Abner Pinheiro de Matos, Júlia Clarinda Paiva Cohen


The precipitation in Belem region is mainly due the large atmospheric systems such as ITCZ and mesoscale systems like the Instability Lines. Beside these systems, there are convective systems forced locally which also promote precipitation in this region. This paper studies a convective system, observed for first time during the campaign of the RAIN project, which is called Micro Instability Line Fluvial (MLF) because its formation is associated with river breeze circulation. The GOES 12 satellite data, radar band X, anemometer, rain gauges, disdrometer, and NCEP reanalyzes were used to study this MLF. High-resolution numerical simulation with the BRAMS model was made for this MLF, using two grids with horizontal resolution of 3 km and 1 km. The simulation results showed that the MLF was formed by river breeze from the Marajo Bay, causing precipitation since the early stages in Belem area until this MLF was on the west bank of the Marajo bay. During its propagation westward, this MLF had increased its intensity, which was maximum over the Bay of Marajo, where there is intense transportation of cargo and passengers, and shipwrecks are the most frequent type of accidents.


Micro line. Reflectivity. River breeze. BRAMS.


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DOI: http://dx.doi.org/10.5902/2179460X19814


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Ciência e Natura

EISSN  2179-460X

ISSN 0100-8307

DOI 10.5902


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