Tiny Particles, Big Storms
Aerosols are complex little particles that have an outsized impact
Aerosols range in size from a few atoms to the width of a human hair.
Through most of Earth’s history, natural aerosols such as mineral dust from deserts and sea salt have served as “condensation nuclei,” a process by which water vapor condenses to form clouds. Likewise, volcanoes have spewed aerosols into our atmosphere for billions of years.
Examples of naturally occurring aerosols include dust (left), sea spray (middle), and volcanic ash (right).
Human-caused aerosols have impacted the atmosphere
Human’s diversion of water resources and alteration of vegetation patterns have affected the amount of “natural” dust in our skies. And even though wildfires can be caused by natural phenomena such as lightning strikes, deliberate burning of crops and forests for agriculture – for example in the Amazon region – pours huge amounts of smoke aerosols into our atmosphere.
Examples of human-caused aerosols include forest burning (left), car exhaust (middle), and industrial emissions (right).
Why does this (tiny matter) matter?
The presence of aerosols in the atmosphere helps cool the planet in two ways: by directly reflecting sunlight back out into space before reaching the Earth’s surface and indirectly by promoting cloud formation.
Sounds good, right? The presence of aerosols in our atmosphere helps cooling… but it’s not that simple. Aerosols can also exacerbate climate-related impacts by altering rain patterns and contributing to stronger storms.
How will AOS help?
Aerosols are difficult to model accurately, thus understanding the intensity of aerosol effects on severe weather and climate change is challenging. AOS will enhance knowledge of aerosol characteristics, dynamics and variability in the atmosphere. This will lead to better predictive models for better planning for – and reacting to – severe weather and climate change impacts.
Learn More about Aerosols
- Chakraborty, S., Fu, R., Massie, S. and Stephens, G. (2016) Relative influence of meteorological conditions and aerosols on the lifetime of mesoscale convective systems , PNAS, 113 (27) 7426-7431, doi: 10.1073/pnas.1601935113
- NASA Earth Observatory (2010) Aerosols: Tiny Particles, Big Impact
- NASA Earth Observatory (2018) Hazardous Pre-Monsoon Dust Pollution
- Pacific Northwest National Laboratory (2020) Urban Land and Aerosols Amplify Hazardous Weather, Steer Storms Toward Cities
- United States Environmental Protection Agency (2022) Particulate Matter (PM) Basics
- World Health Organization (2022) Ambient (outdoor) air pollution
