Tambora: The Eruption That Changed the World, page 6
Once settled in the dry firmament of the stratosphere, Tambora’s global veil circulated above the weather dynamics of the atmosphere, comfortably distanced from the rain clouds that might have dispersed it. From there, its planet-girdling aerosol film continued to scatter shortwave solar radiation back into space until early 1818, while allowing much of the longwave radiant heat from the earth to escape. The resultant three-year cooling regime, unevenly distributed by the currents of the world’s major weather systems, barely affected some places on the globe (Russia, for instance, and the trans-Appalachian United States) but precipitated a truly drastic 5–6°F seasonal decline in other regions, including Europe.
The first extreme impact of a major tropical eruption is felt in raw temperature. But in western Europe, biblical-style inundation during the 1816 summer growing season wrought the greatest havoc. To understand the altered precipitation patterns fostered by volcanic weather, we must first grasp the principles of general circulation of the atmosphere. Because of the tilt of the Earth in relation to the sun and the different heat absorption rates of land and sea, solar insolation of the planet is irregular. Uneven heating in turn creates an air pressure gradient across the latitudes of the globe. Wind is the weatherly expression of these temperature and pressure differentials, transporting heat from the tropics to the poles, moderating temperature extremes, and carrying evaporated water from the oceans over the land to support plant and animal life. The major meridional circulation patterns, measuring thousands of kilometers in breadth, transport energy and moisture horizontally across the globe, creating continental-scale weather patterns. Meanwhile, at smaller scales, the redistribution of heat and moisture through the vertical column of the atmosphere produces localized “weather” phenomena, such as thunderstorms.
Figure 3.4. Weymouth Bay, 1816 (oil on canvas), John Constable (1776–1837). The Victoria & Albert Museum, London, UK. Courtesy of The Bridgeman Art Library.
In the summer after Tambora’s eruption, however, the aerosol loading of the stratosphere heated the upper layer, which bore down upon the atmosphere. The “tropopause” that marks the ceiling of the Earth’s atmosphere dropped lower, cooling air temperatures and displacing the jet streams, storm tracks, and meridional circulation patterns from their usual course. By early 1816, Tambora’s chilling envelope had created a radiation deficit across the North Atlantic, altering the dynamics of the vital Arctic Oscillation. Slower-churning warm waters north of the Azores pumped overloads of moisture into the atmosphere, saturating the skies while enhancing the temperature gradient that fuels wind dynamics. Meanwhile, air pressure at sea level plummeted across the mid-latitudes of the North Atlantic, dragging cyclonic storm tracks southward. Pioneer British climate historian Hubert Lamb has calculated that the influential Icelandic low-pressure system shifted several degrees latitude to the south during the cold summers of the 1810s compared to twentieth-century norms, settling in the unfamiliar domain of the British Isles, ensuring colder, wetter conditions for all of western Europe.7
Across Britain, a radical spike in gale-force westerlies saw platoons of rain-bearing clouds march in from the Atlantic month after month—an airy gray army that brought misery to farmers across Britain and the western continent. In a Constable painting from October 1816, Weymouth Bay—a pretty, sheltered cove on England’s south coast where the artist was on honeymoon—sits in fragile sunshine under churning gray-black skies. A couple of optimistic beachgoers—possibly Constable and his new bride—look certain to be drenched. Everywhere, the volcanic winds blew hard. The larger Arctic Oscillation, principal driver of northern European weather patterns, had shifted gears to an anomalous positive phase, as if on steroids.
Both computer models and historical data draw a dramatic picture of Tambora-driven storms hammering Britain and western Europe. A recent computer simulation conducted at the National Center for Atmospheric Research (NCAR) in Boulder showed fierce westerly winds in the North Atlantic in the aftermath of a major tropical eruption, while a parallel study based on multiproxy reconstructions of volcanic impacts on European climate since 1500 concluded that volcanic weather drives the increased “advection of maritime air from the North Atlantic,” meaning “stronger westerlies” and “anomalously wet conditions over Northern Europe.”8
Back at the ground level of observed weather phenomena, an archival study of Scottish weather has found that, in the 1816–18 period, gale-force winds battered Edinburgh at a rate and intensity unmatched in over two hundred years of record keeping.9 In January 1818, a particularly violent storm destroyed the beloved St. John’s Chapel in the heart of the city. The slowing of oceanic currents in response to the overall deficit of solar radiation post-Tambora had left anomalous volumes of heated water churning through the critical area between Iceland and the Azores (engine of the Arctic Oscillation), sapping air pressure, energizing westerly winds, and giving shape to titanic storms.
