Railsback's Fundamentals of Quaternary Science Global climate zones II: an idealized simple view, with weather

Vertical Map view Climate Zones Wind Belts Precipitation cross-section and Zones Polar Cell H Polar High Dry Easterlies 60°N Subpolar Lows Polar Front Rainy Ferrel L L L L Cell Temperate Westerlies

Winter wet; summer dry 30°N H H H H H H Subtropical Highs Horse Latitudes Dry (anticyclones) Hadley Winter dry; summer wet Cell Easterlies Trade Tropics (Northeasterlies) Winds Intertropical L L L L L L L 0° Convergence Doldrums Rainy Zone (ITCZ)

Easterlies Trade Tropics (Southeasterlies) Winds Hadley Cell Winter dry; summer wet H H H H H H 30°S Subtropical Highs Horse Latitudes Dry (anticyclones) Winter wet; summer dry Temperate Westerlies Ferrel Cell L L L L Subpolar Lows Rainy 60°S Polar Front Easterlies Polar Cell H Polar High Dry

Part I of this series showed a schematic pattern of atmos- Earth's easterlies are relatively constant because they are are more variable. The westerlies' changes in flow, as transient pheric circulation on Earth. This page changes that presentation driven by the constant heating (and low pressure) at the highs and lows move through the middle latitudes, give by suggesting some variability of the westerly winds. That vari- equator, and by the constant cold (and high pressure) at the variable weather that characterizes the middle latitudes. ability is shown here as variation through space, but it is also a the poles. The westerly winds, as the Earth-surface variability through time: it is the weather of the westerlies belt. expression of the more secondary or ancillary Ferrel Cells, LBR 2/2013 FQSGlobalClimateZonesII02.odg