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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 107001 to 107050:

  1. The human fingerprint in coral
    Some interesting work suggests coral reefs may also be under threat under threat from non-anthropogenic sources of CO2 and other anthropogenic non-CO2 related hazards . The impact of non-anthropogenic CO2 is presented here as a model of the potential impact of anthropogenic ocean acidification. Some reefs, however, seem to have evolved resilience in the face of rises in temperature . It seems some corals have evolved resilience in the face of temperature rises . I note concerns about acidification is presented here as related predominantly to dissolution of calcium carbonate. However, problems with acidification are complex in that acidification impacts more strongly on bleaching and productivity than calcium carbonate formation. I could not find much other material relating to coral resilience to acidity beyond this article in a sceptical source - I did not have the time or inclination to follow up the references in the article but thought I'd include the link for what it's worth. Looking at a peer-reviewed source, it seems that coral symbiota involved in initiation of coral bleaching events show greater capacity to pass on traits associated with resistance to warming than do corals - not a good outlook, if this is correct. At the same time, the appearance of corals in the Ordovician when CO2 levels were much higher (though temperatures lower) may warrant further discussion.
  2. SkS Housekeeping: right margin
    I've always used the highest resolution the computer can handle, so the change makes the SkS layout now look less like it was designed to fit under a postage stamp. Glad to hear that the 'no more than 800 pixels' web page standard is finally dying. For the right column... I'd suggest that might be a good place for some of the 'hidden' / 'lost' pages. The one that I always have trouble finding is the page where you can put in sort conditions like 'peer reviewed', 'skeptical of AGW', and 'within the last month' to get a list of submitted links. I've found that a good way to keep up on the latest research... when I can find it. Also, the comments policy is linked by the comment box, but nowhere on the main page. I know there have been other pages I've seen once or twice and then lost track of.
  3. SkS Housekeeping: right margin
    Design wise it is much better. The mobile phone apps weren't the sort of thing that had a higher level of importance than arguments and other info. So shifting them to the left gives a better balance.
  4. The human fingerprint in coral
    And I forgot to mention the standard sample, because I didn't konw the coral standard. For ice cores they use standard mean oceanic sea water. Mike's answer should help clear up the coral bit :)
  5. The human fingerprint in coral
    Eric L: the change is per mille. Which is like per-cent, but per thousand rather than per hundred. So it's a fractional change, but to get to per-cent divide the figures by 10. (this sounds small, but it can be a very sensitive test - it's the sort of stuff they use to determine temperatures from ice and sediment cores)
  6. The human fingerprint in coral
    Eric L- The y-axis scale is given in "delta" units which represent the deviation in parts per thousand of the 13C/12C ratio in a sample - coral calcium carbonate in this case - measured relative to that in the international reporting standard for carbon stable isotopes - PDB, a carbonate fossil (belemnite) in the Pee Dee Formation in South Carolina. A value of -3 indicates that the 13C/12C ratio of the sample is lower than that of PDB by 3 parts per thousand or 0.3%.
  7. The first global warming skeptic
    Riccardo I have read a similar description over at RealClimate and the general point being made seems to be that a major part of the increased absorption involves CO2 (and I presume other GH gases in their behaviour) absorbing at some central wavelengths first and this absorption then 'spreading' to adjacent absorption lines at higher concentration. You describe it as following a gaussian distribution. The point that isn't clear is why, if CO2 has a range of absorption frequencies, the central lines would absorb preferentially and thus saturate first. Why don't we see equal degrees of absorption across all the absorption lines. All the descriptions I have read to date make good sense apart from the explaining the causal mechanism of WHY that gaussian spread occurs. Is this theoretically derived, observational, what? This seems the only missing piece in the puzzle as far as an explanation of this goes.
  8. The human fingerprint in coral
    I find the y-axis of the graph a little confusing -- it appears to be a negative percentage change, but it isn't clear what the baseline the change is being measured against is. Also, one thing you could make clearer is that I don't think the total amount of C13 in the atmosphere is declining, it is the percentage of all CO2 which is C13 that is declining.
  9. SkS Housekeeping: right margin
    PS. with "predetermined maximum width" I mean: predetermined maxiumum FIXED width, so that the center column is already the right size before the right column gets built.
