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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 113301 to 113350:

  1. On the Question of Diminishing Arctic Ice Extent
    In images now available from Canadian and Danish sources, the beginnings of an ice free Northwest Passage can be seen. 7/22/2010 Denmark DMI/COI 8/3/2010 Canada 7/22/2010 Book your passage now!
  2. Confidence in climate forecasts
    I am appalled at the level of scientific misunderstanding... Uh-huh, or the less-than-ideal use of a word which does after all include "judge to be probable" among its meanings yet can't be used in this context because somebody will inevitably pipe up about weather forecasts. Rhetoric is important. So good point, it's a favorite talking-point of contrarians but not really indicative of any problem w/scientific understanding.
  3. It's cooling
    TomJones - the thermohaline circulation perhaps? If you watch the ENSO forecasts you will see cross-sections of the tropical ocean showing the downwelling. It doesnt escape detection.
  4. 1934 - hottest year on record
    doug_bostrom at 08:39 AM, I agree that it is the frequency of excursions, rather than the magnitude of individual excursions that are more relevant. For that reason I feel the Quinn reconstruction of El-Nino events is important to put more recent excursions into perspective.
  5. Confidence in climate forecasts
    I am appalled at the level of scientific misunderstanding shown here by Kevin Judd (and, presumably, John Cook). There is no such a thing as a "climate forecast". What climate models do is run “scenarios”, “what-ifs”, computations in which some parameters get changed, and everything else remains equal. That is a normal way of conducting risk analysis, but only if everybody keeps in mind that OF COURSE in the real world everything changes, and nothing remains equal. The surface temperature, for example, is also affected by unknown variables such as future volcanic eruptions and solar activity. Hence, the actual temperature difference between 2010 and, say, 2050, is pretty much unknowable. Climate models are therefore tools to probe risks and sensitivities, not crystal balls. As a matter of fact, they can’t, won’t and never will tell us anything precise about future weather, weeks, months, years or centuries in the future: just as no donkey will ever win the Kentucky Derby. That doesn’t mean climate models (or donkeys) are useless: rather, they should be used for what they are worth using. And yes, you can ask Gavin Schmidt if you don't believe me ;-) ps some will say that the difference between "forecast" and "scenario" is lost among the general public. Well, as Einstein would have it, scientific communication should be made as simple as possible, but no simpler. And why is this so important? Schmidt again: "there is a real danger for society’s expectations to get completely out of line with what eventually will prove possible, and it’s important that policies don’t get put in place that are not robust to the real uncertainty in such predictions".
  6. mothincarnate at 10:29 AM on 6 August 2010
    Remember, we’re only human
    Humanity Rules #34 "Contained in this article is the sense that we're on a doomed trajectory ATM. That underlying assumption is wrong." No, contained in this article is the argument that our practices are unsustainable and our impact is exacerbating the problem. "...the sort of thing that this article is against, such as industrialised, modern farming techniques, is the method that most effiently cycles nutrients through the system and generates great yields." The article is not against industrial improvement at all - in fact I make many points that we have achieved amazing things. We need to remain mindful, however, of the ecological services on which we rely. "The problem of limited resourses today is not a natural one but socially imposed." Baseless... Look at peak oil (within the next decade) for an excellent example, however, you should also look into whatever local natural resource management processes you have - almost all will have some form of depletion, largely the using up of resources quicker than they can be regenerated. In other cases, it's that we're changing the process (such as watercourse and landscape use changes) thereby diverting typical ecological pathways. Also, I make no point about population size here. It not a question of the amount of people, but how we manage, how we exploit and how we live. We could, I believe, have 9 billion people and be sustainable - but we cannot live as we currently are. Space,sprawl alone demonstrates this.
  7. Remember, we’re only human
    HR But recycling all locally available nutrients is *exactly* what subsistence farmers need to do. The people who currently have the least resources are the ones who most benefit from getting the most out of what they do have. Those of us in wealthier cities would do well to have a good hard look at approaching peak oil. If the price goes the way it looks that it might, then being a bit more frugal with what goes into landfill may be obligatory if the price of oil-based fertilisers rises as far as it could. Anyone who thinks that consuming less means choosing to have fewer handbags or gadgets should bear in mind it's more likely to mean spending so much on food and transport that those luxuries are unaffordable. There won't be a choice. Either way, sensible use of what we have, whoever we are, makes a better life for ourselves and our neighbours.
  8. Remember, we’re only human
    "1 or 2 dollars a day" means we could increase their income with direct support by an order of magnitude without lifting a finger. We don't choose to do that. We can debate why that may be but it's not a case for some sort of hard physical limit we're up against w/regard to lifting the poor out of poverty.
