Open AccessPicos na velocidade do vento e sua relação com aumentos em fluxos de escalares na atmosfera tropical noturna: Estudo de caso
Author(s) -
Francisco Otávio Miranda,
Leonardo Deane de Abreu Sá,
Celso von Randow,
Fernando M. Ramos,
A. O. Manzi
Publication year - 2020
Publication title -
ciência e natura
Language(s) - English
Resource type - Journals
eISSN - 2179-460X
pISSN - 0100-8307
DOI - 10.5902/2179460x45354
Subject(s) - physics , amplitude , turbulence , wind speed , scalar (mathematics) , atmospheric sciences , atmosphere (unit) , meteorology , mathematics , optics , geometry
Some physical aspects related to the occurrence of nocturnal instability-inducing intense peaks in wind speed (here abbreviated by PV.) in the tropical atmosphere above forest were investigated. Such phenomena cause strong variations in turbulent signals, occurrence of strong turbulence regimes, and significant increases in scalar fluxes. Was found that these events that occur during strong turbulence regimes can be preceded and succeeded by low frequency oscillations in environmental variables and that the significant increase in scalar fluxes observed is associated with the existence of a relative maximum wind speed value (). Procedures are applied to the data used here to enable the construction of phase space diagrams in order to better analyze the increase in amplitude of low frequency oscillations observed before PV outbreak, as well as the decrease in amplitude after PV. The aforementioned phase diagrams are used to obtain repulsor and attractor limit cycles, which respectively precede and succeed the peaks in wind speed. Weather radar images are also used to further investigate the studied atmospheric phenomenon.