A saildrone is a “wind-propelled vehicle that looks a lot like a sailboat”, says Julia Paxton, director of mission management at Saildrone. The drones – which come in a variety of sizes, either 23ft (7m), 33ft (10m) or 65ft (20m) long – combine wind propulsion with solar-powered meteorological and oceanographic sensors that allow scientists to measure the track, or path, a hurricane it taking along with changes in its intensity over time.
The saildrones can also capture data beneath the waves and analyse ocean currents. This helps “create a complete [picture] of the air and water column, from 30,000ft (9,144m) above [sea level] to several 1,000ft (300m) below the surface”, says Paxton.
Saildrone’s mission is “not about predicting hurricanes this season”, says Paxton. “It’s about studying why and how hurricanes intensify so that in the future we can improve hurricane modelling.”
Hurricanes form over warm water surfaces. As the ocean water evaporates and rises as warm air, it forms an area of low pressure underneath. This results in more air rushing in, which rises and cools and forms clouds and thunderstorms, which in turn release water droplets. This leads to the evaporation of even more water, fueling the storm. When wind speeds reach 74mph (119km/h) within such a storm, it is classified as a hurricane.