Choropleth Map

This map demonstrate the direct solar radiation annually. A legend is provided to show the intervals and the corresponding colors for a different amount of radiation. This max uses pixels to display its information. This is known as a raster data. Each pixel corresponds to a value representing the amount of solar radiation. Each pixel has a latitude and longitude, so it is tied into the real world surface. A collection of daily satellite readings have been compiled and entered in to display this information and determine where the concentration of radiation is. http://www.nrel.gov/gis/solar.html