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Weather cycles: Place your pet theories here!

Discussion in 'Alpine & Southern' started by Falls expat, May 12, 2005.

  1. Falls expat

    Falls expat One of Us

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    Ok the mini debate in the Nosey thread got me thinking about all my pet theories.

    I have always sensed or believed that there are significant re-occuring weather cycles.

    I have a theory which has developed more based on other planets weather systems than ours. I have looked at beautiful pictures and movies of Jupiter and wondered how the horizontal weather bands or wind bands remain so distinct or separate. My conclusion which will probably not come as some great surprise is that Jupiter is a gas giant and we only see the outer most extent of the visible atmosphere. If as some might suggest there is a solid core of Jupiter, its irrelevant in many ways because the weather or turbulence we see is far removed from and surface interaction. Hence my theory is that the atmospheric systems are able to reach and semi-permanent equilibrium state according to its speed of rotation which maintains a seemingly static and perhaps predicible weather system.

    If we take this scenario to our planet we only have to look at the quasi-biennial oscillation

    to realise that in the upper atmosphere of Earth there exists a fairly predictable and regular wind pattern. This exist in part I believe to is isolation from turbulence from the earths surface.

    As we move further down towards the surface regular wave patterns or cycles become increasingly obscured by the influence of surface turbulence.

    However, this influence is in varing degrees. If you look at the upper tropospheric patterns at say 500-300hpa (5500-9200m aprox) in the southern hemisphere around the poles they exhibit a certain amount of regularity. It is these patterns that Frog uses with some success and therefore they can be used for longer term forecasting.

    Example of southern hemisphere circulation pattern at 500hpa.
    [​IMG]

    However, these same upper level patterns are less regular and therefore useful in the northern hemisphere. This I think is fairly uniformly accepted as being due to continental disruption. Example of northern hemisphere 500hpa circulation:
    [​IMG]

    Also the fact that the southern hemisphere has a land mass near as damn it central over the south pole and surrounded by sea at mid-latitudes is a good set up for setting up a fairly regular and uniform flow (e.g. at the surface the roaring forties).

    So in the southern hemisphere we are blessed in a way by having seemingly more regular weather patterns than the north, but alas the price we pay is very few observations. I am sure all of you that have been to the central or east coast states of America will love how the weather stations will tell you its going to rain, snow or be sunny the next day and 9/10 times it does. This is because the weather you are about to get has been observed and measured imediately upstream in the next state the day before. So in a way, apart from the uncertainty in developing systems, its hard to get it too wrong. (very simplistic view of course)

    So where am I going with this? Good question and I am not sure, but I hope discussion will ensue.

    I believe that there are many different significant wave patterns that are all out of sync most of time, but on occasions many of them become phased locked to give great or poor snow seasons or perhaps on the shorter scale a week or two of good snow producing storms.

    If we start listing them, we might start with Long wave troughs ignoring the fact why they are there for now but just consider them an existing buckling of the circumpolar flow.

    lets add short wave troughs which ride around the roller coaster of the long wave troughs which can enhance them or even destroy them or at least modify them.

    Throw in things like oscillations in the sea surface temperatures that travel around the circumpolar current. Tropical sea temperatures in particular the current El Nino state. The Madden Jullian oscillation. The annual movement of the intertropical convergence zone and subsets of this such as the Indian Monsoon, its onset and strength. All of these display wave like tendencies. They all have a wavelength and frequency.

    Anyway I have waffled on enough. If it were possible to identify the fundamental wavelengths of these systems it may be possible to tell when they move into or out of phase with each other and this I believe will be a fairly significant step towards longer term forecasting.

    [​IMG]
     
    #1 Falls expat, May 12, 2005
    Last edited by a moderator: Nov 14, 2013
  2. Falls expat

    Falls expat One of Us

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    Articles like this abstract are interesting on this topic as well from Here

    On the signal of the 11-year sunspot cycle in the stratosphere over the Antarctic and its modulation by the Quasi-Biennial Oscillation (QBO)
    Author: Karin Labitzke

    Source: Meteorologische Zeitschrift, 1 July 2004, vol. 13, no. 4, pp. 263-270(8)

    Publisher: E. Schweizerbart Science Publishers





    Abstract:

