Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings

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.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  1941  1942  1943  1944  1945  1946  1947  1948  1949  1950  1951  1952  1953  1954  1955  1956  Next

Comments 97401 to 97450:

  1. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    Snowhare #20 I don't know about "fairly random" Nephi, Utah, but I think most people would take note if, say, a forecast high for the next day was 80F and it turned out to be 92F. But, please note that I very much agree with what I think is a main point of the post, that a rise of 7C in the global average is enormously more significant than a day to day variation. Sorry if I didn't make that clear.
  2. Monckton Myth #7: Snowjob
    It will be fantastic to the records if the NASA guys can recover the NIMBUS satellite data. It could add data as far back as 1964!
  3. Monckton Myth #7: Snowjob
    Monckton has been promoting this canard about winter N. Hemisphere snow cover trends refuting AGW for some time: "There has been no decline whatsoever in the total global extent of sea ice since satellite records began. New records for the extent of northern-hemisphere snow cover were observed by the satellites in the winter of 2001 and again in 2007. This year, many ski resorts are opening early as Arctic weather strikes. Many temperature stations in the northern hemisphere recorded record low temperatures in October/November 2008." [Here on Tuesday, 09 December 2008 19:51] What is more, he could have not made that claim about the 2001 and 2007 extents being records without having looked at all the data. So he cannot plead ignorance. Furthermore, as the Rutgers data show, Monckton's claim that the N. Hemisphere snow cover in the winters of 2001 and 2007 were record highs is demonstrably false. Unless, he was referring to a specific month-- either way he has deceived the reader. According to the Rutgers data, 2001 and 2007 were not spectacular years for N. Hemisphere snow cover, not even close. According to Rutgers the record high N. Hemisphere snow cover extents for the individual Boreal winter months since 1979 are: December 1985@ 45.99 million km^2 (followed by 2009 and 2010) January 1985 @ 49.87 (followed by 2008 and 1979) February 2010 @ 48.39 (followed by 1980 and 1985) The Rutgers data go back to late 1966, in which case the records are: December: 1985 (followed by 1970 and 2009) January: Unchanged February:1978 (followed by 1972 and 2010)
  4. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    Another useful analogy perhaps to explain the difference between weather and climate: a gas. It is impossible to know the exact position and speed of every molecule in a gas, but it is perfectly possible to describe it’s behavior in macroscopic terms (temperature, volume, pressure), and to use that knowledge to generate electricity via a thermodynamic cycle. The knowledge of the microscopic scale isn't necessary to successfully predict the behavior on a macroscopic scale.
  5. A Flanner in the Works for Snow and Ice
    Jim And my background is in Mechanical Engineering. After several years looking fairly intensely at AGW my position firmed up quite strongly, based particularly on the thermodynanmics of present circumstances and the deep paleoclimate record. I accept that there is still uncertainty about the magnitude of the future warming, and I wouldn't be at all surprised if some of the more detailed prediction made turn out incorrect to some degree such as hurricanes for example - frequency vs intensity. What convinces me is the larger planet-scale phenomena. And the aggregate temperature rises predicted for later this century are terrifying. A world with that much warming isn't a world that can feed 9-10 Billion people. I hope your son is well.
  6. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    I am often amazed at the accuracy of weather forecasting; it is not uncommon for the prediction be accurate down to the hour of precipitation onset. I find it instructive to read the 'technical discussion' offered by the weather service here in the US. This discussion will evaluate multiple models, indicate when they diverge and when they agree, and even offer comments on how small changes in storm path may result in large changes in weather outcome. It may be beyond the scope of a short discussion, but I think the accuracy of weather forecasting up to 10 -14 days in advance strengthens my confidence in climate models. Here is today's discussion for my area: http://forecast.weather.gov/product.php?site=NWS&issuedby=LOX&product=AFD&format=CI&version=1&glossary=1 It is not particularly interesting right now, but can give a very good idea of the confidence of predictions.
