@InProceedings{LyraHGSSGQMCCVFP:2024:ExPrEv,
author = "Lyra, Matheus Jos{\'e} Arruda and Herdies, Dirceu Luis and Gomes,
Helber and Silva, Maria Cristina Lemos and Silva, Fabricio Daniel
dos Santos and Gomes, Heliof{\'a}bio Barros and Quadro,
M{\'a}rio Francisco Leal de and Mantovani J{\'u}nior, Jos{\'e}
Ant{\^o}nio and Coelho, William Ferreira and Calvetti, Leonardo
and Vendrasco, {\'E}der Paulo and Figueroa, Silvio Nilo and
Pendharkar, Jayant",
affiliation = "{Universidade Federal de Alagoas (UFAL)} and {Instituto Nacional
de Pesquisas Espaciais (INPE)} and {Universidade Federal de
Alagoas (UFAL)} and {Universidade Federal de Alagoas (UFAL)} and
{Universidade Federal de Alagoas (UFAL)} and {Universidade Federal
de Alagoas (UFAL)} and {} and {Instituto Nacional de Pesquisas
Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais
(INPE)} and {Universidade Federal de Pelotas (UFPel)} and
{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)}",
title = "Extreme Precipitation Events in Northeast Brazil Triggered by
Different Synoptic Scale Systems",
booktitle = "Proceedings...",
year = "2024",
organization = "American Meteorologial Society Annual Meeting, 104.",
publisher = "AMS",
abstract = "This study aims to analyze the synoptic patterns responsible for
the different systems development that led to extreme
precipitation events in Brazilian Northeast (BNE) on three
different dates - May 27, 2017, February 20, 2020, and March 14,
2023. Despite having the driest region of Brazil (The Sert{\~a}o)
with rainfall values not exceeding 400 mm per year, BNE is
characterized by the influence of several synoptic-scale systems
throughout the year that contribute to extreme precipitation
events over the region. ERA5 global reanalysis data have been used
for synoptic and vertical structure evaluation as a first step of
analysis. MERGE precipitation product and pluviometric stations
were used to document accumulated precipitation produced by these
events. The following step will consist of conducting simulations
at a very high-resolution using the Model for Prediction Across
Scales (MPAS) to assess its ability to represent the circulation
patterns associated with the extreme precipitation events
analyzed. The three cases were situated in different sectors of
BNE and were caused by different synoptic-scale systems: Easterly
Wave Disturbances (EWD), Upper Tropospheric Cyclonic Vortex (UTCV)
and Intertropical Convergence Zone (ITCZ), respectively. The first
analyzed event was caused by an EWD, where the axis of a trough at
the 850 hPa level was observed along with intense moisture
transport along the eastern coast of BNE, resulting in an intense
rainfall of 173 mm/24h. The second event, considered more
atypical, was triggered by an UTCV, also along the BNE eastern
coast. The precipitation from this system resulted in 68 mm in
just 4 hours, surpassing the historical February average in
Macei{\'o}, Alagoas. Finally, the third event was caused by the
ITCZ and a Mesoscale Convective System (MCS) convection, resulting
in heavy rains (140 mm/24h) over the Maranh{\~a}o state,
especially in the city of S{\~a}o Lu{\'{\i}}s. Despite the
different circulation patterns of the analyzed synoptic systems,
some similar characteristics were identified, such as intense
moisture convergence and strong wind shear, in addition to
negative surface relative vorticity. Topography played a
significant role. The first case analyzed (on the east coast)
recorded the highest rainfall among the three cases, despite not
presenting cloudiness with great vertical development. This
occurred due to the high convergence of moisture transport
combined with the elevated relief to the west, which facilitated
increased convective activity. Vertical profiles of specific
humidity and vertical air movements proved to be very important
fields for analyzing the circulation patterns of synoptic scale
systems, which in turn have quite different characteristics.
Furthermore, it demonstrated its significance as a valuable
instrument for enhancing comprehension of the vertical
thermodynamic structures of the extreme precipitation events.",
conference-location = "Baltimore, MD",
conference-year = "28 jan. - 01 feb. 2024",
language = "en",
urlaccessdate = "15 jun. 2024"
}