Riley lives near a polar zone, where it is cold. He visits his friend Thalia, who lives in a tropical zone, where it is warm all year. They live at similar elevations, and neither lives in a coastal area.What causes the differences in climate where Riley and Thalia live?

Latitude is the key difference: polar zones are at high latitudes, while tropical zones are near the equator at low latitudes. Places near the equator receive more direct sunlight throughout the year, making them warmer. Since Riley and Thalia live at similar elevations and neither lives near a coast, altitude and nearby ocean influences do not explain the difference.

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