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From: David Weilacher (no email)
Date: Fri Jul 23 2004 - 07:42:03 EDT
Hi Jarad;
Can you point me to your source for Noaa wave height definition?
Dave W
-----Original Message-----
From: Jared Sherman <>
Sent: Jul 22, 2004 9:34 PM
To:
Subject: Re: Level of observation accuracy in medium seas
Dave-
<50 foot waves with a mile between peaks. I take my shot when my boat is
at the top of a wave. This is easy to tell because I can actually see a
horizon. The horizon I see is 8 miles away.>
Seems like short horizon. NOAA says that waves are measured from the sea
level, not from the trough to peak, so are you talking about real fifty foot
waves, or "real" 50 foot waves, which most sailors would call hundred
footers?<G>
If the former, you're observing from 25' above sea level, figure ten more
for your deck and standing eye height, since you've got a good enough grip
to rider those doggies.<G> That's 35' asf now, about your eight miles.
(7.9+)
Nah, you're only in 25' waves, that's the problem. Wait for rougher weather,
you'll get a better horizon.<G>
But you could certainly figure the math. A sphere (close enough<G>) 25,000
miles in circumference, two points 8 miles apart on that. Change the radius
of one by the 25' your far wave is blocking you...run some tangents and
angles..."A simple exercise left to the reader."
Just remember, you're only in 25' waves.<G>
Dave Weilacher
.US Coast Guard licensed captain
. #889968
.ASA instructor evaluator and celestial
. navigation instructor #990800
.IBM AS400 RPG contract programmer
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