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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 112951 to 113000:

  1. Antarctica is gaining ice
    Thanks for pointing this out over at CP. There, I made the assumption that "sea ice" meant floating icebergs. My bad.
  2. Models are unreliable
    There is a trade off betweeen concern for the most vulnerable and mistrust of governments. I am not a confirmed beleiver in the network of socialists doctoring results for their trotskyite masters. That said inevitably there will be incidences where the responsability of stewardship weighs heavy on scientific rigour. The code should be available so we can move on. We all agree models will be better in the future. Not to heed what they are currently delivering is an imprudency beyond recall.
  3. On Statistical Significance and Confidence
    Good post, Alden. Communicating anything to the public does indeed require a minimal usage of jargon; but as we all know, there exist those who live to be contrarians, for whom no level of clear explanations exist that cannot be obfuscated. Thanks again! The Yooper
  4. Stephan Lewandowsky at 09:31 AM on 11 August 2010
    On Statistical Significance and Confidence
    I would appreciate some more background on how you computed the Bayesian credible interval. For example, what exactly do you mean my non-informative prior? Uniform? And how did you deal with auto-correlations if at all? (I realize that I am asking for the complexity you seek to simplify--fair enough, but a 'technical appendix' might be helpful for those more conversant with statistics.)
  5. Models are unreliable
    Pete Ridley at 07:12 AM on 11 August, 2010 I'm guessing you read the comments and not the details of the paper? The paper itself is interesting, as M,M&H confirm that tropical Lower Troposhere temperature trends from 1979 to end of 2009 are significantly positive, and to an extent reflect the earlier views in Santer 2008. See my comment on tropospheric hot-spot for some background on this. At the time of writing that comment I suggested that the inclusion of the 2010 data would allow the trends to more closely approach statistical “robustness”, so confirmation is a useful step. They also confirm the known issues with the earlier models used by Santer, and also confirm that the differences between the UAH and RSS MSU datasets are now statistically significant. For the Tropical Lower Troposphere temperature data they quote “In this case the 1979-2009 interval is a 31-year span during which the upward trend in surface data strongly suggests a climate-scale warming process”. That the original model was flawed in this case is old news, and this has been discussed here previously. I note once again some of your sources (and the comments on this new paper) lack context and scientific objectivity.
  6. Berényi Péter at 08:54 AM on 11 August 2010
    Temp record is unreliable
    #105 Peter Hogarth at 07:58 AM on 11 August, 2010 Bekryaev lists all sources (some of them available for the first time), the majority with links, though I admit I haven't followed them all through. Show us the links, please. I am surprised you make comments without even looking at the paper. Anyway, I genuinely thought you might be interested. I am. However, I would prefer not to pay $60 just to have a peek what they've done. I am used to the free software development cycle where everything happens in plain public view. #104 Ned at 07:11 AM on 11 August, 2010 Obviously, stations in northern Canada are mostly warming faster than those further south I see that. However, that does not explain the fact the bulk of divergence between the three datasets occurred in just a few years around 1997 while the sharp drop in Canadian GHCN station number happened in July, 1990. Anyway, I have all the station coordinates as well, so a regional analysis (with clusters of stations less than 1200 km apart) can be done as well. But I am afraid we have to wait for that as I have some deadlines, then holidays as well.
  7. More evidence than you can shake a hockey stick at
    Does anyone know the cause of the dip in CO2 concentrations on the slide featured in post 15, the dip being about 1500 AD.
  8. Greenland's ice mass loss has spread to the northwest
    Fascinating article about Greenland here in the UK's Daily Mail. A reporter visits scientists working this summer on the ice sheet, investigating drainage. Some great photos.
  9. Models are unreliable
    Pete, worth noting also that you won't find a refutation to M&M 2010 coming from here, you'll find it reported if and when such a refutation appears. The sites you mention are in full celebration but of course they're not adding any information of their own, the actual information is all in the paper itself. Hopefully for M&M the air the party won't be over before their work actually appears in print. :-)
  10. Temp record is unreliable
    Berényi Péter at 07:07 AM on 11 August, 2010 Thanks for fixing the links, though I think Ned has actually answered one question I had quite efficiently. I'm not sure what it is I still don't get? (why so defensive?) Bekryaev lists all sources (some of them available for the first time), the majority with links, though I admit I haven't followed them all through. I am surprised you make comments without even looking at the paper. Anyway, I genuinely thought you might be interested.
  11. Models are unreliable
    I might add as a gratuitous fling, the amount of back-slapping and rejoicing around M&M's first accepted comment in years is indicative of the general poverty of their camp. Looking at the comment threads erupting around this I'm reminded of meat being thrown into a kennel full of emaciated dogs. Folks outside the kennel have more to eat than they care to look at, frankly, are amply fed with dismal facts. Less gratuitously, this publication immediately moves me to point out that not everybody can feed from the meal on offer. Those who've committed themselves to trying to show the temperature observations under discussion are meaningless will have to go hungry unless they disagree w/M&M. Those saying there's no trend will also have to continue listening to their stomachs rumbling, because again M&M's results depend on observing a trend.
  12. Confidence in climate forecasts
    For some reason my earlier post of this comment was removed so I’ve modified it slightly. I can’t see any violation of the comments policy.
