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<p>Aviation-attributed climate impact depends on a combination of composition changes in trace gases due to emissions of carbon dioxide (<span class="inline-formula">CO₂</span>) and non-<span class="inline-formula">CO₂</span> species. Nitrogen oxides (<span class="inline-formula">NO_<i>x</i></span>&thinsp;<span class="inline-formula">=</span>&thinsp;<span class="inline-formula">NO</span>&thinsp;<span class="inline-formula">+</span>&thinsp;<span class="inline-formula">NO₂</span>) emissions induce an increase in ozone (<span class="inline-formula">O₃</span>) and a depletion of methane (<span class="inline-formula">CH₄</span>), leading to a climate warming and a cooling, respectively. In contrast to <span class="inline-formula">CO₂</span>, non-<span class="inline-formula">CO₂</span> contributions to the atmospheric composition are short lived and are thus characterised by a high spatial and temporal variability. In this study, we investigate the influence of weather patterns and their related transport processes on composition changes caused by aviation-attributed <span class="inline-formula">NO_<i>x</i></span> emissions. This is achieved by using the atmospheric chemistry model EMAC (ECHAM/MESSy). Representative weather situations were simulated in which unit <span class="inline-formula">NO_<i>x</i></span> emissions are initialised in specific air parcels at typical flight altitudes over the North Atlantic flight sector. By explicitly calculating contributions to the <span class="inline-formula">O₃</span> and <span class="inline-formula">CH₄</span> concentrations induced by these emissions, interactions between trace gas composition changes and weather conditions along the trajectory of each air parcel are investigated. Previous studies showed a clear correlation between the prevailing weather situation at the time when the <span class="inline-formula">NO_<i>x</i></span> emission occurs and the climate impact of the <span class="inline-formula">NO_<i>x</i></span> emission. Here, we show that the aviation <span class="inline-formula">NO_<i>x</i></span> contribution to ozone is characterised by the time and magnitude of its maximum and demonstrate that a high <span class="inline-formula">O₃</span> maximum is only possible if the maximum occurs early after the emission. Early maxima occur only if the air parcel, in which the <span class="inline-formula">NO_<i>x</i></span> emission occurred, is transported to lower altitudes, where the chemical activity is high. This downward transport is caused by subsidence in high-pressure systems. A high ozone magnitude only occurs if the air parcel is transported downward into a region in which the ozone production is efficient. This efficiency is limited by atmospheric <span class="inline-formula">NO_<i>x</i></span> and <span class="inline-formula">HO_<i>x</i></span> concentrations during summer and winter, respectively. We show that a large <span class="inline-formula">CH₄</span> depletion is only possible if a strong formation of <span class="inline-formula">O₃</span> occurs due to the <span class="inline-formula">NO_<i>x</i></span> emission and if high atmospheric <span class="inline-formula">H₂O</span> concentrations are present along the air parcel's trajectory. Only air parcels, which are transported into tropical areas due to high-pressure systems, experience high concentrations of <span class="inline-formula">H₂O</span> and thus a large <span class="inline-formula">CH₄</span> depletion. Avoiding climate-sensitive areas by rerouting aircraft flight tracks is currently computationally not feasible due to the long chemical simulations needed. The findings of this study form a basis of a better understanding of <span class="inline-formula">NO_<i>x</i></span> climate-sensitive areas and through this will allow us to propose an alternative approach to estimate aviation's climate impact on a day-to-day basis, based on computationally cheaper meteorological simulations without computationally expensive chemistry. This comprises a step towards a climate impact assessment of individual flights, here with the contribution of aviation <span class="inline-formula">NO_<i>x</i></span> emissions to climate change, ultimately enabling routings with a lower climate impact by avoiding climate-sensitive regions.</p>