What is the effect of the Coriolis force on wind circulation around low and high pressure systems?

• A. The Coriolis force deflects moving air to the right in the Northern Hemisphere and to the left in the Southern Hemisphere; around lows, winds converge and rotate counterclockwise in NH and clockwise in SH; around highs, winds diverge and rotate clockwise in NH and counterclockwise in SH.
• B. The Coriolis force deflects moving air toward the equator in both hemispheres.
• C. The Coriolis force has no effect on wind circulation patterns.
• D. The Coriolis force only affects ocean currents, not winds.

Answer: (A)

The Coriolis force deflects moving air to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This deflection shapes how winds circulate around pressure systems. Near a low-pressure center, air moves toward the center at the surface (converges). As that air spirals inward, the Coriolis deflection causes the flow to rotate counterclockwise around the low in the Northern Hemisphere and clockwise around the low in the Southern Hemisphere. Near a high-pressure center, air moves outward from the center (diverges). With the Coriolis deflection, the surface flow around a high rotates clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere. This combination of inward/outward flow with hemisphere-dependent deflection explains the distinct wind patterns around lows and highs.