Ishaan Tharoor writes: As summer approaches, many in the United States will be awaiting warmer, balmier days. It’s a prospect keenly felt right now by those in the nation’s capital, which has endured two weeks of ceaseless rain.

But things could be much worse. Two hundred years ago, the U.S. Eastern Seaboard registered record-low temperatures. On June 6, 1816, six inches of snow fell across wide swaths of New England. “The heads of all the mountains on every side were crowned with snow,” one area farmer wrote. “The most gloomy and extraordinary weather ever seen.”

A Connecticut clockmaker recalled at the time having to wear an overcoat and mittens for much of the summer; another bookkeeper noted in his diary that “the vegetation does not seem to advance at all.” Frosts set in and crops failed. In Montreal, there were reports of frozen birds dropping dead on the city streets. Denizens of Vermont were forced to subsist on “nettles, wild turnips and hedgehogs.”

These early Americans probably did not know the cause of the epic cold spell: A year prior, after months of rumbling, a colossal eruption occurred at Mount Tambora, on a small island in what was then the Dutch East Indies and is now Indonesia. Millions of tons of ash and sulfurous gas went dozens of miles up into the stratosphere, creating a kind of dusty veil around the planet and plunging part of Asia in darkness. [Continue reading…]