Students of oceanographer Fiamma Straneo retrieve a CTD rosette from waters off San Diego during a June 1 instructional cruise aboard Scripps Institution of Oceanography at UC San Diego research vessel Robert Gordon Sproul. The cruise gave students the opportunity to test the performance of handheld CTDs they created themselves and compare it to standard CTD units such as the one seen in the photo.
CTD stands for conductivity-temperature-depth and rosettes are commonly used by marine scientists to provide that data. They contain canisters that open and collect seawater at specific ocean depths. Researchers then retrieve the rosettes and analyze the water on board. The students are experimenting with low-cost alternatives to traditional CTDs, which cost roughly $15,000 to $25,000 fully outfitted.