Air Quality Awareness Week Day 4: Air Quality and Climate

From May 1-5, the Nevada Division of Environmental Protection (NDEP) is helping celebrate National Air Quality Awareness Week 2023! Throughout the week, NDEP is taking steps to inform all Nevadans about how air quality affects their lives. This includes sharing information and resources about air monitoring, impacts to public health, and ways to support air quality science. This is the fourth blog in this series. Read Part 1, Part 2, and Part 3.

The Earth’s climate and air quality are strongly intertwined, each having a profound effect on one another. Air pollution has a powerful impact on the planet’s climatic state, although the exact nature of this depends on the type of air pollution. Some pollutants cause large scale warming of the planet, while others cause temporary cooling, which can last days or even years.

One of the most well-known air pollutants are greenhouse gases (GHGs). These include carbon dioxide, nitrous oxide, and methane. GHGs trap heat from the Sun in Earth’s atmosphere, leading to a warming (or “greenhouse”) effect. The amount of GHGs in the atmosphere have increased dramatically since the Industrial Revolution and continue to increase to this day. According to NASA, this increase in atmospheric GHGs has caused the Earth’s average temperature to warm by 1.9°F since 1880. Common sources of GHGs include combustion engines in vehicles, coal power plants, smokestacks, and agriculture.

Aerosols are tiny atmospheric pollutants that come from burning of fossil fuels, as well as natural sources like volcanic eruptions, dust, and sea spray. The size of aerosols ranges from a few molecules in size to a few micrometers. They can be composed of a variety of materials, including sulfur, ash, salts, and pollen. Although aerosols play a key role in cloud formation, their presence in large quantities can result in haze, respiratory illness, and oftentimes a temporary cooling effect on the Earth’s climate. One recent example of this is the eruption of Mount Pinatubo in 1991, where global temperatures fell up to 1.3°F for three years following the eruption.

This warming effect can also impact the local air quality. Warming of the atmosphere and more severe heat wave events can result in higher levels of ground level ozone, or smog, in many regions. Increased global temperatures can also result in more frequent wildfires and drought, thereby increasing the amounts of particulate matter, such as dust, in the air. Higher pollen concentrations resulting from longer growing seasons can further lead to decreased air quality, and even cause health problems.