Adrienne Heim, August 27, 2007


NOAA Teacher at Sea
Adrienne Heim
Onboard NOAA Ship Albatross IV
August 7 – September 2, 2007

The CTD, recording information at depth

The CTD, recording information at depth

Mission: Sea Scallop Survey
Geographic Region: Northeast U.S.
Date: August 27, 2007

Science and Technology Log: CTD Casts
Immediately following the fire and abandon ship drills, we proceeded to have a debriefing regarding appropriate and professional behaviors, as well as, receiving information regarding shift schedules, meals, work expectations, etc. Our Chief Scientist, Victor Nordahl, informed us of the various duties and responsibilities each of us would have during the Sea Scallop Survey. I was paired with another volunteer, Shawn, to help with the measuring of the sea scallops once they were sorted and weighed. I was also assigned the role of performing CTD casts and collecting data from the inclinometer.CTD casts are performed at every third station. The acronym stands for conductivity, temperature, and depth. It is a hefty contraption that is hooked onto a cable and sent down, a vertical cast, into the water. Basically, while the CTD is sent down vertically, it records the temperature, depth, salinity, and pressure. The saltier the water, the more conductivity is generated. The cast first soaks for about one-two minutes at the surface of the water to record the salinity. It is then sent down, stops about 5-10 meters before reaching the bottom of the ocean floor and then is hauled back. Recording this data is essential for scientists, especially while conducting a Sea Scallop Survey; because the CTD casts helps to associate water temperature and salinity with sea scallop abundance. Scientists record the data to view it later and assess the casts with the other data collected from the work stations.
Computers and cameras recording information from the CTD

Computers and cameras recording information from the CTD

The winch at the back of the ship

The winch at the back of the ship

Communicating with the winch operator

Communicating with the winch operator