Determining wave hieght with a depth sounder
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- Steve Laume
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- Location: Raven1984 Cape Dory 30C Hull #309Noank, CT
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Determining wave hieght with a depth sounder
I have just started reading Ten hours until dawn, by Michael Tougias. It is a rescue/survival story during the blizzard of 78 off the MASS coast. A great read so far. Kind of like the Perfect storm only closer to shore with more factual information about what acctualy happened. At one point they mentioned that the depth sounder was not working and they were trying to determine wave height at the same time. I may have been reading something into the sentence but it seemed like the two were linked. My hopefully worthy question: can wave height be accurately determined with a depth sounder? I know it would not work in choppy seas. I am thinking about large ocean waves or swells that would allow you to run broad side in the troths, to get to the bottom of things, so to speak. With a flat bottom you could measure the wave height by the difference in depth readings. Did I just wake up, this being common practice? Would it work or am I all wet? Great book anyway, Steve.
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Wave height
Hi Steve,
Your post is worthy from where I sit. Sorta makes me think.
I don't ask if this is THE way to determine wave heights. I'm wondering if this is ONE of the methods to determine them?
If so, how do you think that this is done? Would you measure the heights of the crest and the trough and then divide that difference in half to arrive at a mean average or wave height?
It seems that back in time, I read something about satellites somehow recording sea conditions. I don't know if wave heights were included in this process.
Just wondering,
O J
Your post is worthy from where I sit. Sorta makes me think.
I don't ask if this is THE way to determine wave heights. I'm wondering if this is ONE of the methods to determine them?
If so, how do you think that this is done? Would you measure the heights of the crest and the trough and then divide that difference in half to arrive at a mean average or wave height?
It seems that back in time, I read something about satellites somehow recording sea conditions. I don't know if wave heights were included in this process.
Just wondering,
O J
- Parfait's Provider
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berthed Whortonsville, NC
Satellite Measurements
Indeed, the forecasters use satellite measurement. See http://www.oceanweather.com/forecast/About/index.html
Keep on sailing,
Ken Coit, ND7N
CD/36 #84
Parfait
Raleigh, NC
Ken Coit, ND7N
CD/36 #84
Parfait
Raleigh, NC
- M. R. Bober
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- Location: CARETAKER CD28 Flybridge Trawler
NOAA Sea Buoy--real time--info
Try this URL. Most the of buoys report wave height.
Mitchell Bober
Sunny Annapolis (Within easy driving distance of the FAMOUS Groundhog Extravaganza), MD
http://www.ndbc.noaa.gov/
Mitchell Bober
Sunny Annapolis (Within easy driving distance of the FAMOUS Groundhog Extravaganza), MD
http://www.ndbc.noaa.gov/
CDSOA Founding Member
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Re: Determining wave hieght with a depth sounder
Interesting, but I have a question. Other than as the baseline from which you can increase the height each time you retell the story to your grandchildren, and so that you know how scared you should be, is there any practical purpose to knowing the height of waves you're already out in?
Fair winds, Neil
s/v LIQUIDITY
Cape Dory 28 #167
Boston, MA
CDSOA member #698
s/v LIQUIDITY
Cape Dory 28 #167
Boston, MA
CDSOA member #698
Anyone know just how the weather buoys...
measure wave height? My guess is that it is some sort of inertial device rather than a sonar, because it would provide a more continuous feedback than pulsing sonar, which would be difficult if not impossible to tie to wave crests/troughs. And some sort of adjustment would need to be incorporated to account for the changing waterline on the vessel (bouy, boat) when on a crest vs. in a trough.
Tod Mills
Montgomery 17 "BuscaBrisas", Sandusky, OH (with trips elsewhere)
Tartan 26 project boat
Cape Dory admirer
Montgomery 17 "BuscaBrisas", Sandusky, OH (with trips elsewhere)
Tartan 26 project boat
Cape Dory admirer
- winthrop fisher
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cd 22 "Easy Rider Sr" 84
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- Joe Myerson
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It is a great book.
I'm afraid I can't add anything to the wave-height discussion, but if you're looking to read a great nonfiction book about some heroic mariners (and the horrendous Blizzard of 1978), by all means read Michael Tougias' book. I couldn't put it down.
--Joe
--Joe
Former Commodore, CDSOA
Former Captain, Northeast Fleet
S/V Crème Brûlée, CD 25D, Hull # 80
"What a greate matter it is to saile a shyppe or goe to sea."
--Capt. John Smith, 1627
Former Captain, Northeast Fleet
S/V Crème Brûlée, CD 25D, Hull # 80
"What a greate matter it is to saile a shyppe or goe to sea."
--Capt. John Smith, 1627
Re: Determining wave hieght with a depth sounder
I always record wave height in my log book, useful? maybe not. But if your on a passage and checking in with someone like Herb it helps him to know accurate sea states.Neil Gordon wrote:Interesting, but I have a question. Other than as the baseline from which you can increase the height each time you retell the story to your grandchildren, and so that you know how scared you should be, is there any practical purpose to knowing the height of waves you're already out in?
Russell
s/v (yet to be named) Tayana 42CC
s/v Lady Pauline Cape Dory 36 #117 (for sale)
s/v (yet to be named) Tayana 42CC
s/v Lady Pauline Cape Dory 36 #117 (for sale)
- winthrop fisher
- Posts: 837
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- Location: Typhoon Wk 75 "Easy Rider" &
cd 22 "Easy Rider Sr" 84
oh Neil G
you are so funny
Neil Gordon wrote:Winthrop is right.winthrop fisher wrote:... look at the mast to get the roughed height.
Climb to the top of the mast. If you're still looking up at the waves, you're in major trouble.