Air Pollution and Climate Change
Air pollution affects Earth’s climate. However, not all types of pollutants have the same effect. There are many different types of air pollution. Some types cause our planet to warm at a faster rate. Others cause the rate of global warming to slow down by causing temporary cooling. Read on the learn more about pollutants that cause warming and those that cause cooling.
Some air pollutants cause more global warming
Air pollution includes gases such as carbon dioxide, methane, and nitrous oxide. These are greenhouse gases. Greenhouse gases don’t make up a large percentage of Earth’s atmosphere, but even in small quantities they have a profound effect on global climate. Greenhouses gases are mostly responsible for the increase in global surface air temperature of about 0.6º Celsius (1º Fahrenheit) over the past century and scientists project that much more warming will likely happen during the next century.
Greenhouse gases cause global warming by trapping solar radiation in the atmosphere. Greenhouse gases are a natural part of Earth’s atmosphere, but in the last 150 years or so, the amount of greenhouses gases in our atmosphere has increased significantly because of an increase in the amount of car exhaust and pollutants released from smokestacks at factories and power plants.
Some air pollutants slow down global warming
Cars, trucks, and smokestacks also release tiny particles into the atmosphere. Tiny particles, called aerosols, range in size from 10 nanometers to more than 100 micrometers in diameter. They can be composed of various substances such as mineral dust, sulfates, sea salt, or carbon. They can occur naturally in the atmosphere, for instance released by erupting volcanoes or from wildfire smoke, but air pollution released by burning of fossil fuels also contributes the tiny particles to the atmosphere. Aerosols have an impact on climate. While different types of aerosols act differently in the atmosphere, the overall effect of aerosols is cooling.
Greenhouse gases remain in the atmosphere for years and cause warming. Computer models indicate that, worldwide, sulfates and other particles cause about half as much cooling as greenhouse gases cause warming.