Expedition log by Video Lab Research Technician Larissa Lemon

There is a moment before every deployment when the mood shifts from anticipation to something more palpable. The equipment is staged to precision. Each frame, line, and sensor represents years of planning and preparation. At sea, the coordinated choreography of teams and tech makes the deployments a success. These collaborations between scientists and engineers, brought to life by marine operations crew, allow MBARI to make such an impact on deep-sea science and technology.

Following the months of preparation on shore, scientists spend hours on deck mapping just how each section of the Sedimentation Event Sensor (SES) mooring should be laid out, in what order, and how the pieces all connect. Floats, lines, and sensors are moved to their precise positions with minor adjustments made along the way to ensure the marine operations team can easily and safely get the equipment in the water. Engineers scrutinize code, ping sensors, and verify data streams—all to provide a small signal of reassurance against the uncertainty of leaving equipment in waters two miles (3,300 meters) deep for half a year.

The SES helps MBARI scientists monitor carbon transport to the abyssal seafloor. Tiny bits of organic material sink through a sampling funnel, landing on a slide above a camera. When the camera detects a rapid increase in the amount of particles sinking over a certain period of time, it sends a message to another sediment funnel system, the trigger trap, 50 meters (164 feet) above to begin collecting samples of sinking particles once per hour.

The SES is stationed above the seafloor, installed on a mooring approximately 300 meters (almost 1,000 feet) above the bottom. To maintain proper line tension, the system uses a series of floats to provide about 800 pounds (363 kilograms) of buoyancy opposing a 600-pound (272-kilogram) ballast weight at the bottom. 

In the end, collecting data at depth relies on the practiced coordination of the people who bring technology to the deep sea. Teamwork among scientists, engineers, and ship crew turns operational complexity into a graceful routine, while adapting each deployment to the unique quirks of equipment and shifting conditions of the ocean. It’s a melody that repeats itself again and again, never identical, always refined—science, engineering, and operations in constant rhythm.