Arguments
Recent Comments
Prev 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 Next
Comments 104451 to 104500:
-
Tom Dayton at 06:31 AM on 17 November 2010The 2nd law of thermodynamics and the greenhouse effect
Michele, a similar argument about wave interference was made by another commenter a while ago on another thread. I posted links to explanations and animations that help illustrate the responses by muoncounter and KR. See these comments on that other thread: 206, 207, and 208. See also Riccardo's comment there. -
Daniel Bailey at 06:09 AM on 17 November 2010Are ice sheet losses overestimated?
Re: "The Inconvenient Skeptic" (16)"The paleoclimate data does not show long periods of stability, even in the Holocene period and the Holocene is unusual in the duration of the stability. There is still plenty of evidence that the sea levels were 2-3 m higher in the past few thousand years. (Rohling)"
Your claim about the Holocene not being stable is countered by this:
Your claim that your linked Rohling source shows sea levels 2-3 meters higher in the past few thousand years is countered by your linked source, wherein this statement is found: "The first two arrays in the attached spreadsheet concern all the compiled raw data. The latter two arrays concern a simple smoothing (3-pt moving average), to reduce sample-to-sample noise. The 1 sigma interval around this 3-pt moving average smoothing is +/- 6.5 m (see Rohling et al., 2009 Nat. Geosci.)."
How you deduce 2-3 meter higher sea levels from a dataset with +/- 6.5 m accuracy and at best a 500-year resolution is beyond me. Did you not even look at it?"It is probable that there were many periods in the past few thousand years that Greenland was losing mass at a greater rate than it is now. Even if the MWP was isolated to Greenland, it would have been losing more ice then."
Any source for this claim? Conflations with regional/localized events like the MWP belong on a different thread. Please use the search engine in the UL corner of every SkS page to search for a more appropriate thread. Frankly, little in your comment indicates genuine skepticism or acts as a positive contribution to the discussion on this thread. The Yooper -
Tom Dayton at 06:00 AM on 17 November 2010How significance tests are misused in climate science
BP, I second KR's comment. Relevant also are my responses to Eric (skeptic)'s claim that science has no place for probabilities of the the correctness of theories other than 100% certainty, on the thread The Science Isn't Settled. Start with my most recent comment and work backward by clicking the embedded links to the previous comments. -
The 2nd law of thermodynamics and the greenhouse effect
Michele - I've seen this constructive/destructive interference argument before. However, this kind of interference does not destroy any energy, merely displaces it at most a half-wavelength of the beat frequency. And it only occurs with coherent light and the boundary conditions muoncounter pointed out, neither of which applies in atmospheric IR. Constructive/destructive interference is a red herring. It's simply not relevant to Earth climate energies. -
It's the ocean
h-j-m - Do you perhaps have any evidence that one of your alternative theories is true? You've put forward three different hypotheses, without numbers or supporting evidence - as opposed to the article this thread is based upon. And to quote Christopher Hitchens, assertions without evidence can be dismissed without evidence. As to warmer water leading to evaporation and more warming, well, that's absolutely true, one of the basic positive feedbacks to temperature change. That's well understood basic physics, and doesn't lead to a runaway situation, if that's what you're implying. -
muoncounter at 05:33 AM on 17 November 2010The 2nd law of thermodynamics and the greenhouse effect
#121: "The sum of two counter - propagating waves (of equal amplitude and frequency) creates a standing wave" That's true when there are requisite boundary conditions (such as a pair of reflecting or nonreflecting surfaces). If this is the atmosphere, what boundary conditions are you suggesting? -
Michele at 05:29 AM on 17 November 2010The 2nd law of thermodynamics and the greenhouse effect
I would remind something about what occurs when two waves traveling in opposite direction interfere between each other, taking into account the simplest case 1-D. 1- The sum of two counter - propagating waves (of equal amplitude and frequency) creates a standing wave and there isn’t propagation of energy. In other words, using the principle of superposition, the resulting wave may be written as: R = Asin(kx+wt) + Asin(kx-wt) = 2Asin(kx)cos(wt) that is no longer a travelling wave because the position and time dependence have been separated. 2 – If the two waves haven’t equal amplitude, then the global effect is: R = (A + B)sin(kx+wt) + Asin(kx-wt) = 2Asin(kx)cos(wt) + Bsin(kx+wt) that corresponds to a standing wave 2Asin(kx)cos(wt) plus a traveling wave Bsin(kx+wt) which has the propagating sense of (A+B). In other words, the strong wave (A+B) blocks on the way the weak wave (A) and there rests acting only the difference between the two waves. That’s, the traveling effect of counter wave Asin(kx-wt) (for us, the back radiation) vanishes on the way and there’s a reduced traveling effect of stronger wave (A+B). Of course, the energy that don’t travels isn’t destroyed but simply turned into potential energy of the stationary wave. There is nothing strange. In all phenomena of nature only the strongest survive and it always stifles the weaker, that however isn’t suppressed but only captured because Nature always selects for to operate the most elegant and economic way. -
h-j-m at 05:25 AM on 17 November 2010It's the ocean