    In earlier studies it was shown that during northern winters as well as northern summers the QBO must be introduced to identify a solar signal. A clear solar signal emerges only when the data are stratified according to the different phases of the QBO. This signal is often of opposite sign in the respective phases of the QBO. During the easterly phase of the QBO the height differences between solar maxima and minima imply an intensification of the polar vortex (positive Annular Mode) throughout the year during solar maxima: During the northern winter half-year positive height differences (anomalies) are observed from about 90° S to 60° N, with negative anomalies further north; and during the southern winter half-year positive anomalies exist from 90° N to 45° S, with negative anomalies further south. The structure of the anomalies is very symmetric with a change between hemispheres in May/June and October/November. The consistently positive height and temperature anomalies during solar maxima/easterly phase over the tropics and subtropics imply anomalous downwelling, i.e.a weakening of the Brewer-Dobson circulation throughout the year – during solar maxima. The antarctic polar vortex and the connected Final Warmings are influenced by the 11-year solar cycle in much the same way as the arctic polar vortex. During solar maxima/westerly phase the midwinter warmings over the Arctic and the Final Warmings over the Antarctic lead to the negative mode of the Annular Mode (weaker polar vortex). They influence the whole stratosphere with downwelling (adiabatic warming) over the polar regions and connected upwelling (adiabatic cooling) outside the respective polar regions, reaching far into the other (summer) hemisphere. This leads to an intensification of the Brewer-Dobson circulation – during solar maxima.
     
    #2 Falls expat, May 12, 2005
    Last edited by a moderator: Dec 26, 2013
  3. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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    Sun cycles
    I have tried to look at solar cycles without too much success.
    There is the 11 years sunspot cycle when the sun emits about 0.1% more radiated energy. There also seem to be cycles of 21, about 180 years and 1500 years, but I’d need to look at my notes to give and accurate figure. Why look at such large periods?? If ALL of the sun's cycles correspond in a single years (or cluster of years), then this could have an effect on snowfall. e.g. maybe they trigger El Nino, etc.

    There is also something called the Maunder minimum which is characterised by a total lack of sunspots over an extended period of time, when the sun has a decrease of about 0.25% in radiated enrgy. The last was around the 1600's and corresponded to a period called the Little Ice Age, when the temperatures were low, and for example the Thames River in England froze every winter.
    [​IMG]
    I'm not sure if they've categorised how often this cycle occurs.

    Also related to solar radiation on the Earth are the “Precession of the Equinox†and the Earth’s elliptical orbit. The Earth’s axis is inclined by 23degrees, which causes summer/winter cycles…. If there was no tilt we would not have these seasons. However the earth has a “wobble†on its axis, and these seasons shift, doing a full cycle every 22,000 years, and is called the “Precession of the Equinoxâ€. Currently the Earth travels further from the sun every July due to the elliptical orbit. However, this closest approach varies according to the “Precession of the Equinoxâ€. The warmth in the northern hemisphere peaks every 22,000 years as the northern summer coincides with the closest approach to sun due to the eliptical orbit, and the minimum occurs 11,000 years later.
    These maxima & minima correspond directly to concentrations of CO2 and Methane in the atmosphere, because there is a much larger land mass in the northern hemisphere than the sounthern. We are currently in a downswing to a minimum.

    There is also the 95,000 year Milankovitch Cycle, a 95,000 year cycle in which the earth's orbit around the sun changes from a thin ellipse (oval) to a circle and back again. When the orbit around the sun is most elliptical, there is as much as a 30% difference in the distance between the earth and sun at perihelion and aphelion.
     
    #3 Sandy, May 12, 2005
    Last edited by a moderator: Nov 11, 2013
  4. Bugski

    Bugski A Local

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    Thanks Sandy. I'd never even heard of the last cycle you spoke of. Curious to know how on earth and orbit can cycle between elipical and circular and back again. Sounds very weird.
     
  5. churchy

    churchy One of Us

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    the SH animations are most interesting if you join a bunch of them together for a time period of over a month (greater than 27 days, actually).

    you see the same basic patterns pop in and out, strengthen and weaken but they never really disappear they just change.
     
