Clouds Formation and Types of Clouds


This article will clearly explain about Clouds and Classification of clouds.


  • Clouds/clouds are defined as aggregates of several tiny water droplets, ice particles or a mixture of both in the air generally much above the ground surface.
  • Not all clouds produce precipitation, but precipitation will not occur without the formation of a cloud first.
  • Clouds are important factors in the heat energy budget.
  • They absorb some of the incoming solar energy, reflect some of that energy back to space and scatter or diffuse other wavelengths of energy to and away from Earth.
  • Clouds form when air happens to cool, to dew point and vapour condenses in Water droplet and or ice crystals.
  • Two conditions are necessary for cloud formation.They are
  1. Air must be Saturated. (When air of given temperature holds all of the Water Vapour that it possibly can it is said to be in a state of saturation).
  2. There must be a substantial quantity of small particles called Condensation nuclei, around which liquid droplets/ ice crystals are formed when vapour condenses.
  • Cloud indicates the state of Atmosphere and whisper hints about the future weather.


  • The general classification of clouds was proposed by Luke Howard in 1803.
  • Howard’s Classification was a descriptive one and based on the shape of height.Types of clouds



Howard recognised three standard shapes of clouds and used three Latin words for the same.

(1) Cirrus Clouds – Like a lock of curly hair.

  • Cirrus clouds form at very high altitudes, normally 6000-10,000 m, and are made up of ice crystals.

(2) Stratus Clouds – Like a sheet/layer/ceiling of a room.

  • Stratus clouds appear at lower altitudes from the surface up to almost 6000 m.
  • The basic characteristic of stratus clouds is their horizontal appearance, in layers of fairly uniform thickness.

(3) Cumulus Clouds – Like a heap/pile.

  • Cumulus clouds develop vertically rather than forming the more horizontal structures of the cirrus and stratus types.
  • Cumulus clouds provide visible evidence of an unstable atmosphere.
  • He also used the word Nimbus to denote a rain bearing cloud.



There are three subtypes.

1) High clouds(Cirro): Clouds formed at an elevation above 20000 feet(7000 meters).

2) Low Clouds(Strato): Clouds formed at an elevation below 2000 meters (7000 feet).

3) Middle Clouds(Alto): The ones which are formed at elevations between 2000 – 7000 meters. I.e between 7000-2000 feet.


  • Such clouds grow from low bases to a height of as much as 15 km (above 50,000 ft).
  • Such clouds usually have limited horizontal spread (As they are related to localised heating (or) convection).


  • High clouds are mainly cirrus in shape.
  • Low clouds are mainly stratus in shape.
  • Clouds which are vertically developed are mainly cumulus in shape.
  • Howard used the word Alto as the prefix to denote a middle-level cloud.
  • High clouds are composed largely of Ice crystals.
  • Supercooled droplets refer to the microscopic droplets of water at the temperature below 0 degrees C.
  • Middle-level clouds are hugely formed of water droplets which frequently exists in a supercooled State at the temperature well below freezing.
  • Howard also made composite names using the above-mentioned Latin words such as Cumulonimbus Nimbus and cirrostratus.

Plains and Types of Plains

Plains and Types of Plains

This article will clearly explains about Plains and Different types of plains


  • Plain is extensive, relatively level area of land. It exhibits gentle slopes and small local relief.
  • It occupies slightly more than one-third of the land surface. Plains are found on all continents except Antarctica. Some are tree-covered and others are grassy.
  • They have different names in different climates and countries. E.g. steppes, prairies, pampas, veld etc.
  • The cause of the formation of plains included the erosive action of water, glaciation, the draining of a lake, deposition of sediments and the upliftment of a Continental shelf.

Types of Plains

On the basis of their mode of formation, the plains can be of various types.

  1. Structural Plains
  2. Erosional Plains
  3. Depositional Plains

Structural Plains

They are structurally depressed areas, which are largely formed by horizontally bedded rocks relatively undisturbed by crustal movements. E.g. Great plains of the USA, Central lowlands of Australia.

Erosional Plains

They are formed by the action of various Erosional events that work to bring an elevated, region near to the sea level.

  1. Riverine Erosion Plains
  2. Glaciated Plains
  3. Wind Eroded Plains

Riverine Erosion Plains

Riverine Erosion Plains will form peneplains, which are characterised by residual hills known as Monadnocks.

Glaciated Plains

Glaciated Plains forms ice-scoured plain, e.g. ice scoured plains of North-Western Europe and North America.

The Wind Eroded Plains

In arid and semi-arid regions, wind deflation will blow desert materials, lowering the level of land and forming extensive plains, e.g. the Reg of Africa.

Depositional Plains

The plains formed by the filling up of sediments carried by agents of Erosion like wind, rivers, glaciers and underground water into depressions are called Depositional plains.

  1. Riverine Alluvial plains
  2. Glacial Plains
  3. Loess Plains
  4. Lacustrine Plains

Riverine Alluvial Plains

These plains are formed by the deposition of sediments brought down by rivers. It includes Piedmont Alluvial plains, floodplains and delta plains.

Glacial Plains

Glacial Plains are formed by the deposition of unsorted sands and travels brought down by glaciers. Glacial Plains are divided into three types on the basis of composition and structure. Till plains, Morainic plains and Outwash plains.

Loess Plains

Loess Plains are formed due to the deposition of sand and clay brought by the winds. These plains lack in layers but are highly porous. The soil of these plains is very fertile e.g. the Great plain of Northern China.

Lacustrine Plains

Lacustrine Plains are the plains formed by lakes filled by the sediments brought down by the rivers. The valley of Kashmir is an example of this type.

The difference between Structural, Erosional and Depositional Plains

Structural Plains

Structural Plains formed due to the uplift of a part of the sea floor e.g. the Great plain of USA.

Erosional Plains

Erosional Plain formed when the elevated tract of land is worn down by the process of Erosion.

E.g. plain of North Canada.

Depositional Plains

Depositional Plain formed by filling up of sediments into depressions along the foothills, lakes and seas e.g. Info Ganga plain.