Recent Comments

Prev  1564  1565  1566  1567  1568  1569  1570  1571  1572  1573  1574  1575  1576  1577  1578  1579  Next

Comments 78551 to 78600:

78551. Albatross at 03:53 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric, "Taking long average may suffice to convince the naive, but do not try to sell the snake oil to the rest of us." Sigh, now you are engaging in slander and innuendo. Please try and focus on the science. I look forward to your answers to the questions that I posed to you at #30.
78552. Albatross at 03:52 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       EricRed, "In every one of these plots, the increase is significantly less in the past decade, and approaching zero." Ah, there is the rub Eric-- "the last decade". I know that you know better than now. Please do not insult us here with such tired old games and canards. You need to up your game. Now are you here to defend (or distract from) the mendacious acts and distortions of Pat Michaels? It certainly seems so. In fact it appears that you are very much in agreement with him. If not, please state clearly which of his statements/claims you agree or disagree with and why. I'll help, Dana found that: 1) "Michaels committed the dishonest act of equating 'no statistically significant warming' with 'no warming'." 2) "He relied exclusively on CRU temperature data to make his arguments, even though he has previously criticized this same data, because the other temperature data sets do not support the arguments Michaels makes." 3)"Michaels' portrayal of Kaufmann's study was not very accurate, nor were his assumptions about the geographic distribution and effects of aerosols." Number 2 is priceless. After all the claims of fraud etc. made by "skeptics" against CRU by "skeptics", the CRUT data has suddenly become the darling of the "skeptics". Could it have anything to do with the fact that it is known to run cool....nah ;) But then again, recall how the "skeptics" were big fans of the UAH data until it started showing warming.
78553. Eric the Red at 03:47 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Bibliovermis, I agree with the statement that greater warmer was observed in the 1990s. That is exactly what you are protraying with your 10-year moving average. The 10-year moving average peaked in July 2002, with the greatest increase occurring from 1/1995 - 1/2000. You can play with statistics all you want until you arrive at your desired conclusion. [-Snip-]
       Response:

       [DB] Inflammatory snipped.

78554. KR at 03:42 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric the Red - "the increase is significantly less in the past decade, and approaching zero." From the GISSTEMP data: Temp. anomaly from 1951–1980 mean: 1980–1989 0.176 °C (0.317 °F) 1990–1999 0.313 °C (0.563 °F) [ +0.137 °C ] 2000–2009 0.513 °C (0.923 °F) [ +0.200 °C ] The decade by decade numbers say otherwise - temperatures are increasing at an increasing (higher than linear) rate for the last 30+ years. The year by year slope isn't meaningful - decadal averages are better, 30 year trends are statistically useful. You are incorrect, again, on this subject.
78555. Bibliovermis at 03:31 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric the Red, This is a broken record. Stop eyeballing a few pixels and crunch the numbers. We went round and round on this topic back on the Why Wasn't The Hottest Decade Hotter? article. The 2000s were warmer than the 1990s by a larger margin than the 1990s were warmer than the 1980s. Using a 10-year moving average with annual frequency, the last 10 decadal-periods have been the hottest ten with 8 of those 10 having an above average (of the past top 28) temperature change. As Dikran points out, short term trends are not robust. Temperature charts are not Rorschach tests.
       Moderator Response: [Dikran Marsupial] Link fixed
78556. Dikran Marsupial at 03:14 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric the Red the human eye is very good at finding what it wants to see in noisy datasets, which is why we have statistics. Given the level of noise in the dataset I suspect the decrease in the slope of the trendline is unlikely to be statistically significant. I can't believe that people are still using variants of the "no warming since 1998" canard. Short term trends are not robust, so you can't reliably detect a genuine decrease in slope from one decadal trend to the next.
       Response:

       [DB] ETR has tried to pull this wool over SkS eyeballs several dozen times now, without success.  It grows tiresome.

