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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 115051 to 115100:

  1. We're heading into an ice age
    Erin, If you click on the link for the source of figure 4, the author of the article addresses this. It has to do with expected low insolation variability for the time being. It is worth noting that this agrees with some predictions, but disagrees with others. The primary thing to take away from the study is that if we continue to release large amounts of CO2, then we could potentially delay the onset of glaciation indefinitely. McCloud, the 5000 gigatonnes CO2 emission is based on an estimate of how much we could potentially release if we burn all available fossil fuels. Thus, with the calculated forcing of that much CO2, we see an upper limit of 4 degrees warming. This study may not be the best source for looking at future temperature anomalies, however, because its purpose is to look at the potential for preventing the next glaciation. The scope of the study really isn't to make precise temperature anomaly predictions, but rather predict how much glaciation will be delayed under different emission scenarios. I would suggest clicking on the link to the study. As for your second question, yes there is potential for a positive feedback here. As water warms, its capacity for storing CO2 decreases, which will eventually lead to the oceans actually releasing CO2 as opposed to taking it in. I am fairly sure that most climate projections take this into account already.
  2. gallopingcamel at 14:11 PM on 17 July 2010
    Hotties vs Frosties?
    There are enough large wind and solar projects out there (e.g. California, Denmark, Germany, Spain) to allow economic analyses to be made. Here is an analysis relating to Spain: http://www.juandemariana.org/pdf/090327-employment-public-aid-renewable.pdf One of the major selling points for renewables is that "green jobs" will be created. Dr. Calzada's analysis shows that for every "green job" created 2.2 other jobs are lost. Given that the majority on this thread are in favor of renewables and against Nuclear Power Plants, can you cite any projects that produce power at reasonable prices absent subsidies?
  3. Monckton tries to censor John Abraham
    Good post by Brian Angliss.
  4. Part Three: Response to Goddard
    Robert Way at 09:33 No, i bought up the co2, because the Antarctic glaciation is a different kettle o fish than the northern hemisphere glaciations... there is a continent sitting on the pole. And i wouldn't expect it to behave similar to say green land... i wouldnt be betting on long term trends in Antarctica based on co2 alone. But time will be the judge on that. Also going back 45mybp TSI would not have significantly off set those elevated co2 levels... its not that long ago in the larger scheme o things.
  5. Rob Honeycutt at 10:55 AM on 17 July 2010
    Part Three: Response to Goddard
    To add to that reply to Joe Blog... You also have to look at the rate of ice mass loss relative to all the other data related to global warming. When you look at any of the the above charts they paint an eerily similar curve to all the other charts. CO2 levels, global temps, etc. If these charts regarding ice mass loss were significantly dissimilar you might consider that something else is afoot. But the fact that they mirror all the other indicators of AGW you would have to be completely disingenuous to ignore a strong potential relationship.
  6. Part Three: Response to Goddard
    Joe Blog, to simply state that CO2 was 1000ppm at that time is a bit disingenuous don't you think? I think you should have perhaps included the phrase about solar being less and milankovich orbital cycles too. For me it doesn't make sense why you brought up CO2 unless you were trying to make a deceptive remark. But regardless, you're partially correct in your assessment. Oceans are causing most of Antarctic mass losses. But it is not a change in ocean currents but rather oceanic warming mixed with wind changes that bring the warmer water in. Why is the water warmer? Who knows, but I think it is fair to say that ocean waters have warmed significantly and that human influence must be considered during attribution. Also note that the West Antarctic ice sheet is a marine ice sheet so it would of course have a dependence more upon oceans than other regions.
