Global monitoring of volcanic SO degassing with unprecedented resolution from TROPOMI onboard Sentinel-5 Precursor.

Over the last four decades, space-based nadir observations of sulfur dioxide (SO) proved to be a key data source for assessing the environmental impacts of volcanic emissions, for monitoring volcanic activity and early signs of eruptions, and ultimately mitigating related hazards on local populations and aviation. Despite its importance, a detailed picture of global SO daily degassing is difficult to produce, notably for lower-tropospheric plumes, due largely to the limited spatial resolution and coverage or lack of sensitivity and selectivity to SO of current (and previous) nadir sensors. We report here the first volcanic SO measurements from the hyperspectral TROPOspheric Monitoring Instrument (TROPOMI) launched in October 2017 onboard the ESA's Sentinel-5 Precursor platform.