Cataclysmic volcanic eruptions are rare but inevitable, and their potential global consequences make them a critical focus for preparedness. The 1815 eruption of Mount Tambora in Indonesia serves as a stark reminder of the devastation such events can cause. Tambora killed 90,000 people locally and led to severe global climate disruptions. The Northern Hemisphere experienced a “year without a summer” in 1816, with temperatures dropping by 1°C and harvests failing across Europe and North America. These disruptions doubled grain prices, sparked unrest in countries like France and the UK, and plunged the U.S. into its first economic depression. In India, erratic weather fueled a cholera outbreak that became a global pandemic. Tambora’s ripple effects likely caused tens of millions of deaths worldwide.
While the world has been spared a similar event for over 200 years, geological evidence indicates a 1-in-6 chance of a massive volcanic eruption occurring this century. Such an event would have catastrophic effects in today’s interconnected world. According to Lloyd’s of London, the economic cost of a large eruption could exceed $3.6 trillion in the first year, with additional trillions in subsequent years due to disrupted weather patterns, agricultural failures, and food insecurity.
The impact of volcanic eruptions on the climate is driven by sulfur dioxide (SO₂), which is ejected into the stratosphere, forming sulfate aerosols that reflect sunlight and cool the planet. However, the magnitude of cooling depends on variables like aerosol size, plume height, and atmospheric conditions. In a warming world, these factors may behave unpredictably. For instance, faster atmospheric circulation driven by climate change could alter aerosol spread, while stratified oceans might disproportionately cool surface waters, amplifying regional climate effects. These interactions between volcanic activity and anthropogenic warming are poorly understood and require urgent study.
To address these uncertainties, researchers call for a three-part strategy. First, integrating geological evidence from ice cores and tree rings with historical volcanic records can improve understanding of past eruptions. Second, exploring how volcanic cooling interacts with ongoing climate change will help predict future impacts. Finally, policymakers need actionable strategies to mitigate the effects of a large eruption, including coupling climate, agricultural, and food-shock models to forecast cascading risks.
Despite progress in climate modeling, current frameworks underestimate the frequency and impact of large volcanic eruptions. Historical records used in standard models often exclude extreme events like Tambora, leading to gaps in predictions. Developing next-generation models with more accurate representations of volcanism is essential for preparing societies and economies. Stress testing global systems, particularly food supply chains, and including large eruptions in insurance disaster scenarios are also critical steps.
The inevitability of a future Tambora-like event underscores the urgency of preparation. With today’s larger, interconnected population, the stakes are far higher than in 1815. Proactive planning informed by advanced models and historical insights is essential to mitigate the devastating consequences of a massive volcanic eruption.