  7. Part Two: How do we measure Antarctic ice changes?
    Okay dude, you have to tone it down a little. The thomas et al. study I pointed to had nothing to do with antarctica but was rather about Greenland, it is entitled "A comparison of Greenland ice-sheet volume changes derived from altimetry measurements " and concludes that Radar alimetry overestimates gains at high altitudes by 75 Gt year. The Pfeffer et al. 2008 study is a good study. And it concludes that sea level rise will be greater than IPCC median predictions. I don't know why you even brought it up? Whose talking about sea level. Regardless Vermeer and Rahmstorf is newer and shows relation between temperature and sea level which is important. Maybe that's why they put it in? I haven't really seen Pritchard et al. 2009 being dated differently but sure. If you want to discuss mass balance estimates you can start by checking out the figure at the bottom of here http://www.skepticalscience.com/Part-Three-Response-to-Goddard.html About the IPCC (2007). Steig et al. 2009 conclude that Antarctica has warmed, particularly western portions. The IPCC is a meticulous document but also a political one and tends to not include the latest literature. IPCC models on ice losses do not include ice dynamical processes and thereby have been proven wrong time and time again as both Antarctic and Greenland mass losses are extensive. (See chen et al. 2009, Velicogna 2009, Rignot et al. 2008a, Rignot et al. 2008b, Cazenave et al. 2009 and so on). With all due respect. You aren't really making a whole lot of sense. You are throwing all kinds of evidence out there which only suggests that you are cherry picking the literature.
  8. Part Three: Response to Goddard
    angliss, I didn't really catch on. Kinda just glanced at it. Sorry for the confusion. On the bright side, the first link actually was kinda interesting regardless.
  9. michael sweet at 08:06 AM on 17 July 2010
    Watts Up With That concludes Greenland is not melting without looking at any actual ice mass data
    Peter, Your posts always raise the level of discussion. Thank you for informing the rest of us. Is the decrease in heat in the first 100 meters from a La Nina? (I cannot penetrate the paywall). I would have thought surface heat content would have risen since ocean surface temperatures are currently so high. It is amazing how rapidly the science is advancing. The paper I cited as saying heat had not passed 3000 meters is only two years old. OHC is a difficult problem. Hopefully the scientists working on it will continue to rapidly advance the state of knowledge. Are you the Peter Hogarth who studies sea grass?
  10. Part Three: Response to Goddard
    Interesting article. So, im reading this as ocean currents being the predominant driver in calving events in Antarctica? Makes sense, ice sheets first formed on there when co2 was around the 1000ppm, So the ice state there may be more driven by ocean events/ responses. http://geosci.uchicago.edu/people/Bromirski_Serg_MacAyeal.pdf This link here is on infragravity waves, and their inferred contribution to calving events in Antarctica.
  11. John Russell at 07:29 AM on 17 July 2010
    Does partial scientific knowledge mean we shouldn't act?
    Riccardo #13 You miss my point. Of course I could look up the source of the quote myself -- in fact I did -- but if we are to win the argument that AGW is happening and the world should act on it, it's important to ensure that there is a real difference in the way the argument is presented on sites such as SkSc, as compared with the way the counter argument is presented on sites such as WUWT. I raised the point to highlight this. Total PERCEIVED transparency is the only option.
  12. Part Three: Response to Goddard
    Robert - I was trying to make a joke at Goddard's expense, actually. I guess it fell flat.
  13. Monckton tries to censor John Abraham
    I propose we stop calling him "Lord.." and start calling him "Chris". :)
  14. Part Three: Response to Goddard
    Nice graphs! The big run up in the runoff curve in the mid-90s which matches the polar temperature anomaly uptick here. (Sorry for linking my own article). SMB is negative (presumably losing mass), but Precip/Runoff is positive?(or is that a measure of the quantity of runoff and so not meant to have a sign). I would of thought massice lost = massice calving + massice melting + masswater evaporating + massice sublimating. But it would appear that sublimation isn't a big factor.
  15. John Russell at 04:28 AM on 17 July 2010
    Part Three: Response to Goddard
    NickD: With regards to your question about warming and the loss of Antarctic ice, you might find it useful to take a look at the 10th of the popular sceptical arguments Antarctica is gaining ice. Thanks for the question. It's important that on this site real sceptics and 'don't knows' can find answers to their questions about climate science, explained with civility. Many people who use this site as a source of information -- like me -- started out being sceptical but, like all people with open minds, we were persuaded by the mass of evidence and clearly-obvious consensus among the scientific community. Best wishes.
