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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 84451 to 84500:

  1. Are you a genuine skeptic or a climate denier?
    My first impression was "Hey, John's getting serious here!", due to the wording being a bit stronger than the average article here on SkS, but then I realised you were writing for a different audience. I thought the point was well put, and forcefully so. This isn't a time to be tiptoeing through people's sensibilities, while the deniers are busily kicking doors in with their mining boots. The only way the general public will get to see the science, is if the science is put before them. Have added my comment to the moderators' queue, will be interesting to see how the 'discussion' evolves. I expect to see a post here in a few days listing the denier arguments put forward, and how often each one appears in the comment thread! :-P
    Response: [JC] Hmm, nice idea for a blog post. Noted!
  2. Philippe Chantreau at 17:49 PM on 30 May 2011
    CO2 limits will make little difference
    Mods, is Faramir the same person as Dorlomin?
  3. Of Averages and Anomalies - Part 1B. How the Surface Temperature records are built
    To Glenn Tamblyn In order to monitor if the global surface temperature is rising, an absolute value is not needed. A checksum will do, wherein even temperature anomalies become part of what can be considered "all things being the same".
  4. Are you a genuine skeptic or a climate denier?
    A well written piece, John. Excellent.
  5. Are you a genuine skeptic or a climate denier?
    Hi John, I regularly comment in The Drum. You'll probably find the comments come through in batches as the moderators find time to read them. I have to give you two thumbs up as I usually use Skepticalscience for the abridged version of rebuttals.
  6. Of Averages and Anomalies - Part 1B. How the Surface Temperature records are built
    Re #3 GaryB you wrote:- “The 1200-km limit is the distance at which the average correlation coefficient of temperature variations falls to 0.5 at middle and high latitudes and 0.33 at low latitudes." Thank you for making my point. Can any serious analysis expect correlation of temperature over 1200km? 1200m may just be satisfactory over land mass but is unlikely to be so for a land/water interface and absolutely not if a change of elevation is involved. It is all too easy to 'assume' correlations instead of establishing them; the latter is of course the scientific thing to do. Re #4 Chad you wrote:- " If one takes into account the land data interpolated into the ocean, the spatial coverages is well over 100% " 'Interpolation' means creating data points where you have none; interpolation always means making assumptions about how some function, arbitrary (free hand sketch) or mathematical (a very big subject!) behaves. There you have it; you must show how the interpolation is valid, something that has not been done. This validity failure corresponds exactly with the failure to establish the correlation I have mentioned above.
  7. Glenn Tamblyn at 15:33 PM on 30 May 2011
    Of Averages and Anomalies - Part 1A. A Primer on how to measure surface temperature change
    SoundOff I am not planning on looking at the specific issues of individual stations. Rather the purpose of these series is the general principles of how the temperature record is handled. That said, variations in stations, station ID's etc are unfortunately just what the teams who compile the records have to deal with. Unfortunately they don't control the information sources they are dependent on. The stations are controlled by various national meteorological services around the world. And the primary function of the stations is meteorological. The climatological function piggy-backs on top of that. So the national agencies do all sorts of things for all sorts of reasons, good & bad, and the temperature record guys just have to wear it and do the best they can with the data they get. Hence the importance of the Average of Anomalies approach.
  8. The Critical Decade - Part 1: The Science
    skywatcher , I don't think that a statistically decelerating trend would result in a decrease of all trends computed for any interval. This would be cherry picking. If you find a couple a value for which the trend is decreasing, and then another one for which it's increasing, what's your conclusion then ? DB, sorry, I'm not sure that I understood your explanation : does GIA produce a real decrease of SLR , and does the correction remove this decrease, giving (after correction) a higher result than what is really observed on the coasts ? I understand that the measurements should be corrected from instrumental effects, but GIA is not an instrumental effect : as I understand it is a real effect producing a real negative component, so why correct it ? for instance to my knowledge there is no "correction" from astronomical influences on the average temperatures ? it is just a part of the signal. and actually I didn't catch either your answer on how the model were validated if no statistical acceleration could be measured yet - how do you know that the models are correct ?
  9. Book reviews of Climate Change Denial
    What particularly warms me about this book is that in addition to its rigourous coverage of the science it goes further and suggests the broader social changes required to defeat the coming climate calamity. As demonstrated by these choice quotes, "A sustainable society will require fairness (equity) and justice locally and globally." – Climate Change Denial "Preventing the collapse of human civilizati­on requires nothing less than a wholesale transforma­tion of dominant consumer culture." – Climate Change Denial "We need to replace private consumption of goods with public consumption of services." – Climate Change Denial
  10. Climate Change Denial book now available!
