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<p>The particle size distribution (PSD) of mineral dust has a strong effect on the impacts of dust on climate. However, our understanding of the emitted dust PSD, including its variability and the fraction of super-coarse dust (diameter <span class="inline-formula">&gt;10</span> <span class="inline-formula">µm</span>), remains limited. Here, we provide new insights into the size-resolved dust emission process based on a field campaign performed in the Moroccan Sahara in September 2019 in the context of the FRontiers in dust minerAloGical coMposition and its Effects upoN climaTe (FRAGMENT) project. The obtained dust concentration and diffusive flux PSDs show significant dependencies upon the friction velocity (<span class="inline-formula"><i>u</i>_*</span>), wind direction and type of event (regular events versus haboob events). For instance, the number fraction of sub-micrometre particles increases with <span class="inline-formula"><i>u</i>_*</span>, along with a large decrease in the mass fraction of super-coarse dust. We identify dry deposition, which is modulated by <span class="inline-formula"><i>u</i>_*</span> and fetch length, as a potential cause for this PSD variability. Using a resistance model constrained with field observations to estimate the dry deposition flux and thereby also the emitted dust flux, we show that deposition could represent up to <span class="inline-formula">∼90 <i>%</i></span> of the emission of super-coarse particles (<span class="inline-formula">&gt;10</span> <span class="inline-formula">µm</span>) and up to <span class="inline-formula">∼65 <i>%</i></span> of the emission of particles as small as <span class="inline-formula">∼5</span> <span class="inline-formula">µm</span> in diameter. Importantly, removing the deposition component significantly reduces the variability with <span class="inline-formula"><i>u</i>_*</span> in the PSD of the emitted dust flux compared with the diffusive flux, particularly for super-coarse dust. The differences between regular and haboob event concentration and diffusive flux PSDs are suspected to result from a smaller and variable dust source fetch during the haboob events, and/or an increased resistance of soil aggregates to fragmentation associated with the observed increase in relative humidity along the haboob outflow. Finally, compared to the invariant emitted dust flux PSD estimated based on brittle fragmentation theory, we obtain a substantially higher proportion of super-micrometre particles in the dust flux. Overall, our results suggest that dry deposition<span id="page7178"/> needs to be adequately considered to estimate the emitted PSD, even in studies limited to the fine and coarse size ranges (<span class="inline-formula">&lt;10</span> <span class="inline-formula">µm</span>).</p>