  16. Facebook page to support John Abraham
    quokka #22 Great post at Eli Rabett's. Really worth a read. Thanks.
  17. Part Three: Response to Goddard
    Van den Broeke et al. (2009) nicely break down Greenland's mass balance into its various components, including the effects of precipitation, runoff, sublimation, and discharge. John discusses that paper in his blog post Why is Greenland's ice loss accelerating? Here's a figure showing how total mass balance is being driven by both surface mass balance and discharge: Greenland mass balance and its components Surface Mass Balance (SMB) and Discharge (D). Before 1996, D and hence SMB - D, are poorly constrained and therefore not shown. and here's one that breaks down surface mass balance into its components: Surface Mass Balance (blue) and its components precipitation (red), runoff (orange) and sublimation (green).
  18. Facebook page to support John Abraham
    That too, yes. :)
  19. What's in a trend?
    garythompson, just a caution about Chylek ... one of his recent papers is pretty much the ultimate example of erroneous results created by inappropriate selection of individual data points (see here and here). Problems with one paper don't necessarily carry over into others. But I would probably be a bit more careful when reading a new paper by Chylek, given that history.
  20. Facebook page to support John Abraham
    JMurphy, you're right ... it looks like there's something wrong with the way the Search box is interacting with the database. Until John gets this straightened out, I guess Googling Abraham site:skepticalscience.com is the way to go. DarkSkywise, I'd say this is a nice illustration of how different methods applied to the same data set (the database of posts) can give inconsistent results even when nobody is deliberately tampering with the data!
  21. garythompson at 03:16 AM on 17 July 2010
    What's in a trend?
    Humanity Rules, John or Muoncounter: I would like to read the Petr Chylek paper that HR speaks of in this comment section. Like Muoncounter I have never seen a good explanation why the two poles appear to have temperature trends going in different directions and this sounds like an explanation I have not heard before. Maybe John can post some portions on the web (unless that violates copyright laws or something like that). Many thanks in advance!
  22. Facebook page to support John Abraham
    Alternatively, you can just type "Abraham" in the Search box in the upper left corner of the page, and they all show up. Oh yes, that search box. (Speaking about hiding in plain sight.) :D But it's still a nice example of different researchers using different means and data sets, and all arriving at the same conclusion (i.e. "John Abraham's posts are real and do exist"), just like AGW.
  23. Facebook page to support John Abraham
    Ned, how come when I type in 'Abraham' (without the quote marks, or whatever they're called), I only get : Abraham reply to Monckton Facebook page to support John Abraham Monckton tries to censor John Abraham Podcasts interviews and Monckton bashing
  24. Part Three: Response to Goddard
    Angliss, Greenland does have surface melt. see http://www.nasa.gov/centers/goddard/news/topstory/2007/greenland_recordhigh.html or http://earthobservatory.nasa.gov/Features/Greenland/Images/greenland_melt_pond.jpg Lots of melting there actually...
  25. Part Three: Response to Goddard
    Muoncounter - Greenland doesn't have surface melt, but it does sublimate! ;)
  26. Part Three: Response to Goddard
    Sean A, I understand that I should of perhaps gone through glacial flow mechanisms but ultimately part one covers some of it and I thought that would drag it out quite a bit to have to explain all the different mechanism for movement and everything that affects it.
  27. Part Three: Response to Goddard
    muoncounter, Skeptics do often seize on the wingham et al. 2006 study. But its easy to refute as Thomas et al. 2008 proved that the satellite technology used in wingham et al. (radar altimetry) has a bias towards showing less ice losses.
  28. Facebook page to support John Abraham
    Alternatively, you can just type "Abraham" in the Search box in the upper left corner of the page, and they all show up. I use that search box all the time. It's a handy way of finding things when you want to search only the posts and not the comments (a google search for a commonly used term would bring up many threads in which that term might not have been used in the top post). For example, using John's search box at upper left, a search for "icesat" shows five posts. A google search for "icesat site:skepticalscience.com" shows about 15, mostly people mentioning it in the comments. Of course sometimes you're looking for stuff in the comments, in which case google is the way to go.
