Answer: Precipitation
Explanation:
Airborne particulates, or particulate matter, are compounds of small size that can mix with the lower part of the atmosphere, such as dust, soot, smoke, dirt and some liquid droplets. The size of the particulates ranges from 0.1 µm to 10 µm, which is called an aerodynamic diameter. This size allows particulates to stay in suspension in the troposphere.
Because of their varied nature, temperature does not remove all the types of particulates from the air. Photosynthesis is a process that removes CO₂ from the atmosphere, but CO₂ molecules are too small to be considered a particulate. CO₂ molecules are disolved in the atmosphere.
Precipitation removes the particulates from the air because it facilitates dissolution with water. In several countries, like Australia, the US or Mexico, still air and inversions (where cold air is trapped below warm air) produce a slower removal of particulates than in humid regions due to the limited precipitation. Moreover, arid conditions (rises of temperature) can increase the probability of wildfires with the concomitant raise in the particulates concentration (such as ashes and soot).
