authority: folia
slug: nightlights
name: Nighttime Lights
domain: anthroposphere
subdomain: urban
authority_id: folia:nightlights
aliases:
  - night-lights
  - ntl
  - viirs-dnb
external_ids:
  cf_standard_name: null
canonical_units: nW cm-2 sr-1
external_validations:
  product:
    id: viirs-vnl-v2
    docs_url: https://eogdata.mines.edu/products/vnl/
  product_alt:
    id: dmsp-ols-archive
    docs_url: https://www.ngdc.noaa.gov/eog/dmsp.html
  product_alt2:
    id: black-marble-vnp46a2
    docs_url: https://blackmarble.gsfc.nasa.gov/
description: |
  Upwelling top-of-atmosphere radiance observed at night, captured by
  the VIIRS Day/Night Band (Suomi-NPP, NOAA-20/21) and historically by
  the DMSP Operational Linescan System. Reported in nanoWatts per
  square centimetre per steradian. Flagship products: VIIRS VNL V2
  annual composites (Earth Observation Group, Colorado School of
  Mines), NASA Black Marble VNP46A2 (BRDF/atmosphere-corrected daily),
  and the NOAA NCEI DMSP-OLS historical archive (1992-2013). Widely
  used as a proxy for urbanization extent, electrification access,
  economic activity, and as a near-real-time indicator in
  conflict-zone monitoring and disaster impact assessment.
theme: infrastructure
consumed_by: []
produced_by: []
demos: []
status: documented
sources:
  - https://eogdata.mines.edu/products/vnl/
  - https://www.ngdc.noaa.gov/eog/dmsp.html
  - https://blackmarble.gsfc.nasa.gov/