@Article{SilvaSaty:2013:EvLoEn,
author = "Silva, Ligia Alves Da and Satyamurty, Prakki",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Evolution of the Lorenz energy cycle in the intertropical
convergence zone in the South American sector of the Atlantic
Ocean",
journal = "Journal of Climate",
year = "2013",
volume = "26",
number = "10",
pages = "3466–3481",
month = "May",
keywords = "intertropical convergence zone, atmospheric circulation,
baroclinic flows, barotropic flows, large-scale motions.",
abstract = "The intertropical convergence zone (ITCZ) in the South American
sector of the Atlantic Ocean is identified using outgoing longwave
radiation (OLR) data in order to investigate the evolution of the
Lorenz energy cycle in the region dominated by this large-scale
feature. The NCEP reanalysis data are utilized to calculate the
zonal and eddy components (denoted by Z and E, respectively) of
kinetic energy K and available potential energy A (i.e., KZ, KE,
AZ, and AE) and their conversions, on a daily basis. A wavelet
decomposition of the time series is performed to detect long-term
cycles/trends in the Atlantic ITCZ region. This work also
investigates trends in sea surface temperature (SST) and sea level
pressure (SLP) in the ITCZ region and connections between the ITCZ
and the Southern Oscillation index (SOI). A strong annual cycle in
all the energy components with high peaks in austral summer is
observed. Approximately 91% of the zonal component of energy is
contained on decadal or longer time scales. The annual and
semiannual variabilities are significant and the synoptic-scale
variability is also present. The zonal component of kinetic energy
KZ presents a decreasing trend during the last 28 years, which
means a weakening of trade winds in the region studied. The values
of KZ and AE are significantly higher during the period 1982/83,
indicating that the intense El NiñoSouthern Oscillation (ENSO)
and/or the El Chich{\'o}n eruption may have affected the
circulation in the ITCZ region. The 28-yr mean energy conversion
and generation terms are in general weaker than in the hemispheric
calculations but the energy conversions proceed in the same sense
as in the hemispheric situation.",
doi = "10.1175/JCLI-D-11-00426.1",
url = "http://dx.doi.org/10.1175/JCLI-D-11-00426.1",
issn = "0894-8755",
language = "en",
targetfile = "Silva_evolution.pdf",
url = "http://dx.doi.org/10.1175/JCLI-D-11-00426.1",
urlaccessdate = "02 maio 2024"
}