INVESTIGADORES
ISLA Federico Ignacio
artículos
Título:
ENSO impacts on Atlantic watersheds of South America
Autor/es:
ISLA, F.; TOLDO
Revista:
Quaternary and environmental geosciences
Editorial:
ufpr
Referencias:
Lugar: curitiba; Año: 2013 vol. 4 p. 34 - 41
ISSN:
2176-6142
Resumen:
Interannual  changes  in  precipitation  cause  significant  effects  on  the  Pacific  watersheds  of  South America. Large rivers flowing to the Atlantic Ocean as the Paraná and Uruguay are also influenced by ENSO-triggered  floods  causing  significant  impacts  on  the  economies  of  Argentina,  Brazil  and Uruguay. At the same time, the floodplains of small rivers are also sensitive to strong ENSOs. Floods occur approximately simultaneously in subtropical watersheds of Brazil and high-latitude watersheds of North Patagonia. ENSO-triggered floods were recorded during the years 1941-42, 1982-83 and 1997-98.  Several  floods  impacted  along  the  Itajaí  River  affecting  the  higher  (Blumenau  city)  and  lower estuary (Itajaí city). The Guaiba River, at the headlands of Lagoa dos Patos, has repeatedly flooded Porto Alegre. At the Río de la Plata basin, significant increases in the discharges were assigned to the Paraná  and  the  Uruguay  rivers.    The  small  basin  of  the  Quequén  Grande  River  without  extended floodplains  is  subject  to  periodic  failure  of  its  margins.  The  Colorado  River,  the  northern  limit  of Patagonia,  is  allochthonous  and  its  watershed  was  artificial  and  progressively  modified;  the  ENSO event  of  1983  caused  an  increase  in  its  salinity  due  to  the  sudden  reactivation  of  the  Desaguadero-Curacó system.