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Comments 69551 to 69600:

  1. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    With great irony, I have just finished a post that establishes yet another of Arkuiusz' frequent misquotations to find him claiming that he is falsely accused of cherry picking. Of course, deliberate misquotation is just another form of cherry picking (and a particularly deceitful form of it). So, having given us yet another example of cherry picking, he then denies that he practices that vise in the very next post. As I said, very ironic. More relevantly, Arkadiusz' 48 is in fact irrelevant to this topic, and he has kindly highlighted for us the reason why it is irrelevant.
  2. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Arkadiuz Semczyszak @47, quotes from Chung and Räisänen 2011. However the full paragraph from which he quotes read:
    "If the models simulate climate feedbacks correctly, the indication is that models have significantly incorrect climate forcing. Since GHG forcing is well established, the problem is likely in how the models treat aerosol effects. In this scenario, the real aerosol forcing might be significantly positive in the Arctic and significantly negative outside of the Arctic, while the models miss this feature entirely."
    Clearly the conditional statement which Arkadiusz omitted is crucial to the meaning of the authors. In fact they are presenting one of three possibilities which their study is unable to distinguish between - the other two being that tropical feedbacks are overestimated, and that arctic feedbacks are underestimated. By omitting the conditional, Arkadiusz has quoted a conditional as a firm conclusion of the study. In fact, a recent study, Flanner et al, 2011, already finds evidence that the third option (which Arkudiusz misquotation conceals) of greater than predicted feedbacks is what is driving the unexpectedly rapid arctic melt:
    "Hemisphere forcing at −4.6 to −2.2 W m−2, with a peak in May of −9.0±2.7 W m−2. We find that cyrospheric cooling declined by 0.45 W m−2 from 1979 to 2008, with nearly equal contributions from changes in land snow cover and sea ice. On the basis of these observations, we conclude that the albedo feedback from the Northern Hemisphere cryosphere falls between 0.3 and 1.1 W m−2 K−1, substantially larger than comparable estimates obtained from 18 climate models."
    (My emphasis, see here for discussion on SkS) Taken together with Chung and Räisänen 2011, this suggests that models tend to underestimate climate sensitivity as Chung and Räisänen indicate.
  3. Arkadiusz Semczyszak at 19:17 PM on 25 November 2011
    Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    (-Snip-) None of the cited work does not settle here finally - objectively - last question - in this lengthy (sorry) quotation. My “alleged” - a typical “trick for skeptics” - "cherry picking" - use absolutely all the authors cited papers. Their subjective views on AGW have too much influence on the results - conclusions.
    Response:

    [DB] Tom again deconstructs your continued cherry-picking in comment 50 and its irrelevance below.

    Extensive block-quoting (from the Kobashi paper discussed earlier in this thread) without appropriate context snipped.

  4. actually thoughtful at 18:55 PM on 25 November 2011
    The Debunking Handbook Part 4: The Worldview Backfire Effect
    This is, I think, the key issue when dealing with so-called skeptics (that their world view prevents reality from getting within shouting distance of their opinions) WV Quine wrote about this in his book Web of Belief. Very interesting stuff. I have found, when posting on message boards, that if you make somewhat of a connection with a poster before "educating" them (my friend calls this hitting them on the head with a dead fish - making the sound "whop" - thus whopping them) - you don't necessarily get to agreement, but you might get to an agreement to think about it. And that connection can be relatively tenuous - something that gets the other person thinking about you as a human being - not a 'bot of opposition. I once achieved the effect by simply writing "That is the most rational post I've ever seen you make" (not calling him rational, just more rational than usual - which COULD have been taken as an insult). We ended up having a decent discussion. The most key point is that you can't change the 20% or so that are committed to being ignorant. You can change their behavior (ie trampolines and getting the gubment off our back) - but they will die believing that climate change is a HOAX.
  5. actually thoughtful at 18:45 PM on 25 November 2011
    The Debunking Handbook Part 4: The Worldview Backfire Effect
    What is a concern troll?
    Moderator Response: [DB] See here.
