How are clouds formed what they cause the rainfall
Answers
Clouds
As an air parcel rises it cools, the water vapour condensing when it reaches the dew point. Sunlight is scattered from the resultant droplets so that the emergent clouds can be seen by human eyes by their white, diffuse light. The best example of this is when air parcels rise from the warm ground in summer; those with only a small buoyancy compared to the surrounding atmosphere produce ‘fine weather’ clouds, those with stronger buoyancy climb higher and form thick clouds and heavy rainfall.
In low pressure systems with their cyclonic (anti-clockwise, in the northern hemisphere) air flow, warm, humid, subtropical air is transported to the north-east. Due to its lower density it moves up over the colder northern air, cooling as it rises. This is how clouds form on the warm fronts of such pressure systems in the mid-latitudes. Conversely, on the western side of the low the cold air moves southward, pushing under the warmer subtropical air and raising it up above its condensation level to form clouds on the cold front. Clouds can also be formed from the cooling and condensation that occurs when air flows over physical obstructions like mountain ranges
Precipitation
Cloud droplets are tiny, only 1/100 mm in diameter, and are thus very light and practically float freely in the air. As the droplets collide, with time some grow larger than others and start to slowly fall, falling faster as they accumulate more and more droplets. If the cloud of droplets is dense enough to form droplets greater than 1/10 mm in diameter through this process, the droplets survive the fall through the air below the cloud, despite evaporation, and reach the ground as rain. This process develops what is known as ‘warm rain’, but in our part of the world it is responsible for only the weakest drizzle from near surface clouds. In the warm tropics it is responsible for intense rainfall from clouds lower than 5 km.
More important in the formation of heavier rain is a process that involves frozen particles. Although the temperature at cloud level is often below 0 ºC, the droplets themselves remain in liquid form – this is known as ‘super cooling’. In these circumstances, a tiny disturbance (a collision, or the presence of a suitable ice nuclei) is enough to cause the droplets to suddenly freeze solid. Water vapour condenses more easily onto ice particles than onto liquid water droplets, so these ice particles grow faster than the surrounding droplets and begin to fall sooner. They grow further through the accumulation of other droplets and quickly become large enough to reach ground level. Since the ice particles encounter ever warmer layers of the atmosphere as they fall, they often melt as they fall and reach the ground as rain. If they have formed in a very thick cloud however they can become so large that they do not melt before they reach the ground and fall as granulated ice particles. Storm clouds can contain upward winds that are so strong that ice particles that have already melted at the surface are pulled back up into the cloud and freeze anew. At some point they will fall again, growing by the accumulation of other droplets and melting again. Occasionally this process is repeated a number of times, leading to the eventual formation of large, layered hailstones
Hey mate.here is your answer.
Firstly we should know what is a cloud.
CLOUD-A cloud is a large collection of tiny droplets of water .The droplets are very small.
Now the questions arises.How are clouds formed??
Clouds are formed when warm and moist air rises up, cools and then expands in the atmosphere. what
How do the clouds cause rainfall??
When water molecules warm up, they change from a liquid into a gas and rise up into the air.When clouds get so full of water droplets that they can't hold any more, the water falls back to the ground as rain!
hope it helps u.plz mark as brainliest .
Alice