  9. Communicating climate science in plain English
    Have you seen the format used by ESPERE? Hard to beat the simplicity of 'Basics' and 'Read more'.
  10. Three new studies illustrate significant risks and complications with geoengineering climate
    Thingadonta, what's interesting (to me) about thermal processes of the sort you refer to is their neat fit with sometimes fickle sunshine. It would not really matter exactly when C02 was extracted from the air, just that the average amount over time fit the requirements. If a solar thermal extractor were idle for a week because of inclement weather nobody would be inconvenienced.
  11. Three new studies illustrate significant risks and complications with geoengineering climate
    Why can't C02 be removed from the atmosphere in a manner something like the Haber process? The Haber process removes nitrogen from the air for use as fertiliser. It wasn't an easy process to perfect, and won Haber the noble prize. If huge amounts of energy are required, well, there is- for example in Australia's outback-we have some of the largest uranium deposits in the world, one of the most politically and geologically stable areas, and hardly anyone lives there. Nuclear reactors could be used to drive the removal of c02 from the air. Possible?
  12. HumanityRules at 09:50 AM on 6 August 2010
    Remember, we’re only human
    16 Ned Contained in this article is the sense that we're on a doomed trajectory ATM. That underlying assumption is wrong. 17.adelady at 01:14 AM on 6 August, 2010 "I'm not against doing that in a more enlightened way but we need to be clear that we still have to consume more." I don't understand this. If you need clarification on this I suggest you go speak to a few people living on 1 or 2 dollars a day. The problem I see with the rest of your argument is that the sort of thing that this article is against, such as industrialised, modern farming techniques, is the method that most effiently cycles nutrients through the system and generates great yields. While organic farming may fed the paranoid middle classes, industrialised farming will feed the 6 billion other souls on this planet. 19.John Russell Yep very funny, but I guess you understand that Malthus believed in absolute natural limits. I'm more arrogant in the belief that our huge brains will never allow that to happen. The problem of limited resourses today is not a natural one but socially imposed. 22.Chris G Yep Malthus was wrong. He believed the Isles of Britain could not support more than 7 million people. He was wrong.
  13. mothincarnate at 09:45 AM on 6 August 2010
    Remember, we’re only human
    CBDunkerson "Advances in biotechnology and brain-computer interfaces both have the potential to transform not only our underlying technological infrastructure, but the human race itself. Rather than an upcoming plateau I see entirely new paths to technological advancement opening up." This will require a lot of energy and even more unlikely (as BP, the 1st comment here illustrates) a massive overhaul of how we see ourselves and our moral and ethical systems. Currently most people are still horrified by GM food (I wrote a piece about this a while ago and got into an interesting debate that was as far as I could see a scientific verses ideological debate). Many people are appalled by being (rightfully) titled an animal species. We still have so much dogma and arrogance to overcome before we can be so objective with our investigations to achieve what you point out here. So much so that I suspect we will not reach such a point (Clark often wrote about such a future, and when we look at the scientific breakthroughs, we could be forgiven for jumping on board with his outlook - whoever in retrospect we can see that the sociological constraints make such improvements sluggish unless they prove to be immediately imperative or massively profitable).
  14. Remember, we’re only human
    Muoncounter, I'm thinking in a slightly different way, I think. The relative number of latter-day Einstein analogues is not keeping up with the count of scientists who resemble Einstein in many other ways, have the capacity to have been Einstein. In fact, I'm quite sure there are plenty of people alive today who would have been Einstein (Freddie Fudpucker's Theory of Relativity?) if Einstein had not already grabbed the brass ring that was available only once at a particular level. The ring gets higher each time somebody lays a hand on it, faster than we produce people capable of reaching it.
  15. Remember, we’re only human
    #25: "This apparently nonlinear relationship between important, world-changing insight versus population is intriguing. People today are not more stupid. The fruit we're reaching for is becoming ever higher on the tree" I once heard it this way: If you and I are at a conference and Bill Gates sits down next to us, the average income at our table goes up enormously. But you and I make the same as when we walked in. Same analogy for an Einstein sitting with us. One problem with our species is a form of 'perceptual inertia': We have a hard time perceiving and reacting to things that are slowly changing, even when they are right in front of our eyes. Animals that sense their habitat is under stress will move to more hospitable sites. We just crank up the AC another notch.