It was in this literally electric atmosphere that the Shelley party in Geneva, with the celebrity poet Byron attached, conceived the idea of a ghost story contest, to entertain themselves indoors during this cold, wild summer. On the night of June 18, 1816—a signature date in literary history—while another volcanic summer thunderstorm raged around them, Mary and Percy Shelley, Claire Clairmont, Byron, and Byron’s doctor-companion John Polidori recited the poet Coleridge’s recent volume of gothic verse to each other in the candle-lit darkness at the Villa Diodati. In his 1986 movie about the Shelley Circle that famous summer, the controversial British film director Ken Russell imagines Shelley gulping tincture of opium while Claire Clairmont performs fellatio on Byron, recumbent in a chair. Group sex in the drawing room might be implausible, even for the Shelley Circle, but drug taking is very likely, inspired by Coleridge, the poet-addict supreme. How else to explain Shelley’s running screaming from the room at Byron’s recitation of the psychosexual thriller “Christabel,” tormented by his vision of a bare-chested Mary Shelley with eyes instead of nipples?10
From such antics as these, Byron conceived the outline of a modern vampire tale, which the bitter Polidori would later appropriate and publish under Byron’s name as a satire on his employer’s cruel aristocratic hauteur and sexual voracity. For Mary, the lurid events of this stormy night gave literary body to her own distracted musings on the ghost story competition, instituted two nights earlier. She would write a horror story of her own, about a doomed monster brought unwittingly to life during a storm. As Percy Shelley later wrote, the novel itself seemed generated by “the magnificent energy and swiftness of a tempest.”11 Thus it was that the unique creative synergies of this remarkable group of college-age tourists—in the course of a few weeks’ biblical weather—gave birth to two singular icons of modern popular culture: Frankenstein’s monster and the byronic Dracula.12
Figure 3.5. The number of extreme high-wind days measured in Edinburgh spiked following Tambora’s eruption, as this graph clearly shows. The second spike corresponds to the meteorological perturbance following Krakatau’s eruption in 1883. (Alastair Dawson et al., “A 200-Year Record of Gale Frequency, Edinburgh, Scotland: Possible Link with High-Magnitude Volcanic Eruptions,” The Holocene 7.3 [1997]: 339).
A week after the memorable night of June 18, Byron and Shelley almost came to grief sailing on Lake Geneva, caught unawares as another violent storm swept in from the east. “The wind gradually increased in violence,” Shelley recalled, “until it blew tremendously; and, as it came from the remotest extremity of the lake, produced waves of a frightful height, and covered the whole surface with a chaos of foam.” By some miracle they found a sheltered port, where even the storm-hardened locals exchanged “looks of wonder.” Onshore, trees had blown down or been shattered by lightning.13
The pyrotechnical lightning displays of June 1816 ignited the literary imaginations of Mary Shelley and Lord Byron. In perhaps the most famous stanza of Childe Harold’s Pilgrimage—“Could I embody and unbosom now / that which is most within me”—Byron defines emotional “expression” itself by the single word, “Lightning.” Likewise in Frankenstein, Mary Shelley uses the experience of a violent thunderstorm as the scene of fateful inspiration for her young, doomed scientist:
When I was about fifteen years old … we witnessed a most violent and terrible thunder-storm. It advanced from behind the mountains of Jura; and the thunder burst at once with frightful loudness from various quarters of the heavens. I remained, while the storm lasted, watching its progress with curiosity and delight. As I stood at the door, on a sudden I beheld a stream of fire issue from an old and beautiful oak, which stood about twenty yards from our house; and so soon as the dazzling light vanished, the oak had disappeared, and nothing remained but a blasted stump.14
Frankenstein’s life is changed in this moment; thenceforth he devotes himself, with maniacal energy, to the study of electricity and galvanism. In the fierce smithy of that Tamboran storm, Frankenstein is born as the anti-superhero of modernity—the “Modern Prometheus”—stealer of the gods’ fire.