Claims that the warming of the planet is due to heat being released from the oceans into the atmosphere are not supported by any empirical evidence or peer-reviewed science. Thus ends the article. But if I am not mistaken the temperature of the water is one of the dominant factors determining the rate of evaporation (i. e. the warmer the water the higher the rate of evaporation). But more evaporation equates to more water vapour in the atmosphere (aka latent heat) which will result in warming the atmosphere. Else a lot of physics text books need rewriting. In a previous post I complained about mentioning alternative explanations for rising ocean temperatures. I will give just three with the humble request to be shown how or where these are debunked. 1. Marine as any other life needs energy to build its biomass. By now we are next to successful clearing our oceans of it. In consequence that energy is not used for this purpose and heats the water instead. 2. There may be spots where the earth crust has grown thinner over time and therefore more of the earth's interior heat gets transferred to upper layers. As the earth's crust is thinnest below oceans this may heat the water above. 3. Not only are we clearing out next to all marine life from the oceans we are using them as garbage bins as well. I recall reports stating that all over the oceans probes were taken that revealed a higher content of plastics than phytoplankton. I think it is rather likely that these areas when hit by visible light will absorb more of it and in return emit more infrared radiation aka heat. -
The Inconvenient Skeptic at 05:21 AM on 17 November 2010Are ice sheet losses overestimated?
Ok, lets flip this around a little bit. What should the ice loss be? Was the ice loss greater in the late 1940's? What would the ice loss be if there had never been an increase in CO2 emissions? The paleoclimate data does not show long periods of stability, even in the Holocene period and the Holocene is unusual in the duration of the stability. There is still plenty of evidence that the sea levels were 2-3 m higher in the past few thousand years. (Rohling) It is probable that there were many periods in the past few thousand years that Greenland was losing mass at a greater rate than it is now. Even if the MWP was isolated to Greenland, it would have been losing more ice then. Nothing I have seen indicates multi-century stability in glaciers, sea level or temperature. That mankind now has the ability to monitor the tiny changes does not mean that increased CO2 is causing them. John Kehr The Inconvenient Skeptic -
How significance tests are misused in climate science
Berényi - Two comments. (1) You state that weather is in a state of Self Organized Criticality - SOC. I have been unable to find any references that indicate this; do you have a paper to link to on this subject? A statistical analysis of unforced noise in the climate? While water vapor, ice, and condensation are critical point transitions, weather doesn't seem to display the same behavior as a whole. In particular, a pink noise 1/f relationship would indicate the largest variations on low frequencies, where what we observe (glacial cycles, for example) is a fairly direct tracking of climate variables (temperature, ice cover, etc.) to historic forcings. (2) The universe is what it is - that's the final arbitrator of our theories. However, our knowledge is imperfect, and our hypotheses are probablistic, as per the first definition of probability. We can only state that a particular hypothesis is more probable than others given the evidence, the statistics of our data. And whether using Bayesian or frequentist methods, we can estimate from the statistics the probability (second definition) that our hypotheis is supported by that data. That's how induction works, and how we can learn something new. We can be pretty sure, but we can only work with the evidence we have - we don't have perfect knowledge of anything. At a certain point we become certain enough to label a particular hypothesis a fact. Gravity, evolution, and it appears climate change falls into that category as well. But even the strongest "fact" is supported by our inductive conclusion that the laws of physics are consistent over space and time, and won't change on us - incredibly well supported, but the rules could change tomorrow. Crystalline proofs of the type you describe would be nice, but they don't exist. -
muoncounter at 04:51 AM on 17 November 2010A detailed look at galactic cosmic rays
#23: The Harrison and Ambaum 2009 paper you cite is about earth's electric field; it has nothing to do with this topic. The words 'cosmic ray' appear in the abstract, keywords and a non-specific reference to a 1989 paper. The statement in the abstract ... arising from the combination of distant thunderstorms, Earth’s conducting surface, a charged ionosphere and cosmic ray ionization is utterly inconclusive. Neither 'GCR' or 'galactic' appears at all. -
Dikran Marsupial at 04:45 AM on 17 November 2010How significance tests are misused in climate science
Maarten Ambaum @ 46 wrote "Also a frequentist would agree with the statement that the p-value does not contain enough information to calculate the probability of the truth of a hypothesis, or the null hypothesis (such statements can be perfectly well framed in frequentist terms)." The first part is certainly true, however the second is not; the frequentist framework does not allow probabilistic statements to be made concerning particular hypotheses. Frequentist statistics can assign probabilities to the ocurrence of errors in repeated application of statistical tests, but that is not the same thing (I checked this with my vastly experienced frequentist colleague and he concurs). If it were true, frequentists could construct a credible interval, rather than a confidence interval by considering the hypothesis that the true value of a statistic lying within a particular interval. But as far as I know, frequentists cannot construct a credible interval - however I'd be very interested to hear otherwise. -