    Moderator Response: Putting duplicate comments into multiple threads leads to incoherent discussion.
  13. Models are unreliable
    James Annan comments on M&M's comment as published in ASL: A commenter pointed me towards this which has apparently been accepted for publication in ASL. It's the same sorry old tale of someone comparing an ensemble of models to data, but doing so by checking whether the observations match the ensemble mean. Well, duh. Of course the obs don't match the ensemble mean. Even the models don't match the ensemble mean - and this difference will frequently be statistically significant (depending on how much data you use). Is anyone seriously going to argue on the basis of this that the models don't predict their own behaviour? If not, why on Earth should it be considered a meaningful test of how well the models simulate reality? Of course the IPCC Experts did effectively endorse this type of analysis in their recent "expert guidance" note, where they remark (entirely uncritically) that statistical methods may assume that "each ensemble member is sampled from a distribution centered around the truth". But it's utterly bogus nevertheless, as there is no plausible situation in which that can occur, for any ensemble prediction system, ever. Having said that, IMO a correct comparison of the models with these obs does show the consistency to be somewhat tenuous, as we demonstrated in that (in)famous Heartland presentation. It is quite possible that they will diverge more conclusively in the future. Or they may not. They haven't yet. Annan Should be quite a stir out of this, papers of this sort being few and far between. Worth noting that Annan is an unflinching critic of whatever he sees wrong w/IPCC, etc. Probably a useful snapshot metric of the significance of M&M's output here.
  14. Models are unreliable
    Jo Nova’s blog has an interesting new article “The models are wrong (but only by 400%) ” (Note 1) which you should have a look at, along with the comments. It covers the recent paper “Panel and Multivariate Methods for Tests of Trend Equivalence in Climate Data Series” (Note 2) co-authored by those well-known and respected expert statisticians, McIntyre and McKitrick, along with Chad Herman. David Stockwell sums up the importance of this new paper with “This represents a basic validation test of climate models over a 30 year period, a validation test which SHOULD be fundamental to any belief in the models, and their usefulness for projections of global warming in the future”. David provides a more detailed comment on his Niche Modeling blog “How Bad are Climate Models? Temperature” thread (Note 3) in which he concludes “But you can rest assured. The models, in important ways that were once claimed to be proof of “… a discernible human influence on global climate”, are now shown to be FUBAR. Wouldn’t it have been better if they had just done the validation tests and rejected the models before trying to rule the world with them?”. Come on you model worshipers, let’s have your refutation of the McIntyre et al. paper. NOTES: 1) see http://joannenova.com.au/2010/08/the-models-are-wrong-but-only-by-400/#more-9813 2) see http://rossmckitrick.weebly.com/uploads/4/8/0/8/4808045/mmh_asl2010.pdf 3) see http://landshape.org/enm/how-bad-are-climate-models/ Best regards, Pete Ridley
  15. Temp record is unreliable
    That map from my previous comment also nicely illustrates the conceptual flaw in the claim (by Anthony Watts, Joe D'Aleo, etc.) that the observed warming trend is an artifact of a decline in numbers of high-latitude stations. Obviously, stations in northern Canada are mostly warming faster than those further south. So, if you did use a non-spatial averaging method, dropping high-latitude stations would create an artificial cooling trend, not warming. Using gridding or another spatial method, the decline in station numbers is pretty much irrelevant (though more stations is of course preferable to fewer).
  16. Berényi Péter at 07:07 AM on 11 August 2010
    Temp record is unreliable
    #101 Peter Hogarth at 04:25 AM on 11 August, 2010 some of the links seems to be broken? Yes, two of them, sorry.
    • GHCN data
    • March, 1840 file at Environment Canada - this one only contains a single record for Toronto, but shows the general form of the link and structure of records
    Anyway, does your first chart represent published results or just your own analysis? As I have said, it is my own analysis. But it is a pretty straightforward one using only public datasets. Really nothing fancy, anyone can repeat it. BTW, the result, as you can see, is published (here :) It is not peer reviewed of course. But since the quality of the peer review process itself is questioned in this field, it is a strength, not a deficiency. Any review is welcome. have a look at Bekryaev 2010 which uses data from 441 high latitude and Arctic surface stations You still don't get it. The Bekryaev paper is useless in this context, as it is neither freely available nor has its supporting dataset published. Therefore it is impossible to repeat their analysis or check the quality of their data here and now. Credibility issues can get burdensome indeed.
