On October 28, 2015, a group of scientists from Otago University's Department of Physics observed the last sunset of the year in Antarctica to research why Antarctic sea ice has reached record heights for the past three years while Arctic ice is shrinking. They used heated water to melt through 2.3 meters of ice and deployed 16 instruments to measure the ice, hypothesizing that supercooled water below the ice keeps it cold, in an effort to understand why the ice behavior contradicts expectations of thinning under global warming.