What is visibility?

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A lot of warm water divers have no idea what a place like the North Coast can be like on a nice day. Truly world class.

Well, don't advertise it man! We'll have every once-a-year cruise ship diver crowding every cove north of Jenner! :)
 
Make a "secci disk"-- the accepted method of measuring UW visibility

Mine were made from a number of 2 inch diameter aluminum disk each side painted 1/2 black and the 1/2 white which was attached to a line at various distances.

It is interesting what is perceived and what is the actual visibility-- the differences between the horizonal and vertical visibility

A great tool for teaching (And a $500.00 PADI Inc specialty -"UW Visibility measuring" )

SDM
 
Warm water gin clear divers tend to rate visibility when things begin to diminish, and cold water pea soup divers tend to rate visibility when objects pretty much disappear completely.
It’s highly subjective.
To me, if I can see the end of my spear gun it’s a good day.

Up here on the Great Lakes, you have better viz at the beginning of the season with colder water. If I have 30ft plus viz, it’s a great day! The quarry, on the other hand, has a boatload of particulate in the water. Add algae and heavy rain, and viz goes pretty much to zero. Good quarry viz is 10ft. Buddy and I cancelled our quarry dives today as the heavens have been open for the past 24 hours and we wouldn’t be able to see past arm length.
 
@Marie13

With the passing of the seasons first good rain event it is appropriate to remind you to think about the hazards that could be encountered during a dive.

Runoff from streams, streets and storm drains will carry oils, pesticides and other contaminates into the creeks, rivers terminating in the closest body of water that offers accumulation.

As the rainy season becomes mature agricultural runoff, fecal material and high levels of bacterial contamination can be expected.

If you MUST dive it is suggested

* A week be allowed after the OK for ocean to purge it's self of contaminates

* Avoid diving in the near the creeks and streams

* After a questionable dive always wash with soap and water as soon as possible.

* Immediately rise the inner ear canal with appropriate anti- bacterial solution

* Make a concerted effort not to ingest any water you have been diving in or have made contact.

* Routinely check any cuts and scrapes for redness and swelling that may indicate infection. If persists suggest seeking medical assistance.

* Monitor long term coughs and irritated throats which are often a result of contaminated water diving.

Enjoy but be careful after a big rain that produces excessive run off Remember it is not the local runoff but that run off with it's origin many miles away from the dive site...in the surrounding area that brings the bad stuff to the quarry

Stay healthly wealthy and wise -- well 2 out of the three is acceptable

SAM Miller, III

DD
 
i measure viz as when objects become recognizable, maybe not in detail but i know what im seeing.
measure your kick cycles (mine are 4.5' per frog kick). then when you first see a stationary object, count how many kicks it takes to get to it. that will give you a good idea of viz.
generally rain washes sediment into the water and reduces viz. wind causes wave action to stir up the shore and reduce viz. warm water holds sediment more than cold water (especially at thermocline).
but the number one reason for poor viz is lots of bad divers! dont be that guy!!! stay off the bottom, use frog kicks and never kick with your legs aiming down.
 
At one of my local sites, the visibility varies greatly. In this shot of a small Lingcod you can barely see past its tail. Visibility that day was less than three feet. My strobes lit the area, making it look better than it really was.
45202135054_0504c9e35a_o.jpg


When conditions were at their best, which is rare we had blue water at the same site. I could see our boat from sixty feet below.
Merry on the line_edited-1.jpg
 
Wintertime rules for clear water on the NC.

I've had my best diving then. Just have to be lucky to have time off when the weather is right. Get to meet the surfers instead of the tourists.

To me, if I can see the end of my spear gun it’s a good day.

When I get in the water and I can see my fins, it will be a good day. And the NC can be unpredictable, a number of times I've found the viz near zero from a plankton bloom and at five to ten feet the viz opens up to thirty or more.

Well, don't advertise it man! We'll have every once-a-year cruise ship diver crowding every cove north of Jenner! :)

I think they will have more than one logistical problem with that.



Bob
 
Well, don't advertise it man! We'll have every once-a-year cruise ship diver crowding every cove north of Jenner! :)
Well, when there was an abalone season that might have been true.
Since they closed abalone diving there has been a very sharp decrease in the amount of people you see on the beaches wrapped in rubber. However, campgrounds haven’t really slowed down much because there’s been a huge boom in camping overall, so what used to be abalone divers camping has now been replaced with general camping.
Not too many people scuba diving. Sometimes I’m the only diver for miles around. Lot’s of tourist though beach combing, more than ever, from all over the world. They look at me like I’m nuts.
 
upload_2019-9-28_9-32-23.jpeg

Here’s Sea Ranch on a really nice day. Vis is probably 30’+
Would you get adventurous and do a shore dive on your own? Even though the water is probably 52 degrees? There’s a trail to climb you know.
How many people on SB are self sufficient enough and seasoned enough to dive a place like this, or anywhere anytime without any diving infrastructure, no guides, no babysitting, no dive shops.
I didn’t think so.
This is why nobody dives up here.
 
https://www.shearwater.com/products/teric/

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