April 1, 2012 Moorings

Speed 1.8 knots
Course 290°
Location Larsen A (-64.897605, -60.77175167)
Depth 495 meters

Besides just looking at organisms and mud, scientists are also interested in the water itself. In order to study the water and how the water carries sediment, Bruce Huber from Lamont-Doherty Earth Observatory at Columbia University, Amy Leventer from Colgate University, and their students have been building and assembling moorings.

Moorings

The moorings are dropped to the bottom of the ocean and rise about 115 meters off the sea floor. In order to keep them on the sea floor, several weights are attached to the bottom of the mooring.

Buzz Scott and the bottom weights on the mooring (photo taken by Caroline Lavoie)

On each mooring, there are three sediment traps, which are large yellow fiberglass funnels. At the bottom of the funnel is a plastic tube that collects all of the sediment that gathers in the funnel. In a couple years, another boat will come by and pick up these moorings and the scientists will look at how much and what type of sediment has accumulated. The three traps are attached at different depths to give more information about water currents at different levels.

Buzz Scott (left) and Jason Theis (right) with one of the sediment traps

The moorings also contain several instruments that measure water conditions such as temperature, pressure, salinity and currents.

Buzz Scott (left) and Jason Theis (right) attaching a temperature-pressure sensor to the mooring (photo taken by Caroline Lavoie)

This is a long process and it usually takes about t hours to assemble the mooring. Each piece has to be attached and then lowered into the water. You never know what you might see while on the deck. Today, this inquisitive minke whale showed up to check out what was going on.

Minke whale during mooring installation

The last part of the mooring that goes in the water is the floats. The mooring is weighted down at the bottom, but these floats keep the mooring upright in the water so the instruments are all at the correct depths.

Buzz Scott and the floats of the mooring

The mooring installation requires a lot of concentration and hard work. This couldn't be accomplished without the guidance and oversight of the scientists involved. They play an integral role in making sure everything goes smoothly and the moorings are correctly installed.