@InProceedings{GanLima:2016:InVaSo,
author = "Gan, Manoel Alonso and Lima, Jeane Rafaele Ara{\'u}jo",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Interannual variability of South American monsoon circulation",
booktitle = "Abstracts...",
year = "2016",
organization = "European Geophysical Society General Assembly",
note = "Geophysical Research Abstract, v.18",
abstract = "The South America Monsoon System (SAMS) is responsible for
influencing the atmospheric circulation and precipitation over
most of tropical South America (SA) during the summer season.
Studies for aiming to understand the temporal variability of this
system have great value to the scientific community, because the
processes that control the monsoon climate are not totally clear.
Thus, the main objective of this research is to investigate the
possible large-scale climatic factors and the remote interaction
mechanisms, which may be associated with summer season interannual
variability focusing on identifying the main differences between
dry and wet extremes rainy season in the South-eastern Amazon
Basin (SAB), Central-West (WC) and Southeast (SE) of Brazil, which
are areas influenced by the summer monsoon regime. For such
analyzes, Pearson correlations, quantile method and composite
analysis were used during the period from 1979 to 2014. The
correlation between precipitation anomaly in SAB and the sea
surface temperature anomaly (SSTA) and wind at 850hPa and 300hPa
indicate El Niņo-Southern Oscillation (ENSO) influence.
Precipitation anomalies in WC did not show significant correlation
with SSTA. However, a pattern similar to ENSO Modoki type was
observed in the composite analysis. At 850 hPa, the presence of an
anomalous cyclonic (anticyclonic) circulation was observed over
the central region of SA during wet (dry) summers seasons. Over SE
region of Brazil, a dipole SSTA pattern over the South Atlantic
was identi- fied, as well the presence of anomalous circulations
with an equivalent barotropic structure over these SSTA areas.
This pattern is more evident in case of dry summer on the SE. At
300 hPa, the wave train between 30\◦S-60\◦S was
observed presenting a feature curvature from 120\◦W
reaching SA, similar to the Pacific-South American pattern (PSA).
Analysis of the summer interannual variability indicated the
manifestation of wet summers more frequently than dry summers in
the SAB during the last decade. On the other hand the SE region
experienced rainfall deficit during the last five summer seasons,
with the summer of 2013/2014 considered the driest over the last
35 summers studied in this region.",
conference-location = "Vienna, Austria",
conference-year = "17-22 Apr.",
language = "en",
targetfile = "gan_interannual.pdf",
urlaccessdate = "27 abr. 2024"
}