78557. Eric the Red at 02:57 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       KR, You may want to look at this. http://www.cru.uea.ac.uk/cru/info/warming/ or this. http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.gif or maybe this one. http://www.woodfortrees.org/plot/wti/from:1975/to:2011/plot/wti/mean:60 In every one of these plots, the increase is significantly less in the past decade, and approaching zero.
78558. garethman at 02:26 AM on 27 July 2011
       Gripping video of Arctic sea ice melting away before your eyes
       It’s a great piece of video and technology. Wattsupwiththat also posted it a couple of weeks ago, though puzzlingly without any contention by posters, just a sense of wonder. Some of the bouys however have stopped working and some give a good view of a workshop. Hopefully they will be up and running again soon. I wonder if they float the right way up?
78559. dana1981 at 01:52 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Loehle and Scafetta would benefit from reading Dikran's comment #20. The physically baseless curve fitting we're discussing here, and which was done in Loehle and Scafetta's paper, will be the subject of a future post.
78560. KR at 01:34 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric the Red - The differences in decadal temperatures are increasing since the 1970's: see the plot here. That's a faster than linear increase, contrary to your post here. Secondly: "The data would best be described as a sine wave about a linear trend." Actually, no. The data would best be described as the response of the climate to multiple changing forcing factors. "A sine wave about a linear trend" is a descriptive term, but absolutely not an explanatory statement, as it has no ties to climate physics whatsoever. That's an eyeball judgement (eyecrometer?), not an understanding of the processes involved. Tamino's term for this, having actually analyzed whether there are periodic behaviors in climate from unknown sources, is Mathturbation. I find that quite accurate. Fitting arbitrary periodic functions to the data shows really poor statistical agreement, and has roughly zero predictive power. Unlike considering the physics involved...
78561. ranyl at 01:26 AM on 27 July 2011
       Earth's Climate History: Implications for Tomorrow
       Worrying times unless we stop CO2 emissions. Peak 400pmm as a suggestion for safety? In figure 1 the early Pliocene (CO2 330-400ppm), is 2C hotter but I pressume it still had 20-25m higher seas, poles 19-21C hotter, warmer Eastern Pacific temperatures, wider tropical belt and generally different climatic zones when compared to the present as other researchers have reported. (Lunt D.J. et al, “Earth system sensitivity inferred from Pliocene modelling and data”, Nature Geoscience, VOL 3 , JANUARY 2010, Pagani M et al, “High Earth-system climate sensitivity determined from Pliocene carbon dioxide concentrations” Nature Geoscience VOL 3 , JANUARY 2010, Seki O. et al, “Alkenone and boron-based Pliocene pCO2 records” Earth Planet Sci Lett (2010), Schneider B. “Global warmth with little extra CO2”, Nature Geoscience, VOL 3, pg. 6-7, 2010, Csank, A.Z., et al., “Estimates of Arctic land surface temperatures during the early Pliocene from two novel proxies”, Earth Planet. Sci. Lett. (2011)) The Early Pliocene is most often reproted to be 3-5C hotter (ref. above) than pre-industrustial times making the 100yr climate sensitivity for a doubling of CO2 to be alot higher at 4.5-7.5C (70ppm is 0.4 of a halving if the initial CO2 is 350ppm, 70/(350/2)), whereas if 2C is correct then CS 3C is correct as above. Basically though over the long term 350ppm gets you to the Pliocene whatever its temperature was and you gets about 60% along the way in 100years (unless there is a significant hystersic effect in the way which seems unlikely as Greenland is likely to melt and Antarctica has been a stable albedo for much longer) and if it was only 2C hotter, 1.4C is 100 years looks a lot more relevant and we've already gone ~0.7C. Wonder how much effect an summer ice free arctic will have on the rate melt of Greenland? Ignoring the possibility of at least 2m sea levels rise by 2100 would seem poor planning to me.
78562. muoncounter at 01:21 AM on 27 July 2011
       CO2 is not a pollutant
       davidh#21: "gets even more problematic when you have to reconcile industrial emissions with natural emissions (e.g. "Am I polluting by breathing?")." That's just silly; we inhale much of the same CO2 we exhale. See the prior thread on breathing (use search). On the other hand, consumption of fossil fuels produces a waste product; on human time scales, it's a one-way process.
78563. Eric the Red at 00:56 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Sky, I am not sure exactly what you mean by steeper than linear, but assume that you are implying that the linear trend is increasing. That is simply not occurring, as the greatest increase in the past 40 years was observed in the 1990s, with the smallest occurring in the past decade.
78564. skywatcher at 00:31 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       #19, Tamino has a not very polite word for that kind of unsupported analysis, and has written about that kind of thing several times. I would describe it as climastrology, and not based on any mechanism or forcing factor. It fails miserably as you go further back in time, and has no predictive value. With enough degrees of freedom you can fit anything, but it does not mean you have found anything useful! There are good reasons to think the long-term trend is of different gradients at different times, as it follows from the sum of forcings, including CO2, aerosols and solar elements. On a shorter timescale, such as within an individual decade, forcings such the slight nudge from an individual solar cycle, or a series of El-Ninos transitioning into La Ninas over about a decade, will cause smaller wobbles in the larger trend. It happens that the past 40 years has an approximately linear trend. In fact it appears steeper-than-linear, as the temperature difference between the 2000s and the 1990s is larger than the temperature difference between the 1990s and 1980s, or 1980s and 1970s.
78565. Dikran Marsupial at 00:25 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric the Red however that does not mean that the observed temperature is the result of a periodic physical process. Computing a linear trend over a period where the changes in forcings have been fairly simple is a sensible thing to do. Curve fitting without taking into account what we do know about the underlying physics is pretty pointless. You comment "The data from ~1975-2005 falls on the increasing portion of the sine wave, and hence, appears linear." implicitly assumes that there actually is a sine wave in the data, rather than the observed temperatures being due to multiple changes in a range of different forcings.
78566. Eric the Red at 00:16 AM on 27 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       I agree that a single long-term trend does not reasonably characterize the data for the entire century. The data would best be described as a sine wave about a linear trend. The data from ~1975-2005 falls on the increasing portion of the sine wave, and hence, appears linear. Using Tamino's analysis on a sine wave superimposed upon a linear increase yields results wherein the bounds remain within the trend line for 130 years of data.
78567. Tom Curtis at 23:54 PM on 26 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric, the supposition you are making that there is one privileged long term trend to which the trend always returns is not warranted. You can generate a least squares linear trend for any set of data. It does not follow that it means anything. The data may be random, or quadratic, or logarithmic, or a succession of distinct trends. Consequently, the only thing you can conclude if the long term trend falls outside the 95% confidence interval of shorter trends in the series is that a single long term linear trend does not adequately characterize the data. If you then want to fit a linear trend plus long term cycle to the data, you can certainly attempt to do so, but no amount of analyses of graphs such as that in 13 will justify that attempt. As it happens, a single long term trend does reasonably characterize the data from 1975 to present, but it does not do so for the entire 20th century.
78568. Eric the Red at 23:33 PM on 26 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Tom, The former. The actual range would be determined by how far back the graph is extented. I suspect that if one were to go back to the late 19th century and start the trend at this time that there would be periods whereby the bounds fall above and below the trend line. The period you describe would be one of them. The short-term trends changed during these periods, but did not last, as it returned to the long term trend. The implication is that the long term trend is not static, but fluctuates above and below. Using Tamino's analysis, the fluctuations are not noise, but are real. Since the fluctuations occur about the long-term trend, and have always (so far) returned to the trend, there appears to be no reason to believe that it has changed recently.
78569. Bob Lacatena at 23:10 PM on 26 July 2011
       Are you a genuine skeptic or a climate denier?
       