  16. 1934 - hottest year on record
    Meehl has quickly responded and sent me a copy of his paper, published last December. Whoops, I stand corrected! I could only find a preprint draft which actually did include the item you quoted, seemed better not to rely on that. As to your last question, if this year is any indication (Moscow, Las Vegas, etc.) Meehl's coauthor seems to be remarking on something visible outside of their work. I can't speak for him but what I'd expect to see is that an overall change in temperature is not going to immediately emerge as a smoothly monotonic increase in global record highs thereby breaking average records year after year but in increasing frequency of excursions in various specific locales. As those point records aggregate and bulk up in relation to broader statistics I'd expect to see much slower movement in the yearly averages, often masked by variability. Taking for instance the case of Moscow we're seeing many contiguous days of temperatures some 25 degrees fahrenheit over norms, but these numbers being folded into a much larger collection of data then will of course in a single year only produce changes at a level of precision we don't look at. Given long enough these changes will work their way up through decimal places and emerge. That's exactly what we see in the global record, variability gradually moving upward. This is something that's amenable to experimentation with a spreadsheet. Folks like Meehl will consider it all old hat but that does not mean you could not have fun with it all.
  17. Three new studies illustrate significant risks and complications with geoengineering climate
    All of these potential 'solutions' seem to require copious amounts of energy to implement -- something that will become more and more in short supply for the foreseeable future. Humans really need to learn to enjoy life without consuming energy. Until we've cracked fusion (or something similar) anything else is disastrous.
  18. Remember, we’re only human
    The Ville #28 In this case thingadonta is correct. Almost every species that has existed during the history of life has gone extinct, and the only known trajectory for a top-of-the-food-chain predator like us is to extinction. Personally I feel that with the human intellect, it may be possible to prevent this to some extent, but with peak oil, population overshoot, and climate change being pretty pressing concerns the crunch time to deal with it is aproximately now.
  19. It's cooling
    Chris, thanks for the references. Upwelling is an interesting mechanism. It would seem like it should leave footprints, though. The cold water would have to absorb sunlight near the surface and become relatively warmer before it was driven down, and that warmer water would have to escape detection.
  20. mothincarnate at 07:58 AM on 6 August 2010
    Remember, we’re only human
    Arkadiusz Semczyszak I've done, and will do much much more posts, regarding ecological loss with climate change. You may have regional examples where local climate fluctuates a fair amount and the species handle the change well. As I state in the article, insect species at higher latitudes are likely to fair better than their lower latitude counterparts - they have more room. That said, the fossil record tells us that climate change relates to increased extinction rate, decreasing ocean pH increases extinction rate and we know that our modification of landscapes increases extinction rate. We know we the cause of all these impacts and we also know that we rely on numerous ecological services. Using ideal regional examples does nothing but send us further up the river without a paddle.
  21. Remember, we’re only human
    thingadonta: "Part of the reason we live in cities is because nature is cruel, unfair, dirty, disease ridden, dangerous, unsafe, murderous, extinction ridden, forever competing, destroying, dispensing, exploiting, etc." extinction ridden?? How many extinctions are caused by non-human intervention? The only thing I can think of is volcanoes or something similar. thingadonta: We have learned to reject that within nature which we deem inconsistent with our human values, and there are plenty of them. Really. Just how many people do you speak for? Yourself? And your personal views about nature? What exactly do we reject? Or is this some religious view? eg. anti-gay or something?
  22. Cornelius Breadbasket at 07:46 AM on 6 August 2010
    Why I care about climate change
    #97 kdkd Thanks for that. Re reading my post about the UK it sounds horribly arrogant (well I am a limey/pommy). Apologies. The political landscape you describe of Australia sounds remarkably similar to the UK - except you have the greens where we have the Liberal Democrats. I think I'll emigrate to Australia... We get a lot of news in the UK about extreme weather events in Australia (droughts, floods, wildfires, sandstorms). Are these acting as a driver for action on carbon reduction? You must have a strong denier community too - otherwise Monckton would never have visited. But there are so many excellent communicators in Australia - Tony Jones magnificent debunking of Martin Durkin (http://www.youtube.com/watch?v=goDsc9IaSQ8) Potholer54 (http://www.youtube.com/user/potholer54) and of course this wonderful site. Is there a trend away from denial in Australia?
    Response: "Is there a trend away from denial in Australia?"

    It's difficult when the leader of the opposition, who is a few marginal seats away from becoming leader of our country in a few weeks, states that "climate change is absolute crap". A few months ago, he urged primary school students to be skeptical about the human influence on climate change because it was warmer ''at the time of Julius Caesar and Jesus of Nazareth''.
  23. 1934 - hottest year on record
    Meehl has quickly responded and sent me a copy of his paper, published last December. He wrote this: "We chose 1950 as the starting point because we needed a significant number of US stations with nearly continuous daily temperature measurements. Prior to 1950 the data quality falls off at many stations and there are a lot more missing daily temperatures thus making those stations not usable in our study." The new NCDC and old Weather Bureau records are, of course, monthly with the yearly averages being derived from each. Meehl's co-author said this about their work: "But as the average temperatures continue to rise this century, we will keep setting more record highs." Why shouldn't that apply to the yearly averages derived from monthly data since the northern hemisphere has been rising?
