Volcanic eruptions can change the planet’s climate. During major eruptions, huge amount of volcanic ash are released into the upper atmosphere which form a veil-like covering preventing sun’s rays and heat from reaching earth. Additionally, volcanic gases like sulphur dioxide has a cooling effect, opposite to that of greenhouse gases like carbon dioxide.
When Mount Tambora erupted in 1815 on the island of Sumbawa in present-day Indonesia, it ejected an estimated 120 million tons of sulphur dioxide 40 kilometers into the sky. The sulfur dioxide turned into a fine aerosol of sulfuric acid, and within weeks, it enveloped much of the earth. The aerosol layer reflected the radiation from the sun back into space, producing a worldwide chilling effect. The following year was one of the coldest in recorded history.
“Two Men by the Sea” (1817) by Caspar David Friedrich effectively captures the depressing mood following the eruption of Mount Tambora and the catastrophic global weather effects.
The eruption of Mount Tambora was the most powerful volcanic eruption humans ever witnessed. The eruption began on 5 April 1815 and continued for the next four months, during which it threw up more than 150 cubic kilometers of rock and magma producing a caldera 7 kilometers across. The mountain that originally had a peak of 4,300 meters collapsed to only 2,850 meters.
The consequences of the eruption was disastrous. Pumice stone and ash rained down on the region for weeks, as far away as South Sumatra and Borneo, 1,300 km away. The entire island was covered with ash and pyroclastic flow up to a meter deep destroying houses, crops and uprooting trees. The pumice ash that fell into the sea formed rafts up to five kilometers across. These rafts then floated out into the open sea, where they were encountered by British ships 3,600 km away.
The fine ash particles remained suspended in the atmosphere for several years producing brilliantly colored sunsets and twilights that were seen as far away as London.
The caldera of Mount Tambora. Photo: NASA
The immediate aftermath of the eruption was famine as a result of destruction of crops. This was accompanied by all kinds of disease, especially diarrhea caused by the drinking of polluted water. The famine was so serious that people in Sumbawa were reduced to eating dry leaves and poisonous tubers. Many sold their children just to obtain rice. About 48,000 people were killed on Sumbawa and 44,000 on Lombok. Tens of thousands fled to Java, Bali and South Sulawesi to escape hunger.
The effect of the eruption was not limited to Indonesia. Unseasonably cold weather killed trees, rice and animals even as far north as China and Tibet. Floods destroyed many remaining crops. In Taiwan, which has a tropical climate, snow was reported in many cities.
In Europe, still recuperating from the Napoleonic Wars, low temperatures and heavy rains resulted in failed harvests across the continent, leading to serious famine in Ireland and Wales. This was followed by major typhus epidemics in parts of Europe, including Ireland, Italy, Switzerland, and Scotland, exacerbated by malnutrition caused by the Year Without a Summer.
1816 summer temperature anomaly (°C) with respect to 1971-2000 climatology. Image credit: Giorgiogp2/Wikimedia Commons
Temperatures plummeted across North America, especially in the northeastern parts of United States and Canada. Throughout spring and summer, there was a persistent dry fog that reddened and dimmed the sunlight such that sunspots were visible to the naked eye. Frost and snow fell in the upper elevations of New Hampshire, Maine, Vermont, and northern New York in the middle of summer. Cold weather ruined most agricultural crops in North America leading to rising prices. In Canada, Quebec ran out of bread and milk and Nova Scotians found themselves boiling foraged herbs for sustenance.
The damp and the dark year of 1816 stimulated macabre and dim imaginings. Lord Byron captured the mood in his poem Darkness, which he penned in a single day when “the fowls all went to roost at noon and candles had to be lit as at midnight”.
I had a dream, which was not all a dream.
The bright sun was extinguish'd, and the stars
Did wander darkling in the eternal space,
Rayless, and pathless, and the icy earth
Swung blind and blackening in the moonless air;
Morn came and went—and came, and brought no day
Challenged by Lord Byron to a contest, many of his writer friends wrote their own scary stories. Mary Shelley came up with her lurid tale of Frankenstein, and John Polidori wrote The Vampyre.
While scientists today know for sure that the global weather phenomenon, the cold and the crop failures are the direct result of the Tambora eruption, it took decades of investigation to piece together the clues. The first scientist to suggest that there might be a link between volcanic eruptions and cooling down of the earth was Benjamin Franklin in 1783. Only much later, in the years 1914-1920, was the connection between the bad weather of 1816 and the eruption of Mount Tambora the previous year was made by, among others, W.J. Humphreys of the US meteorological office.
Mount Tambora attracts little attention today, except from a handful of tourists willing to make the 3-day climb for a view from the top and a few volcanologists.
Inside the caldera of Tambora. Photo: Georesearch Volcanedo Germany/Wikimedia Commons
References:
# Robert Evans, Blast from the Past, Smithsonian
# Bernice de Jong Boers, Mount Tambora in 1815: A Volcanic Eruption in Indonesia and Its Aftermath, Indonesia
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