Coarse mineral dust (diameter, ≥5 μm) is an important component of the Earth system that affects clouds, ocean ecosystems, and climate. Despite their significance, climate models consistently underestimate the amount of coarse dust in the atmosphere when compared to measurements. Here, we estimate the global load of coarse dust using a framework that leverages dozens of measurements of atmospheric dust size distributions. We find that the atmosphere contains 17 Tg of coarse dust, which is four times more than current climate models simulate. Our findings indicate that models deposit coarse dust out of the atmosphere too quickly. Accounting for this missing coarse dust adds a warming effect of 0.15 W·m⁻² and increases the likelihood that dust net warms the climate system. We conclude that to properly represent the impact of dust on the Earth system, climate models must include an accurate treatment of coarse dust in the atmosphere.

粗矿尘（直径≥5μm）是影响云层、海洋生态系统和气候的地球系统的重要组成部分。尽管具有重要意义，但与测量结果相比，气候模型始终低估了大气中粗尘的数量。在这里，我们使用一个框架来估计粗尘的全球负荷，该框架利用了数十种大气灰尘尺寸分布的测量结果。我们发现大气中含有 17 Tg 的粗尘，是当前气候模型模拟的四倍。我们的研究结果表明，模型过快地将粗尘从大气中沉积出来。考虑到这种缺失的粗尘，增加了 0.15 W·m ^-2的变暖效应，并增加了尘网使气候系统变暖的可能性。我们的结论是，为了正确反映灰尘对地球系统的影响，气候模型必须包括对大气中粗灰尘的准确处理。