THE FIRST METEOROLOGIST
Jeff Masters, a professor of meteorology at the University of Michigan, is perhaps the most-read weather blogger in the United States. In an extensive posting in June 2011, he reflected on the wave of apocalyptic storms, floods, and droughts of the previous twelve months across the United States and the globe as probably the most tumultuous planetary sequence of extreme weather events since 1816.15 That Masters, a preeminent meteorologist and historian of our own era of climate deterioration, would consider 1816 the baseline example for global “extreme weather” in the twenty-first century impresses on us the historical scale of the storms that inspired Mary Shelley and her talented circle that legendary summer on the shores of Lake Geneva. Indeed, in the dozen millennia since the retreat of the glaciers opened the door to human civilization, people have rarely, if ever, seen weather like it.
The folkloric history of 1816’s extreme weather, especially in Europe and North America, looms large in the minds of meteorologists. That the myriad legends of the “Year without a Summer” have some statistical basis in the temperature record is owed—at least in England—to a man with a strong claim to the title of “father of meteorology”: the austere Quaker from Tottenham, Luke Howard. Howard’s landmark publication, Essay on the Modification of Clouds (1803), introduced the basic cloud classifications—cirrus, nimbus, and so forth—still in use today. The essay inspired fan mail from the German poet-scientist Goethe, while in 1813 Thomas Forster credited Howard with “the daily increasing attention devoted to this science.”16
The first wave of modern European interest in meteorology, with Luke Howard at the vanguard, coincided with the historically cold and cloudy decade of the 1810s.17 From 1807 to 1819, Howard maintained the first professional almanac of British weather conditions, complete with detailed statistical tables and prolific commentary. Its very title, The Climate of London, proclaimed the first principle of modern climatology: that “climate” is the aggregate of weather conditions in a particular region over time, to be distinguished—as a legitimate science—from the vulgar gossip, anecdote, and superstition that traditionally surround the weather (a discourse as “dreary” as the weather itself is so often complained to be).
Howard’s Climate of London offers hard evidence of the altered weather patterns across western Europe produced by Tambora’s eruption. By the first week of January 1816, Howard was recording “gales” and “violent storms of wind and rain” in London and elsewhere on a near daily basis. Provincial correspondence brought accounts of never-before-seen storm activity. The winter also brought the first indications of the historical cold temperatures that would afflict the country through 1816 and beyond. “I had … opportunity of observing at Tottenham,” Howard wrote,
the intense cold of the 9–10th of the second month, 1816 … a gale from the North East had precipitated in snow the moisture which previously abounded…. So cold was the surface on the 9th at noon, that a bright sun, contrary to its usual effect in our climate, produced not the least moisture in the snow, the polished plates of which retaining their form, refracted the rays with all the brilliancy of dew drops.18
The daytime temperature on February 9, 1816, never exceeded 20°F, slipping that night to 5 below zero and remaining there for twelve hours. It was a phenomenon of cold “not uncommon” in higher latitudes, Howard commented, but truly remarkable for the south of England. The sun shone but had seemingly lost its power of warmth.
The subsequent summer of 1816—that would live in infamy—brought a continuation of storms, gales, and cold conditions. Amazed locals reported snows on the summit of Helvellyn in northern England in July and snowdrifts five feet deep in the north of Scotland. Picking up the newspaper, Howard read naval reports in July of conditions at sea seeming more like the worst of a wild winter, including “strong gales, ships on shore, and [the] loss of anchors.” For Britons, the summer of 1816 was shaping up as a full-blown weather emergency: “From all parts of the country we hear of damage done by the late storms, and floods occasioned by the heavy rains.”19
Like many Englishmen of means during the summer of 1816, Luke Howard took advantage of the long-awaited end of the Napoleonic Wars to travel through Europe, off-limits to tourists for two decades. It was a busman’s holiday for Howard, whose meteorologist’s eye was awestruck by the continental scale of the 1816 climate crisis:
From Amsterdam to Geneva, I had ample occasion to witness the fact that the excessive rains of this summer were not confined to our own islands, but took place over a great part of the continent of Europe. From the sources of the Rhine among the Alps, to its embouchure in the German ocean, and through a space twice or thrice as broad from east to west, the whole season presented a series of storms and inundations.
