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Comments 107101 to 107150:

  1. Carbon Dioxide - Everyone's Favorite Pollutant
    BP writes: The shift in costs alone should be enough to provide an incentive. Yes, I agree. BP continues: But having accomplished that much, there is no legitimate justification whatsoever for governments to keep the money and use it for inflating bureaucratic power structures through sponsoring pet projects with public money. Government is seldom wiser than the people in allocating resources, therefore carbon taxes should be fully refunded, let's say through VAT allowance. That's a purely subjective political preference. There's nothing inherently wrong with, say, taxing carbon and using the money to support health care or the military-industrial complex or whatever. That said, I happen to agree that the best option would be to refund effectively 100% of the revenue from a carbon tax to individuals (on a per capita basis). But I try to avoid saying things like "there is no legitimate justification whatsoever" for subjective policy preferences that happen to differ from my own. BP continues: [I]f taxation is based on the theory CO2 is a pollutant the general message is that anyone who can afford it, is free to pollute the environment. A detrimental message, especially because there are actual pollutants causing immediate harm, but still released into the environment unabated because it's much cheaper to pay the fine than to control emissions. Different pollutants have different impacts. There are some cases where essentially no release into the environment is acceptable. At the opposite extreme, in other cases (CO2, SO2, agricultural fertilizers, etc.) the total elimination of anthropogenic fluxes into the environment is neither necessary nor cost-effective ... but limiting the magnitude of the flux is necessary (to prevent AGW, acid rain, harmful algae blooms, etc.) Two methods for doing this are (1) directly regulating emissions, or (2) using taxes or other incentives to keep emissions low. It's true that (2) will "allow anyone who can afford it to continue to pollute the environment", while (1) is more "democratic". On the other hand, given your dislike for "big government" I would think you would prefer option (2), which doesn't involve governments making decisions about who can emit how much for what purpose. BP: The second reason is even more serious. There are legitimate, even natural sources of carbon dioxide emissions, in fact life on Earth as we know it would cease to exist as soon as one would succeed in stopping all emissions. Therefore the theory goes on differentiating between natural and anthropogenic sources. However, at the point of emission no such difference exists. [...] Of course one could attempt to make wearing gas masks obligatory in order to be able to measure this particular source of emission and tax it accordingly, but I don't think any politician who would go for such a move could keep his office for long. Please don't waste our time with stuff like that. Talk about forcing people to wear gas masks, stopping all non-fossil-fuel emissions, and ending life on earth just degrades the quality of the discussion. You would be much better off if you made a bit more effort to resist the inclination to set up and defeat absurd straw-man arguments that no actual person supports. BP then returns to the sphere of the reasonable, by suggesting that the appropriate way to impose a cost on fossil fuel emissions is by a tax on mining (coupled with his ideologically preferred redistribution of the resulting revenue to everyone). This is fine, and could have been usefully expressed without all the preceding baggage. Unfortunately, BP then goes on to conclude with But it can't be done based on the theory CO2 is a pollutant, because in case of real pollutants it is the emission that should be regulated (as opposed to simply taxed) and rightly so. [... For CO2,] a separate set of rules and regulations should be applied which is practicable only if CO2 is assigned to a different category under public nuisances, other than pollutants. This is purely circular reasoning. You've created a definition of "real pollutant" that essentially translates to "things that behave a certain way different from CO2" and then conclude that CO2 isn't a pollutant. However, many people on this site, and many national and international organizations, don't agree with your strictly limited definition of "pollutant".
  2. New temperature reconstruction vindicates ...
    #145. You are not serious. You use like 2 year trends to prove "accelerated warming". Plus some heavy La Nina- El Nino -cherrypicked trends. Your comparisons were as valuable as this: Nice cherrypicking mate. The problem is that any other shorter interval also includes a lot of noise from weather phenomenoms. Therefore you need to draw the lines from CREST-TO-CREST, on ENSO-neutral intervals. 1998 to 2010 is one of those intervals, and there is no statistically significant warming there. Also a note for the Neds original post: The Lundgqvist data ends on 1999 so therefore you need to ONLY add the temperature increase since then (with 10yr smoothing). Your "method" to add the thermometer data is HIGHLY suspicious, since the NH hasnt warmed since 1990 any more than 0.4 degrees. Best way would be to add the 2000-2009 decadal mean as a spot to the end and THATS IT. Even Taminos version shows its only 0.2K warmer than on MWP: (note that he didnt add any thermometer comparison to Loehle and THEN offset to the mean, therefore his offsets are bogus only to support his preconceived notions): And the error margins on MWP are about +-0.2K Also, from the paper itself, please read the actual paper before making such "comparisons": "a very cautious interpretation of the level of warmth since AD 1990 compared to that of the peak warming during the Roman Warm Period and the Medieval Warm Period is strongly suggested." Your comparisons DO NOT fall into category 'very cautious interpretation'. And from McShane&Wyner pg. 3: "It is not necessary to know very much about the underlying methods to see that graphs such as Figure 1 are problematic as descriptive devices. First, the superposition of the instrumental record (red) creates a strong but entirely misleading contrast. The blue historical reconstruction is necessarily smoother with less overall variation than the red instrumental record since the reconstruction is, in a broad sense, a weighted average of all global temperature histories conditional on the observed proxy record. Second, the blue curve closely matches the red curve from 1850 AD to 1998 AD because it has been calibrated to the instrumental period which has served as training data. This sets up the erroneous visual expectation that the reconstructions are more accurate than they really are." Therefore the thermometer data is actually not even comparable to proxy data. And your methods HIGHLY problematic.
