The Year Without a Summer: Mount Tambora Volcanic Eruption
The dust from the 1815 eruption of Mount Tambora in the Dutch East Indies (now Indonesia) caused a worldwide lowering of temperatures during the summer of 1816, when the Almanac, legend has it, inadvertently but correctly predicted snow for July.
Largest eruption in recorded history led to global temperature drop
January 16, 2022
Have you ever heard of the Year Without a Summer? The largest eruption in recorded history—of Mount Tambora, in what is now Indonesia—caused so much ash in the atmosphere that global temperatures dropped in the summer of 1816, causing usual cold and food shortages. According to legend, The Old Farmer’s Almanac founder actually predicted snow that summer.
Even now, this year is sometimes called “Eighteen Hundred and Nearly Frozen to Death.”
What Caused 1816’s Freezing Summer?
Initially, no one had an answer back in 1816. Many conjectured that the curious weather was due to the positions of the planets, the distance between Earth and the Moon, or sunspots.
At the time, Earth was already experiencing the concluding decades of the Little Ice Age, due to a period of relatively low solar activity from 1790 to 1830 known as the Dalton Minimum. May 1816, in particular, had had the lowest sunspot number (0.1) to date since record-keeping on solar activity had begun. As you may know, we at The Old Farmer’s Almanac use solar activity as the driver of our long range weather forecasts, and one factor we’ve found is that periods of low activity are associated with colder temperatures, averaged across Earth.
But it was not only solar activity that contributed to the summerless year.
The Volcanic Eruption of Mt. Tambora
A 13,000-foot-high volcano on the island of Sumbawa, near Bali, Indonesia, was the primary cause of the Year Without a Summer. The eruption happened in April of 1815 and was one of the greatest volcanic eruptions in history. Its toll: perhaps as many as 90,000 lives.
Photo Credit: University of Arizona. Mount Tambora in Indonesia erupted in 1815, which had catastrophic effects globally.
Mt. Tambora ejected immense amounts of volcanic ash into the upper atmosphere, where it was carried around the world by the jet stream. The volcanic dust covered Earth like a great cosmic umbrella, dimming the Sun’s effectiveness during the whole cold year. This resulted in a further reduction in solar irradiance, which brought record cold to much of the world during the following summer. Such an eruption would explain the appearance of the 1816 Sun as “in a cloud of smoke.”
To which must be added the speculation surrounding a complete eclipse of the Sun on May 26, 1816, and of the Moon on June 9 and the “greater number of conjunctions of the planets than usual,” which would favor, wrote Robert B. Thomas, editor of this Almanac, “old maids and bachelors.”
The unusual cold played havoc with agricultural production in many parts of the world, directly or indirectly creating crop failures, dramatic increases in food prices, famines, cultural disruptions, and epidemics of cholera and other diseases. There were major weather events across the United States (which numbered 18 states at the time, with Vermont, Kentucky, Tennessee, Ohio, and Louisiana having been added to the original 13).
Astronaut photo of Tambora Volcano showing its summit caldera, formed when Tambora’s 13k-foot high peak was removed. Now there are layered deposits, a freshwater lake, and active stem vents still exist. Credit: NASA.
Wild Weather Events in the Summer of 1816
May frosts killed off most crops in upstate New York and the higher elevations of Massachusetts, New Hampshire, and Vermont.
On June 6, snow fell in Albany, New York, and Dennysville, Maine.
In Cape May, New Jersey, frost was reported five nights in a row in late June, causing extensive crop damage.
Lake and river ice was observed as far south as northwestern Pennsylvania in July, with frost reported as far south as Virginia on August 20 and 21.
Rapid, dramatic temperature changes occurred frequently, as temperatures sometimes went from above-normal summer levels to near freezing within hours. U.S. grain prices at least quadrupled, and oat prices increased almost eightfold.
Famine, riots, arson, and looting occurred in many European cities, while China suffered from massive crop failures and disastrous floods, and a disruption in the Indian summer monsoon season spread a cholera outbreak from the River Ganges all the way to Moscow.
Ice Storms in July?
In the United States, among the hardest hit were the people of New England. All through July, heavy frosts and occasional ice storms were commonly seen. Most people took off their winter clothing, only to have to put it on again. So many young (and old) birds were frozen that but a few were found around New England in the following 3 years.
Suicides were also not uncommon: Drought, financial panic, and lack of food goaded many to desperation.
In sum, as one anonymous poet put it:
The trees were all leafless,
the mountains were brown,
The face of the country was scathed with a frown;
And bleak were the hills,
and the foliage sere
As had never been seen at
that time of year.
