@MastersThesis{Silva:2014:CoCaVi,
author = "Silva, Larissa Antunes da",
title = "Compara{\c{c}}{\~a}o de caracter{\'{\i}}sticas
vis{\'{\i}}veis de rel{\^a}mpagos nuvem-solo negativos para
diferentes dias de tempestade no sudeste do Brasil, observados por
uma rede de c{\^a}meras de alta velocidade",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2014",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2014-02-26",
keywords = "rel{\^a}mpagos, c{\^a}meras de alta velocidade, rede de
detec{\c{c}}{\~a}o de rel{\^a}mpagos, radar meteorol{\'o}gico,
Lightning, High-speed cameras, lightning locating systems, weather
radar.",
abstract = "O presente trabalho consiste em analisar algumas das
caracter{\'{\i}}sticas vis{\'{\i}}veis dos rel{\^a}mpagos
nuvem-solo negativos, separados por dia de tempestade. Os dados
foram obtidos utilizando uma rede de c{\^a}meras de alta
velocidade que fazem parte projeto RAMMER (Rede Automatizada
Multi-C{\^a}mera para o Monitoramento e Estudo de Raios). Muitos
estudos j{\'a} foram realizados utilizando c{\^a}meras de alta
velocidade, por{\'e}m a quantidade de c{\^a}meras observando a
mesma regi{\~a}o, utilizadas no projeto, foi in{\'e}dita e
proporcionou uma {\'a}rea de cobertura suficientemente grande
para aumentar o n{\'u}mero de rel{\^a}mpagos filmados a partir
da mesma tempestade. As observa{\c{c}}{\~o}es foram feitas
durante o ver{\~a}o de 2012/2013. Os cinco dias de tempestade que
tiverem o maior n{\'u}mero de rel{\^a}mpagos registrados foram
escolhidos para serem analisados e somaram 361 rel{\^a}mpagos
nuvem-solo negativos. Quando a an{\'a}lise foi feita por dia de
tempestade, foram encontradas diferen{\c{c}}as significativas, o
dia com menor amostra teve 47 rel{\^a}mpagos nuvem-solo negativos
registrados e o dia com maior amostra teve 117 rel{\^a}mpagos
nuvem-solo negativos. Al{\'e}m do tamanho da amostra, as
caracter{\'{\i}}sticas analisadas tamb{\'e}m apresentaram
diferen{\c{c}}as, a multiplicidade m{\'e}dia variou entre 2,8 e
5,1, a m{\'e}dia geom{\'e}trica dos intervalos entre as
descargas de retorno variou entre 47,8 ms e 69,5 ms e a
dura{\c{c}}{\~a}o variou entre 193,1 ms e 358,5 ms. O
M{\'e}todo de reamostragem Monte Carlo mostrou que o tamanho da
amostra n{\~a}o teve influ{\^e}ncia nas diferen{\c{c}}as
encontradas e a an{\'a}lise meteorol{\'o}gica mostrou que as
condi{\c{c}}{\~o}es de tempo foram as mesmas para todos os dias.
Para entender a varia{\c{c}}{\~a}o entre as
caracter{\'{\i}}sticas dos rel{\^a}mpagos nuvem-solo negativos,
foram utilizados os dados da refletividade de radar, na altura de
5 km e estimada a {\'a}rea de contorno 35 dBZ, que foi a
{\'a}rea considerada como uma estimativa da regi{\~a}o principal
de cargas negativas. ABSTRACT: The present study consists of
analyzing some of the visible characteristics of the negative
cloud-to-ground lightning, separated by thunderstorm day. The data
were obtained using a network of high-speed cameras that are part
of the project RAMMER (Network Automated Multi-Camera Monitoring
and Study of Lightning). There are many studies using high-speed
cameras, but the number of cameras observing the same region, as
used in this work, was not published in the literature, and
provided an area of coverage large enough to increase the number
of lightning filmed from the same thunderstorm. The observations
were made during the summer of 2012/2013. Five thunderstorm days
that had the largest number of detected lightning, were chosen to
be analyzed and totaled 361 negative cloud-to-ground lightning.
When the analysis was separated by thunderstorm day, significant
differences were found, the day with smaller sample size had 47
lightning registered and day with larger sample size had 117.
Besides the size of the sample, the analyzed characteristics of
the events also showed differences, the average of multiplicity
ranged between 2.8 and 5.1, the geometric mean of the interstroke
intervals ranged between 47.8 and 69.5 ms, lastly the geometric
mean of the flash duration ranged between 193.1 and 358.5 ms. The
resampling Monte Carlo method showed that the sample size did not
influence in the differences and meteorological analysis showed
that weather conditions were the same for all days. In order to
understand the variation between the characteristics of the
lightning, data from reflectivity of the cloud were used, with
height of 5 km and was estimated the contour of the area of 35
dBZ, which was considered as an estimate of the main region of
negative charge.",
committee = "Muralikrishna, Polinaya (presidente) and Pinto Junior, Osmar
(orientador) and Saraiva, Antonio Carlos Varela (orientador) and
Dal Lago, Alisson and Bourscheidt, Vandoir",
englishtitle = "Comparison of visible characteristics of negative cloud-to-ground
lightning for different days of tunderstorm in southeastern of
Brazil, observed by a network of high speed cameras.",
language = "pt",
pages = "110",
ibi = "8JMKD3MGP7W/3FL6DPS",
url = "http://urlib.net/ibi/8JMKD3MGP7W/3FL6DPS",
targetfile = "publicacao.pdf",
urlaccessdate = "04 maio 2024"
}