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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 108551 to 108600:

  1. Climate Change: Past, Present, and Future
    #17: "WUWT posts are much more sophisticated and subtle than a lot of its readership." What kind of readership does Skeptical Science have? A bunch of people beating their chests, rehashing the same stuff over and over, trying to demonstrate who's most clever? I would venture that 99.94% of skeptics don't have a degree in earth sciences or related areas, and would have trouble following most of these discussions. I thought Skeptical Science was intended to educate those 99.94% of skeptics, but the ones I've interacted with stay about 30 seconds and delete the page. That's not going to help solve our worsening climate change problems. Skeptical Science should serve the congregation, not the choir.
  2. Climate Change: Past, Present, and Future
    #16:"is allowed" I don't quite understand what you're getting at here; where's the discussion of allowing this and prohibiting that? However, there are intelligent choices that can be made regarding food consumption.
  3. We're coming out of the Little Ice Age
    "Er, no. Not even remotely. Did you miss this graph?" I can see it. I meant 1365. The graph is mostly under 1365, on average from about 800 AD to almost 1900 AD. from During the LIA it was averaging about 1364.75. Even the minimum around 1975 was higher than anything the previous 100 years.
  4. Climate Change: Past, Present, and Future
    Doug @ 14 Really, the so-called sceptical/AWG divide when you look at the output of mainstream contenders is akin to the two religious sects of Lilliputians who are divided between those who prefer cracking open their soft-boiled eggs from the little end, and those who prefer the big end. WUWT for example has of late put a fair bit of very conventional science into play much of which would pass without raising eyebrows if posted here and presented as coming from a 'warmist' source. WUWT posts are much more sophisticated and subtle than a lot of its readership.
  5. Climate Change: Past, Present, and Future
    #15, if breathing is allowed without eating food that has a carbon footprint, then I agree.
  6. Blog review of scientific coherence
    Contrarians are coherent and consistent in one respect: Significant efforts to reduce greenhouse gas emissions are bad. Since nearly all global warming contrarianism stems from ideological fear of government, and the science implies some significant government action to solve the problem, one that involves significant greenhouse gas reductions, then they absolutely have to be consistent on that. If their skepticism of the science was genuine, one would think a few might not be so vehemently opposed to greenhouse gas reductions, because doing so would result in a much cleaner environment and a sustainable energy future. I haven't really observed this, though. In supporting the hypothesis that reducing greenhouse gases emissions is bad, there are a variety of ways to go about it, many of them contradictory, which brings us to this nice post and excellent site.
  7. Climate Change: Past, Present, and Future
    #12: "why are we still allowed to breathe" Breathing was discussed here. I don't want to presume that there was a consensus, nor speak for one, but at least some folks said something to the effect of "Don't hold your breath."
  8. Climate Change: Past, Present, and Future
    Dangerously reasonable, even heretical in some circles, Chris. (3) is dubiously relevant given that we seem to have introduced a durable secular trend in energy retention. (4) relies on past as prologue; the past did not include what's happening in the present so anachronisms are a questionable means of discounting our influence. Past those points, I'm not sure what you're describing is really skepticism about science as much as it is worry over human nature. We do have many examples of how our nature has led us to underestimate our impact on the various systems surrounding us, which we more or less depend on to continue thriving. The body of evidence we have available suggests we've made some serious mistakes in the past and should be forewarned about scaling up those errors.
  9. Does Climate Change Really Matter?
    This WMO summary of the summer of 2010 makes delightful reading. Climate extremes have always existed, but all the events cited above compare with, or exceed in intensity, duration or geographical extent, the previous largest historical events. ... The occurrence of all these events at almost the same time raises questions about their possible linkages to the predicted increase in intensity and frequency of extreme events, for example, as stipulated in the IPCC Fourth Assessment Report published in 2007. The Report stated that “…the type, frequency and intensity of extreme events are expected to change as Earth’s climate changes, and these changes could occur even with relatively small mean climate changes. They go on to mention Stott, Stone and Allen 2004 Human contribution to the European heatwave of 2003: it is very likely (confidence level >90%) that human influence has at least doubled the risk of a heatwave Does it really matter?
  10. Climate Change: Past, Present, and Future
    The current mainstream [ie, non-feral :-)]sceptical position at least as I understand it could be summed up as follows: 1) CO2 has been rising 2) Temperatures have been rising 3) (1) very likely has made a substantial but not exclusive contribution to (2) But 4) We're not as confident that temperature rise is unprecedented - ie, we have some doubts about the palaeoclimate proxy record when it is 'spliced' onto the modern record 5) We don't want to overlook the role of other feedbacks which may be important whether as exacerbating or mitigating factors 6)We're not as confident of catastrophic outcomes even if temperatures and CO2 rises more or less as projected 7)Even if our reservations in (4),(5), and (6) prove to be correct, becoming much less dependent on fossil fuel and decarbonising our economies and our emissions is a very good idea anyway for lots of other reasons. 8)However, we're much more likely succeed at (7) if we avoid a panicky response and scare the proverbial horses whilst triggering the laws of unintended consequences.
