NASA's Global Hawk in 2014 traveled to the middle of the Atlantic and flew over Hurricane Edouard. Remote sensing nstruments on the plane measured temperature, relative humidity, wind speed, wind direction as well as other data. Along with measurements from the aircraft, NASA scientists also collected data from dropsondes that parachuted down through the hurricane.
The swirling nature of hurricane clouds are a familiar sight in satellite imagery, but in order to better understand these storms, scientists need to look inside them. In 2014, NASA's remotely piloted Global Hawk aircraft flew over Hurricane Edouard in the Atlantic Ocean to help better understand what makes hurricanes intensify.
During the 24-hour flight, a sounder instrument measured the relative humidity of the storm from above, where the cloud cover was thin. Where clouds were too thick, including around the eye of the hurricane, the Global Hawk released dropsondes – foot-long sensors that dropped from the aircraft down through the storm to the ocean's surface – sending back data on humidity, temperature and wind the whole way down. Warm, moist air helps to give hurricanes their strength, and near the eye, the red colors show high humidity powering the storm.
Scientists use these and other data collected from these flights to better understand the environmental signals inside and outside of the hurricanes. They want to better understand the signals that lead to rapid intensification where wind speeds dramatically increase in a 24-hour period – vital information for anyone in the storm's path.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 18.104.22.168.0