skyerne

Skyr, or skyerne in Danish and Norwegian, refers to the clouds—the visible masses of condensed water droplets or ice crystals suspended in Earth's atmosphere. In everyday use, skyerne collectively describe the cloud cover observed from the ground and in the sky, and they play a central role in weather and climate description.

Formation and composition: Clouds form when moist air rises, expands as ambient pressure decreases, and cools to the dew point. Water vapor condenses on aerosol particles to create tiny droplets, or, in colder regions, ice crystals. The mixture of liquid and/or ice determines a cloud’s appearance and behavior. Temperature, humidity, and vertical motion influence cloud development and persistence.

Classification: Clouds are commonly grouped by altitude and form. High clouds (above about 6,000 meters) include cirrus, cirrostratus, and cirrocumulus. Middle clouds (roughly 2,000 to 7,000 meters) include altostratus and altocumulus. Low clouds (below about 2,000 meters) include stratus, stratocumulus, and nimbostratus. Clouds with vertical development, such as cumulus and cumulonimbus, can extend from near the surface to high levels and are associated with a range of weather, from fair skies to thunderstorms.

Weather and climate role: Clouds influence weather forecasting by indicating atmospheric stability and moisture. They also affect the Earth’s radiative balance by reflecting sunlight and trapping infrared radiation; the overall climatic impact depends on cloud type, altitude, thickness, and phase (liquid or ice).

Observational notes: Sky conditions are commonly described by cloud type, coverage, and altitude estimates, aiding meteorology, aviation, and outdoor planning.