The Great Airport Mystery

[christina p]

We have a scientific mystery I hope you'll help me solve, but one perhaps ensnared in the riddle of human nature.

First, let me briefly recap: In my previous post, "Astonished By Apparent Absence Of Snowfall Data" I basically presumed the existence in the UK of comprehensive snowfall data of the sort we routinely have in the US and Canada and asked, perhaps a bit petulantly, "Where is it?" Thanks to some excellent responses, especially a link supplied by Thundery Wintry Showers to the Met Office Anomaly and Actual charts, and Terminal Moraine's detailed, exhaustive description of the content of the old Snow Surveys of Great Britain, I think I can answer my question: "Nowhere!" Yes, I believe that the kind of records we have for every major and many minor cities in the US--exact monthly and seasonal snowfall amounts going back at least many decades, often more than a century; daily snowfall, if any, for the entire period (Did it snow, you randomly ask, on Valentine's Day in 1971 in New York City? Yes, as a matter of fact, 1.1 inches officially in Central Park, and it continued on the 15th where the city had another 2.3 inches.) and many more precisely measured snowfall indices--don't exist in a systematic way in Britain.

All indications are that the only official,systematic records that do exist re snow in the UK involve the depth of snow lying on the ground at 9 in the morning and the number of days on which snow fell in a given month. Both are only very roughly correlated with actual snowfall amounts and are thus laughably unsatisfactory. But why then collect this data and not the more sensible and desirable kinds? Well, here's where it gets interesting, and it is what prompted this new thread.

For the period from the late 18th century to say, 1950 or so, there's a ready explanation: time, effort, money, and most of all, an unwillingness to get out of a warm cozy bed in the middle of a bitter January night . To collect the kind of data we have in the US requires someone who will go to the site at any hour of the day or night, i.e. the moment the snow stops falling, so that the measurement will not be corrupted by melting, compacting, drifting, or being washed away by snow that's changed to rain. Further, during a storm, he must go to the site at midnight to make a measurement for the calendar day. I needn't point out how this differs from all other basic measurements--you had your "minimum" and "maximum" thermometers in the old days, and your ample rain gauge, so that you could visit the site once a day (say, when you're measuring the lying snow!), and have fully and with scientific precision discharged your data-collection responsibilities. Why Americans of that era in so many places were happy to shoulder the added burden of accurate snowfall measurement (or were well paid to do so!), while the Brits were not, is a matter for speculation.

But that brings us to The Great Airport Mystery. By 1950, maybe a little later in WWII-ravaged Britain, all major cities had round-the-clock airports, with a meteorological staff, wide-awake and on duty in the middle of the night. They were not just fully capable of doing the required measurements, but there was a vital necessity-- gathering information on the amount of snow accumulation and its rate of fall, for the safe operation of one's own airport and for the safety of airports yet to experience the storm, is probably more important than acquiring any other kind of information. And of course, the official temperature and rainfall data, for most cities, has been taken from its airport for 60 or 70 years at least. Just picture the situation: They're already doing other official measurements, it's easy to include snowfall measurement (just step outside), and, more important, it's absolutely essential, plus you have trained meteorologists right there LITERALLY 24/7/365 to do it, so....

But the data apparently doesn't exist. HOW IS THIS POSSIBLE? Somebody connected with, or knowledgeable about, weather observations at Heathrow, Gatwick, the airports of Manchester, Liverpool, Birmingham, Edinburgh, Glasgow, etc. at any time from the 1950's to the present please respond with some explanation, some solution to this genuinely perplexing mystery, or even just the tiniest hint of an inkling, because this absence of data defies logic, human nature, and the irresistible imperative a scientist feels to collect and preserve essential data in his field.

　

　

[Terminal Moraine]

It's an interesting question you raise, Christina. Why our American cousins should take it upon themselves to record hourly snowfall data when, as far as I'm aware, this has never been the case on this side of the Atlantic I have no idea.

Does it perhaps have something to do with a Teutonic attention to detail? Do our European neighbours also record hourly snowfall data? I can imagine it would be something the Germans, French, Swiss or Austrians would do and perhaps it the influence of their ancestors which has filtered through into the American meteorological psyche.

Even tiny centres of population in the USA give the population number and height above sea level on the 'town sign', something you never find in Britain. Why is this? I hypothesise it is the European influence, any comment?

Edited July 11, 2009 by Terminal Moraine

[chrisbell-nottheweatherman]

The altitude thing was something I wondered about recently. Why don't we do it?

[christina p]

Hello again, Terminal. You suggested that it might be America's inheritance of a European "attention to detail" that accounts for our precision in recording snowfall. I can only say that anyone in my country who's had any work done on their homes--say, the installation of a plumbing fixture, only to see it burst apart within a week, flooding the bathroom-- will be less convinced than you that Americans display an "attention to detail" as a national trait. (Sorry my compatriots, but I must be honest.) But militating even more strongly against your hypothesis is the fact (I think it's a fact, but in this arena everything is suspect) that all of Europe is exactly like the UK regarding snowfall data. Despite my searches, I can't even find the simplest, most basic information--annual snowfall-- for ANY European city! Even Oslo! At one site, amidst the wealth of temperature and rainfall data charts, it said simply that Oslo is "a snowy city". THANK YOU SO MUCH FOR THAT PRICELESS MORSEL!

