Was ist eine Inversion?

Summary

This video explains atmospheric inversions, a phenomenon where the usual temperature decrease with altitude is reversed. These inversions are common in winter and can lead to weather phenomena like fog, freezing rain, and smog. The video covers various types of inversions, including ground, subsidence, and orographic inversions, and their effects on weather patterns. Inversions trap pollutants and moisture in the air, leading to poor air quality and hazardous conditions. Understanding these inversions is crucial for forecasting and managing winter weather, especially in regions prone to high pressure and low wind conditions.

Takeaways

• 😀 Inversions occur when the normal temperature decrease with altitude is reversed, leading to a stable atmosphere.
• 😀 The most common time for inversions to form is during the winter months, particularly on clear, windless nights.
• 😀 Ground or radiation inversions occur when the ground cools rapidly at night, cooling the air close to the surface and creating a temperature inversion.
• 😀 A radiation inversion can grow in height overnight and lead to foggy conditions by morning.
• 😀 Subsidence inversions form when air in high-pressure systems sinks, causing the air to compress and warm, leading to a reversal of temperature with height.
• 😀 The temperature increase in a subsidence inversion is more significant the greater the altitude from which the air sinks.
• 😀 In a subsidence inversion, the air in lower layers is cooler and moister, while the higher layers are warmer and drier.
• 😀 Orographic inversions occur when warm air is forced over mountains, cooling as it rises and warming as it descends, potentially causing precipitation such as freezing rain.
• 😀 Inversions prevent vertical mixing of air, which can lead to pollutants and moisture being trapped near the surface, especially in urban areas.
• 😀 Extended periods of inversion can result in smog formation, as pollutants accumulate in the stagnant air near the ground.

Q & A

What is a temperature inversion?

A temperature inversion occurs when the typical decrease in air temperature with altitude is reversed, meaning warmer air is found above cooler air. This disrupts the usual vertical mixing of the atmosphere and can lead to various weather phenomena.

How does a radiation inversion form?

A radiation inversion forms on clear, calm nights, especially in winter. The ground loses heat through radiation, cooling the air near the surface. This prevents air from mixing with higher layers, causing a temperature inversion close to the ground.

What weather phenomenon is typically associated with a radiation inversion?

A common phenomenon associated with a radiation inversion is the formation of fog or mist near the ground, as the cooler air near the surface causes condensation.

What causes the radiation inversion to dissipate?

The radiation inversion dissipates when the sun rises and heats the surface, warming the air close to the ground and allowing the inversion to break down.

What is an absinkinversion (sinking inversion)?

An absinkinversion occurs in high-pressure systems when air descends from higher altitudes, compresses, and warms up. This results in a temperature increase in the descending air and can create a stable atmospheric layer.

How does the height difference affect an absinkinversion?

The larger the height difference, the greater the temperature increase as the air sinks. Air descending from higher altitudes will warm more than air descending from lower altitudes, leading to a more pronounced inversion.

What is the impact of an absinkinversion on winter weather?

In winter, an absinkinversion can create a sharp temperature contrast between warm, dry upper air and cool, moist lower air. This can lead to high fog (Hochnebel) and other atmospheric phenomena.

What is an aufgleit inversion (overrunning inversion)?

An aufgleit inversion occurs when warm air moves over cooler air, forming an inversion. This can result in precipitation, particularly freezing rain if the cool air near the surface is below freezing.

Why is an inversion considered a stable weather phenomenon?

An inversion is stable because it prevents vertical air mixing. This results in stagnant air where moisture, pollutants, and other particles can accumulate, leading to phenomena like smog in urban areas.

How does a prolonged inversion impact air quality?

A prolonged inversion can trap pollutants, moisture, and other atmospheric particles near the ground, leading to poor air quality. This is particularly dangerous in urban environments where smog can form.