D-Region Absorption Prediction Product Archive

The D-Region Absorption Prediction Product (D-RAP) , is a real time product produced by the Space Weather Prediction Center (SWPC). D-RAP provides a suite of graphic and text information about global High Frequency(HF) radio propagation conditions relating of the ionosphere's D-region. The D-Region of the ionosphere is critically important to the propagation of HF radio signals. The lowest available frequency for HF users is directly related to the electron density in the D-Region. Due to space weather effects, the electron density can vary dramatically over time scales as short as a few minutes. The D-RAP Model uses empirically determined relationships to compute HF absorption and the highest affected HF frequencies directly from space weather input parameters.

NGDC is the National Archive for the D-RAP model outputs.

• Archived D-RAP Data
• D-RAP Validation Report
• Data Status Page - includes anomalies list, changes in model versions, etc.
• X-ray Events
• Particle Event List

D-Region Major Event Animations