What is the standard pressure at sea level?

The standard pressure at sea level is defined as 29.92 inches of mercury (Hg). This value is established by the International Organization for Standardization (ISO) and is based on the average atmospheric pressure at sea level under standard conditions. It is a foundational reference used in meteorology and aviation to calibrate altimeters and provide a consistent measurement of atmospheric pressure.

Understanding this standard is crucial because it allows meteorologists to compare weather conditions across different locations and altitudes. The pressure can vary based on weather systems, temperature, and altitude, but for any reliable standard reference at sea level, 29.92 inches of mercury is the benchmark.