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Re: Global oceanic tides
From: Trevor Kenchington
Date: 2003 Aug 28, 09:31 -0300
From: Trevor Kenchington
Date: 2003 Aug 28, 09:31 -0300
Dan asked:
> How in the heck do you know all of this? Has your professional work
> caused you to need to learn all of this, or are you a physicist that
> loves to study this?
Tidal phenomena have long intrigued me, though I hadn't bothered with
the theory since slogging through it as an undergrad student
(Oceanography & Zoology -- I'm no physicist nor mathematician!). Some 18
months ago, I took the Power Squadron's "Piloting" class (CPS version,
not USPS) and I knew that whet was said about tidal theory was wrong,
though I couldn't remember what was right. So I started re-reading old
textbooks, which saw my Squadron volunteer me to trial-teach a new tides
module, which caused me to continue reading -- leading to my present point.
> I have always wanted to learn more about the tides
> but have never found the appropriate book. All seem either too
> simplistic
> or way over my head. (I'm a math major with a decent amount of physics
> under my belt.)
>
> Do you have any recommendations for further reading for someone with my
> level of understanding?
There is a good introductory section in the "Reed's Nautical Companion"
(US version) which is also available as a PDF file on their web site,
which would get anyone started.
I have a slim paperback "Ebb and Flow: The Tides of Earth, Air and
Water" by Albert Defant, which was originally published in German in
1953. My English edition dates from around 1970, though the translation
was first published in 1958, so it would likely be hard to find. That
was one textbook back in my student times and explains the phenomena
without much recourse to math. There are likely to be other similar
books aimed at the fringe between professional oceanographers and
serious amateur enthusiasts but I have not gone in search of them.
If you have access to Canadian Hydrographic Service publications, they
do a small leaflet "Tides in Canadian Waters" which is surprisingly
authoritative. They also do a larger manual which is mainly instructions
to their staff on how to set up tide gauges and so forth but includes an
excellent, almost math-free, explanation of what drives tides --
including the only explanation I have every understood of the 18-year tide.
Then there is "Tides: A scientific history" by D.E.Cartwright, published
1999 by Cambridge University Press. That is a study of the history of
science but it leads the reader through much of the thinking and so
serves as an introduction to what became known. It is my only source for
developments in the past 30 years. (Cartwright was a tidal oceanographer
himself before retirement.)
However, as a math major, you might have more success with the
"Admiralty Manual of Tides" than I have had. (I thought that mine was an
update of circa 1970 but, on checking, I see that it is simply a 1973
reprint of the 1941 text.) Somebody posted, a few days back, a note that
implied that the Manual is no longer available from Admiralty chart
agents. However, it ought to be available in major academic libraries.
That is about all I can personally recommend, though there should be
much else available if anyone can find it.
Trevor Kenchington
--
Trevor J. Kenchington PhD Gadus@iStar.ca
Gadus Associates, Office(902) 889-9250
R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251
Nova Scotia B0J 2L0, CANADA Home (902) 889-3555
Science Serving the Fisheries
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