1. Impacts of Artificial Light On Our Ecosystem
Joe Frannea - Volunteer
Southern Arizona Chapter of the
International DarkSky Association
Dec 2015

2. International DarkSkies Association “IDA”
Educators - Activists
Advocate Natural Skies
Since Five Staff - 10,000 Volunteers
Not Against Lights…
Just Keep Them On The Ground!
“Start NO Wars”

3. The World is Very Different at Night
More animals are nocturnal than diurnal
Natural darkness as important as daytime
All living things have biological cycles (circadian clock/rhythms, free run at hrs)
Artificial Lights - only past 125+ years
Electric Light Bulb
Thomas Edison 1880
George Westinghouse
Electricity Transmission

4. The USA at Night
$2B/Yr.
Wasted!
More Like Daytime

5. More Astronomers & Scopes in Southern AZ
One Reason to Care…
More Astronomers & Scopes in Southern AZ
$250M+
Optics & Astronomy
Business AZ/Year
MMT – Mt. Hopkins

6. Another - Plants All Living Things have Biological Clocks
They Need Natural Dark/Light Cycles

7. Amount of Light Required Varies by Plant
One study showed a one second light at night caused the plant not to bloom
Some growers or florists control the Light to delay of force blooms

8. It’s Not East to Survive, and We are Not Helping!
Another - Wildlife
It’s Not East to Survive, and We are Not Helping!
When to mate, migrate, hibernate
Food sources for migration (early blooms)
What season is it, natural environment
Interactions, other animals, plants
Avoid lit areas, taking their habitat
Our lifestyle seems to trump their habitat
(landscape lighting, floodlights, lit bridges/buildings, etc.)

9. Artificial Lights Impact:
Mammals - Bats
Migrating Birds & Collisions Lit Buildings
Sea Turtles & Hatchlings
Frogs, Toads, Lizards, Snakes
Fish, Plankton
Insects, Moths, Fireflies
Outdoor Lights Attract Many Animals
due to the Food Chain Hierarchy

10. Can Be a Carcinogen –Shift Workers
Another - Human Health
EPA
Light Pollution is a Pollutant
AMA (2012)
Excessive Nighttime Lighting Disrupts Essential Processes and can Create Potentially Harmful Health Effects and Hazardous Situations.
Can Be a Carcinogen –Shift Workers

11. Red
Dark Sleep Is:
Critically Important for Proper Levels of Melatonin Production

12. Human Eye Sensitivity
Rods – Night Time
Cones – Day Time

13. Good Visibility at Night It’s All About Contrast
White on Black vs White on White

14. Physical Effects of Light
Circadian Rhythm (since beginning of time)
This Must Be Reset Daily (not exactly 24 hours)
The Light – Dark Cycle Resets It
Melatonin Production Produced Only at Night – Dark Environment
A Small Amount of Light Stops It Immediately
(especially blue/white light)
Light Exposure Can Elevate
Heart Rate, Core Body Temp., effect Cortisol production

15. Circadian Rhythm Sleep Disorders
(most documented)
Most Common is Shift-Work Disorder (15M people)
More Sleep Problems
Fatigue
Forgetfulness
Performance Problems
Gastrointestinal Problems
More Accidents and Injuries
Risk of Cardiovascular Disease
Type-2 Diabetes
Some Types Cancer

16. they still work & are very inexpensive
Safety
Reduce Glare
Light for the Task
Use Motion Sensors
Use Flash Lights
they still work & are very inexpensive

17. Security More Crimes Occur in Daytime vs
Security More Crimes Occur in Daytime vs. Night time Some People Believe…
Dark Yields
Less:
Good Lighting
Yields Less:
Theft
Vandalism
Graffiti
Drug Deals
Prostitution
Attacks
Robbery
Rape
No Statistical Evidence to Support More or Less Light Reduce Crime
Small Studies DO Not Translate to Larger Areas – Measures are Difficult

18. Glare, luminance overload,. bad transition lighting
Glare, luminance overload, bad transition lighting A Much Too Much Light Better design!

19. Brighter Does Not Mean Safer
Unshielded
Good visibility is the goal.
Photos © George Fleenor
Add a Shield
© International Dark-Sky Association
“Movie Theater Effect”

20. Brightly Lit Walkway With Shadows

21. Person Steps Into a Shadow – False Security

22. Importance of Shielding

23. Outdoor Lighting Codes
Pima County & City of Tucson
Some of the Important Codes
Total Lumens (L) Allowed based on Lot Space Occupied
- Total Light for 1/3 acre 18,000 L (lot 100’ x 135’)
- Unshielded Portion for 1/3 acre (E3 zone): 3,600 L
Maximum Lumens from an Unshielded Fixture: 3,000
Unshielded Floods Must Be aimed 45 degrees or lower
Color Temperature of bulb Must Be 3500K or lower
Commercial Unshielded Lights Must Be off by 11 PM
An Unshielded Light Means NO Light Above the Horizontal
Note: 60w incandescent. lamp about 800L, 65w fluorescent 3,900 L,
150w halogen 2,400 L , Streets: 70w HPS 6,700 L,, 100w metal-halide 8,500 L

24. Summary Responsible Lighting
Only When Needed & Control It Down
(no light above the horizontal)
Only On When Needed
(use motion detectors)
Avoid Obtrusive Light & Glare
(more light is not better, often worse)
Save Energy, Use Energy Efficient Bulbs
(CFLs and LEDs)

25. It’s Easy to HELP. . . Just Share Your Knowledge
Joe Frannea
Web: sa-ida.org