    Does anyone else find it odd that Haydn and Cook got the science right in their book, when an alleged eminent climate scientist (Dr. Spencer) mangled the science in his recent book as outlined by Drs. Bickmore and Smith? Spencer, Christy and Lindzen have all clearly abandoned undertaking serious and unbiased science a long time ago, and have forsaken their credibility in the process. Sad then that there are those who are only too happy to aide and abet them in their misguided quest. And once again, please DNFTT (TB), you are only giving them an opportunity to further their nonsense. It is pointless trying to reason and argue with Dunning-Krugers and ideologues...pointless. Haydn and Cook have looked into the fascinating psychological underpinnings of the denialism and "skepticism" movement. The psychological aspect of those in denial or "skeptical" of AGW has been ignored for too long IMO. What is also interesting (and at times amusing) is that those afflicted with these traits, are so oblivious to their plight (some might say deluded) that they feel compelled to come here and defend their ideology, without realizing that with pretty each and every post they only succeed in illustrating the exact problems identified by Haydn and Crook. The best thing they can do is to actually be quiet, because they are only further undermining their credibility with each post.
  11. The Critical Decade - Part 1: The Science
    Folks, Watch the sleight of hand being perpetuated by the deniers of AGW and "skeptics" on this thread. Note their tendency to cherry pick regional transient events in the past and then confuse them with what has been happening globally and what will continue to happen globally as we continue to emit GHGs. This is nothing but tricks to obfuscate and an attempt to confuse people not familiar with the literature and the science. It is also the height of arrogance for someone to assume that they know more than the Australian climate commission and the US National Academy of sciences. Think of it as someone on the web telling you that the oncologists have gotten it all wrong on the links between tobacco and cancer. Who would you trust them or the oncologists? Well, the oncologists of course. Beware of the omniscient contrarians and confusionists.
  12. Can we trust climate models?
    Even climate skeptics use models but, for many, the model is simply that next year will be the same as last year. That sort of model is indeed unreliable.
  13. CO2 limits will make little difference
    So if there is no agreement at a conference, then there is no point in going it alone in say Australia?
  14. The Critical Decade - Part 1: The Science
    DB: That time frame had a temp structure simliar to todays temp structure. Actually, the examination of that time frame is quit good. The link you showed quibled that the construction in reference didn't continue to 2010. That is not what was important in the construction as one years values do not detract from the construction.
    Moderator Response: (DB) The mid-20th century warming experienced regionally in Greenland is a far cry from the global warming of the past 3-plus decades; the disinformation sites obfuscate that fact. Multiple lines of evidence point to a converging and consistent story: the world is as warm now as the HCO (the warm period of about 8000 years ago) and it is largely due to mankind.
  15. Of Averages and Anomalies - Part 1B. How the Surface Temperature records are built
    "Note that the large increase in contributing station numbers in the 1950s and subsequent drop off in the mid-1970s does not have much of an impact on percentage station coverage – once you have enough stations, more doesn’t improve things much."
    I have a post on my blog that illustrates this effect. From the late 1950s to the present, despite the varying number of stations reporting, GISTEMP accounts for virtually 100% of the Earth's land surface. If one takes into account the land data interpolated into the ocean, the spatial coverages is well over 100%
  16. Rebutting skeptic arguments in a single line
    Skeptics use a model too, but a completely unrealistic model because in their model human activity has no effect.
  17. Of Averages and Anomalies - Part 1B. How the Surface Temperature records are built
    damorbel, I take it the following escaped your reading.
    "“The 1200-km limit is the distance at which the average correlation coefficient of temperature variations falls to 0.5 at middle and high latitudes and 0.33 at low latitudes."
  18. Of Averages and Anomalies - Part 1A. A Primer on how to measure surface temperature change
    Damorbel, I find it interesting you can't see what is meant by correct, which should be obvious if you read the post.
  19. Climate Change Denial book now available!
    tallbloke @36, Judith Curry and Steve McIntyre's blog output are widely read by the denier community, and known by them to be widely read. Given that, it is ridiculous to defend them as being focussed on particular issues. And while they may occasionally mention their disagreement with more extreme deniers, McIntyre at least scrutinises the IPCC down to the level of detail of features of a graph that are not noticeable without magnification. Curry, in the meantime, swallows uncritically almost any slander of her colleagues while turning a blind eye to rebuttals. In fact, and contrary to Curry, McIntyre's criticisms have been taken apart and shown to be without basis by Deep Climate. So far as I know, there has been no retraction by either McIntyre or Curry. As other posters above have shown, this is not an isolated example. Their multiple slanders against Eric Steig last year provides another example. These examples coupled with their uncritical response to various denier howlers puts paid to any claim they have to be disinterested auditors of the science. Unless you can show me their retractions of their accusations against Briffa, Mann and Jones (and Steig) I can see no reason to revise my opinion.
  20. The Critical Decade - Part 1: The Science
    Thanks DB. I am always willing to learn if the source documentation is credible. One thing concerning the current loss of ice from Greenland proper I would like all to look at is the current rate of loss verses the rate of loss in the 1938-1950 time frame.
    Response:

    [DB] Why the focus on the 1938-1950 time frame?  Those who have looked at that period have not done a good job of examining it.

  21. Climate Change Denial book now available!
    NikfromNYC @42, it is rather hard to disagree with the claim that you can agree or disagree with statements from the book. After all, you can agree or disagree that two plus two equals four. The ability of people to agree or disagree has no bearing on the truth of the subject. What matters is are the statements true, and what is the evidence for that. a) “A sustainabl­e society will require fairness (equity) and justice locally and globally.” Here, the need for equity and justice follow straightforwardly from an ethical principle that is widely adhered to (or at least given lip service), that you should love your neighbour as yourself, or in its popular form, "Do unto others as you would have them do to you"; or as Kant puts it, "Act only according to that maxim whereby you can, at the same time, will that it should become a universal law.", or more popularly, "Act in such a way that you treat humanity, whether in your own person or in the person of any other, always at the same time as an end and never merely as a means to an end." More specifically, based on economic theory, if principles of justice to not apply, people can externalize the costs of their actions; and the richer and more powerful they are, the easier it is to do so. Given that people do externalize costs, they then receive the benefits without direct costs. From that, simple economic motivation encourages them to maximize their good, and ignore the costs which are not directly impacting on them. That, therefore, also forces costs towards a maximum. And that, is of course, not sustainable. b) “Preventin­g the collapse of human civilizati­on requires nothing less than a wholesale transforma­tion of dominant consumer culture.” Not sure I agree with this one. What is true, however, that to be sure of preventing the collapse of our civilization we need to reduce global CO2 emissions below 20% of current values by 2050, and it is very uncertain we can do so without radical changes to consumer culture. c) “Just because there a professor of something denying climate change does not mean it is not true, it is just that the professor is in denial. This is why one must make use of the prepondera­nce of evidence in science, the collective view.” As a general principle, the claim that "... it is just that the professor is in denial" is not true. But this statement is made within a book showing that, in fact, opposition to the IPCC consensus is almost exclusively based on denial. Therefore, in context it is an appropriate statement. tallbloke @49, the statement is not a statement about scientific method, it is advice for how to form opinions about science for those who do not wish to actually explore the science enough to truly understand it. Ideally the advise to such people would be: "Science only works by evidence and understanding, so if you do not wish to learn enough of the science to be able to understand the testing of it, you should have no opinion about it." Unfortunately, in the real world scientific knowledge impacts significantly on the appropriateness of policy choices in society. Therefore policy makers, which includes not only the members of parliament who must vote on the policy, but the electorate who decides who will be members of parliament, must form opinions about scientific matters. As it is unreasonable to expect all members of parliament, let alone all electors, to gain PhD level proficiency in every field which impacts on policy, the best we can advice them to do is to follow the advise of the consensus of those that have the relevant expertise, if such a consensus exists. In climate science, a relevant consensus does exist.
  22. CO2 only causes 35% of global warming
    I am struggling to understand what you dont understand. This reference to "control knob" is I think a quote from R Alley? If you can point me to where he uses it, I might be able to explain further what is meant. To my mind, CO2 is simply a forcing among others - something like solar and aerosols that can be varied independently of temperature (unlike water vapour). All the forcing are control knobs for climate.
  23. Climate Change Denial book now available!
    Any of them published?
  24. CO2 only causes 35% of global warming
    Moderator @ 2. The problem is organizing thoughts to fit the somewhat arbitrary threads. In 42. @ "How do we know CO2?" You replied that at the "top of the atmosphere" there isn't much H2O. I totally agree. I would like to know exactly what you meant by top of the atmosphere, but I wasn't quibbling. Here the same issue emerges in a different context, how CO2 controls water. A good place to evaluate that would be where they exist together in the trophosphere, no? I plead guilty to jumping around. I'm the monkey who eschews knee-jerk responses. Believe me, I read your links and think about your responses. I'm not here to waste my time or yours. Here it strikes me that you may be the one deflecting the issue by jumping to a different thread. Sure, CO2 raises temperature, temperature raises water vapor, water vapor raises temperature further; but temperature also raises CO2. I am holding your control knob, wondering exactly where to plug it in to this cycle, and exactly how it works.
    Moderator Response:

    [DB] There are literally thousands of threads here at SkS and none are closed (and I'm not sure if anyone has counted them all).  Some may be dormant or currently inactive, but fresh comments posted anywhere will not be ignored. 

    Since you were directed to specific, more appropriate threads where your questions would be better placed, why not follow those pointers & get the reolution to your questions you seek?

    As for the Control Knob, have you watched this yet?

    [Dikran Marsupial] If you wanted to know what I meant by top of the atmosphere, a good place to have started would be to read the real climate article I linked for your benefit. It explains how the greenhouse effect actually operates, and most of us here would benefit from reading it (I know I did).

    Temperature does cause CO2 to rise (all things being otherwise equal) because a warm ocean can hold less CO2. However, in the current situation, all things are not equal; specifically anthropogenic emissions have cause atmospheric CO2 levels to rise, and higher partial pressure of CO2 in the atmosphere causes increased absorbtion by the oceans (and by the biosphere - it is plant food). This dominates the increase in ocean emissions due to the warming of the oceans to date. The oceans are a net carbon sink, not a source.

  25. The Critical Decade - Part 1: The Science
    I think Hansen is still searching, which is what a good scientist does. He recognizes that the imbalance is not as he once thought and has started looking seriously at other factors. Like any other person, his search was somewhat in tunnel vision, but have now expanded. KL is showing what current observations show. I posted a paper on Greenland that seems to have disappeared. It showed that two glaciers were shrinking, and one was growing. The rate of ice loss in Greenland has yet to be resolved in a satisfactory manner. It is obvious from earlier periods of the Halocene when temperatures were warmer for 1,000's of years that it will continue to survive for 1,000's more years. This link will take you to course material that I would hope some can learn from. http://www.geology.iastate.edu/gccourse/sealevel/sealevel_lecture_new.html
    Response:

    [DB] You are welcome to pick one of the many Greenland threads (use the Search function to find the one most appropriate) & repost it there.  Quite frankly, your comment here about Greenland reveals an opportunity for you to learn much from those many Greenland threads.

  26. Climate Change Denial book now available!
    Alexandre@51, feel free to visit my blog, where there is free ranging discussion of several theories.
    Response:

    [DB] You do mean alternative hypothesis', don't you?

