Volcanic eruptions linked to rising famine risk across China's history

June 6, 2026 feature Volcanic eruptions linked to rising famine risk across China's history Hannah Bird Author Gaby Clark Scientific Editor Robert Egan Associate Editor Large volcanic eruptions may have played a bigger role in triggering historical famines across China than previously understood, according to a new study that traced links between eruptions, climate disruption, and food shortages over more than four centuries. By analyzing historical records from 1440 to 1900, Richard Warren (University of Bern, Switzerland) found that major eruptions were consistently followed by shifts in temperature and rainfall that increased the likelihood of drought, flooding, and crop failure—factors that can push vulnerable societies toward famine. But the findings also suggest volcanoes were rarely acting alone. The study, appearing in Climate of the Past, argues that eruptions should be seen as part of a wider network of environmental and social pressures that shaped whether historical communities experienced crisis. Volcanoes reshaping climate Large volcanic eruptions can affect places far beyond the volcano itself. When an eruption sends sulfur-rich gases high into the atmosphere, they form aerosol particles that reflect sunlight back into space. That can cool temperatures at Earth's surface and alter rainfall patterns for months or even years. Scientists have long linked eruptions to periods of poor harvests and food shortages around the world. Historical examples include the "Year Without a Summer" in 1816, when unusually cold conditions following the eruption of Mount Tambora led to crop failures across parts of Europe and North America. China has also experienced repeated episodes of climate instability and famine throughout its documented history. Previous studies have suggested volcanic eruptions may have contributed to events ranging from agricultural crises to the collapse of ruling dynasties. But until now, researchers say there has not been a systematic long-term analysis focused specifically on whether eruptions increased famine risk across different parts of the country. To investigate, Warren turned to the REACHES climate database, a collection of historical records that reconstruct past environmental and social conditions, tracking temperature, drought, flooding, crop failure, and famine. The analysis then compared those records with the timing of major volcanic eruptions to see whether patterns repeatedly emerged. Tracing the impacts The study found statistically significant relationships linking volcanic activity to drought, flooding, and harvest failures, strengthening the idea that eruptions can set off a chain of connected impacts, though not in the same way everywhere. Northern China showed the fastest response, with famine events tending to peak in the same year as an eruption, suggesting agricultural systems there may have been particularly sensitive to sudden cooling or rainfall disruption. Further south, the pattern was slower and more complex. In central China, famine risk often rose one to three years after an eruption. That delay appeared to align with increases in drought and crop failures, suggesting climate changes triggered by eruptions could take time to translate into agricultural losses severe enough to affect food availability. Meanwhile, southern China showed famine peaking most strongly during the year after an eruption. These regional differences highlight that climate impacts do not unfold uniformly, even within a single country. Agricultural practices, local weather systems, and differences in food distribution may all influence how quickly environmental shocks become social crises. Pressures at play Despite the patterns, Warren stresses that volcanoes did not directly cause famines, as historical food crises rarely emerge from one event alone. Instead, eruptions appeared to increase the chances that existing vulnerabilities would escalate into shortages. Case studies show how climate processes such as El Niño, disease outbreaks, fluctuations in food prices, and political responses all shaped outcomes. Government relief efforts could reduce impacts in some cases, while economic instability or poor harvests could amplify them. One example revisits the mysterious 1809 eruption—an event whose source volcano still remains uncertain but is known to have injected enough material into the atmosphere to alter global climate. The analysis suggests the eruption may have interacted with other pressures already affecting Chinese society at the time. The researchers describe these relationships as feedback loops, where environmental and social conditions influence one another. A poor harvest can drive up food prices, making shortages worse. Disease can reduce labor availability and climate shifts can undermine agricultural recovery. That means volcanic eruptions may be better understood as risk multipliers rather than direct triggers. Historical clues to the future Although the study focuses on historical China, Warren argues the findings have wider relevance today. Modern societies are generally less vulnerable to local harvest failures thanks to global trade and technological advances, but food systems remain interconnected and sensitive to environmental disruption. Recent work has highlighted concerns about how a future large eruption could affect crop production, supply chains, and food security in different regions of the world. By looking at how past societies responded to sudden climate shocks, historical records can offer clues about the conditions that make communities more resilient or more vulnerable. The study suggests that while major eruptions may not directly cause famines on their own, they can increase the likelihood that environmental stress turns into something much larger. Understanding those interactions could help improve preparedness for future climate disruptions. Written for you by our author Hannah Bird, edited by Gaby Clark, and fact-checked and reviewed by Robert Egan—this article is the result of careful human work. We rely on readers like you to keep independent science journalism alive. If this reporting matters to you, please consider a donation (especially monthly). You'll get an ad-free account as a thank-you. Publication details Richard Warren, Connecting volcanic climate impacts to famine in China using the REACHES database, Climate of the Past (2026). On EGUsphere: DOI: 10.5194/egusphere-2026-1228 Journal information: Climate of the Past Key concepts climatologydroughtsvolcanic activityEl Nino-Southern OscillationEl Nino-Southern Oscillation© 2026 Science X Network