  7. A Flanner in the Works for Snow and Ice
    @ 23 & 24 Then you may want to start following Neven's Sea Ice blog for the best in real-time coverage and cutting edge commentary of the Arctic melt season... Keep an eye out for Artful Dodger's posts; he's a sharp one... The Yooper
  8. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    The Ville at 23:32 PM on 24 January, 2011, re "They don't think that reliability is 'engineered' and they just get the engineered result." This does apply to weather forecasts as there is considerable variation in the quality of weather forecasts available and it can be a case of getting what you pay for. For most people, probably including most who post here, weather forecasts are of academic interest and I doubt that few, if any, would be subscribing and paying for private forecasting services. However those who have a vested interest in the future weather, be it those in the agriculture sector, or insurance companies offering rain insurance or the like, do not rely on the free forecasting services even if they are being supplied by the major forecasting bodies who generally have the resources and authority of their government backers behind them. Instead, and this is where the "engineered reliability" comes in, they will instead rely on those professional forecasters whose approach and ability to think outside the box when it comes to compiling forecasts, has them years ahead of the major bodies who are normally considered the authority. Many jokes are made about the record of our own BOM and CSIRO forecasts, as are the UK's Met office recent record, but people will joke about something that appears not to be paid for directly out of their own pocket. However when someone is paying hundreds or thousands of dollars for reliable forecasts, where the outcomes and gains or losses can be measured in hundreds of thousands Dollars, then one can be sure that the "engineered reliability" is carefully taken into consideration, and that is what private forecasting services are able to demonstrate. There is no doubt that as time progresses the forecasts from the major services has improved, but so has those of the private services, the lag appears to me to be at least a decade, that being they time between new indicators being identified and utilised by those operating at the leading edge, and the main stream bodies encumbered with their bureaucracy and their need to serve their political paymasters.
  9. A Flanner in the Works for Snow and Ice calculations
    MarkR: I have an alternative idea. Flanner et al claim that cryosphere albedo feedback is larger than the models have. But those models still track real temperatures (more or less), right? That means that if we include the "correct" feedback, then they (or most of them) would be running too hot, no? Isn't it therefore more likely that something else in the models is off a bit (e.g. aerosol forcing, other feedbacks)?
  10. Monckton Myth #7: Snowjob
    #6: "Skeptics too often produce...". Skeptics don't, _denialists_ do. Skepticism is essential for science, and I don't think we should let the meaning of that word become corrupted. That would really be a lasting victory for the denialists. And, a skeptic who is not skeptical also towards his own ideas is no real skeptic, rather some kind of polemic. BTW, for a prolonged time, winter NH snow cover may increase under global warming, the increase in air moisture content thus generating a (local) negative feedback, in part via albedo. But I don't think this will be very significant for the overall warming process, because the "lost" radiation is relatively weak - few insolation hours and low angle. (These days, I use the solar collector, Norway, mostly for feeding the heat pump, rather than direct heating - that's the best use of it. But in March, the situation will have changed dramatically.)
  11. A Flanner in the Works for Snow and Ice
    @23 Gordon: The most annoying thing is that we will be ejected from the game and will never find out the result.
  12. Monckton Myth #7: Snowjob
    Dana @8, "perhaps just being careless." You are being far too generous. Monckton is fully capable of talking about paleo climate, historical temperature record etc.. He knows these data, he makes a livelihood going around the world speaking to them. So I think it highly, highly unlikely, that Monckton happened to simply "forget" about some inconvenient data points. Besides, even if Monckton did err by chance, then Anthony Watts should have caught it and had him change it ;) What would clarify this is to determine what time window for snow cover Monckton has shown in his slides. I'll get back to you should I find anything.
  13. Monckton Myth #7: Snowjob
    Tom #6 - nice sleuthing. Here is the Goddard plot in question: Since Goddard omits the data prior to 1989, had he been using this WUWT post as a reference, Monckton would not be aware that 1978-79 had the record NH snow extent. I'm still not sure how Monckton would have confused the "record" of 2009-10 with 2008-09, perhaps just being careless.
