Solarradiation.m is used to calculate the solar radiation for a digital elevation model integrated over one year. Radiation is calculated depending on latitude, elevation, horizon shading, slope, aspect, time of year and hour of the day (day length/season) and ground reflectance.
Temporal resolution of radiation calculation over sunshine hours can be set freely (1 hour default).
The script follows the approach by Kumar et al (1997). Simple unweighed 4 nearest neighbour gradient calculation is used and relief shading is not accounted for.
Reference: Kumar, L, Skidmore AK and Knowles E 1997: Modelling topographic variation in solar radiation in
a GIS environment. Int.J.Geogr.Info.Sys. 11(5), 475-497