Edge of the Arctic Shelf

Anchors away!
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."