  27. Climate Change Denial book now available!
    tallbloke Forget jurisprudence. Stick to the evidence. Come up with a theory that fits the evidence even better than AGW, and then you have something worth a debate. Until then, it's just empty rethoric to justify inaction.
  28. The Critical Decade - Part 1: The Science
    Ken Lambert @ 48 would have us believe that SLR does not respond to decadal doubling in the rate of ice loss from the Greenland ice sheet, does not respond to growing loss of ice from WAIS and does not respond to water expansion as a result of ocean warming. Next he will be telling us that Polar ice loss is not occurring and that oceans are cooling. Hansen has a somewhat different view and one which is more credible than the those expressed by Ken Lambert. He appears to have only one mission in life, that of seeking to cast doubt on the views of those who are better informed than he is and who substantiate their views without cherrypicking – or am I being unduly harsh?
  29. Climate Change Denial book now available!
    tallbloke wrote : "JMurphy@41 Perhaps instead of taking 'Deepclimate's word for what Curry actually said when I cheekily presented her with the T-shirt you ought to check for yourself. Isn't that what sceptical scientists do? http://www.youtube.com/watch?v=dCjTRgHWTMs Now, for a start, she wasn't speaking 'for herself' but recapitulating Josh the cartoonists charicature of her." Well, I don't know how DeepClimate got into the discussion because I didn't link to him, and the link I provided for the video contains the youtube video you have given above. The exact same video that shows Curry receiving and looking at the T-shirt showing Climate Science in a dustbin, before proclaiming "My reaction to climate change". Who was she speaking for ? How do the words that can be heard on the video differ from what DeepClimate might have said she said ? And what could a "sceptical scientist" do, let alone have an opinion on this that is not based on speech that can be heard coming out of Curry's own mouth ?
  30. Climate Change Denial book now available!
    Tom@48, Hey Tom, it's Einstein who said it, not me. Popper never was my favourite philosopher of science. It's something of a moot point wrt AGW theory anyway, as no-one has yet devised a crucial experiment which can decide the issue. Instead we have the models, which generate 'scenarios'. So, do you go along with John on his jurisprudence type approach? Can you see any potential pitfalls in the rule of 'the collective view'?
    Moderator Response: [Dikran Marsupial] Firstly, the models generate "projections" based on "scenarios". Secondly those projections are falsifiable predictions (contingent on the scenario) and hence we are currently engaged in an experiment that can decide the issue. If we see cooling over the next century in which the models predict significant warming, then the model and the theory are falsified. Please no more discussion of falsificationism. The topic has been done to death already; those who have a good grasp of scientific method know as Einstein that there can be no proof; but they also know that not all unfalsified theories are of equal value (some are more corroborated than others).
  31. Climate Change Denial book now available!
    No, tallbloke, falsification is not the only criterion for evaluating theories. Your belief is called "naive falsificationism" for a reason.
  32. The Critical Decade - Part 1: The Science
    #58 - it's an exercisse in observation, and I think others can do better with statistical assessment etc. The point is that if warming was decelerating, we would expect to see that appending the last decade's data onto the warming trend since the 1970s would result in a decrease of the trend slope. What we actually see is that the first decade of this century was even warmer than we would expect it to be, based on 1970 or 1980 to 2000 data. Hence the trend from 1980-2010 is steeper than the 1980-2000 trend. Use whichever endpoint you prefer, but appending the last decade of data onto the data up to 2000 does not decrease that trend. Year-to-year variations are not important, and record years don't happen every year, hence why you need to use a climatically-significant period of time when discussing whether the trend has decreased or increased.
  33. If It's Not Sex, Drugs, and Rock 'n Roll, what is it? Creativity maybe?
    KR, your optimistic group is probably the best approach. The Marshall Plan for Europe might be the best example of directed investment for explicit development and political goals. The development we're now interested in is rather in redirecting certain activities rather than recreating whole economies after wartime destruction. We're now not so concerned with any such investment having an explicit anti-communist political objective. The political objective now should be to maintain civil society where it now prevails and to try to establish it where it has so far failed to flourish. Jobs and education are the prime success mechanisms here. Of course, no single country is now in a position to do this in the same way the USA did back then. Sex, drugs and rock'n'roll were my generation's fun contrasts to the chronic fear of nuclear annihilation and the dreadful reality of Vietnam. A little dose of hope and optimism with a large defiant upward pointing finger to the society that created those 2 horrors.
  34. Climate Change Denial book now available!
    “Just because there a professor of something denying climate change does not mean it is not true, it is just that the professor is in denial. This is why one must make use of the prepondera­nce of evidence in science, the collective view.” – John Cook (“Climate Change Denial”, 2011). This is an attempt to replace the principles of the scientific method with those of jurisprudence. "No amount of experimentation can ever prove me right; a single experiment can prove me wrong." -Albert Einstein-
  35. mike williams at 08:30 AM on 30 May 2011
    The Critical Decade - Part 1: The Science
    [ Snip ]
    Response:

