Which of the following pressure belts of the globe are dynamically formed?

1. Equatorial low-pressure belt

2. Subtropical high-pressure belts

3. Subpolar low-pressure belts

4. Polar high-pressure belts

Correct answer/s:

Why are these "Dynamically Formed"?In climatology, pressure belts are classified based on what creates them: thermal (temperature) or dynamic (movement/rotation of the Earth).Subtropical High-Pressure Belts (Statement 2): These are formed due to the subsidence (sinking) of air. Air that rises at the Equator cools and moves poleward, eventually sinking around $30^\circ$ N and S latitudes due to the Coriolis force and the crowding of air currents. This "piling up" of air creates high pressure.+1Subpolar Low-Pressure Belts (Statement 3): These are formed due to the ascent of air caused by the convergence of contrasting air masses (Warm Subtropical air and Cold Polar air) and the rotation of the Earth, which "throws" the air away from these latitudes (centrifugal action).Understanding the Thermal BeltsThe other two options are Thermally Induced, meaning they are caused strictly by heating and cooling:Equatorial Low-Pressure Belt (Statement 1): Formed because the intense sun at the equator heats the air, causing it to expand, become light, and rise.Polar High-Pressure Belts (Statement 4): Formed because the extreme cold at the poles causes the air to contract, become dense, and sink.