Modeling shadows with NED and solar position

Peter Sforza
Dept. of Plant Pathology, Physiology, and Weed Science
Virginia Tech

 
Equations to calculate the sun's azimuth and altitude for any date/time and geographic location were adapted to a custom script for modeling shadows using ESRI ArcGIS. Applications include estimates of photoperiod and day length, environmental modeling. An extraordinary number of systems and processes are affected by the simple fact that the Earth experiences periodic phenomenon at the planetary and solar system scales. 

QuickTime demo of shadows through the day of August 1 in the Roanoke valley.

QuickTime demo visualization of the Earth (MODIS) as North America rotates into daylight. The lights of cities at night are visible in this sequence. Resolution presented here is low. For hi-res versions contact Peter Sforza.

September 8, 2003

Comments to Peter Sforza sforza@vt.edu