  11. Climate Change: Past, Present, and Future
    If it's any consolation, U.S. debt next year will exceed its GDP, and many countries are sure to stop loaning us money so that we can continue to buy oil and gas. Peak Oil, just over the horizon, promises to be another damper. (Or is Peak Oil just another one of those myths?) In any event, a 15 billion world population would be impossible, because the land can barely support the population we currently have, even when using fossil fuel-based fertilizers. Gas production in many countries has also peaked, and fertilizers are becoming more difficult and expensive to come by. Without artificial fertilizers, world food production will drop sharply. So even the 8.7 billion population is questionable. And why are we still allowed to breathe, while holding CO2 production constant? Suppose the world has 6 billion people consuming 1000 Kilocalories per day. That equates to 6 trillion kilocalories per day. Modern food production and transportation processes consume about 7 kilocalories of fossil fuel per kilocalorie of food we consume. Thus modern food production and transportation would consume about 42 trillion kilocalories of fossil fuel per day. If we stopped modern food production and transportation, most of us would die, so I suppose we would not breathe or contribute CO2.
  12. Blog review of scientific coherence
    Classic red queen disease and before breakfast too, all in one confused head.
  13. Video update on Arctic sea ice in 2010
    Ever heard of Charlie Brown, Lucy, and the football, Adrian?
  14. Video update on Arctic sea ice in 2010
    Has anyone seen how fast the ice is growing back in the last little while looks like a long cold winter,especially with UHA showing near sea level cooling of 100th of a degree per day for the last little while.
  15. The Phony War: Lies, Damn Lies and the IPCC
    @CW: "I haven't written anything about radiative forcing." You consider the current warming to be insignificant, as your next chapter summarizes. "All I'm doing is pointing out that the extent of a warming rate is low as declared by the IPCC" That's a strange interpretation. The fact it is in the lower scenario doesn't mean it's "low" (as in not significant). A 1.8C/century trend is very high compared to past climate change. You're trying to play on words, here. Please keep it honest. "by daily, annual, and millenial scales of change, not particularly significant." It is in fact quite significant, because it cannot be attributed to natural cycles (unlike the HCO) and is almost certainly due to CO2, which means temperatures will keep on rising, and the oceans will continue to acidify. "I would gladly like to see any evidence you can provide otherwise." I would gladly like to see any evidence that supports *your* claim, seeing as it goes against the established science. "No. See figure 1" That's one paper. This one argues the heat was 0.2 to 0.6 above: "The early to mid‐Holocene appears as a relatively long warm interval some 0.2–0.6 K above present‐day temperatures, the culmination of the warming that followed the end of the last glaciation" In any case, I'm glad to hear you admit the MWP was 0.5 degrees colder than the current temperatures. For my part, I'll say it's possible the holocene was warmer, but as the change occured over a long period of time (and the current projected increase will take us above the warmest HCO estimates before 2050) it is useless to compare it to the present situation, especially when we know the causes aren't the same.
  16. Climate Change: Past, Present, and Future
    Miekol @2 Your analogy to proving the existance of God is faulty. A God by definition is an unknowable phenomenon. We might postulate that one exists or not but the nature of the postulate is of the existence of a phenomena that has absolutely no physical interaction with the physical universe that we could observe, even less interactions that we could make predictions about EXPECTED physical phenomena. Greenhouse effect and AGW is very much a case of of a postulate that observable physical phenomena WILL occur. One core expected phenomena are changes in the emitted radiation spectrum for the planet from what otherwise would be the case due to the GH effect of these gases. And that this change to the spectrum will vary over time as the amounts of GH gases changes. Expected observable phenomena. What scientists would call a 'falsifiable' prediction. If we expect this phenomena and we don't see it, whoopsy we have a problem. If we see the phenomena then strong support for the postulate. And both expected phenomena are directly observed from satellite, high altitude aircraft and ground based observations, and have been for years. Not just theory. Direct observation And since that emission spectrumrepresents the energy flow from the planet, we are directly observing changes in the energy balance. We are directly observing a phenomena that is changing the energy balance of the planet. Take an analogy. If I put a pot of water onto the stove top and turn on the heat, and I have instruments that allow me to observe the heat flowing through the steel of the pot, I can make a reasonable conclusion that this heat flow will then continue into the water and heat it. By your reasoning if we observe the heat flowing through the steel and observe the water heating, we cannot assume that the heat from the steel is the cause. Something else might be heating the water. While there may be other sources of heat going into the water as well, we might be holding a flame to the top of the water at the same time, to assume that the heat flow through the steel will not have any effect on the water is nonsensical. Coming back to AGW. We know there is a radiation imbalance, we can see it. We know it is large enough to explain the observed warming. Other processes have been put forward that may contribute as well, but everything we know about them says they are not of anything like the same magnitude - see the recent post on Galactic Cosmic Rays at this site for a discussion of one of these areas. The only way we can say that we have a very strong understanding of why the phenomena should occur, we have observations of the phenomena occurring, but then say the consequence of the phenomena, heating of the planet may not be caused by the phenomena is if we assume that the Law of Conservation of Energy is wrong. If that is true Miekol, DUCK! The universe is about to self destruct.
