Lapse Rate Calculator

What is the Environmental Lapse Rate?

The Environmental Lapse Rate (ELR) is the rate at which air temperature decreases with an increase in altitude in the atmosphere. It's an important concept in meteorology that helps understand atmospheric stability and weather patterns.

How to Use This Calculator

1. Enter the initial temperature (T₁) in degrees Celsius
2. Enter the final temperature (T₂) in degrees Celsius
3. Enter the initial altitude (Z₁) in meters
4. Enter the final altitude (Z₂) in meters
5. Click the "Calculate" button to compute the environmental lapse rate

Understanding the Results

The calculator displays the lapse rate in °C per 100 meters. Standard atmospheric conditions typically show a lapse rate of about 6.5°C per 100 meters in the troposphere (the lowest layer of the atmosphere).

Interpreting the Lapse Rate

• Positive lapse rate (temperature increases with altitude): This is unusual in the troposphere but can occur in certain conditions like temperature inversions.
• Negative lapse rate (temperature decreases with altitude): This is typical in the troposphere and indicates stable atmospheric conditions.
• Zero lapse rate (temperature remains constant): This would occur in an isothermal layer, where temperature doesn't change with altitude.

Practical Applications

The environmental lapse rate is crucial for understanding:

• Atmospheric stability and weather prediction
• Flight conditions, especially for aircraft
• Mountain weather patterns and avalanche risks
• Climate studies and weather forecasting models