What term describes the zones of irregular horizontal surface air circulation near 30 degrees North and 30 degrees South latitudes, where dry air descending from high altitudes can create deserts such as the Sahara?

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Multiple Choice

What term describes the zones of irregular horizontal surface air circulation near 30 degrees North and 30 degrees South latitudes, where dry air descending from high altitudes can create deserts such as the Sahara?

Explanation:
The zones around 30°N and 30°S are subtropical high-pressure areas where air sinks and surface winds are weak. In the global Hadley cell, air rises near the equator, moves poleward at high altitude, then sinks around these subtropical latitudes. When air descends, it heats and dries, leading to clear skies and arid conditions. That combination of calm surface winds and dry descending air is why deserts such as the Sahara form in these belts. The term for these calm, dry latitudes is horse latitudes.

The zones around 30°N and 30°S are subtropical high-pressure areas where air sinks and surface winds are weak. In the global Hadley cell, air rises near the equator, moves poleward at high altitude, then sinks around these subtropical latitudes. When air descends, it heats and dries, leading to clear skies and arid conditions. That combination of calm surface winds and dry descending air is why deserts such as the Sahara form in these belts. The term for these calm, dry latitudes is horse latitudes.

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