And to me, what's remarkable (at least since 1950) is not that the US (and Canada) have collected the data, but that the rest of the world (apparently) has not. It's not OUR attention to detail, but THEIR obliviousness to crucially important data!

By the way, did you take the name Terminal Moraine solely because of its connection to the Ice Ages whose departure you (and I) lament so bitterly, or do you actually have terminal moraine near where you live? I know there is some in England, but I'm not sure of its location. Incidentally, a few days ago I said to a friend of mine--one who's often teasing me about my incessantly exhorting the weather gods to send NYC yet another blizzard, the more crippling the better-- that I'm not entirely alone in my madness. I told him there's a kindred spirit in England who's 'patiently awaiting the return of the Younger Dryas'. He laughed uproariously--once I explained what the Younger Dryas was! I think you and I are two of about eleven people on earth who want to fight global warming because it's delaying the next Ice Age! Oh, I wanted to mention that "NOVA", a science program on Public Television in the US, had a pretty decent show a few months ago on the latest evidence regarding the initiation of the Younger Dryas, called "Last Extinction" and you can watch it online at pbs.org/wgbh/nova/programs/ But I must warn you, the evidence for an unlikely-to-be-repeated-anytime-soon extraterrestrial impact event is compelling enough to force you to change your tagline to "Despairing of the return of the Younger Dryas".

[Terminal Moraine]

Morning Christina; very early morning I should think where you are.

Well that's another theory blown out of the water!

Could it be perhaps that the Pilgrim Fathers and their immediate antecedents were so overawed with the immensity of the USA and Canada and their grandiose climate/meteorology, that they decided, as they had a completely clean slate, that things would be done properly from the outset?

It's all to easy, if a recording precedent has been set, and particularly if it's been going for many years, to follow the lead and not take it upon oneself to delve into greater detail.

Perhaps the early fathers with their pioneering spirit were of the same ilk as people like Clement Wragge who took it upon himself to take daily readings at the summit of Ben Nevis, and at intervals on the slopes, over a period of several years. Anyone who has spent any time in the western Scottish Highlands in winter cannot fail to be in awe of his dedication and determination.

As there is already a precedent in your part of the world for recording hourly snowfall data the scientific community will want it to continue for as long as finances permit ( most things come down to finance in the end ) for there are few things more upsetting to a scientist, even an amateur, than abandoning detail. On the other hand it takes an iron resolve ( and the necessary financial commitment ) to make the jump from less detail to much more, when for many decades less detail has been the norm. For this reason it would take a cataclysmic altering of attitude on this side of the Atlantic to adopt the hourly recording regime that you enjoy.

With regard to my username, it is entirely related to my fascination with the last (and other) Ice Age(s) and episodes such as the Younger Dryas. As far as I'm aware the nearest terminal moraine to where I live is somewhere near York, a distance of about 90 miles; near by your standards but a fair distance in these islands.

Edited July 12, 2009 by Terminal Moraine

[christina p]

TERMINAL, YOU ARE A VERITABLE HYPOTHESIS-GENERATING DYNAMO!!!

I certainly agree with one point you made: once a tradition is established, people find it difficult to depart from it, no matter how misguided that tradition might be. Actually, it's even worse than that--it needn't even be a tradition. If a person in a position of authority issues a command (or, merely, quietly requests that something be done) the overwhelming majority of people will do it, even if the behavior requested is violative of every norm of decent, moral conduct. The famous Stanley Milgram/Yale University "Obedience to Authority" experiments in the 1960's demonstrated that in a stunning, nauseating way. I don't know how familiar those in the UK are with these utterly fascinating studies. Essentially (I'm greatly simplifying here), the subjects were (falsely) made to believe they were participating in a study of 'learning and negative reinforcement', and were instructed to give an escalating series of electric shocks to the 'learner' as he answered questions incorrectly or not at all. These shocks, according to the control panel in front of the subject, were labeled from mild to dangerous to XXX. Actually, no shocks were given, but the study was constructed so that the subjects completely believed they were in fact administering shocks, and a large majority of subjects continued to press the button to deliver the voltage, including XXX shocks and beyond, when they had good reason to believe the recipient was unconscious or dying!!!

So, I agree, whether a person in authority, or a tradition, instructs an individual to do something, generally he'll do it. (Not me, NOT ME!-- but perhaps I'm deluding myself. Nobody ever believes oneself a docile, pathetic marionette ludicrously dancing at the whim of the puppeteer and yet studies show most people, in the right circumstances, will be just that!)

And it's probably true that in Europe (including of course the UK) a tradition arose that a morning measurement of lying snow was all that was necessary; in the US, a different practice was established either because, as you put it "perhaps the Pilgrim Fathers and their immediate antecedents were so overawed with the immensity of the USA and Canada and their grandiose cimate/ meteorology that they decided, as they had a completely clean slate, that things would be done properly from the outset", or, simply, given the very limited dissemination of information in those days, they were just plain UNAWARE of what the European practice was. After all, the people emigrating to the New World would hardly have been spending their leisure time (as if they had any!) reading meteorological journals (as if there were any!!). So they just did what seemed logical to them, which was recording actual snowfall rather than morning lying snow.