  6. Arkadiusz Semczyszak at 18:38 PM on 25 November 2011
    Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    „... language barrier ...” ... of course yes - but only the “language of statistics”. The standard deviation is huge for the whole range of variation described by proxy - to the nineteenth century. For this we must add: „...extensive uncertainties remain, especially before the sixteenth century ...” For those who are “convinced” of the compatibility of temperature changes in the Arctic with the estimated GHGs forcing - in comparison - another forcing: Chung and Räisänen 2011 : Implications: “Since GHG forcing is well established, the problem is likely in how the models treat aerosol effects. In this scenario, the real aerosol forcing might be significantly positive in the Arctic and significantly negative outside of the Arctic, while the models miss this feature entirely.”
    Response:

    [DB] And with this you are back to your long-established practice of cherry-picking quotes, as Tom notes below in comment 49.  The practice for which you have been cautioned and warned against ad nauseum.  And which you have ackowleged with the intent to do better.  Yet here we are.

    Language barriers are no longer an excuse, as this behavior is demonstrably willful.  No more.

  7. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Mandas and others, The silly story about Erik the Red came from Hubert Lamb, first director of CRU and the man behind the MWP concept. That Lamb used it shows the primitive state of temperature reconstructions just a generation ago.
    Response:

    [DB] "The silly story about Erik the Red came from Hubert Lamb"

    Then you will certainly have no problem furnishing a link to support your Hubert Lamb claim.  If he did indeed use it, then you will have to furnish also the context in which he used it and then demonstrate why that is relevant to this thread.  Else you are being silly and off-topic and therefore this comment will be deleted.

    "That Lamb used it shows the primitive state of temperature reconstructions just a generation ago."

    This is certainly an unsupported, subjective and indeed off-topic comment.  Other comments exist here on models and their qualitative states.  The Search function will reveal many.  Continue this line of reasoning there, not here where it is off-topic.

  8. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    So far as I know, speculation about their level of subsistence prior to the eventual collapse is no more than speculation, and they were trading with Europe for a considerable portion of that time. They were there for a long time for the walrus ivory, not just to scratch out the barest existence imaginable, and lived in climate conditions comparable to some of those in parts of Iceland or Norway. But indeed that's for another day, we quite agree that it is utterly irrelevant for the topic and for AGW in general, despite skeptics suggesting otherwise!
  9. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    skywatcher @43 I concede to your point about surviving for about four centuries, but am not so sure I'd agree that they did "very well". We don't know how long they were in decline and thus we don't know how long they were hovering on or just below subsistance levels. True, the encroachment of the Inuit Thule culture was a major factor and one wonders whether competition for resources escalated to outright warfare. I expect the collapse of bow head whale resources was a result of increased competition for the same resource pool but admit that is just speculation. In any case, rather than lead this thread off topic, I see from your list of possible causes for the failure of the settlements we agree about what is relevant to AGW science. The failure of Norse Greenland cannot simply be sheeted home to MWP or LIA.
  10. World Energy Outlook 2011: “The door to 2°C is closing”
    skept.fr @42, I apologize for this late and limited response. I am very short of time at the moment, and as a result my commentary on more difficult subjects (including this one) has dropped of. Clearly I was in error regarding total energy consumption. That being the case, I would point out that if you are correct that the value of energy is not properly captured by its cost as a percentage of GDP, then expenditure on energy conversion will rise as a shortfall in usable energy develops, meaning conversion to RE will be faster than that suggested by SSREN scenarios. There can be no question that we could make the conversion to a zero carbon economy if we where determined to do so. Available solar energy is 11,000 times our current usage. Available wind energy is 78 times our usage. Available wave energy is 4 times our usage. (Figures from Richard Alley, Earth: The operators manual") Nor is there any question that we currently have all the technical expertise required. Even issues of intermittency are, as engineering problems, easily solved. What is not clear is whether they can be solved with low economic, social and ecological cost. In short, the issue of moving to a carbon free economy by 2050 is not can we, but will we pay the costs of doing so, where the cost is a small percentage of GDP. With regard to food, the IPCC AR4 indicates increases in temperature above 3 degrees C will reduce crop yields world wide. That is in addition to the loss of crop land due to changes in precipitation patterns. There will be similar losses in fishery production as warming water results in arctic (high oxygen) biomes being replaced by temperate and tropical biomes. On top of that there is a significant probability of the destruction of major barrier reefs, and in the long term the generation of anoxic oceans due to ocean acidification coupled with warming seas. It is the later possibility which represents the complete collapse of global fisheries (if they do not collapse before then due to the earlier, smaller effects of global warming coupled with over-fishing). So, from my point of view, the dilemma we face is the choice between a possible slowing of global growth in energy usage vs a probable decline in global food production. Faced with a population growing from 7 to 9 billion, it is the later which is the greater cause for concern. Unfortunately, and again I apologize for this, I will not have the time to argue these points in detail in coming months.
