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<p>Recently, measurements by the Superconducting Submillimeter-Wave Limb Emission Sounder (SMILES) satellite instrument have been presented which indicate an increase in mesospheric <span class="inline-formula">HO₂</span> above sprite-producing thunderstorms. The aim of this paper is to compare these observations to model simulations of chemical sprite effects. A plasma chemistry model in combination with a vertical transport module was used to simulate the impact of a streamer discharge in the altitude range 70–80 <span class="inline-formula">km</span>, corresponding to one of the observed sprite events. Additionally, a horizontal transport and dispersion model was used to simulate advection and expansion of the sprite air masses. The model simulations predict a production of hydrogen radicals mainly due to reactions of proton hydrates formed after the electrical discharge. The net effect is a conversion of water molecules into <span class="inline-formula">H+OH</span>. This leads to increasing <span class="inline-formula">HO₂</span> concentrations a few hours after the electric breakdown. Due to the modelled long-lasting increase in <span class="inline-formula">HO₂</span> after a sprite discharge, an accumulation of <span class="inline-formula">HO₂</span> produced by several sprites appears possible. However, the number of sprites needed to explain the observed <span class="inline-formula">HO₂</span> enhancements is unrealistically large. At least for the lower measurement tangent heights, the production mechanism of <span class="inline-formula">HO₂</span> predicted by the model might contribute to the observed enhancements.</p>