muoncounter at 04:40 AM on 17 November 2010Ice-Free Arctic
#75: "distinguish between BC absorption in the atmosphere and on the ice surface." I'm suggesting that the presence of BC in the Arctic, traced to sources in Europe and Asia, is the key; not where the BC winds up once it is in the Arctic. With BC comes CO, CH4 and CO2 from fossil fuel and biomass burnings. The relative weight of melting due to GHG-induced warming vs. surface BC-induced heat retention isn't the question. -
Karamanski at 04:29 AM on 17 November 2010CO2 limits will harm the economy
Would Cap-and-trade be an effectual way of significantly reducing greenhouse gase emissions? Or do we need a much more aggressive bill to make large differences in greenhouse gas emmisions -
h-j-m at 04:25 AM on 17 November 2010Animals and plants can adapt
The article starts quite factual with stating that biodiversity is under constant thread from direct human interference, Most prominently by destroying (slowly but surely) land for industrial use (food industry) with the latest addition of biological fuels as well as destroying the oceans by depleting them of marine live and using them as trash bins at the same time. In my opinion that needs to be stopped and as far as possible reversed. Reducing CO2 emissions (unless they stem from deforestation) will not help a bit. Besides, if I am not mistaken it is still the tropical rain forests that boast the richest biodiversity which happen to occur where this world counts the highest temperatures. Therefore I completely fail to see how rising temperatures may cause general losses in biodiversity. -
Stephen Baines at 04:20 AM on 17 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
I wanted to add that in this interview Oreskes is really pithy and bang-on. Clearly she has benefitted from practice honing her responses over time. Soon after the book was published her interviews tended to be a bit more rambling -- now she is sharp as a tack. -
Daniel Bailey at 04:15 AM on 17 November 2010Are ice sheet losses overestimated?
Re: Chris G (12) GRACE measures its altitude above the surface to then deduce mass lost or gained. Isostatic rebound can introduce error into the calculations, so proper adjustments for rebounding of the basement rocks as the ice overburden is removed must be made. There is no "replacement of mass" by the mantle in the mass-portion of the calculations per se...but the rebound adjustment must be done properly for the correct altimetry data to be obtained that can THEN be used in the mass lost/gained calculations. Hope that's more clear. The Yooper -
Chris G at 04:04 AM on 17 November 2010Are ice sheet losses overestimated?
Agnostic (#8), IDK, but IMHO... Rising sea levels will result in property loss and in some areas mass migrations, and this will take place over many decades to centuries. In contrast, shifts in temperature and rainfall patterns, and ocean acidification will affect, and almost certainly in a negative way, where, and how much, food can be grown. The latter changes are taking place now and can change in just a few decades, or even less if a tipping point is reached; personally, I see the latter as a larger threat. I should probably defer any follow-up to the topic of climate change costs. -
Stephen Baines at 04:01 AM on 17 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
@ John Harrington #32 Some personal perspective... There is an old truism that holds that academic debates can get as vitriolic as they do precisely because there is so LITTLE at stake. I can imagine that in certain corners of certain fields there can be a bit of bullying primarily because the outcome concerns very few people and bullying pays. The same scenario is possible in any walk of life with similar paramters(although it doesn't really occur often if you think about it). That said, in my 25 years in science I have never seen anything on the scale you describe. I have certainly seen personal biases and conflicting personalities play a role in scientific exchanges (some much more unjustifiably aggressive than evident in those darn climategate emails) - but in the end it is the intellectual/empirical side that eventually holds the field in those exchanges. That's what matters. That result is possible because in my science, as in climate science, it is impossible for one person to gain much control over opinion precisely because there are a reasonable number of peers working in the field. Scientists hate despots more than most people -- scientists are usually fierce individualists, and the abuse of power conflicts with the free flow of scientific ideas. I also know that if I work on a problem or an approach that is outside the mainstream, I have to work a bit harder to gain acceptance. I don't complain about it -- that is as it should be given that scientists should be critical. But, in the few times I have followed that less trodden path in the past, I have never once felt that I have been blackballed or censored for my positions. Not once. It is very hard to get any consensus in science on anything without overwhelming evidence in one direction or the other. Those who claim that there is some conspiracy among scientists regarding AGW (by which I mean CO2 effects on climate) have no clue how the process works or how fiercely independent scientists are in general (or they depend on others not knowing). -
Chris G at 03:47 AM on 17 November 2010Are ice sheet losses overestimated?
