Upload
anjalif
View
313
Download
1
Tags:
Embed Size (px)
Citation preview
How are clouds formed?
All air contains water, but near the ground it is usually in the form of an invisible gas called water vapor.
When warm air rises, it expands and cools. Cool air can't hold as much water vapor as warm air, so some of the vapor condenses onto tiny pieces of dust that are floating in the air and forms a tiny droplet around each dust particle.
When billions of these droplets come together they become a visible cloud.
Cumulus clouds
Cumulus means “heap” or “pile” in Latin.These clouds are white, puffy clouds that look like pieces of floating cotton. Cumulus clouds are often called "fair-weather clouds". Colour: White/ GreyishShape: Cauliflower like Height: Medium
Nimbus clouds
Nimbus means “cloud” or “rain storm” in Latin.These are rain clouds.They resemble the cumulus clouds but are dark and dense. Colour: Dark grey / blackShape: Rounded tops and flat baseHeight : Low
Cirrus clouds
Cirrus means “ringlet” or “curl of hair” in Latin.These are like fine thin strands.They predict fair to pleasant weather. Colour: WhiteShape: FeatheryHeight: High
Stratus clouds
Stratus means “spread out” in Latin.These are flat, hazy sheets of clouds.They are found in layers and are know as fog if found very low.Colour: White / GreyishShape: Thin sheet likeHeight: Medium / low
How does it rains ?
When there is continuous condensation of water vapour in the air, it results in the formation of minute droplets of water.
When these droplets of water join together, they form bigger drops, which become too heavy to float in clouds and begin to fall.
This falling of condensed water is called rainfall or precipitation.
Relief rainfall
1. Warm moist air from the sea.
2. Forced to rise over the hills.
3. Air cools as it is forced to rise.
4. Condensation occurs.
5. Clouds form.
6. Results in rain.
7. Occurs in the state of Maharashtra and Meghalaya.
Conventional rainfall
1. The sun heats the ground which heats the air.
2. Warm air rises.
3. Air cools as it is forced to rise.
4. Condensation occurs.
5. Clouds form.
6. Results in rain.
7. Occurs in the states of West Bengal, Orrisa and Tamil Nadu.
1. Mass of warm air meets a mass of colder air.
2. Lighter warm air rises over heavier cold air.
3. Warm air cools.
4. Condensation occurs.
5. Clouds form.
6. Results in rain.
7. Occurs in the states of Himachal Pradesh and Punjab.
Frontal rainfall