  6. Nostradamus

    Nostradamus First Runs

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    I can't believe my eyes, after all these years 'respected' forum members are actually talking openly about their belief in "Weather Cycles" This is a real departure from the CHAOS theory where weather is Totally Unpredictable and non cyclic.
    Finally some light appears at the end of the dark tunnel of knowledge.
    Still think it was just a ploy to get me to post so some can have a 'bit of fun' at my expense, we will see.
    Sandy that Maunder Min has to coincide with other climate cycles to cause a "little ice age" as the world experienced in 1600.I Don't think the next one will happen in our life times by my estimates, actually quite the opposite in about 15 yrs.
    Sorry bad news for snow resorts, but if the weather cycles hold to past patterns then this will certainly happen.
    The closest approach of earth to the sun every year is called 'Perihelion' which occurs in the first week in Jan(generally Jan 2) varies slightly year to year.
    ’Aphelion’, occurs where the Earth is furthest from the Sun (around 2 July). Scientist generally believe that this does not affect our weather, which I don’t agree with, my personal opinion only.
    With a little concerted research as posted above by other ‘respected’ members we can soon realize that weather follows a very specific pattern, that is a given. However the really interesting question is what ‘drives’ these cycles like clock work. I would like to hear theories from others, I have already advanced my “ Heretical scientific†ideas else where, Time to Fess up yes Frog time to stump up your Methodology
     
  7. churchy

    churchy One of Us

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    i can't see how the elliptical orbit couldn't effect our weather. I mean it's a change in the amount of energy being injected into the the system so i think it must have some effect. it would be much harder to get and sustain a stable "steady state" system with a consantly changing energy input over such a long period.

    that said, when looked at from perspective where the period of the change of energy input is significantly smaller a steady state model could be observed.

    problem is that the periods of these things seem far too long to ever observe and process meaningfully during 1 lifetime.
     
  8. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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    I've talked myself about cycles before, and your post is very slightly antagonistic, which it doesn't really need to be. I would much prefer you to share your methodology as you have done, rather than have a "model" which has no substantive reasoning. Even if I don't agree with your reasoning, you have a right to post it and it promotes discussion, which is what I'm interested in.

    There is no ploy... Falls Expat was genuinely interested in explaining his own cycles theory (which we have seen before), being prompted by the idea of your current discussion about cycles. You read too much into it. It's close to the snow season, and if anyone deliberately has a 'bit of fun' at your expense, I will moderate it accordingly. I am on your side.

    I personally don't agree with this reasoning.
    A Maunder Minimum corresponds to a lack of Solar output of 0.25%, which is significant enough to effect temperatures world wide. Any other terrestrial cycles should not cause a little ice age not to happen.
     
    #8 Sandy, May 12, 2005
    Last edited by a moderator: Nov 25, 2013
  9. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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    BTW, When I mentioned the 22,000 year cycle, I mentioned that these maxima & minima also correspond directly to concentrations of CO2 and Methane in the atmosphere, which are currently in a downswing to a minimum, starting about 10,000 years ago.

    However, we will not reach these minima. The levels of CO2 started climbing again about 8,000 years ago, and Methane about 5,000 years ago.
    What this really means is that we should probably have ALREADY moved into an Ice Age......
     
  10. Nostradamus

    Nostradamus First Runs

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    Sandy Fair enough , my comments were not meant to be 'antagonistic' toward you or Falls or anyone else for that matter, sorry if you took it that way.
    Just a bit of 'tounge in cheek'humor about being being got at, no offence intended.
    It will be interesting to see what posts this thread stimulates from both the for and against points of view regarding weather cycles.
     
  11. Nostradamus

    Nostradamus First Runs

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    Sandy are you saying that the co2 and methane levels are the primary indicator for your belief that by proability we are over due for an ice age or is it a combination with low sun spot activity?
     
  12. Sandy

    Sandy Dark Sith Lord of the Pool Room Moderator Ski Pass: Gold

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    The Precession of the equinox follows a 22,000 year cycle. The CO2 and Methane levels follow the increase in solar radiation levels in the northern hemisphere. CO2 levels also follow cyclic shifts in the axial tilt (41,000 years).

    The CO2 levels dropped from about 265ppm 11,000 years ago, by now due to this cycle, they should have been down to 240ppm. However, 8,000 ago after dropping to 260ppm, they started rising again to about 280ppm now.

    The methane levels dropped from about 730ppm 11,000 years ago, by now due to this cycle, they should have been down below 500ppm. However, 5,000 ago after dropping to under 600ppm, they started rising again to about 720ppm now.

    Ice ages tend to be bottom out at about 200ppm for CO2 and about 480ppm for methane.
    If we assume that slightly higher levels of CO2 & Methane take us towards an Ice Age, then values of 240ppm for CO2 and about 500ppm for methane should have us going into an ice age.

