Tambora’s Eruption Led to the “Year Without Summer”
The biggest volcanic eruption in recorded human history happened in Mount Tambora, on Sumbawa Island in the Dutch East Indies (today’s Indonesia). It was preceded by five days of rumblings, starting on April 5th, 1815, when a loud eruption occurred, with a thunderous clap that was heard almost a thousand miles away. When Tambora finally blew up in a grand finale on April 10th, 1815, it was the strongest volcanic explosion of the past ten thousand years.
After the initial pop on April 5th, Mount Tambora had smoldered for the next few days, giving off faint detonation sounds from time to time. Then, on April 10th, people in Sumatra, 1600 miles away, were shocked by what sounded like the boom of big guns opening up nearby. It was the sound of Tambora going off. The eruption instantly killed about 12,000 inhabitants of Sumbawa Island in a cataclysmic explosion. 80,000 more died in the surrounding region from famine and starvation, after falling ash and pumice ruined their crops and fields.
As investigators subsequently pieced the chain of events, Tambora’s eruptions had grown more energetic early in the morning of April 10th. Flames shot up into the sky, and lava and glowing ash began pouring down the mountainside. By 8AM, bits of pumice up to 8 inches wide were falling down. Ash spewed into the air so thickly that it was pitch dark for two days, up to 400 miles away. The volcano gushed rivers of glowing ash down its sides to scorch Sumbawa island, while its tremors sent tsunamis racing across the Java Sea.
Tambora hurled ash and 12 cubic miles of gasses far up into the skies, causing extreme weather conditions around the planet. The fine ash dispersed throughout the atmosphere created odd optical phenomena throughout the world. The results included prolonged and brilliantly colored sunsets and twilights that were red or orange near the horizon, and pink or purple above.
However, the ashes spewed by Tambora into the atmosphere had other impacts that were less lovely and pleasing. The ash caused a volcanic winter, which lowered global temperatures and turned 1816 into what came to be known as The Year Without Summer. That led to an agricultural disaster of crop failures and food shortages in the northern hemisphere. The weird weather phenomena reached thousands of miles away from Tambora, all the way to the eastern United States. There, the spring and summer of 1816 were marked by a persistent dry fog that reddened and dimmed the sunlight. That May, a frost killed off most crops in upstate New York, as well as Massachusetts, Vermont, and New Hampshire, and snow fell as late as June 6 in Albany, NY. Similar examples of unusual weather were recorded around the world.