HR: 11:05h
AN: AE42A-04    [Abstracts]
TI: IR Temperature Characteristics of a Prolific TLE Producing Storm in South America Observed During a Sprite Campaign in Brazil
AU: * São Sabbas, F
EM: saosabbas@dae.inpe.br
AF: INPE, Av. dos Astronautas 1758, São José dos Campos, 12245-970, Brazil
AU: Rampinelli, V T
EM: viniciusrampinelli@yahoo.com.br
AF: INPE, Av. dos Astronautas 1758, São José dos Campos, 12245-970, Brazil
AU: Pautet, P
EM: dominiquepautet@gmail.com
AF: INPE, Av. dos Astronautas 1758, São José dos Campos, 12245-970, Brazil
AU: Taylor, M
EM: mtaylor@cc.usu.edu
AF: Utah State University, CASS SER-22, Logan, 81322, United States
AU: Bailey, M
EM: mattbailey@cc.usu.edu
AF: Utah State University, CASS SER-22, Logan, 81322, United States
AU: Solorzano, N N
EM: nataliansolo@gmail.com
AF: Digipen Institute of Technology, 5001 150th Ave, Redmond, 98052, United States
AU: Thomas, J N
EM: jnt@u.washington.edu
AF: United States and National Geomagnetism Program, USGS, po box 25046 MS-966, Denver, 80225, United States
AU: Thomas, J N
EM: jnt@u.washington.edu
AF: University of Washington, box 35310, Seattle, 98195, United States
AU: Cummer, S A
EM: cummer@ee.duke.edu
AF: Duke University, box 90291, Durham, 27708, United States
AU: Holzworth, R H
EM: bobholz@ess.washignton.edu
AF: University of Washington, box 35310, Seattle, 98195, United States
AU: Pinto, O
EM: osmar@dge.inpe.br
AF: INPE, Av. dos Astronautas 1758, São José dos Campos, 12245-970, Brazil
AU: Schuch, N J
EM: njschuch@lacesm.ufsm.br
AF: INPE, Av. dos Astronautas 1758, São José dos Campos, 12245-970, Brazil
AB: A total of 445 Transient Luminous Events, TLEs, were observed above a Mesoscale Convective System, MCS, over Argentina on the night of 22-23 February, 2006, during the third sprite campaign ever conduced in Brazil. We investigated the temporal-spatial evolution of the cloudtop temperature of the MCS based on satellite infrared imagery and their relationship with cloud-to-ground lightning and TLE activity. We used the same methodology São Sabbas and Sentman [2003] applied to a US sprite producing MCS and compared the results. The Argentinean thunderstorm was a mesoscale system with very different characteristics than regular TLE producing MCSs. It originated from the merge of several convective storms that remained as collection of "isolated" convective regions (Tc < -52o C) under a common cloud cover (Tc < - 32o C) throughout its lifetime. We started to record TLEs at least 3 hr before the system could be classified as an MCS and the temperature of the cloud cover, ~ -52o C, was at ~15 o C higher than of the US MCS. Most of the lightning tended to occur at the borders of the convective cores instead of occurring at the cores themselves. Another difference was that while the US MCS produced sprites only in the back region, the Argentina system produced sprites/TLEs both in the back and front regions. The sprites occurred above regions with ~ -40o C in the beginning of the observations and with ~ -58o C at the end. This also differs from the US case study, in which all sprites happened above regions with ~ -70o C and ~ -64o C. The main similarity was that in the growth phase the lightning occurrence rate increased in association with regions with decreasing cloudtop temperatures (~ -50o C to ~ -58o C ), until a maximum rate was reached in association with minimum temperatures, however in the US MCS the temperatures involved were lower (~ -64o C to ~ -70o C). Another interesting similarly between the US and Argentina MCSs is that both moved towards Northeast at ~85 km/h and ~45 km/h, respectively. The overall development of this system was very complex and highly structured, which may have contribute in unpredicted ways to the exceptional TLE activity documented.
DE: 3324 Lightning
DE: 3344 Paleoclimatology (0473, 4900)
DE: 7823 Ionization processes (2423)
SC: Atmospheric and Space Electricity [AE]
MN: 2007 Fall Meeting