The city of Aleppo in northwestern Syria lies on a geologic fault line separating the tectonic Arabian Plate from the African Plate, and the friction between those plates renders Aleppo and the surrounding region particularly susceptible to devastating seismic events. On October 11th, 1138, one of history’s deadliest earthquakes shook northern Syria and killed about 230,000 people in Aleppo, its environs, and the surrounding region.
Aleppo was a bustling and vibrant city during the Medieval era, but in the mid 12th century, 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, and 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 by tremors that 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.
When streams of cosmic debris known as meteoroids enter Earth’s atmosphere at high speeds, simultaneously and on parallel trajectories, the transition from the airless vacuum of space to the increasingly dense atmosphere of Earth causes them to burn and disintegrate, producing meteor showers. Streaking the night skies, especially on clear and starry nights, meteor showers are among the most breathtakingly beautiful celestial sights. Usually.
In 1490, in Ming Dynasty China, meteor showers stopped being breathtakingly beautiful to the good people of Ch’ing Yang in Shaanxi (today’s Gansu Province), who witnessed one such shower suddenly go from the delightfully picturesque to the horrific, when one of the falling objects burst in the air during atmospheric reentry, killing thousands. As described by Chinese records of the era, during an intense meteor shower:
“Stones fell like rain in the Ch’ing-yang district. The larger ones were [about 3.5 pounds], and the smaller ones were [about 2 pounds]. Numerous stones rained in Ch’ing-yang. Their sizes were all different. The larger ones were like goose’s eggs and the smaller ones were like water-chestnuts. More than 10,000 people were struck dead. All of the people in the city fled to other places.”
There are similarities between Chinese source descriptions of the 1490 event and what is known of the 1908 Tunguska event, when an airburst of a meteoroid at an altitude of 5 miles above a sparsely populated part of Siberia flattened 770 square miles of forest. As such, it is likely that that the deadly 1490 Ch’ing Yang meteor shower was caused by the disintegration of an asteroid in an airburst during atmospheric entry.
China’s Loess region, the cradle of its civilization, is highly susceptible to earthquake damage because loess soil – rich windblown silt that settled over the millennia to depths of up to 300 feet – readily disintegrates when subjected to seismic activity. Between that vulnerability and China’s high population density throughout history, many of the world’s most devastating earthquakes have occurred in China.
On the morning of January 23, 1556, Ming Dynasty China was rocked by the deadliest earthquake in human history, registering around 7.9 on the Richter scale and epicentered in the Wei river basin in the Jiajing region, or modern Shaanxi.
Fissures up to 70 feet deep were opened in the earth, as the ground suddenly rose up in some place to form new hills, while in other places hills crumbled and subsided into valleys. 97 counties in Shaanxi and surrounding provinces were devastated, as the earthquake destroyed nearly everything within an area more than 500 miles wide, and damage was inflicted as far as 310 miles from the epicenter.
Recurring aftershocks continued for six months, and in many counties within the zone of destruction, over 60% of the population was killed outright, with many of the remainder injured, and all the survivors left without shelter. The loss of life was particularly high because most of the population in Shaanxi and surrounding regions, taking advantage of the region’s soft loess soil, built their homes out of earth shelters known as yaodongs – a form of artificial cave carved out of hillsides.
Such houses have the advantage of being cool in the summer and warm in the winter, but they had the disadvantage of being particularly vulnerable to seismic activity. When the 1556 earthquake struck, they collapsed, with not only the weight of a roof falling upon the inhabitants, but an entire hillside falling on and burying whole communities. When it was over, around 830,000 had been killed, and millions more were injured and/or rendered homeless.
On the morning of November 1, 1755, just as it began celebrating the religious festival of All Saints’ Day, the Portuguese capital of Lisbon – at the time one of Europe’s wealthiest cities and busiest seaports – was almost completely demolished by a powerful earthquake of a magnitude 9.0, whose shocks were felt as far away as Finland, North Africa, and even the Caribbean.
Striking around 9:40 AM, the upheaval caused fissures nearly 20 feet deep to open in the city’s streets, and because of the religious festival, a significant percentage of the population were gathered in churches and cathedrals when the tremors began, and thousands were crushed to death as the houses of worship collapsed atop them. As the tremors subsided, another danger arose as fires erupted around the city, first individually then joining together until most of Lisbon was a giant inferno.
Shaken and frightened survivors, seeking to escape the conflagration and collapsing buildings, rushed towards the harbor, where the large open squares of the royal palace promised safety from both flames and falling debris. There, they were further alarmed when they encountered the incongruous sight of a harbor without water, with ships resting on a dried seabed.
Gathering in the drying silt of the harbor’s bottom, they were led by priests in fervent prayers beseeching God’s mercy and forgiveness of whatever sins had occasioned such divine wrath. Many were still praying and begging God’s mercy in the harbor when the sea returned with a vengeance in the form of a tsunami, with a wall of water 40 feet high, and drowned them.