  17. Temp record is unreliable
    Berényi Péter writes: Unfortunately I do not have too much time for this job, you may have to wait a bit. Like Berényi Péter, I also don't have a lot of time right now, being about to leave for vacation in a few days and having far too much to do. But I thought it would be worth putting up a quick example to illustrate the necessity of using some kind of spatial weighting when analyzing spatially heterogeneous temperature data. Since BP uses Canada as his example, I'll do the same. He mentions a useful data source, the National Climate Data and Information Archive of Environment Canada. I'll use the same data source. Since I want to get this out quickly, I'm just using monthly mean temperature data from July, and as another shortcut I'll just look at every 5 years (i.e., 2010, 2005, 2000, 1995, ...) I picked July because it's the most recent complete month and 5-year intervals for no particular reason. Maybe sometime later I can expand this to look at the complete monthly data set. In any case, using just one month per 5 year interval will make this analysis more "noisy" than it would otherwise be, but that's OK. I then identified all stations with data in all years, and whose name and geographic coordinates were exactly the same in all years. There's just over 150 of them: Note, first, that the stations aren't distributed uniformly. Note, second, that the trends differ greatly in different regions. In particular, note that there are a large number of stations showing cooling in inland southwestern Canada. There are also a lot of stations showing warming across eastern and northern Canada. (This is an Albers conical equal-area projection, so the apparent density of stations is proportional to their actual density on the landscape). If you calculate the trend for each station, and then just take the overall non-spatial average, you get a slight cooling of about -0.05C/decade for Julys in the 1975-2010 period. But as the map shows, that's quite unrealistic as an estimate of the trend for the country as a whole! The large number of tightly-clustered stations in certain areas outweighs the smaller number of stations that cover much larger areas elsewhere. To estimate the spatially structured temperature trend I used a fairly simple kriging method. This models a continuous surface based on the irregularly distributed station data. There are many other approaches that could be used (e.g., gridding, other interpolation methods, etc). Anyway, the spatially weighted trend across all of Canada is warming of +0.18C/decade. So ... a naive nonspatial analysis of these data give an erroneous "cooling" of -0.05C/decade. A spatially weighted analysis gives a warming of +0.18C/decade. This is why I keep telling Berényi Péter that his repeated attempts to analyze temperature data using simple, nonspatial averages are more or less worthless. Again, this is based on a small fraction of the overall data set, and a not necessarily optimal methodology. But it's sufficient to show that using real-world data you can end up with seriously misleading results if you don't consider the spatial distribution of your data.
  18. Why I care about climate change
    Doug, You have made my day. Knowledge of the existence of such a thing as 'conservapedia' enriches my existence. I suggest to anyone not willing to believe in relativity that they immediately forfeit their GPS units. Given these remarks about quantum mechanics, "Collapsing of the wave function is by no means magic. In can be intuitively understood as this: You find a particle at a particular spot; if you look again immediately, it's still in the same spot, they should also forfeit all semiconductor-based electronics. Of course, they have wonderful things to say about global warming: "The anthropogenic global warming theory is one of several explanations for the 1.5 degrees F of warming of the earth's surface recorded since the middle of the 19th century. The theory enjoys broad based political support from Liberals, Greens and the US Democratic Party, and theory supporters frequently assert the existence of a "scientific consensus" favoring their viewpoint" Not too long ago (during the height of the ID debate in the US), this was a popular cartoon in the world of science education:
  19. Grappling With Change: London and the River Thames
    doug_bostrom at 04:22 AM on 11 August, 2010 Agreed.
  20. Grappling With Change: London and the River Thames
    Pete if you don't mind I'll refer to something you said in relation to Ned's recent post, as support for a general observation. Pete said: I may be able to make time for a further read but looking at some of the over 200 references mentioned there to “uncertainties” and “estimates” about those horrendously complex global climate processes and drivers gives me a hint that I’ll be wasting valuable time. I was disappointed to see virtually nothing about assumptions made. Looking beyond the immediate topic of sea level rise, Ned's remark exactly illustrates how Pete's reasoning about "wasting time" looking at citations is incorrect, and how his remark about seeing "virtually nothing about assumptions made" is not actually right. We have to look at all the information made available to us if we want to avoid ambiguities leading to fallacious conclusions. If we choose not to or cannot find the time to do so, that's not an argument against the worth of what we personally don't know. Personalizing this, for the article above I made a best effort to summarize what I was able to find from a variety of authoritative sources on London and floods. If I missed something in my research leading to errors in my little essay, that doesn't mean I'm right and the rest of the world is wrong, it simply means I'm ignorant of certain things. Ignorance is universal and thus permissible but we should deal with ignorance in a conservative way; I should not claim that because I don't know something nobody else does, or that my perspective is correct when I have cause to believe I don't have a complete grasp of my topic. I should be mindful of accidentally conveying and promoting misperceptions springing from my ignorance.
  21. Temp record is unreliable
    Berényi Péter at 23:54 PM on 10 August, 2010 Peter, some of the links seems to be broken? Anyway, does your first chart represent published results or just your own analysis? If you are interested in Arctic surface station records have a look at Bekryaev 2010 which uses data from 441 high latitude and Arctic surface stations.
  22. Grappling With Change: London and the River Thames
    Not to prematurely consign my article to the dustbin of history but the topic of accuracy of sea level measurements is already treated here on SkS and includes some helpful discussion around confusion concerning sea level measurement and the like. Rather than reenacting that history here, perhaps it would be better to contribute to existing threads. "How much is sea level rising" has a well developed discussion on measurement uncertainties. There's also "How much will sea levels rise in the 21st Century?", devoid of discussion but with a writeup by John Cook including data to work from, probably more germane to the exact discussion that has arisen here.
    Moderator Response: Excellent suggestion. This is one of those cases in which an original post on a broad topic legitimizes comments on all those topics, but at some point the comments get so detailed that continuation on that original thread no longer is appropriate. Everyone is welcome to post a comment on this thread, announcing that they have posted a comment on a more specialized, relevant thread. I suggest you even paste a link to your comment on that other thread. (Right click on the time-date stamp of your comment on the other thread.)