  29. Facebook page to support John Abraham
    How well the University of St Thomas has acted should be applauded. Eli Rabett has published their correspondence here: A humble suggestion - support the University of St. Thomas
  30. Part Three: Response to Goddard
    Nicely written and very well-documented! Your last figure (6) does leave a window open: If I was a skeptic, I would seize the WH estimate and say 'Aha! No consensus!' NickD #4: Re "I am left with the impression that melting glaciers and ice sheets (specifically Antarctica and Greenland) are not necessarily evidence of global warming," see the line in Robert's text: "In Greenland, calving represents between 40 to 60% of total ablation (ice loss) whereas in Antarctica it represents a whopping 90% of total ablation." That suggests to me that Greenland's ice loss is 60-40% melt. Goddard's 'argument' that ice doesn't melt because the air temp is below freezing wouldn't apply; check the current temps in Greenland here (I just looked at Thule where its a comfortable 6C).
  31. Part Three: Response to Goddard
    (Although some of the comments that appeared while I was commenting do help.)
  32. Part Three: Response to Goddard
    Nice series of articles. Can I suggest a follow-up post covering the basic science of glacial flow? This isn't quite a sufficient explanation: "Take for example that many of these locations are regions where ice is channelled from the interior of the ice sheet to outlet glaciers causing much higher velocities. Another thing to consider is that where the depth of ice is extremely thick, the ice can provide insulation and actually heat the bottom of the ice leading to basal lubrication and increased ice flow."
  33. Part Three: Response to Goddard
    Robert, I do appreciate the post and replies. It's always enjoyable and beneficial when those with extensive knowledge make themselves available for questions :) I certainly understand the point of the posts was not to prove global warming. You were addressing specific and incorrect claims, a generally thankless task! As I said, I was playing a bit of Devil's Advocate ;) Keep up the good work.
  34. Part Three: Response to Goddard
    Skywatcher, Yeah i was going to talk about that actually but then i'd have to get into the methods of movement and all that stuff. Ultimately it would lead to grounded below sea level portions and so on. I just thought that I had to cut it off somewhere. haha. Yeah I probably should of brought up the inland propagations but I found it hard to find studies other than the removal of buttressing ice shelves that really showed distinct evidence of it. I can think that some radar interferometry studies have found an inland increase of velocities but to generalize and say it could occur in all of those places is a bit of a stretch without having an idea as to the topographic constraints in the regions.
  35. Part Three: Response to Goddard
    Well NickD, To be absolutely honest Glaciologists and professionals in glaciology do not focus on attribution of warming. Whether warming is Anthropogenic or not, individuals in this field just try to report what is happening and what will happen under certain scenarios. I can tell you this, a warming planet will result in more ice being lost. If we cause the planet to warm further, more ice will be lost. This post wasn't meant to prove that AGW causes ice sheets to lose mass, it was to educate and disprove some common misconceptions on the blogosphere. But I can summarize it like this for you. Greenland is losing ice because of surface melt, surface meltwater reaching the bed of the glacier speeding it up, melting/collapse of ice shelves holding back glaciers and warm water causing grounding line retreat. There is one key variable to consider there, all those processes are induced and intensified by increased warmth. Antarctica is a bit of a different story. Ocean waters are causing grounding line retreat and bottom melt of glaciers which in turn can cause accelerations. Air temperatures and ocean temperatures are combining to remove some ice shelves which hold back glaciers also. The warm water coming in is the result of what is thought to be a change in wind patterns. Wind patterns change with warmth and so does the distribution of air masses. Any more questions, just ask.
  36. Mighty Drunken at 01:47 AM on 17 July 2010
    Does partial scientific knowledge mean we shouldn't act?
