What is the average temperature at sea level according to ISA?

The average temperature at sea level according to the International Standard Atmosphere (ISA) is defined as 15º Celsius. This temperature is a reference point used in aviation and meteorology to provide a standard baseline for various atmospheric calculations. The ISA model is essential for understanding how atmospheric conditions affect aircraft performance and meteorological phenomena.

In the ISA model, temperature decreases with altitude at a standard rate, establishing a consistent framework for pilots and meteorologists to predict how air density and temperature vary with flight levels. Knowing that the standard temperature at sea level is 15º allows pilots to calculate density altitude, performance metrics, and ensure safe operation in varying atmospheric conditions.