It may be invisible to the naked eye, but the air is full of particles of salt, smoke, dust, and other microscopic gunk.
NASA has recently released a stunning but scary visualization of the plumes of aerosols swirling everywhere in the world. Using satellites and ground sensors, the agency was able to create a map that shows clouds of particles of matter floating around the globe and puts into perspective how pervasive they have become.
What Are Aerosols?
Aerosols are ubiquitous specks of liquid or solid found in the air that drift from the atmosphere and back to the ground. These particles range in size from a few nanometers to tens of micrometers.
Aerosols are everywhere — they can be found over oceans and seas, forests, deserts, cities and rural areas, mountains, and ecosystems in between. Humans breathe them in when they are in the ground or interact with the climate when floating in the atmosphere,
These specks of solid and liquid are produced and emitted into the air by a variety of natural and man-made phenomena. NASA claims that majority of the aerosols in the air or about 90 percent have natural origins.
Sea salt and dust are the most common aerosols around the world. Wind-driven spray from ocean sends microscopic drops of sea salt into the air while sandstorm lifts up particles of mineral dust from the desert to the atmosphere.
Wildfires, like the ones currently raging across Canada and United States, also contribute to the clouds of aerosols in the air and the atmosphere. In the visualization below, the areas in red represent black carbon particles.
Blue represents sea salt aerosol while purple shows clouds of dust.
If you have ever watched smoke billowing from a wildfire or dust blowing in the wind, you've seen aerosols. This visualization uses @NASAEarth satellite data to show the expansive view of the mishmash of particles that dance & swirl through the atmosphere https://t.co/kSeB1jWjmP pic.twitter.com/I9BKFPik01 — NASA (@NASA) August 24, 2018
The remaining 10 percent of the aerosol caused by man-made events are often found in the air in urban and industrial areas. They come from automobiles, power plants, incinerators, fireplaces, candles, and others. Deforestation, excessive irrigation, and overgrazing also contribute to the problem.
NASA warns that the visualization "is not a direct representation of satellite data." The agency also added that some aerosols are causing very real problems on the ground, namely the twin tropical cyclones Soulik and Cimarron in South Korea and Hurricane Lane in Hawaii.
How Aerosol Affects The World
Aerosols have direct and indirect effects to the planet. One direct effect of these ubiquitous particles of matter in the air and the atmosphere is poor air quality recently experienced in cities such as Seattle and Portland.
The indirect effect is the particles' interaction with the climate by scattering or absorbing light and changing the planet's reflectivity. Particles of aerosols are said to reflect about a quarter of the sun's energy back to outer space or absorb sunlight in varying degrees. In contrast to the greenhouse effects of atmospheric gases, aerosol can cool the atmosphere.