Michael Wiltberger

Learn More
[1] We present initial results from the Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model during the Halloween 2003 superstorm. The objective of NAIRAS is to produce global, real‐time, data‐driven predictions of ionizing radiation for archiving and assessing the biologically harmful radiation exposure levels at commercial airline(More)
[1] It is widely accepted that the ionosphere is an important source of ions in the magnetosphere and until recently this population has largely been neglected from many global simulations. In this study, a causally regulated cusp O outflow is added to the multifluid version of the Lyon‐Fedder‐Mobarry (LFM) global simulation. The cusp outflow algorithm uses(More)
[1] A multifluid version of the Lyon‐Fedder‐Mobarry global simulation model has been used to investigate the effects of outflowing ionospheric O on the magnetosphere‐ ionosphere system. To quantify these effects, we specify the number density, upward parallel velocity, and temperature of the O outflow in a limited area of the low‐altitude simulation(More)
[1] A variety of observations have shown strong seasonal variations in a vast array of magnetosphere-ionosphere parameters, including field-aligned currents, cross polar cap potential, and precipitating electron energy flux. In this paper we examine how these variations are modeled in the Lyon-Fedder-Mobarry (LFM) global-scale magnetohydrodynamic simulation(More)
[1] In this paper we continue the community-wide rigorous modern space weather model validation efforts carried out within GEM, CEDAR and SHINE programs. In this particular effort, in coordination among the Community Coordinated Modeling Center (CCMC), NOAA Space Weather Prediction Center (SWPC), modelers, and science community, we focus on studying the(More)
Among the many challenges facing space physics today is the need for an analysis and visualization package which can examine the results from numerical and empirical models as well as observational data. In this paper we introduce the CISM-DX package as a possible answer to this problem. We have created a tool which is capable of completing highly(More)
[1] A model has been developed to calculate the perturbed magnetic field at various ground-based magnetometer sites using the output of the ionospheric currents from the Lyon-Fedder-Mobarry Global MHD code. The model uses the computed ionospheric currents and the height dependence of the electrojet current above the ground, by evaluating the penetration(More)
The sawtooth mode of convection of Earth's magnetosphere is a 2- to 4-hour planetary-scale oscillation powered by the solar wind-magnetosphere-ionosphere (SW-M-I) interaction. Using global simulations of geospace, we have shown that ionospheric O(+) outflows can generate sawtooth oscillations. As the outflowing ions fill the inner magnetosphere, their(More)
[1] The tendency of global MHD models to overestimate the transpolar potential in simulations of strong geomagnetic storms and evidence of an adverse feedback of the ionospheric conductance on the potential suggest that these models lack important physics leading to the conductance enhancement. Farley-Buneman instability in the auroral ionosphere provides(More)
[1] Enhancements in F-region electron density and temperature and bottomside Pedersen conductivity caused by soft electron precipitation are shown to enhance the Joule heating per unit mass and the mass density of the thermosphere at F-region altitudes. The results are derived from the coupled magnetosphere-ionosphere-thermosphere model (CMIT) including two(More)