Archive for April 8, 2019

After sunrise we did more surveying to find a good location for an array of 48 drifters. We deployed this sequence of drifters along a transect to look at the flow of water at a series of depths. The drifters have different length cables so that the drogues (also known as “holey socks” because of their appearances), which pull them along, will be following the water at different depths. These drifters are special because they are mostly biodegradable, using canvas for the drogues and copper balls for floats instead of plastic. Even though studying the ocean is important, that doesn’t mean scientists get a free pass on ocean plastic pollution! And, of course, we do retrieve some of the things we deploy! It took a big team effort to deploy all of the drifters in a short time! Nearly all of the scientific staff and many crew members participated in this! This drifter experiment was designed by Irina Rypina and Ben Hodges at WHOI.

Surveying with the underway CTD at sunrise

drifter components on deck waiting to be assembled – copper float, canvas drogue, and metal cable to connect them, plus the GPS unit on top of each buoy.

Mat and Daniel lower a surface drifter into the water.

Four drifters in the water before their drogues sink

Benjamin and Noemi get ready to deploy a drifter that will track the flow at 100 meters!

Today is a very busy day with a lot of deployments of different types of equipment. Before daybreak we deployed a wirewalker, an instrument that moves with the currents while profiling up and down to observe the upper water column. Its up and down motion is powered by the waves! It measures the flow velocity as well as the temperature, salinity, and biological variables. We hope that this will complement our many surveys by showing us how the properties of the flow evolve as we follow the front.

Deploying the wirewalker