But even a powerful tradition can be overwhelmed by the arrival of radically new circumstances, with overarching new priorities. And that's exactly what happened with the advent of aviation. Measurement of snowfall totals, and especially snowfall rates, was now something that had immediate, practical, life-saving value. No longer was this merely a data-collection enterprise for the "sake of improving mankind's knowledge". Whatever the European tradition HAD been, in order to have safe landings and take-offs, and to know whether to divert or cancel flights, you had to know the precise status of the snowstorm. Incidentally, Terminal, you've made several references to the hourly measurement of snowfall in the US, as though this has been the American way from the beginning. In fact, this was NEVER done until the measurement shifted to airports, and was specifically undertaken to determine the rate of snowfall for air safety reasons-- in those days of course there was no sophisticated Doppler radar to effectively establish rates. The official Central Park measurements in NYC (one of the few official stations NOT at an airport) does NOT do hourly snowfall measurement and never has--there's never been a need.

And that's the point of this thread. Given the absolute need to precisely determine snowfall rates, hourly measurement, or frequent measurement, was necessary. And once you have those hourly records, simple addition is all that is required to establish daily amounts, storm amounts, monthly totals, and seasonal accumulation. All this climate data should have flowed from the hourly snowfall rate measurements, and those measurements were indispensable to the safety of commercial aviation from its advent to at least the 1990's (when fairly reliable radar measurements of snowfall intensity could be made).

So then, did millions of people fly in Europe for 6 decades with their lives endangered because the airport meteorologists were content to just look out the window now and then instead of doing careful measurements of snowfall rates? Even though they were aware of what their colleagues in the US and Canada were doing? This is literally incredible to me; I really find it impossible to believe this situation could have been allowed. Or did they do the hourly measurements and then just discard them when the storm passed? That's even more unbelievable. That's why I so badly want input from people who have worked on, or know someone who worked on, an airport's meteorological staff, or from people who, by whatever means, know what has actually gone on in this domain during more than half an century. This is truly The Great Airport Mystery, and it must be solved!!! For heaven's sake, Where oh where is the meteorological Hercule Poirot, Miss Marple!? Rumpole! Disobey your wife, discover the truth and explain it all to us, the assembled, eager multitude!!!!!!

　

[Terminal Moraine]

But even a powerful tradition can be overwhelmed by the arrival of radically new circumstances, with overarching new priorities. And that's exactly what happened with the advent of aviation. Measurement of snowfall totals, and especially snowfall rates, was now something that had immediate, practical, life-saving value. No longer was this merely a data-collection enterprise for the "sake of improving mankind's knowledge". Whatever the European tradition HAD been, in order to have safe landings and take-offs, and to know whether to divert or cancel flights, you had to know the precise status of the snowstorm. Incidentally, Terminal, you've made several references to the hourly measurement of snowfall in the US, as though this has been the American way from the beginning. In fact, this was NEVER done until the measurement shifted to airports, and was specifically undertaken to determine the rate of snowfall for air safety reasons-- in those days of course there was no sophisticated Doppler radar to effectively establish rates. The official Central Park measurements in NYC (one of the few official stations NOT at an airport) does NOT do hourly snowfall measurement and never has--there's never been a need.

　

Ah! slight misunderstanding there. I should have referred back to your first post where you did make it clear that the hourly recording of snowfall was particular to airports, even very small ones.

We could do with the input of John Holmes here as I'm sure, in his days as a professional forecaster, he worked at several different airfields around Britain. Airfields certainly make hourly observations in this country but I am doubtful that they make hourly observations of snowfall, although I don't know for certain.

Perhaps it's down, ultimately, to the pitiful amount of snow we get over here in an average winter when compared to the USA or Canada, such that someone took the decision it wasn't worth recording on an hourly basis.

Oh how they must have regretted that decision ( if indeed there was one ) in a winter like 1947 or 1979.

With regard to Europe I have no explanation. There are cities/towns in northern Europe which must be comparably snowy with cities/town in the U.S ie Helsinki, Oslo, Munich, so who knows why they thought it unnecessary for their airfields to log every snow event.

I think John may be away on holiday at present, if he appears not to have seen this thread I'll p.m him.

[Coast]

The general reporting and archiving of snow at airports over many years must be recorded somewhere as they all produce METAR's and TAFs (typical for today at EGKK, Gatwick: weather.noaa.gov/weather/current/EGKK.html )

Here is a comprehensive analysis of what the short form information contained in METAR's and TAFs is: http://mbev.net/wikka/METARSandTAFS and here is a decoder for that info: http://www.skystef.be/metar-decoder.htm. You can see that part of that code includes references to snow and its condition. But I can't yet find anywhere, detailed records of depths at given hours for snowfall at UK airports.

I suspect (and John Holmes will confirm or otherwise) that there is only a general observation of snow and a forecaster attached to a base or airport is probably only required to use skill and experience as to how it would affect aircraft take-offs, landings and ground handling, not specific measurements.

One site I follow is the USAF (21st Operational Weather Squadron) based in Sembach, Germany and even they don't have published data online for historical snow depths, unless it's hidden behind the NATO sign in?

Edited July 13, 2009 by Coast

[J07]

I wonder if the Japanese do it? I think the snowiest city in the world (or one of the top few) is in Japan, is it not? Amusingly, at the same latitude as Auckland (where it hasn't snowed for 70 years...)

[Coast]

A bit of information has come to me which indicates that obs are taken at UK Airports and transmitted as NOTAMS that include snow depth data at half hourly intervals (when applicable).