  3. Explaining Arctic sea ice loss
    Can't help but wonder if we shouldn't be looking more at the holocene to help us determine what we are getting into now. That looks like the time humans made it to Iceland and Greenland and it was by boat from the west. Of course its a lot easier for a band of nomads to survive a gradual climate change than for 6 billion to survive a more sudden change. Now I submit that climate change is like politics in that it all comes down to local. The holocene is believed to be regional. I wonder if someone looking back 5000 years from now might say the same thing. Though changes are happening faster now it still affects regions differently. AGW is now real for Russia and Korea with major crop failures and deaths. Here in the US it wasn't a great year for crops but we can survive it. If the weather patterns change Russia may have a good wheat crop and the US could have major crop failure. So even though its a global problem by squinting your eyes you might be able to only see regional problems.
  4. Explaining Arctic sea ice loss
    The Inconvenient Skeptic and Ned, The AMO is undoubtedly contributing to the current warming in the North Atlantic and likely does contribute to the loss of sea ice in the Arctic. I believe the AMO also correlates extremely well with Arctic and North Atlantic air temperatures. However the AMO cannot alone explain the significant reductions in Arctic sea ice without including an anthropogenic signal. The AMO in its positive stage represents an intensification of the THC bringing more warm water to the North Atlantic. In the past when the positive phases have occurred it is true that ice losses have subsequently occurred, but I would find it highly suspect to suggest that the Northwest passage was open fully in one year, let alone 3 in a row.
  5. It's the sun
    kdkd #688 You are actually looking sensible among some of this lot kdkd. I'm interstate for a few days - will catch up with you Monday. Maybe time to re-visit the karaoke and look for that CO2 saturation again.
  6. Explaining Arctic sea ice loss
    Roger, that's the basis of Bill Ruddiman's hypothesis (early anthropogenic influence on climate). See Plows, Plagues, and Petroleum if you haven't already read it. I am a bit doubtful. Also, there is at least some evidence that the present interglacial would have been relatively long even without anthropogenic meddling. A number of people think that MIS-11 (~400,000 years before present) is the closest analogue to current conditions, and it lasted much longer than the more recent interglacials. See Berger & Loutre (2002). It is difficult to be confident about this either way -- around 3000 years from now, summer insolation at 65 north will be very close to the value that triggered past glaciations. So while it's likely that this interglacial would have lasted another 50,000 years, if the glacial trigger is more sensitive then it's possible that the Earth would have started a slow transition into glaciation in the not too distant future. Of course, all this is out the window now, as you note, due to anthropogenic GHGs. (It also probably belongs in another thread....)
  7. It's the sun
    KR#687 So what do you find wrong with the baselines in GISS Fig 613 from Post #631 KR? I thought we agreed that circa AD 1700 - 1750 was a 'low temperature trajectory' - a Maunder Minimum in fact. Anyway kdkd seems to have no problem with 'holding all other variables constant' in order to ascertain the contribution of each. If one variable did depend on another in an identifiable relationship (lets say CO2 positive forcing is directly related to cloud cooling negative forcing) then the two variables could be treated as one with a known equation for the combined forcing. Go look at the CO2 forcing via the IPCC equation and tell me what the relative forcings are with Solar in say 1800, 1850, 1900, 1950 and 2005. In 2005 you can find Solar at about 0.3 - 0.4W/sq.m and CO2 at 1.66W/sq.m - hardly an order of magniude difference and only at the most recent end of the time scale.
  8. Explaining Arctic sea ice loss
    Fresh thread, inconvenient timing; the copy of the Polyak article at UCAR is unavailable right now, hopefully temporarily. In the meantime Google has a cached copy here.
