A pair of converted US military drones are NASA’s newest tools for tracking hurricanes and tropical storms, with the aim of improving forecasters’ ability to predict them.
Originally built for military reconnaissance missions around the world, they are the size of large commercial jets and are flown remotely from a Wallops Island, a NASA base on Virginia’s coast.
The drones are capable of flying for 30 hours at an altitude of 21,000m, or twice the height of a passenger plane.
The two Global Hawks began operating as drones for the US space agency last year as part of a three-year-long project called HS3 — which stands for the Hurricane and Severe Storm Sentinel.
“It opens a window into a storm we did not have before,” said Scott Braun, a research meteorologist on the project. “Before, we had short snap shots of individual storms at various times.”
Until now, the stand-bys for monitoring storms have been piloted weather planes and satellites, Braun said.
“By being able to view a storm continuously over a 20-hour period, you have a longer window to capture it,” he added. “This experiment will allow a better understanding of the processes that govern the intensification in the formation of storms.”
Even though scientists have been able to make great leaps in projecting the paths of hurricanes in recent years, their ability to predict the power and severity of storms has improved very little.
Better forecasts would help authorities make life and death decisions, like whether and when to evacuate people, more swiftly.
The drones have two chief missions: determine the role of thunderstorms and rain in the intensification of storms, and study the influence of the Saharan Air Layer in the intensity of cyclones.
Each of the planes is equipped with a laser for studying the structure of the clouds, a microwave system to probe the heart of hurricanes, GPS systems and radar, among other things.
Their precision instruments measure temperature, humidity and atmospheric pressure several times per second. The drones send the data via satellite to the Wallops base and then to the US National Hurricane Center, where they can be distributed to weather forecasters across the US in near real-time.