Vertical Atmospheric Pressure Scale Length
The scale length of atmospheric pressure variations in the vertical direction refers to the approximate vertical distance over which the pressure decreases by a factor of $e$ (Euler's number, approximately 2.718). This concept is crucial for understanding how pressure changes with altitude in the Earth's atmosphere.
In the lower atmosphere (troposphere), air density and pressure decrease significantly with height. The characteristic vertical distance over which this pressure change occurs is known as the scale height or scale length.
Determining the Scale Length
Based on standard atmospheric models and observations:
- The pressure variation scale length is primarily determined by temperature and gravity.
- For the Earth's troposphere, this value is typically estimated to be around 7 km.
- This means that for every 7 km increase in altitude, the atmospheric pressure drops by roughly 63% (or decreases to about 37% of its value at the lower altitude).
Therefore, the scale length of pressure variations in the atmosphere in the vertical direction is about 7 km.
Important Questions from Atmosphere
- What is atmospheric window?
- Which one of the following gas was not released through volcanoes around 4 billion years ago?
Absolute humidity in atmosphere at $ 10^\circ $ is $5.0$ g/m$^3$ and maximum amount of water air can hold at same temperature is $ 10$ g m$^3$. What will be the relative humidity at the same temperature?
- The change of atmospheric air temperature with altitude is _____
- Assertion (A) : Warmth of sun’s rays is advantageous during evening time.
Reason (R) : Evening air contains moisture which absorbs the heat and allows the light.
Select the most appropriate option :