    To post #35. Your reaction to the story on Erik Verlinde paper is interesting and has a bearing on the public's perception of science and therefore climate change. His paper “On the Origin of Gravity and the Laws of Newton” is interesting and not contrarian, it is simply a different way at looking at the origin of gravity - it also may be completely wrong as he says himself. To someone not well versed on the subject matter and how it is reported by the media can lead people to think there is a bunch of physicists who don't believe Einstein's theory. Sounds familiar? If Erik Verlinde approach gives the same predictions as Einstein's then science won't really care which one is correct. The question is do they match experiment? Lookup "Interpretation of quantum mechanics" to see a similar debate. Which one is correct is more philosophically interesting then it is scientifically important.
  37. Part Three: Response to Goddard
    Nice summary of Antarctic ice losses. I would add that one of the important processes allowing fast flow are weak debris/till covers at the beds of ice streams. I remember a presentation about the evolution of these covers at the Siple Coast streams, but can't recall the reference to confirm. The other goddard mis-info that really annoyed me was the idea that acceleration at the coast could not propagate inland quickly to drive thinning - blatantly totally wrong. Scambos et al (2004) provides an example on a smaller scale from the Antarctic peninsula (Larsen B shelf collapse). The acceleration happens right away both at the coast and inland in response to the change, with a gradual increase as the system heads towards a new equilibrium.
  38. Part Three: Response to Goddard
    If I can play a bit of Devil's Advocate here, and speaking purely as a layperson who has a very basic understanding of most of your posts, I am left with the impression that melting glaciers and ice sheets (specifically Antarctica and Greenland) are not necessarily evidence of global warming, as much of the melt is due to factors generally unrelated to temperatures. Is this accurate? I'm trying to understand for myself, but also I am trying to put myself into the shoes of some who might read these posts and be left with the same impression and would subsequently cite your posts to argue that there's nothing we can do about Greenland and Antarctica melting. You get the idea...
  39. Facebook page to support John Abraham
    Since everybody is posting urls anyway, I might as well do the full versions: june 2: Abraham shows Monckton wrong on Arctic sea ice june 4: Monckton Chronicles Part II: Here Comes the Sun june 6: Abraham reply to Monckton june 8: Monckton Chronicles Part III: Acid Reflux june 11: Monckton Chronicles Part IV: Medieval Warm Period (the preview worked, hope the submit works too!)
  40. Facebook page to support John Abraham
    tobyjoyce, Part I is accessible from Part II, and is here : Part I
  41. Facebook page to support John Abraham
    Got some of the URLs tangled above. However, the point is made - these have not been removed. Passing Wind just could not find them, but they are difficult to find.
  42. Facebook page to support John Abraham
    Hare are 3 of Profesor Abraham's posts which did not come up with the Search command .. I used Google. Not sure what happened to Part I. Part II Part II ,a href="http://www.skepticalscience.com/Monckton-Chronicles-Part-IV-Medieval-Warm-Period.html"> Part III
  43. Watts Up With That concludes Greenland is not melting without looking at any actual ice mass data
    Ken Lambert wrote : 1970 is the era when we were going to have the next ice age and CO2GHG warming had not been pressing. Not true, and you've been on this site long enough to know. Selective memory ? "1970s ice age predictions were predominantly media based. The majority of peer reviewed research at the time predicted warming due to increasing CO2." Or were you trying to refer to a specific event in the year 1970 ?
  44. carrot eater at 00:10 AM on 17 July 2010
    Part Three: Response to Goddard
    Some little editing: The sentence with "ice cannot flow at high speeds when air temperatures are. " needs to be completed somehow.
  45. It's not bad
    A bit far fetched maybe, but AGW is causing more space junk to threaten satellites and spacestations. The cooling of the stratosphere causes the atmosphere to contract which lowers the density of the upper atmosphere. This reduces drag on debris which therefore stays longer in orbit. http://www.newscientist.com/article/mg20627663.000-climate-change-is-leaving-us-with-extra-space-junk.html
  46. Facebook page to support John Abraham
    Anymoo, I've joined Facebook (I had planned not to, being a member of far too many sites already), so I could become a supporting member of Prawngate. On the plus side, having just made such a Large Personal Sacrifice (oh dear, there are the first friendship requests pouring in already... what is this? an ambush? shoo!), it'll probably be Extremely Appreciated, which is nice. :)
  47. Watts Up With That concludes Greenland is not melting without looking at any actual ice mass data
    Ken, Unless you have new information (i.e. new peer reviewed studies which support your position), your argument (putting all of your eggs in one basket more like) is still not valid. This is because the one thing we can be sure of about the heat balance measurements are that significant components are insufficiently precise over short durations to measure small changes with sufficient accuracy to draw strong conclusions.
