Pollution

RAIN

When water bodies are heated during the day time, a large amount of water evaporates and goes into the air.

Some of the water evaporated in the form of water vapour also goes into the atmosphere because of few biological activities.

The hot air rises up because it is lighter, carrying water vapour with it.

As it rises it expands and cools up, causing the vapour in the air to condense.

This condensation is also associated with few particles of dust and suspended particles in the air acting as the nucleus for these water droplets.

Once the water droplets are formed, they grow bigger by the condensation.

When the droplets are grown big and heavy, they fall down in the form of rain.

Sometimes when the temperature is low enough, precipitation may occur in the form of snow, sleet and hail

AIR POLLUTION

Air gets polluted when there is increasing levels of Oxides of Nitrogen and Sulpher.

The quality of air gets affected in the course of time.

The fossil fuels like coal and petroleum contain small amounts of Nitrogen and Sulpher.

When these fuels are burned Nitrogen and Sulpher are too burnt and produce different Oxides of Nitrogen and Supler.

Inhalation of these gases is dangerous, they also dissolve in rain to give rise to acid rain.

The combustion of these fuels may also cause the increase in suspended particles in the air.

These suspended particles cause low visibility during the nigh times.

They also lead to allergies, cancer and heart related problems.

WATER• Water occupies very large area on earth’s

surface and underground.

• Water exists as water vapour in the atmosphere.

• Most of the water is found in seas and oceans in the form of saline.

• Fresh water is found in frozen ice caps at the two poles and on snow covered mountains.

• In summers most places have to face shortage of water.

• And in rural areas where water supply systems have not been installed people are forced to spend considerable amount of time in fetching water from away sources.

• The availability of water decides not only the species which survive on water at particular areas, but also the diversity of life there.

WATER POLLUTION