  14. Monckton Myth #7: Snowjob
    I posted too soon. I have just discovered that the NSIDC records on snow coverage start in November of 1978, whereas it was Dec 1977 - Feb 1978 that set the record on the Rutgers data. Monckton may not have been dishonest in this case (beyond cherry picking winter).
  15. Monckton Myth #7: Snowjob
    Following up on this article with a few google searches, I think I may have found the source of Lord Monckton's error. In particular I found an article at Watt's Up With That called "Northern Hemisphere Snow Extent Second Highest on Record". (Google it if you want to see it. I don't link to trash sites.) In this article, Steve Goddard produces a graph of NH winter snow extents with a clear upward trend. Looking closer, it becomes obvious the trend in introduced by carefully selecting a start year of 1989. (Sceptics to often produce odd trend lines in graphs by because of the start date for it to be other than carefull selection.) Had the potty Lord seen an earlier version of the graph, it would explain his belief that the winter of 2008 had the highest snow extent.
  16. Monckton Myth #7: Snowjob
    Albatross - you're correct, I confused this winter (which is only 33% complete, so Monckton's claim that there is "some chance" of a new record is rather silly) with last winter. I've corrected the text accordingly, thanks.
  17. A Case Study in Climate Science Integrity
    Lindzen is out to lunch if he thinks that this (see below) is not going to have an impact on the earth's energy budget. What you are seeing below is not a "fudge factor" as Lindzen would try and have you believe: [Sourced here] Santer recently called out Pat Michaels when he tried to use the same trick when testifying before Congress. I wonder what Lindzen and Michaels think about the new Glory mission? Why waste money then trying to learn more about the direct and indirect negative forcing of aerosols...
  18. Monckton Myth #7: Snowjob
    Once again the Viscount fails the truth test. His comment “…and there is some chance that a further record high will be set this year." should get some points on the “wishful thinking but so what?” test though. We should expect to see many short term snowfall records broken in the next half century. Unfortunately these kinds of cherries do grow in winter and they are and will continue to be a mainstay of the deniers’ diet. Thank you dana1981 for your continued effort.
  19. Monckton Myth #7: Snowjob
    Regarding the winter numbers, I don't have the reference, but I read a study that expected winter snow cover extent to trend downward over the course of the 21st century (I think contrarians disingenously pointed to this study as "disproving" predictions). While that hasn't happened in the first 10 years, it's way too short of a time period for any meaningful evaluation, especially with the AO trending downward since the 1990's. If global warming is leading to more weather configurations involving cold air being pushed far south and a mild Arctic, that would generally lead to greater snow cover extent in winter, and such would probably lead to revisions of earlier predictions. If in constrast, the recent trend is just a result of natural AO fluctations, it seems when AO trends positive, combined with the long-term global warming trend, winter snow cover extent will plummet. We'd see more values like 2007 and less.
  20. Monckton Myth #7: Snowjob
    Dana, Nicely done--Monckton and WUWT (curtosy Anthony Watts) sure are quite the prolific producers of misinformation and distortion. It seems that one could spend all day, every day refuting the spin and misinformation being highlighted at WUWT. Why then does Watts (and others) insist on claiming that WUWT is "...the world's most viewed climate website", when he knowingly allows Monckton to disseminate this nonsense? The Monckton/WUWT myths refuted here at SkS are the very antithesis of climate science. Having had my little rant, I did see something odd in your post though: "Prior to this winter, 2007-08 had the second-highest extent." Should that not read "third-highest"-- that is what the bar graph seems to be suggesting?
  21. A Case Study in Climate Science Integrity
    Following up to #17 and #21, Lindzen is basically trying to pass off a claim of a very low estimate of climate sensitivity as a best estimate, when in fact it's an entirely unrealistic and unsupported low estimate.
