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Dawlish

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Everything posted by Dawlish

  1. You do absolutely right and long may you do so! However, I invoke Godwin's Law here! Paul
  2. When you are talking about "so many people" Cap'n, you are actually referring to a small minority of scientists. There may be hundreds, but when you measure that against the many tens of thousands of scientists that accept AGW, then it is a small minotiry! By not fully accepting C02's role in causation, I'm actually in the minority, but the weight of the majority has been slowly persuading me, over the last 2 years in particular. To change one's mind is very, very difficult. Paul PS Hope I've got my "so many people's" actual focus right there!
  3. I agree. There is such a difference, for me, in the models being used to produce forecasts out to 16 days and the models being used to predict climate out to 100 years. The variability in the atmospheric models, with slightly different initial conditions producing massive differences in well under 16 days time, is not reflected to the same degree in climate models IF and only if, C02 is the main cause and there isn't another cause that is greater and will override it. The reason for the difference is the inherent simplicity in the variables used in the climate models, compared to the complexity of the variables being modelled in, say, the gfs models. If C02 is the main culprit in GW, the models will, to the error limits that define them, probably be correct. As PM3 rightly says, the hindcast accuracy is good. The only problem with the models, for me, would be if the main model input were to be masked by another factor (solar output, natural cycles, astrometeorology?? etc.). That's why I feel, at my personal odds of 1/6 C02 being the main cause, that the predictions of the climate models are more likely to be correct, than not. Paul
  4. Don't you dare go for brevity! We're enjoying your contributions! Paul ( and I've been called a lot worse than Paul on here, I can assure you!)
  5. Tha article hound at his best! I like that realclimate site, it teaches you and make you think and although the comments following the article, take some time to plough through, there's a lot of commonsense in the opposing views. Perhaps the one which I agree with the most was this combination of nice hunour and knowledgeable comment: "........I tend to be more interested in the really big patterns, like the natural greenhouse effect keeping us warmer & adding to it likely increases that warmth. Past mass extinctions caused by runaway GW (then, obviously, triggered by a convergence of natural events), resulting in few left to breathe out CO2 (among other constraints), leading to stabilization and retreat back to a climate more hospitable to a wide range of biota. See: http://news.nationalgeographic.com/news/20...18_fossils.html These make so much sense & are so dangerous in their implications, that the burden of proof should be on the contrarians or skeptics to prove these things are not happening. And even if they do, we still have many many other reasons, aside from GW, to reduce our actions that increase GHGs. So, to the extent that we're smart and able, let's ease up on the GHG trigger, or we might be shooting our own descendents. But I do appreciate the meticulous ongoing work to understand in excruciating detail and minutia just how we are harming ourselves". Comment by Lynn Vincentnathan With the bulk of scientific opinion favouring a continuation of the warming trend and the bulk of scientific opinion favouring CO2 as the main cause, I do think it is up to the sceptics (I hate that "k" in sceptics!!) to prove it is otherwise. Paul Devonian - I agree with you entirely. The whole debate has been good and it will continue; just a note: no need to quote the whole article for a one line comment. I always cut it down to what I am commenting in, or just add a general reply, instead of replying to the whole article :lol: Hope the anniversary went well, Cap'n.
  6. That's where careful and dedicated amatuer recording really comes into its own. Any recording error (and there will be little) is drowned by the wealth of data. Thanks TM. Long may you and many others continue. Is anyone capable of putting this in a graph, running a regression analysis on it and seeing what the trend is and how significant it is? I can't do the techie bits! Paul
  7. Nice reply Cap'n. When you investigate CO2, look, as well, at increasing partial pressure, as the concentration of the gas increases. It may offset the release from the oceans' warming. Are you actually bang on the fence, Cap'n? ie would you propose that C02 has an equal chance of being the main cause as it has of not being the main cause? I always like to use odds in these circumstances, it allows a much clearer picture of preference, or belief, to be painted, whilst allowing the proposer to show that he/she has an open mind still (that "1" in the odds signifies that one recognises that what one is proposing has a measure of doubt). I go 1/6 C02 being the main cause, 7/1 it is natural cycles, 12/1 it is changes in Solar output, and 20/1 the field. At the start of this year, I was saying 1/4 C02, which shows how my thinking has changed, as I've learned more. Paul
  8. Been a very nice day down here. Up to 12C in a very light Westerly. Some nice sunshine and good visibility. Beginning to feel cooler now. I saw 3 red admirals in the garden and I killed a wasp, which was in the Kitchen!
