Kasteilmiöihin

Kasteilmiöihin refers to condensation phenomena, specifically the formation of dew. Dew is water in the form of droplets that appears on thin, exposed objects, such as grass blades, leaf tips, or spiderwebs, during the cool night hours. It forms when the surface temperature of these objects drops below the dew point of the surrounding air.

The dew point is the temperature at which the air becomes saturated with water vapor and condensation begins. This typically occurs overnight as the sun's radiation ceases, and surfaces lose heat to the colder atmosphere. When the surface temperature falls below the dew point, water vapor molecules in the air lose energy and transform into liquid water, adhering to the cooler surfaces.

Factors influencing dew formation include air temperature, humidity, wind speed, and surface properties. Higher humidity means more water vapor is available for condensation. Calm conditions allow surfaces to cool more effectively and prevent the mixing of moist air with drier air. Rough or porous surfaces may hold more dew than smooth ones.

Dew plays an important role in some ecosystems, providing a crucial source of moisture for plants and small organisms, particularly in arid or semi-arid regions where rainfall is scarce. In agriculture, dew can contribute to crop hydration, though excessive dew can also promote fungal diseases. The phenomenon is a common sight in the early morning and a basic illustration of thermodynamics and atmospheric science.