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[hvered]

A 'super tide' around Mont St Michel has attracted thousands of visitors -- it's said to be a consequence of the eclipse. Why the tide is so high there but not it seems along the rest of the Breton coast isn't clear.

[Mick Harper]

As Boreades has pointed out, this is a special 'moon' since it is the moment when it approaches closest to the earth. So this is one reason why the tide is 'super'. It is not the actual eclipse that is important but the fact that the sun and moon are in the same place ie presumably exerting maximum directional gravity. Mont St Michel has the biggest tidal race so my guess is that it only seems to be more super there than anywhere else on the coast (either coast for that matter).

But this is all very orthodox. The real reason needs identifying.

[TisILeclerc]

Taken from France24 which goes on to say

'Saturday’s high tide was the first in nearly a month of remarkable water surges due to culminate on March 20 and 21 with tidal coefficients of 118 or 119 respectively.

The second day has been touted as "the tide of the century" -- a considerable misnomer, since the ocean rises to that peak level every 18 years.'

I'm not sure what 'tidal coefficients' are but if the ocean reaches this level every 18 years perhaps the island was used in ancient times as a tidal clock or tide gauge of some sort.

[Boreades]

The real reason needs identifying.

What's real?

Maybe the Perigee Moon and the Saros Cycle will help.

A supermoon is the coincidence of a full moon or a new moon with the closest approach the Moon makes to the Earth on its elliptical orbit, resulting in the largest apparent size of the lunar disk as seen from Earth.[1] The technical name is the perigee-syzygy of the Earth-Moon-Sun system.

http://en.wikipedia.org/wiki/Supermoon

The saros (Listeni/ˈsɛərɒs/) is a period of 223 synodic months (approximately 6585.3211 days, or just under 18 years and 11 days), that can be used to predict eclipses of the Sun and Moon. One saros period after an eclipse, the Sun, Earth, and Moon return to approximately the same relative geometry, a near straight line, and a nearly identical eclipse will occur, in what is referred to as an eclipse cycle. A sar is one half of a saros.

http://en.wikipedia.org/wiki/Saros_%28astronomy%29

The question is, why should the Perigee Moon and the Saros Cycle coincide?

[Boreades]

Two interesting articles;
here
https://chiefio.wordpress.com/2013/01/2 ... unar-beat/
and here
https://chiefio.wordpress.com/2013/01/0 ... -than-one/
on what happens when the peak of one cycle coincides with the peak of another.

The TME bonus is that involves Henges and Druids. And when to plant plants. I'm just off to the greenhouse to talk to mine about this.


A Druid on the ground with a Henge will be observing these various cyclical changes and trying to figure out how to predict them, and what they mean. A Sailor trying to predict the tides will be dealing with these beat frequency effects, too, as they add up to the total pull of the Sun and Moon on the seas. Not all ‘full moon tides’ will be the same size, even though the sun and moon are in a straight line.

I would assert that Stonehenge shows that the Saros Cycle was being ‘researched’ about 3000 BC. The device is capable of it, and the method has been worked out. The 19 lunar holes let you track, over the years, the stage of the orbit; while the Aubry Holes let you model the sun / moon / earth interaction. The inner 19 holes let you track the Metonic cycle while the Aubry Ring lets you track eclipses, so models the Saros Cycle indirectly.

Arr, it's the calendars again!

[Mick Harper]

Well, yes, all very interesting (and informative) but my question really was "Why Mont St Michel?" Any views?

[Boreades]

'What excuse do you use when it's a total solar eclipse?'

Er, wha' 'appened. Where am I? I'm not drunk you know. 'As anybody seen my ship?

As swaying around comes naturally to many of us artistic folk, I wonder how much is all the fault of the moon?

I'm not drunk, ossifer, I'm just in touch with my inner cycles.

The Severn Bore Appreciation Society has a nice graphic on that subject, and the nine year cycle.

http://www.severn-bore.co.uk/bore_cycle.html

[Boreades]

I love this cycles stuff.

There's also a 60 year cycle in the global mean sea level. The volume (or amplitude) varies a bit depending on the ocean, but the number of years (the frequency) is much the same.



We've been in the "upward" part of the current cycle that bottomed c.1985, but we're being told it's Global Warming wot dunnit. Presumably, by this year, 30 years into the cycle, the rate of sea level rise will cease and then start to decline, so then it will have to be Global Warming causes sea levels to fall.

Ref: 2012 paper (Chambers et al, “Is there a 60-year oscillation in global mean sea level?”, Geophysical Research Letters Vol 39 [ http://www.agu.org/pubs/crossref/2012/2 ... 2885.shtml ] )

Why is the CE North Pacific an exception? Dunno, maybe it funnels through the Asia-Alaska gap?

[TisILeclerc]

Any known reason why this happens?

I can't see why it should be blamed on the moon. After all the moon is fairly consistent in what it does and I can't see the perigee etc causing high and low seas over such a long cycle. If it did have an effect it would surely be more immediate.

Is this highness and lowness to do with the earth itself, magnetic fields and all that, or is it caused by an external source such as planetary alignments and so on?

And while I'm here why does the Med not have tides in the same way as the oceans? It's big enough. Even my bath water sloshes about a lot, once a month of course needed or not. Must be the perigee.

[spiral]

Spiro has just discovered a new site, written by "proper" archaeologists http://www.badarchaeology.com/

I cant see them liking ME................

In fact they are going to hate it. Really hate it.... maybe they should be sent a copy.