  9. Roger A. Wehage at 23:03 PM on 13 October 2010
    Explaining Arctic sea ice loss
    Historical records of world temperatures from ice core samples over the past 410K years show rapid declines following peaks at 130K, 230K, 330K, and 410K years ago. However, in the last 15K years (not counting the industrial years), following the last dramatic temperature rise, global temperatures have remained relatively flat, with fluctuations varying by ±1.5°C or so. If history had anything to say about world temperatures, I would have expected a sharp downward trend, heading toward the next ice age. We see similar historical peaks in CO2. But about 15K years ago there was a small drop in CO2, only to shoot up again about 10K years ago, which might explain the stabilizing of temperatures. Are we overlooking a smaller human footprint on CO2 and global temperatures that may have extended back 10K years or so ago? When did man discover that systematic burning could be used to manage forests, and was that systematic burning more than what nature would have done alone? Put another way, has man been reducing forest stands for 10K years or more, which might be responsible for adding some CO2 to the atmosphere and stabilizing global temperatures? Man has also been burning coal and limited amounts of fossil fuels for thousands of years too. This would also have contributed to CO2, but maybe to a lesser extent than forest reductions. So, rather than nature returning Earth to the next ice age, man is turning it into a sauna. Is it a wonder that we are now seeing shrinking glaciers and ice caps when they should be growing?
  10. Berényi Péter at 22:56 PM on 13 October 2010
    Carbon Dioxide - Everyone's Favorite Pollutant
    #179 kdkd at 08:42 AM on 13 October, 2010 You imply that chronic pollution is not a valid form of pollution, and that only acute incidents should be considered. And that government should have no role in the provision of infrastructure. What an absurd set of positions! If CO2, although non-toxic, is supposed to be harmful in some intricate way, putting a price tag on emissions is a possibility. As KR #170 puts it "A major motivation for such taxes, however, would be to penalize CO2 emission, providing an economic incentive for current power companies and industries to individually (i.e., not by state-directed mandates or methods) transition away from CO2 heavy methods, and over to profitable alternatives. The shift in costs alone should be enough to provide an incentive. But having accomplished that much, there is no legitimate justification whatsoever for governments to keep the money and use it for inflating bureaucratic power structures through sponsoring pet projects with public money. Government is seldom wiser than the people in allocating resources, therefore carbon taxes should be fully refunded, let's say through VAT allowance. But this solution still lacks conceptual clarity, for two reasons. First if taxation is based on the theory CO2 is a pollutant the general message is that anyone who can afford it, is free to pollute the environment. A detrimental message, especially because there are actual pollutants causing immediate harm, but still released into the environment unabated because it's much cheaper to pay the fine than to control emissions. The second reason is even more serious. There are legitimate, even natural sources of carbon dioxide emissions, in fact life on Earth as we know it would cease to exist as soon as one would succeed in stopping all emissions. Therefore the theory goes on differentiating between natural and anthropogenic sources. However, at the point of emission no such difference exists. The CO2 we exhale (up to 300 kg/person annually) is produced by oxidizing food while the food production and distribution chain involves massive use of energy generated by burning carbon-based fuels reclaimed from the Earth's crust. Of course one could attempt to make wearing gas masks obligatory in order to be able to measure this particular source of emission and tax it accordingly, but I don't think any politician who would go for such a move could keep his office for long. This is a general problem with CO2 emission control. There are so many points and ways of emission, that controlling them all is both exceedingly expensive and quite impossible with no infringement on private life. The alternate solution is of course to go only for large scale industrial emitters, for even if all emissions are equal, but some must be more equal than others. You can surely see what a mess it is. I tell you anyone who maintains only recycling of carbon withdrawn long ago from the carbon cycle by age old geological processes poses public danger, should go for regulation targeting this very step, not emissions. Cap and trade is a preposterous bubble scheme and it is used exactly that way. Therefore if some market intervention is supposed to be necessary in order to reduce digging up carbon, the only rational way is to increase mining fees, refund the excess government income to everyone immediately through tax reduction and let people decide how to spend it. But it can't be done based on the theory CO2 is a pollutant, because in case of real pollutants it is the emission that should be regulated (as opposed to simply taxed) and rightly so. On the other hand with carbon dioxide, as we have seen, it is not the case. Here a separate set of rules and regulations should be applied which is practicable only if CO2 is assigned to a different category under public nuisances, other than pollutants. It is still rather difficult to negotiate a proper price to carbon mining. In theory it should be equal to all the environmental costs its use imposes on the public (even if actual pollutants like soot or sulfur are handled separately by emission control). Unfortunately the science is surely not settled enough to make such a rational calculation possible, so it would be a political decision anyway. But at least it's not a move toward even more concentration of power and away from common sense as present day pseudo-solutions are.
  11. What constitutes 'safe' global warming?
    Informative post. Now a days global warming is serious problem. Global warming is certainly a global issue that needs a global solution. There are lots of reasons for Global Warming. he Global warming occurs due to rise in the temperature around the earths atmosphere. We can make efforts to stop global warming. Ways To Stop Global Warming Use solar system appliances. Plant more trees. Do not cut trees. Turn off the lights when not in room. Cover your pots while cooking. This will save energy which is require for preparation of food.
