The warming of the last 50 or 60 years is likely the root cause of the low-grade civil wars that have been flaring up in the belt just south of the Sahara, from northern Nigeria to South Sudan and the Horn of Africa. Australia is adapting to a new regime of droughts and bushfires followed by rains and floods. Dengue fever is returning to Florida.
Here in B.C., we've seen our forests turn into a pine-beetle utopia, and climate change may finish off the wild salmon regardless of fish farms. Our governments are doing as little as possible about it.
Like St. Augustine praying for release from his sexual urges, we dream of a future without fossil fuels -- "But not yet, O Lord!" Clearly our changing climate will eventually impose fossil-fuel celibacy on us whether we're ready or not, and that will mean extremely difficult political and economic decisions.
Two hundred years ago, climate change drove politics in ways the politicians of the day didn't even recognize. But their responses helped create our world.
The agent of climate change in 1816 wasn't carbon dioxide; it was the Indonesian volcano Tambora. When it erupted in April 1815 it threw 55-million tons of sulfur dioxide into the stratosphere. There it converted into sulfuric acid and spread in tiny droplets around the world, screening a small percentage of sunlight.
The authors of a new book about that event are a father-and-son team, William the father holding a PhD in American history and Nicholas the son a PhD in meteorology. Together they've written a thought-provoking and informative account on the ways in which Tambora did indeed change history.
The biggest eruption in history
Standing on the island of Sumbawa, a little east of Java, Tambora in early 1815 was one of the highest mountains in what is now Indonesia. After a big eruption on April 5, Sir Stamford Raffles -- then the governor of Java -- heard it from over 1,290 kilometres away. He observed ash falling the next morning, but had no idea where the volcano might be.
Five days later Tambora's magma column collapsed and the top 915 metres of the volcano blew into the atmosphere -- 160 cubic kilometres of rock, dust and ash, the biggest eruption in history. Its "volcanic explosivity index" was seven, 10 times greater than Krakatoa (1883) and Pinatubo (1991), and 100 times greater than Mount St. Helens (1980). The Klingamans say an estimated 90,000 people died in Indonesia, most of them from starvation or disease following the destruction of crops and livestock and the contamination of water.
Today, the media would be covering the eruption in minute-by-minute detail, and Commander Chris Hadfield https://twitter.com/Cmdr_Hadfield on the International Space Station would be tweeting photos of it from space. But in 1815, it took a long time for the news to spread around the world. Tambora's sulfuric acid droplets travelled faster -- around the world in two weeks, and reaching the poles in two months.
High in the stratosphere, the droplets reflected sunlight back into space, cooling the planet below. When the effects began to be felt near the end of 1815, no one in Europe or North America connected them with vague reports of a big eruption in the faraway East Indies.
Europe and North America were at a historic juncture at that point. The U.S. and Britain had just concluded the War of 1812, with Canada remaining in British hands. Napoleon, having left Elba as Tambora was erupting, had ruled France for the Hundred Days, met his Waterloo at Waterloo, and been packed off to more serious exile in the South Atlantic. The French Revolution had been turned back; kings and aristocrats ruled again.
From victory to depression
Britain, after a generation of wars, demobilized its armies and put its naval officers on half-pay. Military contracts ended, including those purchasing Irish food and British textiles to feed and clothe British soldiers. The kingdom toppled straight from victory to depression.
The postwar U.S. was also dealing with economic issues, cutting some taxes while keeping others and creating the first protective tariff. The Americans already had infant industries that would have been destroyed by a new flood of British and European imports. Congress also voted itself its first raise since the Revolution, going from $6 a day to a yearly stipend of $1,500. It would cost many congressmen their political careers.
The U.S. also had lively print media, serving a remarkably literate population. In early 1816, American papers were full of pop-science reports on strange sunspots recently observed -- and which could be seen with the naked eye because of a kind of haze in the atmosphere. Perhaps, the newspapers speculated, the sunspots explained the oddly mild winter the country had just enjoyed.