  17. Climate Change: Past, Present, and Future
    That is way cool Rob...I'm hoping to replace our Prius with an EV....
  18. New temperature reconstruction vindicates ...
    Johnd @67, OK, downloaded the paper. The Ljungqvist reconstruction runs from 1 AD through 1999 AD, and the calibration period was 1850-1989.
  19. Climate Change: Past, Present, and Future
    Albatross... I've actually used that very same video to turn a few skeptics into believers. The other one that always seems to get skeptics thinking is the electric dragster video.
  20. New temperature reconstruction vindicates ...
    Johnd, helps to remember that researchers in the topic are not primarily invested in policy outcomes, obsessive scrutiny of 12 year old papers, etc. Life moves on, there are new things to investigate. There's also the matter of money. Who's going to pay for repeating the research? The iconic Keeling lost his Antarctic sample continuity due to funding cuts.
  21. Climate Change: Past, Present, and Future
    Bamboozled @7, Was it this one?
  22. Climate Change: Past, Present, and Future
    I saw an interesting experiment/demonstration a while ago that rather neatly demonstrates to the dis-believers why CO2 causing warming is more than just a theory: Have a glass cylinder about e.g. a metre long and e.g. 10 cm diameter. At one end of it (outside the cylinder) put a candle or other heat source. At the other end (also outside the cylinder) put a thermal camera, pointing at the candle. On the camera's display, the candle should show up perfectly. Now fill the cylinder with CO2. You'll still be able to see the candle, but the IR camera will not. This proves that CO2 acts as blanket over the atmosphere - energy can still get to the surface as short wavelength light, but the longer wavelength IR radiation can't escape back out into space. I'm not sure where I saw it now. I've just checked on youtube and am unable to find it. Maybe someone who is better at writing and a little more scientifically literate than me can turn my summary into a simple demonstration? It seems to me that it is an approach that is not often tried: instead of using historical data (which people refuse to believe or say that it's just a coincidence), how about demonstrating the mechanics in a repeatable way?
  23. New temperature reconstruction vindicates ...
    Albatross at 08:19 AM, thanks I missed that early comment and only had the abstract to go on. However I am still not clear where the reconstruction ends and left wondering what proxies could provide data for all but the last couple of decades. Surely for the sake on continuity and validation of the proxies themselves, the same data should be continued to be progressively collected as time moves forward.
  24. New temperature reconstruction vindicates ...
    Johnd I think that we are getting our wires crossed. The authors are quoted @4 saying: "The proxy reconstruction itself does not show such an unprecedented warming but we must consider that only a few records used in the reconstruction extend into the 1990s." So the reconstruction (base don limited proxies) goes into the 90s. From the figures shown here, their reconstruction seems to compare very well with the thermometers over the remainder of the instrumented record before the 90s.. I do not know what calibration/training period they used (the paper is behind a pay wall). Maybe Ned can help?
  25. Climate Change: Past, Present, and Future
    miekol #2: "Maybe its a coincidence that the temperature is rising everso slightly and the CO2 content of the atmosphere has risen everso slightly." All reconstructions of past temperatures (even the skeptic ones) indicate that the recent temperature rise is the largest in the past few thousand years. In what way is that "ever so slightly"? The phrase is even LESS applicable to CO2, which has risen 40%... and is now at a level not seen for at least 800,000 years. ptbrown31 #3: Once atmospheric CO2 levels are elevated the natural processes which can reduce them take thousands of years to work. Thus, on the time scale of the graph the difference between 'human industry emitting just enough CO2 to keep the atmospheric level constant' and 'human industry emitting no CO2' would be insignificant.
