@InProceedings{VazEsco:2014:CrDeFr,
author = "Vaz, Jo{\~a}o Caetano Mancini and Escobar, Gustavo Carlos Juan",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Crit{\'e}rio de Detec{\c{c}}{\~a}o de Friagens Para o
Munic{\'{\i}}pio de Cuiab{\'a} (MT) a Partir de
Decl{\'{\i}}nios Di{\'a}rios de Temperatura",
year = "2014",
organization = "Congresso Brasileiro de Meteorologia, 18. (CBMET).",
keywords = "Friagem, Decl{\'{\i}}nios di{\'a}rios de temperatura.",
abstract = "As ondas de frio que frequentam grande parte das Regi{\~o}es Sul
e Sudeste do Brasil, podem atingir de quatro a cinco vezes ao ano
a Regi{\~a}o Centro-Oeste e o sul da Regi{\~a}o Norte do
pa{\'{\i}}s, e ocasionalmente provocar decl{\'{\i}}nios
significativos de temperatura (PARMENTER, 1976). Este
fen{\^o}meno {\'e} conhecido como friagem e pode gerar
significantes danos econ{\^o}micos, tanto na
popula{\c{c}}{\~a}o quanto na agricultura. O objetivo deste
trabalho {\'e} desenvolver um crit{\'e}rio de
detec{\c{c}}{\~a}o de friagens para o Munic{\'{\i}}pio de
Cuiab{\'a} (MT) baseado no decl{\'{\i}}nio di{\'a}rio da
temperatura e na temperatura final ocorrida ap{\'o}s a entrada do
ar frio. Para tanto, utilizaram-se an{\'a}lises de cartas
sin{\'o}ticas de superf{\'{\i}}cie, elaboradas pelo Grupo de
Previs{\~a}o de Tempo (CPTEC/INPE), entre os meses de abril e
novembro no per{\'{\i}}odo 2007-2012 e dados observacionais
di{\'a}rios de temperaturas m{\'{\i}}nimas e m{\'a}ximas
provenientes do Instituto Nacional de Meteorologia (INMET) para o
per{\'{\i}}odo 1961-2012. Atrav{\'e}s das cartas de
superf{\'{\i}}cie identificou-se 23 casos de frentes frias que
atingiram Cuiab{\'a} entre 2007 e 2012. Com intuito de
compreender melhor a rela{\c{c}}{\~a}o entre os
decl{\'{\i}}nios di{\'a}rios de temperatura e a temperatura
final nos casos identificados, foram plotados os
decl{\'{\i}}nios di{\'a}rios das temperaturas m{\'{\i}}nimas
e m{\'a}ximas versus os respectivos valores finais de temperatura
observada ap{\'o}s a passagem da frente fria. As an{\'a}lises
revelaram que as temperaturas m{\'a}ximas mais baixas ocorridas
ap{\'o}s a passagem do sistema frontal foram registradas com
maior frequ{\^e}ncia quando o decl{\'{\i}}nio di{\'a}rio de
temperatura m{\'a}xima associado era igual ou superior a 10°C.
Notou-se que quando o avan{\c{c}}o da frente fria ocorria
rapidamente, o decl{\'{\i}}nio significativo de temperatura
m{\'a}xima se dava no mesmo dia da chegada do sistema frontal.
J{\'a} quando a frente fria avan{\c{c}}ava mais lentamente, o
impacto do decl{\'{\i}}nio ocorria rec{\'e}m no dia seguinte.