Oh, maybe it is the case that previous studies have larger estimates for isostatic rebound than Wu, et al, 2010. -
Chris G at 03:41 AM on 17 November 2010Are ice sheet losses overestimated?
I'm having a problem at the conceptual level with all this; maybe someone can help. Let's say you assume no isostatic rebound and you measure a certain loss of ice mass, I, using GRACE. Under this assumption, Total loss = I. If the mantle is rebounding, some of the ice mass lost is being replaced by mantle mass; let's call the mantle mass M. Under this assumption, T = I - M. That is, the total measured mass loss is whatever is lost in ice, minus whatever has been replaced by rock. If the mantle mass rebounded perfectly with the ice mass lost, there would be zero measured mass lost. Changing the formula around trivially, you can say, I = T+M. The data regarding mass loss from GRACE (T) hasn't changed; so, I don't yet understand how introducing a rebound effect can reduce the estimate of how much ice has been lost. -
michael sweet at 03:13 AM on 17 November 2010How significance tests are misused in climate science
In Schmidt and Manns response to Mcshane and Wyner, Schmidt and Mann calculate a 99% probability of the last decade being the warmest in the record using the Lasso stastical technique from MW. They then discount that probability to likely (66-90%) claiming unidentified measurement uncertainty and possible systematic errors (page 3). When they discount their statistics that much, does the difference between Bayesian and Frequentist really amount to anything? If climate scientists use frequentist statistics and then discount the result to account for unknown errors they will still have conservative estimates of the actual effects. -
JohnHarrington at 03:12 AM on 17 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
@David Horton, I had meant to make clear, but apparently didn't, that the conversation happened in the course of discussing global warming. No, I certainly don't intend to imply that that's what is happening with global warming science. That was her implication, not mine. I'm not a denialist of any kind. I accept the science, and always have. I came here because, as I said, I wanted to hear from practicing scientists who could offer their experience to counter the claims of my scientist-manque acquaintance. I wanted this because a friend was present who was taken in by her description of "modern science" and I'd like to offer him another perspective. -
Berényi Péter at 01:59 AM on 17 November 2010How significance tests are misused in climate science
Maarten, statistics is never used in natural sciences in a way you put it. That is, it simply does not make sense to talk about the probability of hypotheses being true (or false). It's either true or false. Of course it is entirely possible we are ignorant about its truth value; in that case one should say I do not know (a perfectly legitimate scientific stance), but it surely has a truth value, even if no one was able to determine it so far (provided of course the hypothesis makes sense in the first place). The Bayesian method you describe could only serve as a heuristic device, but only if we had clear (quantifiable!) picture of prior probabilities regarding our own ignorance. That's almost never the case. If we knew how ignorant we were (having a reliable structural model of our own ignorance), most of the job required to overcome this ignorance would already be completed. However, when heuristics is most needed, we are at the edge of utter darkness, just feeling our way around, not even equipped to make educated guesses about Bayesian priors of our own state of mind regarding the subject matter. In cases like that almost any fractional understanding is better than fake formal methods to arrive at a reasonable conclusion regarding the way forward. It may be different for decision makers (like politicians or business people) who rely on expert advice in certain matters, but are not equipped to actually understand and evaluate the detailed reasoning behind those expert opinions (they only digest the executive summary, anyway). They may well wonder how likely it is the experts have got it right, and in complicated cases it makes perfect sense for them to seek a quantified description of uncertainty. To ask an independent group of experts to give an estimate of prior probabilities and build a Bayesian model to evaluate reliability of expert propositions may be a way forward. However, in practice extra rounds like that are seldom better than honest expert meta-opinion, expressed in plain language. There is a more restricted domain where statistics can (and do) come into play in natural sciences. That's measurement laden with noise. However, in this case there is no room for theoretical ambiguity. We should know pretty much everything how the signal we are looking for is supposed to look like along with the statistical properties of noise behind which it is hiding. This knowledge should take the form of a bunch of true propositions about the phenomenon under scrutiny, neither of which has a dubious truth value expressible in a probabilistic form. If this knowledge is given, we should be able to build an adequate statistical model which enables us to recover the signal from noise as much as possible. Of course the first thing to do is not to rely on statistical speculations, but to improve the signal to noise ratio of measurement whenever it is practicable. Unfortunately in climate studies most of the noise is not from the measurement procedure itself, but it is weather noise, that is, an inherent property of the system itself. There is no way to get rid of it during the measurement phase. Weather is an open thermodynamic system, and as such it works on the edge of chaos, in other words it is always in