  22. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    This one uses another interface. http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/
  23. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    By the way, these are the official performances the weather prediction skill of various organisations. http://www.emc.ncep.noaa.gov/gmb/STATS/STATS.html
  24. A Flanner in the Works for Snow and Ice
    Gimme an A! Gimme a G! Gimme a W! What's that spell? AGW!!! AGW!!! AGW!!! Gooooooooo AGW!!! Yes, i am pro-AGW, it's my team, what can i say? I know it will make my life miserable, and ruin my children and maybe kill my grandchildren, but it's my side, and I am a loyal fan. I confess to morbid fascination with the declining Arctic sea ice. It's like watching a horrible wreck in slow motion, hard to believe it is happening, yet getting increasingly impossible to deny. But that other side doesn't give up! The Denialists! I hate their team! They can look at objective evidence and strongly Deny it all, first saying "It's not happening" and as the evidence that it is happening mounts, they cheer, "It's all natural!" and "It's a good thing!" I know my side will win though, and that makes me feel.... very very scared. (sorry to be sooo off topic and unscientific, fully understanding if this is deleted by the moderator)
  25. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    Rhetorically challenged? Try: Weather is local and brief; Climate is global and long lasting. Weather is the part; Climate is the whole thing. Weather is detailed and can be predicted accurately, within a week, 90% of the time. Climate is broad and basic and can be predicted adequately decades ahead. Climatologists may not be able to tell you the exact temperature or whether it rained or not in your neighborhood on June 1st 10,000 B.C.; but they can tell you if the general conditions where wet or dry; hot or cold.
  26. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    As we say where I live, if you don't like the weather just wait 15 minutes, it will change. A 12F change in a day is not newsworthy, other than the few minutes spent on the weather forecast on the nightly news.
  27. The Climate Show #5: Green roofs and Brisbane floods
    Camburn @16, "One thing I have noted is the seemingly absense of error bars in the papers. It is very hard to draw conclusions without those present." That is a generalized statement, and I can only assume it applies to the Allan et al. (2010) paper. If so, you then need to look at the data in their Table 1 (you can view the PDF by clicking on the PDF hyperlink below the abstract) which does in fact include 95% confidence intervals (i.e., error bars) for the satellite data, GPCP data and modelling data. Regardless, Zhang et al. (2007) used observed gauge data: "We used monthly precipitation observations over global land areas from the most recent version of the Global Historical Climatology Network (GHCN) to analyse precipitation trends in two twentieth century periods". "Our best estimate of the response to anthropogenic forcing suggests (Fig. 1b) that anthropogenic forcing has contributed approximately 50–85% (5–95% uncertainty) of the observed 1925–1999 trend in annual total land precipitation between 40 N and 70 N(62 mm per century), 20–40% of the observed drying trend in the northern subtropics and tropics (0 to 30 N; a decrease of 98 mm per century) and most (75–120%) of the moistening trend in the southern tropics and subtropics (0 to 30 S; 8 mm per century)." Note the ranges (i.e., uncertainty ranges). And note the impact on the S. Hemisphere tropics and subtropics have been affected. Camburn, you seem to be seeking out excuses to convince yourself that AGW is not happening and/or that the consequences in many cases are not going to be unpleasant. Feel free to seek out excuses, you are after all entitled you your opinion and interpretation of the facts, but you are not entitled to your own facts. The fact that we can already discern a notable impact on the hydrological cycle from the warming is very telling and not at all reassuring. Consider this paper by Lenderink and Meijgaard (2008, Nature): "Here, we analyse a 99-year record of hourly precipitation observations from De Bilt, the Netherlands, and find that one-hour precipitation extremes increase twice as fast with rising temperatures as expected from the Clausius–Clapeyron relation when daily mean temperatures exceed 12 °C" Only one location, but the physics apply to your part of the world too.
  28. thepoodlebites at 05:17 AM on 25 January 2011
    It's Pacific Decadal Oscillation
    #67 Let's say (for the sake of argument) that the Jan. 2011 UAH anomaly is -0.2 C, a good possibility. The Dec. 2010 UAH anomaly was +0.18 C, a fact that is not in dispute, I hope. From the plot we can see that the monthly anomaly would then be back down to near Jan. 2008 (-0.3 C). Actually, that would bring us all the way back to near the beginning of the satellite record, June 1979 (-0.2 C). And remember, the peaks in 1998 and 2010 were from El Nino warming. The latest SST's still show La Nina. These are monthly means, whether the 12-month running mean drops to near zero will be determined in the coming months. Continued warming would mean higher highs and higher lows. Yeah, I'd say it's a wipe-out, just like in 2008.
