@Article{OliveiraOyam:2020:ObFe,
author = "Oliveira, Fernando Pereira de and Oyama, M. D.",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
de Aeron{\'a}utica e Espa{\c{c}}o (IAE)}",
title = "Squall-line initiation over the northern coast of Brazil in March:
observational features",
journal = "Meteorological Applications",
year = "2020",
volume = "27",
number = "1",
pages = "e1799",
month = "Jan.",
keywords = "coastal convection, deep convection, mesoscale, squall line.",
abstract = "The daily cycle of atmospheric conditions related to squall-line
(SL) initiation over the northern coast of Brazil (NCB) was
obtained for a specific month (March) over the course of a decade
(2004-2013). March falls during the NCB's rainy season. A
comparison of atmospheric conditions between two categories, the
most intense SL events (SLC+) and the weakest coastal convection
events (CC-), was carried out. For both categories, the daily
cycle of convective cluster properties (i.e. number and area) over
the NCB showed that the transition from shallow to deep convection
occurred from 1200 to 1500 UTC, and the development of multicell
storms occurred from 1500 to 1800 UTC. From 1800 to 2100 UTC for
the SLC+ events, the number of clusters decreased sharply, and the
area slightly expanded, which indicated upscaling via merging; for
the CC- events, merging was a secondary mechanism, and the
clusters did not experience upscaling. Atmospheric conditions were
computed from the ERA-Interim reanalysis data. By focusing on the
significant differences between the categories, it was found that
SL initiation was related to a higher moisture content at
approximately 700hPa for all analysis times (0600, 1200, 1800 and
0000 UTC) and to a stronger low-level moisture convergence from
0600 to 1800 UTC, mid-level upward motion from 1200 to 0000 UTC,
low-level convergence at 1200 UTC, and upper-level divergence from
1800 to 0000 UTC.",
doi = "10.1002/met.1799",
url = "http://dx.doi.org/10.1002/met.1799",
issn = "1350-4827",
language = "en",
targetfile = "oliveira_squall.pdf",
urlaccessdate = "27 abr. 2024"
}