Average nocturnal light emissions – 2020 condition

The map shows the nocturnal emissions of light in Flanders observed from space. The Suomi National Polar-orbiting Partnership satellite flies over Flanders after midnight and has a very sensitive sensor (Visible/Infrared Imaging Sensor or VIIRS). Data from this sensor are processed by NASA into global nocturnal light emissions (Román, M.O., Wang, Z., Sun, Q., Kalb, V., Miller, S.D., Molthan, A., Schultz, L., Bell, J., Stokes, E.C., Pandey, B. and Seto, K.C., et al. (2018). NASA's Black Marble nighttime lights product suite. Remote Sensing of Environment 210, 113-143. doi:10.1016/j.rse.2018.03.017). Only high-quality data was used without the influence of atmospheric disturbances, terrain and vegetation disturbances, moonlight, stray light, clouds and snow. This processing takes place on a daily basis. The annual map is based on the annual average of the daily maps, excluding outliers and observations on snow days. The units of the card are Watt/cm2/steradians. This is the power per surface area per angle of space. The map shows the average value of the light masses for the Flemish Region for the reference year 2020.