  24. 1934 - hottest year on record
    Broadlands, again, you're not getting a very simple point here. At any temperature station record highs and lows will be distributed in a skewed way, with most appearing nearer to the -beginning- of the station history. You're also missing the notion that later records are more significant. The first record is automatic, the second a little less likely, etc. until once you're into decades of station history new records are both infrequent and represent more unusual excursions. Try setting up a thermometer in the shade at your house w/a tabula rasa record and record local record temperatures and the phenomenon will be easily visible. As to Meehl's selection of the date range, the article is still in press so you're not likely to get a response of any kind until his paper has been published.
  25. Three new studies illustrate significant risks and complications with geoengineering climate
    CBW: I think you've hit the nail on the head there. Who will oversee the geo-engineering... if we can't get global agreement on reducing emissions, how are we going to get agreement on an organisation to change the weather? And if we do create an organisation to carry out geo-engineering how do we stop it getting sued? Where I see a huge problem is in deciding what geo-engineering to carry out, because it will inevitably involve models. Given that the deniers are so anti-models, how can they support geo-engineering?
  26. Remember, we’re only human
    #4: "we live in cities is because nature is cruel, unfair, dirty, disease ridden, dangerous, unsafe, murderous, extinction ridden, forever competing, destroying, dispensing, exploiting, etc." I've lived in cities that are described in exactly the same way. Not to mention foul air, traffic, noise and heat.
  27. 1934 - hottest year on record
    Doug... Thanks. I did write to them, back on June 9th. So far, no reply. Maybe you can do better? But, if you do write be careful to ask which of their two averages one should use. There are two for each year... one can be derived from summing the individual states and averaging them as I did for the comparable individual Weather Bureau states. This average differs from their own 48 state average. They argue that the former should not be used because "a simple arithmetic mean is not appropriate". ?? The latter are more appropriate having been state re-weighted... Montana is bigger than Delaware? But, either way, both are consistently lower than the original "raw" weighted Weather Bureau values. More "up-to-date" but very confusing. Three different monthly averages for the year, each lower than the other? I will try to learn from Meehl's (not Meehle) expertise but I'm a bit reluctant to simply accept the conclusions of a study that left out 50 years worth of record high monthly temperatures in 30 states... that's almost two-thirds of the contiguous US. Also, 80% of the record lows occurred before 1950... most in 1917. I've written to Dr. Meehl about why he chose to start his study in 1950.
  28. Remember, we’re only human
    On the other hand I can be quoted as foolishly saying to my family that the television game "Jeopardy" won't be played by computers at a human level for another 30 years. Turns out IBM now has a machine that plays very competitively at the expert level. That's a pretty huge accomplishment even though it did not depend on any particular leap of insight, rather was a meticulous integration task. Hmmm.
  29. Remember, we’re only human
    One other thing to ponder. Comb through various lists of "world's greatest scientists" and you'll see a feature of what might be termed as diminishing returns. Most of those we consider to be intellectual luminaries and who produced fundamental insights leading to a myriad of less profoundly significant explorations lived at or before the point where world population was 2 billion persons. The subsequent growth to 7 billions and beyond appears to be producing ever-fewer Einsteins and the like, despite our better facilities for intellectual growth. This apparently nonlinear relationship between important, world-changing insight versus population is intriguing. People today are not more stupid. The fruit we're reaching for is becoming ever higher on the tree is one possible conclusion.
  30. Remember, we’re only human
    Doug, you may be right... but I doubt it. The article at the top tells us to remember that we're only human... by the year 2100 I highly doubt that will be the case. Advances in biotechnology and brain-computer interfaces both have the potential to transform not only our underlying technological infrastructure, but the human race itself. Rather than an upcoming plateau I see entirely new paths to technological advancement opening up.