  11. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Marcus and Stevo #36-38, it's worth noting that the settlers on Greenland did very well for 400 years, and successfully adapted to climate change during their time there (onset of LIA). Their diet went from mostly terrestrial to 80% marine (Arneborg et al, you can tell from the isotopic composition of their bones) as they changed their diet to be mostly seals. So it wasn't a failure of their agriculture that killed them. It's fair to say it wasn't the cold alone that killed 'em (Diamond is out of date), could also be conflict with the Inuit, world economics and politics, disease, or some unholy mix of the lot. But failure to adapt is not something you can easily accuse them of, given what is now known from the archaeology.
  12. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Albatross @23 If there was a climate cycle, there is no reason why we should be near the top of the climate cycle and about to go into a cooling phase any year. It could be a 4500 year climate cycle that we are 300 years away from peaking in. But it seems a curious element of 'skeptic' psychology that no matter what cycle is proposed we are always nearly at the peak of the cycle and it is always predicted that temperatures will cool any year, or have been cooling since 1998/2002/etc.
  13. Climate sensitivity is low
    249, Eric, Q1: My opinion only, but no, I don't think a return to 285 is necessary, just desirable (but impossible). I do think a return to 350 is required, but also impossible at the current rate of action (meaning that by the time we start, we'll be lucky to hold it to 500 at this point, and as I described, I think getting it down once its up will be almost impossible). Q2: How do you propose that the carbon get into the deep ocean? There are natural processes that work on huge, huge ("global") scales, but not nearly so quickly as to naturally drawn down both atmospheric and ocean CO2 levels to a reasonable degree (although I could be wrong on this... this is where an ocean expert like Doug Mackie should step in. Perhaps he knows better. But otherwise, how does someone suck all of that carbon out of the air and oceans and put it in a form that will sink to the bottom and stay there? It is interesting to note two things. The first is that the 300+ gigatonnes of carbon that man has burned in fossil fuels so far (and we're still not done) took nature hundreds of millions of years to sequester underground. It took a mere 100 years to release it, but there is no reasonable way to match nature's feat and put it back. It can go into the atmosphere, ocean or biomass, but not very easily back into the ground. The second point is that I recently did a back of the envelope calculation, trying to figure out how much land would be needed to plant giant sequoia redwoods that could suck up the carbon and turn it into biomatter (trees). The answer, with some very optimistic fudging, was that 75% of the arable and agricultural land on earth needed to be covered with redwoods in order to drawn atmospheric CO2 back down to 285 ppm in the course of 100 years from today, assuming we planted those trees right now and also instantly stopped burning more fossil fuels. This of course presumes that all of humanity moves to deserts and other places of the earth so that we can exclusively grow food crops on the remaining agricultural/arable land. Of course, since that represents only 25% of the total, we must also assume that food production will drop by 75%. This implies that the population of the earth (currently 7 billion) must also drop as a consequence -- so that "solution" implies: 1) Plant sequoias immediately on 75% of the arable land on earth (completely ignoring the fact that sequoias will not grow just anywhere, and in fact could only grow in very specific environments) 2) Move the entire human population off of such land 3) 5 billion people must die (because there won't be enough land to produce enough food to feed 7 billion, but instead only 2 billion).
  14. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    skept.fr @39 and mandas @40 Agreed. Denialist arguments about the MWP consistantly fail upon examination and are greatly overstated in both extent and consequence.
  15. World Energy Outlook 2011: “The door to 2°C is closing”
    skept.fr @65 CO2 emissions from the reduction of steel are a very low percentage of total emissions. They can safely be left until much further into the energy transition. In the long term, coal can be replaced by charcoal for reduction, thus rendering the process carbon neutral. Direct heating is an important use of coal (and oil and gas). However, in all instances it can be replaced by heating using electricity, and in some cases could be replaced by the use of solar furnaces. Further, energy consumption for direct heating in industrial processes is included in estimates of total energy use. Therefore this is not an additional requirement on top of those already being discussed.
  16. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Well, I must admit I had heard every denier argument, but Lars @ #19 has produced the best one ever!! So the cousin of Erik the Red swam over two miles through Greenland waters and then swam back, carrying a full grown sheep. And that's your argument against climate change and for the MWP?? What is this, Poe's Law? If you believe that either happened or is even possible, I have a nice bridge to sell you.
