An airstream is the name given to a body of air, or air mass, that moves from its source region to another area, moving with it variable weather types according to the source region.
It can also mean the flow of air that is driven backwards by an aircraft propeller, also referred to as a backwash, slipstream or any other uninterrupted stream or discharge of air.
Types of airstream
In climatology, an airstream is a high-altitude airstream blowing from the source (frequently a large body of water or land) near the top of the troposphere and has important effects on the formation of weather fronts.
For the purpose of example, we will use the UK landmass to illustrate airstreams. Thanks to it's location, the UK experiences six different airstreams:
Polar Maritime - This airstream originates in Denmark, bringing cold fronts and occasionally snowy weather.
Arctic Maritime - This airstream develops within the Arctic cirle and surrounding region, and passes south-south-east, bringing very cold fronts.
Polar Continental Maritime - This airstream develops over Scandinavia and Russia, again bringing cold weather Westerly.
Continental Maritime - This airstream originates over Europe, typically blowing milder weather North-Westerly to the UK.
Tropical Maritime - This airstream is the warmest of all the UK experiences, bringing warm pleasant weather North from tropical regions.
Polar return Maritime - This airstream brings mild wet weather from the South-West over the Atlantic ocean, hence frequent rain.
An Air current is wind or air moving, sometimes with considerable force, from an area of high pressure to an area of low pressure.
