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uk.sci.weather (UK Weather) (uk.sci.weather) For the discussion of daily weather events, chiefly affecting the UK and adjacent parts of Europe, both past and predicted. The discussion is open to all, but contributions on a practical scientific level are encouraged. |
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#11
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On Jun 12, 8:35*pm, wrote:
Keep it coming, Mr McNeil.....!! I'm sorry you don't fooly appreciate my gift but here goes: Earthquake size is expressed by its magnitude. Magnitudes usually are measured from the amplitude and period of seismic signals as they arrive and are recorded at a seismic station. For a given earthquake, the amplitude decreases with increasing distance (due to attenuation of the signals) and a distance dependent correction is applied when computing magnitude to result in one magnitude value for each station. Earthquake size does not depend on where an earthquake was recorded, this is contrary to felt effects - the intensity - which decreases with distance from the earthquake source. Several methods exist on how to compute magnitude - in principal, all methods provide the same or a similar value. However, there are fundamental differences on how these magnitudes are computed (sometimes resulting differing magnitudes). Here is a short summary, describing various magnitude types: ML: The local magnitude ML is computed for earthquakes, which occurred relatively close to the recording stations. Typically this is done for earthquakes within a few hundred kilometers between the earthquake and the recording station. The first magnitude scale developed 1935 by Richter (the 'Richter-Magnitude') is such a local magnitude; even today earthquake size is commonly given as 'Richter-Magnitude'. mb: The body-wave magnitude mb is typically recorded for earthquakes that occurred more than about 2000 kilometers away from the recording station. It can be computed relatively fast, because its value relies on the amplitude of the so-called P-phase of an earthquake. P-phases are waves travelling through the body of the earth's interior and are the first signal that reaches a seismic station. For large earthquakes (magnitude larger than 6), mb 'saturates', meaning that even if the actual size of the earthquake is larger, the value of mb does not increase any more. In such cases, seismologists have to rely on other magnitude types. MS: The surface wave magnitude MS is measured from surface waves. These waves travel along the surface of the earth with a velocity much slower than P-waves travel through the earth. Therefore, one has to wait a longer time, until these waves arrive at a distant station and MS cannot be computed as rapidly as mb. Depending on distance, it may take up to 1 or 2 hours until surface waves arrive, compared to a maximum of 20 minutes of P-waves. MS is measured from 20 s period waves (compared to 1 s for mb) and 'saturation' begins only for very large (magnitude larger than 8) earthquakes. The slow surface wave speed is the reason, why seismologists cannot distinguish quickly between a strong and very strong (magnitude 6) earthquake. Earthquakes close to the earth's surface (say, the upper 30 kilometers) generate large surface waves compared to a same-size earthquake at larger depth (this has to do with how surface waves are generated). Shallow earthquakes are more prone to cause damage than deep ones; a high MS-value compared to the mb-magnitude thus indicates that strong damage might have occurred for an earthquake close to a major urban area. The ratio between MS- and mb-magnitude is also a good measure to distinguish earthquakes from (nuclear) explosions. Explosions have a much smaller source-volume than similar sized earthquakes and explosions typically cause less shearing motion (which mainly generate surface waves) than earthquakes. Explosion MS-values are thus typically much smaller than for an earthquake of the same size. For shallow seismic events, the mb/MS ratio is thus a good discriminant (large ratios pointing to an explosion). Mw: The moment magnitude Mw is the only magnitude that is directly related to the physics at the earthquake source. Mw is derived (based on theoretical considerations) from the seismic moment M0, which is the product of the fault area times average displacement at the fault times material rigidity. In theory, Mw does not saturate since M0 includes the complete earthquake rupture. Several ways exist to determine Mw; often Mw is obtained by fitting seismic waveforms or spectral amplitudes by scaling synthetic seismograms to match observed seismogram amplitudes. The procedures are (a bit) more time consuming than simple seismogram amplitude measurements (ML, mb, MS) and Mw for larger events globally are currently available several hours after an earthquake. M: Whenever the magnitude type in one of our lists is given as 'M', this means, that the seismological observatory reporting the specific magnitude did not specify how the magnitude was computed. Often, these are magnitude values from the NEIC. You may assume, that such a magnitude