  17. World Energy Outlook 2011: “The door to 2°C is closing”
    Document of interest in the debate: the IEA roadmap for CCS (2009) . About the economic cost of mitigation: "IEA analysis suggests that without CCS, overall costs to reduce emissions to 2005 levels by 2050 increase by 70%." But Joe Romm documents (#61) point to the opposite. Hard to decide. #63 scaddenp : yes, coal as a fuel and reducing agent (coke) in metallurgy is often forgotten. It is also used (for heat) in cement, glass, ceramic or paper industry, so these intensive processes must be included in the RE package if substituting coal rather than capturing CO2 from its combustion is the only option.
  18. Newcomers, Start Here
    Sphaerica @154, you are correct that my post was intended as a response to your 139 rather than your 143. I am sorry for the confusion, and would appreciate a moderator amending the original post to avoid confusion for any newcomers reading these posts. It is also true that I detailed what I consider the real reasons for Mars' weak greenhouse rather than explicitly rebutting the reasons you gave. I will correct that here. Before turning to that, I note that you raise another point as explanation of Mars low greenhouse effect, ie, the absence of H20. I of course agree that a mass of water vapour in the martian atmosphere equal to the mass of water vapour in Earth's atmosphere would substantially raise temperatures on Mars. However, the factors that weaken the greenhouse effect of CO2 on Mars (as given in 145 would also weaken the greenhouse effect of water vapour. What is more, my calculation that if the CO2 on Mars has as strong a greenhouse effect as it does on Earth, it would warm the planet by approximately twice what it does is not effected by the absence of water vapour. Hence, the absence of water vapour is not the reason for the unusually weak greenhouse effect on Mars. Turning to your explicit explanations from 139, you first state that on Mars there are few gases for CO2 molecules to transfer energy to by collision "...so radiation dominates, and energy transfer up and out is quick" It is certainly plausible that energy transfer by radiation is quicker on Mars than in Earth's troposphere. For newcomers, this refers not to the transit at IR photons (which is at the speed of light), but to the average time taken between absorption and emission of photons, divided by the average distance traveled by a photons between emission and absorption. Also note that this always refers to transfer of energy at a particular wavelength. Clearly energy transferred outside the wavelength of the absorption band of a greenhouse gas will leave the atmosphere at the speed of light. Plausible though that is, it does not follow that radiation dominates energy transfer within the atmosphere of Mars. Indeed, it is known that Mars has a distinct troposphere,ie, the region of the atmosphere in which convection dominates radiation as the means of energy transfer. The martian troposphere is about 45 km in depth. Further, it is known that the troposphere on Mars is dominated by convection because the lapse rate in the troposphere is that calculated for the adiabatic lapse rate, ie, the rate of change of temperature that results from convection in a dry atmosphere. In your post 139, you then go on to say:
    "In the Earth's atmosphere a very, very important piece of the puzzle is that closer to the surface, where the air is denser, CO2 absorbs IR, but before (usually) it is able to re-emit that energy, a collision with O2 or N2 transfers that energy to those molecules, which do then not as easily or as readily emit energy in the infrared. The end result is that surface radiation heats the CO2, and the CO2 heats the surrounding atmosphere. As one gets higher and higher in altitude the atmosphere becomes less and less dense, and the balance shifts, so that eventually radiation becomes the key factor, and CO2 acts to cool rather than to warm (i.e. collisions between O2/N2 and CO2 transfer energy from the O2/N2 to the CO2, which is then emitted as IR and potentially lost to space)."
