An online interactive atlas to surimpose sky radiance contribution and sensitivity maps over a geo mapping background.
Sky radiance relative contribution map give the contribution of each squared km to the modeled artificial sky radiance in percentage. Basically it say from where is coming the sky radiance at the given site and observing angle for given atmospheric conditions.
Sky radiance relative sensitivity map is the contribution map divided by the installed lumen in each squared km and then renormalized so that the integral everywhere give 100%. This later map indicate how each pixel will impact the sky radiance when one remove or add a standard light fixture. So basically the highest level in that map is the first place to make change to the light fixture inventory in order to have the highest reduction.
The two maps are dependant of a set of variables:
Azimuth of the line of sight
Elevation angle of the line of sight
Aerosol optical depth
Relative humidity (not implemented yet)
Time / Date
The interface allow the selection of the relevant set of variables according to user's needs.
Both maps are standard output of light pollution model ILLUMINA.
Standard parameters set:
grid mesh : 1000 m
Ground level pressure: 101.3 kPa
Averaged Relative Humidity: 70%
Elevation angles: 15 20 30 40 60 90 (decrease of ~2X factor according to Garstang simulations toward city)