1. Light Pollution Emerging Tech Hour 4 Divya Jain

2. What is light pollution? The brightening of the night sky caused by street lights and other man-made sources, which has a disruptive effect on natural cycles and inhibits the observation of stars and planets.

4. Effects of Light Pollution

5. On Humans  Astronomy  Eyesight  Disability glare- reflection of light inside the eyeball. It restricts vision, causes permanent damage in the eyes, and is dangerous when driving.  Circadian Rhythm- Our internal clock  Disrupts processes in the body that the clock regulates  Causes sleep disorders, obesity, depression, diabetes  Reduces coordination and increases tiredness  Suppresses the release of melatonin  Melatonin  Hormone that makes people tired and tells the body when it is time to go to sleep  Repressing melatonin increases risk of cancer  Cost  Producing the extra light costs money and resources

7. On Animals  They use the light and dark to know when to hunt, eat, sleep, migrate, and when predators might be out  Birds  Migrating at the wrong time  Going the wrong way and getting lost  Colliding with buildings and dying  1954 Warner Robins Air Force Base, Georgia- in two days over 50,000 birds died  Sea turtles

8. On Environment  Plants  Flowering and pollination  Tree branches in winter  Animals  Lose their homes when branches break  Plant dependent animals die  Predators lose their source of food  Food web  Energy wastage  1/3 of all lighting is wasted  30 million barrels of oil an d8.2 million tons of coal in the United States alone  $2 billion  More Pollution  Air and water pollution  Carbon footprint  Global warming

9. What we can do?  Energy efficient light bulbs  Shield lights properly  Support organizations that work to improve light pollution  Inform others to do their part  Turn off the lights