critical state (by way of SOC - Self Organized Criticality). Systems like this are characterized by system variables with pink noise characteristics (the noise has random phase and the same power in each octave). Pink noise is scale invariant with no lower cutoff frequency, therefore system variables like this do not make a natural distinction between weather and climate, no matter how long is the averaging window used (how low the upper cutoff). Pink noise is never stationary, it has an arbitrarily long autocorrelation scale. This is why it is a bit tricky to look for trend (as signal) in a climate variable laden with weather noise. A simple model of a linear trend plus some stationary noise would surely not do (even if mainstream climate science is almost always guilty of using such simplistic models). Pink noise can have spontaneous excursions on all scales, including extremely low frequency ones (well in the supposed climate range of 30+ years). You say "A standard answer [to the question if temperatures are rising or not] is to calculate a temperature trend from data and then ask whether this temperature trend is “significantly” upward; many scientists would then use a so-called significance test to answer this question. But it turns out that this is precisely the wrong thing to do." Yes, but it is not wrong just because the result of an otherwise correctly applied significance test is misused, but in most cases people also apply the wrong significance test (that fails to take into account the very long autocorrelation timescale). The above statements on weather (or climate) noise, critical state, self-organized criticality, pink noise, etc. are simply true statements with no further qualification whatsoever. It is not likely they are true, not even 100% sure, they are simply adequate descriptions of certain aspects of the behavior of open thermodynamic systems with many degrees of freedom. Still, they are entirely missing from IPCC reports, prepared by experts for decision makers. Phrases like "pink noise" (or "1/f noise") are not even mentioned under http://ipcc.ch. Funny. -
HumanityRules at 01:51 AM on 17 November 2010A detailed look at galactic cosmic rays
On the issue of GCR Cloud Seeding You seem to have completely ignored the body of work by Harrison and others who have made in situ cloud observations which "are consistent with enhanced production of large cloud droplets from charging at layer cloud edges." There's an example of their work below but also many more from what I can see in literature searches. Harrison and Maarten 2009 -
Ann at 01:48 AM on 17 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
@John Harrington #32 (BTW I am not a practicing scientist, I am an engineer and speaking from my point of view) In view of all technological progress made in the last centuries, I would say in general the scientific process seems to work pretty well. If we only look back 100 years, we can see how much our world has changed thanks to the new insights developed by the scientific community. This is not so much due to individual scientists – although of course talented scientists can have a big impact – but it is mainly due to the scientific process, that validates, connects and consolidates knowledge. Many things we take for granted nowadays wouldn’t be around without this scientific process. For instance: cars, airplanes, spaceships, television, cell phones, computers, robots, all sorts of electronics, medicines, operating equipment, power plants, … Non-scientists generally don’t have a clue as to what tremendous combined effort in various disciplines has been necessary to develop these products. I am thinking of materials science, crystallography, astronomy, mechanics, electronics, information theory, electromagnetism, quantum mechanics, thermodynamics, chemistry, biochemistry, chaos theory, etc. If it were true that "science is about dominant factions of science bullying those who disagree" you would never see this kind of progress. Actually, you would see no progress at all. I rest my case. -
HumanityRules at 01:32 AM on 17 November 2010How significance tests are misused in climate science
Thanks for the insights Maarten. I searched your work on Web of Science. It looks like you'd have heaps to contribute if you felt so inclined. The cloud ionisation work with Harrison caught my eye. The most recent article on SkepticalScience about GCRs seems to have neglected the insights from Harrison's work. (Apologies for going OT) -
robert way at 00:27 AM on 17 November 2010Are ice sheet losses overestimated?
Cryosat-2 *should* be able to help very much although it will still have its downfalls like the other methods. Ultimately what you will see is that Cryosat-2 data will be probably the most important dataset in the future for ice sheet change detection. That being said, I could never see radar interferometry not being useful as it is the only method that can actually detect and measure when flow increases from outlet glaciers. The problem with radar interferometry though is that you can measure the outputs, but knowing the thickness of glaciers and how much snow comes in, is more difficult. All in all, cryosat-2 is going to be a great tool but there will probably be hiccups initially. -
Daniel Bailey at 00:26 AM on 17 November 2010Are ice sheet losses overestimated?
Re: oamoe (9) Yes. Cryosat-2's primary mission:"ESA’s Earth Explorer CryoSat mission, launched on 8 April 2010, is dedicated to precise monitoring of the changes in the thickness of marine ice floating in the polar oceans and variations in the thickness of the vast ice sheets that overlie Greenland and Antarctica."
The calibration phase should be complete and full-service data collection begun. The Yooper -
oamoe at 00:01 AM on 17 November 2010Are ice sheet losses overestimated?