       ...first that it confiscates the property of the fossil fuel investors.

       Cries of stealing profits or property from FF producers reminds me of asbestos. Would anyone argue that we should have let asbestos miners/manufacturers continue to ply their wares, despite the dangers... because it would be unfair to steal their property/profits from them? The Daily Show News article Really... what's the difference?
78570. Tom Curtis at 22:47 PM on 26 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric the Red @15, I am not sure what you are saying here. You may be considering an extension of Tamino's graph back to 1961, such that the longest trend and hence the red dotted line is drawn from the 1961-1911 trend. In that case, you claim (and I well believe) that at some point the bounds of statistical significance for some shorter term trends, presumably in the range 1975 to 1993 do not intersect the long term trend. That is an unsurprising result (if it is what you are claiming) and represents significant evidence that there has been a genuine (ie, long lasting) change in trend between 1961 and the present. Alternatively (and unlikely) you mean that the short term trends at the end of the figure fall outside the bounds of statistical significance for the long term (50 year) trend. Well, yes. They also fall outside those bounds for the 1975 trend. And that is entirely inconsequential, as it represents an incorrect use of the technique. In either event, I don't see any problem for the method of analysis.
78571. Eric the Red at 22:25 PM on 26 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Tom, Tamino's analysis works for the time period and trend indicated indicated. However, if one uses a longer term trend (50 years or more), then the bounds fall outside the trend line. I am not arguing that a change has occurred in the long term trend, but that shorter term trends fall above and below his bounds.
78572. Sarah at 22:23 PM on 26 July 2011
       OA not OK part 8: 170 to 1
       Doug, Correct. I'm was trying to simplify to the crux of Jeff's concern, which seems to be CT plus water. Additional contributions to alkalinity are critical for real world calculations, but the basic (and acidic!) chemistry ideas can be understood with a simplified mixture.
78573. Rob Painting at 21:41 PM on 26 July 2011
       China, From the Inside Out
       As if on cue here's a just published paper on sulfate emissions in China & India: Sulfur dioxide and primary carbonaceous aerosol emissions in China and India, 1996–2010 - Lu & Streets (2011) "From 1996 to 2000, emissions of all three species showed a decreasing trend (by 9 %–17 %) due to a slowdown in economic growth, a decline in coal use in non-power sectors, and the implementation of air pollution control measures. With the economic boom after 2000, 15 emissions from China changed dramatically. BC and OC emissions increased by 46 % and 33 % to 1.85 Tg and 4.03 Tg in 2010. SO2 emissions first increased by 61 % to 34.0 Tg in 2006, and then decreased by 9.2 % to 30.8 Tg in 2010 due to the wide application of flue-gas desulfurization (FGD) equipment in power plants." India's sulfate pollution on the other hand is still rising.
78574. bill4344 at 21:15 PM on 26 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Paul @#2

       Forbes is well know for its anti GW bias. Is it owned by Murdoch?

       No, it's owned by Bono.

