HR: 0800h
AN: AE21A-0975    [Abstracts]
TI: Narrow Bipolar Events, Strong VHF Pulses and Their Relationship to Thumderstorm Evolution
AU: * Suszcynsky, D M
EM: dsuszcynsky@lanl.gov
AF: Los Alamos National Laboratory, Space & Remote Sensing Sciences Group MS D436, Los Alamos, NM 87506
AU: Wiens, K C
AE21A-0975 AF: Los Alamos National Laboratory, Space & Remote Sensing Sciences Group MS D436, Los Alamos, NM 87506
AU: Shao, X
EM: xshao@lanl.gov
AF: Los Alamos National Laboratory, Space & Remote Sensing Sciences Group MS D436, Los Alamos, NM 87506
AB: FORTE and GPS satellite studies have shown that satellite-based VHF lightning sensors are particularly sensitive to a ubiquitous and unique type of strong in-cloud RF lightning pulse that is sometimes accompanied by a Narrow Bipolar Event (NBE). The physical relationship between NBEs and their impulsive VHF counterparts is not clear. Presumably, the strong VHF pulses are associated with an initiating breakdown process while the NBE emissions are linked to subsequent large-scale charge flow. Strong VHF pulses may or may not lead to NBE production (significant charge relaxation) but a NBE is always accompanied by a strong VHF pulse. More recent and ongoing work has focused on establishing the meteorological context of both NBEs and strong VHF pulses, particularly as they relate to satellite-based VHF lightning monitoring. Of particular interest is the possibility of using NBE/Strong VHF pulse occurrence as a tool for remotely detecting severe weather. This paper presents a preliminary investigation into the temporal and spatial relationship between NBEs and GPS-satellite-observed strong VHF pulses, particularly as they relate to thunderstorm development and the occurrence of severe weather. Strong VHF pulse data from lightning-sensitive VHF receivers aboard the GPS satellite constellation will be compared to NBE data collected by the ground-based Los Alamos Sferic Array (LASA) located in Florida and the Great Plains, NEXRAD radar scans and severe weather reports in order to evaluate their spatial and temporal occurrence with respect to thunderstorm activity (also see K. Wiens paper in this session). Emphasis will be placed on identifying precursor indicators of severe weather via flash rate 'jump' signatures and on interpreting the observational differences between NBEs and strong VHF pulses in the context of thunderstorm evolution.
DE: 3304 Atmospheric electricity
DE: 3324 Lightning
DE: 3394 Instruments and techniques
SC: Atmospheric and Space Electricity [AE]
MN: Fall Meeting 2005