    Any sunspot effects would be swamped by such a decrease in solar radiation.

    To summarise:

    CO2
    Max. 265ppm (warming trend)
    Min. 200ppm (Ice Age)
    today. 280ppm
    today. 240ppm (projected value according to normal cycle)

    Methane
    Max. 730ppm (warming trend)
    Min. 480ppm (Ice Age)
    today. 720ppm
    today. 500ppm (projected value according to normal cycle)
     
    #12 Sandy, May 12, 2005
    Last edited by a moderator: Nov 17, 2013
  13. woggybot

    woggybot One of Us

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    During an Aussie winter, a High, ANY High, will always beat a promising impending L into a useless position.... [​IMG]
     
    #13 woggybot, May 12, 2005
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  14. Snowies

    Snowies One of Us

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    I beleive in weather 'cycles' but it's almost impossible to quantify them in terms of snowfall over a ski season.

    I think this thread is moving into a Meteorology vs Climatology type discussion.

    Meteorolgy concentrates on the day to day forecasting - looking at the short term cycles which will have greatest effect on the weather that occurs tommorow and the subsquent 3 or 4 days.

    Climatology expands out to seasonal, yearly etc cycles that influence the short term cycles to arrive at long term forecasts that account for the day to day variations within a given period.

    Of course if everyone knew in advance what type of season we were going to have through the use of climatology then the discussion would move towards when will conditions be best during the season with a shift toward meteorology. I can't see anyone here providing a satisfactory solution to all aspects of ski season forecasting even if there are some interesting theories.

    In my time on this forum (I think this will be my 6th winter!!) I still see both the long term (year to year, month to month) and short term (day to day, week to week) type threads all wanting to know about how much snow and when, just the time frame differs.

    Looking at the current long wave situation, the system with the most promise in the Southern Hemisphere atm passed under Tasmania yesterday as it has a strong cold air fetch stretching back to the Antarctic coast and was a well developed amplication in the long wave pattern. This will probably peak in intensity in the next day or two and then over the course of the next week a system over South America will take that mantle.

    The large low that has everone so excited to the west of WA will continue to gather strength until early next week but will weaken and head south before it ever arrives as the high over southern Australia will also gather strength in the next few days making any potential changes in weather impossible. (but it sure looks impressive as it peaks, 540 line as far north as Brisbane)
     
  15. Falls expat

    Falls expat One of Us

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    I look at it as follows.

    If we assumed an idealised map separating polar air from tropical air i.e. the polar front theory.

    [​IMG]

    Then we take the average or normal zones of enhanced tropical convection this produces semi-permanent zones of high pressure due to decending tropical air (black arrows). Remember this is still ignoring many factors such as SSTs etc).

    [​IMG]

    We can see that the regular spaced location of the continents and oceans leads to potentially a fairly regular buckling of the tropical/polar thermal boundary (polar front).

    What happens if we upset this system by adding El Nino where SSTs over the tropical central and east pacific would lead to enhanced decent and buckling in a different location:

    [​IMG]

    This ignores huge amounts of other factors but I tried to give an impression how the polar frontal boundary may be changed by and El Nino.


    Here is another view of how a La Nina may affect the polar front.

    [​IMG]

    This kind of scratches the surface a bit, but what I was trying to get at is, what if there were other wave like patterns (e.g. Madden Jullian oscillation) that also altered this picture? You may well get a cancelling out process or an enhancement process?

    What happens if all wave patterns are weak or in between phases?

    I think there must be a way of making patterns emerge by process of elimination or perhaps the opposite.

    Sorry about my poor graphic skills.

    [​IMG]
     
    #15 Falls expat, May 12, 2005
    Last edited by a moderator: Nov 11, 2013
  16. quro

    quro First Runs

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    falls

    yup - you are close to the money as far as i'm concerned. i couldnt have said it better myself....
     
  17. quro

    quro First Runs

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    "We are working together to one end, some with knowledge and design, and others without knowing what they do."

    Marcus Aurelius
     
    #17 quro, May 14, 2005
    Last edited by a moderator: Dec 26, 2013
  18. quro

    quro First Runs

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    ....Yep you are right... This year perth has already had 98.8mm of rain since May 1st... This means it only needs 4.3mm in the remaining 15 days of May to reach the average.

