Gyroresonant wave particle interactions with whistler mode chorus play a fundamental role in the dynamics of the Earth's radiation belts and inner magnetosphere, affecting both the acceleration and loss of radiation belt electrons. Knowledge of the variability of chorus wave power as a function of both spatial location and geomagnetic activity, required for the computation of pitch angle and energy diffusion rates, is thus a critical input for global radiation belt models. Here we present a global model of lower band (0.1fce < f < 0.5fce) and upper band (0.5fce < f < fce) chorus, where fce is the local electron gyrofrequency, using data from five satellites, extending the coverage and improving the statistics of existing models. From the plasmapause out to L* = 10 the chorus emissions are found to be largely substorm dependent with the largest intensities being seen during active conditions. Equatorial lower band chorus is strongest during active conditions with peak intensities of the order 2000 pT2 in the region 4 < L* < 9 between 2300 and 1200 MLT. Equatorial upper band chorus is both weaker and less extensive with peak intensities of the order a few hundred pT2 during active conditions between 2300 and 1100 MLT from L* = 3 to L* = 7. Moving away from the equator midlatitude chorus is strongest in the lower band during active conditions with peak intensities of the order 2000 pT2 in the region 4 < L* < 9 but is restricted to the dayside between 0700 and 1400 MLT.

[1] We present the first simulation results for electrons in the outer radiation belt near geosynchronous orbit, where radial diffusion and resonant interactions with whistlermode chorus outside the plasmasphere are taken into account. Bounce averaged pitch-angle and energy diffusion rates are introduced in the Salammbô code for L 6.5, for electron energies between 10 keV and 3 MeV and fpe/fce values between 1.5 and 10. Results show that an initial seed population with a power law (Kappa) distribution and a characteristic plasmasheet energy of $5 keV can be accelerated up to a few MeV, for 4.5 < L < 6.6 and give a steady state profile similar to the one obtained from average satellite measurements. For a Kp = 4 magnetic storm simulation MeV electron fluxes increase by more than a factor of 10 on a timescale of 1 day. We conclude that whistler-mode chorus waves can be a major electron acceleration process at geostationary orbit.

[1] Satellites can be damaged by high energy charged particles in the Earth's radiation belts and during solar energetic particle (SEP) events. Here we review the growing reliance on satellite services, new vulnerabilities to space weather, and previous events that have led to loss of service. We describe a new European system to forecast the radiation belts up to 3 h ahead, which has three unique features: first, it uses physics-based models, which include wave-particle interactions; second, it provides a forecast for the whole outer radiation belt including geostationary, medium, and slot region orbits; third, it is a truly international effort including Europe, United States, and Japan. During the 8-9 March 2012 storm and SEP event, the models were able to forecast the >800 keV electron flux to within a factor of 2 initially, and later to within a factor of 10 of the GOES data. Although ACE and GOES data became unreliable during the SEP event, the system continued forecasting without interruption using ground-based magnetometers. A forecast of the 24 h electron fluence >2 MeV is used to provide a risk index for satellite operators. We show that including wave-particle interactions for L* > 6.5 improves the agreement with GOES data substantially and that a fast inward motion of the magnetopause to L* < 8 is related to rapid loss of relativistic electrons at geostationary orbit. Thus, we suggest that better wave-particle models and better coupling between the solar wind and the models of the magnetopause and radiation belts should lead to better forecasting.

[1] Global models of the Van Allen radiation belts usually include resonant wave-particle interactions as a diffusion process, but there is a large uncertainty over the diffusion rates. Here we present a new diffusion matrix for whistler mode chorus waves that can be used in such models. Data from seven satellites are used to construct 3536 power spectra for upper and lower band chorus for 1.5 Ä L * Ä 10 MLT, magnetic latitude 0 ı Ä | m | Ä 60 ı and five levels of K p . Five density models are also constructed from the data. Gaussian functions are fitted to the spectra and capture typically 90% of the wave power. The frequency maxima of the power spectra vary with L * and are typically lower than that used previously. Lower band chorus diffusion increases with geomagnetic activity and is largest between 21:00 and 12:00 MLT. Energy diffusion extends to a few megaelectron volts at large pitch angles > 60 ı and at high energies exceeds pitch angle diffusion at the loss cone. Most electron diffusion occurs close to the geomagnetic equator (< 12 ı ). Pitch angle diffusion rates for lower band chorus increase with L * and are significant at L * = 8 even for low levels of geomagnetic activity, while upper band chorus is restricted to mainly L * < 6. The combined drift and bounce averaged diffusion rates for upper and lower band chorus extend from a few kiloelectron volts near the loss cone up to several megaelectron volts at large pitch angles indicating loss at low energies and net acceleration at high energies.

[1] We present results from our three-dimensional (3-D) simulations using the Salammbô electron radiation belt physical model. We have run steady state and dynamic storm test case simulations to study the effect of electron-chorus resonant interactions on the radiation belt electron dynamics. When electron-chorus interactions are introduced in the code outside the plasmasphere, results show that a seed population with a kappa distribution and a characteristic energy of 2 keV is accelerated up to a few MeV in the outer radiation belt. MeV electron fluxes increase by an order of magnitude during high magnetic activity conditions especially near L* $ 5 and for equatorial mirroring particles. We have also performed a parametric study of various important parameters to investigate how our results could be influenced by the uncertainty that characterizes their values. Results of this study show that if we consider higher values of the radial diffusion coefficients, different initial states, and different boundary conditions, we always observe a peak in the L* profile of the MeV electrons when electron-chorus interactions are included.