LIGHT POLLUTION & INCREASING NIGHT SKY BRIGHTNESS

NEWS: A recent study shows: ~16% increase in Artificial

ABOUT

• Light at Night (ALAN) from 2014–2022à 2% annual increase
• Light Pollution = Excessive, misdirected, or unnecessary artificial outdoor lighting

Main Causes

• Urbanisation
• Electrification
• Infrastructure growth

Key Details of the Study

Regional Variations

• High increase in: Sub-Saharan Africa, Southeast Asia
• Decrease (controlled) in: Europe → due to strict lighting regulations
• Brightest Countries: USA, China, India, Canada, Brazil
  • These countries have: High urban expansion, Extensive artificial lighting use

Rebound Effect

• Use of energy-efficient LEDs should reduce light → BUT: Lower cost → more usage of lighting
• Result: Overall increase in brightness
• This is called: Rebound Effect

Impacts of Light Pollution

• Disrupts: Circadian rhythm (body clock)
  • Melatonin hormone production
• Affects wildlife: Migratory birds get disoriented
  • Sea turtle hatchlings lose direction
• Sky glow: Makes stars invisible, Affects astronomical research
• Economic loss: Energy wastage

Key Initiatives to Control Light Pollution

• Hanle Dark Sky Reserve : India’s first Dark Sky Reserve (2022)
  • Location: Hanle, in: Changthang Wildlife Sanctuary
  • Protects: 22 km radius around Indian Astronomical Observatory
  • Objectives: Reduce light pollution, Conserve biodiversity
  • Promote: Astro-tourism
• Other Initiatives
  • Pench (Maharashtra): India’s first Dark Sky Sanctuary
  • Adoption of: Smart lighting systems