       Roger McNamee, an Elevation partner who signed the deal last Friday, said Bono was drawn to Forbes because it "has a point of view"

78575. CBDunkerson at 20:48 PM on 26 July 2011
       CO2 is not a pollutant
       davidh, you are using a definition of "pollute" to dispute the accuracy of calling CO2 "pollution". They have the same root, but they are different words with different connotations. Look up the definitions of pollution or 'pollutant' in that "Macquarie Dictionary" you call authoritative and I guarantee you will find one which so describes anything which damages the environment. I doubt there is a single major dictionary, encyclopedia, or 'environmental protection' type law anywhere which does not define "pollution" in such a way that it would include CO2. Disagree? Cite a source.
78576. CBDunkerson at 20:28 PM on 26 July 2011
       Wakening the Kraken
       The biggest issue I see with 'mining' hydrates from the ocean floor is that it potentially moves the 'peak fossil fuels' point FAR down the road. If efficient means of extracting this methane are developed then we could be looking at continued use of fossil fuels for primary electricity generation AND transportation for centuries to come. Which would lead to extremely high atmospheric GHG levels and all the catastrophes that potentially entails... including the 'clathrate gun' possibility. Currently we have the 'advantage' of dwindling supplies of conventional fossil fuels. Even coal wouldn't last much beyond 2100 if we continued to use it as a primary source of energy. Yet with developments like the Canadians finding cost effective ways of extracting oil from tar sands, the Russians pulling methane out of permafrost, the Japanese going after methane hydrates, and so forth, that equation is changing. If it continues along this line our only hopes of containing greenhouse warming may be responsible political leadership (I won't hold my breath) or the cost of renewable power dropping significantly below fossil fuel costs.
78577. Tom Curtis at 17:54 PM on 26 July 2011
       CO2 is not a pollutant
       davidh @21, my view may be jaundiced from so commonly encountering on the web so many genuine deniers. However, I suspect that only genuine deniers will in fact be troubled by the word "pollution". This is because of the obviously specious argumentative company it keeps, such as, for instance the claim that CO2 obviously is not a pollutant because we exhale it. Of course, we excrete other things but are quick to call it pollution when it washes up on Manly Beach, and everybody knows it. That style of argument is an appeal to thoughtlessness - an attempt to divert attention from a serious issue by a glib meme which is superficially attractive but can stand no scrutiny. Of course there is the more robust argument that CO2 cannot be pollution because it is plant food and ... Oh that's right, we excrete plant food out the other end as well and are still very happy to call it pollution if it is dumped untreated into a river or sea. So not so robust after all. There is even the argument that we put CO2 into soft drinks, but you really do not want to go into the use of urea as a dietary supplement. The point is that the arguments commonly associated with the claim that CO2 is not a pollutant are all, and transparently specious. They would not be given serious consideration by any open minded person who actually thought about the issue. By not using the word pollution, we give those arguments rhetorical strength to substitute for their rational weakness. If instead of doing that, we challenge the claim that CO2 is not a pollution, we can easily show that it is, by standard, common place definitions. Of course the deniers won't accept that, but they were never going to be convinced anyway. But people with an open mind will accept it, and think worse of the deniers and denialism for having used such specious arguments in the first place. Having said that: 1) Actually I would be very surprised if more people used the "dictionary" definition then used the more practical definition enshrined in legislation. But of course, it may depend on which dictionary definition you use:

       "pollution The contamination of air, water, or soil by substances that are harmful to living organisms. Pollution can occur naturally, for example through volcanic eruptions, or as the result of human activities, such as the spilling of oil or disposal of industrial waste. Light from cities and towns at night that interferes with astronomical observations is known as light pollution. It can also disturb natural rhythms of growth in plants and other organisms. Continuous noise that is loud enough to be annoying or physically harmful is known as noise pollution. Heat from hot water that is discharged from a factory into a river or lake, where it can kill or endanger aquatic life, is known as thermal pollution. The American Heritage® Science Dictionary Copyright © 2005 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved."