Will Cryosat be able to clarify this situation? -
TimTheToolMan at 23:18 PM on 16 November 2010Climate cherry pickers: cooling oceans
"What we do know, and have measured, are not absolute TSI's and forcings, but rather time-resolved points of deltas in forcings; when they have changed to some extent." Even our knowledge of TSI has been based on significant and invalid assumption. Haigh et al. using the new SIM data show that where we thought a decrease in "TSI" should mean decreased radiation reaching the surface, the makeup of the TSI matters and is non-intuitive and not previously measured. This new knowledge could have significant ramifications to climate science. -
Ken Lambert at 23:18 PM on 16 November 2010Climate cherry pickers: cooling oceans
KR #35 & kdkd #36 Had a look at the ACRIM and PMOD satellite TSI series. It is a somewhat confused picture with ACRIM Composite being written up as the best of the ACRIM 1,2,3 satellite reconstructions compared with PMOD which is somehow model based. Even then ACRIM produced a positive trend over the last 30 years equal to about +0.1W/sq.m (0.04%)solar radiation at the surface, whereas PMOD seems a negative or no trend. My main point was that none of these reconstruction uses SORCE TIMS or can explain the -4.5W/sq.m absolute difference in TSI. In fact the SORCE people produced their own Earth's energy flux balance chart (a la Dr Trenberth's famous chart) based on a TSI of 1361.5 W/sq.m rather than 1366 W/sq.m. Apparently it was crap according to a leading climate scientist. Your point about differences and deltas being the important determinant of trends is correct, provided we know what is happening at start time T1 with the particular forcing we are examining. Overriding this is BP's point that when you look at the satellite TOA imbalance data for the 2002-04 period there is no significant delta at all, see here: http://www.skepticalscience.com/news.php?p=2&t=107&&n=178#12580 when OHC content charts quoted above show a big leap. That is why high precision (month-month or year-year with same instrument) but low accuracy satellite data must be looked on as much more reliable than transitional XBT-Argo data measuring OHC. kdkd makes an interesting point. Clearly we have to try and pick winners here. Sort which data is crap and which might be close to correct. When there is conflicting data - the method is to look at its nature and try to find logical reasons why one might be good enough to be useful and the other not so. Satellite deltas verses XBT to Argo transition is a no brainer I would have thought. -
mbayer at 23:01 PM on 16 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
The message of the book is that these people that do things for their (weird) ideological reasons. These people are good enough for the special interests. In fact, any denier voice is good enough for the special interests. The special interests are not in for the science. They just want to keep polluting and getting away with it. -
kdkd at 22:32 PM on 16 November 2010Climate cherry pickers: cooling oceans
KL #34 You can't have your cake and eat it you know. Making (correct) claims that particular measurements are too imprecise to be terribly useful is one thing. Following on from that your argument then assumes that these measurements have a very high degree of precision (or at least we can ignore the uncertainty). This by itself invalidates your argument. There may be a useful contribution you can make here, but at present it appears to be through (like BP) being a useful case study of the faulty reasoning of so-called climate sceptics. -
Maarten Ambaum at 20:55 PM on 16 November 2010How significance tests are misused in climate science
Dear Eric L., In my opinion you are making too much of the frequentist vs Bayesian discussion. I think it is not that central to whether you think significance tests are useful or not. Also a frequentist would agree with the statement that the p-value does not contain enough information to calculate the probability of the truth of a hypothesis, or the null hypothesis (such statements can be perfectly well framed in frequentist terms). Regarding the dendrochronologist, this is an example that is very interesting. Equation 6 in my paper states how to view this. It is simply Bayes equation written in terms of prior and posterior odds: posterior odds = prior odds x p(M| not N) / p(M|N) where I used the notation as in the post above (note the p(M|N) is the p-value). So whether your confidence in the global warming hypothesis has been increased by your tree work depends on whether the p-value is smaller than the probability to see your measurement in situations that we know there is global warming. This statement is independent of the prior odds; the actual posterior odds of course do depend on the prior odds. In other words, every single measurement increases our knowledge (changes our confidence in a hypothesis) in the same way; this is independent of whether you were a "believer" or not to start with. This discussion is getting quite long now. I will probably write another post with some of this stuff in sometime soon where I can also comment on the suggestion by HumanityRules. I think John Cook agreed that I could send in another guest post about this subject anyway. Best wishes to all and thank you very much for your interest in this post and for an interesting discussion, Maarten Ambaum -
Riccardo at 20:19 PM on 16 November 2010Ice-Free Arctic
muoncounter you should distinguish between BC absorption in the atmosphere and on the ice surface. I was referring to the latter which directly influences the ice melting. -
David Horton at 17:41 PM on 16 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
Oh and John Harrington at #32 - why, I wonder, would you repeat an anonymous anecdote like that, and, what's more, to use it as an example of "how science works" in general? It couldn't be, could it, that you are intending the reader to say "Oo yes, that must be what is happening with global warming, all the honest skeptics are being bullied, so the truth can't come out." That wouldn't be the intention would it John? I have been a scientist for over 40 years - the scenario you suggest is nonsense. -
