2. New model better represents global climate effects in Amazon basin
El NioSouthern Oscillation (ENSO) cycles strongly influence the interannual variability of climate, weather patterns, and streamflow in South America's Amazon basin. However, current global climate models (GCMs) are unable to exactly capture this variability, in part because the grids used in GCMs (roughly 2 degrees degrees of latitude and longitude) are too large to properly resolve topographical features such as the Andes, which have a narrow width (only 200? kilometers (120-190 miles). Seeking to correct for this, Medvigy et al. use the Ocean-Land-Atmosphere Model (OLAM), a new Earth System Model (ESM), which is capable of simulating regions such as mountain ranges at selectively high resolution while the remainder of the world continues to be simulated at coarser resolution. They find that when the Andes are resolved more coarsely than 100 km (60 mi), the model incorrectly simulates ENSO effects such as the dry anomalies that are observed in the Amazon during ENSO events. In contrast, the model correctly simulates the observed dry conditions provided that the Andes are simulated at resolutions finer than 100 km (60 mi).
Title: Modeling interannual variability of the Amazon hydroclimate
Authors: D. Medvigy, R. L. Walko, and R. Avissar: Department of Civil and Environmental Engineering, Duke University, Durham, North Carolina, U.S.A.
Source: Geophysical Research Letters (GRL) paper 10.1029/2008GL034941, 2008; http://dx.doi.org/10.1029/2008GL034941
3. Dust sources identified in Australia's Lake Eyre Basin
Covering about 1.17 million square kilometers (0.452 million square miles), Australia's Lake Eyre Basin is an important source of dust for the Southern Hemisphere. But w
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