1816: The Year Without a Summer

The most destructive explosion on earth in the past 10,000 years was the eruption of an obscure volcano in Indonesia called Mount Tambora. More than 13,000 feet high, Tambora blew up in 1815 and blasted 12 cubic miles of gases, dust and rock into the atmosphere and onto the island of Sumbawa and the surrounding area. Rivers of incandescent ash poured down the mountain’s flanks and burned grasslands and forests. The ground shook, sending tsunamis racing across the Java Sea. An estimated 10,000 of the island’s inhabitants died instantly. Climate experts believe that Tambora was partly responsible for the unseasonable chill that afflicted much of the Northern Hemisphere in 1816 — known as the “year without a summer” — causing 20 inches of snow to fall in New England in June. On July 4th, water froze in cisterns and snow fell again, with Independence Day celebrants moving inside to be near the fire. Failing crops and rising prices threatened American farmers, and thousands left New England for what they hoped would be a more hospitable climate west of the Ohio River. Meanwhile, some 15,000 people left Vermont, erasing seven years of growth in the Green Mountain State. Researchers today are careful not to blame every misery of those years on the Tambora eruption, because by 1815 a cooling trend was already under way.