  29. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    #15 notcynical "Wow, 7C is 12.8F; 80F vs 92.6F, 20F vs 32.6F are not worth noting?" I you call a notation on a web page stating that there is an abnormal temperature trend as being noteworthy. Take London Canada for instance. The overnight temperatures are expected to rise by 19.8oC (35.64oF) in a 24 hour period. You won't find any hoopla in the media about it though. It's just simple weather variability. A cold front moved into the region and now it's being pushed out. Big deal. Now if the temperature were to change from -22.8oC to 22.80C in a 24 hour period, then it might be noteworthy.
  30. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    Dikran@24 I meant scale as perceived by a human. eg. A person only experiences a weather event at a very localised level and that can seem highly erratic. One can be walking along and one minute you are in a shower, the next you aren't. This localisation and detail is impossible to predict, but at the greater scale (say) from space, the weather event may seem more uniform and conforming to obvious turbulent behaviour. It's like picking up a lump of wood, it has some obvious characteristics that are well known and common to all lumps of wood, but go down to the atomic scale and things are a lot different. Molecules are moving and vibrating and it would be difficult to equate what was happening in molecule land with the formation of tree rings etc. In the analogy, a typical Joe or Jane is living with the atoms, not seeing the bigger picture. They are just interested in buying a reliable car and knowing what the weather will be like in the afternoon. Probably should have explained in more detail. My comment was really to do with peoples perceptions. The vast majority of people think on a basic level on a daily basis. I happily watch science on TV. But the vast majority would prefer to watch a soap, or reality TV. If you start talking about science, you just get a blank face or a frown!
  31. Marvin Gardens at 04:27 AM on 25 January 2011
    Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    Great analogy about the pool and the hose and the waves. Couldn't we just as easily say the input from the hose was increased radiation from solar activity? More record highs than lows provides an increasing average which is exactly what one would expect from a warming climate.
  32. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    LandyJim @9, "Many climate models are presnted to the public as fact, in 50 years the planet WILL be 7°C warmer, the ice-caps WILL have melted and the ocean WILL be 7m deeper." I'm afraid that this statement is false, at least how it pertains to the science and the IPCC and the governments which signed off on the IPCC reports. Please note the following statement from the IPCC: "An expert assessment based on the combination of available constraints from observations (assessed in Chapter 9) and the strength of known feedbacks simulated in the models used to produce the climate change projections in this chapter indicates that the equilibrium global mean SAT warming for a doubling of atmospheric carbon dioxide (CO2), or ‘equilibrium climate sensitivity’, is likely to lie in the range 2°C to 4.5°C, with a most likely value of about 3°C. Equilibrium climate sensitivity is very likely larger than 1.5°C. For fundamental physical reasons, as well as data limitations, values substantially higher than 4.5°C still cannot be excluded, but agreement with observations and proxy data is generally worse for those high values than for values in the 2°C to 4.5°C range. The ‘transient climate response’ (TCR, defined as the globally averaged SAT change at the time of CO2 doubling in the 1% yr–1 transient CO2 increase experiment) is better constrained than equilibrium climate sensitivity. The TCR is very likely larger than 1°C and very unlikely greater than 3°C based on climate models, in agreement with constraints from the observed surface warming." [IPCC AR4 WGI page 749] Now compare that with what WUWT says, just one example but there are many more: "New paper from Lindzen demonstrates low climate sensitivity with observational data" [here] Anyhow, we are getting way off topic here...
  33. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    An excellent analogy John. I will be sure to use that in the future. Sure beats me trying to explain to people that weather is an initial value/conditions "problem", while predicting climate is a boundary forcing "problem". But as you note it is a red herring and an appeal to emotion. Yet another trick employed by "skeptics" and contrarians. The sad truth is that many weather agencies do not provide the public verification statistics, or make them easily available. So the misconception has been that forecasts are not good-- using anecdotal evidence to validate forecasts is absolutely awful. The UK Met office does an excellent job of communicating their verification stats to the public.
