Definition
A standardized scale used to describe how rapidly ice is accumulating on an aircraft in flight. The four reporting categories are Trace, Light, Moderate, and Severe. Each category reflects the rate of ice buildup and the degree to which anti-icing or de-icing equipment, a heading change, or an altitude change is needed to manage the encounter.
Plain English
A four-step scale pilots use to report how fast ice is forming on the aircraft, ranging from barely noticeable to so fast that the airplane can no longer cope with it.
Context Anchor
Seen in structural icing discussions, weather briefings, and pilot reports of ice encountered in flight.
Derivation
Intensity comes from a Latin idea meaning strength or degree. In this term, it points to the degree of icing—the seriousness and rate of ice buildup—not to a different kind of ice.
Why Pilots Care
Correct identification of intensity guides immediate decisions such as altitude changes or diversion to prevent loss of performance or control.
Grounding Statement
A light icing report means ice is building slowly; a severe icing report means ice is building so fast that staying there can become dangerous very quickly.
Intuition Check
Do not read icing intensity as just “how thick the ice looks.” In aviation, it means how fast the ice is accumulating and how well the airplane can cope with it.
Example Sentence 1
The pilot reported moderate icing at 8,000 feet and requested a climb to get on top.
Example Sentence 2
Severe icing intensities forced an immediate descent to exit the cloud layer.