  26. New temperature reconstruction vindicates ...
    Albatross at 07:56 AM, I have and unless I overlooked it, there is no mention that the higher temperatures of the last two decades ARE NOT reflected in the Ljungqvist 2010 reconstruction itself. Perhaps others missed the omission as well? That then brings us back to the point of whether reconstructions are being validated by recent instrumental data, and if not, why not?
  27. The Phony War: Lies, Damn Lies and the IPCC
    @CW: you're still missing the point that overall temperatures were lower than today. No. See figure 1: http://www.geo.lsa.umich.edu/~shaopeng/2008GL034187.pdf
  28. New temperature reconstruction vindicates ...
    Johnd @63, please read the thread (i.e., Ned's comment).
  29. Positive feedback means runaway warming
    hadfield: The argument in the intro is: "These alleged 'positive feedback' cycles supposedly will build upon each other to cause runaway global warming, according to the alarmists." That is what is being controverted.
  30. Climate Change: Past, Present, and Future
    You might even add that... "Average temperatures at high latitudes may be 3 times and much, AND individual summer high temperatures much more than even that." In other words, don't just go running north if you're looking to cool down.
  31. Climate Change: Past, Present, and Future
    Miekol @2, "But its still a theory that CO2 is the cause" Did you mean to say "hypothesis"? Regardless, you are grossly over-simplifying things. A quick perusal of this site (which discusses and presents the relevant scientific literature on the subject) demonstrates that there is overwhelming evidence from independent sources which support the theory of AGW. It is no coincidence as some might wish to presume-- the evidence (from different scientific disciplines) is far too coherent for that. GHGs are not the only cause of climate variability of course, but recently radiative forcing from elevated GHGs has become a primary forcing mechanism and that is only going to increase as GHG levels continues to increase. If you want to debate what the equilibrium climate sensitivity is for doubling CO2, then that is still an open question. As of now, multiple, independent studies point to +3 C warming (globally) being most likely response to doubling of CO2.
  32. Climate Change: Past, Present, and Future
    "In other words, what would happen if humanity had suddenly stopped emitting CO2 in the year 2000." This should really read something like: "In other words, what would happen if humanity suddenly started emitting just enough CO2 to balance natural sinks and thus keep atmospheric concentrations at 2000 levels".
  33. New temperature reconstruction vindicates ...
    Rob Honeycutt at 07:04 AM, the tree rings was just a mere example to illustrate a point. I was asking specifically about which of those reconstructions that are the subject of this thread, thus the question was very much ON topic.
  34. Climate Change: Past, Present, and Future
    Its a wonderful graph. But its still a theory that CO2 is the cause. Maybe its a coincidence that the temperature is rising everso slightly and the CO2 content of the atmosphere has risen everso slightly. Its just like I cannot prove to you God exists, but you cannot prove to me God does exist. Both theories God and CO2 are currently unprovable. It just needs for someone to put two and two together and come up with four.
    Response: That CO2 is causing warming is confirmed by multiple, independent lines of evidence. We have both a shorter intermediate version of the evidence for an increased greenhouse effect and if you're hungry for more meat, a more detailed advanced version. On top of that, we have an extensive list of the human fingerprints on climate change that provide further corroboration. There is no shortage of directly observed, empirical evidence and it's all given to you on a silver platter here at Skeptical Science.
  35. New temperature reconstruction vindicates ...
    Based on the second graph that shows the warmest part of the Med-evil warm period being near .3c above "0" or avg to todays global .8c above normal. So we're half a agree oC above the med-evil warm period. Also I was reading that we're very close to the Holocene climatic optimum of 5,000-7,000 years ago->"The Holocene Climate Optimum warm event consisted of increases of up to 4 °C near the North Pole (in one study, winter warming of 3 to 9 °C and summer of 2 to 6 °C in northern central Siberia)[1]. Northwestern Europe experienced warming, while there was cooling in the south.[2] The average temperature change appears to have declined rapidly with latitude so that essentially no change in mean temperature is reported at low and mid latitudes. Tropical reefs tend to show temperature increases of less than 1 °C; the tropical ocean surface at the Great Barrier Reef ~5350 years ago was 1°C warmer and enriched in 18O by 0.5 per mil relative to modern seawater.[3] In terms of the global average, temperatures were probably colder than present day (depending on estimates of latitude dependence and seasonality in response patterns). While temperatures in the Northern Hemisphere were warmer than average during the summers, the tropics and areas of the Southern Hemisphere were colder than average which comprised an average global temperature still overall lower than present day temperatures.[4" http://upload.wikimedia.org/wikipedia/commons/c/ca/Holocene_Temperature_Variations.png If we're now warmer then the midevil warm period and possibly the climatic optimum then we have to go back to the at least 115 thousand years to find possibly warmer temperatures then today. 3-4c would put us back to where we where 15+ million years ago?