       (My emphasis) If light and heat can be considered pollution, and no one misunderstands or disputes those descriptions, the CO2 certainly can be. 2) The assumption isn't that people will know or look at the legislative definitions. The assumption is that when they are pointed out, open minded people will recognize the objection to the use of the word "pollution" is specious.
78578. davidh5040 at 16:31 PM on 26 July 2011
       CO2 is not a pollutant
       Following up my post #18... (Firstly, let me make it clear that you don't need to convince me of the case for AGW and the likely risks we are facing because of it. My interest is in finding the best (least confronting and least confusing) way of communicating the issue to people who genuinely want to know, and who have to somehow wade through all the sound and fury out there to make a decision about what to believe.) muoncounter#19: I take your point, but still think it is a bit of a stretch. I think you are using waste in the sense of "anything left over or superfluous, as excess material, by-products, etc., not of use for the work in hand". This doesn't lead easily to "foul", "unclean", or "dirty". This gets even more problematic when you have to reconcile industrial emissions with natural emissions (e.g. "Am I polluting by breathing?"). Tom Curtis#20: Personally, I largely agree with your assessment of the commonly understood meaning of pollution. I have used the term carbon pollution myself, but have moved away from it myself because of the resistance that I have encountered (which I think has some justification). The places where I think your rebuttal needs to be strengthened are: 1) The assumption that everyone has the same (non-dictionary) understanding of "pollution". 2) The assumption that people will go to look at legislation (rather than a dictionary) when trying to resolve differences in opinion about the meaning of a word. Part of the problem might be that we are concerned about different audiences - I am mainly concerned with members of the general public that are trying to make sense of this stuff (rather than scientists, lawyers, or legislators). A secondary objection is that even if we accepted the legal definitions you propose, then I don't believe that carbon emissions fall under them (yet). Can you currently be prosecuted for polluting by emitting CO2? If not, I would have thought that CO2 emissions were (by definition) not pollution according to current law. I'm not a legal expert, so feel free to correct me if I'm wrong. With regard to accusation of being Orwellian: I understand where you are coming from, but I don't think the accusation is quite justified (it would be doubleplusungood if it was ;-). I wasn't trying to _insist_ that we not use the word. I was trying to suggest that there might be reasons to look for alternatives, or at least be clear about where our definition was coming from when we do use it. In summary, my own view is that while the use of the word pollution to refer to excess greenhouse gas emissions may become widely accepted in future, using this terminology at this point in time risks being counterproductive (depending on who you are talking to). But your mileage may vary…
78579. Doug Mackie at 16:26 PM on 26 July 2011
       OA not OK part 10: Is the ocean blowing bubbles?
       I am not sure what you are driving at. However, at just over 900 ppm, S (most as SO₄^2- is the 4th most abundant element in seawater (after Na⁺, Cl^-, and Mg²⁺).
78580. damorbel at 16:18 PM on 26 July 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #1108 Sphaerica, you wrote:- "Your obsession with semantics and word choice is crippling you." I don't think so. Science is not just about accurate measurement but also about clear explanation i.e. using words as precision tools to minimise misunderstanding. "The rest of us understand exactly what is meant by "diffusion," "transfer" and "flow" without the need to apply only certain terms to gases, solids or fluids..." I suggest "the rest of us" is not sufficient. I merely point to the text in a link given by Tom Curtis in #1105 which did not distinguish between 'diffusion' and 'flow', clearly not understanding Fourier's great theory. you wrote:- "as do the learned men who wrote the referenced papers and used those terms to begin with." The link was to a paper written by a historian. I do not regard historians as a reliable source, they do not generally use the scientific method.
       Moderator Response: [Dikran Marsupial] This line of discussion is off-topic. No more quibbling about terminology, damorbel has made his point, he knows what is meant by "flow of heat/energy" so there is no problem with communication, and so no reason to discuss this any further. This applies to everybody.
78581. scaddenp at 15:05 PM on 26 July 2011
       Are you a genuine skeptic or a climate denier?
       You know with all the calls by republicans for spending cuts in the budget before they will raise debt ceiling, you would think they would rush at killing US$39B of fossil fuel subsidies instead of a mere US$4B proposed. True free-marketeers do you think?
78582. jyyh at 14:55 PM on 26 July 2011
       OA not OK part 10: Is the ocean blowing bubbles?
       and I imagine if underwater volcanoes would be 100 times more active than they are sulfuric acid salts would show up much better in the measurements of ocean water (just channeling Plimer in the previous comment)
78583. Bibliovermis at 14:21 PM on 26 July 2011
       Other planets are warming
       Christine, This claim that scientists have placed their attention solely on a single variable is wholly incorrect. Please review this site and the primary sources that the articles link to, and consider that you may be doing exactly what you are condemning - finding lots of reasons to support a preconceived notion.
       Moderator Response: For example, Christine, see "CO2 is not the only driver of climate."
78584. ChristineSutherland at 13:54 PM on 26 July 2011
       Other planets are warming
       So, many different bodies may have quite different reasons for warming or cooling, and these may be irrespective of solar activity. No argument from me there, as long as climate change on planet Earth is given the same objective analysis and assessment. However scientists, being apparently quite anthropomorphically inclined, have placed their attention on a single variable, "human activity" and of course can then find lots of reasons to support their conclusions. The more likely scenario is that highly-complex and interacting variables are behind warming or cooling of all the bodies in our solar system, and since this occurs both with and without the impact of homo sapiens, we have to consider that our puny contribution may possibly be of no consequence, and that we ought to be continuing our search for understanding of climate change in other directions.
78585. Tom Curtis at 12:41 PM on 26 July 2011
       Milankovitch Cycles
       Glenn Tamblyn @34 with regard to symmetrical land mass in both hemispheres, you assume that ice sheets will advance at retreat at the same rate. However, you later point out that the albedo effect will increase much earlier in the transition than it will retreat. Therefore, given symmetric hemispheres, if an ice sheet forms in one hemisphere, a point will come when much of the other hemisphere's land mass is snow covered while the ice sheet still exists. The combined albedo should lock the globe into a glacial. Another minor point is that rock generally has a higher albedo than vegetation. The vegetation dissipates the energy differently in that about 10% of it is stored as chemical energy and then dissipated by the plant or animals later on, but the total energy absorbed by the surface is still greater.
78586. Tom Curtis at 12:25 PM on 26 July 2011
       CO2 is not a pollutant
       davidh @18, regardless of the dictionary definition, "pollution" is not used that way in common language. To take one example, I come from Mount Isa, whose copper ore has a high sulfur content. Consequently the emissions from the smelter had a high sulfur dioxide content, those emissions being traceable as far as the African coast. When the wind was in the right quarter, and weak enough, the sulfur dioxide would be carried into the town with the result that the sulfur dioxide formed into a weak acid when brought into contact with water, as in on the lining of the oesophagus and lungs. For many people that made breathing very difficult, and anything more than very light activity outside a significant health risk. If it rained, the acid was washed down onto plants, killing rose bushes across the town. What it did not do is make anything foul, unclean or dirty. I doubt that anyone would hesitate to call the SO2 pollution. Also from Mount Isa, lead has been periodically released into the environment by a variety of means. Soil containing the lead was indistinguishable from soil not containing the lead other than by chemical analysis. But again, when high levels of lead contamination was found at a local kindergarten, no letters (I am sure) where sent to the paper saying it was not lead pollution because it did not make the soil "foul or unclean, or dirty". One final example, also from the mines, in which ventilation was a major issue. One reason for that was to prevent the build up of carbon monoxide, which is famously a colourless, odourless gas, and hence by definition not foul, unclean or dirty. It also kills, so again I doubt anyone would hesitate to call it pollution. More fundamentally, the important definition in this case is not the Macquarie Dictionary definition, but the legal definition. So, whether you go with New South Wales and say an act of polluting is:

       "an offence of waste disposal if committed without lawful authority, wilfully or negligently, in a manner that harms or is likely to harm the environment (s. 5)"

       or with Victoria, and define it as:

       "where a person intentionally, recklessly, or negligently pollutes the environment or causes or permits an environmental hazard which results in: · a serious threat to the environment; · a serious threat to public health; · a substantial risk of serious damage to the environment; · a substantial risk of a serious threat to public health."

       CO2 is a pollutant. That it is a waste product can hardly be argued, and that it poses a significant threat to the survival of the Great Barrier Reef, and hence "a substantial risk of serious damage to the environment" is well established. The insistence that we not use perfectly accurate descriptive words because deniers don't like the connotations is Orwellian in a quite literal sense. It is an attempt to make thinking about the issue difficult by controlling the language used to do so.
78587. muoncounter at 12:23 PM on 26 July 2011
       CO2 is not a pollutant
       davidh#18: "connotations that don't really make sense in the case of CO2 as a greenhouse gase." You make an elegant argument; however, if you view CO2 as a waste product of fossil fuel consumption, the unregulated dumping of said waste into the open air would seem to fit your #1 definition of the verb 'pollute.'
78588. Glenn Tamblyn at 11:53 AM on 26 July 2011
       Milankovitch Cycles
       My understanding of the assymetry of the continents is that if they are symmetric, changes in insolation between NH and SH will cancel out in terms of any Albedo change - ice retreats in one hemisphere as it expands in the other so that the net Albedo change due to Milankovitch alone is much closer to zero. WRT early snow melt yes, that would occur during the early stage of the warming. But then the feedback available from albedo change would slow as the system waits for the ice sheets to recede. In contrast, increased snow range during the cooling phase is a factor that would cut in early but then not suffer a later lag since snow can just keep extending without needing ice sheets to form first. So Albedo change due to snow/ice is likely to be a stronger early driver during the cooling phase but more of a lagging driver during the warming phase. As for exposed rock & vegetation, the initial positive feedback is strong due to the rock being exposed. Later - perhaps 1000's of years, the albedo effect from this is somewhat reversed as vegetation replaces rock. Also at this point there is a negative feedback, opposing Oceanic CO2 outgassing as this new biomass soaks up CO2. Then during the cooling phase, it is unlikely to be the exact reverse. Snow extends, killing off vegetation but without an intermediate bare rock phase. Also, die back of all that dying vegetation is then a carbon source, opposing the uptake of CO2 by cooling oceans. So compare these patterns to the glacial cycles. Early warming - Milankovitch, CO2 (and perhaps Methane from melting permafrost) and early snow melt. Mid to late stage warming - ice retreat and exposed rock. Late stage warming, more ice retreat but diminishing impact as spherical geometry cuts in and slowdown of CO2 increase due to its logarithmic forcing and growth of vegetative biomass. Then early cooling - Milankovitch, more snow. Mid cooling -even more snow, spherical geometry startiong to make this more effective, cooling oceans so CO2 drawdown but also compensating CO2 release from dying vegetation. Late stage cooling - Biomass has returned to previous levels, CO2 drawdown increases so CO2 starts to become a more potent late stage driver. So simplistically, CO2 as larger early stage driver during warming with Albedo change cutting in more strongly at the end. And Albedo change is the stronger driver during early cooling with CO2 coming in more strongly at the end. And this matches the Ice Cores. During warming CO2 is closely coupled to temps. During cooling, particularly the 1st half, much less so. This would only be a general picture since there are a lot of other wrinkles - how and how fast ocean currents change for example. And no two glacial cycles from the cores are exactly the same. But within the limits of what we can quantify the ice cores certainly seem to behave substantially as we might expect.
78589. Philippe Chantreau at 11:50 AM on 26 July 2011
       2nd law of thermodynamics contradicts greenhouse theory
       I am aware of the pattern KR. To my knowledge, nobody has ever been banned from SkS. Damorbel's actions, so transparent and so consistent over time, have certainly earned him the right to set a precedent in the matter. However, considering how John has conducted this site so far, I doubt that he will do that; yet we will continue to endure the whining of pseudo-skeptics about being silenced when nonsense is called out. In thermodynamics, by respect to energy and entropy, we "can't win." It seems to be like that too in the parody of debate maintained by pseudo-skeptics.
       Response:

