Tides - Who's got the crystal ball?

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sahona
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Tides - Who's got the crystal ball?

Post by sahona »

WXtide, down-loadable from the Web, doesn't agree with Reeds 2008, and, I suspect neither agree with the predictions built into my chart-plotter. So, where is the DEFINATIVE tide prediction information held?
Or, is it all a very imprecise art... I've already observed that 'tidal constants' are anything but constant. So, as I sit here planning to run down to Ireland, who do I believe? One thing's for certain, I'm not going direct to Ballycastle hoping to hit slot between the swirlies after a ten hour run.
When we go, it will be from Troon at HW Dover, overnight towards Glenarm, or maybe somewhere else, depending on conditions and SWMBO. Then it will be Guinness, sausage and champ (in that order), if only we could find HW Dover.....
http://trooncruisingclub.org/ 20' - 30' Berths available, Clyde.
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Windfinder
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Re: Tides - Who's got the crystal ball?

Post by Windfinder »

Or, is it all a very imprecise art...
I think so, the actual and predicted never seem to tie up here:

http://www.pol.ac.uk/ntslf/sadata_tgi_n ... uth&span=1
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ljs
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Post by ljs »

Or you could overnight at Campbeltown from where its an easyish 5 hour trip to Ballycastle or Rathlin in one tide - as we did last wednesday.
Saw you rafted up on the pontoon in C'town near the shore end but didn't look anyone on board and we were due out at 5.30 am. If you leave at HW Dover (Reeds), round the mull and point at Glenarm you should end up in Rathlin Sound with an hour or so to spare of favourable tide


Edit - just seen this was posted on May 19th so my reply may well be out of date!
Windfinder
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Post by Windfinder »

ljs wrote:so my reply may well be out of date!
To be honest if the solution to a problem involves a night in Campbeltown I'd rather deal with the problem! :D
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DaveS
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Re: Tides - Who's got the crystal ball?

Post by DaveS »

Windfinder wrote:
Or, is it all a very imprecise art...
I think so, the actual and predicted never seem to tie up here:

http://www.pol.ac.uk/ntslf/sadata_tgi_n ... uth&span=1
These are very interesting graphs. By my reading of them the errors are not huge, just over 0.1m at worst. (OK, if you're grounded and trying to refloat that might mean the difference between success and failure...) It would be interesting to construct a third line, "astronomical prediction corrected for observed atmospheric pressure" to show the residual error.

re. Campbeltown: I spent a night there last year, and found it better than I expected: friendly welcome, reasonable food & beer, and unlimited free internet access at the library / swimming pool.
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Telo
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Post by Telo »

Windfinder wrote:To be honest if the solution to a problem involves a night in Campbeltown I'd rather deal with the problem! :D
You just don't know how to enjoy yourself. 8)

Anyway, apart from its unfortunate name, I quite like it. It's, errmm, different.

Oh, and if you get a chance, for an entertaining evening out, you could do worse than calling in at Scotland's oldest extant purpose-built picture house. A rare treat.

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Windfinder
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Re: Tides - Who's got the crystal ball?

Post by Windfinder »

DaveS wrote:
Windfinder wrote:
Or, is it all a very imprecise art...
I think so, the actual and predicted never seem to tie up here:

http://www.pol.ac.uk/ntslf/sadata_tgi_n ... uth&span=1
These are very interesting graphs. By my reading of them the errors are not huge, just over 0.1m at worst.


Agree, I guess tidal predictions seem never to be quite right but equally they seem never/rarely to be meaningfully wrong.

Mind ewe, I've heard VTS Sotton announce that HT was 30cm under predicted. I did once see someone stuck high an dry on on piles when the high tide was massively under prediction (and massively below the previous and next high tides).

To all re Campbeltown:
Sorry! I've only been there once and (to us) the people made Royston Vasey inhabitants seem normal. However we did have a good night so I'm probably being a bit harsh! I did get the feeling that the payment for the Curry (in a deserted curry house) and Beers (in a deserted pub) was about 90 per cent of the outside investment the town was likely to get that year! But we liked it in the way you might like a lame pony struggling along. :lol:

GREAT photo! I've mailed to the people I was with that trip...
garredfox
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Post by garredfox »

We find Belfield Tide Plotter quite accurate.
Go to www.tideplotter.co.uk for details.
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sahona
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Post by sahona »

LJS, sorry to have missed you in Campbelltown. Next time we go across, I'm hoping to do the north, so may be in your neck of the woods.
http://trooncruisingclub.org/ 20' - 30' Berths available, Clyde.
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Clyde_Wanderer
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Post by Clyde_Wanderer »

Never mind the tides, its more important to get the drink/food in the proper order, and I suggest the sausage and chap first as one can overdo it with the guiness first and then not be able for the food.
I remember years ago a doctor in Sligo telling someone to drink more guiness to help him loose weight, as it would suppress his appitite for food, as he was having only a dozen or so pints then going home and eating 20 or so spuds and a couple pound of stake before returning to the pub to wash it all down with another dozen pints o the black stuff.
Oh and remember the guiness must be drank first leaving the creamy head until last. :)
Good luck, Slainte
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