Attribution of the river flow growth in the Plata Basin

A regression approach was used to quantitatively estimate the attribution of the notable growth in the river flows of the Plata Basin during 1960-1999. The study was conducted in seven large basins that account for most of the Plata River discharge. Annual rainfall integrated over each basin and ann...

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Detalles Bibliográficos
Autores: Doyle, M.E., Barros, V.R.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:Argentina
Institución:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
Repositorio:Biblioteca Digital (UBA-FCEN)
Idioma:inglés
OAI Identifier:paperaa:paper_08998418_v31_n15_p2234_Doyle
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_08998418_v31_n15_p2234_Doyle
Access Level:acceso abierto
Palabra clave:Land use change
Plata Basin
Precipitation
River flow
Trends
Annual rainfall
Land-use change
Natural forests
Northern basins
Paraguay
Precipitation trends
River discharge
Three phasis
Total rainfall
Uruguay
Atmospheric pressure
Deforestation
Evaporation
Nickel compounds
Phase transitions
Precipitation (chemical)
Rain
Rivers
Stream flow
Land use
El Nino-Southern Oscillation
evaporation
land use change
precipitation (climatology)
river discharge
river flow
streamflow
Land Use
Nickel Compounds
Stream Flow
Brazil
Paraguay Basin
Parana
Rio de la Plata
Glycine max
Descripción
Sumario:A regression approach was used to quantitatively estimate the attribution of the notable growth in the river flows of the Plata Basin during 1960-1999. The study was conducted in seven large basins that account for most of the Plata River discharge. Annual rainfall integrated over each basin and annual river flows at their closing points were used for the analysis. The contribution of rainfall changes during each of the three phases of El Niño-Southern Oscillation to total rainfall change in these basins was also calculated. The two main drivers for the generalized growth of the river flows were the increased precipitation and the decreased evaporation attributable to land use change, including deforestation of natural forest and crop switch from sugarcane and coffee trees to soybean. Other evaporation changes played a minor role. There was a north-south gradient in the respective importance of each driver, with land use change having greater weight in the northern basins and the precipitation increase in the southern ones. Thus, in the northern part of the Upper Paraná Basdespite the negative trend in precipitation there was a strong augment of the river flow caused by land use change. The contribution to the positive trend of the stream flows in the middle of the Plata Basin came from both land use change and increased precipitation. Finally, in the south, the Uruguay River flow change was basically due to the precipitation trend that was not only observed during the El Niño phase, but also during the Neutral phase. Only in the Middle Paraguay Basin was the shift to more frequent and intense El Niño events that took place in the 1970s an important factor in the contribution of precipitation to streamflow trends. © 2010 Royal Meteorological Society.