       [DB] In the spirit of transparency, a select few have "crossed the line".  Damorbel may yet indeed set a precedent; that remains to be seen.  As an alternative, I earlier proposed "Damorbel's Law", for those who wish to consider it.

78590. Keith Hunter at 11:27 AM on 26 July 2011
       OA not OK part 10: Is the ocean blowing bubbles?
       I can't resist adding that if ocean outgassing were the source of the rise in atmospheric CO2, then the pH of the surface ocean would be increasing. It's not, it's decreasing, as shown by several time series.
78591. davidh5040 at 11:25 AM on 26 July 2011
       CO2 is not a pollutant
       I'm going to talk about semantics for a moment, so if you are only interested in the science, then skip over this… I think it is important to understand why someone might object to the term pollutant. The argument might go like this: 1) I am more likely to rely on a dictionary to get my definitions, rather than US legislation or the Encyclopedia Britannica. 2) I am in Australia, so I would usually refer to the Macquarie Dictionary as the authoritative source. Their definition for pollute is: 1. to make foul or unclean; dirty. 2. to make morally unclean; defile. 3. to render ceremonially impure; desecrate. 3) These senses of the word have connotations that don't really make sense in the case of CO2 as a greenhouse gase. 4) Thus the use of the word pollutant could appear to be imprecise and/or an attempt to use the fallacy of "loaded language" in order to persuade. For many, this might seem like hairsplitting to distract from more substantive issues. However, I object when I see contrarians using language that I consider imprecise or loaded, so I think it fair to listen when they make the same charge. I'd suggest that if we can make the case without describing CO2 as a pollutant, then it is probably worth doing so (both as a courtesy, and also to avoid getting diverted into a semantic debate). If we do use the word pollutant, then we should preface this by an explanation of where our definition is coming from.
78592. scaddenp at 09:47 AM on 26 July 2011
       Wakening the Kraken
       The important point I think though is comparison with clathrate gun hypothesis. This assumes that ocean warming takes hydrates out of stable phase, which further warms ocean, which then destabilizes more hydrate etc. By comparison, mining proposal I have seen involve hydrates in cold ocean sediment, nowhere near being destabilized, and being mined by hot water injection with some trapping device (and the trick is in the trapping device). What I cant see is a mechanism by which this process could become self-sustaining without the hot water injection.
78593. John Hartz at 09:31 AM on 26 July 2011
       Rising Oceans - Too Late to Turn the Tide?
       This article is a repost of a Univ. of Arizona news release about the paper: "The role of ocean thermal expansion in Last Interglacial sea level rise", Nicholas P. McKay, Jonathan T. Overpeck,and Bette L. Otto‐Bliesner Received 25 May 2011; revised 7 June 2011; accepted 9 June 2011; published 21 July 2011. GEOPHYSICAL RESEARCH LETTERS, VOL. 38, L14605, doi:10.1029/2011GL048280, 2011
78594. Tom Curtis at 09:09 AM on 26 July 2011
       China, From the Inside Out
       Agnostic @89, my assumptions are: 1) Global warming needs to be limited to a 2 degree C increase to have a reasonable chance to avoid catastrophic consequences of global warming. That is science based (PDF). 2) Total CO2e emissions to 2050 need to be limited to 1000 Gigatonnes of CO2e to have a reasonable (75%) chance of avoiding a greater than 2 degrees C increase in global temperatures. That is certainly science based. 3) A limit on total emissions makes the right to emit a scarce good within the technical meaning of the term of economics, and hence such a right has an economic value. That is not a science based assumption. Rather, it is one of the fundamental assumptions of economics, which I can presume to be a reasonably objective discipline. If you wish to reject all of modern economic theory, as you would have to to reject this assumption, please let us know. 4) Given an economic value of a good, you can make a preference ranking of any free assignment of those goods based on the quantity assigned to each person. If an unequal assignment is considered preferable, that represents a greater preference for the well being of the person or persons receiving the greater quantity of goods, with the level of preference being given by the quantity of goods assigned/ the average value of goods assigned across the population. (4) follows straight forwardly from decision theory. It has, however, been widely rejected by some people. In particular, Marxists have rejected the notion, instead maintaining a principle of "From each according to his ability, to each according to their need." Adherents to the free market, on the other hand, recognize that some people have greater need for certain