Our research group studies Earth’s space environment using a combination of observational, theoretical, and numerical techniques.

Ionosphere/Polar Wind Model Simulations of the Polar Ionosphere

Ionospheric Structure and Dynamics

The plasma density in the ionosphere forms complicated structures as a result of the interplay between ion chemistry, plasma transport, solar radiation, and magnetospheric particle precipitation. The resulting structures create a complex and dynamic environment that affects the propagation of radio signals between the ground and space.

Resolute Bay Incoherent Scatter Radar measurements of polar cap patches during a geomagnetic storm.

Magnetosphere-Ionosphere-Atmosphere Coupling

Composite image from the International Space Station showing airglow layers. The colors come from sodium (yellow, 80-105 km), lower thermospheric oxygen (green, ~120 km), and upper thermospheric oxygen (red, ~250 km).
Image Credit: NASA

Earth’s ionosphere/thermosphere is the interaction region where the atmosphere meets space. This region receives energy from both the space environment above and the atmosphere below. This interaction region overlaps with the region where most satellites orbit, i.e. low-Earth orbit (LEO). The coupling to the neutral atmosphere involves atmospheric waves and changes to chemical composition. Coupling to the magnetosphere involves precipitation of energetic particles, flows of electromagnetic energy, and escaping ions outflowing from the ionosphere into the magnetosphere.

Space Weather Modeling

Earth’s space environment is a complicated system with many different parts. Modeling these different regions requires different numerical techniques and physical approximations for the different regions. Therefore, space weather modeling requires coupled networks of models that exchange information across boundaries.

Multiscale Atmosphere-Geospace Environment (MAGE) model diagram.

Radar and Radio Science

Dr. Varney in front of the Poker Flat Incoherent Scatter Radar (PFISR)

Our group uses a variety of radio techniques to measure properties of the ionospheric plasma. We have particular expertise in the incoherent scatter (IS) radar technique, a powerful diagnostic technique capable of measuring altitude profiles and volumetric images of plasma densities, temperatures, and velocities.

Affiliated Projects

The Center for Geospace Storms (CGS) is a NASA DRIVE Science Center focused on transforming the understanding and predictability of space weather. This program include the development of the multiscale atmosphere geospace environment (MAGE) coupled model framework. More information at