HR: 09:45h
AN: AE11B-06    [Abstracts]
TI: Transient Currents in the Global Electric Circuit
AU: * Marshall, T C
EM: marshall@olemiss.edu
AF: Department of Physics and Astronomy, University of Mississippi PO Box 1848, University, MS 38677-1848 United States
AU: Stolzenburg, M
EM: mstolzen@phy.olemiss.edu
AF: Department of Physics and Astronomy, University of Mississippi PO Box 1848, University, MS 38677-1848 United States
AU: Mareev, E A
EM: mareev@appl.sci-nnov.ru
AF: Institute of Applied Physics, Russian Academy of Science 46 Ulyanov Str, Nizhny Novgorod, 603950 Russian Federation
AU: Davydenko, S S
EM: davyd@appl.sci-nnov.ru
AF: Institute of Applied Physics, Russian Academy of Science 46 Ulyanov Str, Nizhny Novgorod, 603950 Russian Federation
AB: Since the time of C.T.R. Wilson, thunderstorms have been viewed as the generators in the Earth's global electric circuit. Vonnegut, Moore, et al. [1966] showed that there were substantial electric fields above thunderstorm cores, which they attributed to holes in the cloud-top screening layer. These above-cloud fields are assumed to be important in driving currents between the cloud top and ionosphere in the global electric circuit. Vonnegut, Moore, et al. also showed that lightning flashes provide transient changes in the above-cloud electric field. We will present balloon measurements of electric field inside and above small, mountain thunderstorms and large, mesoscale convective systems. These measurements indicate that lightning transients sometimes enhance the above-cloud electric field magnitude, regardless of the presence or absence of a hole in the upper screening layer. We will also describe results from a one-dimensional model used to investigate the possibility that the above-cloud transient fields also play a significant role in the global circuit. Reference: Vonnegut, B., C. B. Moore, R. P. Espinola, and H. H. Blau, Jr., Electric potential gradients above thunderstorms, J. Atmos. Sci., 23, 764-770, 1966.
DE: 2427 Ionosphere/atmosphere interactions (0335)
DE: 3304 Atmospheric electricity
DE: 3324 Lightning
SC: Atmospheric and Space Electricity [AE]
MN: 2005 Joint Assembly