    [dana1981] Please take the time to familiarize yourself with the site Comments Policy.  In particular "No off topic comments".  This topic has nothing to do with cap and trade or Flannery's correct comment that while we can slow global warming, we're not going to cause cooling.  If you would like to discuss Flannery's comments, take it to CO2 limits won't cool the planet

  36. Solar Cycle Length proves its the sun
    Re John Cook, 6/26/10, Solar Cycle Length A five parameter, causal filer of the Wang, et al. (2005) solar radiation model predicts the entire 140-year HadCRUT3 record of annual surface temperature with one standard deviation of 0.11ºC. With three parameters, the fit is 0.13ºC. See SGW. The accuracy is within 10% (variance reduction ratio of 79.0% vs. 89.3%) of IPCC's non-causal, smoothed estimate for surface temperature. Published 3/27/10, rev. 4/17/10. Is there a comparable result in all of climatology?
  37. Climate Change Denial book now available!
    44 - "You need to be a little more sceptical of people who have a personal axe to grind, and check 'facts' for yourself." Yes, indeedy.
  38. The Critical Decade - Part 1: The Science
    skywatcher, I'm not sure of what you're really doing - just comparing two trends with some arbitrary end points ? with a noisy signal, I guess you can easily adjust the end point to get an increase of the trend. But that's not what is usually considered as a significant acceleration - you have to compare the difference with the statistical uncertainty, at least. DB : thanks for the plots, but my question wasn't about the projections, but their validation. I mean, it's easy to plot the result of models, but when do you expect that the acceleration will be clearly measurable ? concerning SLR, what does this GIA stuff really mean ? is the "real", observed, SLR described by the curve with, or without, the correction ? but anyway, since the correction seems to be taken as a constant, it shouldn't influence the acceleration. So what's the current acceleration rate, say for the smoothed 30 last years ?
    Response:

    [DB] SLR plots from UCAR/NCAR need to have the corrections applied to them to account for regional isostatic rebound effects and seasonal effects to be properly filtered out.  If using the unadjusted/improperly adjusted data, one risks writing posts on CO2 snow...

    SLR

    And from Church and White, 2011:

    C&W SLR 1860-2010

    The Tamino posts I linked to were essentially validating the existent temperature records, not models or projections.  Since the future hasn't happened yet (some existentialists are sure to quibble on this point), I supplied you with 2 links discussing 2 recent temperature scenarios, one by MIT and the other by the Royal Society (IIRC).

    If you're asking for clues to recognize when shifts are occuring, then I would suggest monitoring the Mauna Loa CO2 monthly updates (you can also get CH4 updates there as well), the GISS temperature trends (updated monthly), droughts in the Amazon and the volume of Arctic Sea Ice lost each year relative to the mean and the trend.  Also watch for papers on evapotranspiration changes, desertification, arable land crop productivity, etc.

    CO2 and CH4 will give you some idea of temperature trends to come (30-40 year lags built-in to the system...we are currently experiencing the effects of the CO2 emissions of the 1970s now).  The others will give you an idea of how much the rate of change is itself changing.

    If the natural oceanic and land sinks decline in their ability to temporarily sequester anthropogenic GHG emissions (and there is some evidence that they already are), then that will be revealed in the Mauna Loa data.  But keep this in mind:  the past, while a guide, is no good indicator of future results WRT to climate and climate change.  Temperature change and climate change are multifactorial; the change to come, as evidenced in the MIT and RS papers, is expected to be non-linear.

    What to expect when?  This is about as good a guess as any:

    21st Century warming to come

  39. The Critical Decade - Part 1: The Science
    Camburn #56: You like cherries? especially extra(polated) juicy ones? Have you read Polyak et al 2010 and the attendant sources therein? You would see how picking a carefully-selected single site does not tell you about all the Arctic, and also a wealth of evidence pointing to Arctic sea ice being less extensive now than in several millennia. The graph from Kinnard et al 2008 would show you how ice extent would have to be ~1.5 million sq km (~18%) lower than in any other estimated extent from 1870-1960 in order to be comparable to the past few years. Much like individual logs of submarines surfacing in polynyas at the North Pole say nothing of overall extent, neither does a single log of a single journey in a single part of the Arctic.
    Response:

    [DB] To say nothing of logs detailing 12-15 meter thick ice...

