BUT WHY

[Captain]

BUT WHY?

 

I have 3 questions for the learned members of the Forum:

 

BACKGROUND: There is a substantial weather event here this weekend and we have had strong winds overnight such that my dog got blown down to Gundagai, and today will be totally unflyable with strong winds predicted, the freezing level will be down from 12000 ft yesterday arvo to 4000 today and we have snow predicted on the mountains and blizzard conditions in the warnings.

 

QUESTIONS

 

1 Given all of the above, why did the wind still drop at dawn and dusk, same like it usually does?

 

2 It is an obvious and incontrevertable fact that conditions as I have described above only happen when a group have spent immeasurable effort on organising a Fly-In, as they have in Corryong and Mount Beauty this weekend. So what is the firm & causal link between Fly-Ins and crappy weather? (The link is so direct that there just has to be an optic fibre cable somewhere in the mix for this to be so definite?)

 

3 Why is it that when the Cockies crank up their Headers at harvest time, the clouds get greyer?

 

Please help.

 

Regards Geoff

 

 

[Guest pelorus32]

I have 3 questions for the learned members of the Forum:BACKGROUND: There is a substantial weather event here this weekend and we have had strong winds overnight such that my dog got blown down to Gundagai, and today will be totally unflyable with strong winds predicted, the freezing level will be down from 12000 ft yesterday arvo to 4000 today and we have snow predicted on the mountains and blizzard conditions in the warnings.

 

QUESTIONS

 

1 Given all of the above, why did the wind still drop at dawn and dusk, same like it usually does?

 

2 It is an obvious and incontrevertable fact that conditions as I have described above only happen when a group have spent immeasurable effort on organising a Fly-In, as they have in Corryong and Mount Beauty this weekend. So what is the firm & causal link between Fly-Ins and crappy weather? (The link is so direct that there just has to be an optic fibre cable somewhere in the mix for this to be so definite?)

 

3 Why is it that when the Cockies crank up their Headers at harvest time, the clouds get greyer?

 

Please help.

 

Regards Geoff

G'day Geoff,

 

I was interested in your question about dawn and dusk - couldn't decide whether it was an old wives' tale or not :big_grin:

 

But I found this little snippet that begins to explain it. Boils down to the fact that wind is a solar phenomenon.

 

BBC News | Eclipse99 | Rain or shine

 

As for the rest of it? <Insert shrug emoticon/>

 

Regards

 

Mike

 

 

[Guest palexxxx]

had strong winds overnight such that my dog got blown down to Gundagai, and today will be totally unflyable Please help.

Regards Geoff

Geoff,

 

What model dog do you have and how long have you been flying him. What is his range and can he take passengers?

 

 

[Captain]

What model dog do you have and how long have you been flying him. What is his range and can he take passengers?

G'day Paley. The dog is a lab/kelpie cross and I calculate her glide ratio to be about 6:1, with a heal biting ratio of just 2:1 when she gets really cross.

 

Mike. I understand that the wind is solar powered, but why does it drop for those couple of hours when the sun goes both ways over the horizon? It is not an old wives tail, as it appears to happen most days that it becomes calm(ish) around dawn and dusk ... (but not always).

 

Regards Geoff

 

 

[motzartmerv]

It all depends on if the butterflies in china flap thier wings or not..;)

 

caos theory..

 

 

[facthunter]

Wind at Dawn/Dusk.

 

The winds at height do not vary in velocity significantly during the day/night as they do near the ground. This is most to do with the MIXING of the airmass in the lower levels caused by the surface being heated by the sun during the day, resulting in changes to the adiabatic lapse rate, and generally more instability, (bumpiness).

 

At night, when this heating is not present, the air is calmer, and doesn't mix with the "freestream" wind so much.. Not all winds drop off at night. near high peaks you can get downflowing cold( and denser ) air, that can be quite strong, and will build up after sunset. I'm not going into the complex names for these phenomena, just the principles.. Nev.

 

 

[Yenn]

Was it cat or dog abatic you were referring to Nev? Maybe it was captains dog.

 

Not sure about the heal biting ratio. Is it the ratio of raw wounds to healed ones?

 

 

[motzartmerv]

Just to add a bit to Nevs post.. The sun is the engine that drives nearly all the weather we experiance on the ground, and indeed in higher levels of the atmosphere..

 

But it does this by convection, so, the air is heated not directly by the sun but rather, the ground is heated by radiation from the sun, that heated ground them warms the air in contact with it by convection... This is something that all these greenies that harp on about global warming fail to realise. The sun breathes and pulsates over time, there is an 11 year sunspot cycle that has much more of an effect on weather experianced on earth then the measley 1/2 a % of co2 found in the atmosphere..

 

Sorry to get off topic, but can anyone find me a single shred of scientific evidence that co2 is a greenhouse gas???

 

ahhh....soap box back in the corner...

 

 

[blueshed]

Hi Geoff

 

could it be "Farming is the Most Respected form of Gambling" ?

 

Hope the wind turns around and returns your Dog ! and did she shat on the "Tucker Box" while there?