    Unfortunately this only presents part of the picture, and draws the wrong conclusions as a result. The most important thing missing is that CO2 gains energy from collisions as well. How frequently that happens depends entirely on the temperature of the gas. The higher the temperature, the more frequently CO2 will collide with a molecule (of whatever variety) that has higher kinetic energy, and will receive enough energy to emit a photon as a result. Note that if the gas is cool, other molecules will draw of energy from a given CO2 molecule more frequently than they transfer energy to that molecule, and so absorbed energy will tend to be dispersed within the gas, thus warming it. This will be the case even if the gas is 100% CO2. Conversely, if the gas is hot, CO2 molecules will absorb energy from collisions more frequently and hence emit photons at a higher rate, thus cooling the gas. The average rate of emissions of the CO2 therefore depends entirely on the temperature of the gas, and is not effected by its composition (provided it contains some CO2). Composition does effect the rate at which the gas approaches equilibrium. Additional nitrogen or oxygen molecules will result in the gas taking longer to warm by the absorption of IR radiation. But it will not directly effect the rate of emission or absorption. (It will indirectly effect it by either increasing pressure if we do not increase the volume of the gas, thus resulting in pressure broadening, or by decreasing the optical thickness of a given depth of the gas if we increase the volume, but that is a separate issue.) Note that because the rate of emission depends entirely on temperature, whether CO2 cools or warms depends entirely on the temperature of the gas relative to the amount of radiation being absorbed. If on average a CO2 molecule receives more energy from collisions than from radiation, the net effect is to cool the gas. If the CO2 receives more energy from radiation than from collisions it warms the gas. In the stratosphere, CO2 cools the gas not because of altitude, but because the gas is heated by ozone absorbing ultraviolet radiation to a temperature far above that which would establish an equilibrium between absorption and emission for CO2 in the IR spectrum. Finally, and unfortunately, I also cannot find hard numbers on these points. I have long found that scientists have a distressing habit of using their scarce resources to conduct experiments that advance their knowledge rather than ones which would aid exposition of the basics of the theory. The hard numbers we are after here are, of course of trivial interest to working climatologists. (Perhaps we can persuade Science of Doom to look at the issue when s/he returns from their hiatus.) In the meantime, these illustrations will be of interest. The first shows the temperature profiles of Venus, Earth and Mars, along with an indication of their temperature without the greenhouse effect. The second shows the absorption spectra of Venus, Earth and Mars. You will notice the pressure broadening of the central CO2 absorption band, very obvious when comparing Mars and Venus, but also noticable in comparisons to Earth:
  19. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Interestingly, in the Kinnard 2011 paper, there is nothing but a little uwpard trend of sea-ice extent during the usual core 'MWP' 900-1200. And the sharpest decline before the 1950-2010 condition occured... during the LIA. From the authors : 'The pronounced decrease in ice cover observed in both our terrestrial and oceanic proxy-based reconstructions between the late fifteenth and early seventeenth centuries occurred during the widespread cooling period known as the Little Ice Age (about ad 1450–1850 (ref. 18)). Reconstructed Arctic SATs show episodes of warming during this period (Fig. 3f), but according to our results the decrease in Arctic sea ice extent during the Little Ice Age was more pronounced than during the earlier Medieval Warm Optimum.'
  20. World Energy Outlook 2011: “The door to 2°C is closing”
    My guess is that CCS, if it is ever used on a large scale at all, will likely be deployed as remediation (rather than mitigation) in the latter half of this century, to correct what will almost certainly be an overshoot in any safe or acceptable level of CO2 concentration. See for example the two slides on page 11 of this presentation. The audio for this talk (by Myles Allen) can be accessed here. This is a talk worth watching in its own right, anyway. Given the massive problem we face in decarbonizing our energy supply (and eventually, probably, the atmosphere itself) I don't see why we should write off any potential contribution to a solution at this point. I know, after having paid a fortune to the oil companies for having them extract the carbon from the earth, to have to pay them again for putting it back, is a bitter pill to swallow.
  21. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Clarification to my last posting. The effect of climate change on the Norse Greenland colony may have been that expanding sea-ice made communication between Greenland and Scandinavia more difficult. However this has little if any bearing on the fact that the colony failed due using inappropriate agricultural practices for Greenland conditions.
  22. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    As someone whose background is both historiography and history I'm surprised that Viking colonisation of Greenland is considerred to in any way significant to climate history. Eric the Red chose the name "Greenland" for marketing purposes in order to attract settlers rather than as an accurate description of the place he had spent three years exploring. The failure of the Viking settlement on Iceland is held as an example of how failure to adapt agricultural practices to suit local conditions will doom colonists to failure. Similar examples of such failure to plan a colony and fail to adapt to local conditions can be found in British and French colonial failures in continental North America. Again, climate change is not a factor in these failures. From an historian's perspective the failure of Viking settlement in Greenland is an entirely seperate subjuect to climate history.
