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How Do La Niña Events Disturb The Summer Monsoon System In Brazil?

A. Grimm
Published 2004 · Geology

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Abstract The rainy season in most of Brazil is associated with the summer monsoon regime in South America. The quality of this season is important because it rains little during the rest of the year over most of the country. In this study, the influence of La Niña events on the summer monsoon circulation, rainfall and temperature is analyzed with seasonal and monthly resolution, using data from a dense network of stations, giving a comprehensive view of the impact of these events. The expected precipitation percentiles during the monsoon season of La Niña events are calculated, as well as anomalies of surface temperature and thermodynamic parameters. This information is analyzed jointly with anomaly composites of several circulation parameters. The analysis shows that some anomalies, which are consistent and important during part of the season, are smoothed out in a seasonal analysis. There are abrupt changes of anomalies within the summer monsoon season, suggesting the prevalence of regional processes over remote influences during part of the season. In spring there are positive precipitation anomalies in north and central-east Brazil and negative ones in south Brazil. These precipitation anomalies are favored by the perturbation in the Walker and Hadley circulation over the eastern Pacific and South America, and by perturbations in the rotational circulation over southern South America. Northerly moisture inflow from the Atlantic into northern South America is emphasized and diverted towards the mouth of the Amazon by the low-level cyclonic anomaly north of the equator. In December and January, probably triggered by anomalous surface cooling during the spring, there is an anomalous low-level divergence and an anticyclonic anomaly over southeast Brazil. This anomalous circulation directs moisture flux towards south Brazil, causing moisture convergence in part of this region and part of central-west Brazil. The thermodynamic structure in central-east Brazil does not favor precipitation over this region, and the wet anomalies in north Brazil are displaced northward. The dry anomalies in south Brazil almost disappear and even turn positive. In February, after the strongly below normal precipitation of January, the surface temperature anomalies turn positive over southeast Brazil. The low-level anticyclonic anomaly is much weaker than in January. There are positive rainfall anomalies in north Brazil and in the South Atlantic Convergence Zone, and negative ones return to south Brazil.
This paper references
10.1175/1520-0442(1989)002<0268:PPAWTH>2.0.CO;2
Precipitation Patterns Associated with the High Index Phase of the Southern Oscillation
C. Ropelewski (1989)
10.1175/1520-0442(1988)001<0172:PVOTCA>2.0.CO;2
Precipitation Variability over the Caribbean and Tropical Americas Associated with the Southern Oscillation
J. Rogers (1988)
10.1175/1520-0442(1998)011<2863:PAISBA>2.0.CO;2
Precipitation Anomalies in Southern Brazil Associated with El Niño and La Niña Events
A. Grimm (1998)
10.1175/1520-0442(1996)009<1531:LSAMTA>2.0.CO;2
Large-Scale Atmospheric Moisture Transport as Evaluated in the NCEP/NCAR and the NASA/DAO Reanalyses
K. C. Mo (1996)
10.1175/1520-0442(2003)016<0263:TENIOT>2.0.CO;2
The El Nino Impact on the Summer Monsoon in Brazil: Regional Processes versus Remote Influences
A. Grimm (2003)
10.1175/1520-0493(1980)108<1046:TCOEPT>2.0.CO;2
The Computation of Equivalent Potential Temperature
D. Bolton (1980)
10.1007/BF00868215
Characteristics of rainfall over Brazil: Annual variations and connections with the Southern Oscillation
V. B. Rao (1990)
10.1002/JOC.700
Principal modes of interannual and decadal variability of summer rainfall over South America
J. Zhou (2001)
10.2151/JMSJ.80.33
Defining Three Rainy Seasons and the Hydrological Summer Monsoon in Korea using Available Water Resources Index
H. Byun (2002)
10.1175/1520-0442(2000)013<0035:CVISSA>2.0.CO;2
Climate Variability in Southern South America Associated with El Niño and La Niña Events.
A. Grimm (2000)
10.1175/1520-0493(1988)116<0505:OTFOTS>2.0.CO;2
On the Functioning of the Southern Oscillation in the South American Sector. Part I: Surface Climate
P. Aceituno (1988)
10.1175/1520-0477(1997)078<2771:TDOENO>2.0.CO;2
The Definition of El Niño.
K. E. Trenberth (1997)
10.1002/joc.3370120808
Interannual variability of surface climate in the Amazon basin
J. Marengo (1992)
10.2151/JMSJ.80.21
Relationship between Temperature and Circulation in Southeastern South America and its Influence from El Nino and La Nina Events
V. Barros (2002)
10.1175/1520-0442(1994)007<1286:ENSOIO>2.0.CO;2
El Niño-Southern Oscillation impact on rainfall in Uruguay
Gabriel Pisciottano (1994)



