Amazon Basin Flood/Drought Cycle Become More Extreme, Less Predictable

[hatrack]

The Amazon River's hydrological cycle has become more extreme over the past two decades with increasing seasonal precipitation across much of the basin despite drier conditions in the southern parts of Earth's largest rainforest, finds a new study published in Geophysical Research Letters.

The research, led by Emanuel Gloor of the University of Leeds, analyzed monthly Amazon River discharge at Óbidos, a point that drains 77 percent of the Amazon Basin, and compared it with regional precipitation patterns. Suspecting that temperatures in the tropical Atlantic might be influencing rainfall — as has been suggested in other studies — the authors also assessed sea surface temperature data from the National Oceanic and Atmospheric Administration (NOAA).

The researchers found a significant intensification in the Amazon's hydrological cycle, with increased discharge during the rainy season punctuated by occasional episodes of severe drought.

"The catchment of the world's largest river is experiencing a substantial wetting trend since approximately 1990," the authors write. "This intensification of the hydrological cycle is concentrated overwhelmingly in the wet season driving progressively greater differences in Amazon peak and minimum flows."

EDIT

http://news.mongabay.com/2013/0514-amazon-discharge.html

[DCKit]

1. Who could have seen THAT coming? nt