  23. Grappling With Change: London and the River Thames
    Let's see. In these two comments (first, second) Pete Ridley suggests that we should use data from a network of 12 GPS stations in the South Pacific to look at sea level rise. He also dismisses global studies of sea level based on the combination of satellite altimetry and gauge data. The satellite record shows a global trend of around +3.3 mm/year over the past two decades (thanks, Peter Hogarth!) The South Pacific GPS network that Pete Ridley refers to shows individual trends ranging from +3.2 to +8.6 mm/year (ignoring one outlier of +16.8 mm/year). The mean is +5.4 mm/year and the median is +4.9 mm/year. So, the network of stations that Pete Ridley was recommending actually shows a rate of rise that's about 50% greater than the global mean from the satellite record. However, as noted in the annual reports on the South Pacific GPS project, sea level in that region is known to be rising faster than the global average, and this regional difference shows up in the altimetry data as well. Taking this regional difference into account, their annual reports conclude that: The net sea level trends are positive at all sites, which indicates sea level in the region has risen over the duration of the project. The sea level rise is not geographically uniform but varies spatially in broad agreement with observations taken by satellite altimeters over a similar timeframe. [...] The sea level trends from SEAFRAME stations are mostly higher than the global average rate, but this is consistent with higher rates in the southwest Pacific measured by satellite altimeters So, if Pete Ridley likes the South Pacific CGPS project, he must also approve of the global satellite-based sea level record, since the two data sets are mutually consistent. Surely Mr Ridley isn't arguing that the satellite altimeters are accurate over the South Pacific but inaccurate over the rest of the ocean.....
  24. Why I care about climate change
    Further to muoncounter's remarks, one of my concerns about this brouhaha over climate science is how the tactics employed to degrade public confidence in climate research necessarily can't and don't respect borders of inquiry. If somebody becomes the victim of purposeful confusion about the difference between hypothesis and theory or what "uncertainty" means in terms of confidence in scientific findings they're going to carry that loss of coherence everywhere they go, see everything through the same fuzzy cloud. Leading to things like this: The equations for special relativity assume that it is forever impossible to attain a velocity faster than the speed of light and that all inertial frames of reference are equivalent, hypotheses that can never be fully tested. Relativity rejects Newton's action at a distance, which is basic to Newtonian gravity and quantum mechanics. The mathematics of relativity assume no exceptions, yet in the time period immediately following the origin of the universe the relativity equations could not possibly have been valid. ... Relativity has been met with much resistance in the scientific world. To date, a Nobel Prize has never been awarded for relativity. Louis Essen, the man credited with determining the speed of light, wrote many fiery papers against it such as The Special Theory of Relativity: A Critical Analysis.[6] Relativity also gravely conflicts with quantum mechanics, and although theories like string theory and quantum field theory have attempted to unify relativity and quantum mechanics, neither has been entirely successful or proven. ... Despite censorship of dissent about relativity, evidence contrary to the theory is discussed outside of liberal universities. ... The Theory of Relativity enjoys a disproportionate share of federal funding of physics research today. Conservapedia article "Theory of Relativity" Sound familiar?
  25. Remember, we’re only human
    Typo alert: I meant to say "The Isles of Britain can't and don't support their population."
  26. Remember, we’re only human
    Humanity Rules: "Yep Malthus was wrong. He believed the Isles of Britain could not support more than 7 million people. He was wrong." The Isles of Britain can't and don't support more than 7 million people. The resources that actually support its population come from all over the globe, just like the resources that support other first-world countries. The population of Tokyo, for instance, is "supported" by a land area that's roughly three times greater than the land area of Japan. This situation is extremely vulnerable to various types of climactic disruption, wholly apart from the fact that we're running an unsustainable ecological deficit. Hope is not a plan, as the saying is.
  27. Grappling With Change: London and the River Thames
    Pete Ridley at 00:26 AM on 11 August, 2010 All of the recent global sea level analyses use similar high resolution tide gauge data, as well as GPS/satellite altimetry as in the South Pacific Project. There is a global integrated sea level monitoring system and the South Pacific stations are part of it. In my view you have been extremely selective in your choice of references on sea level. Have a look at this short article on sea level rise where I cite the main recent references available in early 2010, and incidentally provide some visual clues as to why sea level rise in the South Pacific is not representative of sea level rise globally, notwithstanding that a 15 year period is less likely to give statistically significant trends when analysing individual stations (this seems to be a tactic often used by skeptics) as has been done in your reference. I could cite you many individual tide stations where sea level has actually fallen over the entire satellite recording period, but this does not change the global result. I suggest you gain much more knowledge of climate data and recent scientific research, and then balance this against the minority views of Spencer.
  28. Grappling With Change: London and the River Thames
    Pete, The study you referenced in 63 was not a scientific evaluation of the data the Australian gorvenment collected. It was a denier eyeballing the data and concluding the Australians were wrong when they measured the sea level rising. I have no problem with the Australain data. Why don't you use the scientists evaluation of their own data here instead of some denier pap? If you have a problem with the NAS data you need to read their references. In a summary report they do not have enough space to answer the detailed questions you are asking. People are expected to learn the background on their own, some of us have not done our homework yet. If you have trouble with this summary, you should make a better effort to find a summary you can understand, not discard the report. This web site has a number of basic summaries that you could start with. The scientific position on causation of sea level rise is discussed in the NAS report. Obviously, if humans cause the warming and warming causes sea level rise, then humans caused sea level rise. Roy Spencer is one of the 3% of scientists who disagree with the consensus. Why should I listen to the fringe crowd, especially someone like Spencer who has been shown to be wrong any number of times in the past? In any case, recently he has conceded that his data now matches the surface record that he criticized in the past. Other scientists corrected his mistakes.
