the same period). Clearly his "comprehensive" survey of just nine stations must take precedence over his earlier 177 station record, Church and White's 350 station record, Jevrejeva's 1000 station record, and of course the whole of ocean satellite record for that period - at least, that is, if you join with Lindzen and DouglasM in putting the politics ahead of the science.
59397. muoncounter at 03:07 AM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       Bernard J#10: "the energy density of fossil carbon cannot be matched..." Your point is valid if we think only of 'energy density' in classical terms of kiloWatt-hours per cubic meter of source material. Renewables don't necessarily lend themselves to that metric. Think instead in terms of 'energy yield,' a measure of kWh per square meter of surface dedicated to producing that energy. And that leads to another point you raise: "How will it all fit on the planet?" In the full ETOM video, Alley shows that solar/photovoltaic potential alone is a staggering multiple of demand, but he does not fully address the land area requirements of 'harvesting' that low yield crop. A study of photovoltaic systems by Denholm and Margolis 2008 showed that energy yield varies considerably with site location and with array deployment. They derive a range of 100-450 m^2 per person per year as "the PV land area needed to meet 100% of an average U.S. citizen’s electricity demand." Their recommendation was to use 'zero-impact' surface area such as rooftops, a national average of about 65 m^2 of rooftop area available per person in the U.S. Assuming flat deployment, this number would imply that rooftop PV deployment alone could provide around two-thirds of the nation’s electricity supply. Not a bad start, particularly in this context: Golf courses and airports each currently occupy about 35 m^2 per person in the United States
59398. DouglasM at 02:24 AM on 30 April 2012
       Climate Scientists take on Richard Lindzen
       Such vitriol, Dick Lindzen was only trying to draw attention to the obvious scientific risks of relying on computer models - GIGO, or perhaps "Assumptions In, Assumptions Out"! Just one example, sea levels. S J Holgate's 2007 paper represents the most comprehensive empirical measurement of decadal sea-level change rates during the 20th century. Between 1904 and 1953 global sea levels rose by 2.03mm per year, whereas from 1954 to 2003 they rose by only 1.45mm per year, giving an annual mean rate of 1.74mm per year over the 100 years to 2003, or seven inches per century. Importantly, there was no increase in the rate of change over the whole century! Hardly a case for alarm I would suggest.
59399. Bernard J. at 00:44 AM on 30 April 2012
       Richard Alley - We Can Afford Clean Energy
       I fully concur with Richard Alley that renewables can be made competitive in many contexts with fossil fuels. However, I also have some reservations, and although steve from virginia raises some seemingly controversial (and abstruse) ideas, he is pointing to at least one elephant in the room that is directly relevant to the matter of energy substitution. To put it in context: 1) humans have in a blink of an evolutionary eye tapped what is perhaps the most energy-dense source of fuel in the solar system that is easily avilable 2) with this staggering glut of exquisitely finite energy we humans have essentially remodelled our global habitat, and pushed our numbers to full exploitation of this glut without thought for its finiteness 3) the aforementioned finiteness is easily (and increasingly) demonstrated by a simple consideration of high-school level geometric mathematics 4) the energy density of fossil carbon cannot be matched by any renewable source in terms of scale. Taking the last point first, for renewble fuels to be in any way able to functionally replace fossil fuels, they would require extensive deployment both in terms of resources to manufacture the equipment to capture and to store the energy, and in the context of modifying the environment further in order to garner the necessary area with which to harness the energy in the first place (remember, we are talking about what is directly or indirectly diffuse solar energy). This is fine so far, in terms of Alley's correct commentary on the basic technical feasibility, but there are several further considerations that need to be accounted for. First, the second law of thermodynamics dictates that there is an energy cost in converting the harvested energy into a storable form, and that there is an additional cost in subsequently using it. Humans currently do not pay that cost with fossil fuels because it was paid over hundreds of millions of years of fossil carbon formation. Second, the very infrastructure for capturing our current level of energy use requires an energy investment, and the energy return on energy invested (ERoEI) for renewables is not nearly as high as it has been for most of the time that technological society developed using fossil carbon. So, even more energy will be needed to be sourced than is currently used by humans. Now, do we aim to supply current levels of Western energy use to future non-'developed' nations? Think carefully about this, because global warming and energy red-lines are both just links in a greater chain of unsustainability that humans are facing. Even if we magically replace all of our energy needs, and halt warming at today's current commitment, the world still faces many ecological crises built on past usage patterns. And if we try to energise the rest of the world to current Western standards, the resulting pressure on the environment will only increase, and exponentially. Imagine eight or nine billion people using the planet as the richest two billion currently do. Imagine that they're doing so using the intensive renewable energy technologies and resource requirements that would be necessary to sustain so much energy input. How will it all fit on the planet? The simple fact is that it won't, and getting back to my first paragraph, although renewables are potentially cheaper in the near future and on the small scale, compared to fossil carbon, that would change if we tried to globalise them. Renewables are a first step in a much greater change that needs to occur, and that needs to occur principly in the First World. Dave123 likes our civilisation. Personally, I myself am also quite fond of many of its achievements. However, the fundamental issue has nothing to do with what we like, it has to do with numbers. Dave also says that as a "technologist" he doesn't believe in "magic solutions", but the current approach to renewables (and to nuclear, when the microscope is appropriately trained on it) still involves magical thinking - even amongst those who should know that there are thermodynamic implications underpinning the whole story. The fact is, modern industrial society was built on a one-off energy bang that cannot be replicated. Even if technology were to be able to do so, it's almost certain that we've already left it far to late to ensure the transition - not to mention that we've squandered on frivolities too much of the energy that would have been necessary for establishing a future global sustainable-energy infrastructure. And in the process we've overbred and over-FUBARed our planetary life-support system. This is not to say that the future isn't in sustainable energy. If we are to have a future, of course we must go down that path. But as my favourite curmudgeon Albert Bartlett irrepressably points out, it cannot be done at the level of energy/resource use per person that we have currently enjoyed in the West. It just can't. When all of the numbers are accounted for, it is simply not possible to sustain the present level of human energy/resource use, let alone to increase it. Yes, it might be possible to have some high-technology in the future, but the penalty will be an enormous downgrading for the average planetary citizen. Of course, we've shown no inclination to choose this voluntarily, so it's likely that thermodynamics will impose the necessity on us. Peak Oil, with its resultant knockings-on of increasing unemployment, diminishing of funding for expensive domains in science, art, and social weal - teetering economies in general - are the present manifestation of the inexorable tapping on our collective human shoulder that thermodynamics wants us to pay our entropy debt. Our baulking about addressing climate change is, sadly, a part of our procrastination in responding to an even more profound challenge to society. The former is no less important than the latter, but if both are to be affectively addressed it will require some brutal honesty on everyone's part, and this includes those with the best technological solutions - we need to go right back to the basic laws of physics, given that we've painted a planet into a corner and physics now dictates the only way out.
59400. Michael Whittemore at 23:27 PM on 29 April 2012
       ABC documentary demonstrates the how and why of climate denial
       #45 Delmar Firstly I understand we make money off mining but just like we want to ban live meat exports we are going to have to consider the implications of the coal we export. But in saying that if Australia stopped exporting coal, it would drive up the costs for other countries, but mining company's would just move to other countries. What I am saying is that people suggest governments cant stop the CO2 emissions, but we can. If most of the developed world wanted to they could simple get Australia and Brazil to stop exporting coal. This would drive up the cost so much that solar would be more cost affective.

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