Light Pollution

Glare

Light trespass

Sky glow

Energy waste

Clutter

Quantifying Light Pollution Worldwide

Defense Meteorological Satellite Program (DMSP) USAF

Satellite and ground based observations.

P. Cinzano, F. Falchi, C. D. Elvidge

U of Padova Dept of Astronomy

66% of the US population and 20% of the world’s population can no longer see the Milky way.

99% of the population in the lower 48 and the EU live in areas where the night sky is above threshold set for polluted status.

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Light PollutionLight Pollution

Outdoor lighting currently stands as one of the most inefficient uses of energy today.

30 to 50% of all light pollution is produced by roadway lighting that shines wasted light upwards and outwards.

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Toronto 2003 – Sky Glow & Glare

During Blackout After Blackout

Skyglow

Honolulu, HICan it be fixed? Yes.How? With ordinances & one light at a time.

Courtesy M Donohue

Sky glow over Haleakala.

Note Hnl lights in NW& darkness in SE

Ranks as 5th

best observatory in the world

The Cost of The Cost of Throwing Away ElectricityThrowing Away Electricity

The USA spends over $2 billion per year in energy costs from wasted light at night.

Waste:

= 6 million tons of coal or

= 23 million barrels of oil per year

Greenhouse gasses produced add to global warming.

55% from coal

22% from nuclear

10% from natural gas

10% from hydropower

2% from oil (Hawai’i 90%)

1% from other sources

US Power Sources

Light & Human health Circadian rhythmsMelatonin and the pineal glandNewly discovered RGC’s (Berson-2002)

Blue light sensitive 464 – 480 nmTrigger SCN – clock center – non visual

Rat studies (Blask – Basset Research Center, Cooperstown, NY)LAN reduces mlt. And increases growth rates of human

breast cancer cells implanted in ratsDarkness at night – high mlt.; low cancer growth rates

Human studies (Blask – 2004)Blood from humans exposed to LAN – low mlt; high cancer cell growthBlood from humans exposed to darkness – high mlt; low ca growth

Epidemiology – cancers in shift workers (Harvard nurses health study)(Stevens, Schernhammer)

Higher rates of breast and colorectal cancers in shift workers

Paper summarizingcurrent literature linking LAN to breastand colorectal cancer.

Medical HypothesesOct. 2004

Effects of Artificial Light at Night on Ecosystems (photopollution)

Paper summarizingcurrent literature linking LAN to breastand colorectal cancer.

Medical HypothesesOct. 2004

Lighting and CrimeLighting and Crime

Most crimes take place during the day

Two congressional crime task forces (1979 & 1997) found no relationship between lighting and crime. The studies that say there is a relationship are not controlled studies

“There are simply no good scientific studies that convincingly show the relationship between lighting and crime.” - (Ref - IDA information sheet 42; 4/98)

In defense of low pressure sodium lights on MauiGood for astronomersGood for human health – no mlt. SuppressionGood for ecosystems

Good FCO Lighting In All Places

Recessed canopy lights

15 50watt hpslamps 10 ft high,4000 lumens each,21 ft apart.

60,000 lumens oflight surrounding thebldg.

Overkill

Good FCO Lights

Opaque cover diffuseslight better

Everybody Wins With Everybody Wins With Good LightingGood Lighting

Less glare, light trespass & sky glow

Restores dark skies for stargazing

Good for human health & ecosystems

Prevents the pervasive spread of light pollution

Preserves the night skies for our children

Everybody Wins With Everybody Wins With

Good LightingGood Lighting

• Important to human health to sleep in darkness.

• Important to health of ecosystems to minimize exposure of plants and animals to light at night.

Light pollution is the easiest kind of pollution to fix.

Reduce it, shield It, & shine it down.

Light the subject & hide the source.

Follow IESNA rec. levels.

Use IESNA mins as maximums when can.

Design for low impact lighting.