Would I be right in saying that one should add 1 hour to the tide times produced by the \"easytide\" web site right through the summer? It says so, I\'m just sanity checking.
Also if HW is say 13:00 hours when will the next ebb be at its strongest?
Tides,again
Re:Tides,again
Q1 - Yes. Click on the box to apply 1 hour...
Q 2. It can be complicated. It depends where you are. Go on a L4 course!
Q 2. It can be complicated. It depends where you are. Go on a L4 course!
Re:Tides,again
Yes. Ciaran, this is called the rule of thirds and applys from slack water. To find out when slack water happens in relation to HW, you need Oileain, the Pilot or the Sailing Directions.
Re:Tides,again
maybe it only exists in West Cork?
Here are two rules to confuse ya.
Jim Kennedy
www.atlanticseakayaking.com
TIDES AND CURRENTS
Two rules help estimate the height of tide and its associated currents at different stages of the tide cycle. The “Rule of Twelfths” estimates tide heights between high and low water. Over the six-hour period between any high and low tide, 1/12 of the volume of water will move in the first hour, 2/12 will move in the second hour, 3/12 will move in the third hour, 3/12 will move in the fourth hour, 2/12 will move in the fifth hour, and the last 1/12 will move in the sixth hour
The “50-90 rule” estimates current speeds between slack water and maximum flow. Divide the time between slack water and maximum ebb or flood into thirds. In the first third, the current will increase to 50% of its maximum. In the second third it will reach 90%. And in the last third, it only increases the last 10%.
Here are two rules to confuse ya.
Jim Kennedy
www.atlanticseakayaking.com
TIDES AND CURRENTS
Two rules help estimate the height of tide and its associated currents at different stages of the tide cycle. The “Rule of Twelfths” estimates tide heights between high and low water. Over the six-hour period between any high and low tide, 1/12 of the volume of water will move in the first hour, 2/12 will move in the second hour, 3/12 will move in the third hour, 3/12 will move in the fourth hour, 2/12 will move in the fifth hour, and the last 1/12 will move in the sixth hour
The “50-90 rule” estimates current speeds between slack water and maximum flow. Divide the time between slack water and maximum ebb or flood into thirds. In the first third, the current will increase to 50% of its maximum. In the second third it will reach 90%. And in the last third, it only increases the last 10%.
Re:Tides,again
Mike
Des put you right, but you mayn\'t have picked up on it? Flow rates are calcuated from \"slack water\" not \"high water\".
High water is when the water stops its VERTICAL movement upwards and will begin going down again, while slack water is when the water stops its HORIZONTAL movement in one direction and will begin flowing in the reverse direction.
At any given spot, these two events may occur at substantially different times. This appears to be the case at Cuan Sound. If you tell me where that is, I will give you the specifics.
The rule of twelfths (same as the one third two thirds three thirds rule) relates only to vertical movement. The 50/90 rule applies only to horizontal movement.
The main use made by kayakers of the rule of twelfths is deciding where to put in, in terms of a possible long carry up or down a strand, a muddy harbour, or other inconvenience. The 50/90 rule is used much more often, mainly navigation. Going along the coast its nice to have the horizontal water movement with you, but crossing a channel, it may be nice to go when the movement is least ?
Singly the most important new piece of information learner sea-goers need to get firmly into their head is the concept of SLACK. High and low water are trivial matters by comparison.
DWalsh
Des put you right, but you mayn\'t have picked up on it? Flow rates are calcuated from \"slack water\" not \"high water\".
High water is when the water stops its VERTICAL movement upwards and will begin going down again, while slack water is when the water stops its HORIZONTAL movement in one direction and will begin flowing in the reverse direction.
At any given spot, these two events may occur at substantially different times. This appears to be the case at Cuan Sound. If you tell me where that is, I will give you the specifics.
The rule of twelfths (same as the one third two thirds three thirds rule) relates only to vertical movement. The 50/90 rule applies only to horizontal movement.
The main use made by kayakers of the rule of twelfths is deciding where to put in, in terms of a possible long carry up or down a strand, a muddy harbour, or other inconvenience. The 50/90 rule is used much more often, mainly navigation. Going along the coast its nice to have the horizontal water movement with you, but crossing a channel, it may be nice to go when the movement is least ?
Singly the most important new piece of information learner sea-goers need to get firmly into their head is the concept of SLACK. High and low water are trivial matters by comparison.
DWalsh
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ciarancarthy
- Posts: 0
- Joined: Sat Oct 26, 2013 9:37 am
Re:Tides,again
I\'d like to pick up a good text with the local info on this.
Can somebody recommend what and where to acquire?
Can somebody recommend what and where to acquire?
Re:Tides,again
\"the local info on this\" ?
DWalsh
DWalsh
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ciarancarthy
- Posts: 0
- Joined: Sat Oct 26, 2013 9:37 am
Re:Tides,again
I mean when slack water occurs in each place around the country.
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alanhorner
- Posts: 0
- Joined: Sat Oct 26, 2013 9:37 am
Re:Tides,again
Ciaran
do us all a favour
GO ON A LEVEL 4 COURSE.....
AND
Buy Oilean OR The Coastal Pilot
.......for Slack water info. and a lot more
AND
Check the Tides Link on this website for Local High & Low water
against which the Slack water constants are shown.
Alan
do us all a favour
GO ON A LEVEL 4 COURSE.....
AND
Buy Oilean OR The Coastal Pilot
.......for Slack water info. and a lot more
AND
Check the Tides Link on this website for Local High & Low water
against which the Slack water constants are shown.
Alan