Space Weather Model Descriptions: Which Should Be Published?

Abstract

Since the launch of Space Weather, a number of space weather models of all types have been reported in the journal. One of the more uncertain (and at times controversial) aspects of numerical simulations of the entire Sun-to-Earth environment is for authors (and editors) to determine when such “global” models and their results are deserving of consideration for publication. Models of solar-terrestrial processes are essential for successful predictions of these processes and of their effects on technological systems. Models can take many forms, from simple empirical expressions of the relationships among two or more physical variables to more detailed physics-based codes of subsets of the solar-terrestrial environment. Numerical simulations of the entire environment—from the Sun to Earth's ionosphere and surface—now exist. Such simulations generally incorporate modules for the several subsystems of the environment, with each module containing the relevant physics (and chemistry in appropriate cases) that is required. Many codes are in various states of testing, validation, and use in the joint U.S. National Science Foundation/NASA Community Coordinated Modeling Center. Numerical simulations must be considered and evaluated in the context of actual physical measurements. Models can be essential in deriving physical understanding from obtained data. At the same time, data are essential in validating and calibrating models. Therefore, computational simulations considered for publication should ideally report their success, or lack of success, in explaining observations. In particular, reports of failures permit a modeling group and interested outside research groups to better understand limitations of a numerical code and its modules, and thereby spur new modeling insights and developments. Often it appears that modeling teams concentrate on studying some of the largest solar-terrestrial events, especially those that involve the release of coronal mass ejections and their transit to Earth. This concentration is natural in that large events are those that can most affect technological systems. While models often do not fully explain all of the data in such large-event studies, these attempts nevertheless illuminate important limitations in the codes and their modules, and therefore point the way to new directions. But which models deserve consideration for publication? The perception of some modelers that Space Weather and its applications-oriented readers favor modeling papers that address extreme events is not in actuality the case. The journal is quite interested in publishing modeling papers that address less severely disturbed solar-terrestrial conditions, but ones that still involve perturbations of the Earth's environment that can produce effects on technical systems. One condition that requires more modeling analysis under numerical simulation is the case where enhanced relativistic electrons are produced at geosynchronous orbit when Earth is hit by an interplanetary corotating interaction region. In such a case, the enhanced relativistic electrons can produce charging of dielectric materials such as shielded electronics and coaxial cables deep inside spacecraft bodies. Modeling, beginning at the Sun and continuing to geosynchronous orbit, is of prime interest for this problem. I invite modelers to consider possible papers on this and other less disturbed but important solar-terrestrial space weather topics. Louis J. Lanzerotti is editor of Space Weather, a distinguished research professor at the New Jersey Institute of Technology, and a consultant at Alcatel-Lucent Technologies’ Bell Laboratories.