    Response: The centre column already did have a fixed width (I increased it from 520 to 600 pixels in the new design so the centre didn't look swamped by the surrounding margins). However, I've added a few extra constraints in the code so hopefully the columns will display at the right width even while the page is still loading.
  10. SkS Housekeeping: right margin
    @ Moderator: How did you know I was using Firefox? ;P Anymoo, it worked :D but would it be possible to either give the center column a predetermined maximum width or create the right column before the center column? It now goes like: Left column, ENORMOUS center column (yes, I have widescreen) all the way up to the right, lots of movement, right column stealing width to squeeze in, still more lots of movement, ahhh... finished! Even though I *do* love SkS, the page buildup has always been a bit on the slow side (in fact SkS made me change from IE to FF, because in IE the country flags on top of the pages.... appeared.... kind.... of.... one.... by.... one.... which was a bit annoying), and imho it would look a lot better if the center column gets built without all the movements (i.e. after the right column). Don't know if it's HTMLwise possible, though. ;)
    Moderator Response: Firefox is to IE what color TV was to black and white: a vast improvement in experience and enjoyment of the medium. Once the initial transition/learning curve is over, you wish you'd done it years earlier.
  11. Carbon Dioxide - Everyone's Favorite Pollutant
    BP #140 I agree the mining disaster in Hungary is terrible (and I have Hungarian connections in my family). However pollution can manifest itself in different ways, in much the same way that the disease process can be acute or chronic.
  12. Skeptical Science now an Android app
    Thanks for the app! To follow up on the QR code: it's a way to quickly get to an app download by taking a picture of a barcode with the phone in your android device. There's a link to this app at Skeptical Science Android App. John, you might be a able to put the barcode image right on this page.
    Response: Have added it above, thanks for the suggestion.
  13. gallopingcamel at 16:09 PM on 11 October 2010
    Carbon Dioxide - Everyone's Favorite Pollutant
    Berenyi Peter (#140), Your countrymen are experiencing real pollution and you have the sympathy of people all around the world. It is hard to understand the extent of such problems but I suspect it will be more severe than Chernobyl but less horrible than Bhopal. Our problems with the Gulf oil spill are probably tiny by comparison. Of course I will send some money to that link you provided; I wish I could afford more.
  14. Temp record is unreliable
    Re: The Inconvenient Skeptic As scaddenp rightly points out, you are in error. The atmosphere is layered, like an onion. The different dataset sources measure different things. Attempting to homogenize them into a "blended" dataset is less like comparing apples to oranges than it is comparing apples and breadfruit. Attempting to shift the focus of the debate to "skeptics using satellite only and the AGW crowd using CRU only" is also misleading. Scientist use the theory that best explains the preponderance of the data. Multiple, independent lines of evidence (of which station data and satellite data are but two) show that our world is warming and that we are causing it. That is what science is telling us. Most "skeptics" choose to focus on part of the evidence available rather than all of it. I can appreciate wanting to roll all of the instrumental data (station and satellite) into one neat package, but it isn't necessary. It's rather like combining the four Gospels into one continuous narrative: while interesting, it doesn't tell us anything we don't already know. The Yooper
  15. Temp record is unreliable
    Well me, if I wanted to know what is going on in the surface record, I would use the surface temperature record. If I wanted to know what is going on in lower troposphere, I would use MSU data. Giving the complexities in the relationship, I would certainly not be interested in a combination, least of all one put together with arbitrary weightings. What would you think of someone doing this in your area? Think you could get such an approach published. I did indicate how you would combine them properly but first you solve a very difficult problem. Also, the idea that "skeptics" use satellite and AGW use surface is bogus. It is use for what purpose.
