Global Wind Patterns and Atmospheric Motion

This set of flashcards covers key vocabulary and concepts related to global wind patterns and atmospheric motion, critical for understanding weather systems.

Microscale winds

Winds characterized by chaotic circulation, lasting from seconds to minutes.

Mesoscale winds

Local winds that last from minutes to hours, affecting areas less than 100 km across.

Macroscale winds

The largest wind patterns that can remain unchanged for weeks and extend around the globe.

Hadley cell

A global circulation pattern characterized by rising air at the equator and descending air at subtropical latitudes.

Polar high

High pressure areas found at the poles, where polar easterlies originate.

Equatorial low

A low-pressure zone at the equator, also known as the Inter-Tropical Convergence Zone (ITCZ).

Westerlies

Winds that blow from the west in the mid-latitudes, part of the macroscale wind systems.

Trade winds

Prevailing winds that blow from east to west in the tropics, found in both hemispheres.

Chinook winds

Warm, dry winds descending the leeward side of a mountain, known for rapid temperature increases.

Adiabatic cooling

The process where air cools as it rises due to lower pressure at higher altitudes.

Doldrums

A region of calm winds at the equator, where trade winds meet and often cause stagnant weather.

Valley breeze

A type of mesoscale wind created when warm air rises from mountain slopes during the day.

Mountain breeze

A type of mesoscale wind created when cool air sinks from mountain slopes at night.

Rossby waves

Waves in the westerlies that impact weather patterns and encircle the globe.

Jet streams

Fast, high-altitude wind currents that influence weather patterns and aircraft operations.

Ferrier cell

A cell in the three-cell model of atmospheric circulation found between the Hadley and polar cells.

Polar easterlies

Cold winds that blow from the east at the polar regions.

Subtropical high

Areas of high pressure located around 20-35° latitude, often characterized by calm weather.

Cyclones

Large scale atmospheric systems characterized by a low pressure center and rotating winds.

Anticyclones

High pressure systems with descending air and typically clear skies.

Inter-Tropical Convergence Zone (ITCZ)

A region near the equator where trade winds converge, leading to a low pressure zone and precipitation.

Monsoon

A seasonal wind change that brings drastic shifts in precipitation, commonly affecting South Asia.

Surface winds

Winds blowing at the Earth's surface, influenced by pressure differences.

High pressure system

An area of high atmospheric pressure often leading to calm and clear weather.

Low pressure system

An area of low atmospheric pressure associated with rising air, clouds, and precipitation.

Idealized circulation model

A theoretical model of atmospheric circulation, ignoring land-sea contrasts and other complexities.

Three-cell model

A more complex model of global circulation that considers Earth's rotation and divides the atmosphere into three cells.

Temperature gradient

The difference in temperature over a certain distance that drives wind and weather patterns.

Jet stream patterns

Configurations of jet streams which can significantly influence weather events and temperatures.

Temperature inversion

A scenario where air temperature increases with altitude, which can trap pollutants and affect weather.

Wind shear

A difference in wind speed or direction between two points in the atmosphere, often strong in jet streams.

Coriolis effect

The deflection of moving objects, such as air, caused by the Earth's rotation, influencing wind direction.

Surface pressure maps

Charts depicting atmospheric pressure at the Earth’s surface, used to analyze weather systems.

Land-sea breezes

Winds created due to temperature differences between land and water surfaces.