value represents 'their best effort', and for strong earthquakes such magnitudes often are magnitudes of the type Mw. http://www.seismo.ethz.ch/redpuma/magnitudes.html ******* What this all does not say is that the background noise is 5.5 M "whatevers" for negative North Pacific and Atlantic anomalies and for positive anomalies according to the height and depth of the sea level highs and lows, the likelihood for runs of greater than 6 M. increases with the contrast of air pressure systems at sea level. (I have no idea how upper air levels affect the convergence of sub soil acoustics. No doubt that which accompanies severe storms accompanies severe earthquakes.) ******* Some more background: MAP 5.1 2009/06/12 14:32:56 -17.355 167.637 35.9 Vanuatu MAP 4.1 2009/06/12 11:42:52 53.090 172.766 15.6 Near Islands MAP 6.0 2009/06/12 09:44:20 -17.611 167.748 52.6 Vanuatu MAP 5.0 2009/06/12 09:24:45 -17.540 167.677 53.6 Vanuatu MAP 5.0 2009/06/12 08:47:43 -17.491 167.650 53.2 Vanuatu Having removed everything below 4M. (blasted Alaskan 4.1!!!) we have 4 medium sized quakes showing up consecutively at one place. (OK, I'm hoping the Alaskan will be marked down, they usually drop a couple of magnitudes on closer inspection.) I haven't checked the Atlantic sea level charts but I have no doubt that there were a sequence of parallel occlusions accompanying one or two Lows predicted before the Vauatuans occurred. A pair indicates that the meteorological storms are ended. That is, there will be no more tornadoes; and three indicates that the storms extant are ended but that another is due to scale up. 4 of them, on the other hand, is something quite rare. And it is a pity that that bloody Aleutian took place when it did to muck things up. But there you go. Or not as the case may be. |
#12
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On Jun 12, 10:04*pm, terry tibbs wrote:
the idiot dawlish is back again spamming us with his crap gfs t+240 betting shop bugger off will you Fat chance. He has a psychosis. Just live with it. He has to. So do his workmates. Just be thankful he is not an United States of American. Imagine if he ran for presidunce. They'd all vote for him. Or if he joined their navy, promote him as vice admiral in charge of counting the spoons at Pearl Harbour's mess halls. Well someone has to do something there to cope with all the seamen. |
#13
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On Fri, 12 Jun 2009 15:22:48 -0700 (PDT), Weatherlawyer
wrote: On Jun 12, 8:35=A0pm, wrote: Keep it coming, Mr McNeil.....!! snip lots of erudite stuff But there you go. Or not as the case may be. You are a tease! I thought you might say that! Best wishes Geoff |
#14
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On Jun 12, 11:32*pm, wrote:
On Fri, 12 Jun 2009 15:22:48 -0700 (PDT), Weatherlawyer wrote: On Jun 12, 8:35=A0pm, wrote: Keep it coming, Mr McNeil.....!! snip lots of erudite stuff But there you go. Or not as the case may be. You are a tease! I thought you might say that! Best wishes Geoff You have a fan W! However, again, you've produced a whole load of retrospective stuff and your "explanations" are just links that you see - they aren't really there. It's your lack of capability to predict that brings into question everything about your theory. You can write long posts until the cows come home justifying your predictions, but the words just don't add up. Again, you've made a prediction about "strong" earthquakes around the Isthmus of Panama, mentioning nothing about Vanuatu in your analysis of this quarter "spell". Look back to the first post. You can't suddenly begin to justify earthquakes in the Vanuatu area, simply because they have happened and therefore there must have been a cause related to your theories. You guessed the wrong place for the earthquakes. You think your theories are correct, but the actual outcomes, in terms of predictions show clearly that they aren't. It's only when someone looks into these outcomes that your scribblings are revealed as what they really are. No prediction accuracy: no use. |
#15
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On Jun 12, 11:22*pm, Weatherlawyer wrote:
The background noise is 5.5 M "whatevers" for negative North Pacific and Atlantic anomalies combined. As there is a certain lack of convergence. So here is another set of permutations: A state where both oceans are negative, giving the above results. (Tornadoes.) One where the Atlantic is negative and the Pacific is positive (I think this indicates a surge of Hawaiian volcanic activity.) Another where the Pacific is negative and the Atlantic is positive. And one where both oceans are positive. (Lots of convergence above and below ground.) For positive anomalies: According to the height and depth of the sea level pressures, the likelihood for runs of greater than 6 M. increases with the contrast of air pressure systems at sea level. 