Discuss the concept of air mass and explain its role in macro-climatic changes.
Answers
Air masses are large bodies of slow moving air extending up to troposphere and cover a large area.
Their characterizes are dependent upon the surface, latitudinal position, size and speed.They acquire a distinct identity by their humidity, orgin and movement.They are classified based on,Latitudinal origination - Arctic, Tropical, Equatorial, Antarctic,etc.
Continental air mass/ Oceanic air mass.
They have huge impact on the macro – climate of region. Air masses cause,
1-Desertification:They cause arid conditions when dry air mass is present in a region. Sahel region of Africa is impacted by this.
2-Precipitation:The Monsoon trough present in North India is an important factor in attracting the south west monsoon winds. The creation of this trough is aided by Tibetan plateau.
3-Frontal Precipitation – when warn air mass and cold air mass come in contact frontal precipitation occurs. It is widely witnessed in temperate region.
4-The Air masses when pass through warm water or currents acquire their moisture and cause rainfall in coastal regions.
Cyclonic and Anticyclone conditions:
5-Air masses also significantly impact them. Cyclonic rainfall is prevalent is Temperate region but not as destructive tropical cyclones.
Thus air masses play a significant role is influencing macro-climate of a region.