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Centaur
2019-Jul-30, 09:37 PM
Chicago Tribune - Today: https://www.chicagotribune.com/news/breaking/ct-bright-city-lights-worse-for-west-nile-birds-20190730-r6k4nxj3hzhsthyqcn57v7o23m-story.html

Reality Check
2019-Jul-31, 04:18 AM
Chicago Tribune - Today: https://www.chicagotribune.com/news/breaking/ct-bright-city-lights-worse-for-west-nile-birds-20190730-r6k4nxj3hzhsthyqcn57v7o23m-story.html
An interesting news report.
The story is predominantly about a possible effect of the new LED streetlights on birds with the West Nile virus. A study found that sparrows with the virus when "exposed to artificial light stayed sick with West Nile an average of two days longer than the control group". That makes it more likely that the West Nile virus can spread to people. There is some thought that this conversion will increase light pollution. However the Chicago Department of Transportation stated that the new lights are designed to reduce light pollution by focusing light downward. The LEDs are also “soft white” lights that meet the requirements of the International Dark-Sky Association.
The conversion will be monitored: Cameras in the corn: Adler space balloon project aims to map Chicago light pollution (http://www.chicagotribune.com/entertainment/museums/ct-ent-adler-balloon-chicago-light-pollution-map-0905-story.html)

Jerry
2019-Sep-18, 01:27 PM
This article is junk science - politicized science that extrapolates from a cleaver but tenuous study with an unjustified leap. The study did not compare the relative stress of mercury vapor to LED lights on the sleep patterns of sparrows, but of light pollution in general.
There is no scientific reference for the assertion that 'yellow light' is less stressful than LED lighting; and the real result of the light change could be the opposite.
As far as the effect on humans, the frequencies chosen to create LED light provide the human eye with much more useful information with a fraction of the energy. Light at night reduces both accidents and crime - there are real numbers on that.

Jerry
2019-Sep-18, 01:29 PM
This article is junk science - politicized science that extrapolates from a cleaver but tenuous study with an unjustified leap. The study did not compare the relative stress of mercury vapor to LED lights on the sleep patterns of sparrows, but of light pollution in general.
There is no scientific reference for the assertion that 'yellow light' is less stressful than LED lighting; and the real result of the light change could be the opposite.
As far as the effect on humans, the frequencies chosen to create LED light provide the human eye with much more useful information with a fraction of the energy. Light at night reduces both accidents and crime - there are real numbers on that.