The Severn has a tidal resonance like Fundy, doesn't it?
Cheers
Phil Hobbs
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Lake Eyre covers 3668 square miles that are below sea level, down to 49' (15m) below. It fills occasionally, when it has similar salinity to the ocean.
The basin from which it fills covers 463,323 square miles, nearly twice as big as Texas, or 70% the size of Alaska.
There have been sporadic proposals to dig a canal to the ocean to keep it full, to support local flora and fauna - but I foresee big problems with it becoming increasingly salty. 340km is a long canal to dig...
Clifford Heath.
I visited one of the old windmills, and calculated its power output at somewhere around 20kW. Quite a big structure, but probably not very efficient. Its job was to lift water less than 10m into a drainage canal.
The ocean doesn't need to be resonant. Super high tides occur at the "corners" of any ocean - like slop in the corner of a square bucket or pool. The Severn feeds that tidal slop into a shock-line that sharpens the pulse until it breaks - as happens in a few dozen places elsewhere in the world.
Tides in the Buccaneer Archipelego (north-western Australia, opposite Indonesia) regularly exceed 10m - slosh from the Indian ocean. There's no funnel leading to a tidal bore there AFAIK. The biggest one is in China.
If it wasn't for these effects, tides would be exactly equal around the world; about 1m following the moon adding to 0.5m following the sun.
CH
Why would anyone think it was important to destroy the native environment o f a given area??? The local flora and fauna have been living there for how long? Bringing in water would most likely upset the environment and chang e it irrevocably. Or is "local flora and fauna" a euphemism for the local citizens and their favorite watering holes?
-- Rick C. + Get 1,000 miles of free Supercharging + Tesla referral code - https://ts.la/richard11209
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of a given area??? The local flora and fauna have been living there for h ow long? Bringing in water would most likely upset the environment and cha nge it irrevocably. Or is "local flora and fauna" a euphemism for the loca l citizens and their favorite watering holes?
Lake Eyre does fill up from time to time, and there's a lot more local flor a and fauna around when it is close to full.
Digging the canal wouldn't "destroy" the local environment - just stabilise it at the wet end of the range.
-- Bill Sloman, Sydney
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nt of a given area??? The local flora and fauna have been living there for how long? Bringing in water would most likely upset the environment and c hange it irrevocably. Or is "local flora and fauna" a euphemism for the lo cal citizens and their favorite watering holes?
ora and fauna around when it is close to full.
se it at the wet end of the range.
That is incredibly naive. The local wildlife is adapted to those changes a nd lives best in those conditions. The dessert has plants that only bloom after a rare rain storm. If they would do better in a wetter clime, why wo uld they only live in the dessert?
It's not nice to fool Mother Nature.
-- Rick C. -- Get 1,000 miles of free Supercharging -- Tesla referral code - https://ts.la/richard11209
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.ment of a given area??? The local flora and fauna have been living there f or how long? Bringing in water would most likely upset the environment and change it irrevocably. Or is "local flora and fauna" a euphemism for the local citizens and their favorite watering holes?
flora and fauna around when it is close to full.
lise it at the wet end of the range.
and lives best in those conditions.
That is incredibly silly. The local wildlife has always been adapting to we tter and drier conditions. There's not a lot of it when Lake Eyre has dried out completely - even the organisms best adapted to living with very littl e water don't do very well then - but it recovers when there's more water a bout.
ould do better in a wetter clime, why would they only live in the desert?
You only see them in the desert. When they bloom elsewhere, lots of other p lants are blooming at the same time.
And Lake Eyre isn't exactly famous for it's wild flowers.
You can't fool Mother Nature - she's rhetorical trope, not an information p rocessing device.
-- Bill Sloman, Sydney
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onment of a given area??? The local flora and fauna have been living there for how long? Bringing in water would most likely upset the environment a nd change it irrevocably. Or is "local flora and fauna" a euphemism for th e local citizens and their favorite watering holes?
l flora and fauna around when it is close to full.
bilise it at the wet end of the range.
es and lives best in those conditions.
wetter and drier conditions. There's not a lot of it when Lake Eyre has dri ed out completely - even the organisms best adapted to living with very lit tle water don't do very well then - but it recovers when there's more water about.
would do better in a wetter clime, why would they only live in the desert?
plants are blooming at the same time.
processing device.
I'm not going to debate a topic you seem to be willfully ignorant of. Ther e are many places on earth where there are unique species specifically adap ted to the unique climate of that area. Those species often can't survive elsewhere either because they depend on something that is only found in tha t unique climate or they can't compete with other species that are better s uited to the other climates but unlike the other species they can survive i n the unique climate.
The alternating wet/dry conditions are exactly that sort of local climate t hat often has species specifically adapted to it and changing that climate would no longer allow those species to survive.
