Why temp is low at 25000 ft And high at ground?

Answer 1

The temperature is lower at higher altitudes, such as 25,000 feet, compared to at ground level due to a few key reasons:

Decrease in Air Pressure: As altitude increases, air pressure decreases. Lower pressure means that the air is less dense and has fewer air molecules to absorb and retain heat.

Adiabatic Cooling: As air rises, it expands due to the decreasing atmospheric pressure. This expansion causes the air to cool, a process known as adiabatic cooling. This is why temperatures drop as altitude increases.

Radiation and Heat Retention: The Earth's surface absorbs solar radiation and then re-radiates it as heat. At higher altitudes, there's less atmosphere to trap and retain this heat, so the air is cooler compared to at the ground level where heat is more effectively retained.

Temperature Inversion: In some cases, temperature inversion can occur where warmer air is trapped above cooler air. However, generally, temperatures decrease with altitude in the troposphere, the layer of the atmosphere closest to Earth where weather occurs.

So, the combination of lower air pressure, adiabatic cooling, and the reduced heat retention at higher altitudes results in cooler temperatures as you go higher.