chapter - Atmospheric and Oceanic Science

ABSTRACT
During approximately the last century southeastern South America has
experienced important changes in its precipitation regime, consequently affecting
the hydrologic balance of the region, and particularly of the La Plata basin.
Changes have been observed in many other regions of the world, but South
America is probably one where largest change magnitudes are found. Moreover,
the trends have intensified in the last 30 to 40 years due to changes in changes
in the atmospheric circulation and likely due to land use changes.
As a consequence of the increased precipitation in semiarid regions of
Argentina, the agricultural land extent has increased, which has been beneficial
for increased revenues, but at the same time this has created new ecological
problems. Consequently, although semiarid regions have benefited from the
increased precipitation, other regions are flooding more frequently, and in certain
cases some areas have been left permanently under water
Changes in precipitation correspond with a doubling of changes in river discharge,
so that by each 1% increase precipitation, the streamflow increases by
2% or more. This indicates that activities dependent on the streamflows are highly
vulnerable to possible regional trends related to the global Climate Change.
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CHAPTER
REGIONAL PRECIPITATION TRENDS
Ernesto Hugo Berbery 1 , Moira Doyle 2 and Vicente Barros 2
1 Universidad de Maryland.
2 CIMA/CONICET. Universidad de Buenos Aires.
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