2008 - My Quest for 150' viz

[Rainer]

Isn't the absolute visibility limit in water less than 300'? I'm having a hard time accepting these claims in this thread of vis better than that.

 

[Tom Winters]

Just hop on I-10 and drive over to Vernon, FL, right down the track from Ebro, and figure out how to dive Cypress Springs. The viz runs 300' laterally, so to keep it down to 150', muck up your mask a little.
The Florida northern meshcarpet baggers southern Alabama wiregrass grazers can help you set this all up. You might want to drag some crawdads and some of those fine Louisiana brews over for them since they're a little deprived up thataways..

 

[knotical]

Isn't the absolute visibility limit in water less than 300'? I'm having a hard time accepting these claims in this thread of vis better than that.

I too wondered what the theoretical maximum visibility in water could be.

The secchi disk is a standard technique for determining the clarity (visibility) of water.
See for example: http://en.wikipedia.org/wiki/Secchi_disk

This site: http://dipin.kent.edu/secchi_records.htm
says both the theoretical maximum and the record secchi disk depth is 80 meters.

However, I wondered if horizontal distances could be greater because the disk would be illuminated from above by light that has not been absorbed as much, especially in shallow waters. This document: www.rsnz.org/publish/nzjmfr/1995/65.pdf
agrees that the vertical theoretical and actual maximums are about 80m.
But (surprising to me) it says the horizontal theoretical max visibility is only 74m.


On a different note: Great visibility implies few particles in the water column, meaning little for critters to eat, so potentially fewer neat things to see.

 

[deepblueme]

Went to Bonaire a few years back had great dives but the vis sucked (for there) about 60 feet best of times. There was some kind of bloom going on so thick it looked like it was snowing on some dives.
Like Roatan Man I have my face in the reef lookin for the TINY things so vis is relitive.

 

[Taxgeek]

Mmmmmm crawfish . . . dang, now you're making me hungry! I should change the thread to "Dive Resort with Best Restaurant!" humph! Thanks all.

 

[Rainer]

I too wondered what the theoretical maximum visibility in water could be.

The secchi disk is a standard technique for determining the clarity (visibility) of water.
See for example: http://en.wikipedia.org/wiki/Secchi_disk

This site: http://dipin.kent.edu/secchi_records.htm
says both the theoretical maximum and the record secchi disk depth is 80 meters.

However, I wondered if horizontal distances could be greater because the disk would be illuminated from above by light that has not been absorbed as much, especially in shallow waters. This document: www.rsnz.org/publish/nzjmfr/1995/65.pdf
agrees that the vertical theoretical and actual maximums are about 80m.
But (surprising to me) it says the horizontal theoretical max visibility is only 74m.


On a different note: Great visibility implies few particles in the water column, meaning little for critters to eat, so potentially fewer neat things to see.

That jives with what I had seen quoted before (roughly 240'). Salt water with particulate should be much less than this maximum. Just don't know where people are getting numbers like 500-600' visibility! Thanks for the links.

 

[drbill]

Isn't the absolute visibility limit in water less than 300'? I'm having a hard time accepting these claims in this thread of vis better than that.

I guess the theoretical types just can't accept reality when it differs from their predictions.

Seriously, I'm only quoting what Norbert Wu says about the vis down there. One of my dive buddies dove there and also said it was pretty awesome, but I don't remember her estimates. Another friend who dives there regularly says that in the area she dives it only gets up to about 80 ft, but on the other side of the peninsula you can get visibility on the order stated.

Guess we'll have to write a grant to get the funding to go down and see for ourselves!

 

[knotical]

Guess we'll have to write a grant to get the funding to go down and see for ourselves!

Hi Bill,

Thanks for mentioning Norbert. With that lead, I found this on the website of the NSF, no less!
“Wu visited the continent in 1997, 1999 and 2000--scheduling his dives from October through December, the best months for filming under the ice. Antarctic waters are the clearest in the world, with visibility sometimes approaching a quarter mile.”
( from: http://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=100171 )

And this at http://scilib.ucsd.edu/sio/nsf/diving/index.html
“Rob Robbins, the Scientific Diving Coordinator at McMurdo Station, estimates average underwater visibility in spring at 300 - 600 feet (91 - 183 meters).”

Maybe the NSF and UCSD should be approached for the grant. Although if I were reviewing the application, I’d ask questions like: “Why can’t we do this with some long pipes and a bunch of distilled water, rather than sending Dr. Bill all that distance?”

 

[knotical]

edit: the last quote I cited above is now at:
Diving Under Antarctic Ice

 

[Crawl79]

Try Fernando do Noronha an insland in Brasil, great vis (150ft common) and great wrecks.