  34. Oceans are cooling
    HumanityRules, #54: To get anything quantitative, one would have to specify: - the magnitude of the driving temperature variation at each frequency - take into account the very complicated mixing of layers (one thing I can see from the graphs is that different things are happening at different latitudes; that means that water at different layers are mixing) - take into account the initial conditions. In the end, the best thing to do is to model the system numerically: including both the heat flow and the very complicated water flow. All I'm using this set of frequency-specific analytical solutions for is to understand a few qualitative features: i.e., why the long-period oscillation has more "thermal inertia" than the short-period oscillations. It helps the intuition a bit, but isn't good for making very detailed comparisons.
  35. Dikran Marsupial at 03:55 AM on 25 January 2011
    Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    The Ville Actually scale isn't nearly as much of a problem as you might think. In a Taylor series expansion, the more terms you add, the more accurate the approximation to reality, even though to get a completely accurate model you often need an infinite series. But that doesn't mean that even very crude Taylor series expansions with only a couple of terms don't provide a useful approximation. Similarly for GCMs, the higher the spatial and temporal resolution (the more "scale" you include), you become able to make more detailed projections on finer spatial and temporal scales. It isn't a matter of you can model climate or you can't, it is a matter of how accurate and how refined the projections you can make. Using current technology, GCMs work well at global and regional scales (e.g. continents), but don't have the resolution to make useful projections on sub-regional or national scales. So the "scale problem" is not a problem as long as the appropriate caveats are placed on the projections (and scientists being scientists, the papers are generally full of such caveats). As GEP Box (famous statistician - if that isn't a contradiction) said "all models are wrong - but some are useful".
  36. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    Please note the unnecessary apostrophe in the title of this post.
  37. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    I used to use a gambling analogy to explain this to people: you can't predict the result of an individual pull on a slot machine, but you know the results will conform with the house odds over the longer term. Unfortunately, I've found that most of the people who find this "skeptical" argument compelling also don't quite get the concept of house odds. They're more likely to think about outcomes in terms of fate. Which is not all that different from "skeptics," really; they're both very bad gamblers, IMO, with a strong faith in last-minute miracles and a strong tendency to downplay their losses.
  38. Monckton Myth #6: Global Sea Ice
    GC: The Copenhaen Diagnosis is not produced by the IPCC. If you want to slander someone in the future please refer to the correct people. The jury is still out on whether the Arctic ice is collapsing or not. The ice volume continues to rapidly decline. Estimates of when the Arctic will be ice free have gone from 2050-2100 in the IPCC report (written in 2007) to 2014-2040 now, only three years later. I would call ice free by 2020 "a dramatic decrease in Arctic ice" that was foreseen in 2007. It is obvious from the data that the IPCC was much too conservative!! Why aren't you complaining about that? We can compare notes again in September to see how the melt goes this year. Cite a scientist who claimed that the Arctic would be ice free before 2015. Find a consensus report that gives a date before 2020. Stop making wild strawman arguments about NSIDC and IPCC being alarmist. Deniers always make these type of wild argument so they can knock down the strawman.
  39. A Flanner in the Works for Snow and Ice calculations
    Well, by definition the calculations are for an equilibrium sensitivity (this is true and physical), but what we don't know is whether the value of the feedback parameter we measure now will be the same by the time we reach equilibrium. Which is what your second paragraph is saying! I worded my post saying that if the current measurements are representative of what we ultimately get then this means a big boost to climate sensitivity. But I also tried to make it clear that perhaps it's a case of things just melting more quickly than we expected to begin with and maybe albedo feedback will 'slow down' and head back to model values. All the paper shows is that models underestimate what we expect to see so far, we can probably be confident about that (but ofc we need to see further work for confirmation!) - but more work is needed to have greater confidence that we've underestimated the long term feedback.
