@Article{MarengoAlSoRoCaPaDi:2013:FlAmDr,
author = "Marengo, Jos{\'e} Antonio and Alves, Lincoln Muniz and Soares,
Wagner Rodrigues and Rodriguez, Daniel Andres and Camargo, Helio
and Paredes Riveros, Marco and Diaz Pablo, Amelia",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de
Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)} and {Centro de Monitoramento e Alerta a
Desastres} and {Servi{\c{c}}o Nacional de Meteorologia e
Hidrologia del Peru} and {Servi{\c{c}}o Nacional de Meteorologia
e Hidrologia del Peru}",
title = "Two Contrasting Severe Seasonal Extremes in Tropical South America
in 2012: Flood in Amazonia and Drought in Northeast Brazil",
journal = "Journal of Climate",
year = "2013",
volume = "26",
number = "22",
pages = "9137--9154",
month = "Nov.",
keywords = "Climate change, Climate classification, regimes, Climate
prediction, Climate variability.",
abstract = "Two simultaneous extreme events affected tropical South America to
the east of the Andes during the austral summer and fall of 2012:
a severe drought in Northeast Brazil and intense rainfall and
floods in Amazonia, both considered records for the last 50 years.
Changes in atmospheric circulation and rainfall were consistent
with the notion of an active role of colder-than-normal surface
waters in the equatorial Pacific, with above-normal upward motion
and rainfall in western Amazonia and increased subsidence over
Northeast Brazil. Atmospheric circulation and soil moisture
anomalies in the region contributed to an intensified transport of
Atlantic moisture into the western part of Amazonia then turning
southward to the southern Amazonia region, where the Chaco low was
intensified. This was favored by the intensification of
subtropical high pressure over the region, associated with an
anomalously intense and northward-displaced Atlantic high over a
relatively colder subtropical South Atlantic Ocean. This pattern
observed in 2012 was not found during other wet years in Amazonia
such as 1989, 1999, and 2009. This suggests La Nina as the main
cause of the abundant rainfall in western Amazonia from October to
December, with wet conditions starting earlier and remaining until
March 2012, mostly in northwestern Amazonia. The anomalously high
river levels during the following May-July were a consequence of
this early and abundant rainy season during the previous summer.
In Northeast Brazil, dry conditions started to appear in December
2011 in the northern sector and then extended to the entire region
by the peak of the rainy season of February-May 2012.",
doi = "10.1175/JCLI-D-12-00642.1",
url = "http://dx.doi.org/10.1175/JCLI-D-12-00642.1",
issn = "0894-8755",
label = "isi 2013-11",
language = "en",
urlaccessdate = "15 jun. 2024"
}