Small aerosols refer to tiny particles or droplets suspended in the air, such as dust, smoke, or mist. These particles can be produced by natural processes like volcanic eruptions or human activities like burning fossil fuels, agricultural practices, and industrial processes. Small aerosols play an important role in Earth's climate system, as they can scatter sunlight back into space, reflecting heat away from the planet. They also act as cloud condensation nuclei, which help form clouds that can have both cooling and warming effects on the atmosphere.