Light Pollution Annual Range

Risksv0

Responsible:Niccolò Calandri

Light Pollution Annual Range

Overview

The Light Pollution Annual Range measures the pixel-wise difference between the maximum and minimum nighttime light intensity recorded over a one-year period. Expressed in nanoWatts per square centimetre per steradian (nW/cm²/sr), this indicator captures the seasonal variability of artificial nighttime illumination.

Formula:

LP_range = LP_max − LP_min (pixel-wise, annual basis)

Interpretation of values:

High range values → strong seasonal lighting variation; seasonal tourist areas, industrial zones with cyclic activity, holiday illumination
Moderate range values → moderate variation; residential areas with variable lighting, peri-urban zones
Low range values → stable illumination; established urban centres with permanent lighting

The indicator is useful for:

Identifying seasonal patterns in artificial lighting
Monitoring light pollution reduction policy effectiveness
Assessing seasonal tourism impact on the nocturnal environment
Characterising the stability of the luminous footprint

Calculation Methodology

Data: VIIRS Day/Night Band (DNB) Monthly Composites (NOAA), available on Google Earth Engine. VIIRS sensor on Suomi NPP and NOAA-20 satellites, resolution ~750 m → ~500 m in monthly composites.

Data acquisition — VIIRS DNB monthly composites over the year (12 months)
Quality filtering — removal of pixels affected by moonlight, aurora, artefacts
Pixel-wise max and min extraction — across 12 monthly composites
Range calculation — LP_range = LP_max − LP_min
Reprojection to EPSG:3857 at 30 m resolution

Data Sources

Code	Name	Provider	Resolution	Availability
`WRD_VRDNB_99`	VIIRS DNB Monthly Composites	NOAA/NASA	~500 m	2012 — present

Technical Notes

Native VIIRS DNB resolution ~750 m; reprojected to 30 m for consistency
Sensitive to occasional events (fires, festivals) creating radiance spikes
Monthly composites already filter most moonlight and cloud noise
In areas with very low illumination, the range may not be meaningful

References

Elvidge, C.D. et al. (2017). Int. J. Remote Sensing, 38(21), pp. 5860–5879.
Falchi, F. et al. (2016). Science Advances, 2(6), e1600377.
Kyba, C.C.M. et al. (2017). Science Advances, 3(11), e1701528.

Data Sources & References

Sources

WRD_VRDNB_99

Methodology

Il range dell'inquinamento luminoso viene calcolato a partire dai compositi mensili VIIRS Day/Night Band (DNB) prodotti da NOAA. Per ciascun mese dell'anno vengono selezionati i compositi mensili, filtrati per qualità (rimozione di artefatti da luce lunare e aurora). Per ciascun pixel, vengono estratti i valori massimo e minimo di radianza notturna sui 12 compositi mensili, e il range è calcolato come differenza (LP_range = LP_max − LP_min). Il raster risultante viene riproiettato a 30 m di risoluzione.

Light Pollution Annual Range

Overview

Formula:

LP_range = LP_max − LP_min (pixel-wise, annual basis)

Interpretation of values:

High range values → strong seasonal lighting variation; seasonal tourist areas, industrial zones with cyclic activity, holiday illumination

Moderate range values → moderate variation; residential areas with variable lighting, peri-urban zones

Low range values → stable illumination; established urban centres with permanent lighting

The indicator is useful for:

Identifying seasonal patterns in artificial lighting

Monitoring light pollution reduction policy effectiveness

Assessing seasonal tourism impact on the nocturnal environment

Characterising the stability of the luminous footprint

Calculation Methodology

Data: VIIRS Day/Night Band (DNB) Monthly Composites (NOAA), available on Google Earth Engine. VIIRS sensor on Suomi NPP and NOAA-20 satellites, resolution ~750 m → ~500 m in monthly composites.

Data acquisition — VIIRS DNB monthly composites over the year (12 months)

Quality filtering — removal of pixels affected by moonlight, aurora, artefacts

Pixel-wise max and min extraction — across 12 monthly composites

Range calculation — LP_range = LP_max − LP_min

Reprojection to EPSG:3857 at 30 m resolution

Code

Name

Provider

Resolution

Availability

WRD_VRDNB_99

VIIRS DNB Monthly Composites

NOAA/NASA

~500 m

2012 — present

Data Sources & References

Sources

WRD_VRDNB_99