Blast Through FAI Weather Exam 2025 – Master the Forecast and Soar to Success!

A surface-based temperature inversion is a meteorological phenomenon where the temperature increases with altitude in a layer of the atmosphere, contrary to the usual decrease in temperature with altitude. This inversion occurs when cooler air is trapped near the Earth's surface by warmer air above it.

One of the most common causes of surface-based temperature inversions is terrestrial radiation, particularly on clear nights. During the night, the Earth cools rapidly as it loses heat to space through radiation. If the sky is clear, this cooling can be substantial, causing the lowest layer of the atmosphere to become cooler than the air above it. Since warm air is less dense than cool air, this creates a stable layer where the cooler air is trapped at the surface, leading to the inversion.

Other factors like atmospheric pressure, humidity variations, and wind shear can influence weather patterns, but they do not directly produce surface-based temperature inversions in the same way that terrestrial radiation does under clear conditions.