However, like so many things, there is a cost to obtain this information and it doesn't appear to be made available to us the general public online or in any other format. So in conclusion, the data exists, what do you want to pay to receive it?!

Edited July 13, 2009 by Coast

[christina p]

Coast, thank you for your contribution from your intriguingly mysterious source. You express some nice cynicism when you say, "However like so many things, there is a cost to obtain this information and it doesn't appear to be made available to us the general public online or in any other format. So in conclusion, the data exists, what do you want to pay to receive it?"-- but Coast, I think you're not nearly cynical enough.

Let's analyze what your source is actually saying, in conjunction with some other, indisputable facts. First, your source says NOTAMS are sent that "include snow depth at half hourly intervals (when applicable)". The key phrase is "when applicable". In light of information I'll cite momentarily, "when applicable" almost certainly means nothing more than "during the most intense phase of a few snowstorms". This would comprise a meager few data points of no use to anybody and it certainly isn't something anyone would pay for! This is a far cry from systematic hourly readings during every snow event, as has occurred in the US and Canada since airports became official weather stations, or even just storm accumulation data for each snow event that would allow the compiling of monthly and annual totals! As proof that this latter has NOT been done historically in the UK, I cite Terminal Moraine's comprehensive listing of exactly what the annual Snow Surveys of Great Britain, published for decades until the 1990's, contained--there is absolutely no information on actual snowfall, only morning lying snow. (See my previous thread, "Astonished By Apparent Absence Of Snowfall Data", post #9, where Terminal Moraine recounts in exquisite detail the content of those Snow Surveys.) If there had been comprehensive half-hourly measurements, or even just storm totals for each event, the compilers of the Snow Surveys surely would have used the information to give us monthly and seasonal snowfall at the sites--it's obviously far more relevant and valuable than "morning lying snow" and there's no reason to keep it secret, for goodness sake! Especially if you are NOT simultaneously offering to make it available at a price, which they have in fact NEVER DONE. Clearly, comprehensive data--heck, even just your most basic piece of information, "average annual snowfall"--does not exist. NONE of the many researchers who have made their life's work the history of British weather have cited it, and THEY surely would have laid their hands on it if it existed.

Furthermore, this complete unavailability of snowfall data, including the simple "average annual snowfall", evidently is the case throughout Europe. Are we to believe that for 60 years all the varied governments of Europe, conservative and liberal, Communist and democratic, have compiled the snowfall data but conspired to keep it (alone among all weather data) a STATE SECRET?????!!!! Cue the "Twilight Zone" music!! No, Coast, all logic says that data doesn't exist. If your source says it does, all he needs to do is provide us with 60 years of monthly snow totals for all the major British airports (hey, I'll settle for just one airport) and I'll do a legendary grovel in apology. That's how science works; you don't CLAIM data exists, you PRESENT it.

But now I want to move on to my major point, a truly important one I believe. Apart from the reasons already discussed in this thread and my previous one regarding the need for precise snowfall measurement, there is another reason, one that far transcends those already mentioned, that I've delayed discussing because of some controversial conclusions that flow naturally from it.

Snowfall prediction is simultaneously the most difficult and the most important of a meteorologist's tasks. No regularly occurring weather event is more disruptive to people's lives, but none is harder to forecast accurately. Having observed the evolution of East Coast US storms practically since my infancy (my mother claims I cast my dolls aside and was busy measuring snow out in our backyard with a ruler at age three), I'm all too aware of the many factors that can cause a proclaimed "lurking monster" off Cape Hatteras to fail to explosively deepen as expected, or to be surprisingly starved of expected Gulf of Mexico or Atlantic moisture, or to turn out to sea, etc. or, contrarily, I've seen the occasions when the city was besieged with "ten inches of partly cloudy", as the public likes to joke.

No one would dispute that the essence of science is forming a hypothesis, making predictions of outcomes based on that hypothesis, and then seeing if the predictions are confirmed or proven false. Thus, as meteorologists in the 20th century sought to predict the course and magnitude of snowstorms, they formed hypotheses about the way a variety of factors would affect storm development, and made predictions of snowfall in various locations based on their hypotheses. THE CRUCIAL FINAL STEP, WITHOUT WHICH THERE IS NO SCIENCE, IS TO THEN GO OUT AND MEASURE THE ACTUAL SNOWFALL IN THOSE VARIOUS LOCATIONS, COMPARE IT TO YOUR PREDICTIONS, AND ACCEPT OR REJECT YOUR HYPOTHESIS! How else can you improve snowfall forecasts and advance the science of meteorology? In the US and Canada the meteorological community recognized the LITERALLY INDISPENSABLE requirement to measure actual snowfall, and they meticulously did so. In Europe they did not. (And it's even more desirable, though this is not NECESSARY, to make many interim measurements, such as hourly, during the storm. This would allow one to see exactly what portion of the hypothesis (in this context, the hypothesis was simply their forecast model) was faulty. For example, did they get the early stages of the storm just right, but then fail to account for its middle stage intensity?)

