These files make calculations or estimations of:
- Ra, extraterrestrial solar radiation
- Rs, global solar radiation
- daily light integral, DLI
First, dli_tn/nrcc_nearby_stations.R downloads Rs data from selected stations and the Hargreaves equation estimate of Rs is calculated for comparison.
The dli_tn/tn_four_cities.R file works with temperature data from Memphis, Nashville, Chattanooga, and Knoxville, using the Hargreaves equation to make an estimate of Rs for each of those locations.
A further description of these calculations is posted at http://www.seminar.asianturfgrass.com/tn_dli_description.html.
In June 2016 I added the r/20160628_starkville.R script to calculate the estimated DLI for Starkville, MS.