What is a Constant Altitude PPI (CAPPI)?

A Constant Altitude PPI (CAPPI) is designed to present radar data at a specified, continuous elevation above the ground. This allows meteorologists and radar operators to analyze weather phenomena and precipitation patterns from a consistent height, facilitating better interpretation of atmospheric conditions and storm development irrespective of the underlying terrain's elevation. This method is particularly valuable for tracking weather systems and storm cells, as it removes the variability introduced by changes in ground elevation.

The focus on a constant elevation, rather than varying it, is what distinguishes CAPPI from other radar display options. For instance, using different altitudes to visualize radar data might provide a more comprehensive view of atmospheric layers, but it does not deliver the same specific altitude perspective as CAPPI does. Consequently, options that mention variable altitude displays or other radar types stray from the precise definition of a CAPPI. Additionally, methods of measuring atmospheric pressure and long-range detection radar are unrelated to how CAPPI operates or its intended use in meteorological analysis.