is, but I know we've got just 2 shifts left for each watch. The weather
has become very cooperative; the gentle rocking of the vessel reminds us
that we are at sea, but is not much of a hindrance to our productivity.
We continue to CTD and core across, along, and around the Poverty Bay
margin. Some of you might be wondering what the heck a CTD is. Briefly,
this instrument measures the Conductivity (salinity), Temperature and
Depth of the water, along with some other parameters, such as dissolved
oxygen, light transmission (related to turbidity) and flouresnce (related
chlorophyll), depending on the system. We deploy this instrument over the
side of the ship and lower it to the bottom. During the profile we can
watch the data on a computer display. The CTD is also connected to a
water sampling system which allows us to "fire" a water bottle at a given
depth and collect a water sample. We typically do this so we can measure
the amount of turbidity in the water at specific depths to compare with
the instrument-measured data. That's probably enough detail. Attached are
a couple of related pics: one of Kristen and Caroline taking water from
the CTD's Niskin bottles. Two of Reide directing a CTD deployment
(including one taken from a small boat). Also, you can see a close-up pic
of the Poverty Bay coastline as well as an image of the multicore meeting
the Waipaoa River Mouth.
At this point, we have completed over 50 stations and have deployed and
recovered equipment over 100 times. There have been a few hiccups,
including a couple lost tagline poles and a CTD brushing of the bottom,
and few problems continue to pose challenges including a burned out
erosion chamber motor and a struggling x-ray system. But all in all,
things are going well. After completing a long trancsect of CTDs from
from the river mouth to the outer shelf, we ran a short survey over
Lachlan Canyon. This provided some valuable additional data on the
sediment cover of this region, adding to our existing dataset from
previous cruises to understand sediment thickness and character. Of
course, we still have more mud to collect. I better get down to the deck
because my watch starts in 10 minutes!
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