  31. Remember, we’re only human
    I'll play devil's advocate for a moment w/regard to upcoming technology. Our confidence in technological strides being a more or less continuous and boundless prospect may be a warped perspective. For the past few hundred years we've enjoyed the fruit of a rather instantaneous explosion of basic scientific insight as well as sudden progress in mathematics. These intellectual leaps opened a void of potential technologies which we've steadily filled; the first and easiest hurdles of intellect once crossed lowered the slope of technological progress. As well, we've had the benefit of hydrocarbons unleashing staggering amounts of energy to do things that are unlikely without copious joules being available. We've become so accustomed to this flood of energy that it's become strangely invisible to us; we swim in energy like fishes swim in the ocean. A huge proportion of what we proudly point to as progress is stretched thinly over a balloon of ergs. Ahead we face a scenario where intellectual progress is more difficult, where putting very simple physics and coal together will not yield a Newcomen engine, where getting from the Newcomen engine to the Watt engine is not going to be an easy leap. The easy strides are over but we're still basking in the glow of accomplishment. Thinking ahead, we're applying our past experience with filling a vacuum of opportunity with copious physical and energy resources to a future where opportunities are smaller and resources more scarce. As an example, there are some promising developments in nanotechnology applications to photovoltaic panels emerging but these are little steps being carved out of an increasingly steep hill. I think it's possible we'll arrive at a ledge on what has become a precipice past which further progress is extraordinarily difficult, failing some kind of avalanche of understanding of the kind we saw leading up to the 20th century. Whatever the insight may be, it won't have the long lever of fossil fuels to help shift it into a useful position.
  32. Remember, we’re only human
    Malthus, wrong. Hmm, do the conditions described by Malthus exist nowhere in the world? It would probably be a mistake to think that some critical point would come everywhere at once. With BAU, limited resources and no limit on population, it is only a question of 'when' and 'where', not really 'if'.
  33. Remember, we’re only human
    Saying 'Malthus' got it wrong is oversimplifying... but so is saying that population growth will lead to resources running out by date XYZ. The problem is with assumptions that the current paradigm will remain valid well into the future. The pace of technological change has shown us repeatedly that this is a sucker's bet. Chances are that by the time we get to 9 billion people we'll be using technologies we haven't even imagined yet. Doubtless it won't be a seamless transition... any more than the rise of modern agriculture FULLY prevented the kinds of famine events Malthus predicted. Mostly yes, but not entirely. It would be reckless to assume that technologies which can save us WILL come along, but it is equally unreasonable to insist that they won't. We don't know yet. Which is a terrible situation to be in... because if you assume future populations will be limited to current technology you may find yourself justifying draconian emergency measures (e.g. quotas on how many kids people can have) that may turn out to have been unnecessary, but if you assume that future technology will save the day and it DOESN'T then you've got massive suffering. A middle course would seem prudent. Do enough to stave off catastrophe in the short to mid term and hope for technological improvements to avoid the problem without drastic measures in the long run. Rather like what has been proposed (though not yet enacted) with CO2 reductions to stave off global warming.
  34. Waste heat vs greenhouse warming
    RSVP at 14:21 PM on 5 August, 2010 Not strange RSVP, so long as one doesn't leave out both the absorptive properties of greenhouse gases, and their spherically-averaged radiative properties. Then the Wikipedia and our explanations are entirely compatible. A comparison of a "naked Earth", with an Earth surrounded by an atmosphere containing greenhouse gases might help to overcome your apparent paradox: (i) a "naked earth" (no atmospheric greenhouse gas). The solar radiation warms the surface which radiates LWIR. Since there is no atmospheric absorption of LWIR this emitted radiation travels freely to space. Thus the maintenance of radiative equilibrium (with incoming solar) is achieved by emission from the surface. The flux of LWIR required to balance the incoming solar flux is reached by a surface temperature of around 255K (taking into account earth surface albedo). That's the surface temperature of a "naked earth". (ii) Now we add LWIR-absorbing atmospheric gases which captures the LWIR and either reradiates (spherical distribution) or transmits the vibrational energy to other atmospheric gases by molecular collisions, warming these. Clearly for radiative equilibrium to be maintained the radiative flux must still balance the incoming solar radiation. However the photons radiated to space to achieve this are now emitted from an altitude that is higher, on average, than the surface, and thus colder. In order to generate sufficient radiative flux these regions must warm up. All the atmospheric layers right down to the surface warm up too. Everyone on the surface is warm and happy!
  35. Grappling With Change: London and the River Thames
    Dorlomin going east indeed problems become larger, avenues for flood management system failure become more numerous as you suggest. We also run into an interesting case where even the British with their keen and fanatical thinking and planning skills are challenged by their human nature. There's enormous pressure to intensify development outside of the GLA, toward the estuary and into land that's been ignored 'til now. Many "brownfield" sites with heavy pollution can be developed if they're cleaned up, or developers can move into other land that while cleaner and cheaper to build on is at distinctly higher risk from flooding. A large public policy dilemma, once which I couldn't tackle in the already-bloated writeup on the GLA. I ran into many references to this officially sanctioned grand scheme (which of course has a grand name too, can't remember it now). Suffice to say, if folks decide to purchase properties in the envisioned new development east of London they should also consider hip waders; the government clearly is leaning toward the euphemistic "resiliency" in that area. By the way, I was needless personal about HR in a remark upthread about nurturing doubt. This is probably because of lingering frustration on my part over the failure of any useful climate change output on the part of our legislators in the U.S., where experts in the political realm have managed to paralyze our ability to deal with facts, exactly the sort of infection I speak of in the post above. Our House passed an imperfect package of legislation that would nonetheless have offered some utility in dealing with C02. Most importantly, if this legislation had survived the increasingly bizarre filibuster hurdle in our Senate we would finally have provided the kind of clear signal the rest of the world seems to be waiting for. Edge-effects count more and more here in the U.S. and the filibuster proved remarkably useful to a minority unable or unwilling to confront facts. Though research shows relatively few people can't believe science, these few are stopping progress. Hence my frustration with what is a psychological problem. HR has a thick skin but all the same I'm sorry I personalized my remarks.