 

Was meant to be goint to Tyabb this weekend myself, just checked the weather, lovely head wind and absolute charlie rap. Is it still pooy in Wagga?

 

Cheers Guy

 

 

[Captain]

Could it be "Farming is the Most Respected form of Gambling" ?Hope the wind turns around and returns your Dog ! and did she shat on the "Tucker Box" while there?

 

Was meant to be goint to Tyabb this weekend myself, just checked the weather, lovely head wind and absolute charlie rap. Is it still pooy in Wagga?

 

Cheers Guy

G'day Guy

 

Yesterday @ Wagga airport the Met recorded 26 knts gusting 42 and today it has abated all the way down to 24 gusting 34 from W/SW when I checked it just now .... and I understand that the mountains are white. So I hope none of our guys tried to get into the Mt Beauty or Corryong Fly-Ins yesterday. It would have been a bit interesting up there in those mountain valleys.

 

Have tied the dog to the shearing shed for safety and she has only dragged it a metre or so overnight once the chain had stretched. She looks a bit like one of those kite surfers, except the kite has legs.

 

Best regards Geoff

 

PS Re Motza's post #8, I don't know the scientific detail, but I do know that the science of "global warming" is not absolute, yet most greens portray it as so and the pathetic gutless (manage the country by press release) polys seem to accept it as so. We even have some whacko down here spending money on TV adverts urging the population to "Go Veg" so that there will be less demand for meat and less cattle pharting will decrease methane levels. One final point is that with the huge masses of people to our Nth in Indonesia, China and India I see little gain for the Aussie population to beat itself to a pulp, and raise its own costs, over issues like coal burning power stations when any improvement we make will mean bugger all in the overall scheme of things.

 

Ah ... I love the smell of AvGas in the mornings.

 

 

[Captain]

Does anyone east of Adelaide have gusts less than 30 knots today?

 

And did anyone fly today? If so .......... details please?

 

 

[motzartmerv]

I went out to the airfield (jaspers) thismorning.. I couldn't assertain the wind direction and strength because the windsock was ripped off the pole...not just the sock sail, but the steel rod and bearing was sheared... It was a bit of a hint that flying wasn't the best idea today..;)

 

 

[dunlopdangler]

Hi there geoff, In answer to your 3 questions, Firstly as the sun goes down the localised atmospheric activity will also decrease giving a less intense wind activity close to the ground (what motzartmerv said earlier). Out of ground effect the pressure gradiant winds will still be working as per the conditions...as for the other two questions, has to do with a bloke called Murphy and his law!!

 

 

[Yenn]

About global warming. A lot of people couldn't believe that an ibdrease of only a small percentage of CO2 could cause a big increase in temperature but experiments have been done which show that although we have always had CO2 in the atmosphere, there is a sudden, great increase in the blanketing effect for a very small percentage increase.

 

We have been having changes in World climate since the world began, but our activity has greatly changed the environment and even if it is not the sole cause of our problems, it would surely help to limit our excesses. Even better limit our population, before Mother Nature does it for us, with another flu epidemic or SARS, or maybe something even worse. Should we go back to the days of World Wars, or even all behave as they do in Africa and parts of Europe.

 

 

[Captain]

Hi there geoff, In answer to your 3 questions, Firstly as the sun goes down the localised atmospheric activity will also decrease giving a less intense wind activity close to the ground (what motzartmerv said earlier).

Yes .... but why does it usually drop just while the sun rises and falls .... then resume again an hour or 2 later?

 

What is so significant to our winds about the sun crossing the horizon in both directions, which appears to calm the wind for a couple of hours or sometimes less?

 

 

[Captain]

..... but our activity has greatly changed the environment and even if it is not the sole cause of our problems, it would surely help to limit our excesses. Even better limit our population, before Mother Nature does it for us, with another flu epidemic or SARS, or maybe something even worse. Should we go back to the days of World Wars, or even all behave as they do in Africa and parts of Europe.

Ian

 

That is laudable, but what is the point in OZ doing it when the bulk of the world population, which are relatively close to us, probably will not? I have worked in India and China and our population and emissions are insignificant in comparison.

 

And how do you propose that "our" population be "limited"? Are you speaking for the Skippys or the world as a whole?

 

Re your final sentence above, watch this space. If you think that those days are behind us you are kidding yourself. Our generation(s) have lived in a utopia for the past 60 years or so without a major world conflict and that, most likely, will not continue forever.

 

That is why we must fly and have fun as often as we can.

 

Regards Geoff

 

 

[turboplanner]

Question BUT WHY

 

Just to add a bit to Nevs post.. The sun is the engine that drives nearly all the weather we experiance on the ground, and indeed in higher levels of the atmosphere..But it does this by convection, so, the air is heated not directly by the sun but rather, the ground is heated by radiation from the sun, that heated ground them warms the air in contact with it by convection... This is something that all these greenies that harp on about global warming fail to realise. The sun breathes and pulsates over time, there is an 11 year sunspot cycle that has much more of an effect on weather experianced on earth then the measley 1/2 a % of co2 found in the atmosphere..