  29. More evidence than you can shake a hockey stick at
    Your question about record highs is a good one. Surely this is a simple enough figure to be readily available from most European countries
    Since 2002, when the website below was born, there have been more record-breaking hot days than cold each year for the list of cities, towns and airports around the world. http://www.mherrera.org/records.htm The record-breakers for the current year are here. http://www.mherrera.org/temp.htm That page also includes a list of 1600 or so (from memory) of the cities and towns in the database with there min/max temps (but no dates).
  30. Grappling With Change: London and the River Thames
    Michael, I don’t think that the Australian Government would be very impressed with your derisive “ .. dating back to only 1993 and covering only 12 islands .. ” comment about their The South Pacific Sea Level and Climate Monitoring Project (Note 1). You seem to be suggesting that the coverage they have established for that part of the globe will provide inadequate data. The Monitoring Network (Note 2) comprises: “- Sea Level and Meteorological Monitoring Stations. The current network of 12 robust and low maintenance Sea level Fine Resolution Acoustic Measuring Equipment (SEAFRAME) monitoring stations is providing excellent service. All parameters having an effect on sea level (wind, air and sea temperatures, atmospheric pressure) are being sampled at one second intervals. Sea level readings are taken and averaged over three minutes and meteorological data is collected and averaged for 2 minutes at the hour. - CGPS Monitoring Stations. The Continuous Global Positioning System (CGPS) network monitors vertical movement in the earth's crust, such as subsidence or tectonic shifts, at the SEAFRAME tide gauges and adjacent land. Sea level data can then be adjusted to compensate for the earth's movement to within a millimeter, enabling the absolute sea level to be determined.” Perhaps you’d like to show how the monitoring network used by Church & White (2006), Holate & Woodworth (2004) and Leuliette et al. (2004) to produce the data used in the NAS graph compares. You say that “The NAS study .. has real sea level data on page 168” but what I see on that page is a graph that purports to represent changes in annual mean sea level as determined by tide gauges and satellite altimeters, along with rate of sea level rise estimates. How reliable are those estimates, arrived at following statistical manipulations undisclosed on that page? Far more important to our discussion is the statement just above that graph “Distinguishing the effects of natural climate variability from human-caused warming is one of the challenges of understanding the details of past sea level and anticipating its future course”. You might also consider Dr. Roy Spencer’s “My Global Warming Skepticism, for Dummies” comment (Note 3) “ .. to the extent that warming occurs, sea levels can be expected to also rise to some extent. The rise is partly due to thermal expansion of the water, and partly due to melting or shedding of land-locked ice (the Greenland and Antarctic ice sheets, and glaciers). But this says nothing about whether or not humans are the cause of that warming. Since there is evidence that glacier retreat and sea level rise started well before humans can be blamed, causation is — once again — a major source of uncertainty” – “hear hear” to that.. You may like to read his book “The Great Global Warming Blunder: How Mother Nature Fooled The World's Top Climate Scientists”. NOTES: 1) see http://www.bom.gov.au/pacificsealevel/ 2) see http://www.bom.gov.au/pacificsealevel/technologies.shtml 3) see http://www.drroyspencer.com/my-global-warming-skepticism-for-dummies/ Best regards, Pete Ridley
  31. Berényi Péter at 23:54 PM on 10 August 2010
    Temp record is unreliable
    #99 Ned at 21:31 PM on 4 August, 2010 As a reminder, BP's figures (like the first one in his comment above) are not particularly useful as long as he continues to use simple averages of the GHCN data set. In a sense that's true. But it is good for getting an overview, the big picture if you like. Also, if adjustment procedures are supposed to be homogeneous over the entire GHCN, this approach tells us something about the algorithms applied, if not about the actual temperature trends themselves. However, with a closer look it turns out there are multiple, poorly documented adjustment strategies varying both over time and regions. Some adjustments are done to the raw dataset, some are only applied later, some only to US data, some exclusively outside the US, but even then different things are done to data in different regions and epochs. A gridded presentation is indeed an efficient way to smear out these features. On the other hand, it is still a good idea to have a closer look on intermediate regional and temporal scales if one is to attempt to identify some of the adjustment strategies applied. For example here is the history of temperature anomalies over Canada for a bit more than three decades according to three independent datasets (click on the image for a larger version). I have chosen Canada, because of data availability and also because this country has considerable expanses in the Arctic where most of the recent warming is supposed to happen. The three datasets used were
    1. GHCN (Global Historical Climatology Network)
    2. The National Climate Data and Information Archive of Environment Canada
    3. and Weather Underground, an independent weather portal company (a spinoff from the University of Michigan)