  16. Carbon Dioxide - Everyone's Favorite Pollutant
    Weeds are perfectly ordinary plants in the 'wrong' place. Noxious weeds are those in the wrong place whose vigour threatens an environment or a crop. There are good reasons for authorities to ban or control them. (There's a similar argument about vermin and other pest animal species.) Pollutants are substances in the wrong place and /or the wrong quantity. (Flooding other than normal predictable water flows for the area is in the same category.) Authorities have good reason to insist on proper drainage arrangements for their own and for private property. They also have good reason to regulate all sorts of things from tanneries to chemical factories to private incinerators - write your own list. Very few of the things that need regulating, controlling or eradicating are "unnatural" or inherently poisonous. They're the simple consequence of human activity. Careless or thoughtless activities like those that introduce vermin or weeds or overflows to an area. Others involve lack of foresight or knowledge when undertaking actions like introducing cane toads to Australia or choosing to expand coal fired power technology around the world when other options were available. Regulation, control or eradication are all appropriate responses when the dangers are known.
  17. The Inconvenient Skeptic at 15:29 PM on 11 October 2010
    Temp record is unreliable
    Doh!!... Those darn links... Working link. I did indicate that the satellite measurement is a measurement of wavelength. I am not saying that it is perfect method, but none of them are perfect. Hadley and CRU also give different results. This is the one place where anomaly is beneficial. I think it is a more useful method than all skeptics using satellite only and the AGW crowd using CRU only. Instead of arguing about interpolation methods and UHI I am using more sources of anomaly data. If you have a better proposal for incorporating satellite data into a standard record I am all ears. I don't particularly care what method is used, but a single set that attempts to use the station and satellite data would be helpful for all.
  18. SkS Housekeeping: right margin
    Me too, looks good.
  19. Temp record is unreliable
    John Kehr - you do realise that they dont measure the same thing? (and your link doesnt work). Satellite data lower troposphere is temps through section of atmosphere at around 4000m. Try reading up on how MSU measurements are made, corrected etc. ALL of them valuable, all of them show a warming trend. I think your method of combination is bogus - you need to find a way to reflect the way lower troposphere temperature operates with surface temperature.
  20. The Inconvenient Skeptic at 14:47 PM on 11 October 2010
    Temp record is unreliable
    Using only station records when there are two versions of satellite data available is a form of cherry picking. Since those are limited time wise, I propose that a compromise set be used. This is the set I will use from now on for the instrumental period. It is a merged set that uses the CRU, Hadley, UAH and RSS. Details are available on my site as well as the file. No set is perfect, but I hope that using a set like this is acceptable, more reliable and reduces the complaints from each side of the debate on which set of data they use. http://theinconvenientskeptic.com/2010/10/what-global-te…rement-is-best/ John Kehr The Inconvenient Skeptic
  21. SkS Housekeeping: right margin
    I like it.
  22. SkS Housekeeping: right margin
    Slight aestethic problem here ... in the Arguments, the light red boxes, light green boxes, images and text all used to have ± the same basic width and now they're all different, which looks a bit like the pages aren't fully done yet. :') Or are we still looking at a Work in Progress?
    Moderator Response: If you're using Firefox (like me), hold down the left SHIFT key and hit your browser refresh button to fix. Mine was looking funky until I performed that action.
  23. SkS Housekeeping: right margin
    James Wight at 13:35 PM Mine was too... now its fixed :-)
  24. SkS Housekeeping: right margin
    The new design isn't displaying at all well in my browser. I don't know how to paste screenshots here, but the header image is not long enough and repeats on the right side of the screen. All the text is centred which looks really garish. The thermometer is not displaying properly either - the bottom is sort of separated from the top.
    Response: That would be because your browser is loading the cached version of the style sheets. I've renamed the style sheet filenames to sidestep the whole caching issue - should be fixed for you now.
  25. The first global warming skeptic
    Phil at 22:23 PM says "Firstly the Sun emits little or no IR radiation; photosynthesis absorbs a lot of visible light (not green, obviously!). Subsequent processes such as respiration convert that energy to vibrational (IR) radiation which the atmosphere can absorb." Taken in the context it was written that makes sense... but it does also come across as a little misleading, as in it implies that IR is the result of biological process's. I know thats not what youre meaning. Radiation is a product of the temperature of its source. Shortwave from the sun is coming from 5800k, red light is the longest visible wave length to our eyes(think red hot iron etc) , infra red is longer than red light, and thus has come from a source cooler than this, a longer wave length than is visible to our eyes. But its a product of the temperature of the source material(emissivity pending) , on earth, the absorption of shortwave, by materials opaque to its wavelength... earth/ water/ rock etc. I know you were talking specifically about biological endothermic/exothermic process's... but i can see that being misinterpreted.