  40. Climate Change Denial book now available!
    This would be this Judith Curry or this Judith Curry? Sounds like she's plunked herself into a camp that doesn't require relying on hard evidence and science any more... Reading the RealClimate exchange where Judith Curry claims to support Montford's book with blog-like misinformation and outright falsehoods, then wonders why Gavin hammers her for her unfounded opinions, then claims she wasn't really having an opinion on the book, is both eye-opening and sad. She displays none of the expected critical academic traits in her treatment of climate science therein, and appears to fail to comprehend why the misinformation she presents is offensive to many. Sadly, she does indeed appear, through her very own words, to be a biased scientist.
  41. Of Averages and Anomalies - Part 1B. How the Surface Temperature records are built
    I would like to echo post #1 To validate your procedure I suggest that you find what the actual correlation (in space and time) exists between the stations. At present the values for this parameter appear to be quite arbitrary.
  42. Clouds provide negative feedback
    RW1 - You might be interested in Wylie 2005. They looked at various satellite measures of cloud cover over the last 20 years. The High Resolution Infrared Radiometer Sounder (HIRS) found no significant cloud trend, while the International Satellite Cloud Climatology Project (ISCCP), with slightly different instruments, found a slight decrease in cloudiness over that period. Keep in mind that while specific humidity (total amount of H2O) in the atmosphere may be rising with temperature, relative humidity (relative to the total amount air can hold at any temperature) may remain steady or even decrease. So - steady or decreasing clouds with rising temperatures, neutral or positive feedback to warming.
    Response:

    [DB] Fixed Link.

  43. Of Averages and Anomalies - Part 1A. A Primer on how to measure surface temperature change
    Re OP you wrote:- "Obviously both values don’t match what the correct value would be if station C were included, but the second method is much closer to the correct value." I am so glad you are able to say which is the 'correct' value for temperature; it seems fully in accordance with the principles of scientific climatology!
    Response:

    [DB] Glenn was using a specific simple example to illustrate the principles underlying the measurements of the temperature records.  If you were thanking him for the clarity of the illustration and the sense it made, then you're welcome.

    If, on the other hand, your had other, ideological, meanings for making your comment, then those ideological meanings and intimations have no place in the science-based dialogues here.

