I’m not an historian—my trade is volcanoes.  But volcanoes have been an integral part of human history, from a near human extinction 75,000 years ago due to a volcanic eruption to the grounding of aircraft in Europe last year due to a volcanic eruption in Iceland. But that eruption was only modestly sized.  To appreciate the full range of risks we might face in future, we must turn to the past.

For an example of what can happen when even more volcanic sulfur is released into the atmosphere, we can look back to 1816, “the year without a summer.”  This followed the massive 6.9 eruption of Mount Tambora in Indonesia a year earlier.  Many contemporary diaries attest to the extraordinary weather of 1816, among them the memoirs of horologist Chauncey Jerome, then living in Plymouth, Connecticut.  In his History of the American Clock Business, he recalled:

“… none of the old people will ever forget [the cold summer of 1816]...  I well remember on the seventh of June… dressed throughout with thick woolen clothes and an overcoat on, my hands got so cold that I was obliged to lay down my tools and put on a pair of mittens...  It snowed about an hour that day.  On the tenth of June, my wife brought in some clothes that had been spread on the ground the night before, which were frozen stiff as in winter…  Not half enough corn ripened that year to furnish seed for the next.”

Adverse weather conditions hit many parts of Europe, too.  In the east of England: “the crops were beaten down by heavy rains, acres of turnips were washed away … a hurricane blew, wrecking many colliers… all hopes were abandoned for the favourable termination of the harvest.” (From the Norfolk Annals.)

As a result, market prices for grain on both sides of the Atlantic doubled between 1815 and 1817.  Following so soon after the massive upheavals of the Napoleonic Wars, these hikes affected millions of people.  In May 1816, riots broke out in parts of England, including my home town of Cambridge.  The rioters armed themselves with spiked sticks and went on the rampage shouting “bread or blood.”  The Riot Act was read, carrying with it the death penalty, and the disturbances were only quelled after several protestors had been executed.

In the next years, typhus epidemics—so common during war and famine—broke out in several parts of Europe.  A doctor at Belfast’s Fever Hospital estimated that 800,000 people were infected in Ireland, of whom more than 44,000 perished from “the joint ravages of Famine, Dysentry, and Fever.”  The historian John Post described this period as the “last great subsistence crisis in the Western world.”  He found that between 1816 and 1817 death rates increased by four percent in France, six percent in Prussia, and over 20 percent in Switzerland and Tuscany, where many people literally starved to death.

More forward-looking administrations acted to combat the famine.  The French government introduced price controls and succeeded, at least in the cities, in keeping bread affordable.  In Britain, the parish poor relief system supplemented the wages of those suffering in the countryside.  Both countries also raised funds to import food from Russia and the Baltic.  But elsewhere, such welfare reforms vanished inwhat Post called “a climate of mistrust and fear.”  Anti-Semitic violence erupted in August 1819 in Würzburg in the so-called hep-hep riots, triggered when an elderly professor who had supported civic rights for Jews had to run for his life as students assaulted him.  The violence spread quickly, reaching Copenhagen, Amsterdam and Kraków.  Post saw this as the final link in “a connected sequence of events that began with the meteorological effects of the volcanic dust clouds of 1815.”

While it is all too easy to compile every last scrap of historical coincidence to exaggerate a catastrophe, there’s real substance in Post’s arguments.  Global population is now six times greater than in the early nineteenth century; it has more than doubled in just the last fifty years.  Future great eruptions thus pose increasing management challenges for the global community.  As the ash crises during the recent (and rather small) Icelandic eruptions have shown, the world is more vulnerable than we might expect.  Borrowing from HNN’s banner:  the volcanic past might be the future, too!  Forensic studies of historical and ancient volcanism give us tremendous insights into the human ecology of disasters and can help us prepare for the next massive eruption.