These severe storm sentinels will investigate the processes that underlie hurricane formation and intensity change. NASA’s Jet Propulsion Laboratory in Pasadena, California, will join several other NASA centers and numerous federal and university partners in the missions.
So far both the Atlantic and Pacific hurricane seasons are predicted to the normal, meaning just several hurricanes, according to the National Oceanic and Atmospheric Administration.
The automatically-flown Global Hawk aircraft are well-suited for hurricane investigations, said NASA. They can overfly hurricanes at altitudes greater than 18,300 meters (60,000 feet), and fly up to 28 hours at a time — something piloted aircraft would find nearly impossible to do. Global Hawks were used in the agency’s 2010 Genesis and Rapid Intensification Processes hurricane mission and the Global Hawk Pacific environmental science mission. The Global Hawks will fly from NASA’s Wallops Flight Facility in Virginia and are based at NASA’s Dryden Flight Research Center on Edwards Air Force Base, California.
“Hurricane intensity can be very hard to predict because of an insufficient understanding of how clouds and wind patterns within a storm interact with the storm’s environment,” said
Scott Braun, the mission principal investigator and research meteorologist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. The unmanned aircraft missions seek to improve understanding of these processes by taking advantage of the surveillance capabilities of the Global Hawk along with measurements from a suite of advanced instruments, he added.
“One aircraft will sample the environment of storms while the other will measure eyewall and rainband winds and precipitation,” Braun continued. The study will examine the large-scale environment in which tropical storms form and move through and how that environment affects the inner workings of the storms, he said.
The aircraft will address the controversial role of the hot, dry and dusty Saharan air layer in tropical storm formation and intensification. Past studies have suggested the layer can both favor and suppress intensification. In addition, the aircraft will examine the extent to which deep convection in the inner-core region of storms is a key driver of intensity change or just a response to storms finding favorable sources of energy, NASA said.
The crafts will carry sophisticated instruments to measure water vapor and heat radiation in the inner regions of storms. One device will use microwaves. Some of these devices are expected to be used in future NASA space missions.
The instrument operates at microwave frequencies that can penetrate clouds, enabling it to determine temperature, humidity and cloud structure under all weather conditions, said NASA, adding that this capability is critical for studying atmospheric processes associated with bad weather, like the conditions present during hurricanes.