Tidal streams diamond reference ports list ?

Boo2

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Hi,

Anyone know where there exists a list of all the tidal streams reference ports that are referred to on Admiralty charts for the UK ? I have charts referring to Plymouth (Devonport), Portsmouth & Dover but I assume there are quite a few others.

Boo2
 
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Tiller Girl

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Never seen a list but going north from Dover you can add Sheerness, Harwich, Immingham, River Tees Entrance, River Tyne (North Shields), Leith, Rosyth, Aberedeen, Illapool - if everyone else adds, you can make the list.:encouragement:
 

lpdsn

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Dublin, Belfast, Greenock, Liverpool, Cork.

In fact, seems to tie up quite well with the list of primary ports in Reed's.
 

bitbaltic

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Dublin, Belfast, Greenock, Liverpool, Cork.

In fact, seems to tie up quite well with the list of primary ports in Reed's.

Indeed. Admiralty Easytide FAQ says:
All tidal stream data, where available, is contained on the largest scale Admiralty Charts of the particular area concerned. In the main it takes the form of the position marked by a Tidal Stream Diamond, which then refers to a table of Mean Spring and Mean Neap Rates and Directions for the whole tidal cycle, that is, from 6 hours before to 6 hours after the time of High Water at a suitable reference port (Standard Port).

http://www.ukho.gov.uk/EASYTIDE/EasyTide/Support/faq.aspx

Wikipedia:
Somewhere on the chart, generally on land, will be a Tidal Diamond table. This contains a grid of thirteen rows and three columns for each Diamond. The rows are the hours of the tidal cycle showing the 6 hours before high water, high water itself and the 6 hours after high water.[1] The columns show the bearing of the tidal stream and its speed, in knots, at both spring tide and neap tide. The times on the table are related to the high water of the standard port displayed on the table.

https://en.wikipedia.org/wiki/Tidal_diamond

I think we can be pretty sure that tidal diamods will only relate to standard ports rather than secondary ones (on reasonably modern charts). Whether every standard port has spawned a diamond, however, might depend on the coverage and scale of different charts produced by the different publishers. At least in proper Admiralty (rather than leisure folio) terms, I would guess every UK standard port has lent its data to at least one tidal diamond on at least one chart at some scale or other.

A list of Standard ports can be formulated by browsing through the secondary differences tables of any copy of Reeds'.
 

Boo2

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OK, the list so far is :

Plymouth (Devonport)
Portsmouth
Dover
Sheerness
Harwich
Immingham
River Tees Entrance
River Tyne (North Shields)
Leith
Rosyth
Aberedeen
Illapool
St Helier
Dublin
Belfast
Greenock
Liverpool
Cork
Zeebrugge
Dunkerque
Vlissingen
Hoek van Holland

I removed Portland as all the charts for that area seem to refer to Plymouth instead. Anyone know any more ?

(I did see the posts re obtaining standard ports from Reeds etc but I need to know the tidal diamond reference ports only so if some of the standard reference ports don't have TDs than that's no use).

Thanks,

Boo2
 

Boo2

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I am intrigued to know why you want you want such a list
+ 1. Unless for some academic reason.
Presumably so he knows what tidal info he needs to carry. But they're all in the almanacs anyway, even the small boat one.
I am thinking of writing some software that permits the user to enter tidal diamond info and then displays the tidal stream as a function of time.

This requires either tidal harmonics for the ports referred to by the diamonds or else the reference tide height info to be entered which is onerous because it changes every day. So before I start I want to findout whether I can obtain harmonics for all standard ports referred to by tidal diamonds on charts.

Boo2
 
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CornishJohn

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I'm still puzzled by your real goal here.

Is this software you intend to distribute? You will have to negotiate a license with UKHO if that is the case, and they provide Totaltide for the very same purpose. Lookup "Xtide" for a case history.

If for personal use only, you will get the required answer on a case by case basis anyway. I will be rather surprised if there is a Standard Port without a tidal diamond nearby. But even with the harmonics, you will need to identify springs and neaps for the software to work.

UKHO Admiralty Tide Tables (NP201) will tell you about all the Standard Ports and their harmonics. The contents are not freely distributable however.

I'm not directly connected with UKHO at all, but do work in a very closely related field.

Good luck anyhow,

j
 
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