Question

Give reasons for the following.

The Thar desert region experiences low pressure during the month of May.

Answer 1

1. Intense Solar Heating: In May, the Sun advances northward to the Tropic of Cancer, beaming virtually directly across northern and western India. The sandy soil of the Thar Desert absorbs heat quickly, causing midday temperatures to spike, frequently topping 45°C to 48°C.
2. Rapid Expansion of Air: According to physical law, when the air right above the desert floor is strongly heated, it expands, becomes lighter, and rises quickly into the higher atmosphere via powerful convection currents.
3. Creation of a Thermal Low: The rapid upward movement of this heated air leaves behind a vacuum-like deficit of air molecules at the ground surface. This vacuum directly manifests as a deep, localized thermal low-pressure trough, which eventually becomes strong enough to help pull in the main monsoon winds from the oceans in the following months.