  23. Memo to Climategate Hacker: Poor Nations Don't Want Your Kind of Help
    The fact is that most developing Countries will benefit far more from relatively cheap (in both the medium & long term) distributed energy generation projects(like bio-gas derived from various waste streams, coupled with localized solar, wind & micro-hydro projects) than they would from large, centralized power generation projects which will have a large land-use footprint, create enormous amounts of toxic waste and/or cost a lot in ongoing non-renewable fuel. I know which approach I'd pick if I was seeking to alleviate poverty....just as I know which approach I'd use if I was seeking to line the pockets of the big resource corporations (like Rio Tinto & BHP).
  24. World Energy Outlook 2011: “The door to 2°C is closing”
    It would depend on where you are for getting enough RE at that price. Also, you arent going to find an alternative to coal for steel-making any time soon.
  25. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Actually, on reading my copy of Jared Diamond's book "collapse", there is very strong evidence to suggest that the Greenland Colony was always close to collapse, with supplies from Norway being frequently required to keep it going. Of course, once the LIA hit, said supplies could no longer arrive as frequently-which caused the colony to finally collapse.
  26. Memo to Climategate Hacker: Poor Nations Don't Want Your Kind of Help
    You can read the full ALBA-LDC statement for Durban here . The original figures for 10,5 trillion $ additional investment in 450 scenario compared to Reference Scenario in WEO 2009 report are here and here .
  27. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Hem, not better (!), read for the last sentence : "This is the birth context of the 'Medieval Warm Period' context concept, in the 1960s".
  28. Climategate 2.0: Denialists Serve Up Two-Year-Old Turkey
    Blessthefall, You really do need to consult the comment policy as Daniel has advised you to do. Lots of people here offer differing opinions or "dissenting" views-- look at this thread, "The greenhouse effect and the 2nd law of thermodynamics", it now stands at 1000 comments, with many, many of those posts made by what you would call "dissenters", see posts by damorbel, RW1, and FredStaples. That is just one thread here at SkS. Like them, you are welcome to post, but there are house rules, and each one of your deleted posts has violated the house rules in one way or the other-- claims of corruption, complaints about moderation etc. If you have a point to make, consult the comments policy and check the vitriol, rhetoric etc at the door, and always back up your assertions with facts when possible.
  29. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Philippe : oh yes, sorry, not an English-native, I'm confused! For 'historiographic', it refers of course to historiography as methodological discussion about the validity of sources. Historical records nead a special treatment from comparatists (historians) so as to evaluate their quality, ie their level of 'truth' and 'alteration' as skywatcher noted it. But Lamb was a climatologist, not an historian, so he tended to use unselectively the historical records. This point has been criticized by Emmanuel Le Roy Ladurie (French historian of climate, not climatologist) and Philippe Alexandre. This is the birth context of the 'Medieval Warm Period' context, in the 1960s.
  30. Philippe Chantreau at 10:25 AM on 25 November 2011
    Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Not to be pedant skept.fr but I believe that the quality of being poor, outside of the financial sense, is called paucity (not poorness). Also I'm not so sure about the historiographic adjective. Not trying to diminish your post but, although I'm sure everyone got your point, good language does help comprehension. Interesting references.
  31. Philippe Chantreau at 10:14 AM on 25 November 2011
    Memo to Climategate Hacker: Poor Nations Don't Want Your Kind of Help
    Albatross, Dr Pielke has copiously demonstrated here the extent of his double standards. When challenged on it, all he could do was try to change the subject, so what else could be expected?
  32. Philippe Chantreau at 10:12 AM on 25 November 2011
    Memo to Climategate Hacker: Poor Nations Don't Want Your Kind of Help
    Illegal hacking, selective quote mining, misrepresentation. Some example these skeptics set forth, although it's standard ops from we have seen so far. I note that the "side" so vocal against climate action is also where the most belly aching is heard on helping poor countries. That tune obviously changes according to the need of the moment. Some ideologues are definitely adept at improvisation and can even be said to be "playing outside."
  33. Memo to Climategate Hacker: Poor Nations Don't Want Your Kind of Help
    It seems that the poor and those most at threat of AGW are running out of patience, Climate change: vulnerable countries consider 'occupying' Durban talks. Well, there you have it. It seems the hackers are engaging in criminal activity for all the wrong reasons (not that criminal activity is ever justified). That or their "noble cause" is just a front for their vendetta against climate scientists and them preventing action being taken to mitigate AGW. I'm beginning to think it is the latter. I see Dr. Pielke Sr.and his son have no trouble quote mining the stolen emails to further their personal agendas. Tsk tsk.