5.1 * *2009/06/12 14:33 * * *17.4S. * * * * *167.6N. * * Vanuatu 6.0 * *2009/06/12 09:44 * * *17.6S. * * * * *167.7N. * * Vanuatu 5.0 * *2009/06/12 09:25 * * *17.5S. * * * * *167.7N. * * Vanuatu 5.0 * *2009/06/12 08:48 * * *17.5S. * * * * *167.7N. * * Vanuatu So this 6.0M. was pushing it. http://earthquake.usgs.gov/eqcenter/...uakes_all.html When we have 4 medium sized quakes showing up consecutively at almost the same location. It has the same effect as a much larger quake. The weather changes with very large quakes. Contemporary models and such come "right" (possibly needing less correction. I wish I could say.) I haven't checked the Atlantic sea level charts but I have no doubt that there were a sequence of parallel occlusions accompanying one or two Lows predicted before the Vauatuans occurred. Yep! But only one pair of parallels as far s I know. And that with a 997 mb Low just west of the UK. I have no doubt* that this Low was some 80 degrees from Vanuatu when the series occurred. But I have not checked my facts. I'd bet too that in another part of the ocean or in the N Pacific some 80 degrees from said series there is the other pair on file. There is one for midnight on this site: http://www.wetterzentrale.de/topkarten/fsfaxsem.html Zeigen for the 13th June A pair indicates that the meteorological storms are ended. That is, there will be no more tornadoes; and three indicates that the storms extant are ended but that another is due to scale up. 4 of them is something quite rare. Pity this set was flawed. But talking about convergence. They were some 5 or 6 minutes apart: *14:33 09:44 09:25 *08:48 If they had all arrived on time it would have been a very large quake. Contemporary theory has it that magnitudes don't add up in the same way I'd put them and I don't intend to find out what they consider the increase would be. It was on line once as that is where I read it. Anyone except Dawlish wishing to follow it up can do so at their leisure. I imagine Dawlish would eat his teeth before finding out anything, even if he knew how. But I am being unkind to an unfortunate. I should be more generous. He provides so much entertainment. I hope he doesn't hang himself in his desponderence one day, when he could be trained with so little effort. Do they have trains at Exitdoor? I'm sure they do. Let's hope the driver knows him. |
#16
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On Jun 13, 8:24*am, Weatherlawyer wrote:
On Jun 12, 11:22*pm, Weatherlawyer wrote: The background noise is 5.5 M "whatevers" for negative North Pacific and Atlantic anomalies combined. As there is a certain lack of convergence. So here is another set of permutations: A state where both oceans are negative, giving the above results. (Tornadoes.) One where the Atlantic is negative and the Pacific is positive (I think this indicates a surge of Hawaiian volcanic activity.) Another where the Pacific is negative and the Atlantic is positive. And one where both oceans are positive. (Lots of convergence above and below ground.) For positive anomalies: According to the height and depth of the sea level pressures, the likelihood for runs of greater than 6 M. increases with the contrast of air pressure systems at sea level. 5.1 * *2009/06/12 14:33 * * *17.4S. * * * * *167.6N.. * * Vanuatu 6.0 * *2009/06/12 09:44 * * *17.6S. * * * * *167.7N.. * * Vanuatu 5.0 * *2009/06/12 09:25 * * *17.5S. * * * * *167.7N.. * * Vanuatu 5.0 * *2009/06/12 08:48 * * *17.5S. * * * * *167.7N.. * * Vanuatu So this 6.0M. was pushing it. http://earthquake.usgs.gov/eqcenter/...uakes_all.html When we have 4 medium sized quakes showing up consecutively at almost the same location. It has the same effect as a much larger quake. The weather changes with very large quakes. Contemporary models and such come "right" (possibly needing less correction. I wish I could say.) I haven't checked the Atlantic sea level charts but I have no doubt that there were a sequence of parallel occlusions accompanying one or two Lows predicted before the Vauatuans occurred. Yep! But only one pair of parallels as far s I know. And that with a 997 mb Low just west of the UK. I have no doubt* that this Low was some 80 degrees from Vanuatu when the series occurred. But I have not checked my facts. I'd bet too that in another part of the ocean or in the N Pacific some 80 degrees from said series there is the other pair on file. There is one for midnight on this site: http://www.wetterzentrale.de/topkarten/fsfaxsem.html Zeigen for the 13th June A pair indicates that the meteorological storms are ended. That is, there will be no more tornadoes; and three indicates that the storms extant are ended but that another is due to scale up. 4 of them is something quite rare. Pity this set was flawed. But talking about convergence. They were some 5 or 6 minutes apart: *14:33 09:44 09:25 *08:48 If they had all arrived on time it would have been a very large quake. Contemporary theory has it that magnitudes don't add up in the same way I'd put them and I don't intend to find out what they consider the increase would be. It was on line once as that is where I read it. Anyone except Dawlish wishing to follow it up can do so at their leisure. I imagine Dawlish would eat his teeth before finding out anything, even if he knew how. But I am being unkind to an unfortunate. I should be more generous. He provides so much entertainment. I hope he doesn't hang himself in his desponderence