Easterly Wave Disturbances over Northeast Brazil: An Observational Analysis
Joint Authors
Gomes, Helber Barros
Herdies, Dirceu Luís
Hodges, Kevin
Pontes da Silva, Bruce Francisco
Ambrizzi, Tercio
Source
Issue
Vol. 2015, Issue 2015 (31 Dec. 2015), pp.1-20, 20 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2015-06-09
Country of Publication
Egypt
No. of Pages
20
Main Subjects
Abstract EN
This paper aims to identify the circulation associated with Easterly Wave Disturbances (EWDs) that propagate toward the Eastern Northeast Brazil (ENEB) and their impact on the rainfall over ENEB during 2006 and 2007 rainy seasons (April–July).
The EWDs identification and trajectory are analyzed using an automatic tracking technique (TracKH).
The EWDs circulation patterns and their main features were obtained using the composite technique.
To evaluate the TracKH efficiency, a validation was done by comparing the EWDs number tracked against observed cases obtained from an observational analysis.
The mean characteristics of EWDs are 5.5-day period, propagation speed of ~9.5 m·s−1, and a 4500 km wavelength.
A synoptic analysis shows that between days −2 d and 0 d, the low level winds presented cyclonic relative vorticity and convergence anomalies both in 2006 and 2007.
The EWDs signals are strongest at low levels.
The EWDs propagation is associated with relative humidity and precipitation positive anomalies and OLR and omega negative anomalies.
The EWDs tracks are seen over all ENEB and their lysis occurs between the ENEB and marginally inside the continent.
The tracking captured 71% of EWDs in all periods, indicating that an objective analysis is a promising method for EWDs detection.
American Psychological Association (APA)
Gomes, Helber Barros& Ambrizzi, Tercio& Herdies, Dirceu Luís& Hodges, Kevin& Pontes da Silva, Bruce Francisco. 2015. Easterly Wave Disturbances over Northeast Brazil: An Observational Analysis. Advances in Meteorology،Vol. 2015, no. 2015, pp.1-20.
https://search.emarefa.net/detail/BIM-1052671
Modern Language Association (MLA)
Gomes, Helber Barros…[et al.]. Easterly Wave Disturbances over Northeast Brazil: An Observational Analysis. Advances in Meteorology No. 2015 (2015), pp.1-20.
https://search.emarefa.net/detail/BIM-1052671
American Medical Association (AMA)
Gomes, Helber Barros& Ambrizzi, Tercio& Herdies, Dirceu Luís& Hodges, Kevin& Pontes da Silva, Bruce Francisco. Easterly Wave Disturbances over Northeast Brazil: An Observational Analysis. Advances in Meteorology. 2015. Vol. 2015, no. 2015, pp.1-20.
https://search.emarefa.net/detail/BIM-1052671
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-1052671