The BSI reflects radio signals, useful for applications like medium and long range wavelength comms and radar. This highly variable layer depends on external drivers such as solar forcing and lower atmospheric dynamics. Combining several atmospheric models that cover the various regions from ground thru the BSI enables better specification and forecasting.
The BSI reflects radio signals, useful for applications like medium and long range wavelength comms and radar. This highly variable layer depends on external drivers such as solar forcing and lower atmospheric dynamics. Combining several atmospheric models that cover the various regions from ground thru the BSI enables better specification and forecasting.

Objective
Demonstrate and validate a high-performance computing atmospheric simulation capability that includes sufficient atmospheric modeling of the variability of the bottom-side ionosphere (BSI) at low to mid latitudes, for accurate numerical forecast of HF radio wave propagation through Earth’s atmosphere and ionosphere.

Approach

  • Develop a coupled atmospheric model, combining existing components WACCM-X (Whole Atmosphere Community Climate Model) and SAMI3 (NRL comprehensive, physics-based model of the ionosphere)
  • Constrain the lower atmosphere with lower atmosphere meteorology information from NAVGEM
  • Include D/E region chemistry and metal ions
  • Quantitatively assess model performance with data—ground-based and satellite observations—using modern HF propagation codes
  • Address science questions: How does the ion composition in the BSI (metal, molecular, proton hydrates) affect RF propagation? What are the roles of atmospheric waves (e.g., tides and gravity waves) in the BSI, especially for the initiation of sporadic-E events?

Deliverable/Value/Accomplishment

  • Provides necessary, quantitative understanding of the drivers that dominate the neutral upper atmosphere and the corresponding ionized bottom-side ionosphere
  • Coupling of mature individual models for BSI specification capability for development of validated regional and global scale model, towards transition
  • Contribution towards ESPC (Earth System Predictive Capability): an interagency collaboration between DoD, NOAA, DOE, NASA and NSF for coordination of research to operations for an Earth system analysis and extended range prediction capability