Molnpartiklar

Molnpartiklar, or cloud particles, refer to the minuscule solid or liquid particles that form clouds in Earth's atmosphere. These particles are not water vapor, which is a gas, but rather condensed water droplets or ice crystals. The formation of cloud particles begins with the process of condensation, where water vapor in the air cools and changes into a liquid state. This cooling typically occurs as air rises and expands in the atmosphere. However, water vapor does not spontaneously condense into droplets or ice crystals. Instead, it requires a surface to condense upon.

These surfaces are provided by atmospheric aerosols. Aerosols are tiny solid or liquid particles suspended in the air, originating from various sources such as dust, sea salt, volcanic eruptions, and pollution from human activities. When air becomes saturated with water vapor and cools sufficiently, water vapor will condense onto these aerosol particles, forming cloud condensation nuclei (CCN) if the particle is soluble or ice nuclei (IN) if it promotes ice formation. The size of these cloud particles is incredibly small, typically ranging from a few micrometers to tens of micrometers in diameter. Billions of these tiny particles coalesce to form visible clouds. The type of cloud formed, whether it's a stratus, cumulus, or cirrus cloud, depends on factors like atmospheric temperature, humidity, and air movement, which in turn influence the size, composition, and density of the cloud particles.