Rocío

Rocío is the term for dew, the tiny droplets of liquid water that form on surfaces overnight when air near the surface cools and reaches saturation. Dew results from the condensation of water vapor in the lower atmosphere onto surfaces such as grass, leaves, or objects.

Formation occurs when the surface cools by radiative heat loss to the night sky, reducing its temperature to the dew point. Conditions favoring dew include high humidity, clear skies, light winds, and surfaces with good radiative cooling. Dew differs from frost, which forms by deposition as ice when temperatures fall below freezing; dew also differs from fog, which consists of suspended droplets in the air rather than on surfaces.

Dew can contribute small amounts of water to ecosystems and agriculture, especially in arid or semi-arid regions. It can influence plant surface moisture and microclimates, and excessive nocturnal moisture can promote fungal growth on leaves. Its daily cycle typically appears after sunset and vanishes after sunrise as surfaces warm and the air holds more vapor.

Rocío is also a Spanish feminine given name, derived from the same word; it is used in various place names and cultural references. Notably, El Rocío refers to a locality in the province of Huelva and to the annual Romería de El Rocío pilgrimage honoring Nuestra Señora del Rocío.