Excessive, misdirected, or obtrusive (usually outdoor) light.
Brightening of the night sky that inhibits the observation of stars and planets, caused by street lights and other man-made sources.

Various Night Skies

Good outdoor lighting should:
Optimize visibility at night for what we want lit
Minimize energy consumption
Minimize impact on the environment and ourselves
Minimize glare
Minimize light trespass

Light that can be found rude, obstructive, or oppressive by the non-owners of the light

3 main kinds
Glare- light from unshielded sources.
Light trespass (AKA spill light)- unwanted light that enters one’s.
Skyglow- the combination of all the reflected light and upward-directed (unshielded) light escaping up into the sky (and for the most part, unused), causing the glow effect that can be seen over populated areas.

Other types of pollution
Uplight- wasted light that goes directly up into the night sky, is "lost in space”, and serves no useful purpose.
Clutter- bright, confusing, ugly and excessive groupings of light sources, commonly found in over-lit urban areas.

Various Lighting Techniques

Light Pollution Diagram

Glare

Glare

Glare

Light Trespass

Light Trespass

Ineffective Lighting

Improving Lighting Designs

Minimizing Light Pollution

Improving Street Light Design

Improving Energy Efficiency

More than half of the world’s population now living in cities
3 out of every 4 people in cities have never experienced pristinely dark skies

http://www.lightpollutionmap.info/#zoom=4&lat=
5759860&lon=1619364&layers=B0TFFFTT http://www.youcanseethemilkyway.com/lightpollution/ http://www.blue-marble.de/nightlights/2012

Light Pollution Increase (1950s-Projected 2025)

Squid Fisheries

Light pollution wastes
Light pollution consumes
Light pollution pollutes
Light pollution harms
Light pollution threatens
Light pollution destroys

How Light Pollution Affects Animals

Affect on Circadian Rhythm

Turn Out the Lights

Ashy Storm Petrel

Sea Turtle Cartoon

Baby Turtles

http://www.tourdeturtles.org/flash/LightPollution.swf

Loss/endangerment of species
Health-related issues
Depletion of resources

Shielding lights properly
Only using light when and where it is needed
Only using the amount that is needed
Making sure exterior lighting only light the ground beneath them
Remember: need, intensity, duration, and spectrum

Articles http://www.globeatnight.org/light-pollution.php
http://ngm.nationalgeographic.com/2008/11/lightpollution/klinkenborg-text http://www.physics.fau.edu/observatory/lightpol.html
http://www.starrynightlights.com/lpIndex.html
http://www.actionbioscience.org/environment/longcore_ri ch.html

Images http://wolvesonceroamed.files.wordpress.com/2012/03/nig ht-sky.jpg
http://www.penny4nasa.org/wpcontent/uploads/2013/07/asc-csa.gc_.ca-efficientlighting.gif
http://www.nature.nps.gov/night/assets/images/outdoorlig hts.jpg
http://www.physics.fau.edu/observatory/lightpolsecurity.html

Images https://m1.behance.net/rendition/modules/56652753/disp/
712f602803941d252f4f6122b3003654.jpg
http://a.static.trunity.net/files/141201_141300/141277/circ adian_rhythm.jpg
http://physics.fau.edu/observatory/Images/parkinglot2_sm
.jpg
http://www.penny4nasa.org/wpcontent/uploads/2013/07/wired.com-light-pollution.jpg

Images http://old.nightwise.org/lot04608.JPG
http://old.nightwise.org/DSC07928.JPG
http://calgary.rasc.ca/lp/Images/s_full_cutoff_roadwa y_lights_large.jpg
http://www.alternativesjournal.ca/sites/default/files/a rticle/Light_Pollution_Diagram_680px.jpg

Images http://scienceblogs.com/startswithabang/files/2009/09/squ id-fisheries.jpg
http://www.delmarfans.com/images/content/educate/Light
_Pollution_Article/Unshielded-Light-Waste-Large.jpg
http://bloximages.newyork1.vip.townnews.com/sustainabl ecitynetwork.com/content/tncms/assets/v3/editorial/9/71/
97155ce4-3be9-11e1-a993-
001a4bcf6878/4f0cd500952f6.image.jpg

Images http://s15.photobucket.com/user/Chance2795/media/seat urtlecartoon.jpg.html
http://www.mesa.edu.au/turtles/images/cut_the_glow.jpg
http://www.earthrangers.com/content/wildwire/protect_bir ds_light_pollution.jpg
http://irregulartimes.com/wpcontent/uploads/2009/08/ashystormpetrellight.jpg