    ...incidentally the record may rainfall for perth is 229.0mm - keep an eye on this years daily May obs for perth here
    Perth Climate Averages

    ...why a wet may this year??? i would guess it's probably mainly due to...

    1. The zonal(east-west) movement of areas of subsidence due to excess of air at height. These areas of subsidence stem from upper outflows closer to the equator. These areas move on time scales which range from weekly to seasonal.... falls recently mentioned this type of feature as being 'semi permanent'...
    Obviously if such an area of excess air is persistently sitting near perth in apr/may then the winter rains are likely to be later...

    2. The chance of well-timed frontal systems that happen to peak at WA longitudes, and how far north up the WA coast these systems go.... Obviously Cape Leuwin will start getting its winter rain before geraldton, on average, for just this reason...

    ...not nessecarily.... In fact if the frontal systems are reaching full maturity at perth longitudes, there is a good chance that they will be somewhat 'spent' by the time they reach vic...


    As a starting point, these are the monthly averaged SLP values over WA and the Indian Ocean, for Jan, Feb and March this year:
    <img src="http://users.bigpond.com/peter_luffman/weather/snow/movingWASubsidence.JPG" width="766" height="199">

    ...looking at the jan and feb charts, notice how the persistent area of descending air is initially sitting about 2000-3000km west of perth??

    ...in the feb chart, you can see this region of higher pressures start to squeeze itself eastward and make a peanut shape extending towards the bight, but with the area of strongest subsidence still well west of perth...

    ...moving into march, you can see the area of highest pressure is now in the bight. This set up is more conducive to allowing frontal systems to peak somewhere west of the bight.

    If you look at the march 2005 perth daily obs you will notice perth had only 6mm of rain for the first 27 days of march 2005- but on march 28th a 37.6mm fall was recorded... This was followed up a week later with 25mm falling in the first two days of april...

    The rest of april was mostly dry in perth as the subtropical ridge moved north, passing over the city..


    #This is a plot of the SLP and rainfall for Perth from Jan 1 2005 to yesterday.

    [​IMG]

    ...The 15 day running average pressure curve is drawn to give an idea of the movement of these areas of subsidence over a 2-4 week time-scale... This curve clearly shows a periodicity of these features in the order of 20-35 days. Notice how this 15 day pressure curve has a definite dip in late March-early April???

    Do you see how this agrees with the march chart above, where you can see perth is in the 'gap' between the 2 areas of general subsidence?? In fact about 75mm of rain fell in this short period of only 7 days.

    .....Falls has broadly described similar phenomena as 'areas of semi-permanent high pressure'. We can clearly see that in the perth 2005 example, 'semi permanent' means something of periodicity of c.20-35 days.


    Conclusions / Summing Up
    .....Falls has broadly described similar phenomena as 'semi-permanent areas of high pressure'. We can clearly see that in the perth 2005 example, 'semi permanent' means a periodicity in the order of 20-35 days.

    falls further talked about the various potential harmonics between different weather oscillations or motions --- in this particular case, snow_crazy has raised an example where the 12-month period changing of the seasons has interacted with the 30-day period movement of semi-permanent areas of high pressure. the result for WA has been a wet may, and an early sowing of the winter grain crop.
     
    #18 quro, May 16, 2005
    Last edited by a moderator: Nov 25, 2013
  19. quro

    quro First Runs

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    Falls

    Re: the above post, it's a composite of 3 or 4 posts i made in another thread. It actually relates more to this thread though so i pasted it in.

    If i find more posts in other threads here on the weather forum which fit in the category 'pet theories' or similar, i'll try to paste it into this thread too, and we'll end up with a nice concentrated thread with very little b/s...
     
  20. Falls expat

    Falls expat One of Us

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    Excellent post quro.

    Note the periodicy of your MSLP 25-30 days. Madden Jullian Oscillation (MJO) period is officially 30-60 days, but in reality its most commonly close to 30-40 days. Link? possibly, but of more importance is that if you have Low pressure at the Equator associated with MJO and Low pressure at mid-latitudes due to MSLP periodicy then this could well act to enhance the long wave trough. This will lead to colder air moving further north than average and warmer moving further south than average. It is also likely to lead to rainfall and temperature extremes.

    Interesting thought.
    [​IMG]
     
    #20 Falls expat, May 16, 2005
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  21. Monkey

    Monkey First Runs

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    Good post Quro.
     
