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All-Sky Imaging System on Amazon Observation Tower

Detailed Description

The USGS High Dynamic Range All-Sky Imaging System (HDR-ASIS) is installed on top of a 148-foot (45-meter) observation tower to monitor changes in atmospheric conditions and the solar radiation available for photosynthesis.  The tower is located in the Amazon tropical forest near Santarém, Brazil.  Data from the system are being used by USGS Geographer Dennis Dye and his U.S., Brazilian and Australian collaborators to improve understanding of how photosynthesis in tropical forests responds to seasonal variations in climate. 

Tapajós National Forest, near Santarém, Pará, Brazil


Public Domain.