  12. Explaining Arctic sea ice loss
    Oh, by the way -- nice post, Doug. Very clear and well written.
  13. Explaining Arctic sea ice loss
    kdkd #7: "The latent heat of melting of all that ice will account for a staggering amount of heat in the long run." The worrisome thought to me is, 'what happens with all that heat once the ice is gone?' Right now the Arctic ocean is heating up each year, but much of that heat is 'expended' melting the sea ice through the Summer (at an average rate of about 1000 km^3 per year over the past decade). There were only 4000 km^3 of sea ice left at the end of the 2010 melt season... down from the previous record low 5800 km^3 the year before. So if the average decline over the past decade continued the Arctic would be ice free in September in four years. Even the average rate of decline since 1979, 400 km^3 per year, would have the Arctic melting out in ten years. The Arctic ocean is going to continue accumulating heat. That heat is going to continue melting more ice each year and I can't think of any reason that the volume loss trend should suddenly change radically. Some amount of ice around the Canadian archipelago and other 'land sheltered' areas will stick around, but the rest seems clearly headed to melt out. So when the ice is gone and that heat starts building up rather than getting 'balanced out' by having to melt the ice it seems clear that it will mean a longer period before the ocean begins to refreeze. If so then the 'Arctic amplification' we've seen the last 30 years may be small potatoes compared to what is coming in the next 30.
  14. Explaining Arctic sea ice loss
    RSVP writes: Is it only coincidental that 90 percent of the world's industry is located in the northern hemisphere, and that this problem is not being seen in the Antartic? If the problem were only due to CO2 the effects would be symetrical, and they are not. Yes, it is coincidental. The distribution of CO2 is more or less uniform but the impacts of warming are distributed irregularly due to regional atmospheric and ocean circulation. This has been understood for decades, and is not some kind of "post hoc" explanation.
  15. Explaining Arctic sea ice loss
    The moderator writes: Moderator Response: AMO also is touched on by another post on Skeptical Science. Is it? I didn't see anything in that post about the AMO, just references to the Arctic Oscillation and the North Atlantic Oscillation. Admittedly I skimmed the page fairly quickly and might have missed it. That said, I'm not personally a huge fan of the various "oscillations" when used as empirically correlated explanatory variables for other aspects of climate. With enough of these oscillations (ENSO, IOD, AO, AAO, NAO, AMO, PDO, and am I forgetting any?) it's almost always possible to find one (or better yet a combination of two) that will correlate with whatever you're looking at, especially if the time frame is short enough.
  16. Explaining Arctic sea ice loss
    Excellent article. An ice free arctic ocean will likely be the Pearl Harbor event that will finally wake up the public, main stream media and possibly a few politicians. When that is going to happen is harder to say, but likely before 2030 and possibly before 2020.
  17. Explaining Arctic sea ice loss
    RSVP #3 Wow "Is it only coincidental that 90 percent of the world's industry is located in the northern hemisphere, and that this problem is not being seen in the Antartic" Is this another of those satirical comments designed to expose the weakeness and idiocy of much of the so-called sceptic case? The antarctic ice sheet many many times bigger than greenland. The latent heat of melting of all that ice will account for a staggering amount of heat in the long run. Roughly speaking, you're comparing apples with beachballs, and your analogy is correspondingly stretched to credulity and beyond.
  18. Explaining Arctic sea ice loss
    RSVP The Antarctic is a continent, not an area of the sea. Parts of it are very high above sea level, Mt Erebus is nearly 4000m high. Both of them are about 14 million sqkm. The Antarctic is much more exposed to cold being entirely surrounded by the chilly Southern Oceans.
  19. The sun upside down
    Joe Blog I was not trying to downplay the UV absorption induced stratospheric warming impacts on our climate. Although experimental evidence of the impacts during the 11-years solar cycle is not so well established, some features seems more robust and are qualitatively reproduced by models (see for example Haigh et al. 2005, Rind et al. 2008). But apart from the numbers, there's nothing new in Haig et al. 2010 for the UV range. What's really new is the "out of phase" change in the visible part of the solar spectrum. As Haigh herself pointed out, problems with the interpretation of the long term climate trends arise if this behaviour proves to be a general feature of the sun and not just linked to the 11-years cycle.
  20. Explaining Arctic sea ice loss
    TIS, early warming of the Arctic and associated decline of Arctic sea ice have long been conspicuous features of predicted effects of anthropogenic warming. Sorry to upset your sense of political correctness; these descriptions are supposed to lean on everyday figures of speech and in this case the term has been employed by various people involved in Arctic climate research. Maybe I should provide a reference though that seems a bit neurotic. RSVP, please read more carefully. "...research strongly suggests that today's decline is driven by the novel influence of anthropogenic C02 we've added to the atmosphere and thus is unique in Earth's history." Read the articles cited if you want to get a better grip.
