Rain

Question 1

Explain conventional rain

Answer 1

1. The suns energy heats up the ground
2. The air in contact with the word ground is heated by conduction
3. The heated air expands and becomes lighter tan the air around it
4. This unstable heated air which holds a lot more moisture rises
5. As warm air rises it cools until dew point temp is reached when water vapour condenses to form clouds
6. In the upper draft of rising air water vapour continues to condense into water droplet around the cool surfaces of suspended ice crystals, dust and other impurities to form towering cumulonimbus clouds
7. Tiny water droplets in the clouds coalesce to form bigger water droplets
8. When the water droplets become too heavy to be suspended, conventional rain falls (accompanied with lightning and thunder)

Question 2

What is relief rain?

Answer 2

Relief rain means rain caused by land varying in height. Relief rain is formed when air cools as it rises over relief features in the landscape such as hills or mountains.

Question 3

Explain how relief rain occurs

Answer 3

Prevailing winds pick up moisture and push the moist air up the windward side of a mountain. The rising air cools and condenses on condensation nuclei at dew point temperature and clouds are formed. Water droplets in the clouds collide and coalesce and when they beacons large and heavy enough they fall to the ground as rain on the windward side.

Question 4

How are clouds formed?

Answer 4

As air rises up in the atmosphere, it cools reducing the amount of water vapour it can hold. Eventually the water vapour in the air exceeds the maximum amount if water vapour the air can hold. At thsi temperature, air condense into water droplets n condensation nuclei which provide surfaces for water vapour to change into water droplets or solid ice particles.