  26. Carbon Dioxide - Everyone's Favorite Pollutant
    Even water can be a pollutant, although that is not usually the term used for water. My next door neighbor has a dam that causes flooding on my property-it is pollution to me. The government has rules controlling how this water can be discharged, unfortunately for me I have to clean up their mess. Where I live in Florida there are constantly problems between neighbors caused by water diverted from one property to flood another- pollution is a suitable term for these problems. Because water is easy to clean up we don't worry about long term consequences like we do for CO2. The disaster in Hungary is terrible, but the floods in Pakistan, likely caused at least partly if not completely by AGW have killed many more people. The defination of pollution has not been blurred by this action. Pollutants were defined by the act decades ago and now business and deniers want to change the defination of pollutants so that CO2 is not included. The court ruled that that is illegal. Tetraethyl lead was not immediately toxic, it was the long term accumulation and exposure that was bad. Freon also caused no measured problems at the time it was banned.
  27. It's freaking cold!
    Re: Tom Loeber Take this to heart: the only reason you have comments deleted is because you don't adhere to the comments policy. Period. Don't ascribe to malice on others what is more appropriately due to non-compliance on your part. You control your posts being moderated. No one else. If you don't want to abide by the same rules that everyone else does, then perhaps (in the final evaluation) you are banning yourself. The Yooper
  28. It's freaking cold!
    Yeah. I think banning me from that other thread led to a cross post here by another other than me wanting to continue our discussion. Me thinks the moderators screwed up and essentially messed up two of their own offerings. Try to take it easy there mods. The heavy handedness is not what makes the best theories.
    Moderator Response: There is no mechanism for banning any user from a particular thread. What you're seeing is more than likely a bug relating to the site (either HTML or PHP related).
  29. Climate Cherry Pickers: Falling sea levels in 2010
    BP #105 Accelerated sea level rise seems unlikely from the graph that you present there, but that's only a part of the story. I was just explaining one way of doing the job properly from empirical data. Note this thread is about "falling sea levels" and there don't seem to be claims about accelerating sea level rise. I suspect that we aren't really able to think about global warming caused accelerating sea level rise on an empirical basis yet, although it's quite possible that there's theoretical support for the idea. Again BP, you should use the above to guide the way that you make conclusions from a scientific approach to this topic. You'll note that it's a much more measured, conservative and balanced approach than what we usually see from you.
  30. It's Pacific Decadal Oscillation
    Roy Spencer classifies the PDO index as a radiative forcing, because he claims that changes in the phase of the PDO are significant enough to cause a change in global cloud cover which alters the absorption of sunlight and escape of heat. Does this hold up to scrutiny?
  31. Global warming is accelerating the global water cycle
    Climate scientists are able to work wonders with numbers. In spite of the wild variations without understandable reason, Syed & Famiglietti were able to extract highly significant trends (actually 3 trends for each parameter..... One for an early period. A second trend in the opposite direction for the a later period. And a third trend for the entire period. 7 of the trends were p<0.001, 2 of the global precip trends were only signficant to p<0.01) for each of the parameters. This is amazing for those parameters which are small differences of large quantities with significant variation and errors. For example, the discharge (R) is the (delta in ocean mass) + (global ocean evaporation) - (global ocean precip). It is also striking that Syed and Famiglietti were able to detect trends much smaller than the variances between the multiple observational datasets of the same parameter, such as the global ocean evaporation (HOADS, SSM/I, and OAFlux). (See table S1). As I noted above, the discharge (R) has both an upward trend in the first 4-1/2 years, then a downward trend in the last 7 years, and an overall trend over the entire period that is upward. The summary below only lists the overall 1994-2006 trends, although Syed and Famiglietti show 3 significant trends for each parameter in Figure 2. Discharge (R) Mean 36;055 km3∕y Std dev 16;164 km3∕y trend 540 km3∕y2 Evaporation (E) (SSM/I, OAFlux, & HOAPS) Mean 409,152km3∕y std dev 10;236 km3∕y trend 768 km3∕y2 Precipitation (P) (GPCP & CMAP) mean 374;220 km3∕y std dev. 14;221 km3∕y trend 240 km3∕y2 Global-ocean mass change (ΔM∕Δt) (GMSL minus steric sea surface height) mean 1;044 km3∕y std deviation 14;328 km3∕y trend 23 km3∕y2
