Temperature Inversions

Question 1

Temperature Inversion

Answer 1

Occurs when the air mass at high altitudes is warmer than the air mass at lower altitudes.
Normally the temperature decreases by the estimated lapse rate as altitude increases but in a temperature inversion, this is not the case.
During a temperature inversion, a pilot should expect an increase in temperature as the altitude increases.

Question 2

What are temperature inversions caused by?

Answer 2

Rapid radiation cooling of the surface and air near the surface.
On cold, clear nights with a stable air mass that has little wind and clouds, the earth radiates heat quickly into the atmosphere. With no clouds to hold that heat close to the surface, and no wind to move it horizontally, the warm air rises.
Other causes could be ahead of a warm front

Question 3

Temperature inversions are associated with…

Answer 3

Stable air, as they are essentially a gaseous cap to vertical development that are associated with a stable layer of air below the warm air cap.

Question 4

Visibility during a temperature inversion can be…..

Answer 4

Decreased, because the rising air that usually recycles clean air to the surface is not present. Particles such as smoke, dust, haze, fog, etc. will be trapped near the surface below the warmer layer of air below it.

Question 5

When the relative humidity is high and there is a temperature inversion, a pilot should expect…

Answer 5

Conditions of smooth air above the inversion layer, and poor visibility, fog, haze, or low clouds below the inversion layer.

Question 6

The layer of air at the middle of a temperature inversion where you have warm air sandwiched between colder air below and above….

Answer 6

Can have considerable turbulence and wind shear due to the mixing of cold and warm air.

Question 7

The presence of ice pellets on the surface is evidence of…

Answer 7

A temperature inversion with freezing rain at higher altitudes falling to the surface and freezing into ice pellets.
It is likely that the precipitation starts as ice or snow high in the cold layer of air in the upper atmosphere, slightly melts as it goes through the warm layer of air in the temperature inversion, before again entering the lowest layer of cold air near the surface where it freezes again into ice pellets.