Abstract. Recent model inter-comparison studies highlighted model discrepancies in reproducing the climatic impacts of large explosive volcanic eruptions, calling into question the reliability of global aerosol model simulations for future scenarios. Here, we analyse the simulated evolution of the stratospheric aerosol plume following the well observed June 1991 Mt. Pinatubo eruption by six interactive stratospheric aerosol microphysics models in comparison to a range of observational data sets. Our primary focus is on the uncertainties regarding initial SO₂ emission following the Pinatubo eruption in 1991, as prescribed in the Historical Eruptions SO₂ Emission Assessment experiments (HErSEA), in the framework of the model intercomparison project ISA-MIP. Six global models with interactive aerosol microphysics took part in this study: ECHAM6-SALSA, EMAC, ECHAM5-HAM, SOCOL-AERv2, ULAQ-CCM and UM-UKCA. Model simulations are performed by varying SO₂ injection amount (ranging between 5 and 10 Tg-S), and the altitude of injection (between 18–25 km). We find that the common and main weakness among all the models is that they can not reproduce the persistence of the sulfate aerosols in the stratosphere. Most models show a stronger transport towards the extratropics in the northern hemisphere, at the expense of the observed tropical confinement, suggesting a much weaker subtropical barrier in all the models, that results in a shorter e-folding time compared to the observations. Moreover, the simulations in which more than 5 Tg-S of SO₂ are injected show a large surface area density a few months after the eruption compared to the values measured in the tropics and the in-situ measurements over Laramie. This results in an overestimation of the number of particles globally during the build-up phase, and an underestimation in the Southern Hemisphere, which draws attention to the importance of including processes as the ash injection and the eruption of Cerro Hudson.

中文翻译：

---

交互式平流层气溶胶模型对 1991 年皮纳图博喷发期间不同数量和高度的 SO2 注入的响应

摘要。最近的模型比对研究强调了在再现大型火山爆发的气候影响方面的模型差异，从而质疑全球气溶胶模型模拟在未来情景中的可靠性。在这里，我们通过与一系列观测数据集进行比较，通过六个交互式平流层气溶胶微物理模型分析了 1991 年 6 月皮纳图博火山喷发后平流层气溶胶羽流的模拟演变。我们的主要关注点是关于1991 年皮纳图博火山喷发后初始 SO ₂排放的不确定性，如历史喷发 SO _2中所述排放评估实验 (HERSEA)，在模型比对项目 ISA-MIP 的框架内。六个具有交互式气溶胶微物理的全球模型参与了这项研究：ECHAM6-SALSA、EMAC、ECHAM5-HAM、SOCOL-AERv2、ULAQ-CCM 和 UM-UKCA。_{通过改变 SO 2}进行模型模拟喷射量（范围在 5 到 10 Tg-S 之间）和喷射高度（在 18 到 25 公里之间）。我们发现所有模型的共同和主要弱点是它们无法再现平流层中硫酸盐气溶胶的持久性。大多数模型显示北半球向温带的传输更强，但以观测到的热带限制为代价，这表明所有模型中的亚热带屏障要弱得多，这导致与观测相比，电子折叠时间更短。此外，模拟中超过 5 Tg-S 的 SO ₂与在热带地区测量的值和拉勒米上空的现场测量值相比，在喷发几个月后注入的表面面积密度很大。这导致在堆积阶段全球粒子数量被高估，而在南半球被低估，这引起了人们对包括火山灰注入和哈德逊山喷发等过程的重要性的关注。