So, in the US and Canada, excellent measurements were made, and thanks to this feedback, forecast models changed and improved radically over the decades, as meteorologists saw their predictions regarding storms in the early years painfully fail to conform to the reality on the ground-- but then they modified those models, saw predictions improve, etc. But in Europe, where no such feedback from snowfall measurements was available, there could be no such progress. That is the burden of European meteorology-- a 50 year abandonment of the scientific method. Once measuring was made so easy, by having airports with round-the-clock meteorological staffs, to not have done so is completely inexplicable and frankly, inexcusable. Happily, in the US and Canada, scientists retained their sanity and provided the data that allowed the formulation of quite beautiful models (for everyone, here in the US and in Europe) that permit the superior prediction of snowstorms we have today (though decidedly far from perfect). And believe me, I say that without the slightest chauvinism-- I care not at all what countries are responsible for progress, only that progress be made. If the US had been as unscientific as Europe, it too would be the object of my ire, as it is whenever I think the US goes astray. And I'm not forgetting for an instant that Europe gave birth to Galileo and Newton, Maxwell and Einstein, Heisenberg, Schrodinger, and my personal favorite, Euler--though more a mathematician than a scientist, I can't omit the greatest pure intellect in history. So I am putting this European meteorological lapse in the context of otherwise brilliant science.

Finally, I'm reminded of a story told about the legendary violinist Jascha Heifetz and the virtuoso pianist Arthur Rubinstein. They attended a concert together one evening at Carnegie Hall by a seven-year-old piano prodigy who was performing some of the most difficult pieces in the repertoire. He displayed not just the most extraordinary technical ability, but showed, in his interpretation of the music, a sensitivity and insight unprecedented in one of his tender years. He was indeed a wunderkind! About midway through the performance, Rubinstein loosened his collar, complaining to Heifetz how uncomfortably hot the Hall was that night. "Not for violinists," Heifetz said.

I can easily imagine European meteorologists loosening their collars if the profoundly uncomfortable truth of their forsaking of the scientific method becomes clear to them.

[peterf]

thankyou for that,first long post i could read without squinting lol.

Edited July 14, 2009 by multi cellular thunderstorm
Removed the quote to save space

[Coast]

As I am not in a position (nor indeed do I want) to purchase the ability to have half hourly updates for snowfall depths and other data when it is snowing at airports in the UK, I cannot therefore publish historical or current details of that information. I have satisfied myself that the data exists and should an individual or commercial concern wish to purchase the information they can do so.

I also understand that as the information is primarily collected and produced for the safety of aircraft and passengers, that anyone else requiring it should pay for the privilege - it's not cost free after all. I have seen similar discussions about other information the Met Office chooses to release to the public for free and information they sell, as the commercial arm of a Government (MOD) organisation and I am happy with that as a taxpayer!

[Coast]

To illustrate what I understand, that snow depth is measured at airports but not necessarily released into the public domain, I researched a little more on t'interweb and on the CAA site found this:

1.4 Contaminated Runway Clearance and Reporting Runway State

1.4.1 Aerodrome operators are responsible for clearing contaminants from runways and manoeuvring areas and keeping them clear as far as is reasonably practicable. Aerodrome operators should also measure and report the depth and type of contaminant present. Conditions will be reported by SNOWTAM, OPMET, RUNWAY STATE MESSAGE or RTF on request.

1.4.2 Contaminant is measured every 300 metres, between 5 and 10 metres either side of the runway centre-line and away from the effects of rutting. The measurement is reported in millimetres as a mean for each third of the runway. The contaminant will be described as Ice, Dry Snow, Compacted Snow, Wet Snow, Slush or Standing Water.

www.caa.co.uk/docs/33/fod200619.pdf

[Coast]

SNOWTAMS! weatherfaqs.org.uk

METAR reports carry information relating to the state of ice/snow ON THE RUNWAY only, in a group properly called a 'runway state' report, but often referred to as a 'SNOWTAM'. The group should follow the TREND group. These groups have little relevance to general snow conditions in the vicinity of the airfield & care must be exercised when looking at these. The SNOWTAM (from the NOTAM - 'Notice to airmen' root) group takes the following format:

nnCLRDxx

nn: runway designator (50 added to indicate 'right' runways; 88=all runways; 99=repeat of previous report)

C: Type of deposit (0=clear/dry; 1=damp; 2=wet/puddles; 3=rime or frost covered; 4=dry snow; 5=wet snow; 6=slush; 7=ice; 8=compacted or rolled snow; 9=frozen ruts or ridges; /=type of deposit not reported)

L: Extent of runway contamination (1=10% or less; 2=11 to 25%; 5=26-50%; 9=51-100%; /=extent not reported)

RD: Depth of deposit (note: millimetres NOT cm) 00=less than 1mm; 01=1mm etc. through to 90=90mm; 91=not used; 92=10 cm; 93=15 cm .. then 5 cm steps to 97=35 cm; 98=40 cm or more; 99=runway(s) not operational due to snow or runway clearance. //=not measurable or not significant.

When the runway (nn=specific runway or 88=all runways) is/are declared operational, the group has the four letters "CLRD" within it, with the braking action xx encoded.

xx: Friction coefficient/braking action.

UK airports issuing them?