  32. It's freaking cold!
    #22: "not just years or tens of years or even thousands of years, we should also consider hundreds of thousands of years" Nice. You went from worrying about daily lows at LAX to glacial cycles, which have nothing to do with the current situation. Isn't that called obfuscation, a tried and true denier tactic? "at times experts have been quite mistaken in a major way" Sure. But do you drive over bridges? They fall. Fly in airplanes? They crash. The work of experts is all around us; we can't live buried in the suspicion that they are all in cahoots and out to get us. I spend far too much time reading papers and looking at publicly available data; I am glad to read an expert analysis to help me digest it all. The point is, I am willing to incorporate into my evaluation the analysis of someone who knows more than I do. "Always realize we can only hold onto an opinion." Well, as the saying goes, you're entitled to your opinion. But you aren't entitled to your own facts.
    Moderator Response: It's time to take this discussion to a more relevant thread. Anybody who wants to continue, please use the Search field to find posts about "consensus" and pick the one of those you think is most relevant.
  33. Climate Cherry Pickers: Falling sea levels in 2010
    "No amount of statistics would turn a curve like this into an accelerating one, you know it as well as I do." Aah, but BP, some cherry picking and inappropriate data manipulation can change it into a slowing trend or even a decreasing trend ;) Again, I must politely ask you to please reply to my questions posed earlier at #89. They are relevant to this thread. Thanks.
  34. Berényi Péter at 09:31 AM on 11 October 2010
    Climate Cherry Pickers: Falling sea levels in 2010
    #101 kdkd at 08:29 AM on 11 October, 2010 Well strictly speaking you're making that conclusion due to a limitation in the methodology of regression (see this post which demonstrates the staggering lack of power in these univariate not-corrected for the limitations of time series procedures). Come on, get real. No amount of statistics would turn a curve like this into an accelerating one, you know it as well as I do.
  35. Climate Cherry Pickers: Falling sea levels in 2010
    BP: The above (posts #101-103) is indicative of how one goes about producing measured conclusions to a set of information. This is as compared to the approach that you take of taking a single piece of information and then over-extending your conclusion to fit your preconception (which is indicitative of confirmation bias rather than of the mechanism under investigation).
  36. It's freaking cold!
    JMurphy @25 asks of Tom Loeber How do you trust even your own conclusions ? I was wondering why Tom trusts the advice of David H. Freeman. How do we know that Mr. Freeman is not one of "the experts that keep failing us ?" Then my head started to hurt...
  37. Climate Cherry Pickers: Falling sea levels in 2010
    Finally, the nature of the variable(s) that caused this heteroskedascity would be strongly suggestive, but not proof of some kind of causal relationship.
  38. It's freaking cold!
    Tom Loeber at 07:22 AM, what I think it actually comes down to is a persons ability or otherwise to think laterally. Many of the examples in your links are of people demonstrating inability to think laterally. Whilst most people like to think that they are lateral thinkers, unfortunately the education process most people pass through tends to reinforce the logical thinking processes, some institutions I have observed even actually discourage lateral thinking. At lot depends on the staff at the institution, there are only so many "inspirational" educators around, many are the tried and proven "sloggers" that follow the logical processes that teaching by the book demands. The climate change debate is an excellent example where the reliance on peer reviewed papers and the necessity for all processes to be reduced to an equation to explain the physics involved leaves little room for lateral thinkers, especially amongst those who are students of the subject.