Everywhere he went, Howard saw villages under water and entire neighborhoods of large cities flooded. He came upon dikes destroyed and bridges reduced to ruins by flash floods. He rode by vast fields of submerged crops and others simply borne away by torrents of water that flowed relentlessly in all directions, transforming the pleasant tourist geography of agrarian Europe in summertime into a continent-wide disaster zone.
Given the biblical flooding before his eyes, Howard was amazed to learn that to the north, in Scandinavia, farm fields lay “parched with drought” and that churches in Danzig and Riga were holding nightlong prayer vigils for rain. By shifting the latitudinal patterns of precipitation and intensifying weather systems across the board, Tambora brought both flood and drought to the Europe of 1816–18, a pattern we will see repeated around the globe.
Passing through Switzerland, Howard traveled the same scenic routes taken by Mary Shelley and her circle of friends. While Byron and the Shelleys exchanged ghost stories, Howard’s professional eye was drawn to the startling summer accumulation of snow on even the lower elevations of the alpine mountains:
I saw the snows of the preceding winter lying in very large masses, in hollows on the chain of the Jura, and on the Mole near Geneva, from whence they usually vanish in summer; and this at a time when the new snows had already begun to fall on the same summits.
Back in England in the autumn of 1816, Howard recorded more apocalyptic weather. Around lunchtime on October 7, he experienced a “loud explosion of electricity”—a bolt of lightning—that shook the ground at Tottenham for several seconds. “Thunder in long peals and vivid lightning” then continued for more than an hour. On November 6, a dense cloud of Tambora’s volcanic dust enveloped Chester in the west of England. At noon, amid impenetrable darkness, citizens of the cathedral town lit candles and carried lanterns through the streets. Hail, frost, and snow two feet deep followed in the succeeding days. The same conditions prevailed over London later in the month, where Howard recorded a noontime temperature of 2°F and the daytime darkness required coachmen to dismount to light the way for their horses.
The creeping terror inspired by Tambora’s unnatural weather regime was due to its unrelenting delivery of extreme conditions. Entering the second winter after Tambora’s explosion, Howard continued to gather reports of storm systems of “a severity almost beyond example.” In December, he listed hailstorms, gales of “an excessive degree of violence,” and earth tremors caused by lightning—just in Tottenham. Like the painter Turner, he also noted what was, unbeknown to him, the startling effect of Tambora’s aerosol cloud on the atmospheric spectrum. On December 27th, in the midst of storm clouds, the setting sun appeared before him like an angry giant, “fiery red, and much enlarged.”
With the cold, wild year of 1816 at last at an end, Howard was able to assess its severity on a hard statistical basis. The results must have shocked even this mild-mannered Quaker and put him in mind of the vengeance of the Lord. In his previous nine years of temperature observations, 1807–15—an already below-average sample owing to the impact of the 1809 Unknown eruption—the average daily temperature in London had been 50°F. In 1816, the average fell by 12 degrees, to 38°F.20 The “Year without a Summer” appears too mild a description for the meteorological annus horribilis that was 1816. More like the “Year without a Sun.”
In the pre-Tambora sections of his Climate of London, Howard’s interests are distinctly parochial, limited to weather observations in the British Isles and greater London in particular. Following his firsthand experience of volcanic weather conditions in continental Europe, however, Howard takes care to keep track of reports from abroad. His 1817 almanac lists “hurricanes” in Hamburg and Amsterdam, hailstorms across France, “excessive cold” in Lisbon, and continued “inundations” in Switzerland. In the widened horizons of an amateur weather enthusiast in 1816–17, then, we see the origins of modern synoptic meteorology, which understands weather as a cross-continental phenomenon and not simply the variation of local conditions.