Total casualties are estimated to have been as high as 60,000 deaths in Lisbon alone, with a total of perhaps 100,000 deaths or more in the Lisbon region, plus many more injured. The earthquake occurred as the Enlightenment was getting into full swing, and inspired significant philosophical discourse and exchanges that furthered the development of theodicy, or the question of how a just and good God could allow what happened in Lisbon to take place.
The thorniest theodicy question was why God had sent an earthquake to crush His worshippers by the thousands in cathedrals and churches as they gathered in prayer to celebrate All Saints Day and glorify His name. The question was compounded and made thornier yet by His subsequent sending of a tsunami to drown the survivors who had been praying for His mercy in Lisbon’s harbor.
The Laki eruption of 1783 was not one of history’s most powerful volcanic events – it was not a massive and violent eruption like Vesuvius or Krakatoa or Tambora, or what most people imagine when picturing a volcano going off with a bang, blowing its top, and releasing a massive amount of energy in a dramatic explosion with fires reaching to the heavens and rivers of lava rushing down the volcano’s sides.
Indeed, the Laki eruption was not even a single explosive event, but rather 8 months of rumblings, interspersed by relatively small eruptions from time to time, with lava slowly seeping out of the side every now and then, while the volcano steadily spewed sulfuric dioxide gasses. Laki was not a vigorous and energetic volcano, but a tired and lazy one, steadily farting gasses for 8 months before it finally subsided and went quiet. Nonetheless, Laki was the deadliest volcanic eruption in human history.
Its deadliness was a result of its steady release, during its 8 months of rumbling and periodic small explosions, of massive amounts of gasses, including fluorine and over 120 million tons of sundry sulfuric dioxides, which produced fog and haze as far away as Syria. The fluorine settled on Iceland’s grass, which gave grazing animals fluoride poisoning and killed most of the island’s livestock. The loss of livestock, in turn, caused a quarter of Iceland’s human population to starve to death.
But Iceland was and remains sparsely populated, so the death of a quarter of its population did not make Laki history’s deadliest eruption. Beyond Iceland, the eruption led to a decline in temperatures in the northern hemisphere – winter temperatures in the US, for example, dropped 10 degrees Fahrenheit in 1783, and remained below normal for several years afterward. Laki’s deadliest impact was not in the US or North America, however.
The deadly impact was in Europe and the northern hemisphere to the southeast of Iceland. The summer of 1783 had been a particularly hot one, and a rare high-pressure zone formed over Iceland that year, which caused winds to blow to the southeast. Thus, when Laki began spewing prodigious amounts of sulfuric dioxide into the sky, they were carried by the winds from Iceland in a southeasterly direction, where they caused crop failures in Europe, draught in North Africa and India, Japan’s worst famine, as well as a historic famine in Egypt, a sixth of whose population starved to death in 1784.
It is estimated that the Laki eruption and its aftermath caused the deaths of an estimated six million people, making it the deadliest volcanic eruption in human history, and illustrating that low energy but large volume eruptions over an extended period can have a greater impact than massive explosive eruptions.
The eruption of Mount Tambora on Sumbawa Island in the Dutch East Indies (today’s Indonesia), which climaxed on April 10th, 1815, was the most powerful volcanic explosion of the past 10,000 years. It began on April 5, when the first loud eruption occurred with a thunderous clap that was heard nearly 1000 miles away. Over the next few days, the volcano steadily steamed, while emitting faint detonation sounds.
Then, on April 10, people in Sumatra, 1600 miles away, were startled to hear what sounded like cannons going off. Tambora had finally gone off, instantly killing about 12,000 inhabitants of Sumbawa Island in a cataclysmic explosion, while about another 80,000 died in the region from famine and starvation after falling ash and pumice ruined their crops and fields.
On Sumbawa Island, the eruptions had grown more energetic early that morning. Flames rose up into the sky, and lava and glowing ash began pouring down the mountainside. By 8 AM, bits of pumice up to 8 inches wide were raining down, and ash spewed into the air so thickly that as far as 400 miles away, it was pitch dark for two days. The volcano poured rivers of incandescent ash down its sides to scorch the island, while its tremors sent tsunamis racing across the Java Sea.
Tambora spewed ash and 12 cubic miles of gasses hurtling up into the skies, causing extreme weather conditions around the planet. The fine ash dispersed throughout the atmosphere created optical phenomena worldwide, producing prolonged and brilliantly colored sunsets and twilights that were red or orange near the horizon, and pink or purple above.
The ashes in the atmosphere had another, less lovely impact, in that they brought about 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.
Among the unusual and extreme weather phenomena caused by Tambora was the impact thousands of miles away, on the far side of the planet in the eastern US. 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. Other parts of the world also recorded weird weather phenomena that year.
Until 1839, Coringa was a bustling port city on the Bay of Bengal near the mouth of the Godavari river in India’s east coast, with a population numbering in the hundreds of thousands, and a harbor that hosted thousands of ships annually, busily loading and unloading goods and produce. Today, Coringa is a tiny village near the coast, of no distinction or note, and a population of no more than a few thousand. The drastic decline was caused by a pair of devastating cyclones, one in 1789, and an even more destructive one fifty years later, in 1839.