  9. I don't recognise that scenario; nah; never happened to me, ever; nope; well, not since yesterday!
  10. If I could agree more, I would, but I can't, so there you go. I scraped the physics "A" level, hated the short period of undergraduate physics I suffered and finally took a degree in the Earth Sciences - which any meteorologist worth their salt will tell you, doesn't count a scientific fig! They told Prof Manley the same for years as he was a Geographer too....but they're scoffing on their own verbal stuff now!! Just enjoy the debate. We are all at different stages, but that doesn't mean we can't learn from the most sage, or the newest newbie, or the most hardened opponent. It is hard to believe the amount that I've learned about GW since beginning to discuss it on the Internet. Even people actually working in climatology cannot keep abreast of every branch of the subject and there will be climatologists who will know less than the readers and writers on this thread do about some of the more arcane topics that have been argued over on here. Paul
  11. Thanks Stephen, I was looking for that on the synoptic chart, but it must have been a chart for just before the temperature rose. It was still saying 10C in your area. Meteocentre still hasn't picked up the change, although it could be very localised: http://meteocentre.com/analyse/map.php?hou...g=en&map=UK Thanks for alerting us to it. It really is interesting, in that the fohn/lee wave is embedded in that occluding front. Did you notice the clouds, before it got dark? Any lenticulars, or was it 8/8? Paul
  12. For me, Ice Age Now is one man's crusade against the vast body of scientific opinion that accepts that the world is likely to continue to warm. realclimate is that vast body of opinion. Personally, I don't think it is biased. The contributers are climate scientists who are working on climate research right now; many of them are leaders in the field. The site reflects the overwhelming scientific belief that the world will continue to warm, rather than the site itself being biased. If anyone goes lookig on the site for articles saying the next ice age is imminent, they aren't going to find many (there are some responses, however), because the vast majority of climate scientists don't believe it is. I happen to agree with that body of opinion. Many of them (not all) believe that C02 is the cause (I took it for granted that you meant an open mind as to AGW. You write well and it's good to keep that open mind. I favour C02 being the major cause, but I'm not yet convinced and I don't think the conclusive evidence is there, yet, to convince me), but they are by no means the only voice in the AGW debate on there. Paul
  13. I see it Stephen. How strange it looks. It must be a lee effect, as you imply.
  14. Agreed, however the Global Warming trend per se is conclusive. It is not reflected in every glacier, on every continent, just as it is not reflected by a linear, similar, warming trend in every area on the globe, but the world is warming. I take your point entirely about the limp 30 glacier sample of the world glacier monitoring service. It must be down to costs. 500 would be far better! Realclimate, a site which appears to have good provenance, has some more excellent data on glacier retreat (did I quote this site earlier??). Nice graphs and piccies, again. http://www.realclimate.org/index.php?p=129 I've just flicked around Garry Braasch's site again (link above) and the photography and juxtaposition of glaciers over time is just terrific to see. Paul
  15. Thanks for the article cap'n. There are just no hard and fast rules; glaciers in fairly close proximity, but different catchments can be doing dissimilar things and as the article says, monitoring in some of the remote areas is difficult and all we have are snapshots. Also, if 2/3 of Himalayan glaciers are melting, as I quoted (maybe the figure could easily be argued with; monitoring is not great in these incredibly remote areas), it means that 1/3 are not and some will be advancing. I'd just go with the best data for the overall world picture. The mass balance figures (I know 30 glaciers isn't that many, but they are sampled from a global perspective and the sampling appears to produce statistically significant results) show the worldwide trend overall and it would be difficult to argue that these global trends are not due to a warming climate, despite some glaciers not fitting the overall melting trends. I hope the anniversary goes well! Paul
  16. Yes, you are right, Cap'n. We must never take individual events as proof, or otherwise of global warming, despite some saying that the scientific world attributes everything to GW. they don't, it isn't and it shouldn't be. There are glaciers that are surging at present, in different areas of the world, as well as glaciers which are retreating due to ablation, or reduced snowfall, but these are the exceptions. Overall, glacial retreat, by melting due to warmer temperatures, is far more common than retreat by any other means, or of surging. 67% of glaciers in the Himalyas are in retreat: http://assets.panda.org/downloads/himalaya...sreport2005.pdf Perhaps the most worrying area of all are the Andes, where glaciers provide much fresh water: http://www.environmenttimes.net/article.cfm?pageID=14 In terms of mass balance, the world glacier monitoring service show some compelling statistics; 2004 is the latest year they have data for, but the graphs say it all: http://www.geo.unizh.ch/wgms/ http://www.geo.unizh.ch/wgms/mbb/mb04/sum04.html Wiki echoes these changes and has more data. I have no reason to doubt this particular Wiki stuff. http://en.wikipedia.org/wiki/Retreat_of_glaciers_since_1850 Garry Braasch's site has some great piccies, that the coldies and warmies alike will love!: http://www.worldviewofglobalwarming.org/index.html Paul
  17. Good grief. Could you imagine the utter chaos if that kind of winter was ever to be repeated with 60m people now in the UK and 32million cars - mind you I suppose we could use the Thames as an extra few lanes to the Embankment!
