Abstract Modeling of the upper atmosphere, namely the thermosphere and ionosphere, is becoming important for applications such as orbital propagation (including satellite collision avoidance), radio propagation for communications, radar and position, navigation and timing. Whilst empirical models are quick to run, numerical models which simulate the physics and chemistry of the upper atmosphere are much slower and often neglected from validation studies. The Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension (WACCM‐X) has been used to simulate the years 1950–2024 inclusive, covering nearly seven solar cycles and the entire space age. An openly available, hourly, 1.9 (latitude) × 2.5 (longitude) degree, quarter‐scale height resolution data set has been made available to allow further exploration into the model's ability to simulate both the upper atmosphere's climatology as well short time‐scale events such as geomagnetic storms. As an example, a comparison is made against the neutral densities derived from the Challenging Mini‐satellite Payload, showing WACCM‐X consistently under‐predicts neutral densities across all geomagnetic activity levels, and low‐to‐mid solar activity, but performs well under high solar activity.
Brown et al. (Fri,) studied this question.