Seamanship Question #32
 

It's high tide. The cycle from High to Low is 6 hours.

What is a quick way to estimate the drop tide height
in the next hour?

Seamanship Question #32
 

"Bart Senior" .@. wrote in message ...
| It's high tide. The cycle from High to Low is 6 hours.
|
| What is a quick way to estimate the drop tide height
| in the next hour?


The rule of thirds??

Cheers,
Ellen

P.S. thanks for sailing content

Seamanship Question #32
 

Ellen MacArthur wrote:
"Bart Senior" .@. wrote in message ...
| It's high tide. The cycle from High to Low is 6 hours.
|
| What is a quick way to estimate the drop tide height
| in the next hour?


The rule of thirds??


Wrong...another lubber I see. The rule of thirds is fo tital stream
flows .

For height you use the rule of 12.

Joe


Cheers,
Ellen

P.S. thanks for sailing content

Seamanship Question #32
 

"Joe" wrote
| Wrong...another lubber I see. The rule of thirds is fo tital stream
| flows .
|
| For height you use the rule of 12.

Don't EVER call this girl a lubber, you farmer! :-)

Rule of thirds works for tide height. In the first two hours it goes down 1/3 of its height.
In the next two hours it goes down 1/3 more and in the last two hours it goes down the last
1/3. (I think.)

Cheers,
Ellen

Seamanship Question #32
 

Ellen MacArthur wrote:

Rule of thirds works for tide height. In the first two hours it goes down 1/3 of its height.
In the next two hours it goes down 1/3 more and in the last two hours it goes down the last
1/3. (I think.)


Wrong.

Joe

Seamanship Question #32
 

"Ellen MacArthur" wrote
| Rule of thirds works for tide height. In the first two hours it goes down 1/3 of its height.
| In the next two hours it goes down 1/3 more and in the last two hours it goes down the last
| 1/3. (I think.)

Oops! That doesn't sound right. Maybe it goes down 1/4 the first two hours and 1/2 the next
two hours and 1/4 the last two hours. Yes, that's it. Makes more sense that way. It goes down
faster in the middle hours.

Cheers,
Ellen

Seamanship Question #32
 

Ellen MacArthur wrote:
"Ellen MacArthur" wrote
| Rule of thirds works for tide height. In the first two hours it goes down 1/3 of its height.
| In the next two hours it goes down 1/3 more and in the last two hours it goes down the last
| 1/3. (I think.)

Oops! That doesn't sound right. Maybe it goes down 1/4 the first two hours and 1/2 the next
two hours and 1/4 the last two hours. Yes, that's it. Makes more sense that way. It goes down
faster in the middle hours.

Bwahahahaha lubber!

Joe

Cheers,
Ellen

Seamanship Question #32
 

"Joe" wrote |
| Wrong.

Maybe your right, Mr. Farmer (sign of respect (-:) Explain how the rule of 12 works.
That's probably what I was thinking. The rule of 1/3 maybe is more for photography.

Cheers,
Ellen

Seamanship Question #32
 

"Joe" wrote


| Bwahahahaha lubber!

OK! You got me. Your not a farmer. (blush, I guess I blew my sailing test debut)

Cheers,
Ellen

Seamanship Question #32
 

Ellen MacArthur wrote:

OK! You got me. Your not a farmer. (blush, I guess I blew my sailing
test debut)

For someone that moans about lack of sailing content in what is widely seen
as a virtual yacht club bar (where the patrons also talk about stuff other
than sailing), you have a lot to yet contribute.

The clue is in the 12ths part...

hour change as a fraction of tidal range
1 1/12
2 2/12
3 3/12
4 3/12
5 2/12
6 1/12

Say the tide drops 5" over the first hour. Since you know that that 5" is
one twelfth of the total range, you can calculate that the tide will have
dropped 5"x12 = 60" = 5 feet when it gets to low water. Of course, 5' is a
girly tidal range. Here, it's a proper, manly 5 metres (or more).


--
Capt Scumbalino