I do not know about the specific reason for the layering at Duncans Cove.
In general, there are two variables involved:
Temperature and Salinity:
Temperature:
In a body of water of constant salinity, warm water can form a layer on top
of a cold main water column. This is often noticed in lakes while swimming.
In the ocean, due to stronger mixing (wind/wave action), a warm layer tends
to be thicker (generally at least a few meters) than in a lake.
Salinity:
The water density increases with salt content. Thus, fresh water (rain,
river runoff) can form a less salty top layer in the ocean. In the area of
Duncans Cove, many streams originate in boggy conditions, with a typical
brownish colour. In late summer, this water may also be warmer than the
ocean water, further stabilizing the layer.
To know for sure, oceanographers would measure salinity and temperature
over depth, and the profile would likely show a Thermocline (
https://en.wikipedia.org/wiki/Thermocline) and a Halocline (salt layering) (
https://en.wikipedia.org/wiki/Halocline).
Burkhard
On Fri, Nov 12, 2021 at 5:54 PM nancy dowd <nancypdowd(a)gmail.com> wrote:
In this very interesting Nov 8 interview on CBC’s
Mainstreet re a 10’
Great White Shark encounter off Duncan’s Cove
https://www.cbc.ca/listen/live-radio/1-37-mainstreet-ns/clip/15877446-an-un…
I
was wondering about the reason for the water layering mentioned, murky up
top and clear well below, at this time of year in this area. Anyone?
Thanks
Nancy D
Sent from my iPad
_______________________________________________
Naturens mailing list -- naturens(a)chebucto.ns.ca
To unsubscribe send an email to naturens-leave(a)chebucto.ns.ca