  22. adminvb

    adminvb First Runs

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    Good thread. I prefer looking at SST's as everybody knows but have realised that the effects seen here in London (March snow in London caused by a localised effect of the Thames) and the lake efect in the states do not really apply to Australia.

    But I haven't given up on it completely. I'm still very interested in the effects of the polar currents in both hemispheres and beleive they greatly affect our weather - more in a moderating role to take the edge off. Recent news that the the 'chimneys' of cold sinking water near Greenland losing strength by as much as 40% is interesting. It will have an effect by slowing surface currents and a cooling of surface sea water. This means colder but dryer air in winter for Oz.

    Is it cyclical? Dunno, I don't think it is within our lifetimes anyway. It's more tied to the GHG and GW debates. I think that any consideration of cyclical weather should also take into account these large scale physical changes on our planet. What went before may not neccesarily happen again.
     
  23. Jacko000

    Jacko000 First Runs

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    Ill have a go, based on some very basic understanding.......

    The overall effect of elnino and/or global warming, has brought on slightly higher temperatures across the eastern district of Australia, particularly seen in recent weather observations.

    Going back to the water cycle, studied in yr10 i think, water evaporated from the sea rises, due to the heat caused by the sun, and accumulates in clouds. These then travel inland, and once they hit a large landmass, such as a mountain, the moisture cannot increase altitude and is released. If the air temp is cold enough, this precipitation will fall as snow. (snow them melts into streams and makes its way back to the ocean, then around once again).

    Therefore, this small increase in temp will create relatively much more evaporation, due to the large area of any water mass from which water can be evaporated, resulting in ‘heavier’ clouds. These will then travel over the Alps and release their contained water. As the temperature increase is only gradual, the air temp around the mountains will still be cold enough to produce snow, resulting in relatively large amounts of snow falling. As a result, I will be cruising through untracked powder on a more regular basis.

    I thought up this theory last year during the huge season we had, so hopefully this trend will continue through the next few years. So I am predicting a CRACKER OF A SEASON, at least I hope.
     
  24. adminvb

    adminvb First Runs

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    Another interesting find... A 2 decade cycle in the oceans around our area? This would have a massive influence on any moist air feeding in over WA.

    http://earthobservatory.nasa.gov/Study/WarmPool/
    A little more on my previous post
    http://www.nasa.gov/centers/goddard/news/topstory/2004/0415gyre.html
     
    #24 adminvb, Jun 22, 2005
    Last edited: Nov 25, 2013
  25. Falls expat

    Falls expat One of Us

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    Interesting stuff there Filski.

    Here are some more graphs and info from that site.

    A graph of the oscillation over time:
    The graph to the left shows the percent change in size of the West Pacific/Indian Ocean Warm Pool over time. The data were filtered to show the long-term fluctuations, a period of 9 to 12 years. (Graph courtesy Vikram Mehta, NASA GSFC)



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    This is the effect on global rainfall on a large warm pool maximum
    The Warm Pool affects the climate, particularly rainfall, around the world. During the months of June, July, and August, a large Warm Pool results in up to 25 percent lower than normal rainfall in Australia and South America, while a smaller than normal Warm Pool is correlated with an increase in rainfall in Australia, the Pacific Northwest, and the Mediterranean. The maps to the left show rainfall while the Warm Pool was large (top) and small (bottom), based on data acquired from 1908 to the present. (Images courtesy Vikram Mehta, NASA GSFC)


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    #25 Falls expat, Jun 22, 2005
    Last edited by a moderator: Dec 26, 2013
  26. adminvb

    adminvb First Runs

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    That's interesting... I had a bit of a quick look at snow depths and there doesn't seem to be a relationship between our season and the top graph. It's just another small piece in the puzzle.

    I'm more interested about how much attention is paid to climate change in the UK. It goes through all levels of the media and Blair pushes it strongly as well. I don't know if they expect a serious threat or not. One thing I did notice was the height of the Thames one day. There was less than a metre to the pavement level and boat wash was causing problems already. The Barrier is in place to cope with that to some extent but serious flooding could be a possibility in London during a storm surge at the wrong time.
     
  27. POW_hungry

    POW_hungry Part of the Furniture Ski Pass: Gold

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    Was there any reasoning for the height at the time, Filski?
     
    #27 POW_hungry, Mar 29, 2007
    Last edited by a moderator: Nov 17, 2013