The Deep Cast Chronicles: Colder, Darker, Denser…Smaller

If there’s one thing you can count on as a scientist aboard a research expedition at sea, it is the infamous “Deep Cast”. This is a CTD cast that goes deeper than any other. The Deep Cast is a big deal logistically because it takes over an hour to get to its final depth (4,000m at 60m/min), is interesting scientifically because it samples very old water, and is coveted by all on board because it is the shrinking Styrofoam cast…

Everyone on board partakes in the ritual of decorating anything made of Styrofoam in preparation for the Deep Cast. Our devoted resident marine technician Caitlyn offered her battalion of rainbow sharpies (72 strong!) for us to use, and we got to work. 

Jamee Adams (Diaz lab), Anya Stajner (Decima lab), Rob Lampe (Allen lab), Clay McClure (Bowman lab), and Dante Capone (Decima lab) decorating Styrofoam and staying healthy.
Clay McLure, Dante Capone, and Dante’s creation.

Then, we strapped our creations to the CTD wrapped in layers of mesh bags, and sent the whole package down to 4,000 meters. It took over 2 hours for the CTD to travel down, down, down through layers of cold, dense, dark water, and back up to the surface.

Professors Lihini Aluwihare and Kathy Barbeau packing the cups.
Ralph Torres (Aluwihare lab) securing the mesh bags.
Marine technician Caitlyn sending the CTD down to 4,000 meters.

When the CTD came back to the surface with precious North Pacific deep water, the oldest on Earth, everything had changed. Styrofoam heads were deformed and dense, cups were shrunken, and drawings had taken on a more detailed appearance. The increase in pressure down to 4,000 meters forced the air out of the Styrofoam, and caused each piece to shrink. 

Post Deep Cast Styrofoam. 
A Styrofoam shoutout to California Current Ecosystem Long Term Ecological Research (CCE LTER)!

Aside from our treasured oceanographic samples, anyone who made a Styrofoam creation has a more personal souvenir to take home and gift to friends, family, and loved ones, or to keep for themselves as a reminder of this epic adventure. 

A family of cups.

-Jamee Adams (Diaz lab)