  34. Climate sensitivity is low
    Eric (skeptic), the highest levels (per the Antarctica ice cores) achieved at any point in the past 800,000 years was 298.7 ppm. Humanity has seen that in the rear-view mirror long ago. To an uncertain future with great temerity we go.
  35. World Energy Outlook 2011: “The door to 2°C is closing”
    The Global Carbon Capture and Storage Institute in Canberra is endowed with >$2 billion and is responsible for producing cost-effective, efficient CCS technology. The last I heard (2010) was that this was not expected before the 2030’s and was unlikely to prove commercially viable until the price of carbon reached $120/tonne. But at that price RE is going to be far cheaper. The Australian coal mining industry does indeed hope that deployment of CCS in countries importing its product will ensure a long-term future. That is simply unrealistic. Those countries will deploy the technology which produces the cheapest energy and by 2030 that will be RE. To suggest that CCS is going to be the technology of the future which enables on-going use of “clean” coal is wishful thinking.
  36. Climategate 2.0: Denialists Serve Up Two-Year-Old Turkey
    caerbannog #39, I've seen you post your excellent reconstruction in quite a few places now, and am yet to see a skeptic reply with an alternative of his own. I'm guessing you haven't seen one either?
  37. Climate sensitivity is low
    Sphaerica, we're never getting back to 285 anytime soon because there is an exponential decay from whatever level we are at. Q1: is it necessary to return to 285 (it may not be possible anyway)? Is a higher level ok? Q2: What about storage in the deep ocean, would that help the recovery prospects?
  38. Memo to Climategate Hacker: Poor Nations Don't Want Your Kind of Help
    And why didn't he release all of the mails two years ago. By holding back the truth he has allowed the ecofascists to suck the blood out of the poor for two whole years! FOIA has blood on his hands!
  39. Memo to Climategate Hacker: Poor Nations Don't Want Your Kind of Help
    The US has a $15 trillion deficit by using fossil fuels badly, eating to much and by pretending to create free markets. The responsibility for this is modern political ideology and economics (left and right). What has the deficit achieved?? Not a lot, politics in the US has taken a path for the worse, resulting in political trench warfare and lines drawn that can not be crossed. Even if $37 trillion dollars were needed world wide, it seems like a small price to pay considering the massive long term benefits in securing energy systems that will be around for thousands of years, rather than a 200 or so. I actually consider many AGW skeptics today to be modern luddites, afraid of the new and exciting world of real technology developments. For some time now, the real cutting edge has been in renewables and 'green' technology. It is really pushing people and companies to do more with less.
  40. Memo to Climategate Hacker: Poor Nations Don't Want Your Kind of Help
    Personally, I reckon that this is just a faintly plausible attempt at a 'noble' justification - I seriously doubt that concern for the poor is an actual motivation... And, as you eloquently point out, even if it were - it's wrong.
  41. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Lars #19, I'd be very careful about quoting events from Landnamabok or other Icelandic sagas as if they are perfect historical records. Undoubtedly they often contain a grain of truth, and many events, such as the settlement of Greenland clearly happened much as weere told, but individual events may have some storytelling alteration. Add to that, in this case, the story was written down a century after it was supposed to have happened. Fancy trusting exactly what happened in a single event to your great-great-grandfather around the death of Queen Victoria? There's a story from the sagas, which I'll paraphrase, of two wizards who lived on the south coast of Iceland and lived on opposite sides of a river coming down from the mountain. They have a dispute, and one, who is blind, is told by his servant that the other wizard has sent the sea rising in flood across his land. He asks his servant to bring him a cup of the water - it is not salty - so the wizard realises the flood is from the mountain, not the sea. He goes and commands the floodwaters to leave his lands and flow down onto his enemy's lands. Their dispute continues, each sending floods down from the mountain onto each other. The place in south Iceland really exists, there are deep jökulhlaup flood channels in the mountain-side either side of the Sólheimá river, and there are well-dated flood deposits of about the right age (soon after Settlement of Iceland) that spread into the fields of the early farms. The mountain is the volcano Katla, covered by the Mýrdalsjökull ice cap, which has erupted on average every 50 years throughout Icelandic history. But do you literally believe that wizards moved the waters about? Of course not! Maybe the guy did swim the fjord to get his sheep - there's video of the 'ice man' swimming in the glacier lagoon Jokulsarlón too - or maybe the story got altered a bit in the retelling a century later. I certainly would not want to estimate a water temperature from a single story 1000 years ago written down 100 years after it was told!
