According to Chapman;

MLW: the avg. height of all low waters at a place over a 19-year cycle.


MLLW: the avg. height of the lower low waters over a 19-year cycle.

SV


"Jeff Morris" jeffmo@NoSpam-sv-lokiDOTcom wrote in message
...
No - LAT is "Lowest Astronomical Tide" or the lowest tide that would be
predicted. LLWLT,
or "Lower Low Water Large Tide" is the average of the lowest low water for
each year in a
19 year cycle.

Presumably, LAT would be the lowest of the lowest low water in the 19 year
cycle, not the
average.



"The_navigator©" wrote in message
...
Here (and the UK I believe) it is the "lowest astromical tide". If you
think about it, that is the only sensible datum for a _sounding_!

Cheers MC

Jeff Morris wrote:

If you were going to take the time to look it up, you could have at
least said how it
is
defined.


"Donal" wrote in message
...

"Jeff Morris" jeffmo@NoSpam-sv-lokiDOTcom wrote in message
...

How old is that chart? All of my US charts from the recent past use
MLLW

as the datum for

soundings. I even checked in my Chesapeake ChartKit to see if they
were

different.

OK - Here's a quiz: What's the meaning of LLWLT?

Lower Low Water Large Tide.


Sounds similiar to LAT.


Regards


Donal
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