Drones to study hurricanes

Globalhawk

Some of the most exciting film associated with weather research are the flights of "Hurricane Hunter" aircraft flying into hurricanes. Watching these planes and their occupants get bounced around inside a hurricane is always dramatic. Now NASA is taking another approach to studying storms from the air: using unmanned drone aircraft like Global Hawk. These 44-foot long, 25,000-pound unmanned aircraft have one big advantage over manned aircraft: no crew to grow weary. Gobal Hawk drones can climb higher than 65,000 feet and stay there for approximately 28 hours gathering hurricane data. The hope is that the data these drones can collect will help improve hurricane forecasting, a definite boon to the voyager.

According to NASA, the key part of the Global Hawk mission, dubbed Hurricane and Severe Storm Sentinel (HS3), will be improving the ability to predict the intensity of hurricanes. While hurricane track prediction has improved in recent decades, improvements in hurricane intensity prediction have lagged, primarily as a result of a poor understanding of the processes involved in storm intensity change. HS3 is a five-year mission targeted to enhance our understanding of the processes that underlie hurricane intensity change in the Atlantic Ocean basin. HS3 will determine the extent to which either the environment or processes internal to the storm are key to intensity change.

Two NASA Global Hawk aircraft will operate from NASA's Wallops Island Flight Facility in Virginia from August through early October. NASA's Global Hawk drones were first used in 2010 for the Genesis and Rapid Intensification Processes (GRIP) hurricane mission, with a first successful flight into Hurricane Earl on Sept. 2, 2010.

"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. HS3 seeks to improve our understanding of these processes by taking advantage of the surveillance capabilities of the Global Hawk along with measurements from a suite of advanced instruments," said Scott Braun, HS3 mission principal investigator and research meteorologist at NASA's Goddard Space Flight Center in Greenbelt, Md.

The instruments to be mounted in the Global Hawk aircraft that will examine the environment of the storms include the scanning High-resolution Interferometer Sounder (S-HIS), the Advanced Vertical Atmospheric Profiling System (AVAPS) also known as dropsondes, and the Cloud Physics Lidar (CPL). The Tropospheric Wind Lidar Technology Experiment (TWiLiTE) Doppler wind lidar will likely fly in the 2013 mission.

Another set of instruments will fly on the Global Hawk focusing on the inner region of the storms. Those instruments include the High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) conically scanning Doppler radar, the Hurricane Imaging Radiometer (HIRAD) multi-frequency interferometric radiometer, and the High-Altitude Monolithic Microwave Integrated Circuit Sounding Radiometer (HAMSR) microwave sounder. Most of these instruments represent advanced technology developed by NASA, that in some cases are precursors to future satellite sensors.

NASA's Science Mission Directorate Global Hawk aircraft will deploy to Wallops Flight Facility from their home base at NASA's Dryden Flight Research Center on Edwards Air Force Base, Calif.

"HS3 marks the first time that NASA's Global Hawks will deploy away from Dryden for a mission, potentially marking the beginning of an era in which they are operated regularly from Wallops," said Paul Newman, atmospheric scientist at NASA Goddard and deputy principal investigator on the HS3 mission.

What about the famed manned Hurricane Hunter aircraft? The National Oceanic and Atmospheric Administration (NOAA) still has a Hurricane Hunter unit based at McDill Air Force Base in Florida that flies P-3 Orion and Gulfstream IV aircraft into storms. The Air Force also has a unit, the 53rd Weather Reconnaisance Squadron based at Keesler  Air Force Base in Biloxi, Miss., that also flies manned aircraft flights into storms.

By Ocean Navigator