  39. Berényi Péter at 08:44 AM on 11 October 2010
    Carbon Dioxide - Everyone's Favorite Pollutant
    If anyone is interested in how real pollution looks like, watch this: In an industrial disaster 700,000 m3 of highly alkaline (pH 13, powerful lye) heavy metal laden red mud (waste product of aluminum manufacturing) flooded several towns, rivers and the countryside, seven killed, hundreds injured with next to lethal burns. Takes a year to clean up, for plant life if ever, several decades to recover, townships destroyed can never be rebuilt at the same place. Liability insurance of the company responsible for it covers $50,000 in damages, its capital is also negligible compared to losses and expenses in life, health and property (up to a hundred million dollars). Therefore it will be payed for by taxpayers' money, what else? As soon as the stuff dries up, it turns into wind-blown fine powder, difficult not to inhale. The problem with calling CO2 a pollutant just like any immediately dangerous stuff is it makes impossible to enact compulsory liability insurance policies covering all possible damages for corporations trading in potential pollutants. This is why blurring the legal notion of "pollutant" by including harmless substances by sweeping generalizations is prime interest of corporate lobby groups. Here, in Hungary we have 50,000,000 tons more of this mud stored in aging repositories, declared safe for the time being, nevertheless property prices in those areas are plummeting like stone. Relief donations can be sent to: National Saving Bank, Budapest IBAN: HU7511702036-20707637-00000000 SWIFT: OTPVHUHB
  40. Climate Cherry Pickers: Falling sea levels in 2010
    So what I might do by way of attempting to demonstrate a change of the rate of change would be to do some multiple regression modeling until i got a reasonable and valid fit. Then I would start entering and removing variables from the model to see if the predictive power changes. Specifically I'd examine the residuals of the model and look for systematic changes in heteroskedascity at the end of the time-series when omitting key variables. A specific pattern of residuals will indicate an acceleration of the line of best fit gradient. Three problems here: Firstly the effect size may be too small over a short period of time relative to the other signal, and noise in the data for this approach to be worthwhile. Secondly this is a quantitative social scientist's approach to what is a physical problem, so there may be better approaches more well suited to this domain. Three, this would be a day or two's work at least, after curating the data (so give it a week) so it ain't going to happen in a science blog.
  41. Climate Cherry Pickers: Falling sea levels in 2010
    BP #97 "Departure from a linear trend may not be significant, but it is not accelerating either." Well strictly speaking you're making that conclusion due to a limitation in the methodology of regression (see this post which demonstrates the staggering lack of power in these univariate not-corrected for the limitations of time series procedures). In order to demonstrate a change to the rate of change you have to use more sophisticated methods than simple two variable regression.
  42. It's freaking cold!
    Tom Loeber, so some people made daft comments in the past (going back to Columbus's day), therefore you don't trust anyone ? How do you trust even your own conclusions ?
  43. How do we know CO2 is causing warming?
    @adelady My bad on understanding your analogy then. Having said that, the paper did get values for the skin temperature with varied downward LW radiation though. I offer the following chef analogy. A chef is asked whether he can cook for large groups and he says sure and cooks a single plate to "prove" it. The point of this is that he has shown he can cook the meal so its almost certain he could cook 50 of them...but can he do it fast enough to be successful?
  44. It's freaking cold!
    Tom Loeber wrote : "I find at times experts have been quite mistaken in a major way, a majority of them." Do you indeed ? Care to name a few of those times ? Tom Loeber wrote : "I think more important than depending on hear-say and the like, attempt to get a grasp of the data yourself and draw your own conclusions. Quite right, partly, I think. Don't rely on hear-say, definitely (and that includes media reports, etc.) - rather, rely on the experts, the expert studies and the science. Draw your own conclusions if you wish (and there are many so-called skeptics on here who certainly do !), but don't think that your conclusions are as valid as anyone elses, especially if your conclusions go against the conclusions of the science.
