Pressure Systems Flashcards
Anti Cyclone Key Facts
- Right in north hemisphere (clockwise
- Left in south hemisphere (anti-clockwise)
Convergence at high alt/subsidence due to compression.cooling/sinking/diverges at surface
No clouds formation - dry air no condensation
High diurnal variation think deserts
Siberian High - Jan
Canadian High - Jan
Subtropic high pressure belt
Azore High - July
Pacific High - July
Cyclone Key Facts
Move anticlockwise in North
Move clockwise in South
Air rises via convection
Adiabatic cooling condensation = cloud and rain
Diverges at tropopause
(Small Scale Heats lows)
(Large scale heat low - polar front/mid lat depressions)
ITCZ
Upper Low
High/Low if cold air at surface will cause a reduction in upper pressure condition (caved in)
Upper High
Warm air at surface in low or high pressure will give high pressure above (buldge)
Blocking High
High pressure blocking lows
Common around polar front depressions as a result of a sub tropical high moving north block to west to east movement of low pressure systems
Temporary cold/anticyclone
Occurs between two polar front depressions
Heat Depression
Summer time/intense heating/convection
CB Clouds
Hadley Cell
Located at equatorial region
Low pressure at ITCZ caused by insulation over land (advection and then divergence outwards)
Ferrel cell
Mid Lats 30/40
High Pressure in sub tropical regions
Polar Cells
High pressure at poles due to albedo and lack of surface heating area is cold
Global Pressure System in January
Siberian High
Canadian High
Greenland High
Subtropical High
North Australian Low
Low pressure over land mass at equator
Global pressure systems in July
Asian Low
North American Low
Pacific High (Ocean)
Azore High (Ocean)
Subtropical high pressure belt
Omega Block
Extreme version of a high pressure block
Low pressure
Moves inward to a lower pressure + anti clockwise
(Slants across the isobars towards lower pressure)
High pressure
Moves outwards towards lower pressure + clockwise
