Dispatch 24 - October 3, 2003
By C. A. Linder
Weather conditions: Overcast skies, 10 kt winds, 2-3 ft seas,
air temperature 33°F
The WHOI mooring redeployment operation continued today, taking advantage
of the settled weather. First, though, we needed to bring some more
yellow floats out of the hold, since
the ones on deck are going fast! Once all of the instruments and floats
were arranged on deck, the mooring team deployed two WHOI moorings.
After yesterday's successful mooring deployments, these two were a
breeze. After dinner Lisa Munger also sent the second Acoustic Recording
Package down to the depths to listen for Bowhead whales.
These two questions come from Mrs. Cadwell's class at Varnum
Brook Elementary School.
Question: How many people does it take to pull in the moorings or is it done by machine?
Answer: The moorings are recovered (pulled in) and
deployed (put out) using a combination of people power and machines.
This photo shows what the fantail of
the ship looks like during a typical mooring deployment. Usually there
are 8-10 people involved in the operation. The WHOI mooring team is
led by John Kemp. He directs the mooring
operation like a conductor leading an orchestra. Ryan
Schrawder and Dan Torres help John attach the instruments to the
mooring line. The Healy's Boatswain's Mates and Marine Science
Technicians tend lines and operate the machines which do the heavy
lifting. One person runs the A-frame and the capstan,
which together take in and let out the mooring line. Three to four
other people tend lines, making sure that the mooring line is held
securely while instruments are being attached. Another person, usually
a very experienced Coast Guard sailor, acts as a safety
observer. It takes a lot of teamwork to deploy these moorings.
Having photographed nearly every mooring recovery and deployment on
this cruise, I can say that this team really makes it look easy!
Question from Josh: How long will it take to read all of the data you are gathering?
Answer: Josh, there is a vast amount of data to read,
analyze, and write papers about. We have collected 14 months worth
of data from the moored instruments on the temperature, salinity,
and currents. Each mooring contains a wealth of information, and having
eight moorings makes the task even greater! Bob Pickart estimates
that it will easily take five years for him and his research team
to go through all of the data.
This question comes from Ryanne, who is a 6th grader
at the Morse Pond School, Falmouth Massachusetts.
Question from Ryanne: Is there ever too much algae,
even though it is at the bottom of the food chain? Are there any such
things as algae blooms?
Answer: Hi Ryanne, thanks for writing. I asked biological
oceanographer Carin Ashjian to answer these questions. She replies:
"Good questions! Yes, indeed, there are algal blooms in the Arctic.
In fact, there are two types. First in the spring there is a bloom
of ice algae. This is algae that grows in and on the bottom surface
of the ice. The sub-bottom ice algal bloom can be huge, with streams
of Melosira (a type of ice algae) extending several feet below the
ice bottom, like big strands of seaweed. The second bloom occurs a
little later and is by phytoplankton in the water column. And can
there be too much? Yes! There often is too much in the water column
for the consumers there to eat (the consumers are zooplankton like
copepods). So the bloom will settle deeper in the water column, eventually
reaching the benthos and the animals that live down there. This is
especially true in the Chukchi Sea, where we spent the first portion
of the cruise and where there is a very rich and abundant benthic
community because so much food falls down from the water column."
Tonight the CTD crew will be back in action taking
measurements across the Beaufort shelfbreak. This weekend we hope
to finish off the mooring deployments. So far the weather forecast
looks good, but we still all have our fingers crossed.
Tomorrow night we we will have a bit of a break from the routine -- it's casino night!
There will be all sorts of high stakes entertainment, and plenty of (fake) money will be
changing hands. Be sure to check the website tomorrow for
some humorous photos.