  36. It's cooling
    TomJones at 03:01 AM on 6 August, 2010 Not sure I understand your argument Tom, since the observed increase in deep ocean heat (e.g. [*]) doeesn't require that this bypasses the surface. For example we know that during La Nina years there is a shift in the location of the thermocline in the Pacific with enhanced upwelling of deep cold waters. This will have the effect of transferring heat from warmer waters above the thermocline to the deeper oceans. Likewise there is increasing evidence on some of the mechanisms by which thermal energy can be transferred to deeper ocean waters in a warming world [**] There's nothing surprising about this. The oceans must warm in the response to radiative forcing. [*] the work of Greg Johnson and his collaborators is a good starting point; e.g.: Johnson GC et al. (2006) Recent western South Atlantic bottom water warming Geophys. Res. Lett. 33, L14614 Johnson GC et al. (2007) Recent bottom water warming in the Pacific Ocean J. Climate 20, 5365-5375. Johnson GC (2008) Warming and Freshening in the Abyssal Southeastern Indian Ocean J. Climate 21, 5351-5363. Ozaki H et al. (2009) Long-term bottom water warming in the north Ross Sea J. Oceanograph. 65, 235-244. Johnson GC et al. (2009) Deep Caribbean Sea warming Deep Sea Research. 1 –Oceanograph. Res. 56, 827-834. Johnson GC (2008) Reduced Antarctic meridional overturning circulation reaches the North Atlantic Ocean Geophys. Res. Lett. 35, L22601 [**] e.g. S. Masuda et al. (2010) Simulated Rapid Warming of Abyssal North Pacific Waters Science 329, 319 - 322
  37. Remember, we’re only human
    Humanity Rules, #13, It is surely the height of hubris to boast that "The Greeks and Romans got it wrong 2000 years ago". Who ever got it right? Rome existed as a state and an empire for much longer than most modern states have existed, including the United States. Greece enjoyed a long silver age as the Byzantine Empire, longer than the United States has existed. Huxley and Orwell got it "wrong" only in so far as their works of art focussed on exaggerating particular trends in society. No one says that "Picasso got it wrong in Guernica". Both wrote their books as warnings, and they were pretty damn good ones. We do have the first world civilization in history, but it is no point in pretending it is not vulnerable - to nuclear attack, to internal revolution, to a new strain of disease, environmental decay or climatic shift. The main difference from the Romans is that the mass of people have come confidence in receiving their next 9 meals. It is said that every civilization is only 9 meals away from collapse, because no society can survive if hunger persists beyond that point. No doubt at some point Romans shrugged "Barbarians? Who cares?". Our civilization needs to be cognisant of threats and prepare for them. Lack of resources (food, medicine) face only the very poor on the globe. If by some consuming less, others receiving the wherewithal to consume more, our world civilization would become more stable and more secure, than why not?
  38. Remember, we’re only human
    HumanityRules at 23:34 PM on 5 August, 2010 I gave a wry laugh when I read your words... "Malthus got it wrong 300 years ago..." Followed soon after by your comment, "The unfortunate fact is that lack of resourses is still the greatest problem facing us all." Oh, the irony!
