Page 6 - Curriculum Visions Dynamic Book. To close the book, close the tab.

Anticyclone
Anticyclone
Part of the lower atmosphere
in which the air is sinking and flowing outwards in a broad,
gentle spiral. These winds move clockwise in the Northern Hemisphere and counter-clockwise in the Southern Hemisphere. Because anticyclones are regions of high pressure air, they are often called highs. Anticyclones often signal settled weather.
Because an anticyclone contains sinking air, thick stratus clouds
or deep cumulus clouds do not occur. In summer the sky in an anticyclone may be clear, and
this lets daytime temperatures rise. Ground heating may cause convection, but the sinking air prevents anything larger than tiny (fair weather) cumulus clouds from forming. If the air is moist, the
weather can be dry yet overcast. In winter anticyclones allow air to lose heat to space. This can let frost and fog form. If the
air cools enough, a thin blanket
of cloud may also develop. This kind of cold, dull, windless and monotonous weather is sometimes called ‘anticyclonic gloom’.
In the mid-latitudes some places have anticyclonic weather much
of the time. Places where this happens lie around the subtropics and include the Azores–Bermuda high. Polewards of these semi- permanent highs, anticyclones are formed by the way the air flows. These anticyclones (sometimes called ridges of high pressure) travel around the Earth with depressions, giving affected regions spells of settled weather between periods of depression rain.
 Anticyclone – A barometer shows an anticyclone when the needle points to ‘Fair’ or ‘Very Dry’.
 Anticyclone – Anticyclones are regions marked HIGH on weather maps. They are areas of outward-spiralling and sinking air.
Winds Depression
LOW HIGH
HIGH
LOW
HIGH
HIGH
6