Dark Sky

The September 2023 issue of LD+A has an interesting article arguing that a 180-degree cut-off for street and area lights is an inadequate requirement. The article is written by Thomas Paterson, who lays out the following arguments for a tighter beam cut-off angle, such as 150 or 120 degrees: Tolerance – A 180-degree cut-off doesn’t [...]

Last year, I wrote about the release of the first Artificial Light At Night (ALAN): State of the Science Report 2022, available here. DarkSky (formerly the International Dark Sky Association – IDA), has now released an updated version of the report titled Artificial Light At Night: State of the Science 2023 Report. It is a [...]

  Have you noticed a decline in fireflies this Summer? I have, but so have scientists. Nearly 1 in 3 firefly species in the United States and Canada may be threatened with extinction, firefly experts estimate in a recent comprehensive assessment. Surveys abroad show declines from mangroves in Malaysia to grasslands in England. New research [...]

  A new “Lights-Out” bill has been proposed in NYC’s City Council to reduce migratory bird deaths. The bill would require many privately-owned commercial buildings to reduce light at night. NYC Audubon estimates that 230,000 birds die annually in collisions with windows and brightly lit facades. The bill wouldn’t apply when people are in buildings, [...]

  A lot of research and attention has been given to how light pollution negatively impacts birds, bats, other animals, and insects. Less well known are the negative impacts of light pollution on plants. Most people have seen now bright lights at night attract moths. This can significantly change moth behavior. Artificial light at night [...]

The DesignLights Consortium (DLC) has been busy creating resources to fight light pollution. Here are three recent examples: Seven Strategies to Minimize Negative Impacts of Outdoor Light at Night. This whitepaper provides an overview of the types of light pollution that affect outdoor environments. It has high-level information for energy efficiency program staff, contractors, distributors, [...]

A group of dark sky advocates in New Zealand is actively advocating for a national law to promote dark skies and reduce light pollution. They recently published a document explaining dark skies and making the case for a national law in New Zealand. This month they launched a parliamentary petition to advocate for national legislation [...]

The DLC compiled a list and interactive maps of locations with published outdoor lighting ordinances to mitigate light pollution. These maps show states, provinces, and cities/towns, throughout Canada and the U.S., with outdoor lighting ordinances. States and provinces shaded blue have a statewide/provincewide policy. The round markers indicate cities, towns, and counties with an ordinance. [...]

It has been well documented that artificial light at night (ALAN) can disorient birds and increase bird collisions with buildings, especially windows. The reflectance of windows can lead birds to not realize that windows are solid objects to be avoided. New window film developed by the US Fish & Wildlife Service (USFWS) can prevent deadly bird-window collisions.