  45. Climate Cherry Pickers: Falling sea levels in 2010
    BP, Please respond to the questions that I posed to you at #89. Thanks. And your reference to Church is a red herring, and I would argue that you are misrepresenting their findings with the quote that you chose to produce here. How about we quote the relevant part of their abstract? "While sea levels have varied by over 120 m during glacial/interglacial cycles, there has been little net rise over the past several millennia until the 19th century and early 20th century, when geological and tide-gauge data indicate an increase in the rate of sealevel rise. Recent satellite-altimeter data and tide-gauge data have indicated that sea levels are now rising at over 3 mm year-1. The major contributions to 20th and 21st century sealevel rise are thought to be a result of ocean thermal expansion and the melting of glaciers and ice caps. Ice sheets are thought to have been a minor contributor to 20th century sea level rise, but are potentially the largest contributor in the longer term. Sea levels are currently rising at the upper limit of the projections of the Third Assessment Report of the Intergovernmental Panel on Climate Change (TAR IPCC), and there is increasing concern of potentially large ice-sheet contributions during the 21st century and beyond, particularly if greenhouse gas emissions continue unabated." Also, Church did not, as far as a can see, simply extrapolate a linear line to estimate sea levels circa 2100. The sea-levels circa 2100 were based on model projections with and without dynamic processes. Their Fig. 6 shows that sea levels are rising faster than predicted in TAR. Actually, it seems that each time the estimates are updated for sea levels they are higher , not lower, then previous projections. For example, the recent projections made by Vermeer and Rahmstorf (2009). Let me remind you BP, as far as changes in SL goes, it is still very early days, and the rise is not going to suddenly stop circa 2100.
  46. Climate Cherry Pickers: Falling sea levels in 2010
    kdkd@91, Sorry for the confusion. That is entirely my fault kdkd. I messed up when I was calculating the regression models and requested that the moderator remove the erroneous information. Time is an issue-- having to look after the little ones today. But I promise to get back to you ASAP. In the meantime, I have plotted the residuals and I cannot see anything that justifies using a quadratic model versus a linear model.
  47. We're heading into an ice age
    In the July 2003 pdf Doug Bostrom linked to, "Are Noctilucent Clouds Truly a 'Miner's Canary' for Global Change?"
    it is stated "Unambiguous observations of NLC go back to the summer of 1885,when NLC appeared above western Europe with a brightness and latitudinal extent which has never been reached again." As far as I can tell from the NASA graph I post above, their first siting was surpassed in the 1950s as well as the 1960s for the extent of that graph. Why does the pdf misrepresent the situation? How come it only considers its hypothesis that noctilucents play no role in climate change on less than a third of the time they have been observed? Isn't the fact that there is no record of them being observed prior to the industrial revolution of significance?
  48. Global warming is accelerating the global water cycle
    Syed et al. say that the trends of global mean discharge are statistically significant. It is surely true. But, the values they obtained for different periods vary wildly without understandable reason. As I look at their Fig. 2A, my impression is that there is no consistent trend. The part of year 1993-2005 of the figure which Charlie A quoted from Trehberth's paper is similar in a sense that there is no obvious trend, though its year-to-year peaks and valleys do not always match those of Syed et al. On the other hand, my impression of Syed et al.'s Fig. 2B is that the global mean evaporation from the oceans has a consistent positive trend in the 1993-2006 period, though I am not sure if the trend is attributed to enhanced greenhouse effect or multi-decadal variability. Evaporation from the ocean is a dominant part of the global total evaporation, which represents the largest scale of the global water cycle. On the other hand, the global total river runoff represents the partition between land and ocean -- one step smaller scale than the global mean. It seems (to me) that the trends in the actual water cycle is simpler in the global scale than in more detailed scales.
  49. It's freaking cold!
    I quite agree muoncounter. In considering climate, not just years or tens of years or even thousands of years, we should also consider hundreds of thousands of years as necessary because it shows a repeated oscillation that if not considered could lead to missing cues for worthwhile strategy determination. I find at times experts have been quite mistaken in a major way, a majority of them. I think more important than depending on hear-say and the like, attempt to get a grasp of the data yourself and draw your own conclusions. Always realize we can only hold onto an opinion. Socrates is quoted as having said "True knowledge exists in knowing you know nothing." Thank you for the reasonable comment moderator. I will attempt to post to that other thread again the egregious false claim made in the paper posted on down-playing noctilucents again.
  50. Skeptical Science housekeeping: Comments Gluttony
    I'd be interested in seeing a guest post by a skeptic only if it was rooted 100% in peer reviewed literature, assiduously written to claim nothing not found in conclusions directly traceable to peer reviewed work. That or if it was written by someone in a very narrow bracket probably best characterized by Dr. Roy Spencer. The last thing we need is to hear yet another bunch of disconnected opinion. Failing that, we'd be seeing a replication of ill-conceived fairness as practiced by newspapers and the like. Monckton redux.

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