General Circulation and Global Winds

These flashcards cover key vocabulary and concepts related to general circulation and global winds based on the provided lecture notes.

General Circulation

The average air flow around the world, driven by unequal heating of the earth’s surface.

Single-Cell Model

A simplified model of general circulation where the earth is not rotating and has a uniform surface.

Three-Cell Model

A circulation model that divides airflow into the Hadley, Ferrel, and Polar cells due to the rotation of the Earth.

Hadley Cell

The cell extending from the equator to the subtropics, characterized by rising warm air and trade winds.

Ferrel Cell

The cell extending over the mid-latitudes, characterized by the reverse flow of air between the Hadley and Polar cells.

Polar Cell

The circulation cell that extends over the poles, characterized by cold descending air.

Doldrums

A region over equatorial waters where air is warm, pressure gradients are weak, and winds are light.

Subtropical Highs

High-pressure regions located around 30° latitude due to the convergence of air aloft.

ITCZ (Intertropical Convergence Zone)

The region near the equator where trade winds from the Northern and Southern Hemispheres come together.

Westerlies

Winds blowing from the west in mid-latitudes, deflected by the Coriolis force.

Polar Easterlies

Cold winds that flow from the east near the poles.

Weather Systems

The patterns of atmospheric pressure and winds experienced at any given time influencing daily weather.

Hydrology Formula

Water Balance equation: Precipitation (Precip) = Evaporation (Evap) + Runoff.

Temperature Inversion

A situation where air temperature increases with altitude instead of decreases, often leading to stable air.

Subsidence Inversion

A layer of descending air that creates warmer conditions aloft than at the surface, often leading to dry weather.

Sea Level Pressure

The atmospheric pressure at sea level, which influences wind flow patterns.

Jet Stream

A high-altitude, narrow current of strong winds blowing from west to east.

Rossby Waves

Large-scale meanders in high-altitude winds caused by the rotation of the Earth.

Sinking Air

Air that descends in high-pressure areas, contributing to aridity.

Convergence and Uplifting

Processes where air masses meet and rise, often resulting in precipitation.

Climate Zones

Regions of the Earth defined by similar climate characteristics, often related to atmospheric circulation.

Seasonal Shifts

Changes in the position of the ITCZ due to seasonal movements of the sun affecting global weather patterns.

Mediterranean Climate

A climate characterized by dry summers and wet winters, found at mid-latitudes.

Warm Currents

Ocean currents that are usually warm, influencing coastal climates and weather patterns.

Cool Currents

Ocean currents that are usually cold, which can help moderate coastal temperatures.

Topography Influence

The effects that geographical features (mountains, valleys) have on wind and weather patterns.

Semipermanent Highs and Lows

Pressure systems that maintain their position for a significant period, influencing regional weather patterns.