Análise do perfil vertical do vento no Centro de Lançamento de Alcântara com uso de Análise de Componentes Principais

Abstract

The objective of this study is to perform a vertical wind profile analysis using radiosonde data at the Alcântara Launch Center (ALC), using the multivariate statistical technique of the Principal Components Analysis (PCA), to verify if there is a presence of flows in the vertical wind profile. These flows may characterize local circulations and be associated with sea breeze-type circulations, and may also be associated with synoptic mesoscale level circulations, such as Low-Level Jets (LLJ). The results showed that in the first three components in the nocturnal period there is a presence of LLJ, with 85% of the variance explained. The occurrence of LLJ presented typical heights in the components, the first one with a height of 800 meters (average direction 60 to 70 degrees), the second with a height of 400 meters (mean direction 40 to 50 degrees) and the third with 200 meters average 50 to 60 degrees). These LLJs may be associated with processes related to the Planetary Boundary Layer (PBL) at night, such as maximum wind inversion and breezes.

Vertical Wind Profile Modeling at Low Levels Using a Regional Climate Model in a Case Study at the Alcântara Launch Center

“…The pressure levels in the order of 930 hPa correspond to a physical height in the order of 600 meters in the ALC. Such results show an intraseasonal variability in wind intensity at low levels and the results are consistent with the work of Silva and Corrêa (2019).…”

“…At the ALC, it was observed utilizing radiosondes at night and in the morning. Silva and Corrêa (2019) could observe flows in the vertical wind profile, these flows would characterize local circulations and were associated with sea-breeze circulations and regionally characterize circulations at the synoptic mesoscale level, such as LLJ.…”

“…Due to the geographical characteristics of ALC, the presence of sea breezes on the coast, which can characterize more intense winds close to the surface, in the study by Silva and Corrêa (2019) using radiosonde data and a multivariate statistical technique from the principal components analysis (PCA), it could characterize the existence of low-level jets (LLJ) and flows at different heights close to the surface. Corrêa et al (2019) used simulations carried out by the National Centers for Environmental Prediction (NCEP) coupled forecasting model version 2 (CFSv2)/regional climate model RegCM-4.6, the data analyzed were the information of the surface wind intensity through the analysis and comparison of the simulations carried out for the Alcântara region, on the coast of the state of Maranhão.…”