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Sensitivity and contribution light pollution atlas

Data usage and licence


Data usage details

Short description


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:

  • Observing site
  • Azimuth of the line of sight
  • Elevation angle of the line of sight
  • Wavelength
  • 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)
  • Azimuth angles: 0 15 30 45 60 75 90 105 120 135 150 165 180 195 210 225 240 255 270 285 300 315 330 345
  • Average Aerosol optical depth (AOD): 0.05 0.1 0.2 0.5 1.0
  • Wavelengths: 436 498 546 569 616 nm
  • 2nd scattering action radius= 4 km
  • saut_dif=71
  • r1=25 km
  • imp=0.5
  • Reflectances from: MODIS bands 1, 3, 4
  • Ground elevation from: Shuttle Radar Topography Mission (SRTM)
  • Light upward radiance from: Satellite DMSP-OLS stable lights product
  • Light photometry defined by regions with help of a local expert
  • After midnight lighting reduction by regions with help of a local expert (If applicable)

List of sites (and periods) available


  1. Observatorio del Teide (OT), Tenerife, Spain (winter (from 2009-02-26 to 2009-03-05) 2009 before and after midnight) -> will be updated with standard parameters above soon
  2. Observatorio Roque de los Muchachos (ORM), La Palma, Spain (winter (from 2009-02-26 to 2009-03-05) 2009 before and after midnight) -> will be updated with standard parameters above soon

Sky spectral radiance database

Data usage and licence


Data usage details

Short description


An collection of sky radiance spectrum acquired with SAND spectrometer on many sites worldwide.

Lamp Spectral Power Distribution Database

Undated version - august 18 2014

Data usage and licence


Data usage details

Short description


An collection various lamp spectrum and pictures.

OpenOffice spreadsheet to calculate Spectral Indices

  • MSI - Melatonin suppression index
  • IPI - Induced photosynthesis index
  • SLI - Star light index
    Indices-calculation.ods
Dernière mise à jour: 30 octobre 2017 13h17
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