Answer to Question 1
ANSWER: On a typical day, the atmosphere is usually most stable in the early morning around sunrise, when the lowest surface air temperature is recorded. Hence, daytime heating makes the atmosphere more unstable.
Answer to Question 2
ANSWER: An inversion represents an atmospheric condition where the air becomes warmer with height. Inversions that form as air slowly sinks over a large area are called subsidence inversions. They sometimes occur at the surface, but more frequently, they are observed aloft and are often associated with large high-pressure areas because of the sinking air motions associated with these systems.
An inversion represents an atmosphere that is absolutely stable. The reason for this is that within the inversion, warm air overlies cold air, and, if air rises into the inversion, it is becoming colder, while the air around it is getting warmer. Obviously, the colder air would tend to sink. Inversions, therefore, act as lids on vertical air motion. When an inversion exists near the ground, stratus clouds, fog, haze, and pollutants are all kept close to the surface.
Atmospheric pressure decreases as altitude increases.
The Sun by the Atmospheric Imaging Assembly of NASA's Solar Dynamics Observatory
Heating the Atmosphere
Factors That Affect Your Basal Metabolic Rate
Figure and Ground
A 500-kg cannon fires a 4.0-kg projectile with a velocity of 500 m/s relative to the ground. ...