Mount Tambora

See here for a brief introduction to the Gateau Method.

April 1815 saw the top 160 cubic kilometres of the Lesser Sunda Islands’ Mount Tambora disappear in what was probably the most powerful explosion in 2000 years—and the greatest recorded in history. Witnesses in Sumatra—2600 kilometres away—initially reported hearing cannonfire as the shockwave travelled outward from the exploding mountain. As far as 600 km from Tambora, ash turned the sky pitch-black for two days and completely blotted out the sun.  At least 71,000 people died in the eruption and its immediate aftermath.

Stratospheric sulfur from the eruption reflected, dimmed and reddened sunlight in North America and Europe, leading to what was called The Year Without a Summer in 1816. Frosts and snow were reported in the northern hemisphere from June to September, and harvests failed worldwide; 1816 was the coldest year since 1400 (with the exception of 1601, which followed the eruption of Huaynaputina in southern Peru). Huge storms, unusually heavy rainfall and a devastating typhus epidemic struck Europe and the eastern Mediterranean from 1816-19; food riots, looting and civil unrest followed famine throughout northwestern Europe; many livestock died in America; and untold numbers died in China from starvation and flooding during a disrupted monsoon season.

Even secular prophets forecast doom—one Italian scientist, noting unusually large sunspots, predicted that the sun would flicker out completely on July 18, 1816.

Nonetheless, the weather had some less disastrous effects.  The high price of maintaining horses during 1816 may have spurred the development of the bicycle. The weather also confined Mary Shelley, John Polidori and Lord Byron to spend the summer indoors, leading to Frankenstein, The Vampyre and Darkness respectively. Joseph Smith‘s family, like thousands of others, began its westward exodus from New England, a chain of events which would lead to the formation of the Church of Jesus Christ of Latter-Day Saints.

Perhaps in our Gateau Method timeline, the sudden cold snap led to to a messianic movement known as the Sally Revival in the Sea Islands of South Carolina. The Sallies claim to have originated in cooler climes and hailed the mild summers as blessings from their gods and ancestors; to this day, the Sallies (that is, the Tsalals’ American descendants), long for their lost homeland, much as Rastafarians long for Zion. And nowadays, as the magmatic seas beneath Yellowstone finally rumble to life, the dead—some with the aid of blood and some science—wait for the supervolcano to obliterate the United States and cover the world in darkness, so they may rule over the ruined globe. All they need now is something to trigger the eruption