Light pollution is no longer just pollution, it has become the global light pollution. A study even suggests that more than 80% of the world lives within light pollution. The sky has been light-polluted skies.
Global light-polluted skies
How can we define light pollution? Light pollution is actually triggered by the artificial lights that illuminate the world, especially at night-time. Dr. Christopher Kyba, a researcher from the German Research Center for Geo-sciences, explains that the artificial light that comes from numerous sources such as street light, billboards, and cars, significantly affects the environment and human life that are supposed to be dark at the night-time. In several countries such as Kuwait, Singapore, and Qatar even experience the brightest night skies.
A recent study even shows that almost all populations live under the light-polluted skies. The satellite reveals that 83% of the world's population live under the light-polluted skies. There are even 99% of European and American populations who live under the light-polluted skies. The light-polluted skies in the US and Europe are even 10% brighter than the natural starry level. Still according to Dr. Kyba, more or less 14% of the world do not even have any time to use their night-time vision. Meanwhile in Europe, about 37% of the population also do not use their night-time vision. The bright sky at the night-time makes their eyes stay in day time vision. This enormous numbers show that the global light pollution now becomes serious problem for the whole world.
The effects to environment
So, how the light-polluted skies affect the environment especially human being? Light pollution is quite different from air and water pollution. It does not affect the environment directly, but it will mess up the ecosystem and metabolic system of both nocturnal and non-nocturnal creatures.
Some researches shows that bright night sky that is brighter than the twilight affects the nocturnal animals. The light as well as the temperature that goes higher leads the nocturnal to get vision disorder. Meanwhile for humans, the light pollution is linked to countless diseases and sleep disorder. Human body is designed to work in the day time and get some rest at the night-time. When the night sky becomes too bright, it will confuse our body. The light will trick the body to notice the night as the day. It affects not only the night vision ability, but also the whole metabolic system. There are some hormones, for example serotonin, that are only produced during the night time while human is sleeping. The hormones are actually the natural anti-oxidant that is able to kill cancer cell and tumor. At the same time, human body is also designed to repair their system, such as their blood stream at night. It means the light pollution has increased the number of people with cancers and high blood pressure. The pollution has reaches a chronic level. Today the astronauts and satellites are even not able to see the Milky Way easily from the outer space because of the global light pollution.