A variety of almanacs and magazines have published their thoughts on the event, too:
“The Sun’s rays seemed to be destitute of heat throughout the summer; all nature was clad in a sable hue.” –Albany (N.Y.) Almanac, 1852
“During the entire season, the Sun arose each morning as though in a cloud of smoke, red and rayless, shedding little light or warmth and setting at night as behind a thick cloud of vapor, leaving hardly a trace of its having passed over the face of the Earth.” –American Magazine of History
“What would happen if the Sun should become tired of illuminating this gloomy planet?” –North American Review, 1816
Chilling Tales of the Times
At least one Vermont farmer, according to the recollection of his nephew, James Winchester, was frozen to death in the great snowstorm of June 17 of that year: “I was at my uncle’s when he left home to go to the sheep lot, and as he went out the door, he said, jokingly, to his wife: ‘If I am not back in an hour, call the neighbors and start them after me. June is a bad month to get buried in the snow, especially when it gets so near July.’ … Three days later, searchers found him … frozen stiff.”
The Rev. Thomas Robbins of East Windsor, Connecticut, kept a diary of this cold year. It tells of a man in Maine freezing to death, of a foot of June snow in the Berkshires, and ice in Massachusetts that would bear the weight of a man. The entire corn crop, except in fields nearby ponds or the ocean, failed. Hailstones beat the blossoms off all fruit trees.
Caleb Emery of Lyman, New Hampshire, visited a well in his town that was completely frozen over on the 4th of July—8 feet below the surface of the earth and it remained that way until the 25th. The 120-day drought, which began in August, created fearsome forest fire conditions and led to fires that only the November snows could quell. Sheep froze to death in their pastures. Mackerel had to be introduced as a main course instead of pork and beef.
Elisha Clark of China, Maine, according to his granddaughter, Nellie Clark Strong of Somerville, Massachusetts, often picked Baltimore orioles off the branches of orchard trees in the cold summer and brought them into the house to warm them up.
Cultural Effects of The Year Without a Summer
The lack of oats to feed the horses likely inspired the German inventor Karl Drais to research new ways of horseless transportation, which led to his invention of the ancestor of the bicycle.
Many Americans left New England for the Midwest, accelerating the westward movement of the American people. Vermont alone had as many as 15,000 people emigrate, including the family of Joseph Smith, which moved from Norwich, Vermont, to Palmyra, New York. This move may have made possible the publication of the Book of Mormon and the founding of the Church of Jesus Christ of Latter-day Saints.
In June 1816, Mary Shelley was forced by the weather to spend her Swiss holiday indoors with her literary companions, where to pass the time they decided to have a contest to see who could write the scariest story. The result was the novel Frankenstein; or, The Modern Prometheus.
Predicting Snow for the Summer of 1816
Here’s a peculiar prediction: Legend says that a July forecast of “Rain, Hail, and Snow” mistakenly appeared in The 1816 Old Farmer’s Almanac.
According to an apocryphal story that goes back to as early as 1846, Old Farmer’s Almanac founder Robert B. Thomas made this prediction for July 13, 1816. And indeed, all three—“Rain, Hail, and Snow”—did fall on this day, much to his amazement.
We’ve long looked for copies of the 1816 edition. If you find one, be sure to turn to the July and August calendar pages to see whether they contain the famous snow forecasts Thomas supposedly made for that summer.
The copy that we have simply says, “Now expect good hay weather,” “A storm is not far distant,” or “Sultry with thundershowers.”
Of course, there is no question that it did indeed snow in New England and Canada during July and August of 1816 due to the volcanic dust circling the globe.
An Elusive Edition and Almanac Lore
Certainly the story that it did is an integral part of Almanac lore.
Some accounts say the printer inserted the snow prediction as a joke while Robert B. Thomas was sick in bed with the flu.
The way we’ve always understood it, when Thomas discovered the “error,” he destroyed all—or most of—the “snow” copies and reprinted the 1816 edition with the more conventional summer forecasts. It’s said the word got out anyway, and during the winter and spring of that year, Thomas was repeatedly called upon to deny making such a ridiculous forecast for the following summer. Then, when it really did snow in July, he changed his tune and took full credit. “Told you so!” he allegedly said.
If the story is true, it is one of the earliest and best examples of a subtle skill we always referred to as “almanacsmanship.” :-)
We remain hopeful that a few copies still exist that do indeed predict “The Cold Summer of 1816,” as that summer is known in history books. If you ever find this elusive copy, please let us know!
The Year Without a Summer was far from the only time when weather determined livelihoods and changed the course of history: Did Weather Change History?