  42. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    @18 TruthAtLast: Nope, the 1500 year (+/- 500 years!) only holds in ice cores from the Northern Hemisphere, while the opposite pattern is seen in the Southern Hemisphere. In other words, it's a polar see-saw, not global warming. They're called Dansgaard-Oeschger events. Today, both hemispheres are warming.
  43. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Bugger, left out a quotation mark. Now fixed.
  44. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Skep @28, Here you go.
  45. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Rob Painting : thanks for explanations, but '404 Error File Not Found' for the Lee 2011 reference.
  46. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    Lars #19 : Interesting. As you know, Lamb coined the terme ‘medieval warm period’ in his famous 1965 paper. Historical climatology, that is reconstruction of past climates by historical archives rather than physical or chemical proxy-based analysis, has known many evolution since the founding works in the 1960s, 1970s and 1980s. In particular, Lamb has been criticized by some researchers because of the scarcity of records, the poorness of their historiographic interpretation and the inherent difficulty of statistic extrapolations to large area. (A French book from a PhD thesis had been devoted to that re-evaluation of Lamb’s work, Alexandre P, 1987, Le climat au Moyen Âge, EHESS ; see also Hughes et Diaz 1994 for the re-analysis of previous MWP studies.) The story of Thorkel Farserk, cousin of Erik the Red, is typical of these uncertain records used in the first generation of historical climatology : one event in one season in one year, a possibly ‘pretyffied’ story (it has been suggested by Viking specialists that Erik the Red an co-founders were good propagandists for settlement in the new and ‘green’ land), etc. All that is too imprecise to infer a mean seasonal or annual temperature for whole Greenland, and of course for the whole Arctic circle (recall that we are speaking of sea-ice extent, not the Southern coast of Greenland). Anyway, it seems that Europe, and particularly Northern Europe, have known warm summer conditions one millenia ago. For example this work of Goosse et el 2006 ('al' including M. Mann) : ‘Proxy records and results of a three dimensional climate model show that European summer temperatures roughly a millennium ago were comparable to those of the last 25 years of the 20th century, supporting the existence of a summer “Medieval Warm Period” in Europe.’
  47. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    skept.fr @ 15 - "Rob Painting #5 : the point is unclear for me. On this Mann MCA / present comparison, part of the North Atlantic basin seems warmer too during Medieval period, so isn't it sufficient for the advection of heat water you refer to?" I think you will notice that the reconstruction in Mann (2009) reveals a very localized patch of ocean warming in the North Atlantic. The overwhelming majority of the ocean during medieval times was cooler than the 1961-1990 baseline, especially the rest of the Atlantic. This is just consequence of the two very different processes operating between the two intervals. We know elevated CO2 levels were not responsible for the medieval climate, but today we have levels of atmospheric CO2 not seen for perhaps as long as 20 million years. This is crucial because elevated greenhouse gases, such as CO2, trap more heat in the ocean on a global scale. Therefore ocean heat content today is much higher than medieval times - there is simply more of it in the Atlantic today to melt the Arctic sea ice. Take a gander at Lee (2011) - What caused the significant increase in Atlantic Ocean heat content since the mid‐20th century?, particularly figure 1(a) and (b). As discussed in an earlier SkS post, the MWP seems to have been a re-organization of the global climate. Despite the localized warming aroung Greenland, the global mean background state was much cooler than today.
  48. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    "WUWT claims that "during the peak of MWP glaciers were smaller than today"" Wouldnt apply to any Southern Hemisphere glacier that I am aware of. Of course LIA wasnt particularly pronounced in SH.
  49. Arctic Sea Ice Hockey Stick: Melt Unprecedented in Last 1,450 years
    TruthAtLast #18, Watch this, and try to pay attention. http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=385x275077
  50. Correction to the True Cost of Coal Power - MMN11
    "In fact, a recent Economics for Equity and Environment Network report concluded that the SCC in 2010 likely lies between $28 and $893 per ton, and will rise in 2050 to between $64 and $1,550 a ton." Wikipedia puts 2008 emissions at 29,888,121,000 tons. That times 893 is 26.7 trillion dollars. That doesn't seem plausible, it's around 40% of global GDP.

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