The main factors the affect the weather or climate is temperature, air and rain.

Temperature

Sun is the main source of temperature in nature. We give us light and heat. Weather is much affected by the heat of the sun.

A little portion of the heat of the sun reaches the earth. This temperature heats the surface of the earth.

By the heat of the sun the water of seas, rivers, canals, ponds and wells etc. changes into steam (vapor) and mixes in the air.

`Due to the heat of the sun the changing of water of various sources in steam (vapor), is called evaporation (vaporization)’’.

The water changes in steam due to high temperature quickly and slowly at low temperature.

Effect of sun light and shadow on evaporation

Both the sun –light and shadow leave their effect on evaporation. In the sunlight evaporation occurs quickly, while in shadow it occurs slowly.

Know by experiment

Take water in two jars in equal quantity. Put one jar in sun light and the other in shady place. After five or six hours, see the water level of both jars. You see that water level of the jar putting in sun light subsides more than the jar putting in the shady place.

This experiment shows that sunlight has more heat than shade. So evaporation is faster in heat and show in shade.

On this basis the wet clothes are dried –up soon in summer season, while in rainy season they dry –up late.

Effect of surface on evaporation

The evaporation is faster in large exposed surface and slow in narrow surface.

Know by experiment

Fill water in a wide plate and jar in equal quantity. Now put them in sun light. See the position of water after or six hours.

The water of the plate is dried –up, while some water remains in the jar. This experiment shows that the action of evaporation occurs quickly at wide level, while slowly at narrow level.

On this basis well –spread clothes are dried –up soon than the clothes not spread well.