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<p>Anthropogenic emissions of aerosols and precursor compounds are known to significantly affect the energy balance of the Earth–atmosphere system, alter the formation of clouds and precipitation, and have a substantial impact on human health and the environment. Global models are an essential tool for examining the impacts of these emissions. In this study, we examine the sensitivity of model results to the assumed height of SO<span class="inline-formula">₂</span> injection, seasonality of SO<span class="inline-formula">₂</span> and black carbon (BC) particulate emissions, and the assumed fraction of SO<span class="inline-formula">₂</span> emissions that is injected into the atmosphere as particulate phase sulfate (SO<span class="inline-formula">₄</span>) in 11 climate and chemistry models, including both chemical transport models and the atmospheric component of Earth system models. We find large variation in atmospheric lifetime across models for SO<span class="inline-formula">₂</span>, SO<span class="inline-formula">₄</span>, and BC, with a particularly large relative variation for SO<span class="inline-formula">₂</span>, which indicates that fundamental aspects of atmospheric sulfur chemistry remain uncertain. Of the perturbations examined in this study, the assumed height of SO<span class="inline-formula">₂</span> injection had the largest overall impacts, particularly on global mean net radiative flux (maximum difference of <span class="inline-formula">−</span>0.35 W m<span class="inline-formula">⁻²</span>), SO<span class="inline-formula">₂</span> lifetime over Northern Hemisphere land (maximum difference of 0.8 d), surface SO<span class="inline-formula">₂</span> concentration (up to 59 % decrease), and surface sulfate concentration (up to 23 % increase). Emitting SO<span class="inline-formula">₂</span> at height consistently increased SO<span class="inline-formula">₂</span> and SO<span class="inline-formula">₄</span> column burdens and shortwave cooling, with varying magnitudes, but had inconsistent effects across models on the sign of the change in implied cloud forcing. The assumed SO<span class="inline-formula">₄</span> emission fraction also had a significant impact on net radiative flux and surface sulfate concentration. Because these properties are not standardized across<span id="page14780"/> models this is a source of inter-model diversity typically neglected in model intercomparisons. These results imply a need to ensure that anthropogenic emission injection height and SO<span class="inline-formula">₄</span> emission fraction are accurately and consistently represented in global models.</p>