goods, and that utility will be maximized of an assignment based on need is achieved. However, they maintain that the utility maximizing assignment is best achieved by free exchange. In that case, an unequal initial assignment will always be reflected in unequal final utility after exchanges have taken place, and hence represent a differential valuation of individuals if the initial assignment is deliberately chosen as a matter of policy. Hence (4) follows straight forwardly from decision theory and adherence to the free market. Again, if you would rather accept Marxism, please let us know. So, while my "assumptions" are not exclusively based on science, they are based science, two soundly based formal disciplines, and a foundational assumption of western societies (however inconsistently applied by many). I don't know what your assumptions are based on, but their consequences are to value citizens of the West, and in particular of the US more highly than citizens of other nations, and in particular of the third world. I have seen many argue that such a valuation should be the approach of any national government. I disagree, but I doubt that is relevant. What is relevant is that you cannot rationally expect the Chinese government to value US citizens more highly than its own; and therefore cannot rationally expect them to accept an agreement that effectively does so. Therefore negotiating on a basis that implicitly does exactly that is to doom the negotiation to failure. Consequently the choice for rational governments is simple. If you want to solve the global warming crisis through international agreement (and it is difficult to see any other means), then the basis of negotiations must be on equal per capita emissions rights. For practical purposes, those rights must be tradable.
78595. Tom Curtis at 08:13 AM on 26 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Eric the Red @7, and following, the correct way to compare recent short trends to the long term trend is to use the procedure Tamino illustrates here with GISS data: The solid line is the trend from the given year to the present (June 2011). The two dashed lines show the bounds of statistical significance (95% confidence). If neither bound crosses the long term trend line (red dashed), speculation about a change in the long term trend is just that, speculation, and is not based on substantive evidence.
78596. Tom Curtis at 08:04 AM on 26 July 2011
       Wakening the Kraken
       scaddenp @43, if the clathrates are mined without leakage, there impact on the global warming will be in the form of emitted CO2, and hence much smaller than for the clathrate gun hypothesis. But you have to wonder how the leakage rate will be kept small, and how that would even be measured if their is significant leakage in the mining process. And even in the event that leakage is curtailed, it is likely that this is an energy intensive means to get natural gas. That means the whole fuel cycle CO2 release per ton of methane from clathrates will likely be higher than that from conventional gas fields. So I believe concern is appropriate. On the other hand, for mining clathrates to be as bad as the spontaneous release of clathrates, near 100% leakage would need to apply, making the venture commercially unviable.
78597. Eric the Red at 07:56 AM on 26 July 2011
       Michaels Mischief #1: Continued Warming and Aerosols
       Dave and Kevin, I think we are in agreement about the long term trend. There are periods of higher trends, lower trends, and flatness. However, long term, the trend has not deviated significantly. When you compare the most recent years, you will see that they do not deviate. My point earlier, was than if there was a deviation, then it should be evident when compared to the long term trend.
78598. scaddenp at 07:24 AM on 26 July 2011
       Wakening the Kraken
       Okay, so I am in the industry and may be biased but I think the risks here are somewhat overstated. In terms of GHE, its same as natural gas. While much is made of the narrow stability zone for hydrates, how do you propose that the instability zone is propogated from where the hydrates are mined (and trapped) to area where methane would be released and how would such a process be sustained?
78599. scaddenp at 07:10 AM on 26 July 2011
       Milankovitch Cycles
       "bare rock is slowly converted to soil and biomass." This is a negative feedback (removing carbon), but the vegetative changes have a more direct effect of decreasing albedo especially with forest expanding into tundra, which is a quite rapid change in this context. And of course this change is much more pronounced in the NH cf to the south.
78600. Riduna at 07:10 AM on 26 July 2011
       China, From the Inside Out
       Tom Curtis @ 88 Your assumptions are entirely wrong and hardly science based. Thank you for your views.

Prev  1564  1565  1566  1567  1568  1569  1570  1571  1572  1573  1574  1575  1576  1577  1578  1579  Next