Most environmental pollution on Earth comes from humans and their inventions, such as cars or plastic. Today, car emissions (排放物) are a major source of air pollution leading to climate change, and plastics fill our ocean, creating a significant health issue to marine (海洋的) animals.
And what about the electric light, thought to be one of the greatest human inventions of all time? Electric light can be a beautiful thing, guiding us home when the sun goes down, keeping us safe and making our homes bright. However, like carbon dioxide emissions and plastic, too much of a good thing has started to impact the environment. Light pollution, the inappropriate use of outdoor light, is affecting human health, wildlife behavior and our ability to observe stars.
Light pollution is a global issue. This became obvious when the World Atlas of Artificial Night Sky Brightness, a computer-generated map based on thousands of satellite photos, was published in 2016．Available online for viewing, the map shows how and where our globe is lit up at night. Vast areas of North America, Europe, the Middle East and Asia are glowing (发光) with light, while only the most remote regions on Earth (Greenland, Central African Republic and Niue) are in total darkness. Some of the most light-polluted countries in the world are Singapore, Qatar, and Kuwait.
Sky glow is the brightening of the night sky, mostly over cities, due to the electric lights of cars, streetlamps, offices, factories, outdoor advertising, and buildings, turning night into day for people who work and play long after sunset.
People living in cities with high levels of sky glow have a hard time seeing more than a handful of stars at night. Astronomers are particularly concerned with sky glow pollution as it reduces their ability to view stars.
More than 80 percent of the world's population, and 99 percent of Americans and Europeans, live under sky glow.