  44. Climate Change Denial book now available!
    JMurphy@41 Perhaps instead of taking 'Deepclimate's word for what Curry actually said when I cheekily presented her with the T-shirt you ought to check for yourself. Isn't that what sceptical scientists do? http://www.youtube.com/watch?v=dCjTRgHWTMs Now, for a start, she wasn't speaking 'for herself' but recapitulating Josh the cartoonists charicature of her. Being the good sport she is, she took the gift in good humour, and brightened everyone's evening by making a laugh out of it. People from both sides of the debate are sat either side of her. It brought us together in laughter, and helped us overcome our differences. The working groups next day were noticeably more able to consult and generate statements on common ground together. This was a positive result. To twist the true situation (and remember, I was there, 'Deepclimate' wasn't) into some kind of accusation that Judith Curry is a biased scientist, is about as far from the truth as you could stray. You need to be a little more sceptical of people who have a personal axe to grind, and check 'facts' for yourself.
  45. The Critical Decade - Part 1: The Science
    Being the museum, owners of the log of the St Roch, won't allow it to be digitalized and more readily available, I can only suggest that people purchase the book. It is available on the Vancouver museum site. Capt Larson did not say there was no ice, but I can say that he was very surprised at areas that there was litteraly no ice, where he thought passage would be extremly difficult.
  46. The Critical Decade - Part 1: The Science
    In reference to the map: 1. The southerly route is used on an annual basis by the Canadian Coast Guard to replish supplies to the cities/outposts on the northern side of Canada. 2. The northerly deep sea route is much more desireable as a commercial route as the water is consistently deep. The area between Banks and Victoria Islands is somewhat treacherous. If the area to the north of Banks open to the Beaufort Sea, that would/could become the route of choice. The black carbon emissions from China/India etc are hastening the ice melt. When and IF the people wake up and demand cleaner skies and healthier lives, that source should become more of a marginal effect. The rate of growth in China of coal fired power plants with wide open smokestacks continues to boggle my mind, so within the next 10 years I don't see any decrease that will slow the melt of the Arctic. The black soot provides approx 4w/sq meter of loss of albedo. This is a huge amount. I don't know how to pressure China/India etc to clean up their acts. Only the people living there can do that. As far as other countries with a lot of charcol burning etc......that is extremely difficult as that is their main source of cooking and heating. This is an area that has only recently been studied, yet has been known about for a long time. The effects are devasting to say the least and the teck is here, proven, and veryyyyyyy benficial to overcome this. Not demanding and doing so is totally foolhardy.
  47. John Donovan at 06:09 AM on 30 May 2011
    Skeptical Science Educates My Students
    I previously wrote to "apirate": But the phrase that struck me most of all in your response was the statement "The various science departments at that school are heavily slanted towards support of the AGW theory." I find that wording itself "heavily slanted". How can the faculty be "heavily slanted" if they agree with the current expert scientific consensus? Would we not expect that a science faculty agrees with current scientific expertise? Would you also describe the science faculty there as "heavily slanted" towards evolutionary theory? I find your wording most problematic. Please share the survey data with us as I would be most interested to understand why one college in your area (even considering it is in the southern US!) is noticeably outside the scientific mainstream on any field of science. I can't provide an opinion without more data. I have to add that I am disappointed that "apirate" has so far not only not shared his polling data, but neither has he named the two schools in question, which makes his claims undocumented at best and also without the possibility of being confirmed. But perhaps even more interestingly nor has he explained his "heavily slanted" wording quoted above.
  48. Climate Change Denial book now available!
    Nik: "I would like to point out to potential readers that your book contains certain political statements that they can either agree or disagree with" Thank you, Nik. I never would have realized it. Shocking suggestions, I must say. I certainly won't let children or some of my more idiotic friends read it. They'd immediately be turned into commies! Gasp! Sarcasm off. Since even the tiniest bit of cultural production has political content, your warning is akin to saying, "Be careful! The ocean is wet!" Garrrr . . .
    Moderator Response: [Dikran Marsupial] italic tags fixed
  49. Clouds provide negative feedback
    Sphaerica (RE: 159), "3. Your argument that models "assume" and require a positive cloud feedback is wrong." It's not really "my argument". The IPCC report specifically says this in the fine print, which I have posted here. "While clouds do represent a large area of uncertainty in the models, it is incorrect to think that the scientists who have done the modeling have not thought things through a little more carefully, and in more detail, than you have. You cast aspersions by generalizing their work into the word "assume," and yet provide no direct evidence (other than the general positive/negative thing) that their work is not well considered." No, I have not seen the evidence their work on the cloud feedback has been carefully considered at all, especially because it seems to ignore the basic physics of water vapor and clouds.
  50. Clouds provide negative feedback
    Sphaerica (RE: 159), "2. Your theory is inconsistent with the observational evidence (Dessler 2010) that demonstrates a positive, not negative, feedback in response to short-term warming. While this cannot necessarily directly support a long-term positive effect, it directly refutes your "was negative before, so must be negative in the future" theory." Dessler 2010 is primarily just looking at TOA net fluxes and temperatures – he’s made little (if any) attempt to carefully discern cause and effect, and has not come up with any physical reasons or mechanisms behind his interpretation of the data. He admits in the paper at the beginning that the net effect of clouds in the current climate is to cool by about 20 W/m^2, yet doesn’t seem to ascribe much significance to this or express any curiosity as to why this is the case when clearly it needs to be explained. Furthermore, I notice that the SW component is also positive, which seems to be consistent with decreasing clouds causing the warming rather than warming causing decreasing clouds. Even if the claim is warming causes decreasing clouds for positive feedback, how is this consistent with increasing water vapor from warming? Does increasing water vapor from warming cause decreasing clouds? That doesn’t make any sense since water vapor concentration drives cloud formation. It seems to me that unless Dessler can explain all of this and corroborate it with all the other data and system behavior, he really doesn’t have a case.

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