EVERYDAY SCIENCE

Detailed explanation-1: -Clouds form when air is cooled to temperatures at which some of the contained water vapor condenses to liquid or ice. This happens because temperature drops are accompanied by reduction in the capacity of a volume to hold water vapor.

Detailed explanation-2: -As air rises drier air is added (entrained) into the rising parcel so both condensation and evaporation are continually occurring. So, cloud droplets are constantly forming and dissipating. Therefore, clouds form and grow when there is more condensation on nuclei than evaporation from nuclei.

Detailed explanation-3: -Some clouds form as air warms up near the Earth’s surface and rises. Heated by sunshine, the ground heats the air just above it. That warmed air starts to rise because, when warm, it is lighter and less dense than the air around it. As it rises, its pressure and temperature drop causing water vapor to condense.

Detailed explanation-4: -Clouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. For this to happen, the parcel of air must be saturated, i.e. unable to hold all the water it contains in vapor form, so it starts to condense into a liquid or solid form.

Detailed explanation-5: -The two main large scale lifting processes that result in cloud formation are convection and advection of air. Convection refers to air rising vertically in the atmosphere due to heating. Advection is the horizontal transfer of air that usually results in warmer air being forced up over cooler air.