  21. Explaining Arctic sea ice loss
    John, For every year since 2007 unreinforced yachts have made the North West passage in less than a month. There is no ice left there. As you point out, in 1906 the passage had to be completed on foot. This summer two yachts went entirely around the arctic ice, passing through both the North West and the North East passages. No icebreakers went with them. It is certainly unprecedented that the ice be completely gone from these areas in the historical record. Your assertion that icebreakers are currently required to make the passage is simply false- the ice has melted. Whalers have been going to the Arctic since the 1700's and they never saw either passage open. How do you explain the complete absence of ice in both the North West and North East passages with your "warm AMO phase"?
  22. Explaining Arctic sea ice loss
    doug_bostrom "...research strongly suggests that today's decline is driven by the novel influence of anthropogenic C02 we've added to the atmosphere and thus is unique in Earth's history." Typo: Earth's history, should be, Human history. That point aside, its not clear why the last paragraph was included, since the effect of anthropogenic CO2 on its own is not sufficient to produce these effects. Is it only coincidental that 90 percent of the world's industry is located in the northern hemisphere, and that this problem is not being seen in the Antartic? If the problem were only due to CO2 the effects would be symetrical, and they are not. In fact, the Artic is "protected" by more land and therefore should be even colder than the Antartic, and with oceans representing a truer averaging of temperatures.
  23. Carbon Dioxide - Everyone's Favorite Pollutant
    RSVP #181 The point here is that CO2 should not be considered pollution for its potential greenhouse gas effects, unless the same should be done for asphalt highways given that they are also warming the Earth in permanent fashion. However, as the chemical effects of CO2 on the environment are becoming a problem, then, yes, CO2 could be considered a pollutant. However, as I stated in earlier posts, there is a very sticky problem in terms of CO2 sources, as they can be natural or "unnatural", and thus it makes more sense to legislate the use of chemical sources as opposed to their byproducts.
  24. Carbon Dioxide - Everyone's Favorite Pollutant
    There is no doubt, unwanted CO2, unwanted H2O, unwanted rabbits, etc. represents something that needs attention for those affected. Climate change is going to be beneficial in some parts, and a problem in others, not unlike the effects of how a storm front distributes water for better or for worse. The effects of ocean acidification, on the other hand, is another story altogether, since the effect is cumulative, the oceans acting as a "finite" and fragile terminus. CO2 is upsetting the food chain, and thus affecting all life on planet Earth negatively. This fact should be sufficient to qualify CO2 as a pollutant, but instead the emphasis is place on its effects as a "greenhouse gas", which may or may not ultimately lead to warming or undesired results (i.e., ice free shipping lanes in the Artic have been sought by some for centuries). In addition, CO2 as a "pollutant" in virtue of its greenhouse gas effects is extremely vulnerable in that support of this idea depends on observable changes in climate. All it takes is for one significant radiative forcing to offset warming for public opinion to be lost altogether, (i.e. increased aerosols, etc), whereas the oceans will never stop absorbing the fallout.
  25. The sun upside down
    Riccardo "One would expect a negligible impact on tropospheric temperature." Yea, through direct radiative forcing UV is rather insignificant on the troposphere, it can however have effects on the pressure systems in the troposphere... And weather systems... It can have very measurable effects in the troposphere. Johanna Haigh has actually published a bit on it i believe.
  26. The sun upside down
    HumanityRules my bad, it was 3 over 1955 or 0.1% at 500 nm. The 6% change in the UV is probably not negligible for the chemistry and the temperature in the stratosphere. One would expect a negligible impact on tropospheric temperature.
  27. It's the sun
    KR #687 "with all other variables held constant" This is something you get for free in multiple regression models - you can examine the predictive ability of individual variables by holding all other variable constant - that 's what the various R2 values and other diagnostics give you. Ken didn't seem to get this when I went through this with him many aeons ago (using temperature anomaly as the predictor variable rather than TSI, but same diff ...).
  28. The sun upside down
    HR, the IPCC reports on climate are distinguished by their explicit discussion of the significance of uncertaintyu, in company with the NAS report from earlier this year and a few others. Compare the IPCC's care in explaining uncertainty with the structural failure of the just-released Royal Academy report. Meanwhile, you go on to make vague complaints about other scientists failing to address uncertainty in specific papers. Those publications are -not- aimed at the general public; you'll be hard pressed to find a paper based on observations that does not address uncertainty but equally you'll find it unusual for such papers to waste the time of their intended audience by providing remedial education for members of the lay public. Conveying a useful understanding of uncertainty to the proverbial man in the street is the job of science journalists.
