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EPOCH: East Pacific Origins and Characteristics of Hurricanes

What:   East Pacific Origins and Characteristics of Hurricanes (EPOCH) Project

When:   1-30 August 2017

Where: NASA Armstrong Flight Research Center, Edwards Air Force Base, California

Why:    This project will investigate how storms develop into hurricanes and intensify. 


This project conducted up to six 24-hour science flights using the Global Hawk unmanned aircraft. Three of the flights were supported through a partnership with the NOAA UAS Program. The aircraft flew over developing tropical cyclones and collected data using 3 on-board instruments (EXRAD, HAMSR, and AVAPS).

EXRAD (ER-2 X-band Radar) is a high-power airborne Doppler radar developed by NASA Goddard Space Flight Center that flew for the first time on the Global Hawk. HAMSR (High Altitude Monolithic Microwave Integrated Circuit Sounding Radiometer) is a microwave atmospheric sounder designed and built by the Jet Propulsion Laboratory. AVAPS (Advanced Vertical Atmospheric Profiling System) collects high vertical resolution in situ measurements of temperature, pressure, relative humidity, wind speed and direction through the deployment of dropsondes. It was jointly developed by NOAA and NCAR.

The Global Hawk unmanned aircraft was developed for the U.S. Air Force by Northrop Grumman and is ideally suited for high altitude, long duration Earth science flights. The ability of the Global Hawk to autonomously fly long distances, remain aloft for extended periods of time and carry large payloads brings a new capability to the science community for measuring, monitoring, and observing remote locations of Earth not feasible or practical with piloted aircraft or space satellites. NASA Armstrong Flight Research Center operates two Global Hawk aircraft for scientific research.

Principal Investigator: Amber Emory, PhD (

Project Manager: Alfred Fordan (