  18. Thanks for the input. I'm happy to be damned with the faintest of praise! I don't mind, mate honest, it's a good way of making a point; just steer away from the personal, if you would. :lol: ). What I said really does make complete sense, Steve and you are looking at this from the point of view of an amateur forecaster (as we all are) defending amateur forecasters and thus missing the point completely about accuracy. I understand very well how you and others are pull together all sorts of strands to produce a forecast. I also understand your frustrations at 7+days out being inaacurate. I understand all too well that amateur forecasters may see what I say as a challenge. i'm one of them and the impossibility of being consistently accurate frustrates me to hell too. However, it does not change the fact that accuracy is the thing that is lacking - in ALL amateur and professional forecasting at 7+ days. If I didn't say that, what do people really think? Do they think that the amateur forecasts are in some way "good", or "great"? Well, yes; when judged on the content of the meteorology. I've said many times that all the LRFs and medium term ones are that. I have great respect for the learning that is displayed, but all too often that "good forecast", or "great forecast" has an element of outcome in the praise. Unfortunately, much of the outcome is judged, on here, by the amount of the forecast devoted to predicting when it will get cold. I'm pretty sure that drives the majority of winter forecasts on netweather. Let's see if I can get the cold bits right, rather than let's assess what this possible evidence is showing me and see if I can come up with a forecast, as a result. Forecasts can only be good, great, or whatever, if they stack-up, over time, with a statistical accuracy of 75% or higher. That's what I'm looking for in 7 day+ forcasting and that's what I'm looking for in LRF. No-one is achieving that with consistency, therefore the tools that are being used are not good enough, or the forecasting is not good enough. It's not sitting on the fence, quite the opposite, it is stating a truth so we can judge these forecasts in the correct light. If I rub you up the wrong way (odd term to use in this excellent debate) maybe it's because you don't agree with me, but the only way to challenge back is to produce the evidence that ensembles, or any other "tool" is used to produce forecast accuracy, or accept that what is being done in amateur forecasting, produces results which are simply not accurate, over any period of time and against any measure. I know that would be hard to accept, but the evidence for the veracity of my statement is overwhelming. I wouldn't make it otherwise. Paul PS Off for 2 days to do "great work" in North Somerset. Hope it doesn't snow!
  19. I understand Phil, but with respect, the number of members favouring a particular run makes no difference to the probability of its outcome, unless that outcome showed sinificant success over time, based on that number of member runs supporting it. "caution when interpreting the synoptics" only means so much. I agree that forecasting in settled conditions is much easier than in changing conditions ie forecasting the continuation of a blocking high is easier than forecasting any other synoptic situation. Good debate I appreciate the views. I hope you see that accuracy is how I judge usefulness and low accuracy = low usefulness. Paul
  20. I know and I understand. It wouldn't help the current accuracy by issuing the challenge to me! I wish forecasting accuracy was higher, but it isn't. My spots have nothing to do with this, of course, they are only for events, as I feel there is no accurate means of forecasting mid-range on a regular basis. They aren't statistical though; instead they involve time-delayed coincidence. The fact that ensembles are issued doen't imply they will improve forecasting accuracy, Decisions are made by gfs as to what information to release from the models. There may be a demand, but is it for ensembles because they increase forecasting accuracy? The proof of the pudding is in the forecasting accuracy....... which is low. Paul
  21. Hi Nick, "Ill informed" wouldn't be right. I am well informed. I understand ensembles, control runs, mean ensembles, very well. I understand the mechanics of numerical forecasting well until it gets to the maths(!) and I have a good knowledge of the gfs ensembles and their production. It is just that I question their use in informing accurate forecasting - especially in the medium range. It isn't that I'm ill informed - it is my knowledge of ensembles that allows me to sensibly question - it is that I've decided that they are not useful enough to forecast at T+200+ with accuracy. Your link is interesting, but without saying how accurate that mean ensemble is, at a projected forecast time, what is the real point of it, apart from simply being interesting? Sometimes we have these ideas that things, such as ensembles, are useful in forecasting, but are they of use in forecasting, or are they of use in justifying the forecast that is being made? Paul He now runs a company selling the information to corporations instead. It is a private company, so it does not file public accounts, but I read that his annual income was up to £5m a few years ago. He certainly gained intial publicity doing just what you say, Kippure (Solar activity, rather than just sunspots, I think) and was on the TV several times, maybe 5-10 years ago. I don't know whether he still does the same! Paul
