HR: 08:20h
AN: AE51A-02    [PDF]
TI: Investigating sprite energetics over Brazil in association with small/frontal storms
AU: * Taylor, M J
EM: mtaylor@cc.usu.edu
AF: Center for Atmospheric and Space Sciences, Utah State University, Logan, UT 84322 United States
AU: Pautet, P D
EM: pautet@cc.usu.edu
AF: Center for Atmospheric and Space Sciences, Utah State University, Logan, UT 84322 United States
AU: Bailey, M
EM: mattbailey@cc.usu.edu
AF: Center for Atmospheric and Space Sciences, Utah State University, Logan, UT 84322 United States
AU: SaoSabbas, F
AF: INPE, INPE, Sao Jose dos Campos, SP 00000 Brazil
AU: Pinto, O
AF: INPE, INPE, Sao Jose dos Campos, SP 00000 Brazil
AU: Holzworth, R
AF: University of Washington, University of Washington, Seattle, WA 00000 United States
AU: Sato, M
AF: Tohoku University, Tohoku University, Sendai, 00000 Japan
AB: As part of the sprites 2002 balloon campaign, a suite of intensified CCD cameras were used to obtain novel data on the occurrence and properties of sprites over south eastern Brazil. Measurements were made from a field station at Cachoeira Paulista (23S, 45W), and from an Embraer aircraft both operated by the INPE (Instituto Nacional de Pesquisas Espaciais). A total of eighteen transient optical events were recorded, sixteen of which exhibited vertical structures typically associated with sprites, while the other two were disc-like events, characteristic of sprite halos or elves. Coordinated measurements by the ELAT Brazilian lightning network show that all but three of these transient events were associated with positive lightning discharges generated by relatively small thunderstorms, that were induced primarily in association with the passage of strong cold fronts. Furthermore, simultaneous ELF data obtained from Syowa Station, Antarctica and Onagawa, Japan, indicate that the charge moments associated with these events ranged from 240 to 1500 C.km with a predominance of 400-600 C.km. These observations provide the first quantitative measurements of sprites over Brazil. Although our data acquisition was limited by prevailing weather conditions, the results indicate that sprites occur relatively frequently over south eastern Brazil during the fall and spring time periods, mostly in association with rapidly developing small storms or with frontal systems.
DE: 0342 Middle atmosphere--energy deposition
DE: 3304 Atmospheric electricity
DE: 3324 Lightning
DE: 3332 Mesospheric dynamics
SC: Atmospheric and Space Electricity [AE]
MN: 2003 Fall Meeting