Em rela{\c{c}}{\~a}o {\`a} temperatura m{\'{\i}}nima,
verificou-se que os decl{\'{\i}}nios di{\'a}rios associados
n{\~a}o apresentaram um comportamento padronizado similar {\`a}
temperatura m{\'a}xima. Desta maneira, utilizou-se a temperatura
m{\'a}xima como vari{\'a}vel de estudo na elabora{\c{c}}{\~a}o
do crit{\'e}rio de detec{\c{c}}{\~a}o de friagem. Al{\'e}m
disso, tamb{\'e}m verificou-se que, para os decl{\'{\i}}nios
di{\'a}rios de temperatura m{\'a}xima iguais ou superiores a
10°C, a temperatura m{\'a}xima ap{\'o}s a passagem da frente
fria era na maioria dos casos inferior a ¯TM{\'a}x-2\σ,
correspondente a uma s{\'e}rie hist{\'o}rica de 40 anos. A
partir destes resultados, o crit{\'e}rio de friagem foi
determinado por decl{\'{\i}}nios di{\'a}rios de temperatura
m{\'a}xima iguais ou superiores a 10°C e temperauras m{\'a}ximas
finais (ap{\'o}s a passagem da frente fria) inferiores a
¯TM{\'a}x-2\σ. A aplica{\c{c}}{\~a}o deste crit{\'e}rio
{\`a} s{\'e}rie hist{\'o}rica de temperatura m{\'a}xima de
1961-2012 identificou 217 casos de friagens, sendo que julho e
novembro foram os meses com o maior (47) e menor (6) n{\'u}mero
de casos, respectivamente. Por fim foram analisados dois casos de
friagens associados com situa{\c{c}}{\~o}es meteorol{\'o}gicas
diferentes relacionadas com a velocidade de avan{\c{c}}o do
sistema frontal frios./ The cold waves attending much of South and
Southeast Brazil, can reach four to five times a year the Midwest
Region and the southern North of the country, and occasionally
cause significant declines in temperature (PARMENTER 1976 ). This
phenomenon is known as {"}friagem{"} and can generate significant
economic damage, both in population and in agriculture. The
objective of this work is to develop a criterion for detecting
friagens for Cuiab{\'a} city (MT) based on daily temperature
decline and in the final temperature occurred after the entry of
cold air. For this, synoptic maps surface analysis, prepared by
the Weather Forecast Group from Weather Forecast and Climate Study
Center (CPTEC / INPE) were used, between April and November during
the period 2007-2012 and daily observational minimum and maximum
temperatures data from the National Institute of Meteorology
(INMET) for the period 1961-2012. Through the surface maps were
identified 23 cases of cold fronts that reached Cuiab{\'a}
between 2007 and 2012. In order to better understand the
relationship between the daily temperature declines and the final
temperature in the cases identified, the minimum and maximum daily
temperature declines were plotted versus their final temperature
observed after the passage of the cold front. The analysis
revealed that the maximum lower temperatures occurred after the
passage of the frontal system, were recorded more frequently when
the maximum daily temperature associated decline was less than 10
° C. It was noted that when the advance of the cold front occurred
quickly, significant decline in maximum temperature was given on
the day of arrival of the frontal system. But when the cold front
progressed more slowly, the impact of the decline occurred
immediately on the following day. Regarding the minimum
temperature, it was found that the daily associated declines did
not show a similar behavior defaults to maximum temperature. Thus,
the maximum temperature was used as a study variable in the
development of detection criterion of coldness. Furthermore, it
was also found that, for the maximum daily declines greater than
or equal to 10 ° C, the maximum temperature after the passage of
the cold front was less than-Tmax-2\σ for most of the cases,
corresponding to 40 years time series. From these results, the
friagem criterion was determined by daily maximum temperature
declines of greater than or equal to 10 ° C and maximum
temperatures final temperature (after the passage of the cold
front) below Tmax-2\σ. Applying this test to the time series
of maximum temperature of 1961-2012 were identified 217 cases of
friagens, and July and November were the months with the highest
(47) and lowest (6) number of cases, respectively. To finalize two
cases of friagens associated with different weather situations
related to the rate of advance of the cold frontal system were
analyzed.",
conference-location = "Recife, PE",
conference-year = "3-6 nov., 2014",
targetfile = "Vaz_Criterio.pdf",
urlaccessdate = "25 abr. 2024"
}