    The three curves have some family resemblance, but beyond that their physical content is radically different. Weather Underground shows an almost steady decline since 1989 (that is, a 0.8°C cooling), GHCN a huge warming (more than a centigrade in three decades, almost 1.27°C in five years between 1994 and 1999) while Environment Canada something in between with practically no trend since 1985. Up to about 1995 the three curves go together nicely. With some offset correction (which has no effect on temperature anomaly trends) they could be brought even closer. The same is true after 1998. Therefore in this particular case most of the action happened in just four years between 1995 and 1998. In this period the divergence is very noticeable, so the next thing to do is to have a closer look at these years in Canadian datasets and to determine the exact cause(es) of discrepancy. Now I do have all the data necessary to do the analysis at my fingertips. Unfortunately I do not have too much time for this job, you may have to wait a bit. Neither was it always easy to collect the data. My IP has even got banned from Weather Underground for a while because they might have noticed the work the download script had been doing. Anyway, I have no intention to publish their dataset (as long as it stays put on their website), I just use it for statistical purposes. The spatio-temporal coverage patterns of the three datasets are different inside Canada. Weather Underground, understandably, has an excellent recent coverage, getting sparser as we go back in time. Fortunately for some sites their archive dataset goes back to January, 1973 (e.g Churchill Falls, Newfoundland). They also use WMO station numbers (at least in Canada), which is convenient (the connection between four letter airport identifiers and WMO numbers can get obscure in some cases). It is just the opposite with Environment Canada. Their coverage in early times is even better, than the previous dataset's (they go back to March, 1840), but it is getting sparser as we approach the present (unfortunately their station identifiers are different from those used by either GHCN or Weather Underground). This tendency of station death is even more pronounced in GHCN. It is not easy to understand why. GHCN has a particularly poor recent coverage in the Canadian Arctic, although this area is supposed to be very important for verification of computational climate models (Arctic Amplification and all). It is funny, that even the raw map used by GISS misses a fair number of the arctic islands that belong to Canada and shows sea in their place. At the same time Arctic coverage of Environment Canada is excellent. Their data are also said to be quality controlled and of course digitized. Why can't it be fed into GHCN? Looks like a mystery (I know there used to be a war between the two countries back in 1812 when seaborne British terrorists ate the President's dinner and set the White House aflame, but I thought it was over some time ago). Anyway, the very practice of making adjustments to a raw dataset prior to publication is a strange one, which would be considered questionable in any other branch of science. But should adjustments be done either way, if their overall magnitude is comparable to the long term trend, anything is measured but the trend itself. The double adjustment to raw Canadian data also makes understandable why USHCN have got a different treat than the rest of the world. It would be pretty venturesome to meddle with US raw data directly for the US, despite the recent legislative efforts of both major parties to put an end to this preposterous situation, is still an open society, more so than most other countries of the world. Therefore it was advisable to introduce US adjustments only in v2.mean_adj, which is a unique feature, not done for the rest. As the US is only a tiny fraction of the globe, at first sight it does not make much sense to go into such pains. But without the 0.52°C upward adjustment of the US trend, data from there would get inconsistent with neighboring Canadian ones. What is more, it would be somewhat inconvenient to explain why the US does not have this warming thing, but still needs cap & trade. It is also noticeable, that the strange divergence, if global, does not increase one's confidence in computational climate models parametrized on this very dataset.
  32. Why I care about climate change
    #124: "science will triumph over the establishment's beliefs, but whereas it didn't happen within Galileo's lifetime, hopefully the establishment will see the error of its ways sooner than later" Sadly, it took over 200 years for 'the establishment' to see the error of its ways. By 2200, we'll have 800 ppm CO2? I teach high school science; as a new school year begins I remind myself of this: four out of five Americans (79%) correctly respond that the earth revolves around the sun, while 18% say it is the other way around. These results are comparable to those found in Germany when a similar question was asked there in 1996; in response to that poll, 74% of Germans gave the correct answer, while 16% thought the sun revolved around the earth, and 10% said they didn't know. When the question was asked in Great Britain that same year, 67% answered correctly, 19% answered incorrectly, and 14% didn't know. Science may indeed triumph some day, but there always seems to be that last 20-25% who will never get it.
  33. Talkin bout the Skeptical Science phone apps
    Speaking of which. John, you may have noticed a commenter at the Guardian going by the nickname of PaulInOz1 who was highly critical of you and your article. Turns out he's Paul Ostergaard of Aeris Systems, the developer of Our Climate. There's another "contrarian" called PaulInOz at Guardian CiF who's been there for a while now, so it's not sure if he's the same guy, but PaulInOz1 only started posting on August 7th. Pretty low if you ask me. He's been banging heads with some of us (in one he kept repeating "Shame on you" at me), and one in particular called onthefence. Search through the Our Climate reviews at the Apple store and you'll find a review by an "on the fence" singing the praises of Our Climate. OurClimategate, as far as I'm concerened.
  34. Grappling With Change: London and the River Thames
    Typo: should be page 186 in the NAS report.
  35. Grappling With Change: London and the River Thames
    Pete: You cited a non-peer reviewed article by a single author dating back to only 1993 and covering only 12 islands as more authoritative than the US National Academy of Sciences? The entire paper consists of eyeballing data, no analysis is performed. If this is what convinces you have a good day. The NAS study Doug linked has real sea level data on page 156.
