Small, phreatic explosions from volcanic hydrothermal systems pose a substantial proximal hazard on volcanoes, which can be popular tourist sites, creating casualty risks in case of eruption. Volcano monitoring of gas emissions provides insights into when explosions are likely to happen and unravel processes driving eruptions. Here, we report SO₂ flux and plume height data retrieved from TROPOMI satellite imagery before, during, and after the 9 December 2019 eruption of Whakaari/White Island volcano, New Zealand, which resulted in 22 fatalities and numerous injuries. We show that SO₂ was detected without explosive activity on separate days before and after the explosion, and that fluxes increased from 10 to 45 kg/s ~40 min before the explosion itself. High temporal resolution gas monitoring from space can provide key insights into magmatic degassing processes globally, aiding understanding of eruption precursors and complementing ground-based monitoring.

火山热液系统的小型潜水爆炸对火山造成了重大的近端危害，火山可能是受欢迎的旅游景点，在喷发时会造成人员伤亡。火山对气体排放的监测提供了关于何时可能发生爆炸和解开推动喷发的过程的见解。在这里，我们报告了在 2019 年 12 月 9 日新西兰华卡里/怀特岛火山爆发之前、期间和之后从 TROPOMI 卫星图像中检索到的SO ₂通量和羽流高度数据，该火山导致 22 人死亡和多人受伤。我们证明 SO ₂在爆炸前后不同的日子里检测到没有爆炸活动，并且在爆炸本身之前的 40 分钟，通量从 10 增加到 45 公斤/秒。来自太空的高时间分辨率气体监测可以提供对全球岩浆脱气过程的关键见解，有助于了解喷发前兆并补充地面监测。