David Horton at 17:35 PM on 16 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
The list of things attacked don't just have in common the people doing the attacking (eg Singer), and the methods used (down to a fine art, or what?), but also the nature of the argument. In every case these people are determined that (a) nothing will get in the way of business and (b) that nothing humans do can possibly damage the planet (or themselves). There is no doubt that the opposition is ideological, and business-related, nor any doubt that the techniques used, and the motives for using them, are found on blogs all over the world, including, not least, this one. -
SoundOff at 17:11 PM on 16 November 2010Economic Impacts of Carbon Pricing
I’m agnostic about which method should be used but I lean towards Cap & Trade if it’s done right. Part of right is a meaningful cap and no (or few) free allocations handed out at start-up. I worry somewhat about the trading mechanism (will we have CO2 derivatives?) but I think the biggest issue is measuring the emissions of all the players to see that they actually stay within the allocations they purchase. It’s workable when the number of players is relatively small, as was the case for sulphur emissions by power plants to combat acid rain. I don’t have the expertise to assess whether society can monitor GHG emissions with the necessary resolution – player by player – though I think so for the larger players. And I don’t know that the idea of returning C&T revenues to the public coffers to reduce taxes is really productive, as some have suggested be done. That just removes the capital from the innovation process that will find new low emission means of energy production, manufacturing, etc. and the subsequent updating to use that new technology. It just prolongs the problem. Can others fill in some of the blanks? -
Climate cherry pickers: cooling oceans
Ken Lambert - Actually, there is considerable and ongoing effort in merging together and cross-calibrating TSI series, as I have referred you to previously. See here and here. Those are the top two results from googling "satellite TSI", hardly difficult to find. Your statement (that TSI measurements aren't being merged) is simply not correct. On your other argument, regarding time integrated TOA imbalances - I consider the closed loop integration you have been pushing to be overvaluing the accuracy of the various measurements over the last 150 years. You don't seem (IMO) to be treating the TSI, TOA infrared, and various forcings with the caution needed given the accuracy of our knowledge, and interpolate from 1750 on assuming perfect accuracy. That's simply not supportable. What we do know, and have measured, are not absolute TSI's and forcings, but rather time-resolved points of deltas in forcings; when they have changed to some extent. And we can correlate those with multiply-supported temperature changes to determine the dominant forcings and responses over time. Your black-box integration from 1750 on (assuming perfect knowledge) leads to contradictions with deltas, orders of magnitude, and observed responses. You are simply too focused on what you see as absolute values. -
Phil263 at 16:09 PM on 16 November 2010Economic Impacts of Carbon Pricing
SoundOff@36 & Composer99 @ 37 The main advantage of market solutions such as C&T and carbon tax is that it internalise external costs into the cost of the polluting process. For that reason, this approach for dealing with externalities is preferred by most (neo-classical) economists over the regulatory approach. Businesses on the other hand tend to prefer regulations as they generally have the lobbying power to influence the design and implementation of regulation and make it as "toothless" as possible. Pricing carbon on the other hand (either through a carbon tax or using C & T) means that the cost of polluting has to be met and passed on. This is one of the reason why conservative political parties (eg the opposition in Australia) favour regulation and resist the adoption of a C & T scheme. They prefer calling it a "carbon tax" as this sounds very "evil" when it is actually a market based solution. -
The Skeptical Chymist at 15:54 PM on 16 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
John Harrington 11.42 AM While it is true that genuine areas of scientific debate/disagreement can get heated and divisive, the story you relate seems very outlandish. I would also disagree with her view of "modern science". Getting papers through peer review can be hard and the system doesn't work perfectly, but it's neither a sham nor corrupt. -
Composer99 at 14:53 PM on 16 November 2010Economic Impacts of Carbon Pricing
Might I add that government/international regulation of pollutants (either a cap and trade on sulphur emissions or the phase-out of CFCs has been succesful in the past. As such, there is no a priori reason why some effort to regulate carbon emissions in a similar manner is destined to fail. Further to SoundOff's comment #36, airport security is as bad as it is because governments perceive the need to be seen doing something immediately. This leads to such wonderful ideas as full-body scans. Personally, I'd prefer that they take steps now, carefully and rationally, to do something about greenhouse gas emissions instead of trying to be seen doing something about them in a panic in 10-15 years. -
Phila at 14:39 PM on 16 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
sout: There is a huge amount of 'value added' by meeting people in person and having hundreds of people come together to listen and discuss face to face. Agreed, and I think this is especially true of Q&A segments. That's often the most important part of these events, and it's much harder to connect with audience members — undecided ones, especially - through videoconferencing. It's very important to do presentations like this one in person, IMO (and to make the footage widely available online, during and after). -
Phila at 14:30 PM on 16 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
