Effects of high-latitude thermosphere heating at various scale sizes simulated by a nonhydrostatic global thermosphere-ionosphere model

►Variation of the high-latitude Joule heating is studied at increasing spatial resolution. ►From 5°×5° to 2.5°×0.3125° longitude-latitude resolution Joule heating increases ∼40%. ►Increasing Joule heating artificially leads to an underestimation of the coupling processes. ►In high resolution simulations, dynamical cooling counteracts enhanced Joule heating. ►Better parameterizations of small-scale processes are required at high-latitude thermosphere.