Modelling Variations in Solar Irradiance

Abstract

The sun is the main source of energy for the Earth, and governs most atmospheric, biological, and environmental processes. Due to fluctuating composition, thickness, and pollution, solar radiation can be scattered or absorbed in the atmosphere affecting the amount received by Earth’s surface as these interactions vary. Solar irradiance is the total amount of radiation reaching Earth’s surface, in watts per square meter, from the sun. Irradiance can be measured with a pyranometer, and is governed by the solar constant, atmospheric thickness, atmospheric composition, and beam dilution. In this project we have modeled the solar irradiance expected from a plane-parallel atmosphere to determine the sensitivity of the PYR-BTA Vernier Pyranometer to variations in atmospheric transparency with the intent to quantify pollution levels in urban areas. We used the solar irradiance data captured from MacEwan University to model the partial solar eclipse of August 21, 2017.