johnd: Phila at 10:51 AM, the point I was making is that perhaps there are other problems that may reach a crisis point well before any climate change realistically impacts to any great extent, and priorities and attention be adjusted accordingly. So I gathered. Regardless, it's a false dichotomy, not least because some of these problems have the same root causes or ideological obstacles, and the same people counseling inaction and complacency (or recommending that we shift our attention to "real" problems, a la Bjorn Lomborg). If people need to feel better being described as "needing to address" Since my comment had nothing to do with how people "need to feel," this reply is puzzling. My suggestion was more for your benefit than anyone else's, and was less about making other people feel better than helping them (possibly) to take your statements a little more seriously. -
Miriam O'Brien (Sou) at 14:21 PM on 16 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
In response to comments about a webcast or similar being preferable to a tour, I have to say the Oreskes is getting a large amount of publicity here that she would not have garnered from a webcast; including on national radio and television. I agree (and promote the use of) video conferencing - eg for meetings of national and international groups - for dealing with ongoing matters. But only if there are also regular (if less frequent, eg annual) face to face meetings. There is a huge amount of 'value added' by meeting people in person and having hundreds of people come together to listen and discuss face to face. -
Ken Lambert at 13:37 PM on 16 November 2010Climate cherry pickers: cooling oceans
BP #26 Some knockout points BP. I am indebted to you for opening my eyes to the OHC story and the impossible jumps and bumps in the von Schukmann graph and the critical point that OHC increase must be the integral of the TOA forcing imbalance wrt time to be consistent with the first law. The impossible jumps OHC in the 2003-04 period can only be explained by dud Argo measurements OR as an offset - an artifact of the transition. My contention is that Argo is also not perfect and the 'gold standard' is a tethered buoy system measuring the same tile of ocean at the same referenced time T1 and again at T2 all over the planet as the only accurate way of measuring OHC differences over the T2 - T1 period. How close Argo comes to that 'gold standard' no-one seems to know. The SLR graphs showing TOPEX spliced to Jason also are candidates for offsets at the transition where the SLR slope has reduced with Jason compared with TOPEX. Strenuous effort has been made by AGW protagonists to claim that these transitions are calibrated to be seamless, however the point is made that the latest satellite instruments must be more accurate and repeatable than earlier instruments with diferent gains and inferior technology. Also no-one is seeming to splice TSI measuring satellites together into a continuous record probably due to a -4.5W/sq.m unresolved difference in the latest SORCE TIMS satellites and prior measurements by earlier satellites. That is one helluva offset. -
SoundOff at 13:34 PM on 16 November 2010Economic Impacts of Carbon Pricing
Some believe any government intervention puts us on slippery slope to world socialism. If they admit climate change or warming is occurring and has human causes, then they also admit the need for government intervention. They won’t do that. The irony is that the more they delay political and economic action to correct this problem, the greater the crisis will become and eventually much more radical government interference will be needed than if we had started addressing the problem earlier. Imagine, perhaps, CO2 rationing. We only need to look at airport security today to understand how much governments will spend when they perceive a matter to be urgent, and the freedom we will lose in the process. -
muoncounter at 13:21 PM on 16 November 2010Ice-Free Arctic
#73: "doesn't tell much about the causality between the two." Hopper et al 1994 reiterate my point in #71 ... hourly black carbon data exhibited considerable episodic behaviour over periods of a few days to a week. These elevated concentrations of black carbon were most often correlated with increases in carbon dioxide and methane concentrations. Such correlations can arise from several causes, but transport of a polluted air mass from industrialized regions to the high Arctic would account for the simultaneous increases in numerous monitored constituents, and is consistent with previous studies of Arctic Haze. Black carbon is apparently a valid 'tracer' for carbon dioxide. BP in his considerable wisdom now strengthens the link between Arctic melt and atmospheric CO2. To take this one step further, black carbon transport is apparently affected by ocean oscillations. From Sharma et al 2006: The results revealed that EBC concentrations were 40% higher during the positive phase of the North Atlantic Oscillation than during the negative phase. The source contributions at the two sites were determined by using trajectory analysis techniques, which revealed that Alert came under the influence of Siberia/Europe transport while Barrow showed influence from Siberian and Pacific/Asian transport. This suggests the end of the 'its all because of ocean oscillations' tripe. The varying wind and weather associated with ocean oscillations are merely the agents that modify the transport of GHGs from anthropogenic sources to the Arctic. -
johnd at 12:14 PM on 16 November 2010Naomi Oreskes' Merchants of Doubt Australian tour
Phila at 10:51 AM, the point I was making is that perhaps there are other problems that may reach a crisis point well before any climate change realistically impacts to any great extent, and priorities and attention be adjusted accordingly. If people need to feel better being described as "needing to address" rather than agonising over many of the issues whilst little is being achieved, or wringing of their hands, then perhaps that is the most telling point of all with regards to being able to set priorities.
Prev 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 Next