EGAA Belfast Aldergrove

EGAC Belfast/City

EGBB Birmingham

EGBE Coventry

EGCC Manchester

EGCN Doncaster Sheffield

EGFF Cardiff

EGGD Bristol

EGGP Liverpool

EGGW London Luton

EGHD Plymouth

EGHH Bournemouth

EGHI Southampton

EGJA Alderney

EGJB Guernsey

EGJJ Jersey

EGKB Biggin Hill

EGKK London Gatwick

EGLC London/City

EGLL London Heathrow

EGMC Southend

EGNH Blackpool

EGNJ Humberside

EGNM Leeds Bradford

EGNS Isle of Man

EGNT Newcastle

EGNV Durham Tees Valley

EGNX East Midlands

EGPA Kirkwall

EGPB Sumburgh

EGPC Wick

EGPD Aberdeen/Dyce

EGPE Inverness

EGPF Glasgow

EGPH Edinburgh

EGPK Prestwick

EGPL Benbecula

EGPO Stornoway

EGSC Cambridge

EGSH Norwich

EGSS London Stansted

EGTE Exeter

EGTK Oxford/Kidlington

and if you really can't sleep:

GUIDANCE FOR THE DISTRIBUTION AND COMPLETION OF SNOWTAM FORM courtesy of NATS Limited, UK Aeronautical Information Service

[Coast]

So in answer to Christina's statement/question:

They're already doing other official measurements, it's easy to include snowfall measurement (just step outside), and, more important, it's absolutely essential, plus you have trained meteorologists right there LITERALLY 24/7/365 to do it, so.... But the data apparently doesn't exist. HOW IS THIS POSSIBLE?

They do take the measurements, but they don't make that information (even historically) available to the general public for free, why should they? It looks like its only available for day to day operational safety.

Your query should therefore, be one related to freedom of information or what can you get without paying for it?!

[Thundery wintry showers]

It sounds similar to the issue we have with model outputs. I mostly think of US copyright laws as being very stringent, but on providing weather information they are very much at the other extreme, and so many outputs from the American GFS model are freely provided to the public. In contrast the UK Met Office is state-owned and quite protective of its copyrights so we get rather less from the UKMO model. Other state-owned weather organisations across the globe such as the NZ Metservice are similarly protective.

Snow data may well be required to be made freely available in the USA due to the same laws, which do not apply in the UK especially with regards state-owned enterprises.

They do take the measurements, but they don't make that information (even historically) available to the general public for free, why should they? It looks like its only available for day to day operational safety.

There are plenty of reasons for making some things freely available- as a general rule, the more stringent the copyright, the less people get for what they buy, the greater the tendency is for people to do without rather than paying more, and correspondingly, the less exposure the products get. If people are making do with less and companies aren't getting any more money, everybody loses out.

On the other hand I think some element of copyright is necessary in order to ensure that people have to pay for some things- if everything's free then you have to find other ways of making revenue which can often be very difficult. In essence it's a balancing act. In recent years the UK Met Office seems to have moved towards providing more of its stuff for free (take the UK long-term average maps, HadCET etc. for example) which I see as a good thing.

My question to Christina here would be, what would be your use for hourly snow data? It will cost a lot less if it's non-commercial than if it's commercial.

[christina p]

Coast, you say "They do take the measurements, but they don't make that information (even historically) available to the general public for free". I won't repeat my arguments, I won't again offer my evidence, read my previous posts for that--but I contend they do not, and have not, systematically taken the measurements. It's not a question of being free or charging for it. A chart of monthly and seasonal snowfall over the past 60 years at the UK 's airports DOES NOT EXIST, I strongly believe. If you can show me the place to go where I, or an "official researcher", could pay X pounds sterling and procure it, you will have proved me wrong. I challenge you to do so.

Thundery wintry showers, a pleasure to see you again! You ask what my use would be for hourly snow data?

I PERSONALLY couldn't use a vast compendium of such data (though during a big storm here in NYC they often give reports from the 3 local airports of hourly snowfall to quantify the intensity, and I HAVE delayed auto journeys when I've heard the rate is 3-4 inches an hour!! Yes, that's actually occurred during some portion of each of the three monster storms we've gotten in NYC since 1996), but it would be invaluable to meteorologists trying to improve the prediction of snowfall.

Maybe in southern England predicting amounts is not important, but in snowier climes, in the UK, in Europe generally, and certainly here in the northeast US, accurate prediction of amounts is essential. It snows constantly here and few people alter plans just because it's going to snow. Everything is contingent upon the amount. And anything that will enhance the forecaster's ability to get those amounts right will be of inestimable value to the public, and also to city officials, for obvious reasons.

Actual hourly amounts and actual storm totals matched against forecast models' PREDICTIONS of hourly amounts and storm totals provide feedback vital for improving forecasts. That's how science works--my last post was devoted to zealously making that point. It's, to me, a huge embarrassment and totally unfathomable that researchers in Europe have been hampered (disabled, really) in their efforts to improve their snowfall predictions in the last 60 years by the absence of measured snowfall to confirm or prove false their models' predictions. What the heck did these researchers do to check their models' predictions, call their Aunt Sally in Stratford, and their old college buddy Jim in Glasgow and 20 other people all over the UK every time it snowed (sometimes in the middle of the night!), telling them to quickly (quick before it melts!!) go to their backyards and measure the depth and call back?

I still haven't gotten an answer to this issue, The Great Airport Mystery. Why didn't the meteorological community utilize this incredible resource (ALREADY IN PLACE FOR AVIATION-SAFETY REASONS!) of round-the-clock meteorological staffing at airports to at least get storm totals, if not hourly data, to provide this feedback for researchers. It's a scientific scandal that they didn't, in my opinion, but more than that, it's completely incomprehensible. That's why I'm seeking an answer. None has been offered so far that makes sense to me. Thundery, you clearly are an intelligent person, what is the reason in your opinion? I'm too curious to rest until I have an answer.

