The nineteenth century’s most famous volcanic eruption was that of Krakatoa, in what is now Indonesia. However, Krakatoa was eclipsed by a bigger volcanic eruption, also in Indonesia: the 1815 Mount Tambora Eruption. The biggest volcanic eruption in recorded human history, occurred on Sumbawa Island in what was then the Dutch East Indies.
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.
12. An Explosion That Shocked People 1600 Miles Away
After its initial pop on April 5th, 1815, Mount Tambora 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 on Sumbawa Island. 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 8 AM, bits of pumice up to eight 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 twelve cubic miles of gasses 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 had other impacts that were not so pretty.
The ash caused a volcanic winter, which lowered global temperatures and turned 1816 into what came to be known as The Year Without Summer. The result was disastrous crop failures and food shortages in the northern hemisphere. The weird weather phenomena reached thousands of miles away, 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 6th in Albany, NY. Similar examples of unusual weather were recorded around the world.
10. The Earthquake That Temporarily Interrupted the Crusades
The city of Aleppo in northwestern Syria lies on a geologic fault line that separates the tectonic Arabian Plate from the African Plate. The friction between those plates renders Aleppo and the surrounding region particularly susceptible to devastating seismic events. On October 11th, 1138, in the midst of the Crusades, one of history’s worst earthquakes shook northern Syria. It killed about 230,000 people in Aleppo, its environs, and the surrounding region.
Aleppo was a bustling and vibrant medieval city. In the mid-twelfth century, however, the region was ravaged by war as the recently formed Crusader states, such as the nearby Principality of Antioch, vied with the neighboring Muslim states. Aleppo, then part of the Zengid Sultanate, was at the forefront of the anti-Crusader resistance, protected by strong walls and a powerful citadel.
On October 10th, 1138, a small quake shook Aleppo. Warned by the foreshocks, most of Aleppo’s population fled the city for the countryside. Many died there when the main earthquake struck the following day, but far more would have perished had they remained in the city. There, the powerful citadel suffered extensive damage from the tremors that caused its walls to fall down, while in the city below, most of Aleppo’s houses collapsed.
The devastation extended beyond Aleppo and was widespread throughout northwestern Syria. The town of Harem, conquered by Crusaders who fortified it with a strong citadel, was particularly hard hit. The tremors shook apart and demolished its castle, and caused the local church to fall upon itself. The nearby Muslim fort of Atharib also had its citadel destroyed by the earthquake, which caused it to collapse upon and kill 600 of its garrison. The border town of Zaradna, sacked and pillaged multiple times as it changed hands between the combatants, was wholly obliterated.
However, considering what happened not long after the sacrifices stopped, maybe the natives had been on to something. On February 19th, 1600, Huaynaputina exploded in the biggest volcanic eruption ever experienced in South America during recorded history. The consequences were catastrophic locally, and produced negative impacts worldwide, including the killing of millions of Russians thousands of miles away. Naturally, the natives concluded that the end of the sacrifices had angered Supay, their god of death, who expressed his displeasure with the massive eruption.
Rumbling and booming noises were heard in the days before Huaynuptina exploded. Witnesses reported seeing fog and gasses spewing from the volcano’s crater. A local priest reported frightened natives, recently converted to Christianity, falling back on their old religious beliefs and traditions.
Shamans, not seen for years, scrambled to appease the volcano, preparing plants, flowers, pets, and virgin girls for sacrifice. During the sacrifice ceremony, the volcano spewed hot ash. The natives took it as a sign that the gods were too angry by then to be appeased by belated sacrifices, after having being ignored for so long.
Huaynaputina’s seismic and volcanic activity continued and steadily increased. By February 15th, 1600, earthquakes started. By the 18th, tremors were being felt every four or five minutes, some of them powerful enough to shake those who’d managed to sleep into wakefulness.
Finally, around 5 PM on February 19th, Huaynaputina erupted, sending a column of steam and ash high into the skies. Witnesses described the sound as that of giant cannons going off. Streams of lava began flowing down the mountainside, and when they reached the nearby Rio Tambo River, they created lahars – mudflows of volcanic slurry, debris, and water.
Volcanic ash from the Huaynaputina eruption began falling down, and within a day, the city of Arequipa, 50 miles away, was covered by ash nearly a foot deep. Falling ash was recorded over 300 miles away, in Chile and Bolivia.
Smaller eruptions continued for the next couple of weeks, until the volcano finally went quiet on March 5th. In the eruption, lava flowed about ten miles from the volcano, while lahars, or mud slides, made it all the way to the Pacific Ocean, 75 miles away.
4. Worldwide Impact: A Volcano in Peru Killed Millions in Russia
Several villages were destroyed, while the earthquakes stemming from the Huaynaputina eruption caused significant damage in Arequipa and nearby towns. About 15,000 people were killed in the immediate region.
The ashes from Huaynaputina spread into the atmosphere, and had a significant impact in the northern hemisphere, where temperatures cooled considerably. Epidemics ensued in places as far away as China and Korea. In Russia, 1601 was the coldest year in six centuries. That led to crop failures, which in turn led to the Russian Famine of 1601 – 1603. Two million people, or a third of Russia’s population at the time, perished in the famine.
The island of Kyushu, Japan, is home to Mount Unzen – a volcanic group situated on the Shimabara Peninsula, about 25 miles east of Nagasaki. Unzen has several lava domes – mounds atop volcanoes, resulting from the accumulation of slow seeping lava, which cools and solidifies before flowing very far. On May 21st, 1792, a volcanic eruption caused one of those lava domes to fall into the sea, resulting in a tsunami and earthquake that caused considerable devastation and loss of life.
It began months earlier, in late 1791, with tremors and earthquakes on the western side of Mount Unzen, which gradually made their way up to one of its volcanic peaks. In February of 1792, one of those peaks began erupting, causing lava to flow for the following two months.
As the lava kept flowing from Mount Unzen, the earthquakes and tremors continued. On the night of May 21st, 1792, two big quakes hit. They were powerful enough to shake one of the lava domes loose, causing it to collapse down the eastern side of the mountain. That triggered a landslide, which swept through the city of Shimabara down below, and continued on to Ariake Bay.
When the landslide struck the water, it caused a mega tsunami, with waves nearly 70 feet high, rising up to 187 feet high in some places because of the seabed’s topography. The tsunami traveled across Ariake Bay, until it hit the city of Higo on the other side, where it caused widespread devastation. It then bounced back across the bay, and hit the city of Shimabara, where the dust had still not settled from the landslide that had swept through it and triggered the tsunami in the first place. About 15,000 people were killed in the disaster, making it Japan’s worst volcanic eruption.
Of the roughly 15,000 killed by the Mount Unzen eruption, about 5000 were estimated to have been killed in the landslide that swept through Shimabara city. Another 5000 were estimated to have been killed by the ensuing tsunami when it reached Higo, across the bay from Shimabara.
The final 5000 were estimated to have been killed when the tsunami bounced back from Higo, recrossed the bay, and struck Shimabara. It did not go unnoticed that the eruption had occurred Mount Unzen, in the Shimabara Peninsula, but many deaths from the ensuing tsunami occurred in Higo, about 15 miles away across the Ariake Bay. That gave rise to a Japanese saying about things that happen in one place, yet impact those elsewhere: Shimabara erupted, Higo impacted.
Where Did We Find This Stuff? Some Sources and Further Reading