  22. Sorry, BB, you've misunderstood me. I was talking, throughout my post, of forecasts 6/7+ days out, not up to +3. I'm sure you are right that they are useful up to +3 days out and there, because the accuracy of the forecasts, to 3 days out, is good. Do you think it is preposterous that the forecast accuracy of 1 week+ forecasts, shows that the use of any current method is not, statistically, particulary useful? I always judge the usefulness, or otherwise, of forecasting techniques on their accuracy, not on their potential, or on the fact that people's anecdotal evidence, or belief, is testimony to accuracy. I realise that this is a statement which will horrify people who feel that what people are doing on here, with LR gfs charts, is forecasting and getting results. In general, we don't; we hazard reasonable guesses and the better people qualify them all the time. "nailed on" and certainties are not terms best applied to reading the runes of the gfs. Probability forecasts would be so much better. It has always been my premise that any forecast above, say, 7 days, is not accurate enough to trust, using any methods presently available. They are just not consistent and if the use is not consistent, what actually is the use, as one can't know which forecast is likely to be more accurate than another? The thread title is "General Model Discussion" and that's exactly what we do on here; discuss, postlate, try. In the poorest sense, the use of ensembles is just as good...which actually means just as bad....as any other method currently being used at 1 week+. If there was an accurate method, the Met Office would be using it with demonstrable accuracy percentages. They aren't. Thus; a viable method does not exist - yet. Just to head off one branch of possible criticism on that; if anyone thinks that is a post that says "don't bother trying", then they just don't know my writing! Always bother. Always experiment. Don't be put off by any criticism, but accept the current weaknesses of what you do. There is a means out there of forecasting accurately at T+200+. It just hasn't been found, monitored, evaluated and exploited.......yet......unless Piers Corbyn really has cracked it. I do wish he'd make his research public. Paul
  23. I understand that completely and I have been interested in the ensembles before, for exactly that reason, but there's a logical inconsistency in there though. If the whole set of runs at, say, T+144, or even more distant proves to be pretty hopeless in 6+ days time - and a lot of TWS's excellent tracking shows this - then the ensembles were not actually providing a great deal of useful data at all, no matter when the convergence took place. A good measure of this would be to forecast, using the times when the divergeance appears to start. Forecasts over a reasonably long period of time, using the control run, at that point of divergence, would show whether this point of divergence was of any practical use, or whether it is another of those "tools" that would be just as good left in the shed as being used! Can it actually be used for forecasting? If it can't, it is there as a discussion tool and no more. I don't think it is useful, therefore I have decided not to use it. If anyone has any data on it's usefulness, I'd be really interested in seeing it. In the end, there are a whole load of these "tools" out there, which are often referred to, with the implication that their use is obvious. The statistical lack of accuracy, in forecasting more than 7 days ahead, would suggest they may be of nothing like the usefulness that is often simply accepted, without a great deal of question. Paul PS The 06z takes the cold further East around the 12/13th again and the rest of the run is much milder.
  24. I don't, personally, take any notice of ensembles. The charts will always change T+120+ and, in fact, to 13th March, despite the variability implied by the ensembles, that High pressure over the UK has been constantly there, for a week. I mean, if, for instance, someone said that "beyond the reliable timeframe" whatever that competely nebulous phrase means, the gfs is unpredictable, why then does the same person talk ensembles? If the chance of the control run coming off is low, the chances of any ensemble run coming off is similarly low. In these cases, the control run is no better that any single ensemble run. Most of the time, that is true of T+200+ and I often use the phrase "white noise". When ensemble divergeance, or possibility is quoted further away than T+200+, I just smile and shake my head. Control/ensemble/time of day run means very little and forecasting accuracy, which si what I am really interested in, is demonstrably far too low to trust. If it wasn't, the Meo Office would produce a reliable 1/2 week ahead forecast and we'd plan our activities by it. They can't. hence the lack of use of any run as a predictor at T+200+. Hence the almost complete unreliability of ensembles. Ensembles are mentioned so much, but, at the time that 12/13/14 High was established on the charts (for me), several days ago, the ensemble runs have, as pretty much always at that distance, been all over the place. The fact is mentioned about every 10th post, often with an implication that there are times when ensembles are useful. I know they can show a degree of convergeance a particular time in the future, but I think it is worth questioning the relevance of that convergeance and its usefulness in forecasting. I'd be interested in hearing other views on this. Paul
  25. Dave, just a question; do you think that GW is not happening, or do you think that AGW is not happening. The confusion is the main weapon of climate change sceptics. Paul
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