  39. Remember, we’re only human
    Following on from John Chapman's comment, this might be a useful time to introduce this information which I was sent the other day. It's a tough subject to raise -- the voice of experience -- but if humans don't tackle the fact that nine billion people* puts an unimaginable strain on our environment, the vast majority of our offspring face a catastrophic future. Discuss. [*9bn is the figure the world population the UN projects for 2050]
  40. Confidence in climate forecasts
    Ken Lambert at 23:55 PM on 5 August, 2010 "Put all that together and you get a climate sensitivity of between 0.75 and 4.5 degC for doubling of CO2 to 560ppmv, depending on whether you read Lindzen or Hansen." Ken, it sounds a little like you consider the climate sensitivity is a matter of choice! In fact the science is a far better source for understanding the likely degree of surface warming in response to massively enhanced greenhouse gas concentrations. This indicates that the range of likelihood is between 2 - 4.5 oC (per doubling of [CO2]), which is quite well constrained at the low end (little likelihood of climate sensitivity below 2 oC[*]), but poorly constrained at the high end (poor basis for rejecting higher climate sensitivities). See for example Knutti and Hegerl’s recent review. R. Knutti and G. C. Hegerl (2008) The equilibrium sensitivity of the Earth's temperature to radiation changes Nature Geoscience 1, 735-743 In reality it is very difficult to envisage that the climate sensitivity (equilibrium surface warming from a radiative forcing equivalent to doubling of atmospheric [CO2]) can be below 2 oC (e.g. [*]). Lindzen's efforts to insinuate a low climate sensitivity are dismally flawed [**] (if not worse [***]) and one really does need to play at disregarding a huge body of science, to consider that his analyses have scientific merit. [**] Murphy, D. M. (2010), Constraining climate sensitivity with linear fits to outgoing radiation Geophys. Res. Lett., 37, L09704 Chung, E.-S., B. J. Soden, and B.-J. Sohn (2010), Revisiting the determination of climate sensitivity from relationships between surface temperature and radiative fluxes Geophys. Res. Lett., 37 L10703 [***] Trenberth, K. E., J. T. Fasullo, C. O'Dell, and T. Wong (2010) Relationships between tropical sea surface temperature and top-of-atmosphere radiation Geophys. Res. Lett., 37, L03702 ”…particularly OHC which is the least best measured, looking dodgy and will be the final arbiter of warming extent.” The “final arbiter of warming extent “ is surely the warming extent Ken. We live at the Earth surface and it is the surface warming that is of interest. The climate sensitivity is explicitly defined in relation to Earth surface warming. Most of our understanding of past climatology that informs us on the relationships between enhanced greenhouse forcing and Earth response relates to earth surface responses. We can play the game of selecting arenas of uncertainty (OHC) in order to attempt to ramp up the impression of uncertainties, but one wonders why anyone would think that sort of game fruitful! Not so distant history warns us of the dangers of that sort of misrepresentation of scientific knowledge. ------------------------------------------------------- [*] For example, the Earth has warmed by around 0.8-0.9 oC since the middle of the 19th century, while [CO2] has risen from around 286 ppm then to 388 ppm now. A climate sensitivity of 2 oC should then give an equilibrium warming of: ln(388/286)*2/ln(2) = 0.86 oC We know that we haven’t had the full warming from this enhancement of greenhouse gases, since it takes the earth many decades to come to equilibrium with the current forcing resulting from raised greenhouse gases. Likewise we know that a significant part of the warming from this enhancement of greenhouse gas levels has been offset by manmade atmospheric aerosols. On the other hand some of the warming is due to non-CO2 sources (man-made methane, nitrous oxides, tropospheric ozone, black carbon). Non greenhouse gas contributions to this warming (solar, volcanic) are known to be small. Overall, it’s rather unlikely, given the warming since the mid-19th century, that climate sensitivity is less than 2 oC. This is expanded on in more detail in Knutti and Hegerl (see above), in Murphy et al. (2009), in Rind and Lean, 2008, in Hansen et al (2005), etc. etc.
  41. It's cooling
    Can anyone suggest a mechanism by which greenhouse warming bypasses the atmosphere, bypasses the upper 700 m of ocean, and warms the ocean between 700 and 2000 m? This seems like it will be required for the earth to continue warming.
  42. gallopingcamel at 02:56 AM on 6 August 2010
    Grappling With Change: London and the River Thames
    doug_bostrom, My reservations have to do with the various statements made about the rate of sea level rise. For example those made by the IPCC, Rahmsdorf, Rohling et al. This was not the central theme of your presentation and we are already discussing it elsewhere: http://www.skepticalscience.com/Confidence-in-climate-forecasts.html#20509
  43. It's cooling
    Response: Levitus' data covers only the upper ocean heat which shows more variability than the total ocean heat. Measurements of ocean heat down to 2000 metres deep show that the oceans are still accumulating heat. Would you please cite a source for that statement? I am unable to find such a measurement and following the link only dumps you back at this site. The NODC data shows a suggestive resemblance to atmospheric temperature data, delayed a few years.
    Response: The source is von Schuckmann 2009:


    Figure 2: Time series of global mean heat storage (0–2000 m), measured in 108 Joules per square metre.