  29. The sun upside down
    #13 There should be such caveats in all climate science papers. Caveats are much more the rule than the exception, as anyone who actually bothers to read such papers knows. Unfortunately, this doesn't stop "skeptics" from simultaneously accusing climate scientists of overconfidence, and demanding absolute certainty before we take action.
  30. The Inconvenient Skeptic at 13:58 PM on 13 October 2010
    Explaining Arctic sea ice loss
    The Atlantic Multidecadal Oscillation (AMO) is a natural cycle. It is also known to have affected the arctic sea ice before. The instrumental record of the AMO goes back to to around 1860. In that period there are approximately records of two full cycles of the AMO. Since it is only possible to directly correlate the sea ice extent to the AMO since the satellites were able to measure it in 1978 other means are needed to determine the affect in the past. The opening of the Northwest passage is one possible method. While the first credited successful passage was in 1906 (while AMO was cool) by Roald Amundsen, the expedition ended with the ship trapped in ice for 3 years and it was completed on foot. The first open water expedition was completed in a period of 28 months starting in 1940. The AMO was in the warm phase during this period. More interesting is that the trip back in 1944 only took about 3 months indicating that the ice volume had decreased since the initial trip. Many trips after that have succeeded, but using modern icebreaking ships with heavily reinforced hulls. Those were needed because the passage was once again closed while the AMO was in the cool phase. The transition of the AMO was once again transitioning to warm phase and has been above average since 1995. The re-opening of the passage since then correlates well to the warming of the AMO. Even the record low extent in 2007 correlates to the longest sustained warmth of the current AMO. After that the AMO has cooled slightly and the extent has rebounded. Separating any change in ice from the warm phase of the AMO would be a difficult task at best and claiming that the decreasing extent is the "canary in the global warming coal mine" is scientifically irresponsible. I do not claim that the AMO is the only factor decreasing extent, but it is certainly a major factor in the current extent behavior. John Kehr The Inconvenient Skeptic
    Moderator Response: AMO also is touched on by another post on Skeptical Science.
  31. Explaining Arctic sea ice loss
    'While it's true that natural variations of the climate have caused significant changes in Arctic ice extent in the past, it's important to note that such such changes are not airtight arguments against anthropogenic global warming causing today's loss of ice. After all, events of the past do not describe newly identified influences by human culture on today's climate. Indeed, comparisons between past and present Arctic climate reveal different reasons for yesterday's and today's Arctic sea ice changes and strongly suggest that today's changes are largely anthropogenic....' A useful discussion might be something on the lines of: When is the past a good guide to likely present and future outcomes? When not, and if not, why not? And vice versa. This would help reduce the plethora of claims and counterclaims about sea ice extent, volume and thickness, and how they are best measured. I confess freely to having added to this noise over the course of my visits to this site. Two very interesting looking papers which I'll be digesting at leisure with great interest.
  32. The sun upside down
    Re: HumanityRules (19)
    1. "I don't think you can just blame the press on this."
    I can and I do. They're abysmal. With the exception of Monbiot, I cannot think of anyone at all credible when it comes to science. Even Revkin has pulled a Curry: gadding about on a random walk of his own pretending in his kingdom of one to be centrist. End rant.
    2. "Many believe the IPCC do an equally bad job of presenting the limitations and uncertainties."
    Then they believe wrong. The IPCC is in a thankless position: trying to characterize the science caveated with uncertainties to laypersons who are lucky to find their head with both hands one time in three. Considering that, they do a brilliant job. End laud. All riled up now. I shouldn't do this in the middle of moving out of one house and into another. Getting downright peevish in me old age. The Yooper
  33. The sun upside down
    #19 HR:"I've never read anybody write Arctic ice is at an all time high" Did you miss this?
  34. The sun upside down
    14.Riccardo Not to be picky but I get the 500nm difference to be more like 0.1-0.2%. And a 5% change over a 6-7year period sounds like quite a lot to me. 15 Skywalker Yep I spend more time reading climate science papers than blogs. I'm definitely here to educate myself. I don't think you can just blame the press on this. Many believe the IPCC do an equally bad job of presenting the limitations and uncertainties. I also don't think all climate scientist are as open about this subject as Haigh is here. Obviously she's put it in her press release and it's prominently displayed in the abstract. There are many papers were serious caveats are buried in the results sections and never mentioned in the conclusions or abstract. This leads to a serious disconnect between the data and the conclusions. It's really what bugs me the most. 17 I get you're point (although I've never read anybody write Arctic ice is at an all time high). Sceptical blogs maybe need to be to the standard of newspapers while peer-reviewed papers are althgether different beasts, with different standards. Also Pielkes snr and Judith Curry's (and others) blogs for example are very different to your average lunatic rants. Even WUWT presents some interesting stuff (there's definitely a mix of Good, Bad and downright Ugly over there though). You're over simplifying the situation. Muon do you ever read WUWT? Do you ever find any of it challenging?
