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From: Trevor J. Kenchington (no email)
Date: Mon Nov 10 2003 - 23:22:47 EST
Jared,
You wrote:
> But in answer to your direct question as to whether sea water itself
> emits light...The general answer we learned in oceanography is "no".
> Seawater does not glow at all, by itself.
Thank you. That was the answer I was looking for. (If my undergrad
oceanography courses mentioned this at all, nobody stressed it enough
for the detail to have remained in my memory over the past quarter century.)
I guess that means that what I saw during the hurricane was almost
certainly bioluminescence. It is widespread, of course, and I too have
played with "living sparks" during night dives, seen them over the side
of boats, watched bow waves and wakes glow and all the rest. I can
remember one night, in the Tasman Sea I think, when we stopped for an
oceanographic station and saw a large glowing blob, beyond the reach of
the deck lights. On closer inspection, it proved to be a mass of
colonial gelatinous plankton -- salps I think, though my memory of that
detail may be faulty.
What was different in the hurricane (though close to George's
observations in his cooling-water inlet pipe) was that the glow in the
water was not visible as isolated sparks but rather as if it was
continuous. If it was biological, then there must have been a very large
number of very small organisms -- which implies that they were blooming
in Musquodoboit Harbour at the end of September. As I noted in my last,
that seems a bit improbable, though it clearly isn't impossible.
Just perhaps, it was neither the water itself nor anything living but
rather something non-living suspended or dissolved in the water (other
than the sodium chloride). I don't know what might glow but I also don't
know what flows into the Harbour, down the river, off the road, out of
faulty septic systems or even with leaves blowing off the trees. Harbour
water certainly isn't pure seawater and I'll not rule out a
physico-chemical explanation.
As of this afternoon, I did manage to add another species to the
Harbour's fauna: Got into trouble trying to work off a lee shore in
water too shallow to get the centreplate down and had to resort to
kedging. On one particularly energetic attempt to throw the anchor to
windward, I lost my balance and followed it over the side! The water was
only waist deep but it was not a dignified mode of navigation.
Trevor Kenchington
--
Trevor J. Kenchington PhD
Gadus Associates, Office(902) 889-9250
R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251
Nova Scotia B0J 2L0, CANADA Home (902) 889-3555
Science Serving the Fisheries
http://home.istar.ca/~gadus
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