Wärmeschichten

Wärmeschichten, also known as thermal layers or temperature inversions, are a phenomenon in atmospheric science. They occur when a layer of warmer air is situated above a layer of cooler air. This is the reverse of the typical atmospheric profile where temperature generally decreases with altitude.

These inversions can form in several ways. Radiational cooling is a common cause, where the ground surface cools rapidly at night, chilling the air directly above it. This cooler, denser air is trapped beneath a layer of warmer air, often due to calm winds or a lack of atmospheric mixing. Advection inversions happen when warmer air moves horizontally over a cooler surface, like warm air moving over snow or cold water. Subsidence inversions are formed by descending air in high-pressure systems, which compresses and warms as it sinks.

Wärmeschichten can have significant impacts. They can trap pollutants, fog, and dust near the ground, leading to poor air quality and reduced visibility. This trapping effect is particularly noticeable in urban areas. In meteorology, the presence of a Wärmeschicht can influence weather patterns, affecting cloud formation and precipitation. They are also important considerations in aviation, as pilots may encounter abrupt temperature changes and turbulence when passing through them. The stability of the atmosphere is significantly altered by the presence of a Wärmeschicht, hindering vertical air movement.