Calculate surface pressure: p = F/A The force that we just received as a result from the calculation above is distributed over the bearing surface. So, we just need to divide the force by the calculated area to get the surface pressure.

Air molecules in the parcel (or the balloon) have to use their kinetic energy to expand the parcel/balloon kinetic energy to expand the parcel/balloon. The lost energy is used to increase the potential energy of air molecular.

A parcel has an original temperature and dewpoint that it obtains as it breaks away from the surface and rises. As long as the parcel remains less dense than the surrounding environmental air then it will continue to rise. A parcel is less dense by being warmer than the surrounding environmental air.

A rising parcel of air expands because the air pressure falls with elevation. This expansion causes the air to cool.

It is common knowledge that warm air rises. Warm air rises primarily due its lower density as compared to cooler air. As the temperature increases, the density of the air decreases. But even air that is of a lower density will not begin to rise by itself.

Air that has a tendency to sink is known as a stable air. If the air parcel’s temperature is greater than the temperature of the surrounding air mass, the air parcel is less dense and tends to rise. Rising air, as we have already learned, is known as unstable.

The atmosphere is said to be unstable when a lifted parcel reaches a region where it accelerates upward because it has become less dense than the surrounding atmosphere, i.e., push a parcel up and it shoots upward on its own.

Moisture – There must be sufficient water vapor in the air to build a cloud. Cooling air – The air temperature must decrease enough for water vapor to condense.

The requirements for sufficient water vapor and CCN are rarely the limiting factors for cloud development. Typically, the limiting factor is a cooling mechanism. Thus, the air temperature needs to be lowered to the dewpoint temperature for a cloud to form. If a cooling mechanism is not present, clouds will not form.

Conditions necessary for clouds to form. Clouds form when the air is cool and condensation occurs. For water vapor to condense and to form a cloud, a solid surface must be available, like DUST.

– Most clouds form when air cools to the dew point as a parcel of air rises vertically. – There are four lifting mechanisms that form clouds: Orographic Lifting, Convection, Convergence, and Updraft.