Abstract. The impact of geohazards on the mental health of the local populations, is well recognized but understudied. We used natural language processing (NLP) of Twitter posts to analyse the sentiments expressed in relation to a pre-eruptive seismic unrest, and a subsequent volcanic eruption in Iceland 2021. We show that despite the small size and negligible material damage, these geohazards were associated with a measurable change in expressed emotions in the local populations. The seismic unrest was associated with predominantly negative sentiments, but the eruption with predominantly positive. We demonstrate a cost-effective tool for gauging public discourse that could be used in risk management.