Anticyclones Flashcards
Mid latitude continents: winter
Land chills quickly, leads to high pressure.
Mid latitude continents: summer
Land heats up quickly, leads to a fall in pressure.
Continental anticyclones: (5)
Sinking motion, very cold air at surface. Little cloud. Air is dry; far from moisture. Seasonal; winter. Occur still higher latitudes.
Continental anticyclones: Autumn (2)
Vertical rate of pressure change is rapid because the lowest 2km of the troposphere is so cold.
Intense cooling begins; increase in air density; start of shallow anticyclone.
Continental anticyclones: Winter
Strong radiative cooling to space.
Subtropical anticyclones: seasonal variation
Winter - tend to be at lower latitudes than in summer.
Summer - higher latitudes; more intense.
Subtropical anticyclones: occur at around
30’ N/S
Subtropical anticyclones: air is sinking from
Upper to lower levels; subsidence.
Air spirals out into lower levels.
Subtropical anticyclones: lowest 1 km of atmosphere
Over the oceans is rich in moisture.
Subtropical anticyclones: weather conditions (3)
Dry weather.
Low relative humidity.
Cloudy - shallow stratiform cloud.
Subtropical anticyclones: semi permanent high over
Subtropical pacific and N Atlantic Ocean (Azores high) w
Subtropical anticyclones: source regions for air masses; (2)
Deep subsiding motion.
Dry air is sinking into higher pressure, warming at the DALR of 9.8 ‘C km-1
Subtropical anticyclones: Dry air sinks, warming adiabatically; (3)
Relative humidity decreases simultaneously.
Dry bulb temperature increases rapidly.
Absolute humidity remains the same, but saturation value increases as DB temp rises.