What is one expected effect of climate change on Hadley circulation according to the material?

• A. Hadley cells shrink and retreat toward the equator.
• B. Hadley cells expand poleward with shifts in jet streams and more extreme regional weather.
• C. Hadley cells become nonexistent.
• D. Hadley cells intensify but stay in the same location.

Answer: (B)

How climate change alters the Hadley circulation: warming tends to broaden the tropical overturning, so the rising branch near the equator, along with the sinking zones in the subtropics, expands toward higher latitudes. This expansion is linked to shifts in the mid-latitude jet streams, which tend to move poleward as the climate warms. The result is a reorganized pattern of rainfall and storm tracks, producing more extreme regional weather at the edges of the expanded cells. So the best description is that Hadley cells expand poleward with shifts in jet streams and more extreme regional weather. The other options don’t fit because the circulation is not expected to shrink toward the equator, disappear, or intensify without changing location.