Operational Realities: Obtaining adequate drivers and inputs for radiation belt models

Abstract:

Recent developments in 3D diffusion codes for the high energy electron radiation belt have shown that the model representation of microphysical processes in terms of diffusion coefficients, capturing radial, energy and pitch-angle diffusion (including mixed diffusion terms) is quite capable of capturing the dynamics and physics of the radiation belt system, while remaining computationally tractable; making these codes an ideal candidate for operational application. However, we hold that the major obstacle to a realistic application of such codes for now- or forecasting is our insufficient knowledge of drivers and inputs to these codes - rather than any additional improved physics in the codes. These include the specification of the initial conditions, knowledge of the background plasma distribution, the global distribution of waves, the low-energy boundary condition and the outer boundary condition.

 In this talk we will discuss realistic and affordable strategies of specifying these inputs through the use of proxies, ground based measurement techniques and data assimilative methods; present examples of where this is already possible (outer boundary and global chorus wave and plasma density specification), and outline where additional effort is needed.

 Finally we present an example of using such realistic model drivers in a state-of-the-art 3D diffusion code which demonstrates a remarkable ability of such codes to reproduce the observed dynamics - by simply using the existing physics in the code but providing the "correct" drivers and boundary conditions.