  40. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    @15 "" Wow, 7C is 12.8F; 80F vs 92.6F, 20F vs 32.6F are not worth noting? The whole post lost some credibility with that statement." You are making an argument without substance. I just pulled the daily average records for Nephi, Utah (station 426135 in the Historical Climatology Network - a fairly random pick), wrote a small script to compute the absolute difference between successive days (excluding dates with missing data) and of the 23972 date pairs, 1302 of them had *at least* 12F difference. That is an average of about 1.6 times per month. Even limiting it to 13F, we get 938 instances for an average of a bit over 1.1 times/month. Something that happens, on average, more than once a month is not unusual enough to warrant special note. As for the 'One question is why has the pool level not gone up much, if at all, in the last 10 years' comment, that belongs over in the Did global warming stop in 1998? thread.
  41. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    Further where did you happen to get that models are predicting this in the first place Jim?
  42. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    #9 LandyJim "in 50 years the planet WILL be 7°C warmer, the ice-caps WILL have melted and the ocean WILL be 7m deeper." Oh come now. I myself might believe that abrupt climate change might be something that we face, but I don't make rash statements like this. Unless you can substantiate this claim, it amounts nothing less than "scaremongering".
  43. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    Good point, Notcynical. As a high school student, we were shone An Inconvenient Truth by several well-meaning teachers. The result was polarizing to say the least. The movie was alarmist and non-scientific. Are there any charts available which plot the rise and fall of other greenhouse gases?
    Moderator Response: You are incorrect. See "Al Gore got it wrong." Regarding other GHGes, see "CO2 only causes 35% of global warming," "It’s CFCs," "It’s ozone," "CO2 is not the only driver of climate," "Water vapor is the most powerful greenhouse gas," "Humidity is falling," and "It’s methane."
  44. Pete Dunkelberg at 01:45 AM on 25 January 2011
    A Flanner in the Works for Snow and Ice calculations
    Thanks Mark. I see that you have a good point. However it is a bit brash to say that certain symbols "by definition" represent an actual physical quantity. Consider this possible physical process: spring now comes earlier snow melts and becomes water wet ground reflects less light than dry ground (I presume here) A century later, spring comes much earlier. Then, by the time each spring when the ground is now wet with melt water, it has dried. Albedo goes back to dry ground albedo. (The wet ground period comes earlier when the sun is a lower angle). Result: equilibrium sensitivity is lower than what you project here.
  45. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    I've met this one. It can actually be addressed without getting into chaos theory by looking at the structure of the formal argument... 1. Weather in unpredicatable (beyond x days...) 2. Given that weather is unpredictable, it necessarily follows that climate is unpredictable. What is climate? Roughly, the statistics of weather. Thus: 1. Weather in unpredicatable (beyond x days...) 2. Given that weather is unpredictable, it necessarily follows that the statistics of weather are unpredictable. The argument falls if either premise is incorrect. The second premise takes the form: "Given that X is unpredictable, it necessarily follows that the statistics of X are unpredictable." Which can be falsified by example: Given that dice are unpredictable, it necessarily follows that the statistics of dice are unpredictable. Given that lottery machines are unpredictable, it necessarily follows that the statistics of lottery machines are unpredictable. Given that crimes are unpredictable, it necessarily follows that the statistics of crime are unpredictable. Given that hard disk failures are unpredictable, it necessarily follows that the statistics of hard disk failures are unpredictable.
  46. A Flanner in the Works for Snow and Ice
    There's that term again -- "pro-AGW." What a weird thing to label people who would probably give their right and left arms to keep the climate as stable as it has been for the last several thousand years.
