You have seen steam issuing from the spout of a tea-kettle or from a steam locomotive. Being lighter than air, steam rises up into the air. When water evaporates, the vapour rises up into the air and cools. Very minute droplets of water or even ice crystals are thus formed around particles of dust and smoke suspended in the upper air. These innumerable tiny droplets remain suspended high up in the air in from of Clouds are of several types. They differ in shape and float at different heights in the atmosphere. The types of clouds are:

Cirrus: The cirrus is very high clouds, above 7,620 meters and look like heaps of white feathers. They are composed of snow and ice crystals. The appearance of a cloud types often indicates a fair weather.

Cumulus: On hot summer days you must have seen heaps of white clouds shaped like cauliflowers floating about in the sky. Such clouds cause short sharp showers often accompanied with lighting and thunder. We call them thunder-clouds also

Stratus: this cloud type is like a dark grey sheet extending over the whole sky. It is low height and brings light rain

Nimbus: these are the real rain clouds. Such Clouds look dark because they are very thick and speed out over a very large area, floating at a low height.

Clouds, however, do not generally occur in pure type. They show mixed characteristics of two types generally. So could are described as cirrus, cirrostratus, cirrocumulus, stratus, altostratus, altocumulus, nimbus, nimbostratus, cumulus, cumulonimbus, etc.

Fog and Mist

Land loses heat by radiation during the night. Naturally, it loses more heat on clear, cloudless night loses its moisture which collects on the objects as droplets. This is dew. Hoar Frost

When the nights are very cold and temperature falls below freezing point, moisture from air collects night. Frost causes much damage to plants. Farmers may sometimes loss the whole crop due to frost.