  48. Arkadiusz Semczyszak at 23:49 PM on 16 July 2010
    Part Two: How do we measure Antarctic ice changes?
    Robert Way “Thomas et al. 2008 ...” Whether it's this papers: A DOUBLING [?] in snow accumulation in the western Antarctic Peninsula since 1850.? There is such (a favorite of skeptics) fragment: “Annual accumulation has more than doubled in the last 150 years: the mean for 1855–1864 was 0.49 mweq y-1while for 1997–2006 it was 1.10 mweq y-1. At the beginning of the record annual accumulation is relatively stable until about 1930 when it begins to increase steadily. Following a slight reduction in accumulation in the late 1960s, the most rapid increase occurs in the latter part of the record with the mean accumulation rate from the mid-1970s onwards increasing to 0.95 mweq y-1. Note that for the post-1980 period even the lowest annual accumulation values are still greater than the highest accumulation values from the first half of the record (1855–1924).” IPCC 2007 report : “Antarctic sea ice extent continues to show inter-annual variability and localized changes but no statistically significant average trends, CONSISTENT WITH THE LACK OF WARMING REFLECTED IN ATMOSPHERIC TEMPERATURES AVERAGED ACROSS THE REGION” ; “Current global model studies project that the Antarctic ice sheet will remain TOO COLD for widespread surface melting and is expected to gain in mass due to increased snowfall.” Of course, growth of the ice sheet may well be evidence of warming, but then we have nothing to fear when it comes to sea level. None of the methods described here are not detailed enough to authorize such a declaration that: Antarctic ice really quickly lose land (do you really lose?). In any case I will add that this works like this: Extensive dynamic thinning on the margins of the Greenland and Antarctic ice sheets, Pritchard, 2008(9? - is variously dated), suggesting that the same is happening in the Arctic and Antarctica is the only way that: „... Amundsen Sea embayment of Antarctica, thinning exceeded 9.0 m yr-1 for some glaciers.”; an example of a typical "c. p.”. For me it is not "pure" science - even to discuss. For "cool" temperature of the discussion (in Poland - the heat wave) I propose: Kinematic Constraints on Glacier Contributions to 21st-Century Sea-Level Rise, Pfeffer et al., 2008: “We consider glaciological conditions required for large sea-level rise to occur by 2100 and conclude that increases in excess of 2 meters are physically untenable. We find that a total sea-level rise of about 2 meters by 2100 could occur under physically possible glaciological conditions but only if all variables are quickly accelerated to extremely high limits. More plausible but still accelerated conditions lead to total sea-level rise by 2100 of about 0.8 meter. These roughly constrained scenarios provide a "most likely" starting point for refinements in sea-level forecasts THAT INCLUDE ICE FLOW DYNAMICS. [!!!]” Well, well ... For me this is very strange that the latter paper is not cited in: The SCAR Antarctic Climate Change and the Environment (ACCE) report (Antarctic Climate Change and the Environment – An Update, 2010); and only: Vermeer and Rahmstorf (2009): Global
sea
level
linked
to
global
temperature., and Velicogna (2009). However, the SCAR report is very, very interesting ... and should "give a thought" ...
  49. Part Three: Response to Goddard
    Ice leaving Antarctica and Greenland gets distributed to lower latitudes, where it increases the earth's moment of inertia. Consequently, the earth's rotation rate should decrease. Has anyone tried to use the earth's rotation rate to measure the loss of (non-floating) ice from polar regions?
  50. Watts Up With That concludes Greenland is not melting without looking at any actual ice mass data
    KL #57 = OOps Post#50.

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