A temperature inversion occurs when a layer of warm air develops on top of a layer of cooler air. This warm layer, the inversion, acts like a cap that seals the cooler atmosphere beneath it. If the fast-moving air of an updraft has a hard time breaking through a temperature inversion, imagine how much harder it is for the atmosphere to churn itself up when one of these events occurs during the winter months.
There are several different kinds of inversions you can encounter when it gets chilly. Each type of inversion comes with its own set of inconveniences and hazards. Cold air is dense. It drains from higher elevations to lower elevations and hugs as close to the ground as possible.
This makes valleys especially vulnerable to inversions in the winter. These inversions occur when cold air gets trapped in the valley and a layer of warm air seals it from above. The end result is a spell of nasty, stagnant air that can be extremely hazardous to the health of anyone in the region. The stale air of an inversion allows for the buildup of pollutants created by vehicles, factories, fireplaces, and wildfires.
Image: Unsplash. Usually, the higher the altitude, the lower the temperature of the air. Temperature inversion is a meteorological phenomenon that develops when cool air is trapped at the ground under a layer of warm air.
There are four types of temperature inversions :. The warmer air in a temperature inversion acts as a lid, trapping pollutants near the ground and making them unable to disperse until the weather changes. However, sometimes a small layer can form where the temperature increases with height. This layer is called an inversion. This often happens in areas of high pressure, where the air high up often sinks towards the ground.
As it falls, it dries out and warms up. This warm layer of air can act as a lid and trap cooler air near the surface this is because warm air is more buoyant than cold air, and so it will tend to 'float' above the colder air, trapping it.
More importantly, though, areas with heavy pollution are prone to unhealthy air and an increase in smog when an inversion is present because they trap pollutants at ground level instead of circulating them away. Normally, air temperature decreases at a rate of 3. When this normal cycle is present, it is considered an unstable air mass, and air constantly flows between the warm and cool areas.
The air is better able to mix and spread around pollutants. During an inversion episode, temperatures increase with increasing altitude. The warm inversion layer then acts as a cap and stops atmospheric mixing. This is why inversion layers are called stable air masses.
Temperature inversions are a result of other weather conditions in an area. They occur most often when a warm, less dense air mass moves over a dense, cold air mass. This can happen, for example, when the air near the ground rapidly loses its heat on a clear night. The ground becomes cooled quickly while the air above it retains the heat the ground was holding during the day.
Temperature inversions also occur in some coastal areas because upwelling of cold water can decrease surface air temperature and the cold air mass stays under warmer ones. Topography can also play a role in creating a temperature inversion since it can sometimes cause cold air to flow from mountain peaks down into valleys. This cold air then pushes under the warmer air rising from the valley, creating the inversion. In addition, inversions can also form in areas with significant snow cover because the snow at ground level is cold and its white color reflects almost all heat coming in.
Thus, the air above the snow is often warmer because it holds the reflected energy. Some of the most significant consequences of temperature inversions are the extreme weather conditions they can sometimes create.
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