NSFGEO-NERC: Conjugate Experiment to Investigate Sources of High-Latitude Magnetic Perturbations in Coupled SWMIG system

Measurements of surface magnetic field perturbations are important to remotely sense and characterize space weather phenomena that affect electrical power grids, ground-based radio communications, and satellites and their services such as satnav. Ultimately the goal is to use the scientific understanding gained from analysing such measurements to develop computer models that can forecast the space weather impacts so that power grid and satellite operators can be warned and mitigate their effects. The first space weather forecasting services are now provided 24/7 in the UK and USA by the Met Office and NOAA, respectively, but forecasting skill is limited and greater scientific understanding and better measurements are required to improve this.

Understanding the sources of magnetic perturbations in the huge space weather system is challenging due to their simultaneous dependence on how they are driven from Space, the electrical conductivity of the upper atmosphere (ionosphere) and ground, and various asymmetries between the northern and southern polar regions. It is also hampered by insufficient data to investigate processes and validate global models, particularly in the southern hemisphere. The proposed investigations will overcome these problems through the operation and use of data from existing and future autonomous instrument platforms strategically deployed in Antarctica and Greenland, combined with supporting datasets and numerical modelling. A new combined array of magnetometers (super-accurate specialist compasses) will provide unprecedented simultaneous coverage beneath the so-called northern and southern lights (aka the aurora borealis and aurora australis), where many space weather effects are concentrated. These data enable novel experiments to isolate the respective contributions of how big the source in Space is, ionospheric conductivity, and local ground conductivity in the generation of ground magnetic perturbations.

The work will result in (1) new constraints regarding the sources of magnetic perturbations and (2) new information concerning the applicability of various assumptions widely used by the geospace research community to
interpret magnetic perturbation measurements. In addition, we will exploit a unique and exciting opportunity to explore the impacts of rapid spatial variations in ionospheric conductivity during the December 2021 solar eclipse.