After centuries of prosperity, Coringa’s fortunes took a hit in 1789, when a storm that came to be called The Great Coringa Cyclone developed in December of that year, fairly late in the cyclone season by Bay of Bengal standards. It produced severe storm-tide conditions, and witnesses described a succession of three giant waves striking Coringa, with the first storm tide driving ashore all the ships in Anchorage, while the second and third waves, even bigger than the first, flowed inland to inundate with saltwater the fertile fields of the Godavari river’s delta. The city of Coringa was almost completely destroyed, and around 20,000 people were killed.
Akin to those who named the 1914 – 1918 global war “The Great War“, little knowing that an even greater one would soon follow, those who named the 1789 storm the “Great Coringa Cyclone” did not suspect that an even bigger and far more devastating cyclone would strike Coringa within a lifetime. Fifty years later, by 1839, Coringa had recovered from the 1789 disaster and rebuilt, and was more prosperous, populous, and bustling than it had ever been.
Then, on November 25, 1839, again unusually late in the Bay of Bengal’s cyclone season, a monstrous cyclone struck Coringa and brought with it a 40-foot storm surge. The extensive damage of the earlier 1789 cyclone paled in comparison to this one, which wholly destroyed the city of Coringa, wrecked all ships in the harbor and carried their wreckage miles inland, and killed over 300,000 people.
This time the damage was so extensive that the few survivors made no effort to rebuild. Most upped stakes and scattered to pursue their lives elsewhere, putting distance between themselves and what was thought to be a cursed city. The few who remained, some of whom were old enough to have experienced both devastating cyclones during their lifetimes, abandoned the coast altogether and rebuilt their community miles inland.
One of the best attested major eruptions of modern times occurred on Krakatoa Island, in the Sunda Strait between Java and Sumatra in the then Dutch East Indies (today’s Indonesia). Krakatoa, which had three linked volcanic peaks, began erupting on the afternoon of August 26, 1883 and peaked the following morning. By the time it stopped, most of Krakatoa Island and its surrounding archipelago had disappeared, collapsing into a caldera. Minor seismic activity continued for months afterward, before the volcano finally fell silent.
While the intensity and suddenness of the eruption were surprising, the eruption itself was not, for there had been plenty of warnings. For years, there had been intense seismic activity on Krakatoa, with earthquakes felt as far away as Australia. Three months before the dramatic explosion, beginning in May, the volcano started to vent steam and spew columns of ash up to 20,000 feet into the air, and give off explosions that were heard in Jakarta, 100 miles away.
That went on for a week, then quieted, before resuming again in mid-June, with a thick black cloud that covered the area for a week as the volcano erupted periodically, emitting ash and throwing up pumice that landed hundreds of miles away into the Indian Ocean.
That activity, in turn, increased tidal activity, with the results that ships had to be moored with strong chains to resist the tide’s suddenly strong ebb and flow. By early August, a desolate and abandoned Krakatoa was covered by nearly two feet of ash, and all vegetation had died, leaving only tree stumps.
The final act started early in the afternoon of August 26. By 2 PM, explosions could be heard every 10 minutes or so, and Krakatoa had spewed a 20-mile high ash cloud that was visible from far off, and ships up to 12 miles away reported a heavy ash fall, accompanied by bits of pumice up to 4 inches wide. By early evening, the seismic activity had given rise to mini tsunamis, which struck the Sumatran and Javan coasts 25 miles away.
The climax began early the following morning, with two big eruptions, at 5:30 and 6:44 AM on August 27th, which gave rise to tsunamis. That was followed at 10:02 AM by the loudest sound ever heard until then in recorded history: a cataclysmic explosion of about 180 decibels, that was equivalent to 15,000 Hiroshima bombs and that put the preceding eruptions to shame. It was heard nearly 2000 miles away in Perth, Australia, 3000 miles away on the island of Rodrigues, near Mauritius in the Indian Ocean, and produced a tsunami about 100 feet high in places.
Yet that was not the worst that Krakatoa had to offer. A fourth, and even more powerful eruption, occurred at 10:41 AM, nearly twice as loud as the previous one, at 310 decibels: so loud that it ruptured eardrums 40 miles away, and was clearly heard from 3100 miles away. A tsunami with a wall of water up to 120 feet high raced out, as ash was flung 50 miles up into the sky by an explosion that produced a pressure wave that was recorded in barometers all over the world.
Recorded on global barometers not once, but seven times, as the pressure wave raced around the planet for five days, circling the globe and coming back to the volcano, and continuing on, again and again, and again, still powerful enough to register on barometers everywhere on earth as circled the planet multiple times. The catastrophic eruptions and resultant tsunamis killed at least 36,000 according to official Dutch estimates, but modern estimates put the true casualty figures at up to 120,000.