GS Question

The major hot deserts in the northern hemisphere are indeed located between 20-30 degrees of latitude and on the western side of the continents. There are a few factors that contribute to this particular distribution pattern:

1. Subtropical High Pressure Zones: Between 20-30 degrees latitude, there are regions known as subtropical high-pressure zones. These zones are characterized by descending dry air, which inhibits the formation of clouds and precipitation. These high-pressure zones result in arid conditions, creating deserts.

2. Global Wind Patterns: The global wind patterns, known as the Hadley Cells, play a crucial role in the formation and distribution of deserts. Warm air rises near the equator, creating a low-pressure zone. As this air moves towards the poles at higher altitudes, it cools and descends at around 20-30 degrees latitude. As the air descends, it warms up, leading to dry and arid conditions conducive to desert formation.

3. Rain Shadow Effect: The western sides of the continents where the major hot deserts are located often experience a rain shadow effect. When moist air approaches a mountain range, it is forced to rise, cool, and condense, leading to precipitation on the windward side of the mountains. As the air moves over the mountains and descends on the leeward side, it becomes drier. This process creates a rain shadow, where the leeward side experiences much less rainfall, resulting in arid conditions and desert formation.

In summary, the combination of subtropical high-pressure zones, global wind patterns, and the rain shadow effect contributes to the dominant presence of hot deserts between 20-30 degrees North latitude and on the western side of the continents in the northern hemisphere.