HR: 1340h
AN: AE33A-0189    [Abstracts]
TI: Electric field Change Characteristics of Strong and Weak Optical Pulses from the Altus Cumulus Electrification Study (ACES)
AU: * Mach, D M
EM: douglas.mach@msfc.nasa.gov
AF: University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, AL 35899 United States
AU: Blakeslee, R J
EM: richard.blakeslee@msfc.nasa.gov
AF: NASA Marshall Space Flight Center, GEORGE C. MARSHALL SPACE FLIGHT CENTER, Huntsville, AL 35812 United States
AB: We examine the properties of the electric field changes associated with lightning generated optical pulses recorded as part of the Altus Cumulus Electrification Study (ACES). During ACES, we flew an unmanned aerial vehicle (UAV) around and over thunderstorms near the Western edge of the Florida Everglades. ACES was based out of Key West, Florida and operated during the month of August, 2002. During the nine data flights, we recorded time resolved optical and electrical pulses from the lightning generated in the thunderstorms. We have previously described the properties of lightning generated optical waveforms recorded during ACES and in that study, we found a class of optical pulses with lower amplitudes than what has been previously described. The possible sources of the weak optical pulses ranged from weak lightning near the top of the storms to artifacts due to our close proximity to the storm top (i.e., reflections off of the cloud tops from more distant lightning, or lightning from within the cloud partially obscured by local cloud elements). In this current study, we manually examine the electric field and optical pulse characteristics (risetimes, amplitudes, ratios, delays, etc.) of a subset of the 1172 weak and 3141 strong pulses to see if the waveforms can provide more information as to the source of the weak pulses.
DE: 3324 Lightning
DE: 3360 Remote sensing
DE: 3394 Instruments and techniques
DE: 3304 Atmospheric electricity
SC: Atmospheric and Space Electricity [AE]
MN: 2004 AGU Fall Meeting