  35. It's not us
    doug_bostrom "You might ask yourself, how could it not be true that more "efficient" concentrations of GHGs in the atmosphere could leave evening temperatures unchanged?" Of course I am not implying that increased greenhouse gasses would leave evening temperatures unchanged I am implying that I do not think that there is an obvious reason that an increased greenhouse effect should increase evening temperature MORE than daytime temperatures. The Earth emits LW radiation at all times of day and in fact it emits MORE LW radiation during the day. So why is it "entirely implicit in the mechanism of GHGs"? Furthermore, I have indeed looked for papers in various search engines and I have consistently found that the literature attributes the changes in DTR to changes in one of a) clouds b) aerosols or c) land albedo. Here is another example: Stone, D. A., and A. J. Weaver (2002), Daily maximum and minimum temperature trends in a climate model, Geophys. Res. Lett., 29(9), 1356, doi:10.1029/2001GL014556. ABSTRACT: The recent observed global warming trend over land has been characterised by a faster warming at night, leading to a considerable decrease in the diurnal temperature range (DTR). Analysis of simulations of a climate model including observed increases in greenhouse gases and sulphate aerosols reveals a similar trend in the DTR of −0.2°C per century, albeit of smaller magnitude than the observed −0.8°C per century. This trend in the model simulations is related to changes in cloud cover and soil moisture. These results indicate that the observed decrease in the DTR could be a signal of anthropogenic forcing of recent climate change.
  36. The sun upside down
    I''d also like Humanity Rules to see if they can find even a handful of scientific papers that do not come with caveats and uncertainties. I suspect HR has read few or none. This is a very interesting development - the implications benefit no 'side' of the AGW blog debate.
  37. It's the sun
    Ken Lambert - "Where the Solar irradiance forcing crosses the axis is where TSI is neither warming or cooling the planet, in the absence of other forcings. Any disagreement with that?" In short, Ken, I absolutely disagree with that. You seem to have missed what I (and others) have said in many ways, on many posts. In particular, "with all other variables held constant". Is the temperature the same as the baseline starting point? Was the temperature trajectory at the start of this baseline period zero, with sufficient time at zero for time constants of ocean heating and secondary feedbacks to stabilize? (No on the last two points, incidentally.) Let alone the question on the other forcings, which have not held completely constant over this period. This is not a single variable system! Ken, do you understand that the GHG forcing changes over the last 150 years are an order of magnitude greater than the TSI changes over that period? Please answer that question.
  38. It's the sun
    archisteel #683 Oh - you mean THAT chart KL....the one for the last 1000 years. I find no problem with the concept of looking at each forcing component separately in order to ascertain the importance of each. We know that they all act in concert at any point in time. I am perfectly happy with GISS Fig. 613 reproduced from #631 in the absence of something better. Where the Solar irradiance forcing crosses the axis is where TSI is neither warming or cooling the planet, in the absence of other forcings. Any disagreement with that? This is what KR said at #650: "Ken Lambert - I would agree, there is one TSI for one equilibrium temperature of the Earth, with all other variables held constant" You have my permission to leave now archisteel if that is your desire.
  39. Carbon Dioxide - Everyone's Favorite Pollutant
    If we are going to stray off topic into the realm of "what should be done about it" policy, do you agree that net anthropogenic CO2 emissions are a pollutant? Arguing against a solution does not invalidate the problem.
  40. The value of coherence in science
    Just caught this on the Irregular Climate podcast e12. I had to register and say how wonderful that podcast was - it's worded so well and accessible. My mum asked a few years ago about this global warming thing. So I started out a lit. survey and found that Oreskes already had done it for me and published her finding in late 2005 Science. Job done as far as me and mum were concerned. But then on my gaming forum, deniers kept making odd claims that every time I investigated their claims, they would move onto other claims often contradictory to their previous claims but they could not see that. The contradictions they thought covered more ground thus they were more right. I tried to classify their points into 1)Earth is cooling 2)Earth is neither cooling or warming or we can't say for sure. 3)Earth is warming but not due to CO2 4)Earth is warming, due in part to CO2 but not our CO2 5)Earth is warming and it is CO2 but CO2 is plant food and warming good for us I assert that holding more than 1 of these positions at the same time is impossible for a sane person. They claim additional mutually exclusive points make a bigger net. The apples and sheep kill this claim like I could not. Thanks
  41. SkS Housekeeping: right margin
    John, you might want to add some feeds from relevant/interesting sites as I have done on my blog. It would be a service to SkS readers wondering if there was something new up at, say, Deltoid, and a quick pathway to check it out.