  44. Three new studies illustrate significant risks and complications with geoengineering climate
    I think the potential political fallout of these kinds of geoengineering are grossly underestimated. (To say nothing of the eventual political fallout of AGW, in general.) What happens if China decides to start pumping SO2 into the stratosphere and it dries out the US midwest? Or if the US starts doing it, and it causes massive flooding in China or India? There are a large number of destabilizing scenarios, and political leaders are always happy to blame someone else for the problems in their country. If the situation deteriorates, you get military strikes on the suspect facilities, and it escalates from there. Sure, a nuclear war would result in global cooling, and reduced carbon emissions from industry, but I don't think it would be in civilization's best interest.
  45. Remember, we’re only human
    "I'm not against doing that in a more enlightened way but we need to be clear that we still have to consume more." I don't understand this. If we take farming and gardening as models for other activities, we know that it's not a matter of taking stuff from the soil to make other stuff to consume. All the atoms, molecules, building blocks we will ever have are already in the system. Fertility is not a function of maximum extraction of nutrients and other substances. Fertility is a function of how rapidly we can get those atoms and molecules cycling through that system to benefit all who might feed from it. So we don't throw organic waste into landfill or elsewhere where it might be lost to the system for a long time. We put it where it will do the most good straight away - back into the system of reproducing more organic materials. And the same can be said for most economic and other processes. Money is most valuable when it is working - to enhance the material wellbeing of all who are involved in its various transactions through a society. Technology can always be used better and its use and development can create better technologies. I do not see where this fear of loss of some mysterious quality of life comes from. Unless the world is comprised entirely of elderly weirdos clinging to their mouldering stacks of 30 year old newspapers, the idea is just silly.
  46. It's the sun
    GnDoty, that's a good question. The appropriate thread for it is It’s not bad.
  47. Dikran Marsupial at 00:59 AM on 6 August 2010
    It's the sun
    GnDoty The polar ice caps had melted in many of those warmer periods, which means that the oceans were several tens of meters higher than they are now. Of course that wouldn't be a problem would it? ;o) The point is that our agriculture and civilisation has adatped to suit a particular climate. If the climate changes then we have to adapt our agricultre, which can only be done at a cost; a cost that a large proportion of the Earth's population cannot afford (as they are already at subsitence level or worse). Even if overall productivity goes up, that doesn't mean that it will go up everywhere, so what happens to the countries that find because of first world use of fossil fuels their country can no longer support its population? That wouldn't be a bad scenario perhaps for someone who wanted a world government that oversaw the redistribution of wealth to make sure everyone got enough of that food to live on, but I don't think that would be everybodys cup of tea! In short, the change is a problem, regardless of the eventual destination. There is also a risk the destination will be bad in its own right, but it doesn't have to be for climate change to be a problem worth trying to avoid.
  48. It's the sun
    Considering previous time periods with higher concentrations of CO2, I have a few questions. During these times (pick any period) we see larger, widespread plant life. This plethora of vegetation leads to larger animals (dinosaurs). Could someone explain how more plant life due to increased CO2 levels - which provides more food for animals - is a bad scenario? If animal life has benefitted from increased CO2 levels in the past, why is there a negative reaction to increases in CO2 in our current time period? It's assumed that common knowledge of ice age periods lead to a reduction in biological populations. Should this be the real fear instead of warming?
    Response: The difference between the past and now is the sun was much cooler in past periods of high CO2. Currently, we're heading towards high CO2 and high solar output. As it gets hotter, drought severity increases (it's been increasing over the last century). This has a significant impact on plant growth and agriculture.

    As for the fear of an impending ice age, so long as you don't see a huge ice sheet creeping down over Canada, you can rest assured.
  49. Dikran Marsupial at 00:28 AM on 6 August 2010
    On Consensus
    Arkadiusz Semczyszak said "And what about the detritus Tundra?" Again, you are missing the point. The observations show beyond reasonable doubt that the natural environment as a whole is a net carbon sink, and therefore is opposing the rise in atmospheric CO2, not causing it. It is irrellevant if soil respiration is increasing if some sink elsewhere in the natural carbon cycle is strengthening sufficiently to take up the extra carbon from soil respiration (the observations show that this must be ocurring - even if we don't know the detail of exactly where the carbon is taken up). You have to look at the big picture. So, if the natural environment is the cause of the observed rise in atmospheric CO2, why is the observed rise smaller than anthropogenic emissions. If you can't answer that question, maybe it will help you to understand why increased soil respiration does not (by itself) imply doubt on whether the rise is of anthropogenic origin.
  50. Confidence in climate forecasts
    More broadly, Ken, my impression of your comments here is that you always raise the issue of uncertainty, and then use that to imply that it means that things might be better than the standard consensus. But they might also be worse! A very low climate sensitivity implies the existence of large negative feedbacks (planetary homeostasis, a la Daisyworld or Lindzen's "iris") that somehow keep the climate within a nice cosy range. It's hard to see how that squares with the existence of glacial/interglacial cycles!

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