HR: 1340h
AN: AE23A-0846    [Abstracts]
TI: Runaway breakdown and thunderstorm and lightning electric fields
AU: * Dwyer, J R
EM: jdwyer@fit.edu
AF: Florida Institute of Technology, Dept. of Physics and Space Sciences 150 W. University Blvd., Melbourne, FL 32901 United States
AU: Rassoul, H K
EM: rassoul@fit.edu
AF: Florida Institute of Technology, Dept. of Physics and Space Sciences 150 W. University Blvd., Melbourne, FL 32901 United States
AU: Al-Dayeh, M
EM: maldayeh@fit.edu
AF: Florida Institute of Technology, Dept. of Physics and Space Sciences 150 W. University Blvd., Melbourne, FL 32901 United States
AU: Caraway, L
EM: caraway78@yahoo.com
AF: Florida Institute of Technology, Dept. of Physics and Space Sciences 150 W. University Blvd., Melbourne, FL 32901 United States
AU: Wright, B
EM: bwright@fit.edu
AF: Florida Institute of Technology, Dept. of Physics and Space Sciences 150 W. University Blvd., Melbourne, FL 32901 United States
AU: Chrest, A
EM: achrest@fit.edu
AF: Florida Institute of Technology, Dept. of Physics and Space Sciences 150 W. University Blvd., Melbourne, FL 32901 United States
AU: Uman, M A
EM: uman@ece.ufl.edu
AF: University of Florida, Department of Electrical and Computer Engineering, Gainesville, FL 32611 United States
AU: Rakov, V A
EM: rakov@ece.ufl.edu
AF: University of Florida, Department of Electrical and Computer Engineering, Gainesville, FL 32611 United States
AU: Rambo, K J
EM: rambo@tec.ufl.edu
AF: University of Florida, Department of Electrical and Computer Engineering, Gainesville, FL 32611 United States
AU: Jordan, D M
EM: jordan@ece.ufl.edu
AF: University of Florida, Department of Electrical and Computer Engineering, Gainesville, FL 32611 United States
AU: Jerauld, J
EM: jjerauld@ufl.edu
AF: University of Florida, Department of Electrical and Computer Engineering, Gainesville, FL 32611 United States
AB: Recent measurements of x-ray emission made at the International Center for Lightning Research and Testing (ICLRT) at Camp Blanding, FL, have shown that runaway breakdown is likely a common property of lightning. However, the intensity, source location and energy spectrum of this emission does not appear to be consistent with the relativistic runaway electron avalanche (RREA) model, developed by Gurevich et al. (1992). An alternative model is the so-called cold runaway electron model. In this model, the high energy tail of the bulk free-electron population runs away and can be accelerated to relativistic energies. However, this model requires an electric field, presumably at the leader tip, much larger than the conventional breakdown field. On the other hand, recent observations of gamma-ray emission from thunderstorms appear to be consistent with the RREA model. In some cases, calculations show that the intensity of runaway electrons may be sufficiently large to limit the electric field that can be achieved inside thunderstorms. In this presentation, results of a new Monte Carlo simulation of runaway breakdown will be presented, a comparison with the x-ray observations of lightning will be made, and the implications for thunderstorm and lightning electric fields will be discussed.
DE: 3324 Lightning
DE: 3329 Mesoscale meteorology
DE: 3359 Radiative processes
DE: 3367 Theoretical modeling
DE: 3304 Atmospheric electricity
SC: Atmospheric and Space Electricity [AE]
MN: 2004 AGU Fall Meeting