  42. Carbon Dioxide - Everyone's Favorite Pollutant
    BP #178 So as well as refusing to accept the bulk of scientific evidence that CO2 is causing global warming and has the potential to gravely harm the infrastructure of civilisation ... You imply that chronic pollution is not a valid form of pollution, and that only acute incidents should be considered. And that government should have no role in the provision of infrastructure. What an absurd set of positions!
  43. Berényi Péter at 08:23 AM on 13 October 2010
    Carbon Dioxide - Everyone's Favorite Pollutant
    #172 KR at 07:27 AM on 13 October, 2010 Prevention of harm is worth a huge amount. Indeed. If there's harm done it is. But the money belongs to those who have suffered and it is surely not government sponsored projects that are exposed to loss of life, health and property.
  44. Carbon Dioxide - Everyone's Favorite Pollutant
    #176: "Fossil fuel has given us a lot ... I don't think it's unreasonable to deal with the consequences of what we've gained." Unfortunately, that's exactly what we seem incapable of dealing with as a society. An economy fueled by generations of relatively cheap energy, with no thought of the cost of disposing of the waste product -- CO2. And now we have an industry dedicated to labeling any form of cost recovery as a "carbon tax" and thereby destroying it. Exactly the same mindset that allowed dumping of medical waste in the oceans until Title 3 was law - in 1991; exactly the same EPA doing the regulating.
  45. Carbon Dioxide - Everyone's Favorite Pollutant
    CoalGeologist - It's unfortunate, but the very topic of this thread is tied to legal and social issues, not just science. Defining a "pollutant" has the effect (in the US) of placing significant portions of the economy under controls that they did not have before, with social, legal, enforcement, and economic consequences. Fossil fuel has given us a lot, as you point out; I don't think it's unreasonable to deal with the consequences of what we've gained. As many have noted, however, the semantic games regarding "pollutant" are quite silly - the US legal definition is clear, and it would require a rather impressive re-definition of terms to change that.
  46. Carbon Dioxide - Everyone's Favorite Pollutant
    Berényi Péter wrote : "Consider for example the Doñana National Park mass-pollution in Southern Spain, committed by Canadian-Swedish owned Boliden Mineral AB on April 25, 1998. Cleanup cost $270 million so far (taxpayer's money of course), company payed nothing, filed for bankruptcy to avoid a meager $45 million fine." How easy it is to find the odd example that gives you what you want, if you are so pre-disposed. How easy it is to find more examples, and ignore them if needed, if they don't give you what you want : Bhopal - Union Carbide paid $470 million Gulf Oil Spill - BP covering the costs Love Canal - Oxy paid $129 million Minamata Bay - Chisso paid $80 million Abidjan - Trafigura paid $198 million Ok Tedi - BHP paid $28.6 million Exxon Valdez - Exxon paid $2.1 billion
  47. Carbon Dioxide - Everyone's Favorite Pollutant
    This is an interesting discussion. However, I am reminded, once again, that questions and issues related to what should be done to address problems related to anthropogenic CO2 emissions lie within the domain of politics, the law, and personal values & priorities, not science. This site specializes in, and focuses on, issues of science. Although the definition of "air pollutant" we've been discussing is admittedly a legal one, there are relevant scientific issues related to it, which I feel we have largely resolved through dialog. Questions related to response and remediation are much more complex and difficult and, to my understanding, are outside the domain of this site... or at least this specific topic. I would only add that although the underlying scientific theory of AGW has been around since ca. 1895 (Arrhenius), the hard data to prove it has been available only within the past 10-15 years. During the intervening time, the fossil energy industry has contributed substantially to improvement in the quality and longevity of life for billions of people. Admittedly, there have been negative consequences that have come along with this, some of them unforeseen, and certainly unintended. AGW is a problem we jointly face as a human population, as is the issue of energy supply. "Pointing fingers" will only complicate efforts to find solutions.
  48. Carbon Dioxide - Everyone's Favorite Pollutant
    Amelioration of the issue to prevent as much future harm as possible is giving it to "those who are supposed to be harmed", i.e. everybody.
  49. Carbon Dioxide - Everyone's Favorite Pollutant
    Berényi - Aside from the agricultural/habitat elements (mitigation of climate change) I listed as directed monies, moving away from CO2 pollution does "give it to those who are supposed to be harmed". To all of us, by preventing future harm. Unless you think preventing a meter of sea rise over the next century or so, increasing numbers of record heat waves (recall Europe 2003 - 40,000 dead? 2006?), agricultural disruption, etc., isn't worth anything??? This is exactly the (correct) reasoning behind the Clean Air Act and other anti-pollution measures. Prevention of harm is worth a huge amount.
  50. Berényi Péter at 07:07 AM on 13 October 2010
    Carbon Dioxide - Everyone's Favorite Pollutant
    #170 KR at 06:41 AM on 13 October, 2010 Why not give it to those who are supposed to be harmed?

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