I'm sure you are aware of this. It sounds like something that is right up your alley and you can learn from watching any of a number of nature progra ms. I have no idea why you want to dispute the idea.
I also don't care. I made this final effort to be as clear as possible. C ontinue without me.
By the way, the Mojave desert is also not known for its wild flower, yet th e Mojave aster only grows there and the other similar areas of the south we st US. Not at all in wet climes.
-- Rick C. -+ Get 1,000 miles of free Supercharging -+ Tesla referral code - https://ts.la/richard11209
Pumping-out, though, beats letting it evaporate and collect dissolved impurities.
Parts of the old Salton Sea are heavily polluted (selenium, I hear) because no outpumping is done; over-irrigation sucks the impurities back into the groundwater. The rice fields in Texas contain a fair amount of arsenic, the better rice now comes from California. I'm thinking outpumping can be put to good uses in agricultural states. And, it gives you a use for episodes of excess wind-power.
If you don't have an outlet, it ends up like the Dead Sea.
It has a tidal bore like Fundy; Fundy is the only higher one I believe.
I'm not aware of any resonance effects. The bore is created by the overall funnel shape. It is noticeably higher with westerly winds an low pressure.
The other local phenomenon is that Southampton gets
4 high/low tides a day, as the water goes up the English Channel and around both sides of the Isle of Wight.
The Severn Estuary is funnel-shaped (think of it as an acoustic horn). As the tide travels up it, the "hydraulic impedance" (height/volume) increases, so the height of the tide increases.
The Severn becomes very tortuous as it get narrower, so the energy is dissipated in an ever-increasing terminating impedance and there is very little reflection, so resonance is minimal.
If it weren't for the losses, the estuary would form a very effective hydraulic transformer, converting the large-volume low tidal height range into a smaller-volume large height range, which would be more suited to a small but highly efficient electricity-generating barrage scheme further upstream. The previous proposals have all been for gigantic structures across the mouth of the estuary and huge turbines for large volumes of water with a low head.
-- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk
Yes. Pretty much - there are even some original picturesque pump houses with big steam beam engines that are now museums. Some areas have been rewilded as fens providing habitat for Bitterns and other rare birds.
Most of it is very fertile and given over to growing grain.
-- Regards, Martin Brown
I used to enjoy wandering around Stretham Old Engine, peering into the boilers and avoiding falling through the gaps in the floor. I doubt that is possible now,
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ironment of a given area??? The local flora and fauna have been living the re for how long? Bringing in water would most likely upset the environment and change it irrevocably. Or is "local flora and fauna" a euphemism for the local citizens and their favorite watering holes?
cal flora and fauna around when it is close to full.
tabilise it at the wet end of the range.
nges and lives best in those conditions.
o wetter and drier conditions. There's not a lot of it when Lake Eyre has d ried out completely - even the organisms best adapted to living with very l ittle water don't do very well then - but it recovers when there's more wat er about.
ey would do better in a wetter clime, why would they only live in the deser t?
er plants are blooming at the same time.
on processing device.
ere are many places on earth where there are unique species specifically ad apted to the unique climate of that area.
And you think that Lake Eyre is one of them?
something that is only found in that unique climate or they can't compete with other species that are better suited to the other climates but unlike the other species they can survive in the unique climate.
that often has species specifically adapted to it and changing that climat e would no longer allow those species to survive.
Lake Eyre doesn't do alternation, or anything as neatly regular as that.
p your alley and you can learn from watching any of a number of nature prog rams. I have no idea why you want to dispute the idea.
Because you seeing Lake Eyre as one more place that a nature program would feature. It's not that kind of place.
rred in 1886?1887, 1889?1890, 1916?1917, 1950, 1955 , 1974?1977,[13] and 1999?2001,[14] with the highest flood of 6 m (20 ft) in 1974."
Continue without me.
the Mojave aster only grows there and the other similar areas of the south west US. Not at all in wet climes.
So what.
-- Bill Sloman, Sydney
Fair enough. I live down hill from ~100 acres of farm land. I mostly think about diverting the run-off to keep some part 'dry'. But it doesn't really do that much... the soil is mostly clays, and if you dig a hole anywhere*.. it fills up with water in no time.
George H.
*well except for a couple of 'sand hills' that I think are left over from the last glacier.
Was Chebyshev from Southampton? ;)
Cheers
Phil Hobbs
(Opportunities to make numerical analysis jokes don't come round that often.)
-- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
I do know one Russian mathematician who lives in England, but Chebyshev never did.
-- Bill Sloman, Sydney
It /does/ look like that, doesn't it - or at least a really badly terminated transmission line :)
OTOH on the Severn at Portbury Docks there is a nice sinewave.
A bit further upstream at Sharpness Docks it looks more like a half-wave rectified signal (the docks/canal are behind lock gates)
Further upstream at Minsterworth, where the bore is at its highest, it looks like an RC response to an impulse.
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