This paper is referenced by
10.3354/CR01381
ENSO influence on La Plata Basin precipitation in the HadGEM2-ES model
Renata G. Tedeschi (2016)
10.1016/J.JHYDROL.2015.01.028
Precipitation extremes over La Plata Basin – Review and new results from observations and climate simulations
I. Cavalcanti (2015)
10.1590/0102-7786331015
Variabilidade Interanual da Precipitação e Fluxo de Umidade Sobre a Amazônia Usando o QTCM
Aline Corrêa de Sousa (2018)
10.1002/JGRD.50282
A study of the long-term variability of thunderstorm days in southeast Brazil
O. Pinto (2013)
10.26848/rbgf.v11.3.p728-744
Comportamento climático do balanço do vento térmico na América do Sul de acordo com os eventos ENOS: Estudo preliminar (Climatic behavior of thermal wind balance in South America according to ENSO events: Preliminary study)
Mônica Vaz Lima (2018)
10.1016/J.PALAEO.2018.09.023
Enhanced mercury deposition by Amazonian orographic precipitation: Evidence from high-elevation Holocene records of the Lake Titicaca region (Bolivia)
Stéphane Guédron (2018)
10.1029/2006GL026821
Climate change and interannual variability of precipitation in South America
A. Grimm (2006)
10.1029/2018JC014812
Propagating Modes of Variability and Their Impact on the Western Boundary Current in the South Atlantic
Sudip Majumder (2019)
Three Decades of Anthropogenic Fire Activity in a Neotropical Agricultural Frontier
G. A. Daldegan (2019)
10.1007/s00382-020-05442-9
Revisiting remote drivers of the 2014 drought in South-Eastern Brazil
K. Finke (2020)
10.1007/978-90-481-2672-9_7
Teleconnections into South America from the Tropics and Extratropics on Interannual and Intraseasonal Timescales
Alice Marlene Grimm (2009)
10.1175/2008JCLI2345.1
Interannual Variability and Seasonal Evolution of Summer Monsoon Rainfall in South America
Alice Marlene Grimm (2009)
10.1002/JOC.2254
Recent developments on the South American monsoon system
J. Marengo (2012)
10.1002/9781444306408.CH14
Modern Andean Rainfall Variation during ENSO Cycles and its Impact on the Amazon Drainage Basin
Bodo Bookhagen (2010)
10.22456/1807-9806.78197
Relações entre as razões de isótopo de oxigênio na neve e no gelo do Nevado Illimani (Bolívia) com a variabilidade temporal da precipitação sobre a América do Sul
Éder Leandro Bayer Maier (2016)
10.5935/1984-2295.20160055
Analysis of relations between δ18O the ice core of Nevado Illimani (Bolivia) with the precipitations in the tropical region of South America (1929-1998)
Tainã Costa Peres (2016)
10.1002/JOC.5999
ENSO teleconnections to the Indian summer monsoon under changing climate
Indrani Roy (2019)
As influências da variabilidade climática no desempenho agronômico do milho na mesorregião Oeste Catarinense
Diego Souza Venâncio (2014)
10.1002/JOC.5891
Effects of two different La Niña types on the South American rainfall
R. V. Andreoli (2019)
10.2166/NH.2014.074
Drought analysis in southern Paraguay, Brazil and northern Argentina: regionalization, occurrence rate and rainfall thresholds
M. Portela (2015)
10.1007/S00382-010-0881-4
Daily atmospheric variability in the South American monsoon system
Venkat Krishnamurthy (2011)
10.1590/0102-778620130579
ANÁLISES CLIMÁTICAS: O FILTRO HODRICK-PRESCOTT APLICADO AOS ÍNDICES ATMOSFÉRICOS DA OSCILAÇÃO SUL E DA OSCILAÇÃO DO ATLÂNTICO NORTE
Anderlan Henrique Batista Siqueira (2015)
10.1016/J.GLOPLACHA.2014.11.003
Assessing the impact of El Niño Modoki on seasonal precipitation in Colombia
Samir Córdoba-Machado (2015)
10.1007/s10584-014-1260-7
Analysis of meteorological drought episodes in Paraguay
J. Benitez (2014)
10.1016/J.JHYDROL.2015.01.009
A climate informed model for nonstationary flood risk prediction: Application to Negro River at Manaus, Amazonia
Carlos H.R. Lima (2015)
9. THE SOUTH AMERICAN MONSOON SYSTEM
Brant Liebmann (2010)
10.1007/s00704-014-1351-4
Sensitivity of tree ring growth to local and large-scale climate variability in a region of Southeastern Brazil
Alejandro Venegas-González (2015)
10.1002/JOC.5044
Lifecycle of South American Monsoon System simulated by CPTEC/INPE AGCM
Iracema F. A. Cavalcanti (2017)
Productivity of maize, and occurrence of enso precipitation in the region of the middle Paranapanema, SP, Brazil.
A. Prela-Pântano (2011)
10.1175/2009JHM1108.1
The Amplification of the ENSO Forcing over Equatorial Amazon
Vasubandhu Misra (2009)
10.1002/esp.4745
Hidden in plain sight: how finding a lake in the Brazilian Pantanal improves understanding of wetland hydrogeomorphology
Eder Merino (2020)
10.1007/S00477-010-0420-1
Interannual climate variability in South America: impacts on seasonal precipitation, extreme events, and possible effects of climate change
A. Grimm (2011)
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