DISCO Diver

WHOI chemist Colleen Hansel swims over a reef off the southern coast of Cuba with DISCO (diver-operated underwater analyzer of superoxide), a new sensor she developed with chemist Scott Wankel, research engineer Jason Kapit, and engineer Kevin Manganini, with funding from the Schmidt Marine Technology Partners. DISCO measures the concentration of short-lived molecules in the water produced by coral and their algal symbionts, which in low concentrations can be benefical to living coral. As water warms, however, the algae produce more superoxide—a highly reactive form of oxygen—causing the coral to expel their algae and turning the coral a ghostly white, a phenomena known as bleaching that will kill the coral if conditions do not change. (Photo by Ashlee Lillis, Woods Hole Oceanographic Institution)