  36. New temperature reconstruction vindicates ...
    Michael @57, you must be telepathic. John Cook just posted this:
  37. Hockey stick is broken
    GC, as you're still ignoring the point and restating your incorrect assertions, I can only presume you can't actually answer my question: Why would you assume that every local temperature variation is recorded in full in a global dataset? And can you point to detailed examples of where the regional reconstruction fails to pick out regional climatic variations recorded in local history, and show how that has fed into and distorted the meta-analyses? I doubt you can. The climate science community's credibility has certainly not been affected in the slightest by the historical record.
  38. beam me up scotty at 07:12 AM on 30 September 2010
    Climate Change: Past, Present, and Future
    Of course this is too optimistic now, right?
  39. New temperature reconstruction vindicates ...
    johnd... I think I'm going to leave this one alone. It would be off topic for this thread and an issue that has long been put to rest as well. If you wish to rehash this one I would suggest this thread.
  40. New temperature reconstruction vindicates ...
    Rob Honeycutt at 06:49 AM, yes, those based on tree ring proxies being a prime example. Perhaps you can identify those reconstructions that are tracking recent instrumental records to date.
  41. New temperature reconstruction vindicates ...
    Rob @56, I think he may be trying to make a straw man argument about the divergence problem in some of the dendro chronologies from 1960 onwards.
  42. The Phony War: Lies, Damn Lies and the IPCC
    "Of course not. Your severe bias agaisnt AGW theory won't allow you to believe otherwise." "bias agaisnt AGW theory"? I haven't written anything about radiative forcing. All I'm doing is pointing out that the extent of a warming rate is low as declared by the IPCC and by daily, annual, and millenial scales of change, not particularly significant. I would gladly like to see any evidence you can provide otherwise.
  43. New temperature reconstruction vindicates ...
    Could someone direct me to an image that shows temps from 0-2100 i.e reconstruction plus IPCC estimates.
  44. New temperature reconstruction vindicates ...
    johnd... Are you suggesting the reconstructions don't track the instrumental record?
  45. Blog review of scientific coherence
    @Argus, post 25 You are missing the point here. Nowhere in the article the claim is made that a coherent theory is automatically a correct theory. Of course a coherent theory CAN be wrong. What the article states however is that an incoherent theory cannot be correct. This is not an article about the correctness of AGW, it is an article about how skeptic theories can be proved to be wrong, if they are internally incoherent.
  46. Positive feedback means runaway warming
    It illustrates a mathematical fact that is irrelevant to the action of the fast feedbacks, which are what the introduction suggests the article is about. So what's the point?
  47. New temperature reconstruction vindicates ...
    kdkd@54, Maybe this will help KL out (and these data only go till 2009). I have posted before, but some people seem to choose to ignore the facts: An updated figure (Fig. 21a), can be found here (pg. 48).
  48. New temperature reconstruction vindicates ...
    KL #43: Oh, and all the temp charts in this thread seem to stop at year 2000 - missing the last 10 years of flattening at a time when claimed AGW forcing is 'the highest decade in history'. In a sense I can't believe that you're still peddling this misinformation. Can you explain how the fact that the decade 2000-2010 is the warmest decade on record is consistent with your assertion please? In fact, I think I've asked you that question before; you've never provided a satisfactory answer (you may have repeatedly ignored the question), and yet still wheel out the same old poorly thought out repetitive rubbish without justification.
  49. Blog review of scientific coherence
    HR, your post @19 is OT, and so is this. Just for balance, here is their entire abstract. Pay close attention to the last sentence of their abstract: "While the IMP [internal multidecadal pattern] can contribute significantly to trends for periods of 30 years or less, it cannot account for the 0.8°C warming trend that has been observed in the twentieth century spatially averaged SST." So, internal variability can explain some of the changes in global SSTs on a short-time scale, but not the underlying long-term warming trend. Nothing new there, researchers are well aware of the role of internal climate modes in modulating global temperatures. And SS does not attribute all of the observed warming to higher GHGs as you state HR. Instead of arm waving please provide a link to where this is stated, or better still go and argue on a relevant thread. I can't wait to see how WUWT "presents" these results.
  50. Blog review of scientific coherence
    Philippe Chantreau It's nice for a skeptic to acknowldedge the existence of that acceleration, when so many are saying that it's cooling, = = = = = = = = = = = = = = = = There are many skeptics who acknowledge this, especialy among the luke warmers.

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