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    Re: Glowing Sea Surface
    From: Trevor Kenchington
    Date: 2003 Nov 11, 00:22 -0400

    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@iStar.ca
    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

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