The authors of this study aimed to analyze how solar radiation--insolation--can be utilized in farming and agriculture. Insolation has a great effect on an ecosystems "air and soil heating, evapotranspiration, photosynthesis, winds, and snow melt" and thus is relevant in studying an ecosystem's primary productivity (Fu & Rich). The authors cited that early models created using ArcGIS software, such as the SolarFlux model, had been used for many years in this realm of research but posed logistical problems such as the need for high-cost GIS software. Digital Elevation Modeling was being used to analyze insolation's and topography's effect on soil temperatures.
Fu and Rich developed their insolation-temperature maps with topography, elevation, canopy cover, and surface orientation all taken into account. Their research found that "maximum daily soil temperature
is determined by heating during the day, and this is strongly influenced at the local
insolation," leading them to conclude that solar radiation has the strongest influence on the daily temperature increase in an area (Fu & Rich).
Fu, P., & Rich, P. M. (2002). A geometric solar radiation model with applications in agriculture and forestry. Computers and electronics in agriculture, 37(1), 25-35.