Sorry to get off topic, but can anyone find me a single shred of scientific evidence that co2 is a greenhouse gas???

 

Until the year 2000, there was some doubt, but following ice core drilling which enabled counting of isotopes over 600,000 years, global warming was proven beyond doubt. There has been a sharp increase since the Industrial Revolution began in the 19th century when CO2 production rapidly increased with the burning of fossil fuels, so it's due to (a) CO2, (b) punching time clocks © boredom with repetitive work.

 

Forget the greenies and media Merv, the place to get the news is from the Intergovernmental Panel on Climate Change which consist of level headed scientists who are becoming concerned with things like a piece of the West Antarctic ice shelf the size of the Bellarine Peninsula breaking off.

[motzartmerv]

Yes, i agree, there is little doubt that the atmosphere is heating up.. Now this is where the science gets iffy.. Are we the cause of this?/...well, i don't think we are.. In the psot WW2 years there was sudden economic boom which came on the back of massive amounts of industry.. In short, the world needed to rebuild and it did so .. Factory's and things sprung up all over the world..Now acording to the "global warming science" this should have been accompanied by an increase in temperature...but.... it wasn't..in fact the opposite occured..the temps started to fall..to the point where the world feared an ice age..

 

Also, if you want to talk about ice cores, why do we always forget about the ice cores drilled in the syberian desert.. these cores indicated that there has been times in our recent history ( last 500000 years) where co2 levels have been 3 times what they are now...Now we weren't around to be the cause of this one??

 

And what about the sattelite images of ice shelf's breaking up??...oh no.... pictures from space showing clear evidance we are doomed???..i think not...how long have we had birds in space?? capable of getting these shots??.....not long... for all we know this could be a common repative event, occuring over and over agin in recent mellinia....

 

The sea hold a lot of the worlds co2.. now the doomsdayers will tell you that as the co2 is released from the sea, the globe heats up...but clear evidence points to the fact that its actually the reverse thats happening...as the globe heats up, then the co2 is released...

 

So becarefull when spouting "science"...its easilly twistable into what they want you to think...

 

cheers

 

 

[Methusala]

The Earths atmosphere is a layer of gas almost unbelievably thin in comparison with the bulk of the planet. It is isolated from the vacuum of space by way of its mass. It collects heat mainly through convection by contact with the surface of the planet. Once it warms it has little chance to cool except through contact with the cold vacuum at the edge of space. The more energy into the system, the more convection. Call this convection weather. It is more helpful to use the term climate change to describe this increase in meteorology. It is quite irrational to believe as some apparently do that the huge amounts of energy released by the burning of hydrocarbon fuels in the increasingly industrialised world will not have an effect on the weather. I don't think that the use of "greenie" as a descriptor of those who trust the vast majority of scientific opinion in this area is helpful to rational arguement. Yours sincerely, Don

 

 

[facthunter]

Separate the discussion.

 

Might be better if the "global warming Skeptics" had their own space. If every discussion on meteorology is going to go to where we are at here, we will miss out on a lot of RELEVANT information being discussed about phenomenon that directly affect our flying environment. I am not suggesting that the topic is not important, but it is surely out of context here. Start a new thread IF you want to...Nev.

 

 

[turboplanner]

What confuses the debate is that people combine two time scales.

 

Over hundreds of thousands of years the world cycles between extreme heat/volcanic to ice ages, and we are currently cooling towards the next Ice Age in a few hundred thousdand years. This is not of immediate interest when buying property by the beach today, but what we do have is 600,000 years of irrefutable tempertature figures which include a very sharp spike beginning about the mid 1800's when the Industrial Revolution started, and its that spike the scientists are conecrned about.

 

 

[slartibartfast]

Guys, I have to agree with Nev.

 

There are other threads discussing global warming and our affect on the environment (or not), or you can start another one if you have something fresh to say.

 

Could you confine your posts to answering Captain's questions please? Especially question 3.

 

Cheers,

 

Ross

 

 

[Guest Graham Lea]

Question 3 is for someone as omniscent as a moderator to answer, we mortals have no idea - but are willing to accept a direction (other than that aready directed of course) :-)

 

 

[turboplanner]

Question 3 - It only happens to the nervous ones who hesitate, wait till they see the neighbour taking the crop off, and start the harvest on the back end of a High, or it may be that they strayed from the thread.

 

 

[Guest Ruprect]

Oil, Coal, Gas, Uranium - all finite resources. I don't care much for the scientific arguments for and against the proving/disproving of Global warming. If all this scare mongering gives alternative technology development a kick in the pants, then thats got to be a good thing. I don't expect to see much of a change in my lifetime, but I know I will see an electric car being quite common on city streets. I also expect to see electric recreational aircraft being a common site around airfields. The best thing about these two technologies being developed....The arabs not being able to hold the world to ransom and whinging residents near airfields not being able to complain about noise pollution. No don't bother telling me the current problems with these technologies, did Orville & Wilbur envisage a modern fighter jet?