With what type of weather is rising air associated?
2 Answers
Low pressure system
Explanation:
The reason is that as the air rises it is having a lesser load on the ground, seeing as air pressure is simply the column of air directly above you. So that rising air gives rise to a low pressure system.
This type of system typically creates clouds which can eventually cause rain. Winds are also produced as air travels from areas of high to low pressure. Rule of thumb, if you're looking up at the sky and see clouds, you are likely under a low pressure system.
Days where you see not a cloud in the sky is when you are under a high pressure system experience sinking air.
It is very dependent on what the factor that is causing the air to rise.
Explanation:
Air rises due to 5 reasons, none of which really involve the air above it and most do not involve a low pressure system.
The first reason is Convection, or the uneven heating of the Earth's surface. This creates areas of warmer air that have a much higher volume. Higher volume lowers pressure.
The second reason is low level Convergence. This is the trend of air moving from areas of high pressure to low pressure. As a result the incoming air has to move somewhere so it moves up. This is your low pressure system.
Thirdly, mechanical turbulence is the mixing of air in the boundary layer (first 3000ft or so) of the atmosphere. This mixing cause the air to lift.
Up-slope flow or orographic lift is the lifting of air by a change in terrain. Air blowing up the side of a mountain for example.
Finally there is the action of fronts. This is where moving cold air (dense) pushes warmer air (less dense) causing it to rise.
In all cases the rising air will create cloud, as the temperature of the rising air will drop and the relative humidity will increase. Wind is an issue of pressure gradient and therefore will be a factor in come cases and in the case of mechanical turbulence wind is what causes the air to rise.
The instability of the air mass is really what will determine what weather you are going to get. The more unstable the air mass the more cloud you get. The more cloud you get the greater the change of precipitation. A very unstable air mass will give you much more developed clouds that will eventually lead to thunderstorms and other violent such weather. Stable air that rises will usually give you layered cloud (fog in the case of orographic lift), but the air will drop again as soon as the lifting element allows it too.