  36. Waste heat vs greenhouse warming
    RSVP at 18:47 PM on 10 August, 2010 I'd say that they are products RSVP, and we should be careful not to over-categorise the outcomes of scientific advance. We might say that in the broadest sense the aims of science is enhancement of human wellbeing (even if in reality scientists are more focussed on rather specific outcomes, many of which may have commercial motivations). For "products" in the commercial sense this might relate to direct benefits of things (like cars and flights and duvet covers), and the slightly less direct benefits in relation to profits and employment, and then the overall benefits to societies from economic wellbeing. Publically-funded research is less likely to result in products in the sense of discrete things (although a lot of this does do just that in relation to technology transfer of publically-funded research outcomes to industry). But the science that underpins the development of vaccines or cancer therapies or antimicrobials can be considered to yield "products" that have enormously positive contribution to human wellbeing. I would consider that the scientific outcomes on CFC catalytic destruction of stratospheric ozone is a "product" in this sense, if rather less directly so, since it leads to understanding that informs productive economic and political decisions which enhance human wellbeing. Apollo is an interesting example. I certainly wouldn't say that the future realities of whether or not there might be commercial voyages to the moon, is any reason to question the science, for at least two reasons. First, it might be a reason for questioning the motivation underpinning the scientific effort. Much of this was political, and one could argue that the "product" (enormous prestige and enhancement of personal satisfaction in the American population during the 1960's) had huge value. More generally, the science stands on its own merits. One can't predict necessary outcomes of scientific research, but Apollo was an important step on the path for development of technologies in rocket science, computers, satellite remote sensing and various elements of materials science, and understanding of human physiology.
    Moderator Response: I think this conversation has gone far outside the topic of waste heat. Please, everybody get back on topic.
  37. Grappling With Change: London and the River Thames
    Michael I don’t see that we are splitting hairs on the fundamental issue. This is whether or not emissions of CO2 into the atmosphere arising from our use of fossil fuels has made, is making or will make any significant contribution to past, present or future global climates (or weather events). Discussing whether or not it is correct to refer to opinions on this issue as hypothesis, theory or even law is pure semantics so let us stop wasting time on it. I’m not impressed by the numbers argument (scientific consensus) in supporting conjecture, only by what I recognise as hard evidence and am always suspicious of statistical manipulations and people with political motives. Your “list of predictions” includes such speculation and the first one, “sea level rise” is something that I have been involved in recently as I have been reviewing a draft book on the subject of sea level change being written by a couple who are not scientists. They, like you, obviously QUOTE: .. think these are "significant human-made global climate change" .. UNQUOTE but this does not make it a fact. May I suggest that you take a look at the 2009 article “SOUTH PACIFIC SEA LEVEL: A REASSESSMENT” at the New Zealand Climate Science Coallition site (Note 1). I particularly like that column “Years with zero trend” in Section 3 Conclusion. Doug, I have had quick look at the NAS report and so far have found nothing that I haven’t seen before, either in AR4 or the numerous papers and articles that I have read during the past 3 years. I may be able to make time for a further read but looking at some of the over 200 references mentioned there to “uncertainties” and “estimates” about those horrendously complex global climate processes and drivers gives me a hint that I’ll be wasting valuable time. I was disappointed to see virtually nothing about assumptions made. NOTES: 1) see http://nzclimatescience.net/images/PDFs/spsl3.pdf Best regards, Pete Ridley
  38. Confidence in climate forecasts
    Johnd: Around 1900 Arrhenius calculated a climate sensitivity (by hand) of 4.5 C/W2 without knowledge of the weather that you claim is required for that calculation. His number is still within the range of accepted values. The models of the 1970's and 1980's predicted, with skill, current warming, arctic amplification, sea ice loss, Arctic/Antarctic anamolies, etc. These models did not have the weather knowledge you claim is required. The forecast of weather, both short term of weeks and long term of a few months or years is simply different from the long term forecast of weather out decades. Weather is chaotic while climate is not. I was going to refer you to the "weather is not climate" page but I see you are a frequent visitor already. Perhaps it is worth another read.
  39. Waste heat vs greenhouse warming
    Chris Similarly, with global warming, whether it is caused by men, women or nature, there will be no way to proove it, even if people take action and a detected warming trend goes away. I have tried here to help, but cannot afford to spend time writing things that get deleted. So this is my very last post. I salute you and wish you all the best.
  40. Waste heat vs greenhouse warming
    Chris "I'd say they're knowledge an impulse to understand difficult phenomena and to apply this knowledge and understanding productively. " The application of science has its impact on products that in the end must work. In many cases, customer satisfaction is a reliable indicator that proves the science out. Global warming, the size of the ozone layer hole, whether they went to the Moon or not,... these are not "products" passing the scrutiny of society at large. It is applied science yes, but not the same. Going to the Moon could be a product, and the day it is, very little skepticism on this issue will remain. You could still however question whether Apollo was for real, but how relevant will it be? On the other hand, the more time that goes by and there is no commercial voyage to the moon, the more reason to question the science.