one day, when he could be trained with so little effort. Do they have trains at Exitdoor? I'm sure they do. Let's hope the driver knows him. Oh W. All I ask is some confirmation through a few correct forecasts. If you do that, it will be worth looking into. Without that; why bother? The abuse shouldn't be necessary, though it is for you when you are questioned by anyone. It's your pattern. The phrase; "no forecast accuracy: no use", will continue to haunt you. Whenever anyone reads this stuff, just think of that. Until W really begins to anaylse the accuracy of his forecasts and shows some kind of statistical evidence that these constant (kind of) forecasts show a link between the moon, tectonics and weather, the stuff that is being presented for us is pure fantasy. Entertaining fantasy, perhaps, as your fan has said, but pure scientific fantasy. True, isn't it? |
#17
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On Jun 11, 8:00*am, Weatherlawyer wrote:
Rather long and old hat but bear with me: A phase at midday or midnight indicates a misty cool spell of clam weather with any winds coming from the north or east. I love clam weather with a scalloped sky, it warms the cockles of my heart especially when I can flex my mussels with a quick scampi down to the shops, or use my oyster card for a trip up west. I may even play chess outside if I can find enough prawns, but being a shellfish sod I do get very crabby when I lose. |
#18
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Every morning a minute pressure difference follows the sun. Presumably
there is one that follows the moon as it is a cold wave at 6 am and warm one at 9 am. Also presumably this wave occurs at noon and 6 and 9 pm. I don't know if it can be measured for all the other background changes but early in the days of admiralty log books providing the weather data that people like FitZroy tried to work with, a certain mid Atlantic island governor studied the phenomenon and deduced such a wave from statistical analysis. A small step from that is looking at the Atlantic chart every 6 hours and watching these small pressure waves build up. I don't pretend to know their cause but you really can see Low pressure regions develop as these things converge. This is what I mean when I use the term. I have no real idea what the more knowledgeable understand about it. Nor do I care over-much. Likewise when a series of waves sound waves reach a certain point under the earth where they can meet and reinforce other sets of waves arriving there from different directions, the peaks and troughs produced have a frequency of their own. Sometimes these are barely noticeable. Sometimes they peak as small tremors, sometimes as larger ones and sometimes as catastrophic earthquakes. And the weather changes. Permutations of these effects are tornadoes, volcanic eruptions and above cloud lightning. Too little is known and almost nothing is reported on the latter phenomenon to make conjugation with lunar phases possible. Since it IS possible to show a relationship between the other stuff (one only has only to look for a series of the right lunar phases running consecutively for that.) it is possible to work out what the weather should be doing when it palpably is not doing what it should. It doesn't take much experience to form the idea that a run of certain weather should bring a devastating phenomenon. Since these usually occur at the end of the run the time to watch out for them is towards the end of the last of the similar phases. Although the present run, now ending has been a wet spell or series of spells, the type of wet spells has differed one from the other. But we should still be able to see something interesting as the next phase takes hold on the earth. The 29th of June 2009, should be an interesting distraction as it breaks the spell temporarily: 29 JUNE 11:28 A spell of fine weather with ridges dominating part of the spell. 7 JULY 09:21 An unstable thundery spell of the sort that didn't produce much thunder IIRC from the 25th April. 15 JULY 09: 53 And this one is some 30 minutes different from the last which is quite a near miss for lunar phases which are seldom that obliging in producing matches. I think even smallbrain should be able to follow that, and I don't mean that in the way he usually runs up one's backside after every post. |
#19
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On Jun 13, 7:06*pm, Weatherlawyer wrote:
Every morning a minute pressure difference follows the sun. Presumably there is one that follows the moon as it is a cold wave at 6 am and warm one at 9 am. Also presumably this wave occurs at noon and 6 and 9 pm. I don't know if it can be measured for all the other background changes but early in the days of admiralty log books providing the weather data that people like FitZroy tried to work with, a certain mid Atlantic island governor studied the phenomenon and deduced such a wave from statistical analysis. A small step from that is looking at the Atlantic chart every 6 hours and watching these small pressure waves build up. I don't pretend to know their cause but you really can see Low pressure regions develop as these things converge. This is what I mean when I use the term. I have no real idea what the more knowledgeable understand about it. Nor do I care over-much. Likewise when a series of waves sound waves reach a certain point under the earth where they can meet and reinforce other sets of waves arriving there from different directions, the peaks and troughs produced have a frequency of their own. Sometimes these are barely noticeable. Sometimes they peak as small tremors, sometimes as larger ones and sometimes as catastrophic earthquakes. And the weather changes. Permutations of these effects are tornadoes, volcanic eruptions and above cloud lightning. Too little is known and almost nothing is reported on the latter phenomenon to make conjugation with lunar phases possible. Since it IS possible to show a relationship between the other stuff (one only has only to look for a series of the right lunar phases running consecutively for that.) it is possible to work out what the weather should be doing when it palpably is not doing what it should. It doesn't take much experience to form the idea that a run of certain weather should bring a devastating phenomenon. Since these usually occur at the end of the run the time to watch out for them is towards the end of the last of the similar phases. Although the present run, now ending has been a wet spell or series of spells, the type of wet spells has differed one from the other. But we should still be able to see something interesting as the next phase takes hold on the earth. The 29th of June 2009, should be an interesting distraction as it breaks the spell temporarily: 29 JUNE 11:28 A spell of fine weather with ridges dominating part of the spell. 7 JULY *09:21 An unstable thundery spell of the sort that didn't produce much thunder IIRC from the 25th April. 15 JULY 09: 53 And this one is some 30 minutes different from the last which is quite a near miss for lunar phases which are seldom that obliging in producing matches. I think even smallbrain should be able to follow that, and I don't mean that in the way he usually runs up one's backside after every post. But W. For the hundredth time. If all this works, why can't you use it to predict?? |
#20
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On Jun 13, 7:06*pm, Weatherlawyer wrote:
A small step from that is looking at the Atlantic chart every 6 hours and watching these small pressure waves build up. I don't pretend to know their cause but you really can see Low pressure regions develop as these things converge. This is what I mean when I use the term "convergance". I have no real idea what the more knowledgeable understand about it. This is what one source (RA-Aus) says about convergence, divergence and subsidence: Atmospheric vertical motion is found in cyclones and anticyclones, mainly caused by air mass convergence or divergence from horizontal motion. Meteorological convergence indicates retardation in air flow with increase in air mass in a given volume due to net three dimensional inflow. Meteorological divergence, or negative convergence, indicates acceleration with decrease in air mass. Convergence is the contraction and divergence is the spreading of a field of flow." http://www.auf.asn.au/meteorology/section1b.html I on the other hand am talking about an increase in the number of low pressure waves. As they arrive already in combinations that take the pressure to 990 to 980 millibars they already consist of a number of wavlets each worth about 2 or 3 millibars decrease in pressure. They converge off Iceland and Greenland as if waiting the full pressure capacity required to get them over the Mid Atlantic Ridge. This has to be some 970 or so minimum IIRC. When they hit land once more you can see them separating out into their constituent air masses. Blowing where they list. The article goes on to describe what happens without explaing why. It is difficult to see why an air mas floating free of any vessel has to build up or con~/di~ ~verge: "If, for example, the front end of moving air mass layer slows down, the air in the rear will catch up – converge" How? And more importantly; why? "The air must move vertically to avoid local compression. If the lower boundary of the moving air mass is at surface level all the vertical movement must be upward. If the moving air mass is just below the tropopause all the vertical movement will be downward because the tropopause inhibits vertical motion." How and why? "If the front end of a moving air mass layer speeds up then the flow diverges. If the air mass is at the surface then downward motion will occur above it to satisfy mass conservation principles, if the divergence is aloft then upward motion takes place. Rising air must diverge before it reaches the tropopause and sinking air must diverge before it reaches the surface. As the surface pressure is the weight per unit area of the overlaying column of air, and even though divergences in one part of the column are largely balanced by convergences in another, the slight change in mass content (thickness) of the over-riding air changes the pressure at the surface." |
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