In fact, the Klingamans argue, Tambora's sulfuric-acid droplets were the reason: they re-radiated some of the heat they absorbed, at least in the middle and lower latitudes: "Because the aerosol cloud from Tambora heated the stratosphere in the middle latitudes, but not in the Arctic, it enhanced the stratospheric westerly winds around the polar vortex."
The effect was to leave eastern North America relatively warm, while carrying storms across the Atlantic to northern and central Europe. Then, when spring came to the Arctic, the aerosol cloud pumped more heat into the north and broke the wind barrier penning up Arctic air. That air moved south in the spring and summer of 1816.
Snow in Quebec City on June 6
In early June, New England and Quebec basked in "hot and sultry weather," according to a Montreal report. Then the jet stream swung far to the south, pulling Arctic air as far as North and South Carolina. That air met normal warm, moist air masses and by June 6 snow was falling in Quebec City. It kept falling. Across New England temperatures dropped by 30 degrees.
So it went, all summer: rain, snow, and bitter cold. In Europe, 10,000 English tourists found themselves trapped in Switzerland by endless chilly rain. Among them were Percy Shelley and his lover Mary Godwin, along with Lord Byron, all living near Geneva. Unable to sight-see, they spent the summer reading and writing -- with Mary writing a novel called Frankenstein.
Europe's peasants and workers had no such distraction. The postwar depression put them out of work, and the result was serious social unrest. The ruin of the crops by the miserable weather made matters much worse. Robert Peel, as the secretary for Ireland, created a new police force to keep the Irish from rebelling; they were the first Peelers or Bobbies.
Meanwhile, English workers were demanding some kind of government aid. The British government of the day saw this as an utterly bizarre idea. Helping the poor was the job of the charitable rich, or the local parish.Yet serious uprisings in Ireland and England were a real threat. Grudgingly, the government found some money for relief. It was very little, but it set a dangerous precedent for the next two centuries.
Another precedent was emigration. By the thousands, peasants across Europe headed for the seaports to try their luck in North America. Meanwhile the farmers of New England, their crops ruined, abandoned their farms and headed for the far west of Ohio and Indiana.
Americans also turned to religion, assuming that the weather meant God was displeased with them. Religious revivals energized the churches, and would continue to do so for the next two centuries. Among the New England migrants was a boy called Joseph Smith, who would grow up to found the Mormons.
Among the intelligentsia, debates raged over the cause of the weather: were the forests causing it, and would cutting them down warm the climate? What about those sunspots? News stories endlessly invoked the memories of the "oldest residents" to prove that nothing like this summer had been seen in decades, if ever. That uncertain standard led more people to start keeping regular weather records, as Thomas Jefferson had been doing for almost 50 years.
Two centuries of repercussions
Tambora's influence on world climate faded out over the next few years, but it had triggered some trends that continue two centuries later. The Klingamans pay little attention to 1816 outside Europe and North America, but they do note that cholera erupted out of northeastern Bengal in the winter of 1816-17, a season of failed crops and famine. British troops carried cholera into Nepal, and two centuries later Nepali troops would carry it to Haiti.
Other trends continue. European migration to North America, and westward migration inside North America, have transformed both continents. American religiosity persists, and some religious leaders still blame the sinful victims for disasters like Hurricane Katrina. Many Americans still resent government spending and the taxes that support it.
The entire genre called science fiction came alive when Frankenstein's monster first opened his eyes amid the endless Swiss thunderstorms of 1816. The counter-revolutionary regimes that ousted Napoleon failed to deal with the social consequences of the year without a summer. Future governments would try (and usually fail) to deal more justly with such consequences.
Modern climate science -- in a sense, all modern science -- was born in that cold summer of 1816. Without the consistent records kept since then, we would literally not know what's hit us. Instead we would be idly squabbling about sunspots, old folks' memories, and the effects of deforestation to explain (or deny) global warming.
Tambora was the disaster that made the modern world. Now we will see if the modern world can stave off the disaster it has made for itself.
Original Article
Source: thetyee.ca
Author: Crawford Kilian
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