  41. Three new studies illustrate significant risks and complications with geoengineering climate
    Lewis, I can't reliably answer your questions but am inclined to believe the authors are speaking of reactive, interventionist techniques, possibly leading to failure to effectively deal with what spawns the intervention. One of the authors (Morris Judd) has a blog post mentioning the publication of the paper, Geoengineering Article, and seems responsive to folks stopping by with comments. For my part, if we can't avoid putting things in the atmosphere it seems to me most conservative to focus on directly removing what we've added, not exactly geoengineering in my book so much as tidying up as we go along. Which of course begs the question, how may we avoid adding what we must remove? If it's cheaper not to add at all that's better than going full circle.
  42. Confidence in climate forecasts
    Doug @ 108 - great graphic over at Jeff Masters' blog, very interesting to see how it compared with the 2003 European heat wave. I have one eyebrow raised.
  43. Three new studies illustrate significant risks and complications with geoengineering climate
    Doug - thanks for the synopsis above - sadly the text is "currently unavailable" so I'm hoping you can clarify some points. As one who'd still be opposing Geo-E if there were any credible argument that excess airborne GHG stocks could be removed by natural sinks before the feedbacks gain enough momentum to run amok, my interest is in effective sustainable Geo-E techniques. The meaning of "antecedent criterion" is unclear - does it refer to "a return to conditions prior to the problem" ? Or perhaps to "problem being insoluble without intervention" ? The "future state constraint" appears to generalize an assumption that all Geo-E options generate permanent change from the original condition. True in the sense that you can't step in the same river twice; untrue in that a gigahectare of forest carbon sink would both retore pre-industrial planetary tree cover and would help cleanse the atmosphere. Also untrue for albido restoration via 'cloud brightening,' where miniscule sea-salt particles, lofted in minute seawater droplets, would reliably be rained out within a few days, and would be generated to do so over the oceans. So is the paper generalizing unjustifyably, or is it just that the synopsis not able to express a more nuanced argument ? If the latter is the case, could you describe it ? Regards, Lewis
  44. Why I care about climate change
    ...Indeed its fair to say that today's establishment is ruled by the all powerful economic "realists". Once again science will triumph over the establishment's beliefs, but whereas it didn't happen within Galileo's lifetime, hopefully the establishment will see the error of its ways sooner than later.
  45. Pluto is warming
    Two questions: 1. Where are the scientific citations for "What the science says..." section? 2. The following statement has major logical flaws: "Any Plutonian warming cannot be caused by solar variations as the sun has showed little to no long term trend over the past 50 years and sunlight at Pluto is 900 times weaker than it is at the Earth." First off, why is it necessary for the sun to undergo long term variations over several decades for solar variations to affect Pluto? That is, why are short term variations completely irrelevant? For an extreme example, let's say the temperature of the sun doubled overnight and stayed that way for a year, only to fall back down to normal the next year. Does anyone seriously believe that such an extreme (but temporary) solar temperature jump wouldn't affect Pluto's temperature? Secondly why does the fact that the sunlight is 900 times weaker on Pluto necessitate that Pluto is not warming due to solar variations? Presumably the fact that Pluto is 500 times smaller in mass than the Earth with essentially no atmosphere plays a role, no?
  46. Why I care about climate change
    gallopingcamel @ 122 You fail to see the irony of your last post. Back in the day of Pope Urban VIII the establishment was based on theology. Galileo's theory of heliocentrism was based on science and the empirical observations that he could make. Who ended up being right? Galileo with his damnable science...
  47. Remember, we’re only human
    a most excellent post! the most insightful sentence is "What is needed is a radical change in how we see ourselves and our place on this planet." in my opinion, Cosmology should be a required course in high school and college. Not just evolution that has happened on earth with regard to our life forms but stellar evolution. the fact that the elements that make up life on earth were formed in stars billions of years ago is truly a tremendous revelation. if we all come to the realization that life on this planet is so rare and it took close to 15 billion years to get here causes one to pause. although i don't believe it, we might be the first fruits of that evolution and could be the only advanced civilization in the galaxy or universe. upon coming to that realization how frivalous are wars and religious/political squabbles? are we so ignorant and arrogant to destroy ourselves and snuff out the only life in the universe? sometimes i think it might be in our best interest to find life on another planet so that we put our existence in the proper perspective. and i agree with the first post by BP and all my beliefs in christianity are not nullified with my understanding of stellar evolution and the observations of our universe. the incredibly precise constants that are required to make life as we know it couldn't have happened by chance. the more i learn about the cosmos the more i realize that there must have been intelligent design and this cries out for a creator. i hope that our struggles now are just a turning point for our planet and only through education can we push through this to a new level of enlightenment and purpose. AGW is just one of the issues we are wrestling with and the good news is the cosmos has a funny way of exerting its influence no matter what we may 'beleive'. our only hope is to raise an educated public to discern which issues to focus on and which ones are real.
  48. gallopingcamel at 14:36 PM on 10 August 2010
    Why I care about climate change
    JMurphy (#121). Great work! You have listed the "learned fools" who know what they need to say to keep the gravy train rolling. All the experts in the establishment supported Urban VIII but history has forgotten who them.
  49. Post your blog review on the radio podcast: Long Term Certainty
    Suppose you go to the Star City casino on Friday night and place a bet at roulette. I just fixed another point, now people in Sydney will know what you are talking about!
  50. Post your blog review on the radio podcast: Long Term Certainty
    Who will win the NRL Grand Final in September? I have just fixed up your example for you.

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