　

peterf says "Thank you for that, first long post i could read without squinting.", a reference to the font size I've chosen. That's precisely the reason I chose it!

But Peter's comment gives me a chance to remark on an interesting event that happened in this forum. A friend of mine who's been following my posts told me a few days ago that someone unleashed a furious diatribe against me (by the time I got a chance to look, it was gone; whether My Denouncer had misgivings or the moderator intervened I can't say) which apparently was based largely on my having used a font size different from the norm in this forum! My Denouncer, by my friend's account, was vicious and threatening in demanding that I immediately adopt a sensible type size or....

Fascinating-- as Mr. Spock often said in situations where he was confronted with especially outlandish human behavior. I suspect it was not just the DIFFERENT font size, but the fact that it was LARGER than the custom that so perturbed My Denouncer. Just who did I think I was, better than others, more important?

Actually, I selected it because a tiny font size makes sense only if there are space limitations, as in a newspaper. Question for My Denouncer: Are you aware that cyberspace is as boundless as the universe? Therefore, the only logical consideration is comfort in reading. Request to My Denouncer: Go to your bookshelf and select 5 books at random. Do any of them have a font size as small as that used on this forum? Of course not, because that's far too small to be comfortable for many people.

But what's of interest to me is a larger issue: Conformity. Did you notice by the way that peterf, who praised me for the larger font size I used, himself used the tiny size that's the custom here (go look!). Even though he preferred the larger, he didn't have the courage to violate the norm! Terminal Moraine and I were discussing this in another context in posts #5 and #6, above. (Hey Terminal, how are you? I felt bad when I saw you refer to the snow amounts in England as 'pitiful'. For an Ice-Age-Lover like you to have to endure that is a crime against nature! You should try to arrange to spend some January and February in Boston, a great city where the winters NEVER disappoint!)

Terminal made the point about how difficult it is for people to violate a precedent or tradition and I expanded it to a more general docility or passivity that characterizes most people. They just go along, whether they approve of what is happening or not. It's illustrated in this very forum not just by the font-size conformity but by the passivity of visitors. If you compare the number of views to the number of posts (and this is true not just at netweather but at all forums on the internet) the ratio is often greater than 100 to 1. (Analogously, I've heard radio call-in show hosts comment that fewer than 1% of listeners ever even dial the number.) Is it having nothing to say, or perhaps not wanting to make the effort, that makes people not post in forums? Possibly those reasons sometimes apply, but I suspect something else is afoot. Surveys have shown that people's greatest fear is not snakes, or heights or dying of cancer, but public speaking. And posting is, at root, similar to public speaking. And it's one part of this phenomenon I've just been talking about, essentially people being afraid to act 'conspicuously', whether in defying a silly font-size custom, or in posting in a forum and bringing attention, possibly negative attention, to themselves. I feel a little like that girl in what's considered the best commercial ever made, which aired only once, during the SuperBowl 25 years ago. Google it, search with the terms "1984 Apple ad", and watch it--it'll send chills down your spine! But I'm trying to rouse you, yeah YOU!, the person reading THIS word, out of your passivity. You're almost certainly an intelligent person with something to say. Why not say it? We'd all like to hear it! And if some wouldn't like to, and object to what you say, the heck with them!

[Thundery wintry showers]

With regards font size I'm afraid I find the traditional smaller font easier to read- some traditions are indeed there just for tradition's sake (in which cases I generally resent their enforcement) but others are there for good reasons.

My guess is that the UK has not been as interested in providing hourly snow data because snow is less common- a bit like TM said, and could have backfired in winters like 1947 and 1979.

[chionomaniac]

Christina, you make the point that you may delay a journey if snow is forecast to fall at a rate of 3-4 inches an hour. However in this country if we get 3-4 cm in a day the whole place grinds to a halt. We don't get snowfall that regularly, or heavlly to need to make these accurate readings. Believe you me if we get an inch or two of snow most people will remember it for years to come because it is so noteworthy and anything more the whole country shuts down and it's major news for a week. Look at the start of February, there will be enough recordings, maybe not official, of the snowfall that will probably last in the archives and memories forever.

Regarding your font size, as a reader I feel that when we don't know you or anything about you, that some people may feel that it is an aggressive way to put your point across even if you do not intend that to be the case. To me it is a little bit like that I am talking to some one who stands a little bit too close and invades my personal space when everyone else is far enough away to make me feel comfortable.

c

[Coast]

I still haven't gotten an answer to this issue, The Great Airport Mystery. Why didn't the meteorological community utilize this incredible resource (ALREADY IN PLACE FOR AVIATION-SAFETY REASONS!) of round-the-clock meteorological staffing at airports to at least get storm totals

Because we don't get enough snow to warrant the Government publishing specific hourly data (on the very odd occasions it does snow) in the public domain.

I suspect it was not just the DIFFERENT font size, but the fact that it was LARGER than the custom that so perturbed My Denouncer.

Well of course, everything is bigger in the States!!!

