Recent developments on the South American monsoon system

This paper reviews recent progress made in our understanding of the functioning and variability of the South American Monsoon System (SAMS) on time scales varying from synoptic to long-term variability and climate change. The SAMS contains one of the most prominent summertime climate patterns in South America, featuring a strong seasonal variability in a region lying between the Amazon and the La Plata Basin. Much of the recent progress is derived from complementary international programs, such as the Monsoon Experiment South America (MESA), as well as from ongoing international programs such as the Large Scale Biosphere Atmosphere Experiment in the Amazon Basin (LBA) and the La Plata Basin (LPB) Regional Hydroclimate Project, which includes the CLARIS LPB Europe-South America Network for Climate Change Assessment and Impact Studies in La Plata Basin Project. The latter assesses atmosphere-land surface interactions, the role of land use changes and aerosols from biomass burning considered as sources of variability and change in the SAMS functioning, characteristics and behaviour. The SAMS region is particularly susceptible to variations of climate due to the importance of hydroelectricity generation and the agricultural base of local economies. Also addressed in this report are projections of climate change and extremes, which are important for impact and vulnerability assessments. This discussion includes the need to identify and understand important processes that control the monsoonal climate, how these processes may vary and change, and how they may interact with key societal sectors, including water resource management, hydroelectric generation, agriculture, and agribusiness. This paper reports on the major contributions of MESA to the knowledge of characteristics, functioning and variability of the SAMS, and is based on recent studies and publications, and can be considered as an update of a previous review by C. S. Vera et al. (2006a). © 2010 Royal Meteorological Society.Fil:Berbery, E.H. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Vera, C.S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Saulo, A.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Progress in Pan American CLIVAR research: Understanding the South American monsoon / Progresos en las investigaciones de Pan American CLIVAR: Entendiendo el monzón sudamericano

A review of recent findings on the South American Monsoon System (SAMS) is presented. SAMS develops over a large extension of land mass crossed by the equator with surface conditions that vary from the world's largest tropical forest in Amazonia to a high desert in the Altiplano. The high Andes mountains to the west effectively block air exchanges with the Pacific Ocean, but plentiful moisture transport from the Atlantic maintains intense precipitation that is strongest over central Brazil. There is algo abundant precipitation over the subtropical plains of South America in association with moisture transport from tropical latitudes. Furthermore, midlatitude systems are important modulators of the tropical precipitation. The combination of alI these factors results in a unique seasonal evolution of convection and rainfall. The findings presented emphasize the system's complexity, and highlight the importance ofthe South American continent as the core of atmospheric linkages with the adjacent oceans. A discussion on directions for research on SAMS is algo presented. There are still outstanding questions on the relative roles played on the system evolution by the orography, local and remote heat sources, and sea surface temperature anomalies. Other remaining questions address the impact of Amazon-deforestation on water and energy cycles over the two largest river basins of South America (Amazon and La Plata). RESUMEN: Se presenta un resumen actualizado acerca del Sistema Monzónico en Sudamerica (SMS). El SMS se desarrolla sobre un continente tropical, con variadas condiciones de superficies que incluyen grandes bosques tropicales (en Amazonia), y el elevado desierto en el Altiplano. Los Andes en el oeste del continente bloquean eficientemente el intercambio de aire con el Océano Pacífico, y canalizan el transporte de humedad desde el Océano Atlántico produciendo intensa precipitación con máximo valores en el centro de Brasil y un maximo secundario sobre las llanuras subtr opicales de Sudamerica. Además, sistemas de latitudes medias son importantes moduladores de la precipitación tropical. De la combinación de todos estos factores resulta una singular evolución estacional de la convección y precipitación. Los resultados presentados enfatizan la complejidad del sistema y destacan la im portancia del continente Sudamericano como centro de las conexiones atmosféricas con los océanos adjacentes. Una discusión sobre las futuras lineas de investigación a seguir en SMS es también presentada. Existen aun importantes preguntas acerca del papel relativo que ejercen sobre la evolución del sistema la orografía, fuentes de calor locales y remotas y las anomalias de la temperatura de la superficie del mar. El impacto de la desforestación del Amazonas en al balance hídrico y de energía de las dos más grandes cuencas en Sudamerica (de los rios Amazonas y de la Plata) tambien necesita ser estudiado con mayor profundidad.Pages: 1-3

Recent developments on the South American monsoon system

This paper reviews recent progress made in our understanding of the functioning and variability of the South American Monsoon System (SAMS) on time scales varying from synoptic to long-term variability and climate change. The SAMS contains one of the most prominent summertime climate patterns in South America, featuring a strong seasonal variability in a region lying between the Amazon and the La Plata Basin. Much of the recent progress is derived from complementary international programs, such as the Monsoon Experiment South America (MESA), as well as from ongoing international programs such as the Large Scale Biosphere Atmosphere Experiment in the Amazon Basin (LBA) and the La Plata Basin (LPB) Regional Hydroclimate Project, which includes the CLARIS LPB Europe-South America Network for Climate Change Assessment and Impact Studies in La Plata Basin Project. The latter assesses atmosphere-land surface interactions, the role of land use changes and aerosols from biomass burning considered as sources of variability and change in the SAMS functioning, characteristics and behaviour. The SAMS region is particularly susceptible to variations of climate due to the importance of hydroelectricity generation and the agricultural base of local economies. Also addressed in this report are projections of climate change and extremes, which are important for impact and vulnerability assessments. This discussion includes the need to identify and understand important processes that control the monsoonal climate, how these processes may vary and change, and how they may interact with key societal sectors, including water resource management, hydroelectric generation, agriculture, and agribusiness. This paper reports on the major contributions of MESA to the knowledge of characteristics, functioning and variability of the SAMS, and is based on recent studies and publications, and can be considered as an update of a previous review by C. S. Vera et al. (2006a).Fil: Marengo, J. A.. Centro de Previsao de Tempo e Estudos Climáticos. Instituto Nacional de Pesquisas Espaciais; BrasilFil: Liebmann, B.. Cooperative Institute for Research In Environmental Sciences; Estados UnidosFil: Grimm, A. M.. Universidade Federal do Paraná; BrasilFil: Misra, V.. Florida State University; Estados UnidosFil: Silva Dias, P. L.. Universidade de Sao Paulo; BrasilFil: Cavalcanti, I. F. A.. Centro de Previsao de Tempo e Estudos Climáticos. Instituto Nacional de Pesquisas Espaciais; BrasilFil: Carvalho, L. M. V.. University of California; Estados UnidosFil: Berbery, E. H.. University of Maryland; Estados UnidosFil: Ambrizzi, T.. Universidade de Sao Paulo; BrasilFil: Vera, Carolina Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmosfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmosfera; ArgentinaFil: Saulo, Andrea Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmosfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmosfera; ArgentinaFil: Nogues Paegle, J.. University of Utah; Estados UnidosFil: Zipser, E.. University of Utah; Estados UnidosFil: Seth, A.. University Of Connecticut; Estados UnidosFil: Alves, L. M.. Universidade de Sao Paulo; Brasi