  47. A Quick and Dirty Analysis of GHCN Surface Temperature Data
    I'm afraid I think I found a mistake. I was trying to reproduce your result in python and failing. Eventually I had to instrument your code and mine, and eventually I found out the mistake. You use characters 3-7 of the station id as a key, I use 0-10. The documentation isn't very clear, but here's what I get from it and from various blogs: - The first 3 characters a country code, irrelevent for our case because it can be deduced from the rest of the station ID. So omitting this is fine. - The next 5 chars are the WMO station code. - The final 3 are the imod code. IIUC this is used for stations which so not have a WMO code. The station is given the code of the nearest WMO station, which may be a substantial distance away, plus a non-zero imod code to distinguish it. The problem is that the imod!=0 stations are separate stations. By ignoring the imod code, you merge all of these stations into the single WMO station. In the case of disjoint records, the resulting record contains both (but only gets a single baseline), in the case of overlapping records, the last overwrites the others. Examples include: 68262: 14168262000 14168262001 44373: 21544373000 21544373002 72211: 42572211001 42572211002 42572211003 72214: 42572214000 42572214001 72217: 42572217001 42572217002 42572217004 72672: 42572672000 42572672001 42572672002 42572672003 72671: 42572671001 42572671002 42572671003 42572671004 42572671005 42572671006 72670: 42572670001 42572670003 42572670004 42572670005 42572670006 42572670007 42572670008 42572670009 42572670010 42572670011 42572670012 So I changed this in my program and verified I could reproduce your results. Here's my 2 graphs plus yours: http://postimage.org/image/35hd6ufc4/ Note that with 5/8 char station IDs I match your results pretty well. With 11 char IDs the results are rather different. What threw me for a while is that the full ID gives apparently worse results, so I assumed at first that it was my mistake. In particular, it shows a much larger hump around 1935. But looking at the station IDs, it is clear that a lot of the imod codes are in the US (country=425). I think what your code is doing is merging a lot of US stations, and thus reducing the overweighting of US data arising from the over-representation of US stations in the data. The correct solution of course is geographical binning (or some equivalent method) to deal with this over-representation. So I implemented that in my version. Here's what I get, along with NASA's resutls: http://postimage.org/image/2f5tftz9g/ Note that the difference between the 5 and 11 char versions is now reduced, and apart from the sparse early data the curves follow the gistemp data quite well, including the 1935 period. I'm still not 100% certain, so I'm hoping someone more knowledgeable will comment, but at the moment it seems to me that the 11 character approach is the correct one.
  48. Pete Dunkelberg at 01:24 AM on 25 January 2011
    A Flanner in the Works for Snow and Ice
    Here is a pdf file of the slides from a presentation of the paper. MarkR, I appreciate your comments. Since you mention textbooks, why not name and briefly describe a couple?
  49. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    "A change in temperature of 7º Celsius from one day to the next is barely worth noting when you are discussing weather." Wow, 7C is 12.8F; 80F vs 92.6F, 20F vs 32.6F are not worth noting? The whole post lost some credibility with that statement. The pool analogy is a good one... up to a point. One question is why has the pool level not gone up much, if at all, in the last 10 years even though the water has been flowing in at an ever increasing rate. This is not to deny that water is flowing into the pool, just that things are not so simple, and that there are still some things we do not have a good explanation for.
  50. Eric (skeptic) at 01:00 AM on 25 January 2011
    Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    The example of 7 degrees change in average should perhaps be supplemented with a sentence on the length of time versus the type of prediction. The GAT just dropped 0.1 degrees in two days which could not have been predicted a week ago. Last year a rise of 0.3 degrees in a month was only as predictable as the El Nino with a few months skill at best. At the same time that we are inflicted with unpredictable day-to-day changes in albedo, week-to-week changes in atmospheric circulation, month-to-month in ocean circulation, the GAT plods upward decade-to-decade reflecting AGW and (to various debatable extents, long term cycles). Prediction of AGW is deterministic and can be greatly helped with empirical studies (e.g. measurements of actual OLR changes from feedback processes). The greatest uncertaintly in AGW predictions is the changes in weather itself, e.g., will AO become more positive or more negative (or cycle between both extremes or neither)? Temperature data source http://discover.itsc.uah.edu/amsutemps/data/amsu_daily_85N85S_ch05.r002.txt

Prev  1941  1942  1943  1944  1945  1946  1947  1948  1949  1950  1951  1952  1953  1954  1955  1956  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us