[christina p]

chionomaniac (or should I say, "fellow chionomaniac"), you comment that the amount of snow in England is too small to be concerned with precise snowfall forecasts: An interesting case can be made that just the opposite is true! Consider: In NYC, once the predicted depth exceeds 12 inches or so, NYC public schools are closed and many people don't go to work or they otherwise cancel their plans. So, suppose the forecaster predicts 6 inches and is off by 100%, and we get 12 inches-- then people are stranded who otherwise wouldn't be, fury ensues, etc. But still, the forecaster has wide latitude to be wrong- 6 inches. But in England, from what you say, if it's half an inch, or an inch, people soldier on, but at two inches, the world stops. Thus, if the forecasters predict an inch but are off by 100% and you get two-- then people are stranded who otherwise wouldn't be, fury ensues, etc. But now the forecaster's margin for error is only ONE INCH! Hence the need for greater, not lesser precision in British snowfall predictions!

chionomaniac, you say, regarding possible reaction to my font size choice:

"some people may feel that it is an aggressive way to put your point across... To me it is a little bit like that I am talking to some one who stands a little bit too close and invades my personal space"

That makes me feel a little (JUST A LITTLE!) like that not-very-well-behaved girl in the original Chris Isaak music video, "Baby Did A Bad, Bad Thing"--Unfortunately that video's been removed from YouTube, over the usual copyright issues. But maybe, in this one case, it's actually FORTUNATE it has been, because I fear if some netweatherites, impelled by curiosity, had checked it out, it might have proved just a wee bit (okay, WAY!) too racy for the delicate constitutions of some of the forum's older members. I wouldn't in any way want to have been responsible for increasing the mortality rate among weather-lovers.

Hey, Thundery! You say,"My guess is that the UK has not been as interested in providing hourly snow data because snow is less common". I really had intended my question to be about Europe, not just the UK, since all available evidence says the two had the same policy--no data collection of snowfall, whether hourly or by snow event. Why did the meteorological community throughout Europe fail to adopt the US policy once its airports had round-the-clock meteorological staffs, since it would have enabled rapid advances in snowfall forecasting for the whole of Europe, including the snowy northern portions, as I argued at length in my last two posts (and so I won't repeat it here)? Without such data, snow forecast models cannot be verified or falsified and thereby improved. STAGNATION!

Coast says, teasingly, about my font size, "Well of course, everything is bigger in the States!!!" (With a smile.)

You know, Coast, here in the States, we have that same attitude towards Texas. I understand there was a New Yorker who went down to Texas, to visit an old army buddy he hadn't seen in years, Big Joe. Big Joe had done very, very well since their army days and he wasn't shy about showing it. He picked up the New Yorker at the airport in his custom car, which was long enough to have had to factor in the earth's curvature in its design. As the New Yorker gaped in awe, Joe just smiled and said, "Everything's bigger in Texas, pardner." They entered Joe's house through a cathedral door- St. Patrick's Cathedral!! Joe's children's swing set-- Little Joe was 100 feet in the air when the New Yorker had to look away, from fear. And so it went, the rest of the day. Unfortunately for the New Yorker, the drinks were served in tumblers that conformed to the "Everything's bigger in Texas, pardner" motto, and he foolishly downed three of them. Later that night, when everyone had gone to bed, he was feeling very drunk and very dizzy, so he went out for a breath of fresh air. Unsteady on his feet, he walked in the pitch dark over the vast and unfamiliar grounds--suddenly, he slipped and fell into the pool. Struggling desperately but unsuccessfully in his drunken state to climb out, he frantically screamed at the top of his lungs, "Don't flush! Don't flush!!"

[Phil UK]

chionomaniac (or should I say, "fellow chionomaniac"), you comment that the amount of snow in England is too small to be concerned with precise snowfall forecasts: An interesting case can be made that just the opposite is true! Consider: In NYC, once the predicted depth exceeds 12 inches or so, NYC public schools are closed and many people don't go to work or they otherwise cancel their plans. So, suppose the forecaster predicts 6 inches and is off by 100%, and we get 12 inches-- then people are stranded who otherwise wouldn't be, fury ensues, etc.

That is true, but I'm guessing that even in NYC, snow can be fickle. Get too little when the weather forecaster says "x inches predicted", then disappointment. On the other hand, get too much when x inches were predicted and find yourself snowed in then anger and fury as you rightly say.

But in England, from what you say, if it's half an inch, or an inch, people soldier on, but at two inches, the world stops. Thus, if the forecasters predict an inch but are off by 100% and you get two-- then people are stranded who otherwise wouldn't be, fury ensues, etc. But now the forecaster's margin for error is only ONE INCH! Hence the need for greater, not lesser precision in British snowfall predictions!

Believe me, you should see how London in particular ground to a halt in early February of this year. Ok, the snow and its intensity was unexpected but I guess people would have set out for work as per normal if not slightly delayed BUT!! London transport in its infinite wisdom thought otherwise and took off most if not all of the buses, trains (Underground included) running at a skeleton service, schools closed, businesses shut...

I wouldn't have minded so much but it's not as if London hasn't ever seen snow before. I guess in NYC you lot can cope far better with it than we can. (And probably ever will! :huh: )

Phil.

Edited July 15, 2009 by Phil UK

[Roger J Smith]

They don't measure snowfall because they lost the rulers. :lol:

[BLAST FROM THE PAST]

HOPEFULLY THEY D RULERS IN MACROMETRES FOR THE UK

BFTP

Edited July 16, 2009 by BLAST FROM THE PAST